THE MALAYSIAN FORESTER 72 (1): 117-133 (2009) COMMUNITY STRUCTURE, DIVERSITY AND BIOMASS OF IN TWO FOREST SUBTYPES OF PEKAN FOREST RESERVE, ,

ISMAIL, P., 1 * NIZAM, M.S., 2 FARIDAH-HANUM, I., 3 1 1 1 KHALI AZIZ, H. , SHAMSUDIN, I., SAMSUDIN, M. AND A. LATIFF 2

1 Forest Research Institute Malaysia (FRIM), Kepong 52109 , Malaysia. 2 School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia. 3 Faculty of Forestry, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. * Corresponding author: [email protected]

Abstract: Two one-ha ecological plots representing Kempas-Ramin-Durian and Durian-Nyatoh forest subtypes were established in Compartment 156 and Compartment 200, respectively at Pekan Forest Reserve, Pahang to determine community structure, diversity and biomass of trees. All trees of 10 cm diameter at breast height and above were enumerated in the plots. Results showed that although stocking was almost similar in the two forest subtypes, the basal area, volume and total tree biomass were higher in the Kempas-Ramin-Durian subtype. Shannon-Weiner diversity index, H’ obtained in the Durian-Nyatoh subtype was however, significantly higher (p<0.05) than Kempas-Ramin Durian subtype. Morisita’s Index of Dispersion (Id) showed a random distribution pattern for both forest subtypes.

Key words: Forest subtypes, taxonomic composition, community structure,

INTRODUCTION

The peat swamp forests (PSF) of the Pekan District, Pahang, which included the Pekan Forest Reserve (FR) was first classified using the photo-interpretation method (Chong 1965). A more comprehensive work in the South-East Pahang Peat Swamp Forest (SEPPSF) by Blackett and Wollensen (2005) recognized 13 forest subtypes; these subtypes were further refined by UNDP/GEF (2006) based on distribution and dominance. Khali Aziz et al. (2007) described stand characteristics of tree communities in a Ramin-Bintangor forest subtype of SEPPSF as rich with commercial timber species such as Gonystylus bancanus (Ramin melawis) , Calophyllum ferrugineum (Bintangor) , Shorea platycarpa (Meranti Paya) , Tetramerista glabra (Punah), (Kempas) and Durio carinatus (Durian paya) . However, a detailed description on community structure of the remaining forest subtypes are still lacking, especially those with less economic values. It is deemed essential to obtain more ecological information on other forest subtypes in order to give a better picture of the Pekan FR for the relevant authorities to take significant management actions for achieving sustainable forest management.

117 P. Ismail et al.

MATERIALS AND METHODS

Plot Establishment

The ecological plots were established in Compartment 156 for Kempas-Ramin- Durian subtype and Compartment 200 for Durian-Nyatoh subtype in Pekan FR (Figures 1 and 2). A one-hectare plot of 100 x 100 m was established; these plots were further divided into 25 contiguous subplots of 20 m x 20 m. All trees of 10 cm diameter at breast height (dbh) and above were identified, tagged, mapped and measured using a diameter tape at 1.3 m above the ground.

Figure 1 . Location of Pekan FR in the South-East Pahang Peat Swamp Forest (SEPPSF).

Data Analysis

All trees enumerated in the ecological plots were summarized for overall taxonomic composition and quantitative data were analysed to determine abundance. These include determination of basal area, as well as calculating the density and frequency of occurrence of each species. Tree basal area ( BA ) was calculated using the equation as follows: BA = [ π x ( d2)/40000] (unit: m 2), where d is the diameter at breast height and π=3.142. The tree volume was calculated using an equation as follows: volume = BA x mht x 0.65 (unit: m 3), where mht is the merchantable bole height in meter. The 0.65 is a presumed factor applies to all trees (JPSM 1997).

118 THE MALAYSIAN FORESTER

Zone Forest subtype RAM Ramin-Bintangor ( Gonystylus-Calophyllum ) MDX2 Mixed Kempas-Ramin-Durian ( Koompassia-Gonystylus- Durio ) BTG Bintangor ( Calophyllum ) BTGD Bintangor ( Calophyllum ) and Kelat ( Syzygium ) MERANTI Meranti paya ( Shorea ) D/N Durian-Nyatoh ( Durio-Madhuca ) MAH Kempas-Mahang-Durian (Koompassia-Macaranga-Durio ) DSB Logged-over and open areas RIV Riverine and open areas

Figure 2. Location of the one-ha ecological plots in Compartments 156 and 200 of Pekan FR , and the forest suptypes based on UNDP/GEF (2006).

Distribution analyses were carried out using Morisita’s Dispersion Index (Morisita 1959), while two indices, Importance Value Index ( IV i) (Brower et al. 1997) and Shannon-Weiner Diversity Index ( H’ ) (Shannon & Weaver 1949) were also calculated to determine species importance and species diversity of the forest subtypes, respectively. The IV i was calculated by summing up the values of relative density ( RD ), relative dominance (based on basal area) ( RB ), and relative frequency

119 P. Ismail et al.

(RF ) of each species or [ IV i = RD + RB + RF )/3]; whilst the Shannon-Wiener Diversity Index ( H’ ) was calculated using formula as follows: s

H '= −∑ pi ln pi , where i=1 s = the number of species; pi = the proportion of individuals or the abundance of the ith species expressed as a proportion of total abundance; ln = log base n In addition, species richness index was also calculated using the Margalef’s Index (Margalef 1958), to determine species richness of the community, which is mainly based on the number of species occurring in the particular community as follows: s −1 D = ; where D = Margalef’s Index; s = total species number; and N = total log N number of individuals.

Estimation of Tree Biomass

In this study, total tree biomass was estimated using equations introduced by Istomo (2006) who developed the equations from a study at peat swamp forests in Sumatera, Indonesia. The equations used are as follows: Biomass (above-ground) = 0.0145 (dbh 3) - 0.4659 (dbh 2) + 30.64 (dbh) - 263.32 Biomass (below-ground) = 20.1% of Biomass (above-ground) Total biomass = Biomass (above-ground) + Biomass (below-ground)

RESULTS AND DISCUSSION

Taxonomic Composition

A total of 557 trees of 10 cm dbh and above were enumerated in the plot at Compartment 156 which comprised of 68 species in 49 genera and 26 families (Appendix 1). Four families, i.e. Annonaceae, Guttiferae, Burseraceae and Myrtaceae were the most speciose families in which all of them were represented by six species (Table 1). The first two families contained three genera whilst the third and fourth family, i.e. Burseraceae and Myrtaceae were composed of two genera and one , respectively. Meanwhile, the study plot in Compartment 200 recorded a composition of 100 tree species in 76 genera and 37 families from 555 enumerated trees. The most speciose family was indicated by the Lauraceae and Myrtaceae that were represented by eight species, of which the former contained four genera whilst the latter had only one genus. As a comparison, Khali Aziz et al. (2007) revealed a composition of 67 tree species in 49 genera from 26 families. It is apparent that their findings were very similar to the results from this study at Compartment 156, and prior to their survey, Grippin (2005) conducted a post-felling inventory in a large area of Pekan FR that covered an area of 2,156 ha, where he reported 67 tree species occurring in the surveyed area. Nevertheless, Compartment 200 that was located near the Sungai Bebar, showed a higher species number compared to the Compartment 156 and reports of Khali-Aziz et al. (2007) and Grippin (2005). Preliminary survey on tree communities along the Sungai Bebar by Nizam et al. (2005) also highlighted a high number of tree species with a composition of 113 species in 66 genera from 35 families. Appanah (1997) reported as many as 84 tree species in their study at forested areas of Sungai Bebar. The high species number from this study in this 120 THE MALAYSIAN FORESTER compartment might be due to the difference in soil properties between compartments. Adzmi and Suhaimi (2005) stated that the peat swamp forests of the Sungai Bebar area was not purely of characteristics of a peat swamp forest. They concluded that the Sungai Bebar contributed significant influence to this factor, whereby the river deposited mineral soils along the river, which allows more species to occupy the area. Moreover, Che Aziz and Kamal (2005) mentioned that the Sungai Bebar area was very poor in peat development, and thus resulting of less characteristics of a peat swamp area.

Table 1. Ten leading families with the highest number of species in both compartments at Pekan FR.

Compartment 156 Compartment 200 Family No. of No. of No. of Family No. of No. of No. of species genus stands species genus stands Annonaceae 6 3 46 Lauraceae 8 4 32 Guttiferae 6 3 42 Myrtaceae 8 1 41 Burseraceae 6 2 47 Euphorbiaceae 7 6 66 Myrtaceae 6 1 43 Guttiferae 7 2 42 Lauraceae 5 3 20 Burseraceae 6 2 67 Myristicaceae 5 4 71 Leguminosae 5 5 19 Euphorbiaceae 4 4 94 Anacardiaceae 5 5 12 Leguminosae 4 4 12 Myristicaceae 5 4 37 Rosaceae 3 2 7 Annonaceae 5 2 20 Ebenaceae 3 1 14 Rubiaceae 4 4 6

Table 2. Abundance parameters of trees according to diameter classes in plots at Compartment 156 (C156) and Compartment 200 (C200), Pekan FR.

Diameter Density (stem/ha) Basal area (m 2/ha) Volume (m 3/ha) Class (cm) C156 C200 C156 C200 C156 C200

10.0-24.9 358 425 7.56 7.84 40.79 45.25 (64.3%) (76.6%) (22.6%) (29.5%) (14.0%) (17.0%) 25.0-39.9 138 84 10.36 6.15 80.68 55.84 (24.8%) (15.1%) (31.0%) (23.2%) (27.8%) (21.0%) 40.0-54.9 41 32 7.27 5.30 74.29 68.57 (7.4%) (5.8%) (21.7%) (20.0%) (25.6%) (25.8%) 55.0-69.9 14 5 3.91 1.52 41.28 15.13 (2.5%) (0.9%) (11.7%) (5.7%) (14.2%) (5.7%) >70.0 6 9 4.34 5.73 53.29 80.75 (1.1%) (1.6%) (13.0%) (21.6%) (18.4%) (30.4%)

Total 557 555 33.44 26.54 290.33 265.54 (100%) (100%) (100%) (100%) (100%) (100%)

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Abundance and Tree Distribution

Abundance parameters such as density and basal area are important parameters to describe the forest structure. The density and distribution of tree diameter classes contribute to the structural pattern characteristics of rain forests. Table 2 shows stand structure of trees by diameter classes in Compartment 156 and Compartment 200. It is obvious that the forest stand of the former compartment was dominated by trees with diameter class of 10.0-24.9 cm that were represented by 358 stems per hectare (64.3%). Large trees with diameter of more than 55.0 cm consisted of 20 stands (3.6%), in which the largest tree was Litsea resinosa (Lauraceae) with diameter of 118.4 cm, followed by Koompassia malaccensis (Leguminosae) of 95.0 cm dbh. As for basal area and tree volume, trees with the diameter class of 25.0- 39.9 cm indicated the highest basal area and volume with values of 10.36 m 2 (31.0%) and 80.68 m 3 (27.8%), respectively. In Compartment 200, a similar pattern was observed in which small trees of 10.0 – 24.9 cm dbh dominated the forest stands with a total of 425 stems (76.6%). The common pattern of stand structure in both compartments is of typical stand structure in various forest types where the number of trees declined as the diameter class increased (Appanah & Weinland 1993; Kochummen et al. 1990). In Compartment 200, the largest tree was indicated by K. malaccensis with diameter of 140.0 cm. The tree basal area was the highest for trees with diameter class of 10.0- 24.9 cm of 7.84 m 2 (29.5%). Nevertheless, large trees of more than 70 cm diameter constitute the highest volume of 80.75 m 3 (30.4%) followed by trees of 40.0-54.9 cm diameter class with volume of 68.57 m 3 (25.8%).

Table 3. Abundance parameters for 10 important species in Compartment 156, Pekan FR, that are ranked based on descending order of its Importance Value Index ( IV i).

Total Density Basal area biomass IV i Species (trees/ha) (m 2/ha) (t/ha) (%) Stemonurus secundiflorus 66 1.22 11.26 7.22 Gymnacranthera farquhariana var. eugeniifolia 51 2.08 21.70 7.08 Blumeodendron tokbrai 36 1.80 19.09 5.72 Neoscortechinia forbesii 32 0.92 9.43 4.33 Syzygium napiforme 24 1.48 16.15 4.22 Calophyllum ferrugineum var ferrugineum 18 1.73 19.49 3.92 Litsea grandis 10 1.88 25.84 3.40 Santiria laevigata 17 0.96 10.25 3.00 Durio carinatus 7 1.94 30.30 2.90 Polyalthia hypoleuca 20 0.75 7.73 2.88

From the total of 557 trees censused in the one-hectare plot at Compartment 156, the Euphorbiaceae indicated the highest density with a total number of individuals of 94 stands/ha (16.9%), followed by the Myristicaceae with a density of 71 stands/ha (12.7%) (Table 1). As for Compartment 200, Bursearceae and Euphorbiaceae were amongst families of the highest density of 67 stands/ha (12.1%) and 66 stands/ha (11.9%), respectively. Species-wise, Stemonurus secundiflorus (Icacinaceae) shows the highest density of 66 stands/ha in plot at Compartment 156, whilst the second and third highest density were indicated by Gymnacranthera 122 THE MALAYSIAN FORESTER farquhariana var . eugeniifolia (Myristicaceae) and Blumeodendron tokbrai (Euphorbiaceae) with densities of 51 stands/ha and 36 stands/ha, respectively (Table 3). Subsequently, the plot in Compartment 200 showed Santiria laevigata (Burseraceae) as the species with the highest density represented by 37 stands/ha, followed by Madhuca motleyana (Sapotaceae) and Garcinia negrolineata (Guttiferae) with densities of 30 stands/ha and 27 stands/ha respectively (Table 4).

Table 4. Abundance parameters for 10 important species that are ranked based on its Importance Value Index ( IV i) in Compartment 200, Pekan FR.

Total Density Basal area biomass IV i Species (trees/ha) (m 2/ha) (t/ha) (%) Madhuca motleyana 30 2.24 24.96 5.88 Santiria laevigata 37 1.67 18.88 5.58 Garcinia negrolineata 27 0.71 6.98 3.54 Koompassia malaccensis 3 2.37 57.38 3.40 Durio carinatus 13 0.91 10.16 2.87 Barringtonia conoidea 20 0.41 3.87 2.74 Pimelodendron griffithianum 14 0.66 6.93 2.70 Santiria rubiginosa 15 0.76 7.93 2.64 Syzygium napiforme 12 0.95 11.55 2.62 Shorea platycarpa 7 1.27 18.74 2.57

Table 5. Basal area and total biomass of ten leading families in both study compartments at Pekan FR. (Families are ranked based on descending order of its basal area).

Compartment 156 Compartment 200 Basal Total Basal Total Area Biomass Area Biomass (m 2/ha) (t/ha) (m 2/ha (t/ha) Family Family )

Euphorbiaceae 3.60 37.68 Leguminosae 3.18 65.96 Myristicaceae 3.40 33.74 Burseraceae 2.92 31.92 Guttiferae 3.34 38.52 Sapotaceae 2.25 25.00 Lauraceae 3.28 53.98 Euphobiaceae 1.84 17.82 Myrtaceae 2.59 28.34 Myristicaceae 1.77 18.91 Annonaceae 2.52 27.13 Myrtaceae 1.65 18.29 Bombaceae 2.00 30.93 Dipterocarpaceae 1.54 21.30 Burseraceae 1.94 20.17 Guttiferae 1.20 11.90 Leguminosae 1.49 21.47 Lauraceae 1.09 11.06 Thymelaeaceae 1.22 17.45 Sapindaceae 1.09 14.30

Basal area for all trees in the study plots were estimated at 33.44 m 2/ha and 26.54 m 2/ha in plots at Compartment 156 and Compartment 200, respectively (Table 2). The Euphorbiaceae dominated the basal area of Compartment 156 with a total area of 3.60 m 2/ha (10.7%), followed by the Myristicaceae and Guttiferae with basal areas of 3.40 m 2/ha (10.1%) and 3.34 m 2/ha (9.9%), respectively (Table 5). As for Compartment 200, the Leguminosae showed the highest basal area of 3.18 m 2/ha 123 P. Ismail et al.

(12.0%), whilst Burseraceae and Sapotaceae were the second and third highest in basal areas of 2.92 m 2/ha (11.0%) and 2.25 m 2/ha (8.5%), respectively. At species level, G. farquhariana var . eugeniifolia had the largest basal area of 2.08 m 2/ha in Compartment 156 (Table 3), whilst in Compartment 200, the Koompassia malaccensis indicated the largest basal area of 2.37 m 2/ha (Table 4). Comparing the basal area of trees from this study with other studies in various forest ecosystems in Malaysia, it is apparent that the results at Pekan FR are of similar to those other forest habitats reported by Laidlaw (1994) at Jengka FR (33 m 2/ha), Bukit Tarek VJR (28.82 m 2/ha) and Paya Pasir VJR (33.02 m 2/ha). Nizam et al. (2006) reported an extremely high value of tree basal area of 64.28 m 2/ha at Lesong Virgin Jungle Reserve, Pahang.

1 0 0

8 0

6 0 (m)

4 0

2 0

0 0 20 40 60 80 100 (m )

Figure 3. Random distribution of trees of >10 cm dbh in the one-ha plot at Compartment 156, Pekan FR.

1 0 0

8 0

6 0

(m) 4 0

2 0

0 0 20 40( m ) 60 80 100

Figure 4. Random distribution of trees of >10 cm dbh in the one-ha plot at Compartment 200, Pekan FR.

124 THE MALAYSIAN FORESTER

The distribution pattern of trees in the plots of Compartment 156 and Compartment 200 are shown in Figures 3 and 4, respectively. Based on Morisita’s Index ( Id) of Dispersion, the plot in the Compartment 156 indicated Id = 1.06, whilst Compartment 200 showed an Id = 1.00. The Morisita’s Index stated that Id = 1 reflects a random distribution, while Id = 0 and Id = n indicate uniform and clumped distribution, respectively (Brower et al. 1997). The Id values calculated from this study showed that trees in both plots at Compartments 156 and 200 were distributed randomly. The random distribution patterns of tree communities were also observed in various forest types in Peninsular Malaysia by Raffae (2003) and Nizam et al. (2008). It is well established that the distribution of vegetation communities is influenced by the environmental factors. Ashton (1976) observed floristic variation and distribution of trees in Pasoh were consistently correlated with environmental factors, among which physiography was clearly important. Furthermore, Manokaran et al. (1992) stated that distribution of tree species in Pasoh was partly influenced by the soil properties, location of parent trees and the canopy cover.

Species Importance Values Index (IV i) and Diversity

Species dominance in both study plots were determined by calculating its species importance value index ( IV i). Ten most dominant species based on the highest IV i of both compartments are shown in the preceding Tables 3 and 4. The most dominant species based on the highest IV i in the plot at Compartment 156 was Stemonurus secundiflorus (Sampul Keris) with an IV i of 7.22%, followed by Gymnacranthera farquhariana (Penarahan) and Blumeodendron tokbrai (Gaham Badak) with index values of 7.08% and 5.72%, respectively. It is apparent that although the compartment was classified as Kempas-Ramin-Durian subtype (Blackett & Wollesen 2005), however, those species of K. malaccensis (kempas), G. bancanus (ramin) and D. carinatus (durian) indicated low IV i values of only 0.86%, 1.98% and 2.90%, respectively. The reason to this is because the classification by Blackett and Wollesen (2005) used only the basal area parameter to describe dominance whereas the IV i includes various abundance parameters of relative density, relative frequency and relative dominance (basal area). Hence, dominant species from the results of this study did not follow the classified subtype in which different species, i.e. Sampul Keris-Penarahan-Gaham Badak, seem to dominate the study plot in Compartment 156. Meanwhile, in Compartment 200, the ten most dominant species based on the highest IV i is shown in Table 4. The most dominant species was Madhuca motleyana (Nyatoh ketiau) with IV i of 5.88%, followed by Santiria laevigata (Kedondong kerantai licin, IV i = 5.58%) and Garcinia negrolineata (Kandis, IV i = 3.54%). It was also noted that the D. carinatus (durian) seemed to be the fifth dominant species with IV i of 2.87%. These results clearly indicate Nyatoh and Durian trees were important in the study plot and tallied with the classification of Durian-Nyatoh subtype by Blackett and Wollesen (2005). In addition, the most dominant species in both compartments did not show absolute dominance of the communities. Curtis and Macintosh (1951) stated that species with IV i of more than 10% can be considered as having absolute dominance in a particular community. Diversity of tree species in the forest subtypes using the Shannon-Weiner diversity index ( H’ ) showed values of 3.61 ( H’ max = 4.25) and 4.12 ( H’ max = 4.63) for Compartment 156 and Compartment 200, respectively (Table 6). The diversity of tree species in the Compartment 200 was significantly higher than Compartment 156 at p<0.05. As suggested by Magurran (1988) that the Shannon Index value consists of measurements of two components, i.e. species richness and relative abundance (evenness or unevenness), it is apparent that lower species richness of

125 P. Ismail et al.

Compartment 156 contributed to the lower diversity of tree species in the study plot. This is shown by the Margalef’s Index for species richness whereby the index for Compartment 156 is 24.8, far lower than index value of Compartment 200 of 36.1 (Table 6). Nevertheless, both forest subtypes illustrate high evenness of the tree community with values approaching one ( E = H’/ H’max ). Several similar studies had been conducted in other forest types such as those of Norziana (2003) at the National Park, , Fakhrul-Hatta (2004) at the Krau Wildlife Reserve, Pahang and Saiful (2002) at Ulu Muda Forest Reserve, whereby those studies reported Shannon’s diversity values of more than 4.90. Different forest types contain different species diversity, thus management actions should take into consideration the different characteristics of these forests

Table 6. Summary of various indices of tree communities in the study plots.

Plot Compartment 156 Compartment 200 Shannon-Weiner Index ( H’ ) 3.61 4.12 Margalef’s Index 24.8 36.1 Evenness 0.85 0.89 H’ max 4.25 4.63

Tree Biomass

Total tree biomass at Compartment 156 was estimated at 399.21 t/ha, which was contributed by the above ground biomass (AGB) and below ground biomass (BGB) of 332.40 t/ha and 66.81 t/ha, respectively (Table 7). At Compartment 200, the total biomass of trees was relatively lower than the Compartment 156, estimated at 328.14 t/ha where the AGB was of 273.23 t/ha whilst the BGB was of 54.91 t/ha. Table 7 shows that medium-sized trees of diameter class 25.0-39.9 cm contributed the highest total biomass in the compartment 156 with an estimation of 111.30 t/ha (27.9%). However, in Compartment 200 large trees with diameter greater than 70.0 cm gave the highest biomass of 110.62 t/ha (33.7%). At family level, Lauraceae gave the highest biomass in Compartment 156 with a total value of 53.98 t/ha (13.52%), followed by Guttiferae and Euphorbiaceae with 38.52 t/ha (9.65%) and 37.68 t/ha (9.44%), respectively (Table 5). In Compartment 200, the largest biomass was shown by Leguminosae with a total biomass of 65.96 t/ha (20.10%). The second and the third largest biomass were represented by the Burseraceae and Sapotaceae, of which the former had total biomass estimated at 31.92 t/ha (9.73%) whilst the latter showed biomass estimation of 25.00 t/ha (7.62%). Species-wise, Durio carinatus gave the highest tree biomass in Compartment 156 estimated at 30.30 t/ha, and subsequent highest biomass was represented by Litsea grandis of 25.84 t/ha (Table 3). The legumes gave the highest biomass at family level in Compartment 200 with Koompassia malaccensis contributing the highest biomass with an estimation of 57.38 t/ha. The nyatoh trees ( Madhuca motleyana ) gave biomass far lower than the legume with an estimated value of 24.96 t/ha. As a comparison with another study in a peat swamp forest in Sumatera. Istomo (2006) estimated total tree biomass of 280.12 t/ha, which was relatively lower than total tree biomass gathered from this study. The amount of tree biomass in Peninsular Malaysia depends on the forest types where the studies were conducted. These reported studies used allometric equations derived by Kato et al. (1978) to estimate tree biomass in their study areas. For instance, Raffae (2003) 126 THE MALAYSIAN FORESTER

Table 7. Tree biomass (t/ha) of various diameter classes in plots at Compartment 156 and Compartment 200, Pekan FR.

Diameter Compartment 156 Compartment 200 class (cm) AGB BGB Total AGB BGB Total (t/ha) (t/ha) (t/ha) (t/ha) (t/ha) (t/ha)

10.0-24.9 61.78 12.42 74.20 60.72 12.20 72.92 25.0-39.9 92.67 18.63 111.30 53.21 10.70 63.91 40.0-54.9 69.76 14.02 83.78 50.37 10.12 60.49 55.0-69.9 41.71 8.38 50.09 16.82 3.38 20.20 >70.0 66.48 13.36 79.84 92.11 18.51 110.62 Total 332.40 66.81 399.21 273.23 54.91 328.14 reported total above ground biomass of an island forest in to be about 529 t/ha. Mat-Salleh et al. (2003) who conducted a similar study at a beach forest in Cape Rachado, estimated the total above ground biomass of trees at 233.4 t/ha. The biomass of a montane forest in Fraser’s Hill was estimated at 218.7 t/ha Petol (1994). It should be noted that these studies enumerated trees of 5 cm diameter and above, while the current study measured trees greater than 10 cm; thus the values obtained may be underestimated.

ACKNOWLEDGEMENTS

The authors would like to express their sincere gratitude to the Forestry Department of Pahang for providing the study site and assistance, and also to staffs of Natural Forest Programme, Forestry Research Institute Malaysia for assisting in data collection.

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Appendix 1. List of tree species in Compartment 156 and Compartment 200, Pekan FR.

Compt. Compt. No Species Family 156 200 1 Acer laurinum Hassk. Aceraceae + + 2 Adenanthera sp. Kosterm. Leguminosae + - 3 Aidia densiflora (Wall.) Masam Rubiaceae - + 4 Alangium nobile (C.B. Clarke) Harms Alangiaceae + + 5 Aporosa lunata (Miq.) Kurz Euphorbiaceae - + 6 Archidendron clyperia (Jack) I.C. Nielsen Leguminosae - + 7 Artocarpus integer (Thunb.) Merr. Corner Moraceae + + 8 Artocarpus kemando Miq. Moraceae - + 9 Austrobuxus nitidus Airy Shaw Euphorbiaceae - - 10 Baccaurea bracteata Müll.Arg. Euphorbiaceae - + 11 Barringtonia conoidea Griff. Lecythidaceae - + 12 Beilschmiedia glabra Kosterm. Lauraceae + + 13 Beilschmiedia kunstleri Gamble Lauraceae - + 14 Bhesa paniculata Arn. Celastraceae + + 15 Blumeodendron tokbrai (Blume) J.J.Sm. Euphorbiaceae + + 16 Bouea macrophylla Griff. Anacardiaceae - + 17 Brackenridgea palustris Bartell. Ochnaceae + - 18 Callerya atropurpurea (Wall.) Schot Leguminosae - + 19 Calophyllum ferrugineum var ferrugineum Guttiferae + + Ridl. 20 Calophyllum sclerophyllum Vesque Guttiferae + - 21 Calophyllum soulattri Burm.f. Guttiferae - + 22 Campnosperma auriculatum (Blume) Anacardiaceae - + Hook.f. 23 Carallia brachiata (Lour.) Merr. Rhizophoraceae + - 24 Cerbera manghas L. Apocynaceae - + 25 Cinnamomum altissimum Kosterm. Lauraceae - + 26 Cratoxylum arborescens (Vahl) Blume Guttiferae + - 27 Cryptocarya impressa Miq. Lauraceae + + 28 Cryptocarya kurzii Hook.f. Lauraceae - + 29 Ctenolophon parvifolius Oliv. Linaceae + + 30 Dacryodes longifolia (King) H.J. Lam Burseraceae - + 31 Dacryodes macrocarpa (King) H.J. Lam Burseraceae + + 32 Dacryodes rostrata (Blume) H.J. Lam Burseraceae - + 33 Dendrokingstonia nervosa (Hook.f. & Annonaceae + - Thomson) Rauschert 34 Dialium indum var indum L. Leguminosae + + 35 Dillenia pulchella (Jack) Gilg Dilleniaceae - + 36 Diospyros foxworthyi Bakh. Ebenaceae + - 37 Diospyros lanceifolia Roxb. Ebenaceae - + 38 Diospyros maingayi (Hiern) Bakh. Ebenaceae + +

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Appendix 1. Continued

Compt. Compt. No Species Family 156 200 39 Diospyros siamang Bakh. Ebenaceae + + 40 Diplospora malaccensis Hook.f. Rubiaceae - + 41 Durio carinatus Mast. Bombacaceae + + 42 Elaeocarpus floribundus Blume Elaeocarpaceae + + 43 Engelhardtia serrata Blume Juglandaceae - + 44 Garcinia bancana var bancana (Miq.) Miq. Guttiferae + - 45 Garcinia eugeniifolia Wall. ex T. Anderson Guttiferae - + 46 Garcinia negrolineata Planch. ex T. Guttiferae + + Anderson 47 Garcinia parvifolia (Miq.) Miq. Guttiferae - + 48 Garcinia rostrata (Hassk.) Miq. Guttiferae + + 49 Gonystylus bancanus (Miq.) Kurz Thymelaeceae + + 50 Gordonia maingayi Dyer Theaceae - + 51 Gymnacranthera farquhariana var. Myristicaceae + + eugeniifolia (Hook.f. & Thomson) Warb. 52 Hopea mengerawan Miq. Dipterocarpaceae - + 53 Horsfieldia crassifolia (Hook.f. & Myristicaceae + + Thomson) Warb. 54 Ilex cymosa Blume Aquifoliaceae - + 55 Knema conferta (King) Warb. Myristicaceae + + 56 Koompassia malaccensis Maing. ex Benth. Leguminosae + + 57 Kostermansia malayana Soegeng Bombaceae + - 58 Lithocarpus leptogyne Leguminosae + + 59 Litsea grandis (Wall. ex Nees) Hook.f. Lauraceae + + 60 Litsea resinosa Blume Lauraceae + + 61 Litsea sp . Lauraceae + - 62 Litsea teysmannii Gamble Lauraceae - + 63 Lophopetalum multinervium Ridl. Celastraceae + + 64 Macaranga gigantean (Rchb.f. & Zoll.) Euphorbiaceae - + Müll.Arg. 65 Macaranga pruinosa (Miq.) Müll.Arg. Euphobiaceae + + 66 Maclurodendron porteri (Hook.f.) T.G. Rutaceae + - Hartley 67 Madhuca motleyana (de Vriese) J.F. Sapotaceae + + Macbr. 68 Mangifera griffithii Hook.f. Anacardiaceae - + 69 Memecylon paniculatum Jack Melastomataceae - + 70 Myrica esculantha Buch.-Ham Myristicaceae - + 71 Myristica gigantea King Myristicaceae + - 72 Myristica lowiana King Myristicaceae + + 73 Nageia motleyi (Parl.) de Laub. Coniferae - + 74 Neoscortechinia forbesii (Merr.) Welzen Euphorbiaceae + + 75 Nephelium maingayi Hiern Sapindaceae + + 76 Parastemom urophyllus (Wall. ex A. DC.) Rosaceae + + A. DC. 77 Parishia sp. Anacardiaceae - + 78 Pentace adenophora Kosterm. Tiliaceae - +

131 P. Ismail et al.

Appendix 1. Continued

Compt. Compt. No Species Family 156 200 79 Pimelodendron griffithianum (Müll.Arg.) Euphorbiaceae - + Benth. 80 Polyalthia glauca (Hassk.) F. Muell. Annonaceae + + 81 Polyalthia hypoleuca Hook.f. & Thomson Annonaceae + + 82 Polyalthia laterifolia (Blume) King Annonaceae + - 83 Polyalthia sclerophylla Hook.f. & Annonaceae - + Thomson 84 Pometia pinnata J.R. Forst. & G. Forst Sapindaceae + + 85 Pouteria maingayi (C.B. Clarke) Baehni Sapotaceae + - 86 Prunus grisea (Blume) Kalkman Rosaceae + + 87 Psydrax sp. Rubiaceae + + 88 Pternandra coerulescens Jack Melastomataceae - + 89 Quassia indica (Gaertn.) Noot. Simaroubaceae + + 90 Sandoricum beccarianum Baill. Meliaceae + - 91 Santiria apiculata Benn. Burseraceae + - 92 Santiria laevigata Blume Burseraceae + + 93 Santiria oblongifolia Blume Burseraceae + - 94 Santiria rubiginosa Blume Burseraceae + + 95 Santiria tomentosa Blume Burseraceae + + 96 Scaphium longiflorum Ridl. Sterculiaceae - + 97 Semecarpus rufovelutinus Ridl. Anacardiaceae - + 98 Shorea platycarpa F. Heim Dipterocarpaceae + + 99 Stemonurus secundiflorus Blume Icacinaceae + + 100 Syzygium cerinum (M.R. Hend.) I.M. Myrtaceae + + Turner 101 Syzygium gracile (Korth.) Amsh. Myrtaceae - + 102 Syzygium griffithii (Duthie) Merr. & L.M. Myrtaceae - + Perry 103 Syzygium inophyllum (DC.) Roxb. Myrtaceae + + 104 Syzygium kiahii var kiahii (M.R. Hend.) Myrtaceae + + I.M. Turner 105 Syzygium kunstleri (King) Bahadur & R.C. Myrtaceae - + Gaur 106 Syzygium napiforme (Koord. & Valeton) Myrtaceae + + Merr. & L.M. Perry 107 Syzygium pseudocrenulatum (M.R. Hend.) Myrtaceae + - I.M. Turner 108 Syzygium sp . Myrtaceae + + 109 Trigoniastrum hypoleucum Miq. Trigoniaceae - + 110 Urophyllum glabrum Wall. Rubiaceae - + 111 Vatica pauciflora (Korth.) Blume Dipterocarpaceae - + 112 Xanthophyllum ellipticum Korth. ex Miq. Polygalaceae - + 113 Xanthophyllum rufum Benn. Polygalaceae - + 114 Xantophylum amoenum Chodat Polygalaceae - + 115 Xantophylum griffithii Hook.f. ex A.W. Polygalaceae - + Benn. 116 Xylopia caudata Hook.f. & Thomson Annonaceae - +

132 THE MALAYSIAN FORESTER

Appendix 1. Continued

Compt. Compt. No Species Family 156 200 117 Xylopia fusca Maingay ex Hook.f. & Annonaceae + + Thomson 118 Xylopia malayana Hook.f. & Thomson Annonaceae + - No. of species: 68 100 Note: + = present - = not present

133