摘要

AS climate changes, the uncertainty of water availability, changing magnitudes of nonpoint-source pollution, and uncertainty of best management practice (BMPs) effectiveness are issues that watershed managers and stakeholders must consider and plan for The objective of this study was to determine how BMP effectiveness will be affected by climate change using the Soil and Water Assessment Tool (SWAT). Using downscaled monthly precipitation and temperature data output from the Community Climate System Model (CCSM), daily precipitation and temperature data were produced based on observed weather station data for the Tuttle Creek Lake watershed in Kansas and Nebraska. The A1B, A2, and B1 SRES emissions scenarios were compared to historical CCSM model output. Eight agricultural BMPs were physically represented within SWAT and compared across climate scenarios. Water yield, surface runoff, baseflow, sediment load, nitrogen load, and phosphorus load increased in all three future climate scenarios. Terraces, contour farming, and native grass were determined to be the most effective in pollution load reduction and percent efficiency at the field and watershed scales in future scenarios. Porous gully plugs and filter strips showed no significant changes in pollution load or percent reduction. Grazing management, no-tillage, conservation tillage, and grazing management percent and load reduction in future scenarios varied at the field and watershed scales. This study demonstrates that BMP performance in terms of sediment, nitrogen, and phosphorus reduction significantly changes in future climate scenarios at the field scale, while performance generally does not change significantly at the watershed scale.

  • 出版日期2011-2