Watershed‐scale impacts of bioenergy crops on hydrology and water quality using improved SWAT model

分类： 生物学 >> 植物学 >> 植物生态学和植物地理学 提交时间： 2016-05-04

Raj Cibin Elizabeth Trybula Indrajeet Chaubey Sylvie M. Brouder Jeffrey J. Volenec

摘要： Cellulosic bioenergy feedstock such as perennial grasses and crop residues are expected to play a significant role in meeting US biofuel production targets. We used an improved version of the Soil and Water Assessment Tool (SWAT) to forecast impacts on watershed hydrology and water quality by implementing an array of plausible land-use changes associated with commercial bioenergy crop production for two watersheds in the Midwest USA. Watershed-scale impacts were estimated for 13 bioenergy crop production scenarios, including: production of Miscanthusgiganteus and upland Shawnee switchgrass on highly erodible landscape positions, agricultural marginal land areas and pastures, removal of corn stover and combinations of these options. Water quality, measured as erosion and sediment loading, was forecasted to improve compared to baseline when perennial grasses were used for bioenergy production, but not with stover removal scenarios. Erosion reduction with perennial energy crop production scenarios ranged between 0.2% and 59%. Stream flow at the watershed outlet was reduced between 0 and 8% across these bioenergy crop production scenarios compared to baseline across the study watersheds. Results indicate that bioenergy production scenarios that incorporate perennial grasses reduced the nonpoint source pollutant load at the watershed outlet compared to the baseline conditions (020% for nitrate-nitrogen and 356% for mineral phosphorus); however, the reduction rates were specific to site characteristics and management practices.

同行评议状态:待评议

 点击量 1566  下载量 806  评论