This project is designed to further understanding of relations among climate, vegetation, and streamflow across a range of ecosystem conditions and to advance intersite activities among LTER and nonLTER sites. The overall objective of this proposal is to describe streamflow hydrology in a wide range of sites by elucidating streamflow response to a range of climatic, vegetation, and disturbance factors operating at time scales ranging from decadal to diel. We expect to demonstrate how steamflow responds to vegetation and climate at each of these scales, and how this inherent coupling of climate, vegetation and streamflow controls streamflow response to disturbance and hence aspects of stream ecology. The initial research phase of the project involves comparative analysis of long-term steamflow records from Andrews, Coweeta, and Hubbard Brook LTER sites and the Caspar Creek Experimental Watersheds site (USDA Forest Service/State of California). These forest sites encompass a broad range of climatic (e.g., precipitation amount and seasonality, degree of snow influence) and vegetation (e.g., deciduous vs. conifer, leaf area index) conditions. Subsequently, they will involve a much larger group of LTER and other sites in a workshop and associated activities designed to develop site characterization and cross-site analysis for broader range of site conditions. This work will include use of hydrologic models to examine hypothese concerning controls on water balances at the time scales of interest. Representatives of the Climate and Stream Ecology Committees of LTER will take part in workshop planning and conduct. Products of the overall effort will include: (1) on -line data bases with common variables/time resolution between sites, (2) an LTER publication similar to the Stream Research in the LTER Network Publication No. 15, and (3) journal articles from the comparative analyses conducted for the small set of sites and for the larger set of sites.
