This award provides support for a two year cooperative project between a group from the Environmental Sciences Division, Oak Ridge National Laboratory led by Dr Donald Deangelis, and a group from Ryukoku University, Japan, led by Professor Ei Teramoto. The objective of the proposed research is to demonstrate how the macroscopic processes of energy and nutrient flow in an ecosystem are related to the spatiotemporal behavior and fate of species populations within that ecosystem. Traditionally, two general theories have been applied to the understanding of ecological food webs, namely the population and community dynamics theory, emphasizing the modelling of population numbers, and the ecosystem process theory, emphasizing the modelling of energy and nutrient flows. There has been relatively little interaction between ecologists employing each of these approaches and this has hindered the development of ecological theory. This project aims at developing theoretical approach to ecological food webs which integrates both approaches. Two specific food webs are to be studied; a termite-microbial- detritus interaction in a subtropical ecosystem, and a periphyton-grazer community in artificial streams. The project will involve the development of models linking ecosystem energy and nutrient flows with population dynamics. This integrated approach, may help clarify several important theoretical questions including the relationships of energy and nutrient supply regimes to the stability and species diversity within an ecosystem, the coevolution of species in relation to structure and processes in food webs, and the causes and effects of spatiotemporal heterogeneity of ecosystems. Both the US and Japanese scientists involved in the project are highly regarded in their fields. The two groups have complementary research interests with similar aims but different orientations, the US group being more oriented towards ecosystem processes, and the Japanese group more towards population/community dynamics. This project should yield new insights into the interplay between the dynamic processes of species populations in an ecosystem and the ecosystem processes of energy and nutrient flow, which could have important implications in the context of both landscape ecology, and issues such as the greenhouse effect, acid rain and biodiversity.
