o_19ko2dt161ng2j4e1tgnoqv1s45a.pdf

LEE et al (2007)
to Lee et al. (2004) using a GENEAMP PCR System 9700 (Applied Biosystems) and an ABI
PRISM 377 DNA Sequencer (Applied Biosystems), respectively.
Data Analysis
Allelic frequencies were determined for each locus in each population (individuals with dbh
>25 cm were used to represent the Sungai Pinang population). Based on these data, the following
levels of genetic diversity were estimated: average number of alleles per locus (A a
), allelic
richness (R s
; Petit et al. 1998), gene diversity (H e
; Nei 1987) and fixation index (F is
; Nei 1987).
Spatial genetic structure in the Sungai Pinang was evaluated using Moran’s I coefficient (Moran
1950). An indication of the trends in spatial scale of genetic substructuring was obtained using
correlograms (Sokal & Oden 1978). A permutation procedure using Monte Carlo simulation
was applied to test significant deviation from random distribution of each calculated measure
(Manly 1997). Population genetic structure was quantified using R-statistics (R st
; Slatkin 1995,
Goodman 1997). Relatedness among populations was quantified using D A
genetic distances
(Nei et al. 1983) for pairwise comparison of divergence between populations and cluster analysis
on genetic distances via the neighbor-joining (NJ) method (Saitou & Nei 1987). Relative strength
of the nodes was determined using bootstrapping analysis (1000 replicates). For the direct
estimation of gene flow, parentage was determined by simple exclusion method and likelihoodbased
approach in the program CERVUS 2.0 (Marshall et al. 1998). The breeding unit parameters
were estimated according to Nason et al. (1998). The minimum population size to maintain
current level of genetic diversity was estimated according to Lee et al. (2002).
Ecology
RESULTS
The species was present in five forest reserves, i.e., Sungai Pinang, Pangkor Selatan, Segari
Melintang, Lumut and Teluk Muroh, which were confined to an area of approximately 313
km². As the two island populations (Sungai Pinang and Pangkor Selatan) are separated from
the mainland by the Straits of Dinding, they must have been isolated from mainland populations
many thousand years ago. Among the three mainland populations, no distinctive geographical
barrier divided the Lumut and Teluk Muroh but the Segari Melintang population was separated
by the Manjung River.
Within these reserves, S. lumutensis occurs as small patches in a general matrix of coastal hill
dipterocarp forest, usually at >100 m asl. Isolated individuals are occasionally seen but rare.
The species is most often a subcanopy to emergent tree. Symington (1943) reported that the
species seldom exceeded 50 cm dbh but in Sungai Pinang and Lumut, four trees >100 cm dbh
were encountered. The preferred habitat for these five populations appears to be dry coastal hill
forest on moderate-fertility soils, in microclimates where drainage is good or where high soil
moisture levels cannot be permanently maintained. The number of large trees was estimated to
be less than 500 for these five populations. Although the number of large trees was low in each
of the populations, progressively larger numbers of associated saplings and seedlings were
observed scattered surrounding the large trees in each of these populations. We also identified
the following potentially major threats for population endangerment: logging activities (Segari
Melintang), excavation for stones (quarry) and conversion to oil palm plantations (Lumut and
Teluk Muroh), and land development for tourism (Pangkor Selatan and Sungai Pinang).
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