基于多源干旱指数的黄淮海平原干旱监测

黄淮海平原是我国重要的粮食基地,由于季风、气候等的影响,干旱频发,严重影响了粮食生产,实时监测黄淮海平原的干旱情况,对于合理制定农业政策、指导农业生产具有重要意义。基于MODIS反射率产品、温度产品和气象站点降雨数据等,采用改进归一化水指数(MNDWI)、植被健康指数(VHI)和标准化降水指数(SPI),对黄淮海平原2001~2012年干旱情况进行监测,分析其空间、季节、年际变化规律及其潜在原因,并根据结果确定3个指数的使用条件。结果发现:黄淮海平原燕山山麓和太行山山麓受西伯利亚冬季风的影响,同时由于春天植被覆盖少,水份蒸发较快,易发生春旱;农作物区在海拔25~100m之间比其他地区要干旱;12年间2003年干旱最弱。所采用遥感指数由于对水分温度敏感适用于实时监测,而气象指数SPI适用于长时间序列的干旱变化监测,亦可用于干旱预测。

Drought Monitoring in Huang\|Huai\|Hai Plain Using the Multi\|drought Indices

With the influence of the monsoon and climate,high frequent droughts have heavy effect on the grain production in Huang\|Huai\|Hai Plain,which is one of the most important grain base in China.So it is significant to real\|timely monitor drought conditions in this plain for the improvement of our grain yields.Based on MODIS reflectance,land cover products,and rainfall over the weather stations in the study area,the Modified Normalized Difference Water Index(MNDWI),Vegetation Health Index (VHI) and standardized precipitation index (SPI) were adopted to monitor drought conditions from 2001 to 2012.This paper analyzed the temporal and spatial variations and their underlying reasons.The results indicated that VHI had a coincident variation with MNDWI,Winter monsoon from Siberian,spring vegetation and fast water evaporation influenced significantly spring drought over the Huang\|Huai\|Hai plain,especially for Yanshan and Taihang piedmont.Crop were planted from 25 to 100m height above sea level which is more sensitive to dought than others;the weakest drought was happened in 2003.MNDWI and VHI are sensitive to vegetation moisture and land surface temperature,and can be used to monitor drought in real time.While SPI is suitable for drought monitoring or forecasting over a long time series.