Rehabilitation of Tropical Rainforest Ecosystems

Rehabilitation of Tropical Rainforest Ecosystems 24- 25 October 2011, Kuala Lumpur

RICHNESS OF SAPLINGS AT DIFFERENT ALTITUDES IN HUTAN LIPUR SG. TUA, SELANGOR, MALAYSIA Norfazlina Mohd Nawi1,2,* and Faezah Pardi1 1

Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Malaysia 2 Centre for Biodiversity and Sustainable Development, Universiti Teknologi MARA, 40450 Shah Alam, Malaysia *Corresponding author: [email protected]

Summary: This study was conducted to examine the richness of sapling plant species at Hutan Lipur Sg. Tua, Selangor, Malaysia and to determine the effects of altitude on the distribution and abundance of sapling plant species. This research was conducted in a 400 m² plot (each) at the altitudes of 265 and 452 m above sea level (a.s.l). The field survey resulted in a total of 376 individuals comprising 43 genera and 48 species. The richness of sapling plant species at 265 m altitude was 3.0841, which was higher than 452 m altitude (3.0557). There was no significant difference in species richness between the two elevations. In terms of species similarity, only 20.8% of species occur in both elevations which might be due to small variation in species diversity in these locations. Keywords: Richness, saplings, altitudes

INTRODUCTION While the tropical rain forests cover only 6.4% of the Earth’s terrestrial surface, they maintain a large proportion of the world’s biotic diversity (Thomas, 2003). They are highly dynamic and responsive ecosystems. Their physical structure and processes may remain relatively stable over time, but species composition is thought to constantly fluctuate around quasi-equilibrium or change slowly in the long-term. A lot of efforts have been put in to understand the changes in plant species richness with altitudes. The richness, which relates to environmental factors, p r o mp t e d t h i s study that aims a t looking at the diversity of sapling plant species as affected by different altitudes. The environmental factors that characterize the altitude include light transmittance, air, relative humidity and soil types. Besides, i t is also affected by the competition and enrichment from regional species pool. This study also examined soil types and their properties at different altitudes that may affect the richness of sapling plant species.

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Therefore, this study was conducted with two objectives: (i) to determine the richness of sapling plant species at Hutan Lipur Sg. Tua, Selangor, and (ii) to determine the effects o f altit ude s to t he distribution and abundance of sapling plant species.

MATERIALS AND METHODS The study was conducted at Hutan Lipur Sg. Tua, near Ulu Yam, Selangor. The forest is located within the Selangor State Park in the district of Gombak, and is administrated by the Selangor Forestry Department. Sg. Tua forest is characterized by permanent temperature ranging from 20 oC at night and 35oC in the day with a high relative humidity (above 80%). Topography of Sg. Tua forest consists mainly of lowland, undulating and riverine areas and gently rolling hills with slopes. The overall vegetation type in Sg. Tua is lowland dipterocarp forests in characterized by high proportion of species in the family of Dipterocarpaceae. Tree sapling specimen collections were made at two locations at different altitudes. The first sampling was conducted at 265 m above sea level (a.s.l) and the second was at 452 m a.s.l. A GPS receiver was used to determine the topographic elevation of the selected study sites. A sampling was conducted based on quadrat sampling. For this purpose, a quadrat measuring 20 m × 20 m was established in each location. The quadrat was gridded into four sub-plots, each 10 m × 10 m in size. All tree saplings with a diameter at breast height (DBH, 1.3 m above the ground) ≤ 5 cm and height ≥ 10 cm were measured, tagged and identified by species. The DBH was measured using a DBH tape. At the centre of each subplot, soil samples were taken from 0 to 15 cm depth using soil auger. If field identification was not possible, the botanical specimens were taken to the herbarium section of the Forest Research Institute Malaysia (FRIM) for identification. As stated by Magurran (1988), methods for measuring species diversity within the sa mple or co mmunity consist of two components, namely species richness and relative abundance (evenness and unevenness). In this study, species diversity was determined using the Shannon-Weiner Diversity Index (H’) (Shannon and Weaver, 1949). This method assumes that all individuals were randomly sampled from indefinitely large population and all species are represented in the sample (Magurran, 1988). Shannon-Weiner diversity index and evenness were calculated using the following equations, respectively:

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Species diversify ( Where H’= Shannon-Wiener diversity index pi= proportion of individuals belonging to species i ln= natural log (i.e., 2.718) Evenness (E) = H´/ln S Where H’ = Shannon-Weiner diversity index S = number of species H’max = ln S Similarity index measures the degree to which the species composition of two quadrats or samples matches is alike (Kent and Coker, 1992). The basis is that two sites are more similar if they share more species and they are more dissimilar if there are more species unique for one both (Van Tongeren, 1987). In this study, the Sörensons coefficient was used to determine the similarity between plots as follows: Sörensons coefficient (S) = Where: a = number of species common to plots A and B b = number of species occurring in plot A c = number of species occurring in plot B

RESULTS AND DISCUSSION Taxonomic Composition The two quadrats established at Hutan Lipur Sg. Tua yielded a total of 376 individuals from 43 genera and 48 species of trees ≤ 5 cm DBH. Table 1 shows a summary of taxonomic composition for two elevations. The numbers of genera, species and individuals recorded from the 265 m a.s.l quadrats were 23, 25 and 171, respectively. Slightly lower numbers of genera and species were recorded in the 452 m a.s.l. plots which were 20 and 23, respectively. However, at this elevation, higher number of individuals (205 trees) was recorded. Table 1: A summary of results from field survey Elevation (m) 265 452

No. of Genera 23 20

No. of Species 25 23

No. of individuals 171 205

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The four dominant species in quadrats were Amischotolype sp., Lasianthus sp. (both with 17 individuals present) followed by Rinorea sp. and Syngramma alysmifolia (16 and 15 individuals, respectively). Five species were identified as less dominance included Ficus obseura with 4 individuals present, followed by 4 species that only had 3 individuals which included Alstonia angustiloba, Melineria latifolia, Helicia sp. and Ficus glossulariodes. Species become dominant in the plots when they are able to survive and can tolerate with the physical characteristic of habitats that influence the species composition. Species Richness and Evenness at Different Altitudes The richness of sapling plant species at altitude 265 m was 3.0841. This richness was slightly less than that of 452 m altitude (3.0557) (Table 2). This translates into a decreasing trend in sapling plants at the rate of 0.92% from the lower to higher elevations studied. A c c o r d i n g t o P o u l o s e t a l . ( 2 0 0 7 ) , t he diversity and richness of species does not only depend on elevation but it is also influenced by soil type, soil moisture, pH, temperature of the environment. The soil pH at 265 m elevation was slightly higher compared to that at 452 m (4.2 and 4.6). This might explain the slight difference in species richness between the two elevations. Based on the number of species recorded, 4.26% more species were found at 265 m altitude than at 452 m. However, the number of individual sapling plants was 9.04% higher at 452 m altitude. This s u g g e s t s that species diversity declined at the altitude of 452 m by two species (0.53%). According to Benizri and Amiaud (2005), the level of biodiversity in the above ground is influenced by its interrelationships with the below ground diversity of soil activity. Therefore, the characteristic of soil at the different altitudes could be a factor that influences the composition of species in the habitats. A c c o r d i n g t o Marta et al. (2004), species abundance was higher in the plot with high species richness. In this study, sapling plants distribution in the plot at 452 m altitude was more uniform. From an independent samples t-test analysis, it was found that there was no significant difference in the richness of the two elevations (p=0.4923) and this was because of small differences in altitudes. Table 2: Species richness and evenness in two elevations. Elevation (m) 265 452


Richness 3.0843 3.0557

Evenness 0.958 0.975


Similarity of Species In terms of species similarity, about 20.8% of species were found in both elevations and they were: Calamus sp., Zingiber sp, Clidemia hirta, Amischotolype sp. and Tectaria gemmifera. The low percentage of species similarity in these elevations might be due to a slight difference in species diversity between the two elevations discussed in the earlier section. The probability of observing similarities in species composition in the two sites may increase as the differences in species diversity increases. This is agreeable with Whittaker (1965) who found a little overlap in species composition in the sites. In this study, about 79.2% of the total species composition was found in one elevation i n wh i c h the species ma y h a v e low tolerance and can only adapt to limited environmental factors. CONCLUSION A total of 376 of sapling plants were recorded at the two study sites of Hutan Lipur Sg. Tua which consisted of 43 genera and 48 species. The species richness of sapling plants at 265 m altitude was 3.0841, which was not significantly different (p ≥ 0.05) compared to that of 452 m altitude (3.0557). Only 20.8% of similar species were found in both elevations due to a slight difference in species diversity.

ACKNOWLEDGEMENT The authors would like to thank the Department of Forestry, Selangor for supporting this research. The appreciation also goes to Mohd Nazip Suratman and Kamarudin Saleh for providing expertise in plant identification. REFERENCES Benizri, E. and Amiaud, B. 2005. Relationship between Plants and Soil Microbial Communities in Fertilized Grasslands. Soil Biology & Biochemistry, 2055–2064. Kent, M. and Coker, P. 1992. Vegetation Description and Analysis: A Practical Approach. CRC Press, 156−176. Magurran, A.E. 1988. Ecological Diversity and its Measurement. Princeton University, New Jersey, 125−135. Marta, A.F and Peter, Z.F. 2004. Changes in Forest Vegetation and Arbuscular Mycorrhizae along a Steep Elevation Gradient in Arizona, Forest Ecology and Management, 200, 294–295. Universiti Putra Malaysia – Mitsubishi Corporation

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