2012 Annual Report 1a.Objectives (from AD-416): Provide science-based data, results and information to routinely inform conservation decisions affecting wetland ecosystems and the services they provide. Develop a broad collaborative foundation that facilitates the production and delivery of scientific data, results and information. 1b.Approach (from AD-416): Conduct collaborative regional investigations to: - quantify wetland ecosystem services across an alteration gradient in agricultural landscapes; - interpret effects of conservation practices and programs, and the effectiveness (i.e., the type, location, land treatment, design and/or management) of conservation practices on ecosystem services; and - identify multiple-scale factors that influence the capacity for a wetland to provide an ecosystem service within a range of estimates. 3.Progress Report: Research carried out under this agreement focused on the transport of phosphorus and arsenic in ditches of the Delmarva Peninsula. More than 1200 water samples obtained from field and public drainage association ditches were analyzed for phosphorus, arsenic, and other elements. The interactions between phosphorus and arsenic were reported in five invited talks and two invited poster presentations as well as in a published journal article and book chapter. This work garnered national attention, and we continue to expand research on the occurrence and extent of arsenic transport from the farm to receiving waters. Funds for this project were utilized by the University Park ARS team, as well as to support an inter-agency agreement with the US Geological Survey. The ARS focus for the 2012 fiscal year has been on sediment/phosphorus interactions in wetland systems. 200 soil samples obtained from wetlands of three types (Natural, Prior Converted, and Restored) were analyzed for phosphorus, arsenic, and other elements. We found that there are strong differences between wetland types regarding the chemical controls on phosphorus movement. Specifically, the phosphorus sorbtion capacity of sediments is strongly governed by amorphous forms of iron and aluminum, and there are marked differences of those between wetland types. This work was recently highlighted in a special symposium talk and is being developed into a manuscript which will serve as a final report. USGS efforts focused on the development and calibration of a Hydrologic Landscape Region (HLR) model that. 1)delineates moisture variables in agricultural and wetland landscapes, and. 2)uses that information to predict potential nitrogen removal in those systems. In 2012, the working HLR model was completed, and further work was done to delineate the details of groundwater movement and nitrogen mineralization at selected wetlands sites. This work was recently reported on in a special symposium talk on the Mid-Atlantic CEAP Project, and the final report is currently in review for publication as a USGS Scientific Investigations Report.