Forest Structure and Composition of Trees in Two Sympatric Anthropoid Primates

Eurasscience Journals Eurasian Journal of Forest Science (2014) 1(1): 1-14 FOREST STRUCTURE AND COMPOSITION OF TREES IN HABITAT OF PRIMATES IN GHANA Edward D. Wiafe Department of Environmental and Natural Resources Management, Presbyterian University College, P. O. Box 393, Akropong-Akuapem, Ghana. Abstract Tree composition, density and diversity were assessed within a monkey sanctuary that has been tempered with by human beings. The study took place in Buabeng-Fiema monkey Sanctuary in Ghana to document the vegetation structure of the non-human primate habitat. The habitat types were stratified into three classes; as natural forest, mixed forest and cultivated area and 20 plots of dimensions 20m x 25m were established in each of the habitat types. All trees ≥ 10 cm diameter at breast height were identified and measured. In the mean number of trees per hectare was 17.5 (S.D=5.5, N=20), 12.7 (S.D=3.6, N=20) and 7.4 (S.D=7.4, N=20) in the natural forest , mixed forest and cultivated area respectively. The diversity, relative density and relative dominance differed in all the three habitat types. Moreover, the number of trees reduced with increasing height and basal area in all the three habitat types. The variations in the three habitat type provide good resources that may be required by the primates for survival but can promote and deepen human-wildlife conflict. Keywords: Anthropoid monkey, Buabeng-Fiema, habitat types, wildlife sanctuary Özet Bu çalışmada insanlar tarafından açığa çıkarılmış bir maymun korunağı alanında ağaç türü bileşimi, yoğunluğu ve çeşitliliği incelenmiştir. Çalışma Buabeng-Fiema’da (Gana) yer alan ve insansız bir bölge olan primat yaşam alanındaki bitki yapısını ortaya çıkarmak için maymun korunağı alanında yürütülmüştür. Yaşam alanındaki bitki toplumu doğal orman, karışık orman ve suni bitkilendirilmiş alan olarak üç sınıfta incelenmiş olup her bir alandan 20’şer tane 20m x 25m’lik alanlar örneklenmiştir. Göğüs yüksekliği çapı 10cm’den büyük olan bütün bireyler teşhis edilmiş ve ölçülmüştür. Hektardaki ortalama ağaç sayısı doğal orman, karışık orman ve suni bitkilendirilmiş alanda sırasıyla 17.5 (S.D=5.5, N=20), 12.7 (S.D=3.6, N=20) ve 7.4 (S.D=7.4, N=20) olarak tespit edilmiştir. Tür çeşitliliği, bağıl yoğunluk ve bağıl başatlık değerleri bakımından her üç habitat için de farklı sonuçlar elde edilmiştir. Ayrıca her üç habitatta da ağaç sayısı azaldıkça ağaç boyu ve göğüs yüzeyi alanı artmıştır. Habitatlardaki orman kuruluşlarındaki çeşitlilik primatların yaşamı için gerekli kaynakları tatmin edici düzeyde sunmakla birlikte insan-vahşi yaşam çatışmasını tetikleme potansiyeli taşımaktadır. Anahtar kelimeler: İnsansı maymun, Buabeng-Fiema, Habitat türleri, Vahşi yaşam habitatları. INTRODUCTION Non-human primates and trees have been evolved to be involved in a very complex set of interaction (Tutin et al. 1996; Chapman and Chapman 1996). It is apparent that trees offer a lot of services to eurasscience.com primates such as food and cover (Kinnaird 1992; Cowlishaw and Dunbar 2000). In the efforts of extracting these services from the plant community, primates also contribute to the evolution and existence of plants in services like pollination of flowers (Carthew and Goldingay 1997), dispersal of seeds (Chapman 1 Forest Structure and Composition of Trees – Wiafe 1(1): 1-14 (2014) 1989; Chapman and Chapman 1996; Howe 1988) and germination of seeds (Liberman et al. 1979) which tends to play a crucial role in regeneration of tropical forests (Wrangham et al. 1996; Chapman and Onderdonk 1998). Kessler et al. (2005) defines forest community as an association of interacting plant species inhabiting some definite area. Thus, we may have entire plants (as well as shrubs, herbs, etc.) communities interacting in an area in terms of competition, exploitation, and mutualism. According to Kessler et al. (2005), the community structure includes attributes such as number, relative abundance and diversity of tree species. Huang et al. (2003) stated that for an individual forest community, there are many factors which can affect the numbers of species present. Some of the influences on the community are from within the community itself while others including human-induced forest disturbances such as farming and logging are external. Huang et al. (2003) further added that severe or frequent forest disturbances affect the structure and number of plant species in the forest community. When forest community is disturbed, more room is created for natural regeneration to take place. However, if the disturbance becomes too much then the forest becomes too harsh and species diversity may decline. From this, it can be deduced that human induced forest disturbances such as logging and intensive farming alters the dynamics of tree species abundance and diversity. Tropical forests are complex ecosystems (Gibbs et al., 2007) which have not been well understood. The forest that appears to be unchanging climax vegetation passes through elusive changes in floristic composition and structural characteristics as result continuous flux of different species with varying recruitment and mortality rates (Whitmore, 1992) . Therefore, investigations into floristic composition and structure of forests are very useful exercise for providing information on species richness of the plants and the changes that they undergo that can potentially be useful for management purpose and assist in understanding forest ecology and ecosystem functions (Pappoe et al. 2010). However, the documentation on the composition of trees and structure of most of the forests in Ghana for scientific community in general is scant except for those of Vordzogbe et al. (2005), Anning et al. (2008) and Addo-Fordjour et al. (2009); Hall and Swaine (1981) and Pappoe et al. 2010). Though little attention is focused on vegetation monitoring at where the object of management is animal conservation such as national parks, resource reserves and wildlife sanctuary; there is an urgent need eurasscience.com for information on vegetation due to increasing rate of deforestation in tropical areas. There is the need, therefore, for regular survey of the forest to generate information on its compositional and structural attributes to update existing ones and thereby contribute knowledge to the understanding of the forest ecosystem for effective management. The aim of this study was to investigate the characteristics of the trees that play a vital role to the existence of two primate species. The objectives of the study were to determine the species composition of the trees, investigate the trend of size class distribution of the trees and examine the density and diversity of the tree species occurring in different habitat types of the monkey range. This will be used as base-line information for future monitoring of the primates’ vegetation. Study Area The area of study, Buabeng-Fiema Monkey Sanctuary (Figure 1) is located in th (...truncated)