摘要
植被供水指数(VSWI)是进行干旱研究的有效指标,是进行区域土壤湿度反演的重要方法。利用MODIS数据,提取归一化植被指数(NDVI)、修正的土壤调整植被指数(MSAVI)、增强型植被指数(EVI)和地表温度(Ts)等参数,建立植被供水指数、基于MSAVI的植被供水指数(VSWI-M)、基于EVI的植被供水指数(VSWI-E),并对比三种指数反演土壤湿度的效果;在此基础上,建立分区域、基于NDVI阈值的混合植被供水指数(MVSWI)模型,利用20 cm土壤墒情实测数据对模型进行检验,RE,RMSE误差结果显示,MVSWI模型具有较好的精度,可以用来估算土壤湿度。
The vegetation supply water index(VSWI)is an efficient index for drought research,and an important method for regional soil moisture retrieval. Parameters of normalized difference vegetation index(NDVI),modified soil-adjusted vegetation index(MSAVI),enhanced vegetation index(EVI)and land surface temperature(Ts)are extracted by using the MODIS data,so as to build the VSWI,MSAVI-based VSWI(VSWI-M)and EVI-based VSWI(VSWI-E). The soil moisture retrieval effects using the three indexes are compared. On this basis,the mixed VSWI(MVSWI)model based on sub-regions and NDVI threshold is built. The actual moisture measured data of 20 cm of soil is used to verify the model. The RE and RMSE results show that the MVSWI model has a good accuracy,which can be used for soil moisture estimation.
作者
杨彦荣
胡国强
YANG Yanrong;HU Guoqiang(Network & Education Technology Center,Northwest A&F University,Yangling 712100,China)
出处
《现代电子技术》
北大核心
2019年第2期138-142,146,共6页
Modern Electronics Technique
基金
国家自然科学基金资助项目(61402375)~~
