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This study investigated potential changes in flow,total suspended solid (TSS) and nutrient (nitrogen and phosphorous) loadings under future climate change,land use/cover (LULC) change and combined change scenarios in the Wolf Bay watershed,south Alabama,USA.Four Global Circulation Models (GCMs) under three Special Report Emission Scenarios (SRES) of greenhouse gas were used to assess the future climate change (2016-2040).Three projected LULC maps (2030) were employed to reflect different extents of urbanization in future.The individual,combined and synergistic impacts of LULC and climate change on water quantity/quality were analyzed by the Soil and Water Assessment Tool (SWAT).Under the climate change only scenario,monthly distribution and projected variation of TSS are expected to follow a patt similar to streamflow.Nutrients are influenced both by flow and management practices.The variation of Total Nitrogen (TN) and Total Phosphorous (TP) generally follow the flow trend as well.No evident difference in the N:P ratio was projected.Under the LULC change only scenario,TN was projected to decrease,mainly due to the shrinkage of croplands.TP will increase in fall and winter.The N:P ratio shows a strong decreasing potential.Under the combined change scenario,LULC and climate change effect were considered simultaneously.Results indicate that if future loadings are expected to increase/decrease under any individual scenario,then the combined change will intensify that trend.Conversely,if their effects are in opposite directions,an offsetting effect occurs.Science-based management practices are needed to reduce nutrient loadings to the Bay.