background image
25 M
09 10 12 AM
background image
MANUAL ON GUIDELINES FOR
REHABILITATION OF COASTAL FORESTS
DAMAGED BY NATURAL HAZARDS
IN THE ASIA-PACIFIC REGION
H.T. Chan & S. Baba
International Society for Mangrove Ecosystems (ISME),
c/o Faculty of Agriculture, University of the Ryukyus,
1 Senbaru, Nishihara, Okinawa, 903-0129 Japan
International Society for Mangrove Ecosystems
and
International Tropical Timber Organization
background image
ii
© International Society for Mangrove Ecosystems (ISME) and International Tropical Timber
Organization (ITTO), 2009
All rights reserved. No part of this publication may be reproduced or stored in any form
that can be retrieved or transmitted in any form or by any means, electronic or mechanical,
including photocopy, recording or any other means, without written permission from the
publishers.
Citation:
Chan, H.T. & Baba, S., 2009. Manual on Guidelines for Rehabilitation of Coastal Forests
damaged by Natural Hazards in the Asia-Pacific Region.
 International Society for Mangrove
Ecosystems (ISME) and International Tropical Timber Organization (ITTO), 66 pp.
Published by:
International Society for Mangrove Ecosystems (ISME) and International Tropical Timber
Organization (ITTO)
Printed by:
City Reprographic Services, No. 2, Jalan Vivekananda, Brickfields, 50470 Kuala Lumpur,
Malaysia (cityrepro@yahoo.co.uk)
ISBN: 978-4-906584-13-0
Copies are available from the International Society for Mangrove Ecosystems (ISME), c/o
Faculty of Agriculture, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa, 903-
0129 Japan (isme@mangrove.or.jp)
Cover photographs:
General view of the Andaman mangroves in India by K. Tsuruda
Young plantation of Rhizophora mucronata in Malaysia by K.H. Tan
Women planting Terminalia cattapa in the Maldives by S. Yamagami
Fringing belt of planted Rhizophora stylosa in Kiribati by T. Suzuki
background image
iii
CONTENTS
PREFACE
iv
1.
TYPES OF COASTAL FORESTS
1.1
Mangrove forests
1
1.2
Beach and dune forests
4
1.3
Forests of coral islands
6
2.
NATURAL HAZARDS AFFECTING COASTAL FORESTS
2.1
Tsunamis
9
2.2
Tropical cyclones
11
2.3
Coastal erosion
13
2.4
Sea-level rise
15
3.
PROTECTIVE ROLES OF COASTAL FORESTS
3.1
Overview
19
3.2
Mangrove forests
20
3.3
Other coastal forests
22
4.
GUIDELINES FOR REHABILITATION OF COASTAL FORESTS
4.1
Overview
23
Concepts and rationale
23
Rehabilitation efforts
24
4.2
Mangrove forests
25
Rationale for rehabilitation
25
Choice of species
26
Site selection and preparation
30
Propagation and planting
31
Monitoring and tending
32
Case studies
32
4.3
Other coastal forests
37
Rationale for rehabilitation
37
Choice of species
38
Site selection and preparation
45
Propagation and planting
46
Monitoring and tending
47
Case studies
47
REFERENCES
59
background image
iv
PREFACE
The ISME/ITTO Pre-Project on Restoration of Mangroves and other Coastal Forests
damaged by Tsunamis and other Natural Hazards in the Asia-Pacific Region
 [ITTO/
ISME PPD 134/07 Rev.1 (F)] was implemented by the International Society for
Mangrove Ecosystems (ISME) from January 2008 to March 2009.
The Proceedings of the Meeting and Workshop on Guidelines for the Rehabilitation of
Mangroves and other Coastal Forests damaged by Tsunamis and other Natural Hazards
in the Asia-Pacific Region 
was the first output of the Pre-Project. Edited by Chan, H.T.
& Ong, J.E., and published in November 2008 as ISME Mangrove Ecosystems
Proceedings No. 5
, the document was a compendium of a meeting and workshop. The
meeting, organised by ISME and ITTO in collaboration with University of the Ryukyus
was held in Okinawa, Japan from 15-16 June 2007. It coincided with the 21
st
 Pacific
Science Congress held from 12-16 June 2007. The workshop was held in Bangkok,
Thailand on 23 August 2008 in conjunction with the Seventh General Assembly of
ISME. It was organised by ISME and ITTO in collaboration with Thailand Environment
Institute (TEI) and Department of Marine and Coastal Resources (DMCR) of Thailand.
Another output of the Pre-Project was the Proposal on Rehabilitation and Sustainable
Management of Mangrove Forests subjected to Commercial Harvesting for Woodchips
in Sabah, Malaysia
. Prepared by ISME for submission to ITTO by the Government of
Japan, the main objectives of the proposal are to assess the state of the mangrove forests
in Sabah previously harvested for woodchips and to prepare a five-year Mangrove
Rehabilitation Management (MRM) Plan for rehabilitation of these degraded mangroves.
Outputs of the project will include: 1) An assessment report on the degree of degradation
and recovery of the forests; 2) Establishment of six one-hectare pilot plots for
demonstrating best practice rehabilitation techniques; and 3) A five-year MRM Plan
for the affected forest areas. The project will also provide hands-on training to the staff
of the Sabah Forestry Department involved. A graduate from Japan and another from
Sabah, both engaged under the project, will be given the opportunity to pursue their
M.Sc. using data and information from this project.
The present Manual on Guidelines for Rehabilitation of Coastal Forests damaged by
Natural Hazards in the Asia-Pacific Region
 is the final output of the Pre-Project. The
manual includes introductory chapters on coastal forests (mangrove forests, beach and
dune forests, and forests of coral islands), natural hazards (tsunamis, tropical cyclones,
coastal erosion and sea-level rise), and the protective roles of coastal forests. The main
chapter provides an overview (concepts and rationale of rehabilitation, and rehabilitation
efforts), and guidelines for rehabilitation of mangroves and other coastal forests. The
guidelines include the rationale for rehabilitation; choice of species; site selection and
preparation; propagation and planting; monitoring and tending; and case studies. The
case studies provide useful lessons of success and failure of past and on-going projects
in coastal forest rehabilitation.
background image
Types of coastal forests
1
Manual on Guidelines for Rehabilitation of Coastal Forests, H.T. Chan & S. Baba, 2009; p. 1–8
1.1  Mangrove forests
Mangroves are tidal forests of tropical and sub-tropical shores. They thrive in
sheltered coastal areas with relatively calm waters such as estuaries, accreting
shores, bays and lagoons (e.g. Spalding, 2004; Duke, 2006; Cochard, 2008). They
are also found in areas protected by sand bars, islands, coral reefs and/or sea grass
beds. Under sheltered conditions, they contribute to land accretion by colonising
and stabilising mud banks with their extensive rooting systems. Trees of Sonneratia
and Avicennia are the main pioneer species. On firmer and more compact sediments
along the banks of creeks, bays and lagoons, trees of Rhizophora with stilt roots
(Fig. 1) and Bruguiera  with knee roots are the dominant species. Fringing large
rivers, mangroves may occur upstream for tens of kilometres, depending on tidal
range, freshwater discharge and topography (Giesen et al., 2007). Upstream
mangroves include Barringtonia asiaticaSonneratia caseolaris and Nypa fruticans.
Globally, mangroves occur in 114 countries and territories (Spalding et al., 1997;
Spalding, 2004). The total global area has been estimated at 181,000 km
2
 (Table
1). The centre for mangrove biodiversity is in Southeast Asia with up to 45 species
of flora. In the Pacific Islands, many of which are atolls, 31 species of mangroves
and five hybrids have been reported (Ellison, 2008). Common species found on these
islands are Heritiera littoralis,  Sonneratia alba,  Lumnitzera littorea,  Rhizophora
stylosa
Bruguiera gymnorhizaExcoecaria agallocha and Xylocarpus granatum.
Table 1. Estimation of global mangrove areas (Spalding et al., 1997)
Region
Area (km
2
)
Percent
South and Southeast Asia
75,173
41.5
Australasia
18,789
10.4
Americas
49,096
27.1
West Africa
27,995
15.5
East Africa and Middle East
10,024
5.5
Total
181,077
100
Chapter 1
TYPES OF COASTAL FORESTS
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
2
Mangrove vegetation typically displays zonation patterns dominated by one or two
species (e.g. Giesen et al., 2007; Twilley, 2008). Succession in mangroves is often
equated with zonation which has been attributed to a number of factors. Biological
factors include salinity tolerance, seedling dispersal patterns and inter-specific
competition. Physical factors include soil types, wave actions, salinity, freshwater
inflow and tidal influence.
Mangroves have developed specialised adaptive features to live in the tidal
environment which is characterised by saline, water-logged and anaerobic soils. All
mangroves are able to exclude salt from sea water (Spalding, 2004). Most species
have an ultra-filtration process at the root endodermis that is highly efficient in
excluding salt. Examples are species of Bruguiera,  Lumnitzera,  Rhizophora and
Sonneratia. Species of AegialitisAegiceras and Avicennia, which are less efficient
in salt exclusion, actively secrete salt from their leaves through salt glands. Another
morphological feature for which mangroves are best known is the development of
aerial roots. Prop or stilt roots are characteristic of Rhizophora, knee roots of
Bruguiera, pneumatophores of Avicennia and Sonneratia, and plank-like buttress
roots of Xylocarpus and Heritiera.
Mangrove forests have been categorised into various classes based on the frequency
of inundation by tides (Watson, 1928). The classes include those inundated by all
high, medium and normal high tides, and those inundated only by spring and
equinoctial tides (Table 2). Common tree species found in these inundation classes
are listed in Table 3.
Table 2. Inundation classes of mangroves (Watson, 1928)
Class
Flooded by
Height above
Flooding frequency
chart datum (m)
(times/month)
1
All high tides
0 < 2.4
56 – 62
2
Medium high tides
2.4 < 3.4
45 – 59
3
Normal high tides
3.4 < 4.0
20 – 45
4
Spring high tides
4.0 < 4.6
2 – 20
5
Equinoctial tides
4.6 +
< 2
background image
Types of coastal forests
3
Table 3. Common species found in the various inundation classes of mangroves
Inundation class
Common tree species
1. Deeply inundated by all high
Avicennia albaAvicennia marina and
tides (seaward shores)
Sonneratia alba
2. Inundated by all high tides
Rhizophora mucronata
(banks of tidal creeks)
3. Inundated by normal high tides
Bruguiera gymnorhiza, Bruguiera cylindrica,
(central mangroves)
Bruguiera parviflora, Bruguiera sexangula
and Rhizophora apiculata
4. Inundated only by occasional
Excoecaria agallocha, Ficus microcarpa,
spring tides (back mangroves)
Instia bijuga, Lumnitzera littorea,
Lumnitzera racemosa, Xylocarpus granatum
and Xylocarpus moluccensis
5. Inundated only by very rare
Cerbera manghas, Cerbera odollam,
equinoctial tides
Nypa fruticans, Oncosperma tigillarium
(riverine mangroves)
and Sonneratia caseolaris
Mangrove species can be categorised into true mangroves and mangrove associates
(Selvam, 2007). Plants that occur in the coastal environment and also found within
mangroves are considered as mangrove associates. True mangroves are species
which are adapted to the mangrove environment and do not extend into other coastal
plant communities. True mangroves consist of a core group of some 30-40 species
(Spalding, 2004). They are the most important, both numerically and structurally,
and are found in almost all mangrove communities.
Mangroves occur in ecological conditions that approach its limit of tolerance with
regard to soil salinity and inundation regime (Blasco et al., 1996). If the durations
of daily inundation were to be modified, mangrove species either re-adjust to the
new conditions through recovery or succumb to the unsuitable conditions through
mortality.
The socio-economic values of mangroves have been well documented (e.g. Clough,
1993; Spalding, 2004; Walters et al., 2008). Most of the people living in or adjacent
to mangrove areas derive their livelihood from forestry and fisheries. Rhizophora
trees are harvested for pole, firewood and charcoal production. Mangrove wood is
also used for construction of houses and fish traps. Fronds of Nypa fruticans are
particularly valued in Southeast Asia for use as thatch for roofing. Sap from its
inflorescence is tapped for producing sugar or alcoholic beverages.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
4
The linkage of mangroves and associated fisheries is well recognised (e.g. Robertson
& Duke, 1990; Walters et al., 2008). Fisheries include species that spend their entire
life-cycle in mangrove systems, species that are associated with mangroves during
at least one stage in their life-cycle, and species that are sporadic users of
mangroves. The fry of penaeid shrimps enter the mangrove environment, where they
feed and grow into juveniles and sub-adults before migrating back to the sea to
complete their life cycle. Fish species, which have a close association with
mangroves, include the grouper, snapper, sea-perch, mullet, catfish and milkfish.
Mangroves also support many mollusc species that constitute an important in situ
fishery. Edible species of oysters, mussels, cockles and gastropods are collected
for the local market. The cockle Anadara granosa is commercially cultured in
mangrove estuaries of Southeast Asia.
In recent years, mangrove ecosystems have become popular destinations for
ecotourism and nature education. Visitors are fascinated by the range of species of
flora and fauna that can be easily observed from boardwalks. Boat tours for
photography, and for watching of birds, primates and fire-flies are now generating
significant revenue for local communities.
Mangrove ecosystems have important ecological and environmental values (e.g.
Clough, 1993; Kaly & Jones, 1998). They play a role in the out-welling of nutrients
to adjacent near-shore areas, and can function as a cleansing system for sediments
and nutrients in estuaries.
Mangroves also play an important role in stabilising coastal sediments and in
protecting coastal areas from storm damage (Spalding, 2004; Braatz et al., 2007).
This role is frequently overlooked until major storm events hit coastlines where
mangroves have been removed. The massive and devastating cyclones that regularly
impact the coastline of the Bay of Bengal have drawn particular attention to these
issues (Blasco, 2008). Some countries e.g. Bangladesh have established mangrove
plantations to stabilise sediments and to reduce the impact of storm surges (Saenger
& Siddiqi, 1993).
1.2  Beach and dune forests
Beaches and dunes occur in tropical and temperate coastal areas worldwide. They
are among the most dynamic landscapes, shifting with the winds, incoming waves
and storm tides (e.g. Craft et al., 2008; Cochard, 2008; Moreno-Casasola, 2008).
Dunes are formed from sand delivered to the beach from the near-shore by waves.
The exposed sand, dried by the sun, is then transported inland by wind to form
dunes. Formation of dunes requires a source of sand, usually carried from the beach
by onshore winds, and vegetation to trap and stabilise the sand.
background image
Types of coastal forests
5
Coastal dunes serve as reservoirs of sand to re-nourish the beach during storms as
erosion transports the sand offshore where it is deposited on sand bars to be returned
gradually by the tides (Craft et al., 2008). They act as a buffer to winds and waves,
and they shelter communities in the hinterland (Moreno-Casasola, 2008). They are
also important habitats for plants and animals including the nesting of sea turtles.
Dunes are stressful environments characterised by shifting sand that abrades
vegetation, salt spray, and soils with extreme temperatures, low water holding
capacity and poor nutrient content, especially nitrogen (e.g. Cochard, 2008; Craft
et al., 2008; Moreno-Casasola, 2008).
Plant communities of coastal dunes (Fig. 2), also referred to as strand vegetation,
consist of three zones (e.g. BPA, 2004; Craft et al., 2008). They are: 1) the pioneer
zone with primary stabilising plants of mainly herbaceous species; 2) the shrub zone
with secondary stabilising plants consisting of shrubs, herbs and grasses; and 3)
the forest zone consisting of shrubs and trees. Common plant species found in the
various zones of coastal beaches and dunes are shown in Table 4.
Strand vegetation plays an important part in the formation and stabilisation of
coastal dunes (BPA, 2004). Pioneer plants trap and hold wind-blown sand in the
fore-dune and help create conditions which encourage the establishment and growth
of other plant communities such as scrub and heath forests. All plants have a role
in the development of vegetative cover and together they bring about dune
stabilisation. Sand trapped in the fore-dune by strand vegetation serves as a reservoir
of sand for the beach during periods of erosion. In the absence of dune vegetation,
sand from the beach moves inland, resulting in coastline recession.
Table 4. Common plant species found in the various zones of coastal beaches
and dunes
Zone
Common plant species
Pioneer
Ischaemum muticum,  Canavalia rosea,  Wedelia biflora,  Ipomoea pes-
caprae
 and Sesuvium portulacastrum
Shrub
Spinifex littoreusVitex trifoliaWedelia bifloraPandanus odoratissimus,
Pandanus tectorius,  Scaevola taccada,  Pemphis acidula,  Hibiscus
tiliaceus
 and Thespesia populnea
Forest
Calophyllum inophyllum,  Terminalia cattapa,  Barringtonia asiatica,
Melaleuca cajuputi and Casuarina equisetifolia
Establishing vegetation cover will reduce wind speed and thereby stabilises the dunes
by trapping sand (Cochard, 2008). Shading by foliage increases water retention of
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
6
the sand substrate and improves its binding capacity. Specialised flora of creeping
herbs (e.g. Ipomoea pes-caprae and Canavalia rosea) sedges and grasses (e.g.
Spinifex littoreus) plays an important role in fore-dune stabilisation. The richness
of plant species of strand vegetation can be used as an indicator of dune stability.
In Southeast Asia and the Pacific Islands, two formations of strand vegetation are
commonly associated with sandy beaches and dunes (Wibisono & Suryadiputra,
2006; UNEP, 2007; Giesen et al., 2007; Hanley et al., 2008). They are:
Pes-caprae  formation
This formation is dominated by the creeper Ipomoea pes-caprae, which is a common
cover crop of dune strands. If the substrate is stable, the plant will grow rapidly
and dominate the back part of the beach. Establishment of this creeper is usually
followed by the growth of grasses such as Spinifex littoreus, Cyperus maritime and
Ischaemum muticum, and herbs such as Canavalia roseaDesmodium umbellatum,
Vigna marinaCrotalaria striata and Calopogonium mucunoides.
Barringtonia  formation
This formation occurs behind the Pes-caprae formation. Common tree species are
Barringtonia asiatica,  Cerbera odollam,  Terminalia cattapa, Artocarpus altilis,
Morinda citrifolia,  Erythrina variegata,  Hibiscus tiliaceus,  Hernandia peltata and
Casuarina equisetifolia. Shrub species include Pluchea indica,  Desmodium
umbellatum
Sophora tomentosaPemphis acidula and Ximenia americana.
People have always appreciated the beauty and recreational values of beaches and
dunes (Moreno-Casasola, 2008). Many would crowd the beaches as they are perfect
tourist destinations for sun, sea and sand (Wong, 2003). Of all the coastal systems,
the dunes have suffered the greatest degree of human pressure. Many have been
irreversibly altered by human activities such as tourist resorts, golf courses and urban
growth. Development of the shore often leaves no room for dunes to migrate inland,
as occurs when sea-level rises (Craft et al., 2008). The combination of changing
environmental conditions and urban encroachment makes coastal dunes a globally
endangered ecosystem.
1.3  Forests of coral islands
Atolls consist of a raised rim of carbonate sand and gravel, surrounded by submerged
reefs on the ocean side, and enclosing a lagoon (e.g. Solomon & Forbes, 1999;
Woodroffe, 2008). The rim may be continuous, but it usually consists of a series of
coral islands separated by channels, which allow exchange of water between the
lagoon and the ocean.
background image
Types of coastal forests
7
Coral islands are formed by a combination of current and wave activities. They are
very low-lying with elevations of 3-5 m asl (Solomon & Forbes, 1999). The substrate
is ill-consolidated coralline material of sand and gravel, piled up over a reef platform
(Mueller-Dombois & Fosberg, 1998). Coral islands show variations in the soil
substrate. The inner or lagoon beach is sandy with the interior having higher humus
content. At the outer or ocean beach, the substrate consists of broken coral rocks,
gravel and coarse sand. Among the Pacific Islands, Tuvalu, Kiribati, Tokelau and
Marshall Islands are true atolls, while the Federated States of Micronesia and Cook
Islands are volcanic islands with atolls (Ellison, 2008).
Unlike continental islands which have a full or partial complement of plant species
of the continent before they became isolated, oceanic islands such as atolls are
formed without plant life (Gillespie, 2007). As such, coral islands do not have much
topographical features and they harbour relatively few plant species with little
endemism.
The vegetation of coral islands is essentially the same as strand vegetation of
beaches and dunes. In the Pacific, herbaceous cover of creeping plants of Ipomoea
pes-caprae
,  Canavalia rosea and Wedelia biflora are found, including sedges and
grasses at the high tide level (Mueller-Dombois & Fosberg, 1998). Further inland,
shrubs of Scaevola taccada,  Pandanus tectorius,  Pemphis acidula and Hibiscus
tiliaceus  
occur alongside trees of Barringtonia asiatica,  Terminala cattapa,
Calophyllum inophyllum and Casuarina equisetifolia. In the Maldives, tree species
found include Terminalia cattapa,  Hibiscus tiliaceus,  Thespesia populnea,
Calophyllum inophyllumPemphis acidula, Barringtonia asiatica, Pongamia pinnata
and Scaevola taccada (Jagtap & Untawale, 1999).
Low-lying coral islands on the rim of atolls are perceived as fragile ecosystems
that are particularly vulnerable to the impacts of sea-level rise. Anticipated effects
of sea-level rise are shoreline erosion, tidal inundation and salt water intrusion (e.g.
Mimura, 1999; Wong, 2003; Gillespie, 2007). Other coastal hazards include damage
by winds, waves and flooding during tropical cyclones (Solomon & Forbes, 1999).
For many people, coral islands surrounding lagoons are the perfect conditions for
an ideal tourist destination (Wong, 2003). Attractions are full privacy, all-year
sunshine, warm water, white sandy beaches and coral reefs. Besides sun, sea and
sand, one can also experience sunrise and sunset. The Maldives have developed the
one-island one-resort concept for small islands (Naseer, 2007). When an island is
developed as a resort, the whole reef ecosystem surrounding the island effectively
comes under the jurisdiction of the resort’s management. Besides tourism, fishing
is another important industry of coral islands. Activities include offshore and near-
shore reef fishing.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
8
Fig. 1. Mangrove forest of Rhizophora species fringing the banks of a creek
K. Tsuruda
Fig. 2. Typical sandy beach and dune strand vegetation in the tropics
  K.H. Tan
background image
Natural hazards affecting coastal forests
9
Manual on Guidelines for Rehabilitation of Coastal Forests, H.T. Chan & S. Baba, 2009; p. 0–00
2.1  Tsunamis
Tsunamis are series of waves caused by a large displacement of the ocean bed due
to an earthquake or volcanic eruption (King, 2008). The effects of tsunamis can be
devastating due to the immense volume of water and energy involved. It has been
recognised as one of the deadliest natural hazards (Osti et al., 2008).
In the deep ocean, tsunami waves can travel at speeds of more than 750 kph, with
wave heights of less than a metre (Solomon & Forbes, 1999). However, when they
approach shallow waters, they slow down and increase in height dramatically. This
effect is more pronounced on gradual and shallow shores (Wells et al., 2006).
Tsunamis can cause substantial damage to locations protected from wind-generated
waves, as they can accelerate through channels and inlets, rapidly increasing in
height. When reflected by obstacles, they can also travel in different directions.
The 2004 Indian Ocean tsunami caused severe economic and ecological damage to
13 countries in Asia including Africa (Kathiresan & Rajendran, 2005; Chandrasekar
& Ramesh, 2007; Osti et al., 2008). The sea waves were generated by a massive
earthquake in the ocean bed that measured 9.3 on the Richter scale. Located close
to northwest coast of Sumatra, the epicentre of the earthquake (3.7ºN, 95ºE)
generated waves that travelled in all directions with speeds up to 900 kph. The
gigantic waves killed more than 200,000 people, made about two million people
homeless and resulted in property loss of US$ 6 billion.
The following are descriptions of the disastrous effects of the 2004 tsunami on
coastal areas of five countries bordering the Indian Ocean:
Indonesia
With the earthquake epicentre less than 40 km from the northwest coast of Sumatra,
Indonesia was the worst affected (Srinivas & Nakagawa, 2008). Extending 1-2 km
inland, some 600 km of the coast of Sumatra were damaged (Shofiyati et al., 2005).
In areas with flat topography such as Banda Aceh, the width of the corridor reached
4 km inland. The city was one of the worst hit areas with 74% of 3,860 ha of
settlement area destroyed. Besides the massive human toll of more than one million
killed or displaced, the economic and environmental damage was extensive. Coral
Chapter 2
NATURAL HAZARDS AFFECTING
COASTAL FORESTS
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
10
reefs, mangroves, coastal forests, agricultural crops and aquaculture ponds were
adversely affected. The total area destroyed in Sumatra was estimated at 120,300
ha, of which 22% was settlement and 28% was agricultural land. In the Province
of Aceh, the total area of mangroves damaged was estimated at 32,000 ha with 15
districts and towns affected (Wibisono & Suryadiputra, 2006).
Damage to coastal vegetation in Aceh occurred at two stages (Wibisono &
Suryadiputra, 2006). The first stage was caused by the energy of the tsunami, which
directly struck the coast, and destroyed mangroves and other coastal forests including
cash crop plantations. This happened extremely fast and the coastal vegetation was
damaged instantly with trees uprooted or branches of trees torn off by the brutal
force of the waves (Fig. 3). The second stage was caused by the inundation of sea
water brought by the tsunami. The saline soils gradually killed the coastal vegetation
as can be seen by the withering of leaves, crown die-backs and standing dead trees
(Fig. 4).
Thailand
Much of the impact on Thailand was along the Andaman coast, affecting the coastal
provinces of Phuket, Phang Nga, Krabi, Ranong, Trang and Satun (Harakunarak &
Aksornkoae, 2005). The tsunami killed at least 5,300 people, affected 490 fishing
villages and left tens of thousands homeless. Damage to mangrove forests was
considerably less than in other countries, with less that 1% affected (Srinivas &
Nakagawa, 2008). Mangrove forests in Phang Nga significantly mitigated the impact
of the tsunami. They suffered damage at the seaward fringe, but reduced the tsunami
wave energy and provided protection to the mangrove forests further inland.
Paphavasit et al. (2007) reported that only 390 ha of mangrove forests in Thailand
were impacted by the tsunami. Mangrove forests in Phang Nga were slightly
damaged with only 90 ha in Ranong severely damaged. The area impaired was
relatively small when compared with other coastal ecosystems such as coral reefs
(690 ha) and sandy beaches (990 ha).  The most severely affected beach forests
were in Ranong and Phang Nga. Beach resorts at Khao Lak were badly damaged
(Fig. 5).
Sri Lanka
The f irst wave reached the east coast of Sri Lanka about 1.5 hour after the
earthquake, with a surge height of 5.5-6.5 m (Srinivas & Nakagawa, 2008). Over
two-thirds of the 12 districts were affected. The impact was not uniform due to
varying topography and bathymetry. The presence of houses and other buildings at
the sea-front increased the overall damage and destruction to infrastructure and
property.
background image
Natural hazards affecting coastal forests
11
The Maldives
Many of the coral islands of the Maldives were in the direct path of the tsunami
about three hours after the earthquake (Srinivas & Nakagawa, 2008). The low human
casualty was attributed to protection by the surrounding reefs. Most of the damage
was on coastal infrastructure including villages (Fig. 6), harbours and resorts. There
was some damage to coastal vegetation but beach erosion and sea water intrusion
were extensive. The tsunami displaced more than 10,000 people with three islands
totally evacuated (Naseer, 2007). Economic sectors adversely affected were tourism,
fisheries and agriculture.
Peninsular Malaysia
Although located close to the epicentre of the tsunami, Peninsular Malaysia was
shielded from the initial waves by Sumatra and was only impacted by reflected waves
(Tan & Ong, 2008). Whilst there was some loss of lives and damage to property,
all mangrove forests remained intact. The secondary waves only arrived after the
direct waves hit the Andaman coast of Thailand farther north. As such, the waves
were mild and resulted in minor damage in the north-western coast of the peninsula.
Following the 2004 Indian Ocean tsunami, two more tsunamis occurred. They
affected Java in 2006 and Solomon Islands in 2007 (Fig. 7) with estimated death
tolls of 800 and 50, respectively (Osti et al., 2008). Several years prior to the Indian
Ocean tsunami were the tsunamis of Pakistan in 1999 and Papua New Guinea in
1998.
2.2  Tropical cyclones
Tropical cyclones are formed between latitudes of 10º and 25º, and they differ from
temperate cyclones by being seasonal and having smaller whirlwinds (Mueller-
Dombois & Fosberg, 1998). They are called hurricanes when wind speeds exceed
64 knots. Hurricanes are called typhoons in countries such as Guam, Taiwan,
Philippines and Japan.
Cyclones are intense atmospheric depressions in which the winds whirl around a
small calm ‘eye’ (BPA, 1999). In coastal areas, cyclones bring the hazards of large
waves and storm surges in addition to strong winds and torrential rain. The intense
winds of cyclones are capable of generating very high seas. A temporary rise in
the sea level is known as a storm surge. The major part of the surge is usually caused
by strong onshore winds which exert a stress on the sea surface, causing the water
to accumulate. As a cyclone moves into shallow coastal waters, the near-shore bed
and coastline modify the surge, resulting in a substantial amplification of its height.
The great loss of human lives due to cyclones has often been a result of high storm
surges that led to drowning.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
12
The large waves that accompany cyclones can cause severe damage to coastal areas
(Coch, 1994; BPA, 1999). The extent of erosion depends on the storm surge at the
time of greatest wave attack. High water levels allow large waves to reach the dunes
and cause erosion as sand is moved offshore by the backwash of breaking waves.
Cyclones can substantially erode beach and dune systems and can wreck
infrastructure if they are located too close to the beach. Strong winds can damage
dune vegetation and expose the sand to wind erosion. Where sand is permanently
lost, the beach and frontal dunes become susceptible to erosion.
The following are descriptions of the impacts of cyclones on coastal areas of
Australia, Bangladesh and Myanmar:
Cyclone Winifred hit the coast of Queensland, Australia, from 29 January to 1
February 1986 (BPA, 1986). With winds gusting up to 200 kph, the cyclone
generated waves of 1.5 m and a storm surge of 1.8 m. No human death and
significant loss of property were report except for beach erosion and the over-
topping of frontal beach ridges in some areas.
Cyclone Larry lashed the Queensland coast 60 km south of Cairns in the morning
of 20 March 2006 with wind up to 300 kph (Williams et al., 2007). Although there
was damage to buildings, forests and cash crops, there was no loss of human lives.
Commercial, recreational and naval vessels in the port of Cairns were protected
from the destructive winds by docking in the sheltered creeks of the Trinity Inlet
mangroves.
Cyclone Sidr hit Sundarban in Bangladesh on 15 November 2007 (Akhter et al.,
2008). With heavy rain, winds of 220 kph and tidal surge of 3-4 m, the cyclone
caused serious damage to forest vegetation, wildlife and infrastructure in the south-
eastern part. Total forest area damaged was 133,000 ha or 22% of Sundarban. Forests
of  Sonneratia apetala were highly affected while those of Heritiera fomes and
Excoecaria agallocha were moderately affected. Slightly affected areas were along
river banks and in the northern part of Sundarban which are dominated by
Excoecaria agallocha.
Cyclone Nargis (Fig. 8) slammed Myanmar from 2-3 May 2008 with gushing winds
of 190-230 kph and waves up to 3.5 m, causing severe damage to the Ayeyarwady
delta (Than, 2008). The official death toll was 77,700 with 55,900 reported missing.
Due to the immense magnitude of the cyclone and associated tidal surges, most of
the mangrove forests in the delta were destroyed, especially in the core areas. The
extent of natural forests and plantations damaged in the Ayeyarwady and Yangon
Divisions was 14,000 ha and 21,000 ha, respectively. Physical damage to mangrove
forests included uprooting of trees, damage to crowns and branches, and crown
defoliation. Damaged forests in some areas of the core zone have yet to recover as
the cyclone adversely affected the flora and fauna. The broken forest canopy
background image
Natural hazards affecting coastal forests
13
encouraged colonisation of invasive light-demanding plant species such as Acanthus
ilicifolius
Phoenix paludosa and Acrostichum aureum. New nesting mounds of the
crocodile (Crocodylus  porosus) were found in the mangrove plantations where it
has never come to nest, as their natural nesting sites have been destroyed.
2.3  Coastal erosion
Mangrove forests are stable, accreting or eroding (e.g. Chan et al., 1993; Giesen et
al
., 2007). An accreting mangrove shore typically has a low crop of pioneer species
of  Avicennia moving seawards as the plants colonise the newly formed mud flats.
A stable shore is one that is neither accreting nor eroding. An eroding shore is
characterised by the general lowering of the near-shore prof ile, formation of
retreating scarps due to scouring of mangrove substrate (Fig. 9), collapsing of
mangrove trees (Fig. 10) and deposition of sand cheniers (Fig. 11). Comprising
mostly shell fragments, these cheniers are mobile and highly abrasive, and can cause
trees to die. The lowering of the shore profile leads to the generation of strong wave
actions which accelerate the erosion process.
Globally, retreating coastlines have been reported to exceed advancing coastlines
(Bird, 1985). About 20% of the world’s coastlines are sandy; of these, more than
70% experienced net erosion over the past few decades, less than 10% showed
accretion, and the remaining 20% was stable. There is increasing evidence that
coastal erosion is an escalating environmental threat of global concern. Factors
influencing coastal erosion are natural or human induced. Climate change and sea-
level rise are seen as major factors causing coastal erosion.
It is anticipated that the problem of coastal erosion would be most severe for low-
lying and small coral islands. The causes of beach erosion are increased wave energy,
interruption to littoral transport, deprivation of sediment input, human activities and
sea-level rise (Bird, 1996). Human activities which contribute to shoreline erosion
include mining of beach sand, poorly designed seawalls and revetments, and
destruction of coastal vegetation.
Measures of shore protection to combat coastal erosion are well known (Ghazali,
2006). They include hard engineering structures such as seawalls, groins and
breakwaters. Of the soft engineering measures, beach nourishment is most widely
practised. The construction process involves dredging, transport and placement of
sand onto the eroding beach. It is considered semi-permanent and requires periodic
replenishment of sand.
The following are descriptions of the extent and severity of coastal erosion in several
countries of South and Southeast Asia:
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
14
Thailand
Coastal erosion in Thailand has intensified during the past decade (Thampanya et
al.
, 2006). The coastline of the Gulf of Thailand in the east was more dynamic than
the Andaman coastline in the west. Erosion rates were 3.6 and 2.9 m per year versus
accretion rates of 2.6 and 1.5 m per year, respectively. It was observed that areas
with mangroves had less erosion while accretion occurred at sheltered river mouths
and in bays. Erosion was severe in areas with extensive shrimp farms (Fig. 12).
Erosion of the Bang Khun Thien mangroves in the Gulf of Thailand has been
attributed to the construction of coastal dikes and dams, and to local subsidence
due to ground water withdrawal (Winterwerp et al., 2005).
Sri Lanka
Sri Lanka’s coastline is retreating with the problem most severe in the west and
southwest (Samaranayake, 2007). The degree of erosion varied between locations
with maximum rates of up to 12 m per year.  The average rate was 0.5 m per year.
In some areas, the rate of retreat has increased due to human activities.
Peninsular Malaysia
In Peninsular Malaysia, the problem of coastal erosion was realised since the 1980s.
A national coastal erosion study was conducted to assess the severity of coastal
erosion, to map the locations of eroding shores and to recommend remedial
measures (EPU, 1986). Erosion was categorised as critical, significant or acceptable
(Table 5).
Table 5. Classification of coastal erosion in Peninsular Malaysia (EPU, 1986)
Category of erosion
Description of category
Critical
Eroding shoreline is in a state where shore-based facilities
and infrastructure are in immediate danger of collapse or
damage
Significant
Shoreline is eroding at a rate whereby public property and
agriculture land of value will become threatened within 5-
10 years unless remedial action is taken
Acceptable
Shoreline is experiencing erosion but with no or minor
consequent economic loss if left unchecked
Critically eroding areas were reported to be 131 km or 41% of the total coastline
in 1986 (EPU, 1986). A follow-up study conducted in 2006 by the Drainage and
background image
Natural hazards affecting coastal forests
15
Irrigation Department showed that the problem got worse with 256 km or 78% of
the total coastline experiencing critical erosion.
Once erosion threatens urban and agricultural property, hard engineering structures
such as rock and concrete revetments are constructed (Fig. 13). Typically constructed
from quarry rocks or concrete units, these seawalls are constructed parallel to the
shoreline forming a barrier between the coast and the sea (Ghazali, 2006). Although
they prevent further loss of landward material, reflected waves cause scouring at
the toe of the seawall. This eventually lowers the shore profile and generates stronger
wave actions. In recent years, sand-filled geotubes have been constructed in some
near-shore areas to protect against coastal erosion (Fig. 14). These breakwaters
create a calmer wave environment at the leeward side for gradual build-up of
substrate which is conducive for natural regeneration of mangroves.
Erosion affecting mangrove areas in Peninsular Malaysia is often associated with
the construction of coastal bunds to prevent seawater ingression and to divert
freshwater for agriculture (Chan et al., 1993). Of the west coast states, coastal
erosion is the most severe in Selangor as much of the coastline has been bunded
for agriculture and industrial development.
2.4  Sea-level rise
Climate change refers to the increase in global mean temperature leading to sea-
level rise (Wong, 2003). The effects of sea-level rise include accelerated coastal
erosion and more extensive flooding of low-lying coastal areas. The severity of
coastal storms is expected to increase in some tropical areas. Small and low-lying
atoll nations in the Pacific and Indian Oceans will be most vulnerable to sea-level
rise (Woodroffe, 2008). Already these islands are already experiencing inundation
during the highest tides and flooding during storms events. With sea-level rise,
inundation will be exacerbated as sea-level rise of atolls is comparable to the global
average rate of 1.4 mm/yr (Church et al., 2006).
Ong and Tan (2008) asserted that mangroves have survived sea-level changes
through geological time. The difference now is that man-made barriers along the
coast will prevent mangroves from migrating inland, so a significant reduction in
the area of mangroves may be expected. Even so, the expected loss of mangroves
to sea-level rise in the next 50 years is not expected to be anywhere close to the
loss of mangroves due to alienation in the past 50 years.
In response to sea-level rise, the Inter-governmental Panel on Climate Change
(IPCC) proposed three adaptation strategies (IPCC, 1990). They are: 1) retreat and
resettle inland; 2) continue occupancy but with some adjustments; and 3) protect
using both hard structures and soft measures.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
16
Fig. 3. Mangrove trees at Aceh torn off or uprooted by the 2004 tsunami (L)
Fig. 4. Standing dead mangrove trees at Aceh after the 2004 tsunami (R)
T. Miyagi
T. Miyagi
Fig. 7. House in Solomon Islands damaged by the 2007 tsunami (L)
Fig. 8. Cyclone Nargis that hit Myanmar in May 2008 (R)
T. Hiraishi
M.M. Than
Fig. 5. Beach chalets in Thailand damaged by the 2004 tsunami (L)
Fig. 6. Village in the Maldives damaged by the 2004 tsunami (R)
S. Yamagami
S. Yamagami
background image
Natural hazards affecting coastal forests
17
Fig. 9. Retreating scarps formed due to scouring of mangrove substrate (L)
Fig. 10. Collapsing of mangrove trees and deposition of sand cheniers (R)
H.T. Chan
H.T. Chan
Fig. 11. Cheniers of abrasive shell fragments along eroding shores (L)
Fig. 12. Severe coastal erosion threatening shrimp farms in Thailand (R)
S. Havanond
V. Jeyanny
Fig. 13. Rock revetments constructed to safeguard against coastal erosion (L)
Fig. 14. Sand-filled geotubes constructed to protect eroding shores (R)
H.T. Chan
Raja Barizan
background image
background image
Protective roles of coastal forests
19
Manual on Guidelines for Rehabilitation of Coastal Forests, H.T. Chan & S. Baba, 2009; p. 0–00
3.1  Overview
A technical workshop on Coastal protection in the aftermath of the Indian Ocean
tsunami: What role for forests and trees? 
was convened by FAO in Khao Lak,
Thailand from 28-31 August 2006. The objective of the workshop was to improve
understanding of the role of coastal trees and forests in protecting populations and
assets from natural hazards, including not only tsunamis but also cyclones, erosion,
and wind and salt spray. The workshop brought together the best available knowledge
and experience to give a clearer picture of the roles that forests and trees play in
protection against natural hazards. Conclusions of the FAO workshop (Braatz et al.,
2007), which are considered the most authoritative statements on the protective
functions of coastal vegetation, were:
y Coastal forests and trees can, under certain conditions, act as bio-shields to
protect lives and valuable assets against coastal hazards, including: tsunamis,
cyclones, wind and salt spray, and coastal erosion.
y The degree of protection offered by coastal bio-shields depends on a number
of variables, including characteristics of the hazard itself (e.g. type, force,
frequency); features of the site (e.g. bathymetry, coastal geomorphology); and
characteristics of the bio-shield (e.g. type of forest/tree, width, height and
density of the forest).
y Care must be taken to avoid making generalisations about the protective role of
forests and trees based on evidence from one or a few areas; the many factors
that influence the protective role of forests/trees must be understood and taken
into consideration before lessons can be learned and applied elsewhere.
y Coastal forests and trees are not able to provide effective protection against
all hazards (e.g. extremely large tsunami waves, flooding from cyclones and
certain types of coastal erosion); provisions for other forms of protection and
(in extreme events) for evacuation must be relied upon. Care must be taken
not to create a false sense of protection against coastal hazards.
y The importance of incorporating coastal protection as an integral part of
coastal area planning and management is recognised.
y Options for protection include soft and hard solutions, and a hybrid of the
two. If none of these is appropriate and viable, it may be necessary to zone
coastal land-use to prevent (further) settlement and construction of valuable
assets in the vulnerable zone.
Chapter 3
PROTECTIVE ROLES OF COASTAL FORESTS
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
20
y It is important to match species with the site in order to avoid high mortality
and low performance of the planted trees. Some forest types and tree species
cannot survive or thrive in areas exposed to specific coastal hazards. They
are not candidates for protective measures.
y Development of bio-shields is not possible in all situations owing to inter
alia biological limitations, space constraints, incompatibility with priority
land-uses and prohibitive costs.
y The level of knowledge and understanding of the functions of forests and trees
in coastal protection is still insufficient. There is a lack of multi-disciplinary
research in this field. Specific areas needing further attention include research
in non-mangrove coastal forests, collection of data, and development of
models on interaction between physical and ecological parameters.
y There is a need to recognise that many years are required to establish and
grow bio-shields to a size and density that could offer protection against
coastal hazards.
y Considerable research and field initiatives related to forests and coastal
protection have been carried out over the past several years; they provide a
useful foundation for further work to improve understanding of the protective
role that forests can offer.
Based on the impacts of past tsunamis, Harada and Imamura (2005) reviewed the
mitigation effects of coastal forests. According to them, the four main protective
functions of coastal forests are: 1) Reduce damage by stopping drifts and boats
carried by a tsunami; 2) Reduce the overall tsunami energy; 3) Form sand dunes
that provide protection from tsunamis as well as high waves; and 4) Catch persons
carried back by a tsunami to the sea. However, they cautioned that the protective
functions of coastal forests would be destroyed if the tsunami waves exceed 4 m in
height.
3.2  Mangrove forests
Mangroves are considered as natural barriers protecting the lives and property of
coastal communities from storms, cyclones, flooding, and coastal erosion (Walters
et al., 2008). This remains a principal reason for planting mangroves along many
low-lying coasts. Construction of engineering structures such groins and breakwaters
to protect the coastline are expensive and may not be as effective.
Areas with mangroves sustained much less damage from the 2004 Indian Ocean
tsunami than areas where mangroves have been removed and where coastal
development has reached the seafront areas (e.g. Kathiresan & Rajendran, 2005;
Danielsen  et al., 2005). Mangrove deforestation compounded the effects of the
background image
Protective roles of coastal forests
21
tsunami. These reports albeit anecdotal have been supported by evidence of satellite
images taken before and after the tsunami. Results showed that areas with mangroves
or tree cover were less susceptible to tsunami damage. Mangrove vegetation is
considered more effective in mitigating the impacts of tsunamis than other coastal
vegetation.
Although the 2004 tsunami had severe impacts on affected coasts, loss of human
lives and the degree of damage to property and infrastructure were less in places
with healthy mangrove or coastal forests, such as the Andaman and Nicobar Islands
and parts of Tamil Nadu in India (Osti et al., 2008).
Despite some controversy over whether the presence of mangroves saved lives during
the 2004 tsunami, Wolanski (2006) concluded that mangroves and other coastal
forests do provide tangible coastal protection to the extent that the establishment
of coastal green belts as buffers against storm and tsunami events is justified.
The protective role of planted mangroves in dissipating wave actions has been
reported (e.g. Mazda et al., 1997; Kogo & Kogo, 2004; Wolanski & Richmond,
2008). In the district of Thai Thuy, Vietnam, a seaward belt of Kandelia candel trees
planted at close spacing was established. Six years after planting, a 1 m wave
entering the forest was reduced to 0.05 m at the shoreline. Without the sheltering
effect of the planted mangroves, the resultant waves would be 0.75 m.
Studies have shown that for mangroves and other coastal forests to effectively buffer
against storm surges and tsunamis, they should be at least 100 m in width (Mazda
et al., 1997) or have 400 trees per 10 m of shoreline in density (Hiraishi, 2008).
However, it has been envisaged that once the height of waves impacting a coast
reaches 2 m or more, the forest will usually fail, and the trees themselves become
part of the debris that causes damage further inland (Hanley, 2007).
Cochard (2008) supported the argument that mangroves and other coastal vegetation
play a minor role in buffering against tsunami waves. Whether or not vegetation
does provide protection depends on many factors, including stand size, density,
species composition, structure and homogeneity. The most important predictor
variables of the tsunami hazard are distance from the tsunami source and coastal
topography, in particular near-shore bathymetry. In locations, far from the tsunami
source, coastal vegetation probably provided some protection. In many other
locations, however, the vegetation provided no protection. In some cases, they may
even have aggravated the problem e.g. by contributing to flow debris and by
channelling water flows. The establishment of tsunami greenbelts should not be
treated as an alternative to early warning systems. Greenbelts may only be
considered as economical and multi-functional means to provide relative hazard
protection for material assets such as infrastructure and agriculture.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
22
Since the 2004 tsunami, the general picture emerging is that mangroves are not the
main factor influencing the extent of damage on the coastline (Wells et al., 2006).
Near-shore bathymetry and coastline prof ile are probably the key factors
determining the force of tsunami waves at any particular location. Shores adjacent
to deep water tended to be less affected than those next to shallow and gradually
sloping shelves. The shape of the coastline is another factor, with headlands
providing protection while bays and inlets act as funnels, restricting and focusing
the force of the waves. More research is required before it will be possible to predict
where, and in what way, mangroves will help to reduce the impact of a tsunami.
The role of mangroves in protecting the shoreline from coastal erosion remains
unclear. Blasco et al. (1996) pointed out that mangroves do not prevent coastal
erosion but their elaborate root structures are likely to slow down the process
considerably. Although mangroves can provide limited protection against erosive
forces, Hanley et al. (2008) emphasised that mangroves typically colonise sheltered
areas where fine sediments are deposited by coastal processes. Once established,
they can enhance the process of sedimentation by increasing the rate of deposition.
Mangroves do not, however, initiate sedimentation and are not able to colonise or
persist at high energy shorelines. Natural hazards such as storms, cyclones, floods
and tsunamis create severe erosion and in many cases mangroves can reduce the
scale of these impacts. However, if episodes are frequent enough then the coastline
will recede and eventually the mangroves will disappear.
3.3  Other coastal forests
It has been suggested that pure stands of Casuarina  equisetifolia trees with little
undergrowth provide limited resistance against the hazardous tsunami waves
(Cochard  et al., 2008). The dense, multi-layered strand formation of Barringtonia
asiatica
,  Pandanus tectorius and Scaevola taccada probably provides better
protection. In many locations, strand vegetation has been replaced by coconut groves
which afford the least physical protection.
Compared to mangrove forests, strand vegetation may not provide adequate
protection against tsunami (Kathiresan & Rajendran, 2005). Field observations
following the 2004 tsunami showed that most of the beach and dune vegetation was
affected with browning of canopies and trees shedding their leaves. However, they
would hold good as wind-breakers during coastal storms.
Strand vegetation has been reported to provide protection of beaches and dunes
against coastal erosion. For example, trees of Scaevola taccada serve as a protective
barrier for the beaches of Kerala in India (Sundaresan, 1993). Natural vegetation
belt of Scaevola taccada and Pandanus odoratissimus, with their masses of exposed
roots and branches, have been effective in reducing wave energy and coastal erosion
on Bintan Island in Indonesia (Wong, 2003).
background image
Guidelines for rehabilitation of coastal forests
23
Manual on Guidelines for Rehabilitation of Coastal Forests, H.T. Chan & S. Baba, 2009; p. 0–00
4.1  Overview
Concepts and rationale
Rehabilitation of coastal forests can be defined as the act of partially replacing their
structural or functional characteristics that have been diminished or lost (Field,
1998a). This would mean re-establishing some of the ecological attributes.
Restoration of coastal forests is the act of bringing them back, as nearly as possible,
to their original condition. By implication, all the key ecological processes and
functions including all the former biodiversity are re-established (Wells et al., 2006).
The creation of plantations of a few coastal species does not equate to restoration.
As restoring a coastal forest ecosystem to its original undisturbed condition is not
realistic, rehabilitation is the preferred term to use.
The shortage of productive land in developing countries has resulted in coastal
forests being converted for development.  The rapid alienation of coastal forests
has prompted a worldwide movement to plant new forest areas (Field, 1998a).
Another impetus behind the rehabilitation of coastal forests is the spectacular rise
of environmental consciousness in recent decades. The devastation of coastal areas
by the Indian Ocean tsunami in December 2004 and cyclone Nargis in May 2008
has presented yet another rationale for establishing plantations of coastal forests
for protection against natural hazards.
If the rationale of rehabilitation is to establish protective coastal belts to safeguard
against natural hazards, there are no valid reasons for planting coastal species at
fixed spacing along lines as traditionally done in plantation forestry. Other options
such as cluster planting and phased planting can be tried out.
Cluster planting may be favoured in heterogeneous habitats (e.g. seaward tidal flats)
where some sites are unsuitable for rehabilitation. Efforts should focus on
establishing clusters of trees in favourable sites. Over time, these clusters would
establish themselves and serve as mother populations to seed up the remaining sites
through natural regeneration. The concept is essentially planting to assist in the
natural recovery process.
Phased planting may work well in difficult habitats with harsh environmental
conditions (e.g. coastal dune formations). Initial efforts will focus on planting
Chapter 4
GUIDELINES FOR REHABILITATION OF
COASTAL FORESTS
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
24
pioneer herbaceous plant species to stabilise the site and to ameliorate site
conditions. The planting of woody tree species will only commence after the site
has stabilised and conditions improved.
Finally, if all initial trials failed in a given coastal area, the best option would be to
do nothing and allow the shore to change naturally without intervention. As shore
changes are usually cyclical, the site conditions may gradually improve to levels
where rehabilitation becomes feasible.
A report by the Environmental Justice Foundation has rightly asserted that mangrove
forests may recover without active rehabilitation efforts, once stresses to them have
been removed (EJF, 2006). Rather than to launch straight into massive replanting
programmes, at high cost and with a low probability of success, it may be far more
sensible for governments of tsunami-affected countries to concentrate on the natural
regrowth and recovery of remaining mangroves. Undoubtedly, this advice also
applies to other coastal forests.
Rehabilitation efforts
The two main criteria for assessing the success of a coastal rehabilitation programme
are the effectiveness and efficiency of the planting (Field, 1998b). The former can
be considered as the closeness to which the new mangrove forest meets the original
goals of the planting programme. The latter can be measured in terms of the amount
of labour, resources and material that were used. In most cases, the effectiveness
and efficiency of rehabilitation are not always quantified.
With every rehabilitation effort of coastal forests, there is always a high degree of
uncertainty over the success of meeting its objectives (Yap, 2000). The level of
difficulty varies with the different forest types and site conditions, and so does the
associated expenditure in terms of manpower and financial resources. It is generally
acknowledged that mangroves are easier to rehabilitate compared to other coastal
forests.
Following the aftermath of the Indian Ocean tsunami, governments of countries in
South and Southeast Asia have pledged their support for mangrove rehabilitation
(Check, 2005). Malaysia has allocated $25 million to replant 4,000 ha of mangroves.
Indonesia has pledged $22 million and has already planted 300,000 seedlings in
Aceh. The Thai government has expressed its support for mangrove and coastal
forest rehabilitation. The government of India has pledged $8 million to supplement
an on-going programme to rehabilitate mangroves damaged by cyclones.
As many as 124 international NGOs participated in the reconstruction and
rehabilitation of Aceh and Nias (Wibisono & Suryadiputra, 2006; UNEP, 2007).
About 20 of them were involved in coastal rehabilitation programmes. They included
background image
Guidelines for rehabilitation of coastal forests
25
Oxfam International, Islamic Relief, Mercy Corps, GTZ, FAO and Wetlands
International. More than 430 national NGOs participated but less than 20% were
involved in coastal rehabilitation. In Aceh, over 10,000 ha of mangroves have been
planted by the Board of Rehabilitation and Reconstruction of the Ministry of
Forestry in areas affected by the tsunami (Triswanto, 2006).
Elsewhere in the region, post-tsunami projects were also implemented. An example
is the mangrove rehabilitation project in Sri Lanka and Thailand (Qureshi, 2008).
Funded by the Ministry of Environment of Spain, the project was implemented by
IUCN from September 2005 to December 2007. In Phang Nga, more than 200 ha
of mangroves damaged by the tsunami have been rehabilitated by the Department
of Marine and Coastal Resources (DMCR) in collaboration with local residents
(Paphavasit  et al., 2007). DMCR also planted 3,000 seedlings of Cocos nucifera,
Casuarina equisetifolia, Barringtonia asiatica and Pandanus odoratissimus.  In
Peninsular Malaysia, although hardly affected by the tsunami, about 150 ha of
mangroves and 18 ha of beach forests have been planted in the various states by
the Forestry Department in 2005 (Mohd Ridza, 2006).
4.2  Mangrove forests
Rationale for rehabilitation
Mangroves have been planted for various purposes including: a) wood production
to support commercial or small-scale forestry; b) shoreline and storm protection
for coastal settlements; c) fisheries, aquaculture and wildlife enhancement; and d)
ecological restoration (Field, 1996; Yap, 2000; Walters et al., 2008).
Since the Indian Ocean tsunami and with more intensified coastal erosion, there is
increased interest in planting mangroves for coastal protection (Check, 2005). In
Thailand, concern over mangrove deforestation by shrimp farms has motivated many
coastal households to participate in mangrove rehabilitation programmes (Barbier,
2006).
In the past, mangroves are considered easy to rehabilitate. Viviparity of their
seedlings enables direct planting of propagules which are available in abundance,
and planted seedlings often have good survival and growth rates. Reforestation
programmes have been successful in many countries of the Asia-Pacific region
(Field, 1996).
Recently, many post-tsunami mangrove rehabilitation projects have failed or
achieved limited success as exemplified by those implemented in Aceh (e.g. Check,
2005; Wibisono & Suryadiputra, 2006; UNEP, 2007; Hanley et al., 2008). Lessons
learnt from these failed projects included planting too soon, wrong choice of species,
planting in the wrong places, and the lack of monitoring and tending after planting.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
26
Erftemeijer and Lewis III (1999) emphasised that during low tides, the intertidal
mud flats serve as important feeding grounds for migratory shore birds and as
habitats for local people to collect bivalves and crabs. Any attempts at mangrove
restoration on mud flats would represent a form of habitat conversion.
Past attempts in planting mangroves on tidal flats to mitigate coastal erosion in
Malaysia and Thailand have failed. In Selangor, Malaysia, Chan et al. (1988)
reported that several planting trials of Avicennia officinalis on an exposed mud flats
seaward of an eroding shoreline were not successful. Among the factors adversely
affecting survival and growth of mangrove plants are strong wave actions, high soil
salinity, barnacle infestation, prolonged inundation and lack of tidal flow. At Ban
Don Bay in southern Thailand, mangroves were planted on newly-formed mud flats
(Angsupanich & Havanond, 1996). Seedlings of Avicennia alba and Sonneratia
caseolaris
 died within eight months while those of Rhizophora mucronata died
within a year. Seedling mortality was attributed to severe infestation by barnacles
and frequent immersion in seawater during high tide.
Choice of species
For the rehabilitation of mangroves, the choice of species and their propagation
methods described here are by no means exhaustive. The species have been selected
because some knowledge is available on their silviculture and they have potentials
for coastal protection. The species, and their life-forms, habitat types, salinity ranges
and inundation classes are listed in Table 6.
Table 6. List of mangrove species, and their life-forms, habitats, salinity ranges
and inundation classes
Choice of species
Life-form
Habitat type
Salinity
Inundation
range (ppt)
class*
Acrostichum aureum
Fern
Back mangroves
< 15
4
Avicennia marina
Tree
Seaward shores
> 25
1
Bruguiera gymnorhiza
Tree
Central mangroves
15 – 25
3
Ceriops tagal
Tree
Central mangroves
15 – 25
3
Nypa fruticans
Palm
Riverine mangroves
< 15
5
Rhizophora apiculata
Tree
Central mangroves
15 – 25
3
Rhizophora mucronata
Tree
Banks of tidal creeks
15 – 25
2
Rhizophora stylosa
Tree
Central mangroves
15 – 25
3
Sonneratia alba
Tree
Seaward shores
> 25
1
* Refer to Table 2 for description of inundation classes
background image
Guidelines for rehabilitation of coastal forests
27
References to information of these mangrove species are mainly from Tomlinson
(1986), Kitamura et al. (1997), Duke (2006), Giesen et al. (2007), Selvam (2007)
and Hanley et al. (2008).
Acrostichum aureum
Acrostichum aureum (Pteridaceae) is a mangrove fern that grows to 4 m in height.
Stems of fronds are stout, erect and covered with large scales. Tips of fertile leaves
are rusty-brown, maturing dark brown during spore release. Spores are large and
tetrahedral in shape. Tips of sterile leaves are blunt with a short tip. Leaf venation
is net-like. It can be distinguished from Acrostichum speciosum by being taller, with
young fronds being reddish and leaves with blunt tips. In open, degraded and inland
mangrove areas that are seldom inundated, the species forms tall dense thickets (Fig.
15). The species can easily be propagated by rhizomes. Considered a weed which
stifles the regeneration of commercial tree species by foresters, eradication by
uprooting the fern is difficult as the exposed rhizomes can still sprout.
Avicennia marina
Avicennia marina (Avicenniaceae) is a tree that grows to 10 m tall and is
characterised by its pencil-like pneumatophores. The bark is smooth, grey, mottled
green and peeling in patches. Leaves are single, opposite, leathery, yellowish-green
and silver-grey below with pointed apex. The under surface of leaves has special
salt secreting glands. Flowers are small, sessile, fragrant and pale yellow. Fruits
are heart-shaped, rounded or sometimes shortly beaked and greyish with fine hairs.
It grows throughout the intertidal zones of estuaries, lagoons and backwater. It
prefers fine clay and alluvial soil, and tolerates a wide range of soil salinity. The
species can be easily propagated by propagules.  Collected from trees or from the
forest floor, propagules are soaked in brackish water to facilitate shedding of their
outer coat. When sowing in the nursery, the radicle part of the propagules is lightly
pushed into the soil. Nursery-raised seedlings of about 30 cm can be out-planted.
Bruguiera gymnorhiza
Bruguiera gymnorhiza (Rhizophoraceae) is a moderate-sized tree that grows to 15
m, occasionally up to 30 m tall. It has short buttresses and characteristic knee-shaped
breathing roots. Bark is dark grey to black and conspicuously fissured. Leaves are
simple, opposite, leathery and dark green with long leaf stalks. Flowers are single
and axillary in position. Calyx is reddish to scarlet with 10-14 pointed lobes (Fig.
16). Petals are orange-brown in matured flowers and bi-lobed with each lobe having
3-4 long bristles. Propagules are cigar-shaped, 15-25 cm in length, 2 cm in diameter,
stout with blunt apex. When mature, they are reddish-brown or greenish-red. The
species is capable of growing well in somewhat dry and well-aerated soils. It is
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
28
one of the most shade-tolerant mangrove species and seedlings may grow under a
full forest canopy. It is propagated from propagules. Direct planting of propagules
has been successful. Nursery-raised seedlings of 35 cm in height can be out-planted.
Ceriops tagal
Ceriops tagal (Rhizophoraceae) is a small tree that grows to 6 m in height. It has
short buttresses and knee-like breathing roots. The bark is pale grey to reddish-
brown, smooth in young trees and deeply fissured in old trees. Leaves are simple,
shiny, opposite and ovate. Leaves are dark green in shade and bright greenish-yellow
in full sun. Leaf apex is rounded or notched. Inflorescence is a condensed cyme
and axillary with 5-10 flowers. Calyx is deeply sunken and divided into five green
lobes. Petals are five in number and white turning brown, two-lobed and ending in
2-4 bristles. Propagules are slender and yellowish-green, warty, ribbed and widest
at the distal half (Fig. 17). Surface of the propagules is warty and ridged. Mature
propagules are recognised by their yellow collar and brownish-green hypocotyl.
Freshly plucked from mother trees or collected from the ground, they can be used
for direct planting. Nursery-raised seedlings 20 cm in height can be used for out-
planting.
Nypa fruticans
Nypa fruticans (Arecaceae) is a stemless palm with branching underground
rhizomatous roots. Growing to 10 m tall, fronds are erect and slightly recurved with
a stout stalk that is strongly flanged at the base (Fig. 18). Each frond has 100-120
leaflets with a shiny green upper surface and a pale lower surface. The midrib of
each leaflet is marked by brown scales. The species is monoecious with female
flowers forming a spherical head of congested flowers. The bright yellow male
flowers are catkins, located below the female head of flowers. The fruiting body is
a spherical aggregate of individual brown fruits which are obovate, angular and
fibrous. Each fruit contains a white, egg-shaped seed. The species is monotypic
and occurs on soft, fine-grained substrates at the upper limits of tidal waterways
where there is a regular supply of fresh water. It grows gregariously forming pure
stands. Propagation is by sowing seeds in the nursery and out-planting of seedlings
after several months.
Rhizophora apiculata
Rhizophora apiculata (Rhizophoraceae) is a large-sized tree that grows to 30 m in
height with 50 cm trunk diameter. It is characterised by the presence of stilt roots,
which are looping from the base of the trunk, and occasionally has aerial roots
emerging from lower branches. The bark is grey to dark grey and sometimes
longitudinally fissured. Leaves are simple, opposite and narrowly elliptic with fine
background image
Guidelines for rehabilitation of coastal forests
29
black dots on the under surface. The inflorescence is axillary and a two-flowered
cyme (Fig. 19). The peduncle is stout and grey. The calyx is four-lobed, greenish-
yellow inside and reddish-green outside. Petals are four in number and white.
Viviparous propagules are 25-30 cm long, greenish-brown, warty or relatively
smooth. The species can be easily propagated from propagules. Matured propagules
are characterised by a prominent red collar at the junction of the fruit and hypocotyl.
Propagules can be stored for several days by soaking in brackish water. They can
be directly planted in the field.  Seedlings can be raised in the nursery before out-
planting. After 4-5 months, seedlings of about 30 cm in height and with two pairs
of leaves can be out-planted. The survival rate of nursery-raised seedlings is higher
than those from directly planted propagule but at a higher planting cost. The species
starts producing flowers and propagules 5-6 years after planting.
Rhizophora mucronata
Rhizophora mucronata (Rhizophoraceae) is a tree that reaches 25-30 m in height.
Trees are characterised by stilt roots looping from the base of trunks. The bark is
dark grey and horizontally fissured. Leaves are single, opposite, leathery, broadly
elliptic to oblong with clear black dots on the under surface. The inflorescence is
axillary and a dichotomously branched cyme, with 4-8 flowers (Fig. 20). The
peduncle is slender, yellow and 2-3 cm long. Flowers are creamy white, fleshy and
fragrant. Calyx is deeply four-lobed and pale yellow. Petals are four in number, light
yellowish in colour with dense hairs along the margin. Viviparous propagules are
50-70 cm long, cylindrical, warty and yellowish-green. The species grows well along
creek banks in deep soft mud, which is rich in humus. It is easily propagated from
propagules. Mature propagules have a prominent yellowish collar at the junction
of the fruit and hypocotyl. They can be out-planted directly or raised in the nursery
prior to planting in the field. Growth is generally vigorous and planted trees are
reproductive 3-4 years after planting.
Rhizophora stylosa
Rhizophora stylosa (Rhizophoraceae) is a small tree with single or multiple trunks.
It grows to 10 m tall with 10-15 cm trunk diameter. The bark is smooth, reddish-
brown to pale grey and fissured. It has stilt roots with aerial roots emerging from
the lower branches. Leaves are broadly elliptic, leathery, with spots at the lower
surface and an extended pointed tip. The inflorescence is axillary, forking 3-5 times
with 5-8 bisexual flowers (Fig. 21). The four pale yellow calyx lobes, remaining
on the fruit, are re-curved. The four yellowish to whitish petals have densely woolly
margins. Each flower has eight stamens and a 4-6 mm long style. The fruit is
elongated, pear-shaped and brown when mature. Flowers and fruits are produced
throughout the year. This pioneer species grows in a variety of tidal habitats
including tidal flats and coral islands.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
30
Sonneratia alba
Sonneratia alba (Sonneratiaceae) is a tree that grows to 20 m tall. The bark is cream
to brown and smooth with fine longitudinal fissures. Arising from underground cable
roots are stout conical pneumatophores. Leaves are simple, opposite, leathery, ovate
and bear vestigial glands at the base of leaf stalks. Bisexual flowers occur either
solitarily or in groups of three (Fig. 22). The 6-7 persistent sepals are green outside
and red inside. Flowers have an attractive display of numerous long and white
stamens that soon shed following anthesis. Flowering occurs all year round. The
fruit is a flattened round berry with persistent sepals at its base and contains many
seeds. The species is a pioneer found in seaward habitats of consolidating mud and
sand. It also occurs on rocky shores and on coral islands.
Site selection and preparation
It is crucial to determine the site conditions before embarking on any mangrove
rehabilitation project (e.g. Ong, 1995; Kaly & Jones, 1998). Abiotic factors include
shore dynamics e.g. exposure to storms and wave actions; shore profile e.g. eroding,
accreting or stable; soil properties e.g. salinity and pH; amount and type of
sedimentation; frequency and degree of tidal inundation; and availability of
freshwater inputs. Biotic factors include availability and quality of planting material;
incidence of pests e.g. barnacles; and presence or absence of natural regeneration
of tree species and associated fauna.
If the conditions of a particular site are unfavourable, the best option would be to
defer planting and to select other more suitable sites. It should be emphasised that
mangroves typically colonise sheltered coastal areas with deposition of sediments
and freshwater inputs. Priority should therefore be accorded to sheltered estuaries
particularly in the enrichment of degraded forest areas. Tidal flats at the seafront
with deep mud that are exposed to the vagaries of storms and wave actions, deeply
inundated during high tide, and devoid of any life forms, should be avoided (Fig.
23). Tidal flats with some early colonising individuals of pioneer species are more
suitable for rehabilitation (Fig. 24). In cases of uncertainty, small-scale feasibility
trials to assess site suitability can be conducted. Failing which the best option would
be to do nothing and allow the shore to change naturally without intervention. Too
many attempts have failed when planting mangroves in such exposed habitats.
In the Philippines, planting of mangroves on seaward tidal flats had only 10-20%
survival (Primavera & Esteban, 2008). In former mangrove areas that have been
bunded and tidal flow restricted, it is crucial to re-establish the tidal drainage
(Wolanski & Richmond, 2008). Too often, mangrove seedlings have been planted
without re-establishing tidal flow. Where water stagnates, the seedlings invariably
stop growing and gradually die. The more successful mangrove rehabilitation
background image
Guidelines for rehabilitation of coastal forests
31
projects are those located in areas with low-energy and with an appropriate elevation
within the intertidal zone (Yap, 2000).
Following damage to mangroves of the Ayeyarwady delta in Myanmar by cyclone
Nargis in May 2008, it was reported that the damaged canopy encouraged the
colonisation of invasive light-demanding species such as Acanthus ilicifolius,
Phoenix paludosa and Acrostichum aureum (Than, 2008). These species form dense
thickets and would require site treatment prior to planting. A cost-effective technique
has been reported by Chan et al. (1987). It involved cutting lines through the thickets
using a saw-edged disc cutter before planting mangrove propagules. The competition
for light would encourage more rapid growth of the mangrove plants.
Propagation and planting
Direct planting of propagules
Direct planting of propagules is by far the most widely used technique for mangrove
rehabilitation (Chan, 1996). Its timing largely depends on the availability of
propagules and hence planting is often carried out during the fruiting season.
Gathering of fresh-fallen propagules from the forest floor is preferred as this will
ensure their maturity. The plucking of pre-dispersed propagules from mother trees
is discouraged. Not only the process is more tedious, there is every possibility that
immature propagules are collected. Only sound propagules are selected for planting
with those damaged by beetles or rough handling rejected.
Direct planting of propagules of RhizophoraBruguiera and Ceriops is simple and
can be done by untrained labourers. It involves inserting the elongated propagules
into the often soft and moist mud. The depth of planting would depend on the length
of propagules. In plantation forestry, planting is carried out along predetermined
lines and at f ixed spacing by the planting crew. Planted trees of Rhizophora
mucronata
 and Rhizophora apiculata are reproductive 3-4 years and 5-6 years after
planting, respectively. Although direct planting of Avicennia  propagules is rarely
done, techniques of broadcasting or burying propagules (several per hole) can be
tried out. For Sonneratia species, direct planting of portions of mature fruits with
enclosed seeds may be worth trying.
Planting of potted seedlings
Collected propagules are sorted to ensure that only sound ones will be potted in
the nursery. The choice of site for establishing the nursery is crucial so that the
tides inundate the potted seedlings daily. For convenient transportation of seedlings,
the nursery may be located at the planting site. Nursery seedlings require a growth
period of 5-6 months before they can be out-planted in the field. By then, they would
have acquired 2-3 pairs of leaves. Polythene bags should be removed before the
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
32
seedlings are planted.  Besides having higher survival rates, planting using potted
seedlings is an effective technique in overcoming the problems related to predation.
Potted seedlings with woody stems are resistant to both crab and monkey attack
(Chan, 1996). In view of the higher cost of planting, the use of potted seedlings
should be restricted to more problematic sites.
Planting of wildings
Natural regeneration of mangrove species is often bountiful. Wildings are readily
available in the vicinity of mother trees, can therefore be used as planting stock
for rehabilitation. The planting of bare root wildings is not recommended as survival
is low. The planting of rooted wildings has been shown to be effective (Chan, 1988;
Chan, 1996). The technique of collection is simple and essentially involves
extracting wildings of 0.5-1.0 m in height using a specially designed steel corer of
10 cm diameter. The corer is pushed into the ground in a spiral motion and then
shaken to dislodge the plug of soil carrying the wilding. Penetration is aided by
turning the two handles and by having a serrated edge at the bottom of the corer.
Collected wildings are then placed onto wooden trays and transported for planting.
Boats will be required for transporting wildings over greater distances.
Monitoring and tending
At Aceh, seedling survival of many of the post-tsunami mangrove rehabilitation
projects was very low (Wibisono & Suryadiputra, 2006; UNEP, 2007). This was
partly attributed to the lack of monitoring and tending of planted seedlings.
Rehabilitation work was considered completed as soon as the seedlings had been
planted. Neither monitoring nor tending was deemed necessary.
Monitoring and tending of mangrove plantations are crucial as they provide useful
information for future projects. Many lessons can be learnt based on the growth
performance of planted seedlings. They include site selection, choice of species,
causes of mortality, and effectiveness of silvicultural treatments such as replanting
and pest control.
Case studies
Mangrove afforestation in Bangladesh
In 1966, the Forest Department of Bangladesh initiated a mangrove afforestation
programme to protect coastal areas from cyclone damage (Saenger & Siddiqi, 1993).
Initial planting of Sonneratia apetala and Avicennia officinalis at 320 ha per year
was highly successful in protecting and stabilising coastal areas. This led to a large-
scale mangrove afforestation initiative. Funded by the World Bank, the Mangrove
Afforestation Project planted 120,000 ha of mangroves from 1980-1990.
background image
Guidelines for rehabilitation of coastal forests
33
During the cyclone of April 1991, many of the mangrove plantations were damaged.
Young plantations seemed to have suffered most. Several months later, most of the
plantations showed signs of recovery. Damage to non-mangrove trees planted on
the coastal embankments was signif icantly higher. The susceptibility of non-
mangroves to wind-throw was attributed to their less developed root systems.
Subsequently, it was acknowledged that the most significant benefit of mangrove
plantations was their ability to recover from storm damage through self-repair. The
establishment of mangrove plantations has contributed to coastal stabilisation and
protection in Bangladesh.
Post-tsunami mangrove rehabilitation in Aceh, Indonesia
According to a report by FAO, many of the post-tsunami mangrove rehabilitation
projects in Aceh were generally sub-standard due to various reasons (Hanley et al.,
2008). They include the following:
y Limited areas planted - in many cases a few hundred seedlings have been
planted in a very small area.
y Seedlings were planted too close together - distance between seedlings of 50
cm was common and there were examples of seedlings planted just 10 cm
apart.
y Seedlings were planted without removal from polythene bags - it is possible
that some plants may survive, but most plants will die.
y Poor site selection - many seedlings were planted in inappropriate sites.
y Typically, only seedlings of Rhizophora apiculata were planted. Those of
Rhizophora mucronata were also present at some sites but there was little
evidence of species being matched to sites with respect to shore elevation,
substrate type, salinity, etc.
y Often seedlings were planted among debris which damaged seedlings when
moved by the tide and freshwater flow.
y There was little or no community commitment to maintenance of the seedlings
- many NGOs undertook planting as cash-for-work schemes and were not
expected maintain the plantations.
According to UNEP (2007), 30 million mangrove seedlings covering 27,500 ha had
been planted in Aceh since the tsunami. Unfortunately, most of the mangroves were
planted in damaged pond areas and many seedlings were destroyed by the heavy
machinery used in repair work. Other mangrove planting areas were destroyed by
the construction of infrastructure, suggesting a lack of coordination among the
various actors. The need to avoid such poor planning in planting efforts is one of
the lessons learnt, the others being:
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
34
y Short-term, project-based, cash-for-work schemes in which local people
worked as paid labourers. With limited supervision, training or education,
there was little after-care of planted seedlings and mortality rates of seedlings
were high.
y With most of planted seedlings being Rhizophora  mucronata, the resulting
mangrove monocultures lack structural and taxonomic diversity and zonation,
which may render them vulnerable to environmental shocks and diseases
y Importing seeds and seedlings from Java to relieve local supply shortages
meant that many (35-50%) died during shipping, and the rest were stressed
and weakened
y The use of mature seeds and seedlings is essential to high survival rates after
planting
y The choice of site for nurseries is important to seedling production, the best
sites being tidal, flat and sheltered from the wind
y The use of growth media with little mud content causes seedlings to die
y A 1-2 month hardening period is needed before planting, during which the
seedlings are progressively deprived of fresh water and shade
y Seedlings were often planted in the wrong sites i.e. in sandy areas, in areas
prone to drying out, and in high-energy locations vulnerable to currents and
wind
y Planting in privately-owned areas without the owner’s permission may result
in the seedlings being removed later
y Various technical errors can kill or weaken seedlings, including planting at
the hottest times of day, transporting seedlings with bare roots, and planting
seedlings still in their polythene bags
y Young seedlings are vulnerable to pest attack especially by barnacles, crabs
and mud lobsters
y Seedlings need to be protected against browsing livestock
The study by UNEP (2007) concluded that key priorities were stakeholder
coordination, full long-term community participation, awareness of the correct
techniques, sites and species matching, and biological indicators. Educational and
awareness-raising activities are important, and diversification of species planted
should also be encouraged.
Another study on lessons learnt from mangrove rehabilitation efforts in Aceh was
conducted by the Wetlands International – Indonesia Programme (WIIP) jointly with
UNEP (Wibisono & Suryadiputra, 2006). It was reported that only a small fraction
of rehabilitation efforts has been successful. The rest has failed based on the low
survival rate of plants in the field.  Among the reasons given were:
background image
Guidelines for rehabilitation of coastal forests
35
y Mistakes in the selection of planting sites and unsuitable choice of plants
y Insufficient preparation and inadequate guidance
y Low capacity of human resources and limited amount of community
involvement
y No tending of the plants as rehabilitation activity is considered completed
after planting
y Emphasis was on the number of seedlings planted and not on the number
that survived
Mangrove planting projects in AcehIndonesia
WIIP has been implementing mangrove planting projects in Aceh by negotiating
agreements with villagers (Check, 2005). Villagers are committed to plant an agreed
number of seedlings they collect from the wild. In return, the programme provides
support staff and loan to enable the villagers to initiate businesses such as chicken
and goat farms. If 70% of the seedlings planted are still alive after five years, the
villagers can keep the money; otherwise they have to repay part of the loan. These
negotiated agreements encourage villagers both to plant and care for the forests,
making them more likely to survive. Villagers have planted 350 ha along 3.5 km
of the coast through these arrangements.
Post-tsunami mangrove planting in Peninsular Malaysia
The following case studies on post-tsunami planting of mangroves in Peninsular
Malaysia have been reported by Ong (2007), and by Tan and Ong (2008).
On the northwest coast of Penang, Rhizophora apiculata seedlings were planted
under an already good cover of Avicennia marina forest. Most of the planted
seedlings died probably due to inadequate light and high soil salinity. This activity
raises the fundamental question as to the purpose of planting, apart from obtaining
funds to carry out the work.
On the southwest coast of Penang, dredged spoils from earthworks carried out soon
after the tsunami, were piled on one bank of the estuary. There were not enough
culvert openings to provide the necessary hydrological circulation for the mangrove
community dominated by Avicennia marina and a patch of mangroves died behind
the bund. Again, mangrove seedlings were introduced to the dead patch of Avicennia.
As the seedlings planted were Rhizophora apiculata, most of them died. This is
another example of knee-jerk reaction by simply planting mangrove seedlings.
Another mangrove rehabilitation project was near Pulau Sayap in Kedah. Rhizophora
apiculata 
seedlings grown in PVC tubes, presumably to protect the shoreline from
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
36
coastal erosion, were planted on the mud flats seaward of an existing mangrove
forest of mainly Avicennia marina. Within weeks, most of the seedlings had
disappeared and their PVC tubes were strewn everywhere by wave actions (Fig. 25).
Subsequent attempts at planting Rhizophora mucronata seedlings in bamboo tubes
were also unsuccessful (Fig. 26). Even if waves are not a problem, mud flats are
certainly not the correct places to plant mangroves. Mangroves cannot survive on
exposed low-elevation tidal flats.
MANGREEN – Ecological mangrove restoration in India
The coastline of Tamil Nadu or Land of the Temples in southern India was hit by
the 2004 tsunami. Through the initiatives of DEEPWAVE (Initiative for the
Protection of the High Seas) and OMCAR (Organization for Marine Conservation,
Awareness and Research), the MANGREEN project was initiated (Balaji & Gross,
2006; GNF, 2007). In September 2005, Ecological Mangrove Restoration (EMR)
sites for natural and artificial regeneration were established in two fishing villages,
Keezhathottam and Velivayal, located at Agni estuary in the northern Palk Bay. These
sites have been established after careful study on soil quality, species suitability,
natural recruitment, land elevation, water sources, grazing effect and land-use. The
villagers have been recruited for excavation of water channels, fencing, seed
collection, plantation and maintenance. More than 10,000 mangrove seedlings have
been planted and 4,000 saplings have been raised in nurseries. It was reported that
nursery-raised seedlings showed higher survival rates than direct planting of
propagules.
Mangrove rehabilitation project in Kiribati
The Republic of Kiribati comprises 16 atolls with low-lying coral islands of less
than 4 m asl surrounding lagoons (Mueller-Dombois & Fosberg, 1998). The soils
are coarse textured, alkaline with pH of 8.2-8.9 and deficient in trace elements.
Principal food crops are Cocos nucifera, Artocarpus altilis, Pandanus tectorius and
Cyrtosperma chamissonis. Beach strand vegetation consists of Scaevola taccada,
Terminalia littoralis,  Calophyllum inophyllum,  Hernandia nymphaeifolia and
Thespesia populnea. Mangrove species include Rhizophora stylosaSonneratia alba,
Bruguiera gymnorhiza and Lumnitzera littorea (Fig.  27).
With support from the local Ministry of Environment, Land and Agriculture
Development, and the Ministry of Education, Youth and Sports, the International
Society for Mangrove Ecosystems (ISME) has implemented a mangrove
rehabilitation project in Tarawa, Kiribati since 2005 (Baba et al., 2008). Funded by
Cosmo Oil Company Ltd. Japan, the objectives of the project are to establish coastal
green belts especially along the banks of causeways using simple planting
techniques, to create suitable grounds for fisheries resources, and to educate school
children and youths on the importance of mangrove ecosystems.
background image
Guidelines for rehabilitation of coastal forests
37
Propagules of Rhizophora stylosa were collected locally and planted in groups of
three propagules each at close spacing of 0.5 x 0.5 m (Fig. 28). Some 31,000
propagules have been planted in nine sites. As the substrate is mainly coral gravel,
small iron rods were used to dig planting holes. These planting programmes were
participated by school children and youths (Fig. 29). In successful sites, survival
was 80% a year after planting and 50% three years after planting (Fig. 30). Besides
the poor nutrient contents of soils and the lack of freshwater supply, other factors
adversely affecting seedling growth are prolonged tidal submersion, strong wave
actions, barnacle infestation and seaweed entanglement.
4.3  Other coastal forests
Rationale for rehabilitation
Beaches and dunes
Strand vegetation is critical to the formation and stabilisation of beaches and dunes
(Craft, 2008; Cochard, 2008). Selection of suitable plant species is of paramount
importance when rehabilitating vegetation on bare dunes. Dune plants must be able
to survive sand blasting, sand burial, salt spray, saltwater flooding, heat, drought
and limited soil nutrient. Only a few plant species can tolerate these stresses. Most
post-tsunami attempts at planting tree species on beaches and dunes have failed
due to poor site and species selection, grazing by livestock and no maintenance
after planting (Wibisono & Suryadiputra, 2006).
It is therefore essential to adopt a prudent approach when rehabilitating beaches
and dunes. Planting programmes can be implemented in two stages. Initial planting
of primary sand-colonising herbaceous plants should be undertaken. They include
creeping herbs (e.g. Ipomoea pes-caprae and Canavalia rosea), sedges and grasses
(e.g.  Spinifex littoreus) for fore-dune stabilisation. Only when the dunes have an
adequate cover of ground vegetation, will the planting of woody tree species
commences. Progressively, natural regeneration will also play a role in the
development of the strand vegetation.
Coral islands
For many years, agro-forestry has become an integral component of the traditional
subsistence of people living on coral islands (Manner, 1993). Agro-forestry
practices, a sustainable land-use system, include wetland taro agriculture, mixed
tree gardening, backyard or kitchen gardens, and intermittent tree gardening. The
local communities know which varieties of food and native plants grew well or
poorly on their atolls, how to propagate them, and where they grew best (Stone et
al
., 2000). They recognise the problems of inadequate rainfall in some years and
poor soil fertility in many places when growing plants on atolls. They have addressed
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
38
these limitations by planting tolerant plants such as coconut and Pandanus species,
and by the intensive use of organic fertilizers from debris and household wastes.
Recognising the vulnerability of coral island to natural hazards such as tsunamis,
hurricanes and sea-level rise, efforts in rehabilitation of these islands should take
cognition of the limiting environmental factors and the wealth of local traditional
knowledge in growing plants on atoll soils. The use of indigenous tree species and
organic fertilizers is strongly encouraged. Small-scale planting trials to assess
growth performance are essential before embarking on large-scale rehabilitation
projects.
Choice of species
For the rehabilitation of other coastal forests, the choice of species and their
propagation methods described here are by no means exhaustive. They serve as a
guide and have been selected because some knowledge is available on their
silviculture. They are important forest trees and/or major food crops and they can
play a role in coastal protection. The species, and their life-forms, habitats and
propagation methods are listed in Table 7.
Table 7. List of coastal species, and their life-forms, habitats and
propagation methods
Choice of species
Life-form
Habitat
Propagation
Artocarpus altilis
Tree
Atoll
Seed/root sucker
Barringtonia asiatica
Tree
Dune/atoll
Seed
Calophyllum inophyllum
Tree
Dune/atoll
Seed
Canavalia rosea
Creeper
Beach/dune
Seed/cutting
Casuarina equisetifolia
Tree
Dune/atoll
Seed
Cocos nucifera
Palm
Dune/atoll
Seed
Hibiscus tiliaceus
Tree
Dune/atoll
Seed/cutting
Ipomoea pes-caprae
Creeper
Beach/dune
Seed/cutting
Melaleuca cajuputi
Tree
Dune
Seed
Pandanus odoratissimus
Herb
Dune/atoll
Seed/cutting
Scaevola taccada
Shrub
Dune/atoll
Seed/cutting
Spinifex littoreus
Grass
Dune
Seed/cutting
Terminalia cattapa
Tree
Dune/atoll
Seed
Thespesia populnea
Tree
Dune/atoll
Seed/cutting
Vitex trifolia
Shrub
Dune
Seed/cutting
background image
Guidelines for rehabilitation of coastal forests
39
References to information of these coastal species are mainly from Kitamura et al.
(1997); Stone et al. (2000), BPA (2004), Giesen et al. (2007), Selvam (2007), Craft
et al. (2008) and Hanley et al. (2008).
Artocarpus altilis
Artocarpus altilis (Moraceae) or breadfruit is a tree that grows to 30 m in height.
Leaves are alternately arranged, thick, leathery and deeply fissured with 5-11 pointed
lobes (Fig. 31). The upper leaf surface is dark glossy green with conspicuous yellow
veins. Being monoecious, male and female inflorescences are present on the same
tree. Male flowers are arranged densely on drooping, cylindrical or club-shaped
spike. Female inflorescences are upright and cylindrical with numerous embedded
flowers. Fruits are compound, ovoid to oblong in shape and vary from 10-35 cm in
length. The outer skin of the fruit is thin and patterned with irregular, 4-6 sided
faces, each of which has a minute, black pointed but flexible spine in the centre.
Fruits are green when young and yellowish-green or yellow when ripe. All parts of
the tree exude white latex. The species is an important staple food of the Pacific
Islands. In the Maldives, fruits are eaten raw, boiled, steamed or roasted.  Among
the food crops grown on coral islands, breadfruit is the least tolerant to soil salinity.
The species is normally propagated by transplanting root suckers. Trees grown from
root suckers will bear fruit in five years and will be productive for more than 50
years. Seeded varieties are propagated in the nursery and seedlings are out-planted
when they are 0.5 m tall.
Barringtonia asiatica
Barringtonia asiatica (Lecythidaceae) or sea putat is a small- to medium-sized tree
with heights ranging from 7-20 m. Leaves, spirally arranged in rosettes, are obovate,
thick and leathery. Flowers are large (10 cm in diameter) and scented with greenish-
white petals and showy white stamens with pink tips (Fig. 32). Fruits are large (10-
15 cm in diameter), cubic and have a broad square base that tapers towards the tip
which carries two persistent calyx lobes. Green when young and yellowish brown
when mature, the fruit has a tough fibrous husk and contains one large seed. The
species occurs from Madagascar to South and Southeast Asia, and from northern
Australia to the Pacific. The species is often planted as a shade tree along boulevards
and avenues along the sea, and grows well when planted inland. It is a littoral species
occurring on sandy and rocky shores, and occasionally in mangroves. It forms a
dense forest with overlapping crowns. It can be grown as windbreak, wave barrier
and shade trees. It is considered as one of the early colonisers of coral islands. It
can be propagated in the nursery with partial shade by embedding fruits with single
seeds in polythene bags with sandy soil. Seedlings with at least two pairs of leaves
and more than 30 cm in height are hardened before they are out-planted at 2-4 m
spacing.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
40
Calophyllum inophyllum
Calophyllum inophyllum (Guttiferae) or laurel wood is a spreading tree of 10-30 m
in height. It has a pale grey bark with shallow longitudinal grooves. Stems exude
sticky yellow or white latex when cut. Leaves are glossy, opposite, dark green above
and characterised by fine and dense parallel veins and a pale midrib. Flowers (2-3
cm in diameter) occurring in clusters are showy, white and fragrant with numerous
yellow stamens. Fruits are round, single-seeded berries (3-4 cm in diameter) that
hang from a long stalk (Fig. 33). Seeds are round and brownish-orange when mature.
The species occurs on sandy beaches and non-swampy coastal areas and is
distributed from East Africa through South and Southeast Asia to Polynesia. The
species is hardy and thrives well on sandy well-drained sites and is resistant to salt
spray. It is useful for shade, shelter and wind-breaks. Its fine timber is widely used
for boat building. It is quick to establish and is effective in stabilising coastal dunes.
Seeds may be sown directly or seedlings can be raised in the nursery before out-
planting. To improve the rate of germination, ripe fruits may be soaked in water
overnight. Nursery-raised seedlings should be hardened for 1-3 months before out-
planting at 2-4 m spacing.
Canavalia rosea
Canavalia rosea (Fabaceae) or sea bean is a perennial creeper of sandy beaches
and rocky shores. It is easily recognised by its round, trifoliate leaves and lilac
flowers (Fig. 34). Flowers are sweet scented and have a white streak in the middle
to attract pollination by bees. Fruits are 6-15 cm long, bean-like pods with 2-10
seeds. Flowers are used for flavouring, and young pods and seeds are edible after
boiling. The species is suitable as ground cover against soil erosion of sandy beaches
and dunes. Its long, creeping and branching stems with roots at the nodes spread
over the sand surface to form dense blankets. Being a legume, it can fix nitrogen
from the atmosphere. It often forms dense ground cover when growing in
combination with Spinifex littoreus and Ipomoea pes-caprae, and is a useful species
for mixed plantings on the frontal dune. It can be propagated from seeds which are
directly sown. Seeds with seed coat scarified germinate well in the nursery and
nursery seedlings can be out-planted. It can also be propagated from stem cuttings
with at least two rooted nodes for successful establishment.
Casuarina equisetifolia
Casuarina equisetifolia (Casuarinaceae) or she-oak is a fast-growing tree that
reaches 20-30 m in height. It resembles pine trees with their long-drooping needles
and small cones (Fig. 35). Trunks are straight, cylindrical, 5-8 m in height and
buttressed in older trees. The bark is smooth and greyish-brown when young, turning
to thick, fissured, flaky and dark brown when old. Whorls of tiny male flowers are
borne on branches which eventually drop off. Female flowers occurring as globular
background image
Guidelines for rehabilitation of coastal forests
41
clusters are borne on permanent branches. After pollination, the female flowers form
cones which are green when young and brown when mature. These woody cones
eventually shed small shiny brown winged seeds. The species is native to Australia,
Malaysia and the Pacific Islands. Although the species is a non-legume, it can fix
atmospheric nitrogen. This process improves the nitrogen content of the sandy soils
and enables other more nutrient-demanding species to establish. This salt-tolerant
and wind-resistant species is a valuable sand-binder. It grows in pure stands and
provides protection for the landward vegetation. It produces good firewood and
charcoal. It is propagated mainly by seeds which are collected from mature cones.
Seeds are sown in the nursery and out-planted when seedlings are about 0.3-0.5 m
tall. Seeds can be sown without any pre-treatment and seeds germinate within two
weeks. Seedlings can be planted singly or in groups of 3-4 seedlings at 3-5 m
spacing.
Cocos nucifera
Cocos nucifera (Arecaceae) or coconut palm is a tall tree with a stout, straight or
slightly curved trunk, rising from a swollen base surrounded by a mass of roots.
Trunk is greyish-brown, smooth with rings of leaf scars. Tall varieties may attain
heights of 20-30 m. Fronds are pinnate, up to 6 m long and 1.5-2.0 m wide with
200-250 leaflets arranged on either side of the rachis. Male and female flowers are
borne on the same inflorescence called a spadix that develops within a woody canoe-
shaped sheath and have 10-50 branchlets or spikelets. Male flowers are small, light
yellow, numerous and found at the tips of branchlets. Each spikelet has up to three
large female flowers at the base. Fruits are ovoid in shape and occur in bunches
(Fig. 36). Each fruit has a thick, fibrous husk surrounding a spherical nut with a
hard hairy shell. Three sunken holes or ‘eyes’ of soft tissue are present at one end
of the nut. Inside the shell is a thin, white, fleshy kernel. There are tall and dwarf
varieties of coconut with the former commonly cultivated around the world. The
species is well adapted to a wide variety of soils in the coastal areas. It grows well
in deep loamy and clayey soils with good drainage, and tolerates saline and infertile
soils but is intolerant to drought. It is a multiple-use palm which is considered as
one of the ten most useful trees in the world. It plays an important role in the
economy, and food security of many countries. It can only be propagated by seeds
collected from mature nuts with husk turning brown from green. Mature nuts are
stored in a shaded nursery and after 3-4 months, sprouted nuts are out-planted. The
hole is half filled with organic materials such as coconut husks. After placing the
sprouted nut, the hole is topped up with soil. Mature nuts can also be planted in
the nursery by burying two-third of their length in the soil to reduce desiccation.
Germination occurs 4-6 weeks after sowing and continues over an eight-week period.
Regular watering during this period is necessary. Nuts with fully developed
compound leaves are the best to be transferred to the field. Seedlings should be
out-planted not later than six months.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
42
Hibiscus tiliaceus
Hibiscus tiliaceus (Malvaceae) or sea hibiscus is a fast-growing tree that reaches
15 m tall. Leaves are leathery, hairy beneath, heart-shaped and have 1-3 nectary
glands at the base of the underside mid-rib. Flowers occurring singly are bell-shaped,
each with a maroon heart and stigma (Fig. 37). Flowers are yellow in the morning,
turning orange-red in the evening. The species is a coastal plant of the tropics and
sub-tropics. It is commonly found along the sandy shores of tropical Asia and
Australia, and is abundant in the Pacific Islands. It can withstand drought and
tolerate a wide variety of soils on coral islands. Soils range from coralline to swampy
soils. It is propagated from seeds and stem cuttings. Seeds, collected when the
capsules split, are scarified by lightly nicking their coats. Seedlings, 5-6 months
old and 25 cm in height, are suitable for out-planting. Stem cuttings, 2-3 m long
and collected from straight branches, are commonly used for propagation.
Ipomoea pes-caprae
Ipomoea pes-caprae (Convolvulaceae) or goat’s foot convolvulus is a perennial
creeping vine with milky sap. Roots are produced at the nodes. Leaves are alternate
and oval-shaped resembling the footprint of a goat. Flowers are attractive, pink or
purple and bell-shaped resembling those of the morning glory (Fig. 38). Fruits are
a flattened capsule with four black and densely hairy seeds. The species is common
along sandy beaches of Southeast Asia. It is a primary sand-stabilising species, being
one of the earliest plants to colonise the sand dunes including the seaward dune
slopes. Growing in association with Spinifex littoreus, this plant is a useful sand-
binder, thriving under conditions of sand blast and salt spray. It is propagated from
seeds or stem cuttings.
Melaleuca cajuputi
Melaleuca cajuputi (Myrtaceae) or paper bark tree grows to 25 m tall. The bark is
thick, whitish and flaky (Fig. 39). The crown is dense and green, with silvery new
leaf flush. Leaves are dull green and stiff with pointed tips. Flower spikes are white
or creamy, and fluffy resembling a bottlebrush. Capsules are grey-brown, broadly
cylindrical, thick-walled and contain numerous very fine seeds. The species is sand-
and salt-tolerant, and grows well in low-lying swamps, landward of frontal dunes.
Propagation is usually from seeds. Seedlings can be raised in the nursery and out-
planted when they are 30-40 cm tall.
Pandanus odoratissimus
Pandanus odoratissimus (Pandanaceae) or screw pine is an erect and coarsely
branched plant.  Growing to 15 m in height, the plant resembles a candle-stick
holder. Stems are usually pale grey-brown, hollow, ringed by leaf scars and produce
background image
Guidelines for rehabilitation of coastal forests
43
prop roots at the base. Leaves are sword-like and arranged spirally in three rows
(Fig. 40). At the basal underside of leaves are two clear pale green strips, one on
either side of the midrib.  The leaf apex is long and flagella-like. Under exposed
conditions, leaves hang downwards giving the plants a characteristic drooping
appearance. The species is dioecious with male and female flowers occurring in
separate plants. Male flowers are tiny, white, fragrant and last only for a day. Female
inflorescences are composed of free or joined carpels. Fruits, resembling pineapples,
are globular with tightly bunched, wedge-shaped fleshy drupes. They are green when
young and orange-red when ripe. Ripe fruits are eaten raw, drank as juice and used
in various food preparations. The species is commonly found growing in groves
along sandy and rocky shores. It an important food crop of the Pacific Islands and
the Maldives. It is propagated from seeds and branch cuttings. Seeds can be collected
from intact drupes. After soaking in water for several days, viable phalanges will
float. They can then be sown directly or propagated in a nursery. Seedlings, 4-12
months old, can be out-planted. Stem cuttings (20-40 cm) with some intact roots
can be planted immediately after collection to enable higher rate of establishment.
Scaevola taccada
Scaevola taccada (Goodeniaceae) or sea lettuce is a sprawling perennial shrub that
grows in dense stands to 3 m tall. Leaves are spoon-shaped, yellowish-green, thick
and spaced at 2 cm along the stem (Fig. 41). Stems are woody, slightly succulent
and crooked. Flowers are white, fragrant and petals are arranged in a 1.5 cm wide
fan. Fruits are a shiny, succulent and globular drupe, 2 cm in diameter, and white
or purple. The species is an effective sand-binder and is one of the early colonisers
of beaches. It grows in sites protected from strong winds and sand blasting. It can
be raised from seeds or stem cuttings. Both methods need shade and regular
watering. A dense stand can be established by planting seedlings or rooted cuttings
at 1 x 1 m spacing.
Spinifex littoreus
Spinifex littoreus (Poaceae) or sand spinifex is a stout perennial grass with strong
creeping runners which produce roots and rigid, spiny leaves at the nodes (Fig. 42).
The species is dioecious with male and female inflorescences borne on different
plants. Male inflorescences consist of stalked racemes while female inflorescences
consist of large, spiny and spherical head of stalkless racemes. The species is fairly
common along sandy shores and dunes from South and Southeast Asia to Taiwan
and southern Japan. It is a pioneer sand-stabilising species. The plant is salt-tolerant
and has the ability to grow in wind-blown sand. It grows well on frontal dunes and
is the dominant species colonising the seaward dune slopes. It is the main species
used in planting programmes for re-vegetating frontal dunes and is the most
successful sand-trapping plant colonising dunes along most of the coastline of
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
44
Queensland, Australia. It can be propagated from seedlings raised from seeds in
the nursery. Stem cuttings of 40-60 cm long can be directly planted in the field at
a depth of 20-30 cm.
Terminalia cattapa
Terminalia cattapa (Combretaceae) or Indian almond is a deciduous, moderate-sized
tree, 10-25 tall, with horizontal branching when young (Fig. 43). Leaves are spirally-
arranged and oval-obovate with 6-9 pairs of widely-spaced veins. Fruit pods are
angular and flattened. They are hard and green when young, turning red when
mature. Seeds contained in each pod are elliptic, tapering at both ends. Native to
Southeast Asia, the species is commonly found throughout the tropics and sub-
tropics. The species occurs on sandy and rocky shores and is commonly planted as
a shade tree. It grows on silty, loamy and clayey soils, and tolerates slightly saline
soils and moderate drought. It is an important timber tree in some countries. The
outer flesh and nut of the fruit are eaten fresh or dried. The species can be readily
propagated from seeds. Seeds, collected from mature fruits, should be sown within
4-6 weeks. No pre-treatment is needed. Seedlings grow rapidly in the initial stages.
Seedlings, four months of age or about 25 cm in height, can be used for out-planting.
Stem cuttings of 20-30 cm can be rooted in the nursery before planting.
Thespesia populnea
Thespesia populnea (Malvaceae) or tulip tree is a small, evergreen tree, 6-10 m in
height with short and often crooked trunk. The crown is round, broad, dense and
regular. The bark is brownish or greyish and fissured. Leaves are simple, alternate,
broadly ovate, pointed at the tip and slightly heart-shaped at the base. Leaves are
fleshy and shiny with palmate veins, turning yellow and red before falling. Flowers
are large, bell-shaped and axillary. Petals are f ive in number, broad, rounded,
overlapping and yellow with a maroon heart at the inside base of the corolla. Flower
colour changes from yellow to purplish as the day progress. Fruits are rounded but
flattened capsules. Mature capsules are brown to grey and exude a bright yellow
resin when cut. Seeds are brown and hairy. The species can be propagated from
seeds and stem cuttings. Seeds, collected from mature capsules by crushing, are
soaked in water overnight before sowing. Nursery-raised seedlings, 40-50 cm in
height, are hardened before out-planting. Stem cuttings are rooted in the nursery
before planting.
Vitex trifolia
Vitex trifolia (Lamiaceae) or coastal vitex is a low sprawling shrub with radiating
stems. The shrub produces adventitious roots and short, erect, flowering branches
at nodes along the stems. Leaves are greyish-green and flowers borne on erect
background image
Guidelines for rehabilitation of coastal forests
45
inflorescences are purplish-blue or lilac (Fig. 44). The species is widely distributed
throughout the tropics and sub-tropics. It can withstand moderate salt spray and
sand blasting. It grows well when planted behind the frontal dunes where it can
form dense stands. Being able to tolerate partial burial by wind-blown sand, it is a
useful secondary sand-stabilising species because of its sprawling growth habit and
sand-binding ability. It is propagated from nursery-raised seedlings or rooted
cuttings. Seeds germinate well in the nursery. Seedlings or rooted cuttings planted
in moist sand should produce a dense stand.
Site selection and preparation
In dune areas devoid of any vegetation, sand fences are often erected to trap sand
and to initiate dune building before planting can be undertaken (Craft et al., 2008).
Fences may be built using wooden pickets, bamboo, reeds or branches that deflect
and slow the wind. Guidelines for using fences include: 1) fences with 40-50%
porosity are most efficient in trapping sand; 2) install fences parallel to the shoreline;
and 3) a single row of fence is suitable for sites with lower wind speed and double
fences may be needed for sites with higher wind speed. As the dune builds,
continued sand trapping and dune growth are facilitated by installing additional
fences atop the original fences as they become buried. Planting can commence once
sand-binding pioneer species begin to colonise the site.
Seedlings should be planted in a manner to reproduce the natural vegetation zonation
(BPA, 2004). Guidance can be obtained by observing similar adjacent undisturbed
sites. Tree seedlings should not planted seaward of the fore-dune which can only
be colonised by the herbaceous pioneer plants. Casuarina equisetifolia can be
planted on the crest and landward slope of the fore-dune while other coastal species
can be planted in more sheltered areas landward of the fore-dune crest.
Post-tsunami planting of coastal species in Aceh included Terminalia cattapa,
Casuarina equisetifoliaCocos nucifera and Calophyllum inophyllum (Wibisono &
Suryadiputra, 2006; UNEP, 2007). Survival rate was only 20-50%. The major reason
for the low survival was poor selection of planting sites which included open, labile
and inundated sandy beaches and dunes. Open sandy beach is very difficult to
rehabilitate. Apart from being labile as the sand is easily moved by the wind, it is
highly saline and stores heat from the sun. It would seem obvious that such an area
is unsuitable for planting as nothing is growing on it. Nevertheless, planting has
been attempted on these sites and, as a result, most of the seedlings died. For coastal
species, inundation especially by saltwater is detrimental to plants. Some projects
have failed because coastal species were planted in places that were inundated.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
46
Propagation and planting
Seed collection, storage and treatment
Seed should be collected from mother trees growing on coastal dunes or atolls. It
is important to collect seeds from mature fruits (BPA, 2004). Collected fruits are
dried in the sun to release the seeds. Seeds of fleshy fruits are removed from the
pulp before drying. After drying, the seeds can be stored in airtight jars, kept under
cool, dry and dark conditions, or in a refrigerator. Seeds of dune plants with a hard
outer coat have to be treated by nicking with a sharp blade or by dipping in hot
water.
Raising seedlings in the nursery
Small seeds should be germinated in seed beds before seedlings are transplanted
into pots (BPA, 2004). Seeds can be sown evenly over the potting mixture before
covering with a thin layer of vermiculite. Larger seeds can be directly sown in
polythene bags. Several seeds are usually sown into each bag and later culled to
leave one plant. The sown seeds are kept moist by watering.
Seedling hardening
Nursery seedlings for dune or atoll planting must be hardened by exposing them to
full sun, wind and moderate moisture stress (BPA, 2004). Hardening usually takes
2-6 weeks. It is good practice to prune off some foliage of the seedlings during
out-planting to reduce excessive moisture loss.
Planting time and method
High temperature and low moisture of soils in planting sites are the major causes
of mortality of planted seedlings (BPA, 2004; Craft et al., 2008). Planting should
commence at the onset of the rainy season to avoid high soil temperatures and to
give the plants adequate soil moisture to colonise the site. There is much greater
flexibility in time of planting if the seedlings can be watered during the critical
establishment period.
At planting sites, the soil should be kept moist and the planting hole dug deep
enough to allow the root system to be completely buried (BPA, 2004). It is also
important to check that the root system of seedlings is healthy and is sufficiently
well-developed to hold the potting mixture firmly when the polythene bags are
removed. Seedlings are placed into planting holes and topped up with soil, which
is tamped down to complete the planting operation. Seedlings should be watered
before and after planting.
background image
Guidelines for rehabilitation of coastal forests
47
Stems cuttings of sand-binding primary species such as Spinifex littoreusIpomoea
pes-caprae  
and  Canavalia rosea can be collected for direct planting in the field.
Cuttings with several rooted nodes should be planted obliquely into moist soil so
that the growing end projects above the soil surface (BPA, 2004). Some form of
surface stabilisation such as brush matting may be required for sites exposed to
wind erosion. Because the stem cuttings are planted before their root system has
grown, some losses are common. Plant spacing ranges from 0.5-1.0 m depending
on the amount of planting material available.
Fertilizer application
The dune environment is harsh as sandy soils hold little water and are poor in
nutrients especially nitrogen (Craft et al., 2008). Dune vegetation responds
favourably to fertilizer which is applied 2-3 months after planting and in several
applications spread over the growing season.
For planting on atoll soils, the use of organic manure and/or household food waste
is recommended (Stone et al., 2000). Another source of fertilizer is compost from
leaves and coconut husks. These plant materials can be dumped into pits dug at
sites intended for planting.
Monitoring and tending
Poor survival of seedlings planted on dunes is often due to the moisture stress in
the f irst few weeks (BPA, 2004). This problem can be greatly reduced if the
seedlings are pruned and watered during this critical early stage. It is essential to
keep planted sites free of vehicular and foot traffic (Craft et al., 2008). In some
areas, fencing or caging of planted seedlings may be necessary to overcome the
problem of browsing by livestock. This would incur additional costs to the
rehabilitation effort.
For plants grown on atoll soils, water supply to the plants relies solely on the rain
which is scarce during periods of drought (Stone et al., 2000). On some atolls, rain
water runoff from roofs is stored and used for watering. Even waste water from
bathing and household washing is diverted to the plants. Sometimes, weeding and
mulching of plants are carried out to conserve soil moisture.
Case studies
Coastal rehabilitation project in the Maldives
The Republic of Maldives consists of some 1,190 low-lying coral islands, including
26 atolls (Jagtap & Untawale, 1999). Most of the islands (2 m asl) are enclosed by
coral reefs with shallow lagoons and deep channels. The soil is young, shallow and
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
48
composed mainly of coral debris and sandy loam with some surface humus. It is
alkaline with high calcium content and poor water retention capacity.
Common mangrove tree species found in the Maldives are Rhizophora mucronata,
Bruguiera cylindrica and Lumnitzera racemosa (Jagtap & Untawale, 1999; Selvam,
2007). Other coastal tree species include Terminalia cattapa,  Hibiscus tiliaceus,
Thespesia populnea,  Calophyllum inophyllum,  Pemphis acidula, Barringtonia
asiatica, Pongamia pinnata
 and Scaevola taccada.
With support from the local government, ISME has implemented a coastal
rehabilitation project in the Maldives since 2006. Funded by the Japan Fund for
Global Environment, the project is aimed at rehabilitating coastal forests in the wake
of the 2004 tsunami, severe coastal erosion and anticipated effects of sea- level rise.
The project is on-going with local communities participating in all activities of fruit
collection, seed processing, raising of seedlings in the nursery and planting in the
field (Baba & Yamagami, 2007). The project is located on Mulaku Atoll, and on
the islands of Boli Mulah, Dhiggaru and Maduvvari.
Coastal species planted were Terminalia cattapa,  Calophyllum inophyllum,
Barringtonia asiatica and Pometia pinnata. Nursery seedlings of these species were
raised successfully (Fig. 45). About 1,000 seven-month old seedlings of Terminalia
cattapa
 were planted on a beach of coral sand (Fig. 46). Although about 85% of
the seedlings were washed away by strong waves during high tide, the remaining
seedlings grew healthily after five months. Planting trials showed some promise as
the seedlings were neither watered nor fertilised. Future planting will include the
use of stakes to anchor the seedlings. Results of initial planting trials of the other
species showed that seedlings of Barringtonia asiatica had outstanding growth.
Post-tsunami rehabilitation in Aceh, Indonesia
Following the 2004 tsunami, government agencies and NGOs had implemented
planting projects on beaches and dunes. The total number and area planted were
403,400 seedlings and 29,000 ha, respectively (Wibisono & Suryadiputra, 2006;
UNEP, 2007). Of the total, 109,000 seedlings and 150 ha were planted through small
grants of the Green Coast Project coordinated by WIIP. Species planted were Cocos
nucifera
,  Terminalia cattapa,  Casuarina equisetifolia,  Azadirachta indica and
Calophyllum inophyllum.
Among the reasons for the failure of rehabilitation in some areas were planting on
labile and bare sandy beaches (Wibisono & Suryadiputra, 2006; UNEP, 2007). In
such sites, planted seedlings were exposed to winds, waves, saline soils and tidal
inundation. Other reasons included browsing by livestock, and the lack of monitoring
and evaluation. It was recommended that labile and bare sandy beaches should be
avoided, and planting should commence from the back to the front of the beach.
background image
Guidelines for rehabilitation of coastal forests
49
Natural regeneration in Lhok Nga, Aceh, Indonesia
Several years after the 2004 tsunami, coastal strand vegetation started to regenerate
naturally in Aceh (Wibisono & Suryadiputra, 2006). Mangroves performed poorly
with some localised regrowth of Nypa fruticans and  Avicennia species. Compared
to mangroves, the natural regeneration of other coastal species was much better.
Shrub forests consisting of a variety of plant species started to establish.
Lhok Nga in Aceh, famous for its scenic sandy beaches and Casuarina forests, was
impacted by the 2004 tsunami (Wibisono & Suryadiputra, 2006). Two years later,
most of the dune areas had very good natural regrowth of Casuarina equisetifolia
trees with dense ground cover of Ipomoea pes-caprae. A survey conducted by WIIP
in July 2006 showed densities of 3,800 saplings per hectare with heights ranging
from 0.5-3.5 m.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
50
H.T. Chan
Fig. 17. Propagules of Ceriops tagal (L)
Fig. 18. Gregarious stand of Nypa fruticans (R)
M. Kainuma
Fig. 15. Dense thicket of Acrostichum aureum ferns (L)
Fig. 16. Wasp visiting flowers of Bruguiera gymnorhiza (R)
H.T. Chan
K. Noguchi
Fig. 19. Inflorescences of Rhizophora apiculata (L)
Fig. 20. Rhizophora mucronata in flower (R)
H.T. Chan
H.T. Chan
background image
Guidelines for rehabilitation of coastal forests
51
Fig. 21. Leaves, inflorescences and flowers of Rhizophora stylosa
H.T. Chan
S. Baba
Fig. 22. Butterfly visiting flower of Sonneratia alba
S. Baba
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
52
Fig. 23. Tidal flat with deep mud is exposed to the vagaries of storms and
wave actions, deeply inundated, and devoid of any life forms
K.H. Tan
Fig. 24. Tidal flat with some early colonising individuals of pioneer species
H.T. Chan
background image
Guidelines for rehabilitation of coastal forests
53
Fig. 25. PVC tubes strewn on the mudflats due to strong wave actions (L)
Fig. 26. Unsuccessful planting of Rhizophora seedlings in bamboo tubes (R)
Fig. 27. Forests of Bruguiera gymnorhiza (a), Sonneratia alba (b) and Rhizophora
stylosa
 (c) in Kiribati (L)
Fig. 28. Line planting of Rhizophora stylosa propagules in groups of three in Kiribati
(R)
K.H. Tan
K.H. Tan
T. Suzuki
b
c
a
Y. Nakao
Fig. 29. School children participating in mangrove planting in Kiribati (L)
Fig. 30. One-year-old stand of Rhizophora stylosa planted in Kiribati (R)
Y. Nakao
Y. Nakao
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
54
Fig. 31. The breadfruit tree Artocarpus altilis (L)
Fig. 32. Flowers of the sea putat Barringtonia asiatica (R)
H.T. Chan
M. Kainuma
Fig. 33. Fruits of Calophyllum inophyllum (L)
Fig. 34. The sea bean Canavalia rosea (R)
K.H. Tan
H.T. Chan
Fig. 35. Mono-specific stand of Casuarina equisetifolia (L)
Fig. 36. The coconut palm Cocos nucifera (R)
    S. Havanond
H.T. Chan
background image
Guidelines for rehabilitation of coastal forests
55
Fig. 37. The sea hibiscus Hibiscus tiliaceus (L)
Fig. 38. The beach creeper Ipomoea pes-caprae (R)
H.T. Chan
H.T. Chan
Fig. 39. Flowers, trunk and bark of Melaleuca cajuputi (L)
Fig. 40. The screw pine Pandanus odoratissimus (R)
K.H. Tan
H.T. Chan
Fig. 41. The sea lettuce Scaevola taccada (L)
Fig. 42. The sand-stabilising grass Spinifex littoreus (R)
H.T. Chan
H.T. Chan
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
56
Fig. 43. The sea almond Terminalia cattapa
H.T. Chan
Fig. 44. The beach shrub Vitex trifolia
H.T. Chan
background image
Guidelines for rehabilitation of coastal forests
57
Fig. 46. Women planting seedlings (L) and healthy planted seedling (R) of
Terminalia cattapa
S. Yamagami
Fig. 45. Seedlings of Terminalia cattapa (L) and Calophyllum inophyllum
(R) in the nursery
S. Yamagami
background image
background image
References
59
Manual on Guidelines for Rehabilitation of Coastal Forests, H.T. Chan & S. Baba, 2009; p. 0–00
Akhter, M., Iqbal, M.Z. & Chowdhury, R.M., 2008. ASTER imagery of forest areas
of Sundarban damaged by cyclone Sidr. ISME/GLOMIS Electronic Journal 6:
1–2.
Angsupanich, S. & Havanond, S., 1996. Effects of barnacles on mangrove seedling
transplantation at Ban Don Bay, Southern Thailand. In: Proceedings of the
FORTROP ’96: Tropical Forestry in the 21
st
 Century, 25-28 November 1995,
Kasetsart University, Bangkok, Thailand, pp. 72–81.
Baba, S. & Yamagami, S., 2007. Progress of restoration of coastal forests for local
communities and coastal environment in small islands of Republic of Maldives.
Unpublished report of ISME submitted to the Japan Fund for Global
Environment (in Japanese), 23 pp.
Baba, S., Suzuki, T. & Nakao, Y., 2008. Progress of mangrove planting in Tarawa,
Republic of Kiribati. Unpublished report of ISME submitted to the Cosmo Oil
Eco Card Fund (in Japanese), 6 pp.
Balaji, V. & Gross, O., 2006. MANGREEN - Mangrove restoration and ecology in
India. Deepwave Report No. 4/06, 40 pp.
Barbier, E.B., 2006. Natural barriers to natural disasters: replanting mangroves after
the tsunami. Frontiers in Ecology and the Environment 4: 124–131.
Bird, E., 1985. Coastline Changes: A Global Review. John Wiley and Sons, 219
pp.
Bird, E., 1996. Beach Management. John Wiley and Sons, 281 pp.
Blasco, F., 2008. Impacts of recent natural hazards on mangrove ecosystems in the
Bay of Bengal. In: Chan, H.T. & Ong, J.E. (Eds.) Proceedings of the Meeting
and Workshop on Guidelines for the Rehabilitation of Mangroves and other
Coastal Forests damaged by Tsunamis and other Natural Hazards in the Asia-
Pacific Region. ISME and ITTO Mangrove Ecosystems Proceedings No. 5, pp.
97.
Blasco, F., Saenger, P. & Janodet, E., 1996. Mangroves as indicators of coastal
change. Catena 27: 167–178.
BPA, 1986. Report on cyclone Winifred. Beach Protection Authority, Environmental
Protection Agency of Queensland, 18 pp.
REFERENCES
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
60
BPA, 1999. Cyclones and their effects on beaches. Coastal Technical Series 3, Beach
Protection Authority, Environmental Protection Agency of Queensland, 4 pp.
BPA, 2004. Coastal Dune Management. Coastal Technical Series  1-5, Beach
Protection Authority, Environmental Protection Agency of Queensland.
Braatz, S., Fortuna, S., Broadhead, J. & Leslie, R. (Eds.), 2007. Proceedings of the
Regional Technical Workshop on Coastal Protection in the Aftermath of the
Indian Ocean Tsunami: What role for forests and trees?
 Khao Lak, Thailand,
28-31 August 2006.
Chan, H.T., Husin, N. & Chong, P.F., 1987. Is there a need to eradicate Acrostichum
speciosum prior to planting of Rhizophora mucronata in logged-over mangrove
forest areas? FRIM Occasional Papers 1/87, Forest Research Institute Malaysia.
Chan, H.T., 1988. Rehabilitation of logged-over mangrove areas using wildings of
Rhizophora apiculataJournal of Tropical Forest Science 1(2): 187–188.
Chan, H.T., Chong, P.F. & Ng. T.P., 1988. Silvicultural efforts in restoring mangroves
in degraded coastal areas in Peninsular Malaysia. In: Proceedings of the
International Symposium on Conservation and Management of Coral Reef and
Mangrove Ecosystems. Galaxea 7: 307–314.
Chan, H.T., 1996. Mangrove reforestation in Peninsular Malaysia: a case study of
Matang. In: Field, C. (Ed.) Restoration of Mangrove Ecosystems. International
Society for Mangrove Ecosystems, Okinawa, Japan, pp. 64–75.
Chan, H.T., Ong, J.E., Gong, W.K. & Sasekumar, A., 1993. The socio-economic,
ecological and environmental values of mangrove ecosystems in Malaysia and
their present state of conservation. In: Clough, B. (Ed.) The Economic and
Environmental Values of Mangrove Forests and their Present State of
Conservation in South-East Asia/Pacific Region. 
ISME, ITTO and JIAM
Mangrove Ecosystems Technical Reports, pp. 41–81.
Chandrasekar, N. & Ramesh, R., 2007. Tsunami damage to the south eastern coast
of India. In: Murty, T.S., Aswathanarayana, U. & Nirupama, N. (Eds.) The Indian
Ocean Tsunami. 
Taylor & Francis Group, LLC, pp. 351–363.
Check, E., 2005. Natural disasters: roots of recovery. Nature 438: 910–911.
Church, J.A., White, N.J., Hunter, J.R., 2006. Sea-level rise at tropical Pacific and
Indian Ocean islands. Global and Planetary Change 53: 155–168.
Clough, B. (Ed.), 1993. The Economic and Environmental Values of Mangrove
Forests and their Present State of Conservation in South-East Asia/Pacific
Region. ISME, ITTO and JIAM Mangrove Ecosystems Technical Reports Vol. 1,
202 pp.
background image
References
61
Coch, N.K., 1994. Geologic effects of hurricanes. Geomorphology 10: 37–63.
Cochard, R., 2008. The 2004 tsunami in Aceh and Southern Thailand: a review on
coastal ecosystems, wave hazards and vulnerability. Perspectives in Plant
Ecology, Evolution and Systematics 
10(1): 3–40.
Craft, C.B., Bertram, J. & Broome, S., 2008. Coastal zone restoration. In: Jorgensen,
S.E. & Fath, B. (Eds.) Encyclopedia of Ecology, 2008 Elsevier Ltd., pp. 637–
644.
Dahdouh-Guebas, F., Jayatissa, L.P., Di Nitto, D., Bosire, J.O., Lo Seen, D. &
Koedam, N., 2005. How effective were mangroves as a defence against the recent
tsunami? Current Biology 15(12): R443–R447.
Daniel, M. & Alongi, D.M., 2008. Mangrove forests: resilience, protection from
tsunamis, and responses to global climate change. Estuarine, Coastal and Shelf
Science
 76(1): 1–13.
Danielsen, F., Sorensen, M.K., Olwig, M.F., Selvam, V., Parish, F., Burgess, N.D.,
Hiraishi, T., Karunagaran, V.M., Rasmussen, M.S., Hansen, L.B., Quarto, A. &
Suryadiputra, N., 2005.  The Asian tsunami: a protective role for coastal
vegetation. Science 310: 643.
Duke, N.C., 2006. Australia’s Mangroves.  The authoritative guide to Australia’s
mangrove plants. University of Queensland, Brisbane, 200 pp.
EJF, 2006. Mangroves: nature’s defence against tsunamis - a report on the impact
of mangrove loss and shrimp farm development on coastal defences.
Environmental Justice Foundation, London, UK, 32 pp.
Ellison, J.C., 2008. Wetlands of the Pacific Island region. Wetlands Ecology and
Management, DOI 10.1007/s11273-008-9097-3.
EPU, 1986. National Coastal Erosion Study – Final Report. Report prepared for
the Economic Planning Unit of the Prime Minister’s Department Malaysia by
Stanley Consultants, Moffat & Nichol, and Jurutera Konsultant (SEA) Sdn. Bhd.
Erftemeijer, P.L.A. & Lewis III, R.R., 1999. Planting mangroves on intertidal
mudflats: habitat restoration or habitat conversion. Paper presented at the
ECOTONE-VIII Seminar on Enhancing Coastal Ecosystem Restoration for the
21
st
 Century, 23-28 May 1999, Ranong and Phuket, Thailand.
Field, C. (Ed.), 1996. Restoration of Mangrove Ecosystems. International Society
for Mangrove Ecosystems, Okinawa, Japan, 250 pp.
Field, C., 1998a. Rehabilitation of mangrove ecosystems: an overview. Marine
Pollution Bulletin 37(8-12): 383–392.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
62
Field, C., 1998b. Rationale and practices of mangrove afforestation. Marine and
Freshwater Research 49: 353–358.
Giesen, W., Wulfraat, S., Zieren, M. & Scholten, L., 2007. Mangrove Guidebook
for Southeast Asia. FAO and Wetland International, 769 pp.
Ghazali, N.H.M., 2006. New innovations and technologies in coastal rehabilitation.
In: Phang, S.M. et al. (Eds.) Innovations and Technologies in Oceanography
for Sustainable Development
. University of Malaya Maritime Research Centre,
pp. 141–156.
Gillespie, R.G., 2007. Oceanic islands: models of diversity. In: Levin, S.A. (Ed.)
Encyclopedia of Biodiversity, 2007 Elsevier Inc., pp 1-13.
GNF, 2007. Mangrove Rehabilitation Guidebook. Published in the framework of the
EU-ASIA PRO ECO II B Post Tsunami Project in Sri Lanka, Global Nature
Fund, 68 pp.
Hanley, J.R., 2007. Integrated land management to improve long-term benefits in
coastal areas of Asian tsunami-affected countries. In: Broadhead, J.S. & Leslie,
R.N. (Eds.) Proceedings of the Workshop on Area Planning and Management
Tsunami-affected Countries
, 27-29 September 2006, Bangkok, Thailand, pp.
253–286.
Hanley, R., Mamonto, D. & Broadhead, J., 2008. Coastal Forest Rehabilitation
Manual for Aceh Province and North Sumatra. Food and Agriculture
Organisation of the United Nations (FAO), Bangkok, 66 pp.
Harada, K. & Imamura, F., 2005. Effects of coastal forest on tsunami hazard
mitigation – a preliminary investigation. In: Satake, K. (Ed.) Tsunamis: Case
Studies and Recent Developments
 © 2005 Springer, pp. 279–292.
Harakunarak, A. & Aksornkoae, S., 2005. Life-saving belts: post-tsunami re-
assessment of mangrove ecosystem values and management in Thailand. Tropical
Coasts 
July 2005, pp. 48–55.
Hiraishi, T., 2008. Effectiveness of coastal forests in mitigating tsunami hazards.
In: Chan, H.T. & Ong, J.E. (Eds.) Proceedings of the Meeting and Workshop
on Guidelines for the Rehabilitation of Mangroves and other Coastal Forests
damaged by Tsunamis and other Natural Hazards in the Asia-Pacific Region.
ISME and ITTO Mangrove Ecosystems Proceedings No. 5, pp. 65–73.
IPCC, 1990. Strategies for Adaptation to Sea Level Rise. Coastal Zone Management
Subgroup, The Hague: Ministry of Transport and Public Work.
background image
References
63
Jagtap, T.G. & Untawale, A.G., 1999. Atoll mangroves and associated flora from
republic of Maldives, Indian Ocean. Mangrove Ecosystem Technical Reports,
ISME 
5: 17–25.
Kaly, U.L. & Jones, G.P., 1998. Mangrove restoration: a potential tool for
management in tropical developing countries. Ambio 27(8): 656–661.
Kathiresan, K. & Rajendran, N., 2005. Coastal mangrove forests mitigated tsunami.
Estuarine, Coastal and Shelf Science 65: 601–606.
King, D., 2008. Beach and shoreline. In: Lerner, B. & Lerner, K. (Eds.) Climate
Change: In Context. Detroit: Gale, 1: 119–120. 
Kitamura, S., Anwar, C., Chaniago, A. & Baba, S., 1997. Handbook of Mangroves
in Indonesia – Bali and Lombok. Ministry of Forestry Indonesia, JICA and
ISME, 119 pp.
Kogo, M. & Kogo, K., 2004. Towards sustainable use and management for mangrove
conservation in Vietnam. In: Vannucci, M. (Ed.) Mangrove Management and
Conservation
. United Nations University, pp. 233–248.
Manner, H.I., 1993. A review of traditional agroforestry in Micronesia. In:
Proceedings of the Workshop Methodologies and Applications for Pacific Island
Agroforestry
, 16-20 July 1990; Pohnpei, Federated States of Micronesia, pp. 32–
36.
Mazda, Y., Magi, M., Kogo, M. & Phan, N.H., 1997. Mangroves as coastal protection
from waves in Tong King Delta, Vietnam. Mangroves and Saltmarshes 1: 127–
135.
Mimura, N., 1999. Vulnerability of island countries in the South Pacific to sea level
rise and climate change. Climate Research 12: 137–143.
Mohd Ridza, A., 2006. Coastal forest rehabilitation and management in Malaysia.
Presented in the Workshop on Coastal Forest Rehabilitation and Management.
Bangkok, Thailand, 26 September 2006.
Moreno-Casasola, P., 2008. Ecosystems: Dunes. In: Jorgensen, S.E. & Fath, B. (Eds.)
Encyclopedia of Ecology, 2008 Elsevier Ltd., pp. 971–976.
Mueller-Dombois, A. & Fosberg, F.R., 1998. Vegetation of the Tropical Pacific
Islands. Springer-Verlag, 733 pp.
Naseer, A., 2007. Pre-and post-tsunami coastal planning and land-use policies and
issues in the Maldives. In: Broadhead, J.S. & Leslie, R.N. (Eds.) Proceedings
of the Workshop on Area Planning and Management Tsunami-affected Countries
,
27-29 September 2006, Bangkok, Thailand, pp. 147–164.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
64
Ong, J.E., 1995. The ecology of mangrove conservation and management.
Hydrobiologia 295: 343–351.
Ong, J.E., 2007. Pre- and post-tsunami coastal planning and land-use policies and
issues in Malaysia. In: Broadhead, J.S. & Leslie, R.N. (Eds.) Proceedings of
the Workshop on Area Planning and Management Tsunami Affected Countries
,
27-29 September 2006, Bangkok, Thailand, pp. 131–146.
Ong, J.E. & Tan, K.H., 2008. Mangrove and sea-level change. In: Chan, H.T. &
Ong, J.E. (Eds.) Proceedings of the Meeting and Workshop on Guidelines for
the Rehabilitation of Mangroves and other Coastal Forests damaged by Tsunamis
and other Natural Hazards in the Asia-Pacific Region. ISME and ITTO Mangrove
Ecosystems Proceedings No. 5
, pp. 89–96.
Osti, R., Tanaka, S. & Tokioka, T. (2008). The importance of mangrove forest in
tsunami disaster mitigation. Disasters 33: 203–213.
Paphavasit, N., Chotiyaputta, C. & Siriboon, S., 2007. Pre-and post-tsunami coastal
planning and land-use policies and issues in Thailand. In: Broadhead, J.S. &
Leslie, R.N. (Eds.) Proceedings of the Workshop on Area Planning and
Management Tsunami-affected Countries
, 27-29 September 2006, Bangkok,
Thailand, pp. 199–227.
Qureshi, M.T., 2008. Rehabilitation of mangroves in Sri Lanka and Thailand after
the 2004 Indian Ocean tsunami.  In: Chan, H.T. & Ong, J.E. (Eds.) Proceedings
of the Meeting and Workshop on Guidelines for the Rehabilitation of Mangroves
and other Coastal Forests damaged by Tsunamis and other Natural Hazards in
the Asia-Pacific Region. ISME and ITTO Mangrove Ecosystems Proceedings
No. 5
, pp. 15–20.
Robertson, A.I. & Duke, N.C., 1990. Recruitment, growth and residence time of
fishes in a tropical Australian mangrove system. Estuarine, Coastal and Shelf
Science
 31: 723–743.
Saenger, P. & Siddiqi, N.A., 1993. Land from the sea: the mangrove afforestation
program of Bangladesh. Ocean & Coastal Management 20: 23–39.
Samaranayake, R.A.D.B., 2007. Pre-and post-tsunami coastal planning and land-
use policies and issues in Sri Lanka. In: Broadhead, J.S. & Leslie, R.N. (Eds.)
Proceedings of the Workshop on Area Planning and Management Tsunami-
affected Countries
, 27-29 September 2006, Bangkok, Thailand, pp. 167–198.
Selvam, V., 2007. Trees and Shrubs of the Maldives. FAO Regional Office for Asia
and the Pacific, Bangkok, Thailand, RAP Publication 2007/12.
background image
References
65
Shofiyati, R., Dimyati, R.D., Kristijono, A. & Wahyunto, 2005. Tsunami effect in
Nanggroe Aceh Darussalam and North Sumatra Provinces, Indonesia. Asian
Journal of Geoinformatics
 5(2): 1–16.
Solomon, S.M. & Forbes, D.L., 1999. Coastal hazards and associated management
issues on South Pacific Islands. Ocean & Coastal Management 42: 523–554.
Spalding, M.D., Blasco, F. & Field, C.D. (Eds.), 1997. World Mangrove Atlas.
International Society for Mangrove Ecosystems, Okinawa, Japan, 178 pp.
Spalding, M., 2004. Mangroves. In: Burley, J. (Ed.) Encyclopedia of Forest Sciences,
2004, Elsevier Ltd., pp. 1704–1712.
Srinivas, H. & Nakagawa, Y., 2008. Environmental implications for disaster
preparedness: Lessons learnt from the Indian Ocean Tsunami. Journal of
Environmental Management 
89: 4–13.
Stone, E.L., Migvar, L. & Robison, W.L., 2000. Growing Plants on Atoll Soils.
Lawrence Livermore National Laboratory, University of California, UCRL-LR-
137517, 33 pp.
Sundaresan, J., 1993. Protection of tropical barrier beaches – a potential remedial
measure. Environmental Geology 22: 272–275.
Tan, K.H. & Ong, J.E., 2008. Coastal vegetation rehabilitation for the mitigation
of coastal hazards – The Malaysian experience. In: Chan, H.T. & Ong, J.E. (Eds.)
Proceedings of the Meeting and Workshop on Guidelines for the Rehabilitation
of Mangroves and other Coastal Forests damaged by Tsunamis and other Natural
Hazards in the Asia-Pacific Region. ISME and ITTO Mangrove Ecosystems
Proceedings No. 5
, pp. 57–63.
Thampanya, U., Vermaat, J.E., Sinsakul, S. & Panapitukkul, N., 2006. Coastal
erosion and mangrove progradation of southern Thailand. Estuarine, Coastal
and Shelf Science
 68: 75–85.
Than, M.M., 2008. Devastation of the 2008 cyclonic storms on mangrove and other
coastal ecosystems in Myanmar. In: Chan, H.T. & Ong, J.E. (Eds.) Proceedings
of the Meeting and Workshop on Guidelines for the Rehabilitation of Mangroves
and other Coastal Forests damaged by Tsunamis and other Natural Hazards in
the Asia-Pacific Region. ISME and ITTO Mangrove Ecosystems Proceedings
No. 5
, pp. 31–36.
Tomlinson, P.B., 1986. The Botany of Mangroves. Cambridge University Press, 413
pp.
background image
Manual on Guidelines for Rehabilitation of Coastal Forests Damaged by Natural Hazards
66
Triswanto, A., 2006. Coastal forest rehabilitation and management in Indonesia.
Presented in the Workshop on Coastal Forest Rehabilitation and Management.
Bangkok, Thailand, 26 September 2006.
UNEP, 2007. After the Tsunami Coastal Ecosystem Restoration: Lessons learnt.
United Nations Environment Program, 55 pp.
Walters, B.B., Ronnback, P., Kovacs, J.M., Crona, B., Hussain, S.A., Badola, R.,
Primavera, J.H., Barbier, E. & Dahdouh-Guebas F., 2008. Ethnobiology, socio-
economics and management of mangrove forests: a review. Aquatic Botany
89(2): 220–236.
Watson, J.G., 1928. Mangrove Forests of the Malay Peninsula. Malayan Forest
Records No. 6, 275 pp.
Wells, S.M., Ravilious, C. & Corcoran, E., 2006.  In the front line: shoreline
protection and other ecosystem services from mangroves and coral reefs. UNEP-
WCMC Biodiversity Series, No. 24
, 33 pp.
Wibisono, I.T.C. & Suryadiputra, I.N.N., 2006. Study of Lessons Learned from
Mangrove/Coastal Ecosystem Restoration Efforts in Aceh since the Tsunami.
Wetlands International – Indonesia Programme, Bogor, 83 pp.
Williams, M.J., Coles, R. & Primavera, J.H., 2007. A lesson from cyclone Larry:
an untold story of the success good coastal planning. Estuarine, Coastal and
Shelf Science
 71: 364–367.
Winterwerp, J.C., Borst, W.G. & De Vries, M.B., 2005. Pilot study on the erosion
and rehabilitation of a mangrove mud coast. Journal of Coastal Research 21:
223–230.
Wolanski, E., 2006. Protective functions of coastal forests and trees against natural
hazards. In: Braatz et al. (Eds.) Coastal protection in the aftermath of the Indian
Ocean tsunami: What role for forests and trees? 
28-31 August 2006, Khao Lak,
Thailand. Bangkok, FAO, pp. 5–32.
Wolanski, E. & Richmond, R.H., 2008. Estuary restoration. In: Jorgensen, S.E. &
Fath, B. (Eds.) Encyclopedia of Ecology, 2008 Elsevier Ltd.
Wong, P.P., 2003. Where have all the beaches gone? Coastal erosion in the tropics.
Singapore Journal of Tropical Geography 24(1): 111–132.
Woodroffe, C.D., 2008. Reef-island topography and the vulnerability of atolls to
sea-level rise. Global and Planetary Change 62: 77–96.
Yap, H.T., 2000. The case for restoration of tropical coastal ecosystems. Ocean &
Coastal Management 43: 841–851.