塔里木河中上游土地利用变化的径流响应

Hydrological responses to land use change in upper-middle reaches of the Tarim River Basin

为了定量分析塔里木河中上游土地利用变化对径流的影响程度,基于塔里木河流域1980-2015年土地利用数据及相关水文系列资料,利用MIKE SHE分布式水文模型客观模拟评价了流域中上游土地利用变化下的水文响应过程。结果表明:MIKE SHE模型可以较好的模拟塔里木河流域中上游的日流量过程,在研究区具有良好的适用性;1980-2015年间流域土地利用变化导致流域地表日径流量减少了4.2 m^3·s^(-1)。通过仿真模拟分析草地、林地、耕地三种土地利用情景,得到日均流量分别为147.56 m^3·s^(-1)、141.80 m^3·s^(-1),144.72 m^3·s^(-1)由此可见,该流域径流对不同土地利用类型的响应差异较大,产流量的总体趋势为草地>耕地>林地。研究成果对于流域土地利用格局的合理规划及极端水文事件的控制具有重要意义。

Land use/cover change（LUCC）is one of the major driving factors that changethe hydrological processes. Understanding and quantifying their respective influence is of great importance for water resources management and socioeconomic activities,so we apply the widely used MIKE SHE model to the upper and middle reaches of the Tarim River Basin. In this paper,the MIKE SHE model simulates the annual runoff in the Tarim during 2005-2015,and 2005-2010 is the calibration period and 2011-2015 is the validation period. The reliability of the MIKE SHE model was corroborated in terms of the Nash-Sutcliffe efficiency（NSE）and the correlation coefficient（R）. The results confirmed that MIKE SHE was a powerful and accurate model for studying the hydrological change in the Tarim River Basin. The data of the NSE and R in the calibration period were 0.86,0.93 respectively,and 0.83,0.92 in the validation period,respectively. To investigate the impact of LUCC（land use and land cover change）on the stream flow,we firstly use two observed land use maps from 1980 and 2015 that are based on resource and environment science data center of Chinese Academy of Sciences. In the same meteorological condition,and compared with the land use state in 1998,we found that the surface runoff in the Tarim River Basin had a decreasing trend in 2015. In order to further analyze the influence of different land-use scenarios on daily stream flow,we designed three scenarios：grassland,woodland and cultivated land. We found that daily stream flow of grassland scenario was the largest（147.56 m^3· s^（-1））among the three scenarios,while the cultivated land scenario had the medium daily stream flow（144.72 m^3· s^（-1））,and the woodland scenario had the smallest daily stream flow（141.80 m^3· s^（-1））. The research results have important significance for planning the land use and controlling the hydrological extremes.