Decomposition of tissue baits and termite density along a gradient of human land-use intensification in Western Kenya.

Termites are important decomposers and 'ecosystem engineers' in tropical ecosystems. Furthermore, termite assemblages are sensitive to human land-use intensification and often termite density and the importance of soil-feeding termites decrease with land-use intensification. These changes in termite assemblages may also lead to a decrease in termite-mediated ecosystem processes (e.g. soil formation, cellulose decomposition). We compared density and functional composition of termites with cellulose removal from undisturbed primary forests to farmlands (Kakamega Forest, Western Kenya). In contrast to the expectation, we found no response of termite abundance along the gradient of land-use intensification. However, as expected, the relative abundance of soil-feeders decreased from primary forests to farmlands. In contrast, frequency of attack on tissue paper baits and removal of tissue showed a clear hump-shaped relationship to land-use intensification with high values in secondary forests. These nonconcordant patterns of density and functional composition of termite assemblages with cellulose removal by termites suggest that it may be misleading to infer changes in a process by the characteristics of the assemblage of organisms that mediate that process. [ABSTRACT FROM AUTHOR]