| Sichuan is a Area with complex topographic and climatic conditions, the natural calamity takes place constantly in the area, leading to drought with wide area, long duration and high intensity, it will cause great influence on people’s living and ecological environment. In recent years, affected by the drought in Sichuan has been increasing year by year. Therefore, a effective and feasible of method for drought monitoring in Sichuan is necessary, that is meaningful aimed at the sustainable development of society, economy and environment.At present, many methods for drought monitoring by remote sensing data were applied at home and abroad. Satellite remote sensing data has been widely used in drought monitoring, including TRMM precipitation data, TM data, MODIS data, as well as the environment of small satellite and FY satellite data of the Domestic; The method of drought monitoring in the Visible, near infrared, thermal infrared and microwave remote sensing monitoring can suitable for the regional widely, such as temperature vegetation index of drought monitoring was applied in Sichuan usually. But its application is limited due to the cloudy weather of humid climatic characteristics and complex topographic, combined with the differences surface cover of vertical zonality.Taking the increasingly serious summer drought as point of the study. Considering the difference of complex topographic and climatic, combined with the view of Vegetation Cover, Land Surface Temperature and precipitation of the agricultural drought occurrence and development, making full use of multisource remote sensing data that was MODIS, TRMM and DEM, model construction of SDCI was based on Vegetation Cover, Land Surface Temperature and Precipitation, and a correlation analysis was made between the conventional model of drought monitoring and SDCI,determining the most suitable weight combination of SDCI. Verification and Analysis of the monitoring results with drought frequency and soil moisture in the study area, then divided summer drought level of SDCI.The results show that Sichuan with great disparity in topography, looks like thediversity in vegetation types and climate, Divison of topography regions in Sichuan according to the differences of varied topography and climate, including the east of Sichuan Basin, southwest mountainous and West Sichuan Plateau area. The maximum summer drought frequency are about 66% in the east of Sichuan Basin area, which distributed in most areas of basin, that were located in southeast of Nanchong and Bazhong, northeast of Daxian, especially in northwest part of Mianyang and Deyang,southeast of Zigong, Yibin, Luzhou; The maximum summer drought frequency of the transition region is about 35%, drought occurred in the southwest mountainous of Sichuan easily, the southern and southwestern of Panzhihua and Xichang is especially outstanding; Covered by glaciers and snow Seasonal and permanent has a great effect on drought monitoring of West Sichuan Plateau area, so the frequency is mainly distributed in the southern and southwestern about 20%, that in the southeastern and southeastern part of Kangding was low. Such summer drought frequently occurs from mid-August to mid-September in 2000, 2002, 2003, 2005, 2006, 2007, 2009, 2011 and2013, which is widely distributed in the east of Sichuan Basin, although summer drought occurs frequently, but it is not serious in 6-8 month. |
PDF Full Text Request