A series of concise books, each by one or several authors, will provide prompt, world-wide information on approaches to analyzing ecological systems and their interacting parts. Syntheses of results in turn will illustrate the effectiveness, and the limitations, of current knowledge. This series aims to help overcome the fragmen- tation of our understanding about natural and managed landscapes and water- about man and the many other organisms which depend on these environments. We may sometimes seem complacent that our environment has supported many civilizations fairly well - better in some...