基于HJ 1B遥感数据的冬小麦旱情监测研究

为确定植被干旱指数(TVDI)法在苏北地区冬小麦干旱监测中的适用性,利用HJ-1B星CCD、IRS数据,建立地表温度(Ts)-归一化植被指数(NDVI)特征空间,并提取TVDI,对2012年3月26日宿迁市土壤水分信息进行遥感监测,以地面样点实测数据进行验证,评价了地表温度及植被指数信息对TVDI指数变化的敏感性.结果表明,宿迁市较干旱区域主要集中在市、县的城区附近,较湿润区域主要分布在水体周围;TVDI与土壤湿度的相关性随土层深度增加而降低,其中在10 cm、20 cm深度的相关性达到极显著水平;由于Ts直接影响土壤含水量,而NDVI为间接影响,因此TVDI对Ts的敏感性大于NDVI.基于HJ-1B数据的TVDI指数法对冬小麦干旱具有较好的监测效果.

Study on Drought Monitoring of Wheat by HJ 1B Satellite Images in Northern Jiangsu

Drought is one kind of natural disasters that seriously affects agricultural production in China. In order to determine if the TVDI index could be used in drought monitoring of winter wheat in northern Jiangsu province, CCD and IRS data of HJ1B satellite were used to establish NDVI T_s space and monitor the information of soil moisture in Suqian city on March 26, 2012, validated with ground sample, and the sensitivity of T_s was evaluated with vegetation index information on the TVDI index. The results showed that: the drier areas of Suqian mainly concentrated nearby the urban area, wetter areas are mainly distributed in the waters around; the correlation between TVDI and soil moisture reduced with soil depth increasing, in which the correlation reached extremely significant level with the data in the 10, 20 cm soil levels; T_s directly affected the soil moisture content, and NDVI as indirect effects, therefore, TVDI was sensitive to T_s greater than NDVI. TVDI index method based on the HJ1B data on drought monitoring of winter wheat had good effect.