The Utility of Biochar in Riparian Buffer Zones; The Environmental Fate of Innovative Agricultural Fertilizers in Southern Illinois.

Agricultural runoff is the number one nonpoint source pollutant in the Midwest. During rain events, excess nutrients and sediment can be transported from fertilized fields to receiving waters resulting in eutrophication of streams and rivers and ultimately lead to hypoxia in the Gulf of Mexico. Researchers and farmers have been working together to find solutions to ensure that crop production remains at current levels without jeopardizing  water quality or the health of the ecosystem. Over the past four decades riparian buffers have proven their effectiveness at attenuating nutrients and sediment in agricultural runoff; however, fertilizers have rapidly evolved over the recent years and little is known about their environmental fate and transport. This study will focus on the attenuation of Environmentally Smart Nitrogen (ESN) and phosphorus with a slow release additive (i.e., Avail ®) as they move via surface runoff through flumes planted with multiple riparian buffer species and/or amended with non-activated or activated biochar with compost (i.e., horse manure and mushroom compost).  Fifteen flumes were installed in 2008 in a southern Illinois agricultural field and 15 additional flumes were established adjacent to the existing flumes in June 2012. Each flume was vegetated or amended with one of ten treatments, each of which had been replicated three times. In May 2012 an upslope corn plot was fertilized at a rate of 30.7 kg ha^-1 of ESN, 13.8 kg ha^-1 of triple superphosphate, and 18.8 kg ha^-1. The study will be examining the following treatments: 1) giant cane (Arundinaria gigantea) 2008 planting; 2) giant cane 2012 planting; 3) Kentucky bluegrass (Poa pratensis); 4) orchardgrass (Dactylis glomerata L.);  5) biochar; 6) biochar and giant cane; 7) biochar, giant cane, and compost; 8) giant cane and compost; 9) corn; and 10) a non-amended, non-vegetated control. To better determine the influence of these treatments on soil quality, soil samples were collected prior to the application of soil amendments and will continue to be assessed annually. Water samples are being collected from surface runoff following two artificial flow events and subsequent natural rain events at the downslope end of each flume. These data will provide insight on the performance of various buffer species and the utility of biochar and soil amendments on the attenuation of innovative fertilizers in agricultural runoff.