2012 Annual Report 1a.Objectives (from AD-416): The overall objective of the project is to maximize bioenergy biomass stability and yield. However, production should be maximized while minimizing environmental impacts at watershed scale. Results from this agreement will determine the environmental impacts of various production strategies and suggest management that will maximize production while minimizing environmental impacts. 1b.Approach (from AD-416): 1) Apply SWAT to the island of Maui, focusing detail on the watersheds that supply water to the existing canal system, using readily available soils, precipitation, sugar cane management, and yield data. 2) Assemble all existing rainfall and temperature data for the island of Maui and use the PRISM model to create a high resolution grid of precipitation and temperature. PRISM accounts for elevation, aspect, and slope when creating the interpolated grid. 3) Verify environmental impacts of optimal-yield sugarcane management practices via on-the-ground monitoring. Use existing USGS stream flow gages and water quality data collected in this study to calibrate and validate SWAT. 4) With the calibrated model, simulate alternative agronomic management of additional fields, including changing feedstocks, and nutrient and water management. Determine water supply and water quality impacts of the various alternatives. 3.Progress Report: The Navy's dependence on oil (petroleum) strains operational planning. Its focus is on securing a sustainable fuel supply. ARS research and models will help determine how best to manage natural resources to allow Office of Naval Research (ONR) sustainability in fuel supply while also promoting ecological services and the local economy in Hawaii. SWAT (Soil and Water Assessment Tool) input files for over 700 integrated management units (sugarcane fields) were developed using spatial data for elevation, land use, soils, stream network, canal network, dams/reservoirs, precipitation, and temperature. Model output was validated against measured sugarcane yields at six locations, and SWAT evapotranspiration algorithms were refined and validated. Web-based software was developed to allow users to remotely run the model, update daily precipitation and irrigation, and automatically map irrigation scheduling requirements on the web. We are currently working on an automated integration with HC&S (Hawaiian Commercial & Sugar Company) management databases with implementation on HC&S computers.