215

ORIGINAL PAPER

Development of Mangrove Stands in Southeast Asia:
With Special Reference to the West Coast of the Malay Peninsula
Ryuichi TABUCHI1*, Sarayudh BUNYAVEJCHEWIN2
and Pipat PATANAPONPAIBOON3
1

Forestry and Forest Products Research Institute (FFPRI)
1 Matsunosato, Tsukuba, Ibaraki 305-8687, Japan2
Department of National Park, Wildlife and Plant Conservation
61 Paholyotin Rd, Bangkok 10900, Thailand
3
Plant Ecology Research Unit, Faculty of Science, Chulalongkorn University
254 Phyathai Rd, Bangkok 10330, Thailand*e-mail: tabuchi@affrc.go.jp

Abstract
The authors analyzed the development of the size structure of some mangrove stands in Southeast Asiaand how it changed with growth, productivity and growth performance, as a source of diverse benefits tosustain the livelihood of local residents. The similarity of the development pattern of natural Rhizophoradominant stands to that of plantations suggested that the former were established as nearly evenly aged purestands. Stand productivity varied according to dominant species, such that the pioneer Avicennia standexamined in Ranong was smaller than the late successional Rhizophora stand, reflecting low tree density witha smaller basal area. Regional or environmental differences were also apparent, e.g., the annual biomass
growth rates in Kantang and some regions on the Thai Gulf side exceeded 15 Mg ha-1 yr-1 while those ofRanong and Merbok ranged between 10 and 15 Mg ha-1 yr-1, and stands in Bali showed smaller productivity,
around 5 Mg ha-1 yr-1. The lack of a large river system supplying fertility from upper tributaries was the most
likely factor affecting Bali’s low productivity. With biomass increase, forests release much plant mass as deadtrees, and this loss sometimes reaches the same level of net gain in mangroves. The average tree weight ofnatural Rhizophora-dominant stands at certain stand densities showed lower productivity than those of plantations and this tendency was common over wide regions of Thailand, Malaysia and Indonesia.
Key words: mangrove forests, productivity, Southeast Asia, stand development

1. Introduction
Mangroves offer great benefit to local residents(Watson, 1928; Yamada, 1997; FAO, 2007), sustaining
daily life in several ways. This valuable vegetation,
however, has been disappearing quickly in recent
decades due to overuse, deforestation and conversion toother land uses (FAO, 2007; Tabuchi, 2006). Such rapid
disappearance undoubtedly threatens the livelihoods ofpeople living among mangroves. The loss has been large
in Southeast Asia as the region most central to mangrovesin terms of both extent and plant diversity (Spalding et al.,2010) due to several forms of human impact. For example, Thailand lost more than half of its mangrove area
during the quarter century starting in the 1960s, andMalaysia lost 12% of its in the 1980s. Therefore, the wiseuse of remaining mangroves in a sustainable manner is aprime proposition and measures for managing the forests
have to be established based upon the traits of forest
Global Environmental Research
17/2013: 215-221
printed in Japandevelopment, e.g., growth patterns, productivity.
One of the characteristics of mangroves in Southeast
Asian countries is that they face human interference indestructive ways such as tree harvesting. This aspect
shall be taken into account as a major agent when we
consider or predict development of mangrove forests forconservation through sustainable resource use in particular, even though such forestry might be managed in aproper manner and quick recovery accomplished.
Another important characteristic of mangroves in thisregion is the presence of a large hinterland which supplies a flow of rich silt and nutrients from upper tributaries. The rapid sedimentation caused by the rich supply ofmatter from wide upper catchments (Woodroffe, 1992;
Smith, 1992) allows the forests to develop and change
quickly.
The objective of the present paper is to describe thetraits of some mangrove stands in Southeast Asia withspecial reference to their development, e.g., change of©2013 AIRIES216

R. TABUCHI et al.

structure and productivity. There have been many studies
on the productivity of mangrove forests; however, few
studies have successfully traced changes in the same
stands over time (Putz & Chan 1986; Ong et al., 1985,
1995; Ong, 1993; Poungparn et al., 2012) due to difficulties such as human impacts threatening the existence,
diversity and productivity of mangroves. Therefore, we
tried to show the dynamics of mangrove stands bymonitoring data over eight or twelve year periods inThailand and a two year period in Malaysia in the present
paper.

2. Study Sites and Methods
2.1 Sites
Monitoring data of some mangroves in Southeast
Asian countries were used for this study. The sites were
Suksamran, Ranong Province, and Kantang, Trang
Province and Samutsongkhram province in Thailand,
Merbok, Kedah State and Matang, Perak State in
Peninsula Malaysia, and Benoa Bay, Bali Province andGili Sulat, Lombok, NTB Province in Indonesia. Besides
these, a young experimental stand planted in a shrimp
pond in (vii) Samutsongkhram Province in Thailand wasstudied. Parameters characterizing the studied stands arelisted in Table 1.
Table 1 Parameters to characterize study stands.

2.2 Methods
a. Plot establishment
We established study plots to detect stand structure
and biomass, and to monitor the stand dynamics in someregions of Southeast Asia. The plots were square torectangular in shape, and varied from 100 to 10,000 m2 insize, reflecting the extent of stand and canopy tree sizes
and the study objectives as well.
b. Tree census
In each plot, all trees larger than 4 cm in trunk
diameter (D: cm) or larger than 1.3 m in height were
numbered, marked measured position to repeat measurement, and mapped for further repeated tracing; and thespecies were recorded along with the D measurement. In
the case of Rhizophora species, D was measured at 0.3 m
above the root collar while DBH (diameter at breast
height: 1.3 m above ground level) was measured as D for
non-Rhizophora species. Tree height (H: m) was measured for some sample trees to determine the D-H curvefor further H estimation.
c. Biomass estimation
Allometric equations for mangrove trees (Komiyama
et al., 1988) were applied to estimate partial tree weightby organ using D2H as the size parameter. In the case of
the young plantation in Samutsongkhram, another seriesof allometry with using H as the size parameter (Tabuchi
et al., 2007) was applied as follows for weight estimation,

Development of Mangrove Stands in Southeast Asia

since many trees were not enough large to allow DBH
measurement.
wS= 0.1063H2.2039
wB = 0.026H3.0848
wL= 0.0243H4.247
wRa = 0.1097H3.2044

(1),
(2),
(3),
(4)

Standing biomass was calculated as the sum of
individual tree weights over a certain land area (Mg ha-1).
The mass of dead trees during censuses was also estimated as the biomass loss.

3. Results and Discussion
3.1 Pattern of size structure changes
The structural changes of stands in plantations andnatural forest during twelve years are shown in Fig. 1.
(1)

217

The natural stand showed decreased tree density (ρ: treesha-1) from 1,001 to 598 together with the growth of
average D of Rhizophora trees. The predominant species
accounted for 97% of tree density in this stand, from 16.7
to 24.0 cm while the basal area of the stand grew from25.6 in 1987 to 29.7 m2 ha-1 (Tabuchi, 1990). A common
pattern was found in size structure and its change as
growth occurred when tracking the same stand over
several years, so that the single modal D frequency curve
gradually decreased its peak height, shifting mode
toward larger sizes and decreased tree density rapidly.
The resemblance of patterns of size structure
sequences between the plantations and the natural standsuggests that the natural stand grew in a similar manner
to an even- aged pure stand, like a plantation. The masspropagation by Rhizophora’s viviparous seeds transported by tides may allow the establishment of stands
within a short period, and its poor shade tolerance (Kitao
et al., 2003) possibly suppresses additional recruitment
once a stand is established. The fact that no seedlings infour stands at the Ranong site survived during themonitoring period over eight years in spite of continuous
seedling supply by tides may support the explanation
above.
3.2 Stand development
The relationship between standing biomass (Mg ha-1)
and age of some stands on the west coast of the Malay
Peninsula and in Bali are shown in Fig. 2. The
32-year-old stand is the oldest among them. In this figure,data are plotted from either plantations or natural standsof known age after regeneration. The curves drawn in the
figure suggest annual biomass growth rates of 5, 10,
15 and 20 Mg ha-1, respectively. Plantation data in(2)

Fig. 1 Change of D distribution pattern with stand developmentof mangroves in Kantang, Trang Prov., Thailand.
(1) Plantation, (2) Natural forest
Numbers 7, 19, 20 and 32 in (1) are stand age.

Fig. 2 Relationship between standing biomass and stand age.
Av: Avicennia pure or mixed stands. Ra: Rhizophora stands.
The lines shown with values in the figures, from upper tolower, are the level of 20, 15, 10 and 5 Mg ha-1 yr-1 in biomass
increment rate.

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R. TABUCHI et al.

Kongsanchai (1988) in mangrove stands around the Gulfof Thailand are plotted in the same figure.
There were clear differences in growth rate by regionand species. Rhizophora- dominant stands in Ranong andMerbok showed similar paths of biomass growth byage. Annual growth rates ranged between 10 and 15
Mg ha-1 yr-1, and plantations in Kantang showed muchhigher growth rates than naturally regenerated stands,
from ca. 15 to above 20 Mg ha-1 yr-1, reflecting highproductivity in habitat with rich matter supply fromupper tributaries. Plantations on the Gulf of Thailand side
showed similar growth rates to Kantang plantations.
Para-rubber cultivation in Thailand originated in
Kantang in the early 20th century and quickly spreadwidely (Institute of Southern Thai Study, 1986). Exploitation of natural forests as rubber plantations as well as
regeneration of plantations every 30 years or so caused
continuous soil erosion at the landscape level and possibly supplied fertile silt downstream.
There may be several possible agents affecting the
productivity of mangroves, e.g., inundation frequency,
salinity of water, climate and nutrient supply.
It may be worthwhile to evaluate the function of therich silt supply from intensively exploited hinterlands as
one of the possible agents bringing high productivity toplantations in Kantang and the well exploited Thai Gulf
side in comparison with Ranong, which was less exploited until the late 20th century.
A frequency distribution of annual biomass growth
rates, calculated as biomass divided by age, of mangrove
stands in Ranong as an example of the west coast of the
Malay Peninsula, where mangrove wood used to be harvested for charcoal making is shown in Fig. 3. Thesestands were supposed to have been regenerated after
clear felling 18 to 19 years ago. The mode was in theclass of between 10 and 12 Mg ha-1 yr-1 with an averageof 11.5 Mg ha-1 yr-1. The growth rate changed by age,as seen among pristine mangroves in Matang where
periodical harvesting continued in a sustainable manner,which showed a maximum standing biomass growth of

18 Mg ha-1 yr-1 in ten-year-old stands as a result ofmonitoring over seven years, declining to 13 at 15 yearsof age, and 12 at 25 years of stand age (Ong et al., 1985,
Ong, 1993, Ong et al., 1995). However, the officially
expected growth rate of the Matang mangrove forest in
Malaysia was 5.7 Mg ha-1 yr-1 (calculated from the final
harvest of 179 Mg ha-1 at 30 years of age). (Muda & Nik,
2003). The potential productivity of Thai mangroves may
satisfy the growth rate officially expected in Malaysiancharcoal making and make it possible to utilize them as asource of charcoal, although all mangrove harvesting
concessions have been cancelled in Thailand.
The growth rates of plantations in Bali, in contrast,
are low –less than 10 Mg ha-1 yr-1– due to low productivity of habitat. Low stand productivity can be observedin natural old growth stands in Bali, at ca. 12 m at a maximum at canopy heights in the vicinity of the study site.
That low productivity may reflects poor fertility owing to
the lack of a large river as a nutrient transporter pouring
into the bay.
Different dominant species also affect biomass andgrowth rate, so Avicennia alba-dominant stands inRanong show growth rates of around 5 Mg ha-1 yr-1, while
Rhizophora species-dominant stands of the same age
have growth rates larger than 10 Mg ha-1 yr-1 despite
being located nearby. This difference probably reflects adifference in basal area, with Avicennia stands in thisstudy having a smaller basal area, of 10.9 to 12.3 m2 ha-1,
than those of Rhizophora stands, of 22.0 to 24.5 m2 ha-1,
even though all the stands had closed canopies.
Differences in growth rates can be observed between
natural stands and plantations, with the growth rate of anatural stand in Trat Province, east Thailand being 7.88
to 10.06 Mg ha-1 yr-1 (Poungparn et al., 2012), which ismuch lower than those of plantations on the Gulf ofThailand coast (Kongsanchai, 1988) although differencesin age must be considered.
3.3 Increment and loss with growth
Figure 4 shows annual biomass changes, both98Frequency

7
6
5
4
3
2
1
0
2

4

6

8

10 12 14 16 18

Biomass increment (Mg ha-1 yr-1 )Fig. 3 Frequency distribution of annual standing biomass
increment (biomass divided by age) of mangroves (39stands) in Suksamran, Ranong, Thailand.

Fig. 4 Biomass changes with stand development in naturalforests, Kantang, Trang, Thailand.
Open circle ○: net annual increment.
Solid circle ●: annual loss by death.

Development of Mangrove Stands in Southeast Asia

increments and losses by death, during two sequential
censuses of a natural forest in Kantang from 1987 to 1999.
The values were converted into annual rates. Annual
increments as net growth amount were often affected by
the occasional death of large trees, as shown by large
fluctuations. Estimates over twelve years provided aclearer trend, with biomass increasing by ca. 133 Mg ha-1
during the twelve years from the initial 437 Mg ha-1 or
11.1 Mg ha-1 annually with a decline of tree density ρfrom 1,001 to 598 (trees ha-1). The biomass loss fromdeaths of standing trees mainly due to natural competition during the stand’s growth over the twelve years was
131.3 Mg ha-1 in total or 10.9 Mg ha-1 annually.
This stand was thus assumed to produce at least
22 Mg ha-1 of dry matter as gross value annually, releasing a large dead mass nearly equal to the net increment,
according to simple coupling of increment and loss. Thislarge gross value was found even when the othercomponents, e.g., leaf, branch and root litter produced,
uncounted during censuses, were ignored.
3.4 Biomass allocation
The partial biomass by organ, i.e., aboveground roots,
stems, branches and leaves with stand age are shown in
Fig. 5. Leaves and aboveground roots accounted for alarge portion of Rhizophora stands at the very beginning,as standing biomass was quite small – ca. 4 Mg ha-1.
Aboveground roots accounted for ca. 30% of total biomass in the very initial sage. Then as the stand developed,
above-ground roots decreased and then stayed at about
10% of the total. Stems rapidly increased their share with
development accounting for 70% to 80% of the total
amount. Branches stayed at ca. 10% from the beginning
but leaves decreased their share to a quite small amountas biomass increased. As the leaf biomass of pure andeven-aged closed stands increases quickly at the young
stage then reaches a constant level after passing throughits peak (Kira & Shidei, 1967), the leaf biomass of
Rhizophora stands showed its peak when the standing
biomass grew to ca. 200 Mg ha-1, then stabilized within arange between 10 to 18 Mg ha-1 at ten to 15 years of age.
The nearly steady proportion of above-ground roots after
1.00

stand establishment suggests Rhizophora stands need acertain amount of stilt roots to sustain their growing biomass on the soft muddy substratum.
3.5 Growth and density
We plotted the relationship between average tree
weight and tree density of stands in Fig. 6 to show thepotential pattern of size structural change with standdevelopment, then examined the extensibility of fulldensity curves of Rhizophora stands in Thailand, which
Kongsanchai (1988) proposed, applying the 3/2 powerlaw of self-thinning (Yoda et al., 1963). We compared themangrove data of this study taken over a wider region,
including Thailand, Peninsular Malaysia and Indonesia
to Kongsanchai’s (1988) data.
The relationship we obtained is based on the universal
phenomenon that plant populations decrease in densitywith biomass accumulation (Shidei, 1956; Kira 1957a, b,c; Tadaki, 1964; Ando, 1968; Harper, 1977), and aredescribed by a formula between the average plant weight(w) and plant density (ρ) of a species in pure, closed
stands as,
w = K･ρ-3/2(5)

where K is a coefficient that varies by species.
This relationship drawn on a log-log diagram shows
the potential of the species so that w and ρ of any stand

Leaf

0.90

Branch0.80

Allocation by organ

219

0.70
0.60

Stem

0.50
0.40
0.30
0.20
0.10

Aboveground root

0.00
0.0

100.0

200.0

300.0

400.0

500.0

600.0

Standing biomass (Mg ha‐1 )Fig. 5 Allocation patterns of standing biomass by organ (stem,
aboveground roots, branches and leaves) along withstand development.

Fig. 6 Full density curves for natural forests (broken line) andfor plantations (solid line).
○: natural stands and ●: plantations of this study; ᇞ: natural stands
and ▲: plantations after Kongsanchai (1988)

220

R. TABUCHI et al.

can be plotted beneath this curve. The value K is, therefore, useful for indicating the characteristics of mangrove
stands too. Kongsanchai (1988) has examined the fulldensity curve of the 3/2 power law for mangroves toanalyze the population dynamics with stand developmentusing data from plantations on the Gulf of Thailand sideand natural forests on the west coast of the Thai part of
the Malay Peninsula in order to utilize forest management such as density control of plantations. He presented
two curves with a common power index of -1.567 or
inclination in a log-log diagram, but different inceptionsof 7.5533 and 2.0389 for plantations and natural forests,
respectively. His study examined the relationship between tree volume (v) and ρ. However, we regard v as
weight, w, because of Rhizophora’s high specific gravity
of wood, at around 1.0 (Ogata et al., 2008).
Almost of all the stands were plotted beneath the two
curves for natural stands and plantations, respectively.
The results suggested that plantations were potentiallyable to hold a larger biomass than natural forest at certain
stand densities due to smaller size variation in the standthan occurred in natural stands, which included manysmall trees. It was obvious that Kongsanchai’ (1988) fulldensity curve could be extended enough to summarize
Rhizophora’s density-weight relationship with standdevelopment over a wide area of Southeast Asia.

Acknowledgements
We extend our sincere appreciation to all collaborators who supported field work and encouraged us withvaluable discussions. Over many years, our studies havebeen supported by several academic funds, i.e., Global
Environmental Research Account for National Institutesof the Ministry of the Environment, Government ofJapan; the Research and Training in Re-Afforestation
Project, Royal Forest Department, Thailand; and theJapan International Cooperative Agency, Japan International Research Center for Agricultural Science’s Comprehensive Project on “Productivity and Sustainable
Utilization of Brackish Water Mangrove Ecosystems II.”
References
Ando, T. (1968) Ecological studies on the stand density control ineven-aged pure stand. Bulletin of Governmental Forestry Station,
210:153. (in Japanese with English summary)
FAO (2007) The World’s Mangroves 1980-2005. FAO forestry
paper 153. FAO, Rome.
Harper, J.L. (1977) Population Biology of Plants. Academic Press,
London.
Institute of Southern Thai Study (1986) Para rubber. In: Dictionaryof Southern Thai Culture, (Tentative translation from
Saranukrom Watanatam Paaktai, 7, 2792-2768, Amarin Press,
Bangkok).
Kira, T. (1957a) Density, competition and production (1). Miyama,
Osaka Governmental. Forestry Office, Osaka, 8: 13-24.
Kira, T. (1957b) Density, competition and production (2). Miyama,
Osaka Governmental. Forestry Office, Osaka, 9: 9-18.
Kira, T. (1957c) Density, competition and production (3). Ditto,
11･12: 34-45. (in Japanese)

Kira, T. and Shidei T. (1967) Primary production and turnover oforganic matter in different forest ecosystems of the western
Pacific. Japanese Journal of Ecology, 17:70-87.
Kitao, M., H. Utsugi, S. Kuramoto, R. Tabuchi, K. Fujimoto and S.
Lihpai (2003) Light-dependent photosynthetic characteristics
indicated by chlorophyll fluorescence in five mangrove species
native to Pohnpei Island, Micronesia. Physiologia Plantarum,
117, 3: 376-382.
Komiyama, A., H. Moriya, S. Prawiroatmodjo, T. Toma and K.
Ogino (1988) Forest primary productivity. In: K. Ogino and M.
Chihara, eds., Biological System of Mangroves, A Report of East
Indonesian Mangrove Expedition 1986, Ehime University,
Matsuyama, Japan.
Kongsanchai, J. (1988) Forest Ecological Study of Mangrove
Silviculture. PhD dissertation, Kyoto University, Japan.
Muda, Azahar and Nik Mohd Shah (2003) A Working Plan for the
Matang Mangrove Forest Reserve, Perak (Fifth Revision). State
Forestry Department of Perak Darul Ridzuan, 3.
Ogata, K., T. Fujii, H. Abe and P. Baas (2008) Identification of theTimbers of Southeast Asia and Western Pacific. Forestry andForest Products Research Institute, Kaiseisha Press. Otsu, Japan.
Ong. J.E., W.K. Gong and C.H. Wong (1985) Seven year of
productivity studies in a Malaysian managed mangrove forest.
Then what? In: J.D.S. Davie and C.D. Woodroffe, eds., Coasts
and Tidal Wetlands of the Australian Monsoon Region, K.N.
Bardsley, Australia National University, 213-223.
Ong, J.E. (1993) Mangroves–a carbon source and sink. Chemosphere, Pergamon Press, 27: 1097-1107.
Ong, J.E., W.K., Gong and B.F. Clough (1995) Structure andproductivity of a 20-year-old stand of Rhizophora apiculata Bl.
Mangrove forest. Journal of Biogeography, 22: 417-424.
Poungparn, S., A. Komiyama, T. Sangteian, C. Maknuai, P.
Pataaponpaiboon and V. Suchewaboripont (2012) High primary
productivity under submerged soil raises the net ecosystemproductivity of a secondary mangrove forest in eastern Thailand.
Journal of Tropical Ecology, 28: 303-306.
Putz, F.E. and H.T. Chan (1986) Tree growth, dynamics, andproductivity in a mature mangrove forest in Malaysia. Forest
Ecology and Management, 17: 211-230.
Shidei, T. (1956) Problem of Stand Density. Nippon Ringyo Gijuty
Kyokai, Tokyo. (in Japanese)
Smith, T.J. (1992) Forest structure. In: A.I. Robertson and D.M.
Alongi, eds., Tropical Mangrove Ecosystems, American
Geophysical Union, Washington, D.C., 101-136.
Spalding, M., M. Kainuma and L. Collins (2010) World Atlas ofMangroves. Earthscan, London.
Tabuchi, R. and T. Visaratana (1990) Stand structure of young
mangrove forest at KANTANG, Southern Thailand. Transactionof Japanese Forestry Society, 101: 19-2. (in Japanese)
Tabuchi, R. (2006) Rehabilitation of mangroves in south-east Asia.
In: K.G. Saxena, L. Liang, Y. Kono and S. Miyata, eds.,
Small-scale Livelihoods and Natural Resource Management in
Marginal Areas of Monsoon Asia, Bishen Singh Mahendra Pal
Singh, Dehra Dun, India, 81-86.
Tabuchi, R., H. Tanouchi, D. Hoshino, S. Saito, Y. Fujioka, Y.
Hanamura, C. Aryutthaka, S. Nimsanthicharoen, P. E. Chee andT. Shimoda (2007) Contribution of mangroves to the sustainableproduction of marine animals. In: Nakamura N., ed., Sustainable
Production Systems of Aquatic Animals in Brackish Mangrove
Areas (2005), JIRCAS Working Report 56, Japan International
Research Center for Agricultural Science, Tsukuba, Japan,
59-64.
Tadaki, Y. (1964) Effect of thinning on stem volume yield studied
with competition – density effect. On the case of Pinus
densiflora forest. Bulletin of Governmental Forestry Station,
Tokyo, 166: 1-22.
Watson J. G. (1928) Mangrove forests of Malay Peninsula,
Malayan Forest Records 6, Forest Department, Federated Malay
States, Kuala Lumpur.

Development of Mangrove Stands in Southeast Asia
Woodroffe, C. (1992) Mangrove sediments and geomorphology.
In: A.I. Robertson and D.M. Alongi, eds., Tropical Mangrove
Ecosystems, American Geophysical Union, Washington, D.C.,
7-41.
Yamada, I. (1997) Tropical Rain Forests of Southeast Asia – A
Forest Ecologist’s View-. Center for Southeast Asian studies,
Kyoto University, English-language series, 26, University of
Hawaii Press, Honolulu.
Yoda. K., T. Kira, H. Ogawa and K. Hozumi (1963) Self-thinningin overcrowded pure stands under cultivated and natural conditions. Journal of Biology, Osaka City University, 14: 107-129.

221

Ryuichi TABUCHI
Ryuichi TABUCHI is a senior researcher at theForestry and Forest Products Research InstituteJapan. Since studying in Thailand under a fellowship of the Thai Government when he was a
graduate school student, he has continued to be
attracted by the topic of forest ecosystems in thetropics and has been involved in several forest
ecological studies in Southeast Asia and Pacific islands. His major interest
is in swamp forests, particularly mangroves, which involve human activity
as an important component and sustain the livelihood of local residents.

Sarayudh BUNYAVEJCHEWIN
Sarayudh BUNYAVEJCHEWIN is a Special Expert
at the Department of National Parks, Wildlife
and Plant conservation, Thailand. He got his
Ph.D. from Osaka City University, Japan. Since
beginning his career as a forest scientist at theRoyal Forest Department, he has been involved
with and led a lot of botanical and ecologicalstudies over many years, and is well known as one of the leading scientists
in forest ecology in Thailand. His study fields range from rich naturalforests to plantations. Prior to his current position he was chief of the
Kantang Eological Research Station for more than a decade, where he led
mangrove studies.

Pipat PATANAPONPAIBOON
Pipat PATANAPONPAIBOON is a Professor at theFaculty of Science, Chulalongkorn University,
Thailand. He began his academic career as aplant taxonomist and extended his study fields toinclude ecological studies receiving his Ph.D.
from Ehime University, Japan, in ecophysiological studies of mangroves. He lends the
Plant Ecology Research Unit and is driving several ecological research
projects covering a wide area including mangrove environments in many
coastal regions and extending as far as northern mountain environments.

(Received 13 December 2012, Accepted 20 May 2013)