Abstract: The relationship between biodiversity and ecosystem functioning has emerged as a major scientific issue today. Concerns over the unprecedented loss of biodiversity have motivated ecologists to conduct considerable research, describing the relationship between biodiversity and ecosystem function, and detecting the mechanisms by which diversity impacts ecosystem functioning. Statistical and biological hypotheses have been proposed to explain the observed relationship between biodiversity and ecosystem functioning. The former, including hypotheses related to sampling and statistical averaging effects, are inclined to view empirical results from a purely statistical perspective, while the latter are built on biological effects of biodiversity, including niche complementarity, positive interactions between species, and insurance effects. This paper presents a review of several representative experimental studies, including. Ecotron, Cedar Creek, microbial microcosm and BIODEPTH, and the associated debates about the interpretation of experimental observations.

Key words: brushtail possum, Trichosurus vulpecula, invasive marsupial, control, biocontrol, New Zealand