Edge effects on dung beetles (coleoptera: scarabaeidae) abundance and diversity in Kibale forest.
MetadataShow full item record
Land use change resulting from ill planned human activities and un-sustainable exploitation of resources has gained status as the most important driver of ecosystem degradation. The outcome, conspicuous edges that have permeate impacts on the distribution, survival and persistence of species in forest ecosystems are created. However, there is a disagreement about the existence and intensity of edge effects and also no consensus on how edges affect some organisms including dung beetles in tropical African forests. In this study, I assessed whether edges have an effect on Scarabaeidae abundance and diversity. I tested two other hypotheses relative to edge, remnant shape and microclimate parameters on dung beetle composition: remnant and edge shape have no effect on dung beetle abundance and diversity. And that variations in microclimate parameters (light intensity and soil temperature) have no effect on dung beetle abundance and diversity. Dung beetles were trapped employing dung baited traps in five sampling locations each comprising of an edge and forest interior. Twenty-eight dung beetle taxa represented in fifteen dung beetle genera were trapped. The community was mostly dominated by genus Onthophagus followed by Genus Dichotomius and Catharsius while Oniticellus accounted for the least abundant genera. I observed high species richness at the edges compared to the forest interior of sampled locations. However, species richness was not affected by edges. I also found strong edge effects on diversity and abundance of dung beetles in all sampled locations A (t = 2.7142, p< 0.05), B (t = 3.07, p< 0.05), C (t = 2.38, p< 0.05), D (t = 3.06, p< 0.05) and D (t = 2.97, p< 0.05). I found remnant, edge shape not to have significant effects on dung beetle diversity (t = 1.291, p> 0.05) and the same for species richness (t = 0.1712, p> 0.05). Higher levels of light intensity, and soil temperature was observed in edges than in interior locations. The difference in microclimate parameters between edges and the forest interior was significantly different and this affected species composition. Additionally, similar species were trapped between forest edges and the forest interior. However, a strong statistical difference in species similarity was shown within and between sampled locations (t = 2.279, p< 0.05). With regard to biodiversity investigation, this study demonstrated the effects of edges on dung beetle communities. Because of the continued deterioration of forest habitats resulting into creation of edges, more studies should be carried out to fully understand the impact of anthropogenic disturbances of African invertebrate biodiversity.