Research Of Hydrological Responses To Climate Changes And Human Activities In The Kuyehe Watershed Based On SWAT Model

A significant change in the underlying surface caused by large-scale water conservation measures and exploitation of coal mining, resulting in significant changes occurred in the water cycle;while arid and semiarid regions of the water cycle is very sensitive to climate change. In this background, analyzing the response to climate change and human activities in kuye River on the water cycle, in the formulation of sound water management strategies to ensure sustainable social and economic aspects of the river basin development has important significance.Kuye River watershed was the study area in this research, using linear regression,Mann-Kendall nonparametric test methods to analyze the spatial and temporal variation of the current climate of the watershed period; remote sensing image processing, analysis of land use change in the basic characteristics and laws; and then based on SWAT model to simulate the hydrological conditions in the area, quantitative analysis and simulation of the response kuye River runoff on human activity and climate change. It aims to provide a theoretical basis and scientific guidance for the allocation of water resources kuye River.The results of this study were as follows:(1)Climate was warming and drying trend during 1954--2010. The annual mean rainfall of kuye River basin was 402.7 mm the year showed a unimodal distribution curve, July and August account for 50% of the annual precipitation total. Precipitation was insignificant reduction trend, trend rate was-12 mm / 10 a. Mean, maximum and minimum temperatures were average years of 8.4℃, 14.9℃, 1.7℃;mean temperature was a significant upward trend,changes in trend rate was 0.175℃/ 10 a.(2)Significant changes in land use. The main land use types was grassland and arable land, the total area of the basin more than 80%; From 1986 s to 2005 s, grassland, woodland and construction land area were increased, construction and forest have a large increase; while cultivated land, unused land and water area reduction, including the reduction of unused land is large.(3)From 1954 s to 2010 s annual runoff was significantly decreased. Annual mean runoffis 62.3 mm, the uneven distribution of the year, March and August occurs runoff peak.Runoff presented a significant decreasing trend,showed a decreasing trend since 1979, Its abrupt trend occurred in 1995.When 1990 s runoff into the dry season, the run trend rate was-14.6mm / 10 a, and fluctuates significantly between years.(4)SWAT model can better simulate runoff in kuye River. Using the 1954 s to1960s monthly measured data for model calibration, model ENS efficiency coefficient was 0.79, the correlation coefficient R2 was 0.82, relative error Re was-1.6%; Using the 1961 s to1967s measured data to validate the model, ENS, R2, Re,were 0.73,0.93,1.1%,respectively.(5)The dominant reduction factor in runoff is human activity, but the impact of climate change is also very important. In 1957--1985 base period, 1986-2010 the human activities and climate change have led to the reduction in runoff variation, the contribution rate is 68%, 32%,respectively.