Cellulosic and agricultural bio-energy crops can be utilized as feedstock source for bio-fuels production and provide environmental benefits such as hydrology, water quality. This study compared potential feedstock yi...Cellulosic and agricultural bio-energy crops can be utilized as feedstock source for bio-fuels production and provide environmental benefits such as hydrology, water quality. This study compared potential feedstock yield and water quality benefit scenarios of six bio-energy crops: Miscanthus (Miscanthus-giganteus), Switchgrass (Panicum virgatum), Johnsongrass (Sorghum halepense), Alfalfa (Medicago sativa L.), Corn (Zea mays), and Soybean {Glycine max (L.) Merr.} at the watershed scale using Soil and Water Assessment Tool (SWAT) model. The SWAT model was calibrated (1998 to 2002) and validated (2003 to 2010) using monthly measured USGS stream flow data. Model was further verified using available monthly sediment yield, and county level NASS corn and soybean yield data within the watershed. The long-term average annual potential feedstock yield as an alternative energy source was determined the greatest when growing Miscanthus grass scenario (21.9 Mg/ha) followed by Switchgrass (15.2 Mg/ha), Johnsongrass (12.1 Mg/ha), Alfalfa (7 Mg/ha), Corn (5.9 Mg/ha), and Soybean (2.35 Mg/ha). Model results determined the least amount of average annual sediment yield (1.1 Mg/ha) from the Miscanthus grass scenario and the greatest amount (12 Mg/ha) from the corn crop scenario. About 11% less annual average surface water flow from the watershed could be anticipated when converting land areas from soybean to Miscanthus grass. The results of this study suggested that growing Miscanthus grass in the UPRW would have the greatest potential feedstock yield and water quality benefits. The results of this study may help in developing future watershed management programs.展开更多
Soil degradation,characterized by declines in nutrient status and simultaneous accumulation of pesticide residues,is a major problem affecting agricultural ecosystems.Previous studies indicate that biochar application...Soil degradation,characterized by declines in nutrient status and simultaneous accumulation of pesticide residues,is a major problem affecting agricultural ecosystems.Previous studies indicate that biochar application to soil has promise as a practical method to alleviate these pressures:increasing crop yield and enhancing pesticide degradation.Here,we review the roles of biochar in both chemical and biological promotion of pesticide degradation and the potential benefits of biochar relating to the efficiency of fertilizer use,availability of nutrients,and nutrient exchange.Biochar typically has a high surface area featuring many functional groups,a high cation exchange capacity,and high stability.Major factors that impact on the nutrient retention characteristics of biochar(e.g.,feedstock,pyrolysis temperature,and application rate) are also discussed herein.Nonetheless,more studies of the long-term impacts on soil properties from biochar addition are still required before it can be possible to accurately quantify the sustainability of this approach to sequester carbon and restore soil function.展开更多
文摘Cellulosic and agricultural bio-energy crops can be utilized as feedstock source for bio-fuels production and provide environmental benefits such as hydrology, water quality. This study compared potential feedstock yield and water quality benefit scenarios of six bio-energy crops: Miscanthus (Miscanthus-giganteus), Switchgrass (Panicum virgatum), Johnsongrass (Sorghum halepense), Alfalfa (Medicago sativa L.), Corn (Zea mays), and Soybean {Glycine max (L.) Merr.} at the watershed scale using Soil and Water Assessment Tool (SWAT) model. The SWAT model was calibrated (1998 to 2002) and validated (2003 to 2010) using monthly measured USGS stream flow data. Model was further verified using available monthly sediment yield, and county level NASS corn and soybean yield data within the watershed. The long-term average annual potential feedstock yield as an alternative energy source was determined the greatest when growing Miscanthus grass scenario (21.9 Mg/ha) followed by Switchgrass (15.2 Mg/ha), Johnsongrass (12.1 Mg/ha), Alfalfa (7 Mg/ha), Corn (5.9 Mg/ha), and Soybean (2.35 Mg/ha). Model results determined the least amount of average annual sediment yield (1.1 Mg/ha) from the Miscanthus grass scenario and the greatest amount (12 Mg/ha) from the corn crop scenario. About 11% less annual average surface water flow from the watershed could be anticipated when converting land areas from soybean to Miscanthus grass. The results of this study suggested that growing Miscanthus grass in the UPRW would have the greatest potential feedstock yield and water quality benefits. The results of this study may help in developing future watershed management programs.
基金financially supported by the National Natural Science Foundation and Innovation Group of China(Nos.41271332 and 51521006)
文摘Soil degradation,characterized by declines in nutrient status and simultaneous accumulation of pesticide residues,is a major problem affecting agricultural ecosystems.Previous studies indicate that biochar application to soil has promise as a practical method to alleviate these pressures:increasing crop yield and enhancing pesticide degradation.Here,we review the roles of biochar in both chemical and biological promotion of pesticide degradation and the potential benefits of biochar relating to the efficiency of fertilizer use,availability of nutrients,and nutrient exchange.Biochar typically has a high surface area featuring many functional groups,a high cation exchange capacity,and high stability.Major factors that impact on the nutrient retention characteristics of biochar(e.g.,feedstock,pyrolysis temperature,and application rate) are also discussed herein.Nonetheless,more studies of the long-term impacts on soil properties from biochar addition are still required before it can be possible to accurately quantify the sustainability of this approach to sequester carbon and restore soil function.
