中文摘要：

以陕西省关中平原为研究区域,选取2003—2013年3—5月的Aqua-MODIS遥感数据、降水量和土壤含水量数据,探究10 d、16 d、32 d和48 d时间尺度条件植被温度指数（VTCI）干旱监测方法的适用性。结果表明：随着时间尺度增大,VTCI与降水量和土壤含水量的相关性均逐渐减小,说明VTCI干旱监测方法的适用性随时间尺度的增大而减小,且48 d时间尺度VTCI不适用于监测某一地区的受旱程度。不同时间尺度VTCI干旱监测结果的对比分析表明,旬尺度VTCI干旱监测的准确性最高。

英文摘要：

Drought as a high incidence of agrometeorological disasters,long plagued industrial and agricultural production in many countries around the world. Drought is a natural disaster which has a great impact on human society and natural environment. With the development of economic and the continuous growth of population,range of drought is expanding and increasing. Monitoring and early warning of drought has become the focus of global concern. Vegetation Temperature Condition Index（ VTCI） which integrates NDVI and LST can be applied to monitor current droughts more accurately at regional level,and provides the scientific basis for drought monitoring and crop yield estimation. The Aqua-MODIS remotely sensed data,precipitation and soil moisture from March to May in years from 2003 to 2013 were used to study applicability of VTCI drought monitoring method in the Guanzhong Plain of Shaanxi Province at time scales of 10,16,32 and 48 days. After comparing and analyzing the correlation coefficients between VTCI and cumulative precipitation and soil moisture,it is obvious that the correlation coefficients decrease with the increase of time scales,which indicates the applicability of VTCI drought monitoring method becomes worse with the increase of time scales. The VTCI drought monitoring method at the scale of 10 days is more suitable,while the method at the scale of 48 days is not suitable for monitoring droughts. The VTCI drought monitoring results at different time scales show that the method at the scale of 10 days is more accurate and practical. In order to meet the needs of different time scale agricultural drought monitoring,based on the drought monitoring results at the scale of 10 days,the time scale transformation method is applied to research and develop the drought monitoring method of main growth period for corps,which is one of the important research direction in the future.