1a. Objectives (from AD-416):
The overall goal of research is to identify chemical and hydrologic processes controlling nutrient export at farm and watershed scales, locate where they occur on the landscape, quantify what changes occur during transport in stream to receiving waters, and develop, implement, and assess cost-effective Best Management Practices (BMPs) control of nutrient export at farm and watershed levels. Specific objectives are: 1. Quantify impacts of current and alternative fertilizer, manure, crop, and grazing management practices on nutrient cycling within soils at point and field scales. Effective June 15, 2007, research on Objective 1.3: “Quantify NH3 and N2O emissions from urine deposition during grazing” was terminated, and this effort was redirected to Objectives 3.2 and 3.3. 2. Evaluate landscape-scale controls on nutrient transfers to quantify aggregate N and P losses from farming systems and watersheds typical of the Northeast. 3. Identify and quantify processes occurring in the stream channel that control the transfer of nutrients lost from the farm to lakes, reservoirs, and estuaries. Effective June 15, 2007, resources previously allocated to Objective 1.3 were redeployed to accelerate work on Objectives 3.2: “Selecting chemical amendments to reduce P mobility in terrestrial and aquatic systems” and Objective 3.3: “Control nutrient export from ditch drained agriculture” with a focus on the use of industrial byproducts coupled with drainage practices in agricultural and urban landscapes to minimize impact on water quality within the Chesapeake Bay watershed. 4. Determine effectiveness of BMPs in the Cannonsville/Town Brook Watershed and other appropriate watersheds (CEAP-related). 5. Develop, enhance, and apply models and user-oriented indices at field, farm, and watershed scales to evaluate BMPs and N and P export from watersheds.
1b. Approach (from AD-416):
Most of the proposed research will be conducted at three sites in the Northeast U.S.: Mahantango Creek Watershed, PA; Town Brook Watershed, NY; and Manokin River Watershed, MD (Figure 3). These sites are located in agriculturally important areas of the Northeast and reflect the local land use practices. We already have established contacts with landowners at each site and have developed an infrastructure for routine measurement and chemical sampling of surface runoff, subsurface flow, and streamflow. Lease agreements already in place make it easy for us to change management and/or implement alternative practices for cause-and-effect studies on water quality impacts. Also included in this section is a description of the National P Research Project (NPRP) rainfall simulation protocol. Experimental design will vary as a function of each specific research objective and site characteristics. In all cases, appropriate experimental design and statistical analyses will be used.
3. Progress Report:
Over the course of the project, all major objectives were met. Project accomplishments included (but were not limited to): (a) ditch filters and manure injectors labeled by USEPA as “next generation nutrient management practices” for the Chesapeake Bay and project research identified in state Watershed Implementation Plans, (b) new nitrogen recommendations for canopy sensor developed for corn in PA, (c) new tracers of particulate phosphorus developed to improve the study of phosphorus in runoff, (d) defined “legacy phosphorus” and demonstrated its role in watershed management, (e) 40 years of Mahantango Creek watershed data available in STEWARDS on-line database, (f) standard test for phosphorus in manures adopted by laboratories across North America, (g) developed new approach to predicting nutrient runoff using weather forecasts. In FY 2012 the following activities took place. Under objective 1, we led the development of a white paper prioritizing manure management needs in the Chesapeake Bay Watershed. This consensus document, published in Journal of Soil and Water Conservation, included input from industry, conservation, government and university experts. Under objective 2, we published findings summarizing five years of intensive watershed monitoring in ARS’s Mahantango Creek watershed, highlighting the spatial variability and transient nature of nitrogen and phosphorus runoff (hot moments and hot spots), yet pointing to significant opportunities for cover cropping and reduced tillage to control nutrient losses not just in the Mahantango Creek watershed, but across the Ridge and Valley province of the Chesapeake Bay watershed. Under objective 3, we published a series of articles summarizing the state-of-the science in trapping phosphorus in runoff water, reviewing the performance of gypsum-based ditch filter for phosphorus, and describing the properties of spent gypsum, to assess its potential as a soil amendment. Under objective 4, a series of articles were developed describing the Mahantango Creek watershed database, which includes 40 years of continuous flow and precipitation monitoring, and over 30 years of water quality data. Under objective 5, we published a proof-of-concept paper describing the use of empirical runoff models to develop a next-generation site assessment tool (the Fertilizer Forecaster) for nitrogen and phosphorus. We demonstrated that readily-available weather forecast variables can be used to predict runoff over short time intervals, helping farmers to assess when and where to apply fertilizers and manures.
1. Using weather forecasts to help fertilizer wash into (rather than wash off of) the soil. ARS researchers at University Park, Pennsylvania partnered with Penn State colleagues, and unveiled a new statistical approach to predict the likelihood that rainfall will either infiltrate into or runoff agricultural soils. Their research, published in the Journal of Soil and Water Conservation, describes the development of empirical models from historical runoff monitoring studies and the application of these models to predicting runoff potential from other areas. This approach is one of several they will evaluate in developing the Fertilizer Forecaster, a short-term decision support tool for farmers applying fertilizers and manures, recently funded by USDA’s Agriculture and Food Research Initiative (AFRI).
2. Balancing livestock production and environmental concerns in the Chesapeake Bay region. ARS researchers at University Park, Pennsylvania led efforts to identify priorities in manure management in the Chesapeake Bay region. Working with industry, government, conservation and environmental organizations, ARS scientists involved in ARS national program 211 (Water Availability and Watershed Management) and 214 (Agricultural and Industrial Byproducts) documented priority issues related to manure management in the region. Their findings, published in the Journal of Soil and Water Conservation, are intended to inform efforts aimed at restoring the health of the Chesapeake Bay while sustaining the prosperity of livestock production in the region.
Lee, C., Hristov, A.N., Dell, C.J., Feyereisen, G.W., Kaye, J., Beegle, D. 2012. Effect of dietary protein concentration on ammonia and greenhouse gas emitting potential of dairy manure. Journal of Dairy Science. 95:1930-1941.