This proposal on "Ecological Engineering: Theory and Development in the U.S. and China" between Dr. William Mitsch and Dr. David L. Johnson of the Ohio State University Research Foundation and Professors Ma Shijun, Yan Jingsong, and Li Dianmo of the Institute of Zoology of the Academia Sinica, is jointly sponsored by NSF and the Chinese Academy of Sciences. This cooperative program will explore and define the concept of ecological engineering. "Ecological engineering" and "ecotechnology" are terms used to indicate the design of human society with its natural environment for the benefit of both. The general approaches to ecological engineering are somewhat different in the U.S. and in China, although the overall concepts are the same. Chinese and American researchers will collaborate to identify underlying concepts and theories (principles) of ecological engineering, including concepts such as self design, multi layering, and resiliency and restoration, and maximum power. Using mathematical models of six research sites in both the U.S. and China, the investigators will attempt preliminary verification of some of these principles.