PROGRAM TITLE: Ecological Diversity (Formerly "Terrestrial Ecology") ACTIVITY STREAMS: Processes, Consequences, Modeling, Assessment SCIENCE ELEMENT:Ecosystem Dynamics NATIONAL SCIENCE FOUNDATION PROGRAM DESCRIPTION: Ecological processes influenced by or contributing to changes in the global climate and other natural systems ultimately are dependent on the diversity of organisms and their influence on system dynamics. An improved understanding of ecological processes requires knowledge of the species, populations, and spatial patterns that contribute to total community composition (including microbial communities), survival and adaptation mechanisms, natural rates of change, and human-caused changes such as exotic invasions or extinctions. Diversity can be defined as the number of different items and their relative frequency. For biological and ecological diversity, these items and processes are organized at many levels, ranging from complete ecosystems to the chemical structures that are the molecular basis of heredity. Projects supported by this program will include biotic surveys and inventories and research on the evolutionary history of organisms and species and the functions and interactions of populations, communities, and ecosystems. This new program is focused on research to determine the potential effects of global change on the biological and ecological diversity of managed and unmanaged ecosystems and the resulting effects of altered diversity on ecosystem function. Operation of the program consists of peer- based merit review of proposals submitted by investigators. Outcomes of research funded through this program are disseminated through scientific publications and presentations. Knowledge advanced through research funded by this program will help the US/GCRP meet many of the milestones identified in April 1992, especially those dealing with the ecosystem studies. Oversight and evaluation of the program will be provided through the NSF Biological Sciences Advisory Committee and committees of visitors charged by division directors in the Directorate for Biological Sciences. STAKEHOLDERS: Ecological diversity has been identified as a major research need by a number of groups, including the multi- agency team developing a "Terrestrial Ecosystem" initiative for the US/GCRP in 1993, the NRC committee that produced a 1994 report entitled The Role of Terrestrial Ecosystems in Global Change, and participants in the 1994 CENR-related, NRC-convened forum on Environmental and Natural Resources Research. Within NSF, the Ecological Diversity Program complements the Ecological Rates of Change, Land-Margin Ecosystem Research, and Water and Energy: Atmosphere, Vegetation, and Earth (WEAVE) programs as primary means of addressing fundamental problems in ecological research related to global change. Development and operation of these programs is conducted by NSF in partnership with other US/GCRP agencies. To facilitate synthesis and comparison, researchers supported through the Ecological Diversity Program will be encouraged to use ecological research sites in networks and appropriate electronic data bases. These networks may consist of sites supported by NSF (e.g., LTER and LMER site-based networks) or by other federal agencies (e.g., National Parks, Estuarine Reserves, Wildlife Refuges, and Forest and Agricultural Experiment Stations). POLICY RELEVANCE: Comparative studies in Ecological Diversity are important because they are the basis for synthesis and generation of principles used in ecosystem management. In the short run, new knowledge obtained through research on these topics will assist in identification of critical gaps in understanding, thereby helping to establish future priorities for research. Longer-term payoffs will be evident as greater knowledge is gained of the ways of the vulnerability of managed and unmanaged ecosystems to changing environmental conditions. This advanced knowledge will also help refine integrated models used for assessments of the impacts of future global changes on ecosystems and the likely efficacy of various mitigation and adaptation strategies.