基于多源遥感数据的农业干旱监测模型构建及应用

干旱监测问题是干旱灾害模拟与预警及旱灾防灾减灾的关键。基于2001-2013年淮河流域40个气象站资料、28个土壤墒情站点和中分辨率成像光谱仪（MODIS）多源遥感数据，采用SEN趋势法和标准化降水蒸散指数（SPEI）等方法，综合了大气-植被-土壤相互作用等多元成因，构建了适用于淮河流域多源综合遥感干旱监测模型，探讨淮河流域干旱时空规律。研究表明：（1）基于多源数据构建综合干旱监测模型，利用土壤墒情和典型年份干旱监测对综合干旱监测模型适用性进行评价，通过了P < 0.01的显著性检验，构建的模型可综合反映出农业和气象干旱多源信息；（2）淮河流域干旱面积和干旱频率大都集中在4-5月和7-9月，9月份受旱面积最大。河南省是淮河流域受旱频率最高，其干旱面积占淮河流域多年平均干旱面积比重最大（38%），其次是安徽（22%），旱地受旱面积比重大于水田受旱面积比重；（3）淮河流域2、3和5月干旱有显著减弱趋势；而1、4和6月则有增强趋势。淮河流域小麦灌浆-成熟时期（4-6月）缺水对小麦粮食产量影响显著，综合淮河流域干旱趋势变化，需强化淮河流域4月份小麦的干旱监测与旱灾预警。

An integrated agricultural drought monitoring model based on multi-source remote sensing data: model development and application

Drought monitoring is crucial for the early warning of drought hazards. In this study, an attempt to develop an Integrated Remote Sensing Drought Monitoring Index (IRSDI) was made, based on multi-source remote sensing data, with the aim of investigating drought conditions across the Huai River basin in both space and time. The IRSDI relied on:meteorological data recorded from 2003 to 2013 at 40 stations, soil moisture data recorded at 16 stations, Moderate Resolution Imaging Spectroradiometer (MODIS) data obtained by linear trend detection, and on the Standardized Precipitation Evapotranspiration Index (SPEI). The results of this study indicate that:(1) the proposed IRSDI is able to describe and monitor drought conditions well in both space and time; (2) droughts and high drought frequency occur in the periods April-May and July-September. In particular, September is the month during which the largest area is dominated by droughts. In particular, droughts affect Henan province, which accounts for 38% of the total drainage area of the Huai River basin, followed by Anhui province, which accounts for 22% of the total drainage area of the Huai River basin; (3) droughts tend to decrease during February, March and May, whereas they increase during January, April and June. Wheat grouting and ripening occur in the period from April to June. Thus, droughts in these months can seriously affect wheat production, and a more careful allocation of water resources and irrigation management should be performed during this period. Nevertheless, spring droughts and autumn-winter droughts should receive proper attention as well, in order to manage and reduce drought-induced losses.