Abstract: The relationship between biodiversity and ecosystem stability is a hot subject in ecological science. Focused on this issue, the research history and different academic viewpoints were reviewed, and the achievements in the theoretical and experimental fields as well as the existing problems were elaborated. In terms of theoretical study, the relationship between biodiversity and ecosystem stability is complicated, because the concepts of the two are multifold. In terms of experimental study, the existing research results only emphasize a few types of diversity and ecosystem stability, and rarely uncover the mechanisms resposible for ecosystem stability. In the studies of biodiversity and ecosystem functioning, the important problem is not merely the conclusions, but also the mechanisms hidden behind. A major future challenge is to understand how the biodiversity dynamics, ecosystem processes, and abiotic factors interact.

Key words: Urban soil, Heavy metal, Concentration, Principal component analysis, Nanjing