Project Number: 6218-13000-010-00
Project Type: Appropriated

Start Date: Feb 28, 2007
End Date: Feb 27, 2012

Objective:
To quantify interactive effects of variable climate, dynamic land use, and land management, particularly conservation practices, on surface and subsurface water quality at the watershed scale. Specific objectives are: 1) Develop and implement a multi-site data system to organize, document, manipulate, and compile water, soil, management, and socio-economic data for assessment of conservation practices from ARS Benchmark watersheds; 2) Quantify water quality, water quantity, and soil quality effects of conservation practices across field to watershed scales within the Upper Washita River Watershed; and 3) Quantify accuracy and uncertainty in model output across field to watershed scales and incorporate this information into assessment tools. The anticipated result of the research are new methods to quantify environmental effects of conservation practices implemented on the landscape and tools to support future strategic placement of conservation practices on the landscape.

Approach:
Multi-temporal land use data sets (both current and retrospective) will be developed for incorporation into watershed-scale hydrologic models to determine the effects of changing land use and management on model predictions. Geomorphic assessments and sediment source tracking will be conducted to determine potential sources and contributions of sediments from overland processes and stream banks. The historical and existing hydrologic, geomorphic, geologic, soil, climate, and land use and management conditions that govern the movement of water, sediment, and nutrients through selected sub-basins within the Upper Washita River watershed will be quantified. Hydrologic modeling studies will be conducted at multiple scales to monitor water quantity and quality responses to conservation practice implementation. The soil management assessment framework (SMAF), developed for mid-western soils and cropping conditions, will be used to evaluate the effects of management practices on soil parameters, and evaluate the hydrologic sensitivity to the soil parameters.