Location: Pasture Systems & Watershed Management Research2019 Annual Report
Objective 1: Describe and quantify processes controlling agriculturally related environmental contaminants (C, N, and P) to reduce inputs to receiving waters (C2, PS 2.1). Subobjective 1.1: Characterize chemical, physical and biological controls of contaminant mobility and transport in water at pedon, field, landscape and watershed scales. Subobjective 1.2: Characterize the spatial nature and temporal dynamics of transport pathways connecting sources of key agricultural contaminants with surface and ground waters. Objective 2: Adapt and develop management practices that farmers can use to reduce the environmental impacts of agriculturally derived contaminants on receiving waters (C1: PS 1.5; C2: PS 2.4; C3: PS 3.1 and 3.2; C4: PS 4.2). Subobjective 2.1: Identify, evaluate, and develop fertilizer, manure, tillage, irrigation and drainage management practices that improve production use efficiency and minimize off site transfers to surface and ground waters. Subobjective 2.2: Develop new technologies, management practices and decision support tools that recognize the spatial variability of the landscape and focus mitigating efforts on critical source areas or critical pathways. Objective 3: Conduct plot, field and watershed studies to understand processes that link cranberry production to water resources and develop appropriate conservation practices to protect water quality (C1: PS 1.5; C2: PS 2.4; C3: PS 3.1 and 3.2; C4: PS 4.2; NP305 C1: PS 1B). Subobjective 3.1: Characterize temporal and spatial patterns of N and P discharge from cranberry farms. Subobjective 3.2: Develop new technologies and management practices that improve water quality and enhance water use efficiency on cranberry farms. Objective 4: As part of the LTAR network, and in concert with similar long-term, land-based research infrastructure in the mid-Atlantic Region, use the Upper Chesapeake Bay Experimental Watersheds LTAR site to improve the observational capabilities and data accessibility of the LTAR network and support research to sustain or enhance agricultural production and environmental quality in agroecosystems characteristic of the region. Research and data collection are planned and implemented based on the LTAR site application and in accordance with the responsibilities outlined in the LTAR Shared Research Strategy, a living document that serves as a roadmap for LTAR implementation. Participation in the LTAR network includes research and data management in support of the ARS GRACEnet and/or Livestock GRACEnet projects. (C4: PS 4.1; NP 212 C1: PS 1B; NP 216 C5: PS 5A) Subobjective 4.1: Support the LTAR common observatory by monitoring and modeling long term changes affecting water resources and contributing to LTAR’s common database. Subobjective 4.2: Support LTAR’s common experiment and Dairy Agro-ecological Working Group (DAWG) water research objectives by comparing water resource impacts of a long term conventional dairy forage rotation (corn, soybean, and alfalfa) with a diversified dairy forage rotation that, in addition, includes winter cover crops, perennial grasses for bioenergy feedstock, and grazed pasture.
Research will span the Chesapeake Bay and Buzzards Bay watersheds, relying upon core sites in the Atlantic Coastal Plain (Manokin watershed, MD; Buzzards Bay watershed, MA), Appalachian Piedmont (Conewago watershed, PA), Appalachian Valley and Ridge (Mahantango Creek watershed, PA and Spring Creek watershed, PA), and Allegheny Plateau (Anderson Creek watershed, PA). Research emphases will vary across these locations, reflecting issues that are of current management or scientific relevance as well as constraints imposed by available resources. Our primary distinction is between the Atlantic Coastal Plain (in the Chesapeake and Buzzards Bay watersheds) and the upland physiographic areas of the Chesapeake Bay watershed, as hydrologic flow paths are dramatically different in these landscapes (subsurface flow is the dominant hydrologic pathway in the Atlantic Coastal Plain, whereas overland and shallow lateral flows are the major pathways in the upland provinces). We have landowner contacts and research collaborators at all major (core) sites and have a research infrastructure that enables routine measurement and chemical sampling of surface runoff, subsurface flow, and stream flow. When necessary, we move infrastructure from one location to another to provide a greater intensity of observations. We combine field observations with laboratory experiments in which greater control may be obtained over indirect variables. Our process-oriented research (Objective 1) involves observational and experimental studies, using parametric and nonparametric statistics to quantify temporal and spatial trends or to determine differences between management/land use, landscape units, and watershed components. Our applied research (Objectives 2-4) includes experimental studies, remote sensing and modeling. Experimentation involves a high degree of replication due to the inherent variability in processes impacting water quality. We have strong in-house statistical capability and, when necessary, consult with outside statisticians to ensure confidence in our findings.
Early results for the wetland lysimeter leaching study suggest that inorganic P (phosphorus) ready leaches through wetland soils, but organic P forms bind to soil and organic particles and do not leach completely through the lysimeters. Urea production in stagnant ditch drainage waters is associated with higher populations of anaerobic and facultative microbes. Monitoring data from riparian seeps in Pennsylvania landscapes confirm that seeps are a major conduit for nitrates reaching surface waters and nitrate concentrations are related to source areas up slope from the seep. Transit time modeling with chloride was accomplished in collaboration with Johns Hopkins University. John Hopkins University used ranked StorAge Selection (rSAS) models to estimate transit time distributions in the WE-38 watershed using long-term chloride data in precipitation and stream water, and then used ParFlow (a fully integrated hydrologic model that supports particle tracking) to corroborate these transit time estimates. The results of this work were summarized in paper that is currently in review with Water Resources Research. Transit time modeling with stable isotopes is planned for early 2020. A transect of nested wells will be installed later this summer in the FD-36 watershed. Shortly after installation, the wells will be sampled for age-dating tracers, including SF6. Data from the wells will also support an LTAR-wide study of watershed lag times with chiral MESA (led by ARS-Hydrology and Remote Sensing Laboratory). Electrical resistivity imaging (ERI) studies will be expanded as a result of additional funding obtained through a NIFA grant. Manure injection reduces N (nitrogen) losses in runoff and is marginally economically feasible due to reduced N loss by ammonia volatilization. Field studies to investigate cover management impacts on forage production and water quality, led by a Pennsylvania State University graduate student, have been completed, and a manuscript is expected by fall. For the purpose of decreasing dissolved P susceptible to loss in runoff, soils should receive small, frequent additions of gypsum, and magnesium rich lime should be used to balance the calcium/magnesium ratio. The removal of P from poultry manure using the MAPHEX System is not likely feasible (or economic) for farmers due to the necessity of adding large amounts of water to turn the manure into a slurry which can be run on the System. A provisional patent on the recovery and reuse of diatomaceous earth was filed in August 2018 and a full patent and supporting journal article on those results will be filed later this year. Data from the bioreactor study was used to support reduction efficiencies for N removal by bioreactors in the Chesapeake Bay model. Riparian buffers in the Chesapeake Bay Watershed should be installed as a part of a suite of practices designed to prevent upslope processes from defeating the effectiveness of the buffer. Quantitative comparisons of runoff forecasting tools indicate some challenges in objectively comparing tools with different forecast outputs (e.g., forecasted runoff amounts versus soil moisture states). Initial SWAT simulations of the decision support tool scenarios developed in years 1 and 2 are planned for later in 2019. A manuscript illustrating the effects of renovation on soil forming processes in cranberry bogs is currently under review. A paper describing the use of aluminum sulfate as a phosphorus control agent in cranberry floodwaters was published, and a complimentary manuscript on the factors affecting phosphorus losses in cranberry floodwaters has been accepted. A manuscript on the forms of nitrogen and phosphorus losses from cranberry bogs is being prepared for submission later this year. The unit received increased funds for research on cranberry water and nutrient management in FY18 and again in FY19. The increases will support a new scientist position with an emphasis on precision agriculture management of cranberry production. Specifically, water, nutrient, and pest management strategies to grow the most profitable cranberry based on color, firmness, rot, and yield will be developed. Comparative analysis of continuous monitoring and thrice weekly sampling are continuing and have been delineated in a manuscript currently under review by Journal of Soil and Water Conservation. SWAT modeling results from the LTAR watersheds show that in-field conservation practices, such as no-till, cover crops, and integrated pest management are among the most effective and economically feasible conservation practices for reducing nutrient losses. Treatments for the plot-scale LTAR Common Experiment are in place and the full suite of measurements are being taken. The field-scale site for the Common Experiment has been obtained through a lease with one of the largest dairies in Pennsylvania, eddy covariance and phenocam towers have been installed, and background data is being obtained in 2019.
1. Manure injection impacts multiple nutrient loss pathways. Manure injection was previously shown to reduce ammonia emissions, odor, and surface runoff of phosphorus, but other impacts, especially impacts on groundwater quality, have been difficult to assess and are not clearly understood. Therefore, hydrologically isolated, plot-scale lysimeters were constructed to allow coupled measurement of surface and subsurface water quality, soil parameters, air emissions, and crop productivity. Studies on the lysimeter plots confirmed that injection reduced runoff phosphorus losses, but showed that injection caused a moderate increase in subsurface nutrient losses following some large rainfall events and substantially higher emissions of the greenhouse gas nitrous oxide, compared to surface application, in the month following application. Manure injection is marginally economically feasible due to reduced N loss by ammonia volatilization.
2. P350 – A global platform for coordinating research on agricultural phosphorus. Phosphorus is an essential fertilizer nutrient whose use in agriculture underscores modern crop yields and profitability, but also contributes to increases in nutrients, the most pervasive water quality dilemma found across the world. In recent years, there has been an understanding that, to address the resource and environmental concerns arising from phosphorus management, global strategies are required that comprehensively address the many dimensions of phosphorus management. Therefore, as part of a global celebration of the 350th Anniversary of the discovery of phosphorus, the first element identified by modern science, ARS scientists at University Park, Pennyslvania, Columbus, Ohio, Fayetteville, Arizona, Temple, Texas and Kimberly, Idaho helped to form a global phosphorus research network, the P350 Network, with partners in government, university and industry institutions in Europe (England, Finland, Ireland, Norway, Sweden), North America (Canada, United States), South America (Brazil, Uraguay), and the Pacific Rim (Australia, China, New Zealand). Their coordinated research promises to bring global technologies and decision support systems to local problems.
3. LTAR – Connecting agriculture in Pennsylvania to national priorities. Agriculture in the United States is amongst the most productive on earth, but farmers are increasingly asked to balance the pursuit of profitability with national priorities related to resource conservation and environmental quality. At the same time, there is recognition that rural prosperity is inextricably linked to agriculture, even as the nation’s farmers constitute roughly 1% of the national population. ARS scientists at University Park, Pennsylvania helped to lead government and university scientists from 18 sites across the country in implementing network research to advance the sustainability of U.S. agriculture. Their contributions to the Long Term Agroecological Research Network helped to establish common objectives for research that, in Pennsylvania, will increase productivity of cropping systems by harnessing GxExM research (GeneticsxEnvironmentxManagement), incorporating technologies that minimize agriculture’s environmental footprint and advance information-based rural economies.
Hile, M.L., Gabian-Wheeler, E., Murphy, D.J., Meinen, R.J., Hill, D.A., Elliot, H.A., Bryant, R.B. 2018. Gypsum bedding impact on hydrogen sulfide release from dairy manure storages. Biological Engineering (ASABE). 61(3):937-941. https://doi.org/10.13031/trans.12463.
Dari, B., Nair, V.D., Sharpley, A., Kleinman, P.J., Franklin, D., Harris, W.G. 2018. Consistency of the threshold phosphorus saturation ratio across a wide geographic range of acid soils. Agrosystems, Geosciences & Environment. 1:180028. https://doi.org/10.2134/age2018.08.0028.
Duncan, E., Dell, C.J., Kleinman, P.J., Beegle, D. 2017. Nitrous oxide and ammonia emissions from injected and broadcast applied dairy slurry. Journal of Environmental Quality. 46:36-44. https://doi.org/10.2134/jeq2016.05.0171.
Duncan, E., Kleinman, P.J., Folmar, G.J., Saporito, L.S., Feyereisen, G.W., Buda, A.R., Vitko, L., Collick, A., Drohan, P., Lin, H., Bryant, R.B., Beegle, D. 2017. Development of field-scale lysimeters to assess management impacts on runoff. American Society of Agricultural and Biological Engineers. 60:419-429. https://doi.org/10.13031/trans.11901.
Kleinman, P.J., Spiegal, S.A., Rigby Jr., J.R., Goslee, S.C., Baker, J.M., Bestelmeyer, B.T., Boughton, R., Bryant, R.B., Cavigelli, M.A., Derner, J.D., Duncan, E.W., Goodrich, D.C., Huggins, D.R., King, K.W., Liebig, M.A., Locke, M.A., Mirsky, S.B., Moglen, G.E., Moorman, T.B., Pierson Jr., F.B., Robertson, G., Sadler, E.J., Shortle, J., Steiner, J.L., Strickland, T.C., Swain, H., Williams, M.R., Walthall, C.L., Tsegaye, T.D. 2018. Advancing the sustainability of US agriculture through long-term research. Journal of Environmental Quality. 47(6):1412-1425. https://doi.org/doi:10.2134/jeq2018.05.0171.
Duncan, E.W., Kleinman, P.J., Beegle, D.B., Rotz, C.A. 2017. Coupling dairy manure storage with injection to improve nitrogen management: whole-farm simulation using the integrated farm system Model. Agricultural and Environmental Letters. doi:10.2134/ael2016.12.0048.
Duncan, E.W., Kleinman, P.J., Beegle, D., Dell, C.J. 2019. Nitrogen cycling trade-offs with broadcasting and injecting dairy manure. Nutrient Cycling in Agroecosystems. 114(1):57-20. https://doi.org/10.1007/s10705-019-09975-2.
Spiegal, S.A., Bestelmeyer, B.T., Archer, D.W., Augustine, D.J., Boughton, E., Boughton, R., Clark, P., Derner, J.D., Duncan, E.W., Cavigelli, M.A., Hapeman, C.J., Harmel, R.D., Heilman, P., Holly, M.A., Huggins, D.R., King, K.W., Kleinman, P.J., Liebig, M.A., Locke, M.A., McCarty, G.W., Millar, N., Mirsky, S.B., Moorman, T.B., Pierson, F.B., Rigby, J.R., Robertson, G., Steiner, J.L., Strickland, T.C., Swain, H., Wienhold, B.J., Wulfhorts, J., Yost, M., Walthall, C.L. 2018. Evaluating strategies for sustainable intensification of U.S. agriculture through the Long-Term Agroecosystem Research network. Environmental Research Letters. 13(3):034031. https://doi.org/10.1088/1748-9326/aaa779.
Miller, M.D., Gall, H.E., Buda, A.R., Saporito, L.S., Veith, T.L., White, C.M., Williams, C.F., Brasier, K.J., Kleinman, P.J., Watson, J.E. 2018. Load-discharge relationships reveal the efficacy of manure application practices on sediment and phosphorus loss from agricultural fields. Agriculture Ecosystems and the Environment. 272:19-28. https://doi.org/10.1016/j.agee.2018.11.001.
Flaten, D., Sharpley, A., Jarvie, H., Kleinman, P.J. 2019. Reducing unintended consequences of agricultural phosphorus. Better Crops. 103:33-35. https://doi.org/10.24047/BC10316.
Tzilkowski, S.S., Buda, A.R., Boyer, E.W., Bryant, R.B., Kleinman, P.J., Kennedy, C.D., Allen, A.L., Folmar, G.J., May, E.B. 2018. Urea fluctuations in stream baseflow across land cover gradients and seasons in a coastal plain river system. Journal of the American Water Resources Association. 55(1):228-246. https://doi.org/10.1111/1752-1688.12716.
Sebestyen, S.D., Ross, D.S., Shanley, J.B., Elliott, E.M., Kendall, C., Campbell, J.L., Dail, B., Fernandez, I.J., Goodale, C.L., Lawrence, G.B., Lovett, G.M., McHale, P.J., Mitchell, M.J., Nelson, S.J., Shattuck, M.D., Wickman, T.R., Barnes, R.T., Bostic, J.T., Buda, A.R., Burns, D.A., Eshleman, K.N., Finlay, J.C., Nelson, D.M., Ohte, N., Pardo, L.H., Rose, L.A., Sabo, R.D., Schiff, S.L., Spoelstra, J., Williard, K.W. 2019. Unprocessed atmospheric nitrate in waters of the northern forest region in the USA and Canada. Journal of Environmental Science and Technology. 53:3620-3633. https://doi.org/10.1021/acs.est.9b01276.
Gunn, K.M., Holly, M.A., Veith, T.L., Buda, A.R., Prasad, R., Rotz, C.A., Soder, K.J., Stoner, A. 2019. Projected heat stress challenges and abatement opportunities for U.S. milk production. PLoS One. 14(3):1-21. https://doi.org/10.1371/journal.pone.0214665.