Biodiversity and ecosystem functioning

Abstract This chapter examines the relationship between biodiversity (most often measured as species richness) and the functioning of ecosystems. Examined in detail are the effects of biodiversity on: ecosystem productivity, nutrient use and nutrient retention, community and ecosystem stability, and invasibility by exotic species. A careful look, over two decades, at experimental results and meta-analyses confirms the positive impact of species richness on productivity, ecosystem stability, and nutrient retention. Thus, we can confidently conclude that biodiversity matters to the healthy functioning of ecosystems, although we do not yet know how many species are needed to ensure the successful functioning of any given ecosystem. The chapter concludes with a discussion of six important, but unanswered question in the study of biodiversity and ecosystem functioning.