Abstract:

Based on the land use data (1986, 1995, 2000 and 2010) and InVEST model, this paper analyzes the land-use change of the middle reaches of Heihe River in the recent 25 years and simulates the water yield of the study area under different land use patterns. Multiple linear regression model is used to explore the influence on the water yield caused by different land use types. The results show that 1) the main types of land use in the middle reaches of Heihe river are bare ground, grass land and farmland. The structure of land use has been changed a lot since 2000. A large number of farmland has transformed into construction land meanwhile water area starts a substantial reduction. 2) 7.3 is considered as the suitable Z value for the study area. From the perspective of subwatershed, the water depth is diminishing from southeast to northwest. 3) The increase of woodland may restrain the water yield. On the contrary, grassland, construction land and bare ground may promote the water yield. Farmland will cause positive or negative hydrological effects due to the different patterns of utility. These results can provide reference for the balance of oasis’ land and water resources.

Key words: land-use change, hydrological effect, InVEST model, middle reaches of Heihe river

摘要：

基于1986, 1995, 2000和2010年土地利用数据和InVEST模型, 研究近25年来黑河中游的土地利用变化规律, 模拟不同土地利用格局下的流域产流量, 并采用多元线性回归模型分析不同用地类型对流域产流的影响。结果表明: 1) 黑河中游主要用地类型为未利用地、草地和耕地, 2000年后土地利用结构变化较大, 大量耕地转化为建设用地; 2) 经过反复检验, 发现当Z=7.3时, 模拟产流量与自然径流量最为接近, 从子流域来看, 产流深度呈现从东南部到西北部逐渐递减的空间分布规律; 3) 林地面积增加抑制流域产流, 而草地、建设用地和未利用地会促进产流, 耕地在不同的利用方式下会产生正负不同的水文效应。研究结果可为实现绿洲水土资源平衡提供借鉴。

关键词: 土地利用变化, 水文效应, InVEST 模型, 黑河中游