2007 Annual Report 1a.Objectives (from AD-416) Principal focus of the CEAP effort is to produce a national assessment of environmental benefits of conservation programs to support policy decision and program implementation. 1b.Approach (from AD-416) Utilize ARS historical watershed databases to validate the SWAT model and then utilize this model to determine the impact of conservation practices on water quality, soil quality, air quality, and wildlife habitat. 3.Progress Report This report serves to document research conducted under a Reimbursable Agreement between ARS and the Natural Resources Conservation Service (NRCS) as part of the Conservation Effects Assessment Program (CEAP). Additional details of research can be found in the report for the in-house project 6408-13000-017-00D, "Integrated Assessment and Analysis of Physical Landscape Processes that Impact the Management of Agricultural Watersheds." Tracking of fine sediment sources using stable radio-nuclides was conducted in conjunction with determination of magnitudes of sediment-transport. Historical flow and sediment-transport data were used in combination with rapid geomorphic assessments to determine ranges of suspended-sediment transport for stable and unstable streams in ecoregions that included CEAP-Benchmark watersheds. These values were compared to sediment loadings from the CEAP-Watershed to determine whether they represent conditions of accelerated transport/erosion. In the majority of cases it was found that streambank erosion was important in the CEAP-Watershed channels and that sediment loadings were far in excess of those for stable streams in the same ecoregion. Research results are critical to the NRCS in evaluating whether sediment quantity is a water-quality issue and if so, where on the landscape erosion-control practices need to implemented to protect downstream habitat and water quality. Progress was documented through reports and invited presentations at the ARS CEAP-WAS Annual Meeting held in Ames, Iowa, May 2006, and at the Soil and Water Conservation Society national meetings and the joint CEAP Workshop held in Tampa, Florida, July 2007.