AnnAGNPS Model Application for Nitrogen Loading Assessment for the Future Midwest Landscape Study

Abstract

Abstract:The Future Midwest Landscape (FML) project is part of the US Environmental Protection Agency (EPA)'s new Ecosystem Services Research Program, undertaken to examine the variety of ways in which landscapes that include crop lands, conservation areas, wetlands, lakes, and streams affect human well-being. The goal of the FML project is to quantify current and future ecosystem services across the region and to examine changes expected to occur as a result of the growing demand for biofuels. This study is one of several pilots taking place under the umbrella of the FML research project. In this study, the USDA Annualized Agricultural Non-Point Source Pollution (AnnAGNPS) model was applied to the East Fork Kaskaskia River watershed (289. future biofuel target were also simulated and analyzed. All delineations of the study area (coarser to finer) produced satisfactory results in simulating monthly and annual runoff. However, the size of the delineation does impact the simulation results. Finer delineations better represented the actual landscape and captured small critical areas that would be homogenized in coarser delineation. Those small critical areas are important to target to achieve maximum environment benefit. Simulations of alternative future scenarios showed that as corn production increases to meet future biofuel needs, total nitrogen loss increases. For this watershed, total N loss would be more than doubled if converting all corn/soybean rotation (15,871.2 ha) to continuous corn comparing with the base year total N loss which is 11.2 kg/ha. Conservation practices are needed to reduce total nitrogen loss from the watershed. This study provides an important foundation for the larger FML region modeling effort by addressing challenging FML landscape modeling issues such as model selection, need for further model development, and spatial resolution.

SWAT Model Application to Assess the Impact of Intensive Corn-farming on Runoff, Sediments and Phosphorous loss from an Agricultural Watershed in Wisconsin

“…The results in this study are in agreement with previous studies [11][12][13]15] that also demonstrated that implementation of best management practices could reduce increase in TP and sediment loss caused by land use Copyright © 2012 SciRes. JWARP change.…”

“…Vegetative buffers, wetlands and management of fertilizer and manure have been suggested by prior studies to be more effective in reducing sediment and P loss into streams [11,12]. In addition, crop rotation (for instance corn-soybean instead of continuous corn) is known to reduce sediment, nutrient and pesticide loss [13]. Soybean has the ability to fix N and requires low amounts of P fertilizer.…”

Simulating the impacts of bio-fuel crop production on nonpoint source pollution in the Upper Mississippi River Basin

“…This in turn led to a surge of total U.S. planted corn acreage (USDA-NASS, 2007), which remained high relative to long-term historical pattern (USDA-NASS, 2010) and would be close to 36 million hectares for the coming decade (USDA-ERS, 2010). The increase in planted corn acreage which requires high fertilizer application rate is projected to further exacerbate water quality problems within the URMB, the larger Mississippi River watershed, and the Gulf of Mexico (Simpson et al, 2008;Donner and Kucharik, 2008;Secchi et al, 2010;Yuan et al, 2011). Over past years, a variety of conventional best management practices (BMPs) such as riparian buffers, filter strips, and grassed waterways have been employed to reduce nutrient and sediment losses (Osborne and Kovacic, 1993;Mitsch et al, 2001;Syversen, 2005;Sahu and Gu, 2009;USDA-NRCS, 2010).…”

Sediment and total phosphorous contributors in Rock River watershed

“…Agricultural lands that have cornesoybean rotation and "soybean_other" were associated with reduction in TSS and TP. Soybean and other leguminous crops improve soil conditions and fixes nutrients required by corn (Yuan et al, 2011). It is a conservation method that reduces TSS and TP loadings to streams because of reduction in fertilizer and tillage needs.…”