The purpose of this paper was to implement ＂Soil and Water Assessment Tool （SWAT）＂ model and Geographic Information System （GIS） to evaluate the impact of land use changes on stream discharge in Nghinh Tuong wat...The purpose of this paper was to implement ＂Soil and Water Assessment Tool （SWAT）＂ model and Geographic Information System （GIS） to evaluate the impact of land use changes on stream discharge in Nghinh Tuong watershed （a brand of Cau River） in Northern Vietnam. The watershed was coverd by 56% forestry land, 30% agricultural land and the remain 14% for others. Stream discharge observed data from 2002 to 2007 were used for calibration period and from 2008 to 2012 for validation period. The result showed that two coefficients （NSE and PBIAS） to evaluate model performance were 0.76 and 6.54% for calibration period and 0.87 and 4.74% for validation period, respectively. Stream discharge strongly depends not only on quantity of precipitation but also on land use change. Through the scenario 1, agricultural land （corn, orchard and tea） increases 9,782.67 ha （2.45%）, meanwhile forest （forest-mixed） decreases 1,091.77 ha （2.75%） as compared to baseline scenario. Additionally, precipitation increases 3.74% in mean wet season, but decreases 0.5% in mean dry season with respect to baseline period. SWAT model was able to simulate stream discharge and sediment yield for Nghinh Tuong watershed successfully not only for baseline scenario but also for scenario 1. In brief, SWAT proves its ability in simulation stream discharge in subwatershed level. It is a useful tool to assist water quantity and quality management process in Nghinh Tuong watershed. This work one more time indicated that SWAT is useful tool for resources and environment management.展开更多
文摘The purpose of this paper was to implement ＂Soil and Water Assessment Tool （SWAT）＂ model and Geographic Information System （GIS） to evaluate the impact of land use changes on stream discharge in Nghinh Tuong watershed （a brand of Cau River） in Northern Vietnam. The watershed was coverd by 56% forestry land, 30% agricultural land and the remain 14% for others. Stream discharge observed data from 2002 to 2007 were used for calibration period and from 2008 to 2012 for validation period. The result showed that two coefficients （NSE and PBIAS） to evaluate model performance were 0.76 and 6.54% for calibration period and 0.87 and 4.74% for validation period, respectively. Stream discharge strongly depends not only on quantity of precipitation but also on land use change. Through the scenario 1, agricultural land （corn, orchard and tea） increases 9,782.67 ha （2.45%）, meanwhile forest （forest-mixed） decreases 1,091.77 ha （2.75%） as compared to baseline scenario. Additionally, precipitation increases 3.74% in mean wet season, but decreases 0.5% in mean dry season with respect to baseline period. SWAT model was able to simulate stream discharge and sediment yield for Nghinh Tuong watershed successfully not only for baseline scenario but also for scenario 1. In brief, SWAT proves its ability in simulation stream discharge in subwatershed level. It is a useful tool to assist water quantity and quality management process in Nghinh Tuong watershed. This work one more time indicated that SWAT is useful tool for resources and environment management.
