ARTIKEL ILMIAH
PROGRAM PENELITIAN FUNDAMENTAL DI PERGURUAN TINGGI
TAHUN ANGGARAN 2008
JUDUL
STRATEGI REGENERASI DARI BEBERAPA ANAKAN
POHON SETELAH PEMBALAKAN LIAR DI BUKIT PINANGPINANG DAN PERANANNYA DALAM UPAYA
MEREHABILITASI HUTAN YANG TERDEGRADASI
OLEH
Dr. Erizal Mukhtar, MSc
Dibiayai oleh :
Direktorat Jenderal Pendidikan Tinggi
Departemen Pendidikan Nasioanl
Sesuai dengan Surat Perjanjian Pelaksanaan Pekerjaan Penelitian
Nomor: 005/SP2H/PP/DP2M/III/2008
Tanggal 6 Maret 2008
FAKULTAS MATEMATIKAN DAN ILMU PENGETAHUAN ALAM
UNIVERSITAS ANDALAS
PADANG
2008
1
Survival and Growth of Several Important Juveniles Tree Species in a
Tropical Rain Forest, West Sumatra
Erizal Mukhtar
Department of Biology, Faculty of Mathematics and Natural Sciences,
Andalas University, Padang 25163, West Sumatra, Indonesia
ABSTRACT
Survival and Growth rate of juveniles tree species in a tropical rainforest, West Sumatra, was measured for
seven tree species over 13 year period in 1-ha plot of tropical rain forest in Ulu Gadut, West Sumatra,
Indonesia. All individuals with dbh < 8 cm were sampled in 1989-1998 and 2002. The highest Survival rate
of seedling was observed for Swintonia schwenkii and followed by Cleistanthus glandulosus and
Gonystylus forbesii. The lowest survival rate was observed for Grewia florida. Relative Height Growth
Rate (RHGR) were various between emergent, canopy and subcanopy tree. The highest RHGR was
observed for emergent tree species, S. schwenkii. Whereas between canopy species, Hopea dryobalanoides
was showed higher RHGR than Calophyllum soulattri. Furthermore, S. schwenkii as emergent tree
species showed highest performance in Integrated Response Index (IRI). The relationship between their
performances in the forest stand was also discussed in this paper.
Key Words : Survival, RHGR, IRI, seedling, Ulu Gadut forest.
INTRODUCTION
Regeneration is a key process for the existence of species in the community. It is also a critical
part of forest management, because regeneration maintains desired species composition and
stocking after biotic and abiotic disturbances. Various studies on regeneration of trees have
been carried out in survival and growth. For example, the rate of forest regeneration depends
largely on the growth rates and survival of native species that are planted or arrive on their
own (Clark et al., 1999; Quintana-Ascencio et al, 2004) and large differences in seedling
growth and survival of several species in response to spatial heterogeneity in
microenvironments (Beckage and Clark, 2003).
We have monitored the population of major species at 1-ha permanent plots of a
foothill rain forest in Ulu Gadut, West Sumatra since 1980. Spatial distribution pattern of
major species in this forest have been revealed and their regeneration mechanisms were
discussed with demographic data (Suzuki & Kohyama, 1991; Kohyama et al., 1994; Mukhtar
et al., 1992, 1998). This study follows the above previous paper observing the regeneration
mechanisms of several tree species in respect to their survival and growth rate. We aimed to
clarify species characteristics survival and growth rates of juveniles in differences stage of the
major tree species in this forest.
MATERIALS AND METHODS
Study site
This study was carried out at 1-ha permanent plot, named Pinang-pinang plot in a
foothill forest of Mt. Gadut (Lat. 0o 55’ S, Long. 100o 30’ E), 18 km east from Padang, West
Sumatra, Indonesia. The elevation ranged from 490 m to 520 m in altitude. This plot is
covered primarily by matured trees occurring in patches with sporadic gap and regrowth
patches. Details of stand descriptions could be referred to the previous papers (Kohyama et
al., 1989; Yoneda et al., 1990; Mukhtar et al, 1992; 1998)
2
Study species
We chosen 7 species which all these species are common and dominant in Ulu Gadut
forest floor. The species were Swintonia schwenkii T & B (Anacardiaceae), Calophyllum
soulattri Burm (Guttiferae), Hopea dryobalanoides Miq. (Dipterocarpaceae), Cleistanthus
glandulosus Jabl. (Euphorbiaceae), Mastixia trichotoma Bl. (Cornaceae), Grewia florida Miq.
(Tiliaceae) and Gonystylus forbesii Gilg. (Thymelaeceae). The species characteristics of seven
tree species in forest stand are shown in Table 1.
Observation for seedling dynamics
All juveniles selected tree species were measured and mapped into a grid of 115 subplots of 10 x 10 m. The trees were marked and the species were identified. In September 1989,
we were carried out first census of individuals for representative tree species in the plot
permanent. The juveniles were re-sampled on September 1998 and on September 2002 in a
second and the third census, respectively. Their positions and tree height were also measured
at the first census and it recorded position make easily for next measurement.
Calculation of Survival Rate and Relative Growth Rate
Survival rate was calculated in two different census intervals, 1989-1998 and 19892002. For each tree species, we analyzed survival rate in each year with respect to juveniles
size and distance to the nearest conspecific adult.
Survival rates were determined as : Survival = (Nt/No)/ ∆t x 100 %
where No number of population count at the beginning of the measurement interval, Nt =
number of emerged among the initial population, ∆t = measurement interval between census
(Stephanie and Jean-Francois, 2000; Quintana-Ascencio et al., 2004; Munemitsu and Shiro,
2005).
Relative Height Growth Rate (RHGR) could obtained by the following formula :
RHGR = [ ln Ht1 – ln Ht2 ]/ ∆t
where Ht1 and Ht2 are juvenile height in t1 and t2, and the duration (∆t), respectively (Hunt,
1982; Beckage and Clark, 2003; Quintana-Ascencio et al., 2004).
Integrated Response Index
In order to assess relative establishment success among the species, a composite
performance index was used to integrate the contributions of regeneration responses of
survival and growth. The relative value of the index indicates the expected success of each
species at their habitat. The Integrated Response Index (IRI) was calculated as IRI = Survival
x RHGR (De Steven, 1991; Quaintana-Ascencio et al., 2004).
RESULTS
Vertical structure
Figure 1 is shown the height distributions of seven tree species in Pinang-pinang plot.
The result shows a time trend of the population number during 13 years since 1989. The
population was decreased gradually as the height class increased. The distributions patterns
were founded majority (six species) in L-shaped whereas the distribution pattern for
Gonystylus forbesii were changed to Bell-shaped at the second and third census measurement.
Furthermore, the numbers of population were dominant at seedling stage (H=0-100 cm) for
both census interval. The highest population number at seedling stage were observed for
Calophyllum soulattri and followed by Cleistanthus glandulosus and Swintonia schwenkii.
The lowest population number was observed for Grewia florida.
3
Number of Individu
200
Swintonia schwenk iii
Calophyllum soulattri
2800
2400
150
2000
1600
100
1200
800
50
400
> 1000
801-900
701-800
601-700
501-600
401-500
301-400
201-300
901-1000
801-900
901-1000
> 1000
801-900
901-1000
> 1000
701-800
601-700
501-600
401-500
301-400
201-300
Cleistanthus glandulosus
500
Gonystylus forbesii
101-200
0-100
0-100
> 1000
801-900
901-1000
701-800
0
601-700
0
501-600
50
101-200
> 1000
801-900
901-1000
701-800
601-700
501-600
401-500
50
401-500
100
301-400
100
201-300
150
101-200
Grewia florida
200
150
200
400
150
300
100
200
50
100
701-800
601-700
501-600
401-500
301-400
201-300
0
0-100
> 1000
801-900
901-1000
701-800
601-700
501-600
401-500
301-400
201-300
101-200
0-100
0
101-200
Number of Individu
301-400
101-200
Hopea dryobalanoides
0-100
Number of Individu
200
201-300
0
0-100
0
Number of Individu
Height class (cm)
Mastixia trichotoma
300
Population 1989
200
Population 1998
Populationi 2008
100
> 1000
801-900
901-1000
701-800
601-700
501-600
401-500
301-400
201-300
101-200
0-100
0
Height class (cm)
Figure 1. The height class distribution of seven tree species based on seedling stage (H=0-100
cm), sapling stage (H=101-400 cm) and pole stage (H=400-1000 cm)
Survival rate
Survival rate was differences among seven tree species as shown in Fig. 2. In general
the result showed that survival rate was highest in the seedling stage and rapidly increased as
the height class increased. Among seven tree species studies showed that the similar survival
pattern between two interval censuses. The highest survival was observed in small height class
(seedling, < 100 cm in height) for Swintonia schwenkii and followed by Cleistanthus
glandulosus and Gonystylus forbesii. Furthermore, Calophyllum soulattri, Hopea
dryobalanoides and Mastixia trichotoma showed intermediate. The lowest survival rate was
observed for Grewia. The survival rate pattern was also similar for the second census interval.
4
3
0
0
6
3
3
0
0
12
0-100
101-1000
12
Gonystylus forbesii
6
3
3
0
0
> 1000
6
101-1000
9
0-100
9
101-1000
101-1000
6
> 1000
9
Grewia florida
Cleistanthus glandulosus
101-1000
> 1000
12
9
0-100
Survival (%/yr)
Hopea dryobalanoides
> 1000
3
> 1000
6
> 1000
6
Calophyllum soulattri
0-100
9
101-1000
9
12
Survival (%/yr)
12
0-100
Swintonia schwenkii
0-100
Survival (%/yr)
12
Height class (cm)
Survival (%/yr)
12
Mastixia trichotoma
SURVIVAL 1989-1998
9
SURVIVAL 1989-2008
6
3
> 1000
1011000
0-100
0
Height class (cm)
Figure 2. Frequency distribution of survival rate for seven tree species in two different census
interval.
5
> 1000
801-900
901-1000
701-800
601-700
501-600
401-500
301-400
201-300
701-800
801-900
901-1000
701-800
801-900
901-1000
601-700
501-600
401-500
201-300
301-400
> 1000
601-700
501-600
401-500
301-400
> 1000
901-1000
801-900
0
701-800
0
601-700
3
501-600
3
401-500
6
301-400
6
201-300
9
101-200
9
Cleistanthus glandulosus
201-300
12
Gonystylus forbesii
101-200
0-100
0-100
901-1000
801-900
0
701-800
0
601-700
3
501-600
3
401-500
6
301-400
6
201-300
9
0-100
Grewia florida
12
9
0-100
Calophyllum soulattri
101-200
> 1000
101-200
Hopea dryobalanoides
101-200
RHGR (cm/cm/yr)
12
801-900
0
901-1000
0
701-800
3
601-700
3
501-600
6
401-500
6
301-400
9
201-300
9
12
RHGR (cm/cm/yr)
12
101-200
Swintonia schwenkii
0-100
12
0-100
RHGR (cm/cm/yr)
Growth rate
In general Relative Height Growth Rate (RHGR) was decreased as the hight class
increasead as shon in Figure 3. The highest RHGR was observed for Grewia florida for the
first census interval but at the second census interval the rate become lowest one. At the
second census interval the highest RHGR was observed at Swintonia schwenkii. Furthermore,
Hopea dryobalanoides, Gonystylus forbesii, were showed intermediate in both interval
census. Mastixia trichotoma showed higher RHGR at first census but showed the lower one at
the second census. From these results it can be concluded that the long term survey for
survival rate is necessary for clarify exactly the growth rate of each species.
Height class (cm)
RHGR (cm/cm/yr)
12
Mastixia trichotoma
RHGR 1989-1998
9
RHGR 1989-2008
6
3
> 1000
901-1000
801-900
701-800
601-700
501-600
401-500
301-400
201-300
101-200
0-100
0
Height class (cm)
Figure 3. Relative Growth Rate of seven main tree species.
6
0
0
Hopea dryobalanoides
40
30
30
20
20
10
10
0
0
50
101-1000
50
Gonystylus forbesii
30
30
20
20
10
10
0
0
> 1000
40
101-1000
40
0-100
Grewia florida
0-100
40
101-1000
0-100
50
101-1000
50
> 1000
10
Calophyllum soulattri
Cleistanthus glandulosus
> 1000
20
10
> 1000
30
20
101-1000
40
30
0-100
Integrated Response Index
Integrated Response Index
50
40
101-1000
Swintonia schwenkii
0-100
50
0-100
Integrated Response Index
Integrated Response Index
Based on the values the Integrated Response Index (IRI) showed that Swintonia as
emergent tree species have higher response in their performance compared than another tree
species. This result indicated that the characteristics of this species in order to reach upper
layer of stand forest. Whereeas between canopy tree species, Hopea dryobalanoides showed
higher IRI than Calophyllum soulattri. Furthermore, between subcanopy species Cleistanthus
glandulosus and Gonystylus forbesii showed higher IRI than that two other subcanopy species.
The pattern was similar in both two surveys.
Height class (cm)
Integrated Response Index
50
Mastixia trichotoma
40
IRI 1989-1998
30
IRI 1989-2008
20
10
> 1000
101-1000
0-100
0
He ight class (cm)
Figure 4. Integrated Response Index (IRI) from seven main tree species
7
DISCUSSION
Our discussion will focused on their relationship with statue in the forest stand.
Various pattern of survival rate were found between emergent, canopy and subcanopy tree
species. Grewia florida and Mastixia trichotoma as subcanopy tree species have performance
the lower survival for seedling as shown in Figure 2. According to Kohyama et al., (1994)
both of two species were recognized to be more sensitive to gap dynamics than Hopea
dryobalanoides, Gonystylus forbesii and Cleistanthus glandulosus.
In our data founded that G. forbesii and C. glandulosus also as subcanopy tree
species showed higher survival for seedling stage. Both canopy tree species Calophyllum
soulattri showed the lowest in survival rate for seedling. The higher RHGR was observed for
emergent tree species, Swintonia schwenkii. Whereas between canopy species Hopea
dryobalanoides showed higher growth rate compare than Calophyllum soulattri. These result
concluded that the subcanopy species showed their strategies in order to reach upper part of
the forest canopy.
The regeneration behaviour of each tree species is controlled by many factors such as
distance from the mother tree, topography and their statue in the forest stand. In our previous
result (Mukhtar et al., 1998) we found clear relationship between mortality rate and distance
from the mother tree of C. soulattri, eventhough the measurement in short time (five years).
Similar result was also found by Suzuki and Kohyama (1991) for Swintonia schwenkii microenvironment in the area around mother tree seemed not to be suitable for the survival of the
seedlings. Many factors affected to low survival rate around mother tree have been proposed
for example, Suzuki and Kohyama (1991) conluded that the wings of Swintonia fruits play a
significant rolw by dispersing the fruit under the crown of other species, and escaping from
hazardous place for seedling survival around mother trees.
Most tropical rain forest tree species have strongly aggregated spatial distribution
pattern. The species distributions are also strongly aggregated with respect to variation in soil
nutrient status (Clark et al., 1998). Palmiotto et al., (2004) in Lambir, Borneo founded that
Swintonia schwenkii naturally aggregated on low-fertility humult ultisol and Hopea
dryobalanoides on moderate-fertility udult ultisols. Furthermore, in the same forest, Lambir,
Russo et al., (2005) was also found that growth and mortality were lowest on the poorer soil
(sandy loam). Their result concluded that Hopea dryobalanoides had significantly higher
survival rates in udult than in humult soils in gaps area. Whereas for Swintonia schwenkii had
no significant differences in survival rates between soils or light level. In our study area,
according to Hermansah et al., (2002a,b) mentioned that nitrogen (N), magnesium (Mg) and
sulfur (S) were highest concentration in Pinang-pinang plot. High diversity of tree species and
the diverse nutritional characteristics of tree species contributed to the variation of soil
nutritional status and to edaphic niche. However, in our result, Integrated Response Index as
shown in Fig 4, showed more clear the species characteristics in their performance in growth
and survival in order to reach position in the forest stand.
ACKNOWLEDGEMENTS
We would like to express our appreciation to Prof (Emiretus) Mitsuru Hotta of
Kagoshima University, Prof (Emiretus) Kazuhiko Ogino of Ehime University and Prof
Tsuyoshi Yoneda for their initiation and valuable advices for this long term research. This
study is based on a long-term observation and Prof (Emiretus) Syunzo Kawamura of Kyoto
University had supported this study throughout the period under Sumatra Nature Study (SNS)
Project and Field Biology Research and Training (FBRT) Project in Padang. We also thanks
to Prof Eizi Suzuki (Kagoshima University) and Takeshi Kohyama (Hokkaido University) for
their permission for use their initial data. Finally we would like to thank to DGHE of
Indonesian Government through Basic Science financial support fiscal year 2008.
8
REFERENCE
Beckage, B and J.S. Clark. 2003. Seedling survival and growth of three forest tree species :
The role of spatial heterogeneity. Ecology 84 (7); 1849-1861.
Clark, D.B; Clark,D.A and I.M. Read. 1998. Edaphic variation and mesoscale distribution of
tree species in a neotropical rain forest. Journal of Ecology 86; 101-112.
Clark, J.S; M. Silman; R. Kern; E. Macklin and J.Hillerislambers. 1999. Seed dispersal near
and far : Patterns across temperate and tropical forests. Ecology 80 (5); 1475-1494.
Condit, R; S.P. Hubbell and R.P. Foster. 1995. Mortality rates of 205 neotropical tree and
shrub species and the impact of a severe drought. Ecological Monograph
65(4);419-439.
De Steven, D. 1991. Experiments on mechanisms of tree establishment in old-field succession
: seedling survival and growth. Ecology 71; 1076-1088.
Hermansah; T. Masunaga; T. Wakatsuki and Alfizar. 2002a. Dynamics of litter production
and its quality in relation to climatic factors in a super wet tropical rain forest plot,
West Sumatra, Indonesia. Tropics 12(2);115-130..
Hermansah; T. Masunaga; T. Wakatsuki and Alfizar. 2002b. Micro spatial distribution pattern
of litterfall and nutrient flux in relation to soil chemical properties in a super wet
tropical rain forest plot, West Sumatra, Indonesia. Tropics 12(2);131-146.
Hunt, R. 1982. Plant Growth Curves. The Functional Approach to Plant Growth Analysis.
University Park Press, Baltimore.
Kohyama, T; E. Suzuki and M. Hotta. 1994. Spatial Distribution Pattern of Representative
Tree Species in A Foothill Rain Forest In West Sumatra. Tropics 4 (1); 1-15.
Mukhtar, E; E. Suzuki; T. Kohyama and M. Rahman. 1992. Regeneration Process of a Climax
Species Calophylllum cf. soulattri in Tropical Rain Forest of West Sumatra.
Tropics 2(1); 1-12
Mukhtar, E; T. Yoneda, Zalfiati and M. Rahman. 1998. Regeneration Process of a Climax
Species Calophylllum cf. soulattri in Tropical Rain Forest of West Sumatra :
Population Dynamics of a Cohort from Mast Fruiting in 1981. Tropics 7(3/4);
183-194
Munemitsu, A and S. Tsuyuzaki. 2005. Tree seedling performance in microhabitats along an
elevation gradient on Mount Koma, Japan. Journal of Vegetation Science 16; 647654.
Nathan, R; G. Perry; J.T. Cronin; A.F. Strand and M.J. Cain. 2003. Methods for estimating
long-distance dispersal. Oikos 103; 261-273.
Nathan, R and R. Casagrand. 2004. A simple mechanistic model of seed dispersal, predation
and plant establishment: Janzen-Connell and beyond. Journal of Ecology 92; 733746.
Ohtani, S and F. Koike. 2005. Implication of the 19th landscape patterns for the recovery of
Fagus crenata forests. Applied Vegetation Science 8; 125-132.
Palmiotto, P.A; S.J. Davies; K.A. Vogt; M.A. Ashton; D.J. Vogt and P.S. Ashton. 2004. Soilrelated habitat specialization in dipterocarp rain forest tree species in Borneo.
Journal of Ecology 92; 609-623.
Pott, M.D; P.S. Ashton; L.S. Kaufman and J.B. Plotkin. 2002. Habitat patterns in tropical
rainforests: a comparison of 105 plots in Northwest Borneo. Ecology 83; 27822797.
Quintana-Ascensio, P.F; N. Ramirez-Marcial; M. Gonzalez-Espinosa and M. Martinez-Ico.
2004. Sapling survival and growth of coniferous and broad-leaved trees in
successional highland habitats in Mexico. Applied Vegetation Science 7; 81-88.
Russo, S.E; S.J. Davies; D.A. King and S. Tan. 2005. Soil-related performance variation and
distributions of tree species in a Bornean rain forest. Journal of Ecology 93; 879889.
9
Sheil, D and R.M. May. 1996. Mortality and recruitment rate evaluation in heterogeneous
tropical forest. Journal of Ecology 84; 91-100.
Skarpaas, O; K. Shea and J.M. Bullock. 2005. Optimizing dispersal study design by Monte
Carlo simulation. Journal of Applied Ecology 42; 731-739.
Suzuki, E and T. Kohyama. 1991. Spatial Distributions Of Wind-Dispersed Fruits And Trees
Of Swintonia schwenkii In A Tropical Forest Of West Sumatra. Tropics 1(2/3);
131-142.
Topoliantz, S and P. Jean-Francois. 2000. Influence of site condition on the survival of Fagus
sylvatica seedlings in an old-growth beech forest. Journal of Vegetation Science
11; 369-374.
Yoneda, T; R. Tamin and K. Ogino. 1990. Dynamics Of Aboveground Big Woody Organs In
A Foothill Dipterocarp Forest, West Sumatra, Indonesia. Ecological Research 5;
111-130.
Yoneda, T; K. Ogino; T. Kohyama, R. Tamin, Syahbuddin and M. Rahman. 1994. Horizontal
Variance Of Stand Structure And Productivity In A Tropical Foothill Rain Forest,
West Sumatra, Indonesia. Tropics 4(1); 17-33.
10