几种干旱监测模型在宁夏的对比应用

利用MODIS资料和地面自动气象站观测数据反演地表温度（LST），结合MODIS-EVI试验研究改进型温植被旱情指数（MTVDI）。用通道2和LST试验研究改进型能量指数（MEI），用通道1和通道2，引入植被覆盖度，试验研究改进型垂直干旱指数（MPDI）。结合农业气象常规业务地面取土测墒资料，建立各指数与土壤含水率的统计函数关系，均通过0.01显著性检验。将所建模型用于宁夏干旱监测业务，结果表明：MTVDI、MPDI在作物生长季监测效果显著，MEI、PDI对裸露或稀疏植被地表旱情监测比较有效。几个模型各有优劣，综合运用才能在实际监测业务中发挥最佳效果，精度可达90%左右。

Comparison and application of several drought monitoring models in Ningxia, China

Land surface temperature (LST) was obtained by MODIS data and observation data from automatic weather station on the ground. Modify temperature-vegetation dryness index (MTVDI) was studied by LST combined with MODIS-EVI. Modified energy index (MEI) was studied by channel 2 data and LST test. Vegetation coverage was introduced, and modify perpendicular drought index (MPDI) was studied by channel 1 and channel 2 data. Combined with the soil moisture data from the agro-meteorological regular observation business, statistical functions of the indexes and soil moisture were established, which were all pass the 0.01 significance test. The models had been applied to Ningxia drought monitoring business, the results showed that the monitoring effects of MTVDI and MPDI were significant in crop growing season, and MEI, PDI were effective on bare ground or sparse vegetation. Each model has its own advantage and disadvantage, and the comprehensive application of the models could achieve the best results during the actual monitoring. The accuracy could reach to 90%.