【摘要】 以衢江流域作为研究对象,收集流域植被、气候、土壤、水文和地图资料,基于ArcGIS 10.3平台建立了衢江流域SWAT(Soil and Water Assessment Tool)模型。结果表明:率定期和验证期模拟月径流与实测值的相关系数(R2)大于0.83,纳什系数(Ens)大于0.69,模型可以较好地模拟衢江流域径流过程。2000—2015年衢江流域土地利用类型均以林地和农地为主,二者约占流域总面积的98%,其他土地利用类型面积合计不足2%;研究时段内,建设用地面积大幅增加,其他土地利用类型变幅较小。2000年、2005年、2010年、2015年四期土地利用情景下月径流过程变化趋势基本一致,2015年径流量比2000年增加0.27%,水量平衡各分量在四期土地利用情景下差值为1.1～3.8mm。不同情景模拟分析发现,流域内草地面积较小,草地转化为林地对地表径流和水量平衡的影响较小,而农地全部转化为林地,地表径流比当前土地利用模式减少15.0%,同时深层水分渗漏增加5.7%。因此,2000—2015年土地利用方式的微小变化不会显著影响衢江流域径流和水量平衡,研究区林地面积持续增加,将进一步减少地表径流,增加深层水分渗漏,补给地下水。更多还原

【Abstract】 This study selected Qujiang Basin as the site.Some data of vegetation,climate,soil,hydrology and map in this basin were collected,and SWAT(Soil and Water Assessment Tool)model of Qujiang Basin was established based on ArcGIS 10.3.The results showed that the simulated monthly runoff values of calibration and validation periods were good in accordance with actual values in Qujiang Basin,the correlation coefficient of the simulated and the measured values was great than 0.83 and the Nash coefficient(Ens)was greater than 0.69;from 2000 to 2015,forestland and farmland were the main land use types in Qujiang Basin,which accounted for about 98% of the total area of the basin,and the other land use types were less than2%;during the study period,the area of construction land significantly increased,and the other land use types less changed;the trend of monthly runoff variation was similar for land use scenarios of 2000,2005,2010 and 2015;the annual runoff in 2015 increased by 0.27% compared with 2000,and the difference in water balance components varied from 1.1 mm to 3.8 mm in the four phases of land use scenarios;the simulated different scenarios found that the area of grassland in the basin was small,and the conversion of grassland to forestland had little impact on surface runoff and water balance.After farmland was converted to forestland,and the surface runoff was reduced by 15.0%compared to the current land use model,and deep water leakage increased by 5.7%.Therefore,minor changes in land use patterns during 2000—2015 would not significantly affect the runoff and water balance in the Qujiang Basin.The increase in forest area in thestudy area will further reduce surface runoff,and increase deep percolation,and recharge groundwater.更多还原