基于SWAT模型的诺敏河流域径流对土地利用/覆被变化的响应模拟研究

土地利用/覆被变化直接反映了人类活动的影响程度,对于流域水文循环过程影响显著。本文以诺敏河流域为研究区,基于1976和2000年两期土地利用数据,结合SWAT模型定量评价了径流对土地利用/覆被变化的响应。研究结果表明:SWAT模型可以较好地模拟诺敏河流域的月径流变化过程,在研究区具有一定的适用性;相对于1976年的土地利用条件,2000年土地利用变化主要表现为林地和草地面积减小,耕地面积增加。1976-2000年间诺敏河流域土地利用变化导致年均地表径流增加了17.78%,且空间差异显著,尤其是下游的莫力达瓦达斡尔族自治旗和阿荣旗等地地表径流增加趋势更为明显,增加幅度超过20 mm。模拟研究对于诺敏河流域合理规划土地利用格局具有重要意义。

Response of runoff on land use/cover change in Nuomin river basin based on SWAT model

The land use/cover change (LUCC) directly represents the influence degree of human activities, and has quite significant effect on the watershed hydrological cycle.Taking Nuomin River Basin as the study area, the paper quantitatively evaluated the response of runoff on land use/cover change by applying the land use data in 1976 and 2000 and combining with the distributed hydrological model, Soil and Water Assessment Tool (SWAT). The results showed that SWAT model is able to better simulate the monthly flows and has certain applicability in the Nuomin river basin;the land use/cover changes mainly showed the decrease of forestry and grassland,and the increase of farmland in 2000 compared with that in 1976,which led to the increase of 17.78% of average annual surface runoff,which also brought the significant spatial variatio, especially in the downstream of basin including Moridawa Daghur Autonomous Banner and Arong Banne, the increase volume is over 20mm. The study has practical significance for the reasonable plan of land use pattern in Nuomin river basin.