利用温度植被干旱指数(TVDI)方法反演杭州伏旱期土壤水分  

Reverse of Soil Moisture for Summer Drought Period in Hangzhou by Using TVDI Method

作　　者：范辽生[1] 姜纪红[1] 盛晖[1] 黄晓萍 

机构地区：[1]杭州市气象局,杭州310008 [2]浙江电力实业总公司,杭州310003

出　　处：《中国农业气象》2009年第2期230-234,共5页Chinese Journal of Agrometeorology

基　　金：浙江省科技厅重点项目(2005C23070);杭州市科技局项目(20061133B18);杭州市农业发展基金项目

摘　　要：利用MOD IS资料构建了杭州地表温度(Ts)-增强植被指数(EVI)的特征空间,拟合了特征空间中的干、湿边方程,计算了温度植被干旱指数(TVD I),并推导出利用TVD I和干、湿边土壤水分计算土壤含水量的方程。在计算TVD I的过程中,为了减少高程的影响,利用数字高程模型(DEM)对Ts进行了订正;利用同期野外实测土壤湿度数据计算了干边上的土壤水分值,从而反演杭州2006年伏旱期8月份每隔16d的平均土壤含水量。结果表明:①TVD I方法能反演杭州伏旱期土壤表层水分,实测值与预测值之间平均绝对误差在15个百分点左右。②高程校正后的TVD I能更好的反映土壤水分,与校正前相比,平均绝对误差减少5个百分点,基本满足业务需要。Land surface temperature （Ts） and enhanced vegetation index （EVI） derived from MODIS images were used to create the Ts-EVI space, from which a dryness index-Temperature Vegetation Dryness Index （TVDI） was calculated by the equation of dry and wet line. The soil moisture spatial patterns each sixteen days for summer drought period during 28 July to 28 August of 2006 in Hangzhou were reversed by using the TVDI and the soil moisture of the dry line calculated by using the field measurement data. The results showed that the TVDI method could be used to predict the soil surface moisture and the mean absolute error of the simulation results with the observed soil moisture were with 15%. The modified TVDI by elevation on Ts by referring to DEM could be better used to predict the soil moisture and the mean absolute error was reduced by 5% , compared to the soil moisture without modification.

关 键 词：TVDI 土壤水分 MODIS 

分 类 号：S423[农业科学—植物保护]