Lembar Ke 9 The Role of mangrove on mud substrate
PROCEEI}INGIS OF WNAL
CONFENENCE ON
NEW PERSPESrIVES OF TBOPICAL FONEST MN
FOB BETTER NONBST FT'NSTTONS ANI' M.{I,NAGEMENT
17*-19* October 2011
Faculty of Forestry Universitas Gadjah Mada
Yogyakarta, Indonesia
Editors:
Eko Bhakti Hardiyanto
Svein Solberg
Mitsuru Osaki
PROCEEDING OF INTERNATIONAL CONFERENCE ON
NEW PERSPECTIVES
OF TROPICAL F'OREST REHABILITATION FOR BETTER
FOREST FUNCTIONS
AND MANAGEMENT
Editors:
Eko Bhakti Hardiyanto
Universitas Gadjah Mada, yogyakarta, Indonesia
Svein Solberg
Norwegian Forest and Landscape Institute, Norway
Research Faculty
"rAHJi1il:,oJffi",u"
Faculty of Forestry
Universitas Gadjah Mada
2012
university, Japan
Proceeding of International Conference on New Perspectives of Tfopical Forest
Rehabilitation for Better Forest Functions and Management
t7th-tgth ocToBER
2011
Yogyakarta, Indonesia 2011
by Faculty of Forestry Universitas Gadjah Mada
Citation:
Hardiyanto , E.B, Solberg, S., Osaki, M. (eds.) 2012. Proceeding of International
Conference on New Perspectives of Tropical Forest Rehabilitation for Better Forest
Functions and Management, 17 th-lgth October 20 I l, Yogyakarta, Indonesia. Faculty of
Forestry Universitas Gadjah Mada.
Published by Faculty of Forestry, Universitas Gadjah Mada
Jl. Agro No l, Bulaksumur, Yogyakarta 55281
ISBN z 979-9924-66-9
Cover Design: GLM Printika
Printed in Indonesia
PREFACE
The degraded forest lands are of concern of rehabilitation programs, as they are usually the
centre areas of poverty, natural disaster (flood-drought) and climate change (hot spot of carbon
emission). However, fundamental understanding is prerequisite to provide a more generic principle
and technology to support successful rehabilitation in different forest types. Likewise, a more
contextual approach for the rehabilitation should also adopt the strategy to strengthen the sustainable
livelihood and more efficient timber processing at the local community level in order to reduce
deforestation and degradation. The international conference on New Perspective of Tropical Forest
Rehabilitation is proposed to strengthen an integrated approach in forest rehabilitation therefore
provide ecological landscape safety-net which are economically-viable and therefore could be selfsustaining in reducing pressure to forests.
The conference invites four international speakers in the field of tropical silviculture, tree
physiology and ecology from Indonesia, Australia, Norway, Japan and other international partners.
Participants are academicians, researchers, practitioners and students. Through the conference,
the participants will strengthen an integrated approach and establish new paradigm in managing
tropical forest rehabilitation for reducing deforestation and forest degradation.
The objectives of the conference are: 1). identitring the gap and updating the current status of
the methods and techniques on tropical forest rehabilitations, and 2). strengthening collaborations
with domestic and international parhrers in developing rehabilitation strategy for sustainable and
productive tropical forests.
The participants of the conference were from Japan, Malaysia, Hawaii USA, Norway and
Indonesia.
I would like to acknowledge all the authors for the paper contributed in this proceeding,
the
comment and review of the editors toward the publishment of this proceeding are also greatly
appreciated.
ThankYou
Organizing Committee
Proceeding of lntemational Conference on New Perspectives of Tropical Forest Rehabilitation for Better Forest Fuctions and Management
I
v
CONTENTS
Page
PREFACE
v
PHOTO SESSION
CONTENTS
vi
vii
ROBUST MONITORING TECHNIQUES
ON LARGE SCALE CARBON
DYNAMICS FOR REDD+ IN TROPICAL PEAILAND-FOREST
Mitsuru Osaki, Kazuyo Hirose, Noriyuki Kobayashi, Muhammad Evri and
Farhan Helmy (Keynote Speaker)
l-1s
FOREST BIOMASS MONITORING
Svein Solberg, Rasmus Astrup, Johannes Breidenbach and
Arnt Kristian
t6-22
Gjertsen (Keynote Speaker)
FORESTRY FOR PEOPLE: WE NEED A REFRESHED APPROACH
Sadanandan Nambiar (Keynote Speaker)
23-24
THE SOCIAL IMPACT OF REHABILITATION PROJECTS IN PROTECTED
AREAS: CASE STUDY AT SEBANGAU NATIONAL PARK CENTRAL
KALIMANTAN
Tri Wira Yuwati and Petrus Gunarso
2s-29
FOREST RESOURCE MANAGEMENT ON DAYAK KANAYATN COMMUNITY
Emi
Roslinda
30_33
ILENGI AGROFORESTRY SYSTEMS : A STUDY OF CONSERVATION AND
UTILIZNIION OF TREE SPECIES (Case Studies in South Dulamayo Village,
District Telaga, Gorontalo Province)
A. S. Hiola, N. Wijayanto, S.Adiwibowo, M. CoIIins
34-31
ON DIPTEROCARP TREE PLANTING IN
SMALLHOLDER RUBBER PLANTATION
Hesti L.Tata and Meine van Noordwijk
38-41
COMMUNITY-CENTERED FORE ST REHAB ILITA TION IN INDONESIA : PAST
EXPERIENCES AND FUTURE DIRECTION
Didik Suharjito
42-46
FARMERS PARTICIPATION
Proceeding of Intunaional Conference on New Perspectives of Tropical Forest Rehabilitation for Beuer Forest Functions and Maragemort
I
vii
rTHE ROLE OF MANGROVE ON MUD SUBSTRATE ACCUMULATION IN
REHABILITATED AREA ON THE NORTH COAST OF BREBES CENTRAL
JAVA
Erny
Poedjirahajoe
221-223
THE ROLE OF MANGROVE REHABILITATION ACTION ON CARBON
RESOURCE MANAGEMENT: A CASE STUDY FROM A MANGROVE
REHABILITATION SITE AT PEMALANG, THE NORTH COASTAL OF
CENTRAL JAVA, INDONESIA
Ni Putu Diana
Mahayani
224-228
LIST OF PARTICIPANT
t
xii
I froceoaAg of Intenmiunl Curferurce
on New Perpeciives ofTiopical Forest Rehabiliblion for Betrer Forest Functions and Maragement
THE ROLE OF MANGROVE ON MUD SUBSTRATE ACCUMULATION
IN REHABILITATED AREA ON THE NORTH COAST OF BREBES
CENTRAL JAVA
Erny poedjirahajoel
1)
F aculty of Forestry, Universitas Gadjah Mada, Y ogyakarta
(erjjr@yahcom)
ABSTRACT
The role of mangrove as land stabilizer can adds or increases of the land area towards the sea.
The result of mud accumulation which is called tanah timbul is useful for mangrove growth. This
research was a case study established in Brebes district, which is part of North Coast of
Cenkal
java. The objective was to determine the role and the ability of *urrgrove roots (Rhizophora
mucronata) in mud substrate accumulation on mangrove rehabilitation *"ur. The resear.h *u,
conducted by measuring root density, root width, tree density, tree height and tree diameter,
and
mud thickness in 5 m x 5 m square plots, with 15 replication. The plots were established in
different planting year,i.e., 1999, 2003 and 2006. Analysis of data was ionducted using variance
design and correlation regression on relationship between R.mucronata densities with mud
thickness. The result showed that the root srtructure and density of R.mucronata were able
to
accumulate mud subtrate, with an average of 28.8, 62.7 cm and, 107.1 cm on planting year
of
2006, 2003 and 1999 respectively. Base on the result, it can be concluded that the area of
manStrove rehabilitation area in Brebes's coast planted with R.mucronata has improved
the plant
density, which will eventually accumulate the mud substrate on every mangrove rehabilitation
area and expands land towards the sea.
INTRODUCTION
Mangrove is a swamp ecosystem which the vegetation live requires ahabitatcontaining salinity,
small wave, influenced by tides, the existence of mud and mud thickness. Those are the main
requirements which have to be fulfilled to ensure the existence of mangrove (poedjirahajoe,
1998). Mangrove's mud plays a great role on supplying micro elements to its ecosystem.
The
supply of micro elements by the mud is not stable because some of the micro elements are lost
by
river stream and ended in the sea. However, the most available micro elements which are used to
supply the energy are supplied by phytoplankton, those elements are resulted from its
photosynthesis. Therefore, in directly, the growth of mangrove could be detected through
the
density of phytoplankton. The productivity of mangrove is highly influenced by the produltivity
of phytoplankton (Poedjirah ajoe, 2006).
The tsunami has caused the loss of many lives. One of the causes is the loss of tidal forest
conservation area functions because of forest degradation for quite a long time. Currently,
some
efforts to restore the functions of mangrove in Indonesiaarebeing deviloped. One of them is
through rehabilitation of mangrove forest. Mangrove rehabilitation is intended to restore the
original functions of its ecosystem. Mangrove functions as a conservation, physically it is
capable in preventing the abration and intrusion of sea water and also stabilizes the soil. Through
its complicated root skucfure, one of mangrove species, e.i. Rhizhophora mucronata, which is
used as the main vegetation on rehabilitation program, has been able to kept the supply of both
organic and inorganic substances from the sea and the rivers (Macnae, 1968). 1.he supplies are in
the form of soft mud which are retained by mangrove roots and then accumulated, tirus forming
thick mud which becomes the characteristics of mangrove habitat.
Proceeding of Intemational Conference on New Perspectives ofTropical Forest Rehabilitation for Better Forest
Fr.mctions and Mur{Ierneltt
l22l
One of the species which is used as the main vegetation in mangrove forest rehabilitation is
Rhizophora, spp. This species has been determined by the Indonesian Forestry Department as
one of the species for mangrove forest rehabilitation vegetation. The decision was based on
Rhizophora's root structure which has aerial roots, complicated and able to endure sea waves and
to accumulate mud from the rivers and the sea (Sukardjo, 1993). Mangrove roots structure can
expand land formation towards the sea. As a result, the land becomes wider and more stable. The
great role of mangrove root strucfure towards its ecosystem is the perfect mangrove conservation
function for the land (Macintosh and Ashton,2002). Therefore, such ecological role should be
maintained as the support system for life on the land.
The accumulation of mud as mangrove substrate is very potential in forming new land so that
mangrove habitat is kept expanding. Besides that, mud also contains various organic substances
and micro elements thus mud thickness represents the availability of micro elements in mangrove
habitat (Kathiresan and Bingham. 2001). Such condition has to be kept developed so that
mangrove function as a conservation area can be quickly achieved. The objectives of this
research were to: (l)Find out the signif,rcance of mud thickness in mangrove rehabilitation area in
planting year of 1999,2003 and 2006. (2) Find out the influence of mangrove density on mud
thickness.
METHOD
This research was conducted in mangrove rehabilitation area on the North Coast of Brebes,
Central Java. The total area of mangrove rehabilitation is 10 ha consisting of various planting
years. This research was established only on planting year of 1999,2003 and2006 because it has
a fast growth. Tools which used in this research were ro11 meter, scaling pole, salt test, pH tester
and soil thermometer. The research was conducted through determining the width of sample area,
which in approximately 2hain each planting years. ln every planting year, 5 m x 5 m plots were
made to measure mangrove density, height and root width. And then mud thickness and other
habitat elements, i.e. salinity, pH, N, P, K elements and waters temperature, were also measured.
Assessment on each plot was repeated 15 times systematically as replication. The distance
between plots was + 100 m, stretched along the shoreline.
In order to find out the role of mangrove rehabilitation towards the accumulation of mud
substrate, several analyses were conducted. The first was variant analysis to observe the
significance of mud thickness in each planting year. The second was regression-correlation
analysis between mangrove density and mud thickness. Besides that, in order to sharpen the
discussion of the above analysis results, it was necessary to conduct an analysis on the other
habitat elements which play a great role on mangrove growth.
RESULT AND DISCUSSION
The result of assessment on mangrove density showed that the decrease of density was parallel
with the increase of mangrove planting year. It was understandable because the older the
mangrove, the space competition occurred especially on its roots. The competition has caused the
death of shoved plants. The average assessment results are elaborated in the following table :
Table 1. Data measurement on different planting year of mangrove rehabilitation on the North
Coast of Brebes.
Planting Year
Density
Height
Root Width
Mud Thickness
?1
1999
8,4
178,3
IO7,I
2003
2006
222 | vrxAhgofhrtemational
rl,2
))
76,9
16,6
0,5
15,1
62,7
28,8
Conference on New Perspectives ofTiopical Fores Rehabilitation for Better Forest Functions and Management
In general' a5 mx 5 mplotwith2 mx.1-mplanting
spa:e canbe occupied by2;-22mangrove
seedlings' The result showed that the older
of trr. frtu'nti, g year, the lo-L. of the tree density.
However, the decreased of tree density
was alwayr ."*"r"t"a in with the increased
of the kee
height and root width' The difference of
tree derxity uoo t
in each planting year was not
"igh,
of root width .r,t*"a sigiincant
dirrirence rt was highry
::T:i#l
#Xi|l?,|1".ffi:1fl
The analysis of mud thickness showed a
significant difference between planting years.
The
variant analysis of mud thickness in each plaritlng
years showed a signif,rcant rate at S%olevel.
It
proved that mangrove root structure plays
u gr"it.ot" on the mud iccumulation. The data also
showed that within approximately 3 years
the mud thickness io...ur"J-io, about 40
cm. The
next analysis showed that vegetation density
was ttighty correlated with habitat elements (and
also mud thickness)' The analysis used was gackw;rd pfimination
procedure method
which
resulted in linier correlation oi lg.t%..The
regression equation is y : - 0.2xr. y
is
the
mud
thickness and X1 is the vegetation density.
Thelncreare of mua thickness was alway.
correlated
with the decreased of vegetation density (in.."rrirrg
oir"g"tution,s ages). It iwas understandable
because the increase of planting year caused
u gg1J. competitiol
vegetations. As a result,
the vegetation density decreasJcl but the
_among
root width increased and becanie
-i." "o-plicated. The
complicated root has increasd the accumulation
of mud substrate therefore the
mud thickness
also increased' The influenced of other habitat
elements was not significant, for example
salinity
level change usually fluctuated but it was still
on certain range lrrri.r,
be
tolerated
by
vegetation growth' The same things were
also occurred for te"mperature-"trld
urro
*ut".,
pH.
The
interesting was that'1"t9-*u: not aiy direct
correlation between N, p, K elements in
the
mud
and
the vegetation growth.(density, treiglt and
root width). The mud substrate was very unstable
because of the tides, hence it.was"almost
impossiur" ro, mangrove roots to optimally
absorb
those micro eleme-nts' A study by Poedjirurruio.
srrowed that it was phytoplankton that
lzooo;
utilized N' P and K elements mr its growth
Tlereiore, ine aensity of phytoplankton becomes
the
standard of waters fertility, which isirsually
indicated ilih" increase of mangrove growth.
CONCLUSION
1'
2'
There were significant thicknesses of mud
accumulation
mangrove rehabilitation (e.i. rggg, 2a03
and 2006).
in different planting years of
within ,-;;;;r, on average the
accumulated mud substrate was is 40 cm in
thickness,
The increase of mangrove's planting year (the
increased of vegetation,s ages) was
correlated
with the decreased of mangrove aensiiy and the
rrrc."area of mud thickness.
REFERENCES
Kathiresan' K' dan B'L' Bingham. 20^0L-.
Biology of Mangrove and Mangrove Ecosystems.
Advances in Marine Biology Vol. 40: g1_25I.
Macintosh' D'J' dan E'c' Ashion- 2002. A
Review of Mangrove Biodiversity conservation
and
Management' centre for Tropical Ecosystems
Research, university of Aarhus, Denmark.
Macnae' E'' 1968' A general account of the
fauna and flora of mangrove swamps
and forests in
the Indo-west pacific Region. Advances
in Marine Biology 6:73-270.
Poedjirahajoe' E' 1998' Perin mangrove
dalam Perbaikan Habitat Mangrove di pantai (Jtara
Kabupaten PemTl^a^ng Jawa Tengah. Builetin
Fakurtas Kehutanan uGM.
Poedjirahajoe, E" 2006' Klasifikaii Lahan
Potensial untuk Rehabilitasi Mangrove
di pantai
utara Jawa Tengah- Disertasi s3 program pasca
sarjana
uGM.
^
Sukardjo' s" 1993' Fungsi Proteksi Maigrove
; Distriiusi numeric akar jangkar Rhizopltora,
spp. Seminar Nasional Mangrove di Initiper yogtakarta
Proceedingoflnt€rnationalconferenceonNewPerspectivesofTropicalForestRehabilitationforBetterForestFtmctions
andManagtnrtt1223
CONFENENCE ON
NEW PERSPESrIVES OF TBOPICAL FONEST MN
FOB BETTER NONBST FT'NSTTONS ANI' M.{I,NAGEMENT
17*-19* October 2011
Faculty of Forestry Universitas Gadjah Mada
Yogyakarta, Indonesia
Editors:
Eko Bhakti Hardiyanto
Svein Solberg
Mitsuru Osaki
PROCEEDING OF INTERNATIONAL CONFERENCE ON
NEW PERSPECTIVES
OF TROPICAL F'OREST REHABILITATION FOR BETTER
FOREST FUNCTIONS
AND MANAGEMENT
Editors:
Eko Bhakti Hardiyanto
Universitas Gadjah Mada, yogyakarta, Indonesia
Svein Solberg
Norwegian Forest and Landscape Institute, Norway
Research Faculty
"rAHJi1il:,oJffi",u"
Faculty of Forestry
Universitas Gadjah Mada
2012
university, Japan
Proceeding of International Conference on New Perspectives of Tfopical Forest
Rehabilitation for Better Forest Functions and Management
t7th-tgth ocToBER
2011
Yogyakarta, Indonesia 2011
by Faculty of Forestry Universitas Gadjah Mada
Citation:
Hardiyanto , E.B, Solberg, S., Osaki, M. (eds.) 2012. Proceeding of International
Conference on New Perspectives of Tropical Forest Rehabilitation for Better Forest
Functions and Management, 17 th-lgth October 20 I l, Yogyakarta, Indonesia. Faculty of
Forestry Universitas Gadjah Mada.
Published by Faculty of Forestry, Universitas Gadjah Mada
Jl. Agro No l, Bulaksumur, Yogyakarta 55281
ISBN z 979-9924-66-9
Cover Design: GLM Printika
Printed in Indonesia
PREFACE
The degraded forest lands are of concern of rehabilitation programs, as they are usually the
centre areas of poverty, natural disaster (flood-drought) and climate change (hot spot of carbon
emission). However, fundamental understanding is prerequisite to provide a more generic principle
and technology to support successful rehabilitation in different forest types. Likewise, a more
contextual approach for the rehabilitation should also adopt the strategy to strengthen the sustainable
livelihood and more efficient timber processing at the local community level in order to reduce
deforestation and degradation. The international conference on New Perspective of Tropical Forest
Rehabilitation is proposed to strengthen an integrated approach in forest rehabilitation therefore
provide ecological landscape safety-net which are economically-viable and therefore could be selfsustaining in reducing pressure to forests.
The conference invites four international speakers in the field of tropical silviculture, tree
physiology and ecology from Indonesia, Australia, Norway, Japan and other international partners.
Participants are academicians, researchers, practitioners and students. Through the conference,
the participants will strengthen an integrated approach and establish new paradigm in managing
tropical forest rehabilitation for reducing deforestation and forest degradation.
The objectives of the conference are: 1). identitring the gap and updating the current status of
the methods and techniques on tropical forest rehabilitations, and 2). strengthening collaborations
with domestic and international parhrers in developing rehabilitation strategy for sustainable and
productive tropical forests.
The participants of the conference were from Japan, Malaysia, Hawaii USA, Norway and
Indonesia.
I would like to acknowledge all the authors for the paper contributed in this proceeding,
the
comment and review of the editors toward the publishment of this proceeding are also greatly
appreciated.
ThankYou
Organizing Committee
Proceeding of lntemational Conference on New Perspectives of Tropical Forest Rehabilitation for Better Forest Fuctions and Management
I
v
CONTENTS
Page
PREFACE
v
PHOTO SESSION
CONTENTS
vi
vii
ROBUST MONITORING TECHNIQUES
ON LARGE SCALE CARBON
DYNAMICS FOR REDD+ IN TROPICAL PEAILAND-FOREST
Mitsuru Osaki, Kazuyo Hirose, Noriyuki Kobayashi, Muhammad Evri and
Farhan Helmy (Keynote Speaker)
l-1s
FOREST BIOMASS MONITORING
Svein Solberg, Rasmus Astrup, Johannes Breidenbach and
Arnt Kristian
t6-22
Gjertsen (Keynote Speaker)
FORESTRY FOR PEOPLE: WE NEED A REFRESHED APPROACH
Sadanandan Nambiar (Keynote Speaker)
23-24
THE SOCIAL IMPACT OF REHABILITATION PROJECTS IN PROTECTED
AREAS: CASE STUDY AT SEBANGAU NATIONAL PARK CENTRAL
KALIMANTAN
Tri Wira Yuwati and Petrus Gunarso
2s-29
FOREST RESOURCE MANAGEMENT ON DAYAK KANAYATN COMMUNITY
Emi
Roslinda
30_33
ILENGI AGROFORESTRY SYSTEMS : A STUDY OF CONSERVATION AND
UTILIZNIION OF TREE SPECIES (Case Studies in South Dulamayo Village,
District Telaga, Gorontalo Province)
A. S. Hiola, N. Wijayanto, S.Adiwibowo, M. CoIIins
34-31
ON DIPTEROCARP TREE PLANTING IN
SMALLHOLDER RUBBER PLANTATION
Hesti L.Tata and Meine van Noordwijk
38-41
COMMUNITY-CENTERED FORE ST REHAB ILITA TION IN INDONESIA : PAST
EXPERIENCES AND FUTURE DIRECTION
Didik Suharjito
42-46
FARMERS PARTICIPATION
Proceeding of Intunaional Conference on New Perspectives of Tropical Forest Rehabilitation for Beuer Forest Functions and Maragemort
I
vii
rTHE ROLE OF MANGROVE ON MUD SUBSTRATE ACCUMULATION IN
REHABILITATED AREA ON THE NORTH COAST OF BREBES CENTRAL
JAVA
Erny
Poedjirahajoe
221-223
THE ROLE OF MANGROVE REHABILITATION ACTION ON CARBON
RESOURCE MANAGEMENT: A CASE STUDY FROM A MANGROVE
REHABILITATION SITE AT PEMALANG, THE NORTH COASTAL OF
CENTRAL JAVA, INDONESIA
Ni Putu Diana
Mahayani
224-228
LIST OF PARTICIPANT
t
xii
I froceoaAg of Intenmiunl Curferurce
on New Perpeciives ofTiopical Forest Rehabiliblion for Betrer Forest Functions and Maragement
THE ROLE OF MANGROVE ON MUD SUBSTRATE ACCUMULATION
IN REHABILITATED AREA ON THE NORTH COAST OF BREBES
CENTRAL JAVA
Erny poedjirahajoel
1)
F aculty of Forestry, Universitas Gadjah Mada, Y ogyakarta
(erjjr@yahcom)
ABSTRACT
The role of mangrove as land stabilizer can adds or increases of the land area towards the sea.
The result of mud accumulation which is called tanah timbul is useful for mangrove growth. This
research was a case study established in Brebes district, which is part of North Coast of
Cenkal
java. The objective was to determine the role and the ability of *urrgrove roots (Rhizophora
mucronata) in mud substrate accumulation on mangrove rehabilitation *"ur. The resear.h *u,
conducted by measuring root density, root width, tree density, tree height and tree diameter,
and
mud thickness in 5 m x 5 m square plots, with 15 replication. The plots were established in
different planting year,i.e., 1999, 2003 and 2006. Analysis of data was ionducted using variance
design and correlation regression on relationship between R.mucronata densities with mud
thickness. The result showed that the root srtructure and density of R.mucronata were able
to
accumulate mud subtrate, with an average of 28.8, 62.7 cm and, 107.1 cm on planting year
of
2006, 2003 and 1999 respectively. Base on the result, it can be concluded that the area of
manStrove rehabilitation area in Brebes's coast planted with R.mucronata has improved
the plant
density, which will eventually accumulate the mud substrate on every mangrove rehabilitation
area and expands land towards the sea.
INTRODUCTION
Mangrove is a swamp ecosystem which the vegetation live requires ahabitatcontaining salinity,
small wave, influenced by tides, the existence of mud and mud thickness. Those are the main
requirements which have to be fulfilled to ensure the existence of mangrove (poedjirahajoe,
1998). Mangrove's mud plays a great role on supplying micro elements to its ecosystem.
The
supply of micro elements by the mud is not stable because some of the micro elements are lost
by
river stream and ended in the sea. However, the most available micro elements which are used to
supply the energy are supplied by phytoplankton, those elements are resulted from its
photosynthesis. Therefore, in directly, the growth of mangrove could be detected through
the
density of phytoplankton. The productivity of mangrove is highly influenced by the produltivity
of phytoplankton (Poedjirah ajoe, 2006).
The tsunami has caused the loss of many lives. One of the causes is the loss of tidal forest
conservation area functions because of forest degradation for quite a long time. Currently,
some
efforts to restore the functions of mangrove in Indonesiaarebeing deviloped. One of them is
through rehabilitation of mangrove forest. Mangrove rehabilitation is intended to restore the
original functions of its ecosystem. Mangrove functions as a conservation, physically it is
capable in preventing the abration and intrusion of sea water and also stabilizes the soil. Through
its complicated root skucfure, one of mangrove species, e.i. Rhizhophora mucronata, which is
used as the main vegetation on rehabilitation program, has been able to kept the supply of both
organic and inorganic substances from the sea and the rivers (Macnae, 1968). 1.he supplies are in
the form of soft mud which are retained by mangrove roots and then accumulated, tirus forming
thick mud which becomes the characteristics of mangrove habitat.
Proceeding of Intemational Conference on New Perspectives ofTropical Forest Rehabilitation for Better Forest
Fr.mctions and Mur{Ierneltt
l22l
One of the species which is used as the main vegetation in mangrove forest rehabilitation is
Rhizophora, spp. This species has been determined by the Indonesian Forestry Department as
one of the species for mangrove forest rehabilitation vegetation. The decision was based on
Rhizophora's root structure which has aerial roots, complicated and able to endure sea waves and
to accumulate mud from the rivers and the sea (Sukardjo, 1993). Mangrove roots structure can
expand land formation towards the sea. As a result, the land becomes wider and more stable. The
great role of mangrove root strucfure towards its ecosystem is the perfect mangrove conservation
function for the land (Macintosh and Ashton,2002). Therefore, such ecological role should be
maintained as the support system for life on the land.
The accumulation of mud as mangrove substrate is very potential in forming new land so that
mangrove habitat is kept expanding. Besides that, mud also contains various organic substances
and micro elements thus mud thickness represents the availability of micro elements in mangrove
habitat (Kathiresan and Bingham. 2001). Such condition has to be kept developed so that
mangrove function as a conservation area can be quickly achieved. The objectives of this
research were to: (l)Find out the signif,rcance of mud thickness in mangrove rehabilitation area in
planting year of 1999,2003 and 2006. (2) Find out the influence of mangrove density on mud
thickness.
METHOD
This research was conducted in mangrove rehabilitation area on the North Coast of Brebes,
Central Java. The total area of mangrove rehabilitation is 10 ha consisting of various planting
years. This research was established only on planting year of 1999,2003 and2006 because it has
a fast growth. Tools which used in this research were ro11 meter, scaling pole, salt test, pH tester
and soil thermometer. The research was conducted through determining the width of sample area,
which in approximately 2hain each planting years. ln every planting year, 5 m x 5 m plots were
made to measure mangrove density, height and root width. And then mud thickness and other
habitat elements, i.e. salinity, pH, N, P, K elements and waters temperature, were also measured.
Assessment on each plot was repeated 15 times systematically as replication. The distance
between plots was + 100 m, stretched along the shoreline.
In order to find out the role of mangrove rehabilitation towards the accumulation of mud
substrate, several analyses were conducted. The first was variant analysis to observe the
significance of mud thickness in each planting year. The second was regression-correlation
analysis between mangrove density and mud thickness. Besides that, in order to sharpen the
discussion of the above analysis results, it was necessary to conduct an analysis on the other
habitat elements which play a great role on mangrove growth.
RESULT AND DISCUSSION
The result of assessment on mangrove density showed that the decrease of density was parallel
with the increase of mangrove planting year. It was understandable because the older the
mangrove, the space competition occurred especially on its roots. The competition has caused the
death of shoved plants. The average assessment results are elaborated in the following table :
Table 1. Data measurement on different planting year of mangrove rehabilitation on the North
Coast of Brebes.
Planting Year
Density
Height
Root Width
Mud Thickness
?1
1999
8,4
178,3
IO7,I
2003
2006
222 | vrxAhgofhrtemational
rl,2
))
76,9
16,6
0,5
15,1
62,7
28,8
Conference on New Perspectives ofTiopical Fores Rehabilitation for Better Forest Functions and Management
In general' a5 mx 5 mplotwith2 mx.1-mplanting
spa:e canbe occupied by2;-22mangrove
seedlings' The result showed that the older
of trr. frtu'nti, g year, the lo-L. of the tree density.
However, the decreased of tree density
was alwayr ."*"r"t"a in with the increased
of the kee
height and root width' The difference of
tree derxity uoo t
in each planting year was not
"igh,
of root width .r,t*"a sigiincant
dirrirence rt was highry
::T:i#l
#Xi|l?,|1".ffi:1fl
The analysis of mud thickness showed a
significant difference between planting years.
The
variant analysis of mud thickness in each plaritlng
years showed a signif,rcant rate at S%olevel.
It
proved that mangrove root structure plays
u gr"it.ot" on the mud iccumulation. The data also
showed that within approximately 3 years
the mud thickness io...ur"J-io, about 40
cm. The
next analysis showed that vegetation density
was ttighty correlated with habitat elements (and
also mud thickness)' The analysis used was gackw;rd pfimination
procedure method
which
resulted in linier correlation oi lg.t%..The
regression equation is y : - 0.2xr. y
is
the
mud
thickness and X1 is the vegetation density.
Thelncreare of mua thickness was alway.
correlated
with the decreased of vegetation density (in.."rrirrg
oir"g"tution,s ages). It iwas understandable
because the increase of planting year caused
u gg1J. competitiol
vegetations. As a result,
the vegetation density decreasJcl but the
_among
root width increased and becanie
-i." "o-plicated. The
complicated root has increasd the accumulation
of mud substrate therefore the
mud thickness
also increased' The influenced of other habitat
elements was not significant, for example
salinity
level change usually fluctuated but it was still
on certain range lrrri.r,
be
tolerated
by
vegetation growth' The same things were
also occurred for te"mperature-"trld
urro
*ut".,
pH.
The
interesting was that'1"t9-*u: not aiy direct
correlation between N, p, K elements in
the
mud
and
the vegetation growth.(density, treiglt and
root width). The mud substrate was very unstable
because of the tides, hence it.was"almost
impossiur" ro, mangrove roots to optimally
absorb
those micro eleme-nts' A study by Poedjirurruio.
srrowed that it was phytoplankton that
lzooo;
utilized N' P and K elements mr its growth
Tlereiore, ine aensity of phytoplankton becomes
the
standard of waters fertility, which isirsually
indicated ilih" increase of mangrove growth.
CONCLUSION
1'
2'
There were significant thicknesses of mud
accumulation
mangrove rehabilitation (e.i. rggg, 2a03
and 2006).
in different planting years of
within ,-;;;;r, on average the
accumulated mud substrate was is 40 cm in
thickness,
The increase of mangrove's planting year (the
increased of vegetation,s ages) was
correlated
with the decreased of mangrove aensiiy and the
rrrc."area of mud thickness.
REFERENCES
Kathiresan' K' dan B'L' Bingham. 20^0L-.
Biology of Mangrove and Mangrove Ecosystems.
Advances in Marine Biology Vol. 40: g1_25I.
Macintosh' D'J' dan E'c' Ashion- 2002. A
Review of Mangrove Biodiversity conservation
and
Management' centre for Tropical Ecosystems
Research, university of Aarhus, Denmark.
Macnae' E'' 1968' A general account of the
fauna and flora of mangrove swamps
and forests in
the Indo-west pacific Region. Advances
in Marine Biology 6:73-270.
Poedjirahajoe' E' 1998' Perin mangrove
dalam Perbaikan Habitat Mangrove di pantai (Jtara
Kabupaten PemTl^a^ng Jawa Tengah. Builetin
Fakurtas Kehutanan uGM.
Poedjirahajoe, E" 2006' Klasifikaii Lahan
Potensial untuk Rehabilitasi Mangrove
di pantai
utara Jawa Tengah- Disertasi s3 program pasca
sarjana
uGM.
^
Sukardjo' s" 1993' Fungsi Proteksi Maigrove
; Distriiusi numeric akar jangkar Rhizopltora,
spp. Seminar Nasional Mangrove di Initiper yogtakarta
Proceedingoflnt€rnationalconferenceonNewPerspectivesofTropicalForestRehabilitationforBetterForestFtmctions
andManagtnrtt1223