Biodiversity and Biogeochemical Cycles

Abstract

Ever-increasing human activity across the tropical landscape inevitably results in the loss of biodiversity at some spatial scales (Wilson 1988; Whitmore and Sayer 1992). For example, it is well known that the replacement of diverse tropical forests with less species-rich systems results in the loss of genetic resources and of new, potentially useful plants and animals. Global-scale changes are also likely to have an impact on biodiversity, both directly through physiological responses to climate change, and indirectly through changes in the physical environment, ecosystem processes, and species interactions (Harte et al. 1992). To better determine the outcome of human-induced changes to tropical forests, we must understand the role of biodiversity in mediating ecosystem-level processes. This chapter examines the relationship between biodiversity and biogeochemical cycles in tropical forests. We begin by defining appropriate terms for biodiversity and biogeochemistry and then build a conceptual framework for linking species and ecosystem processes. Finally, we discuss the empirical evidence documenting the effects of changes in biodiversity on energy processing and nutrient cycling in ecosystems.