基于宇宙射线系统的土壤水分地面真值获取与尺度扩展方法研究

遥感土壤水分真实性检验是提高遥感反演产品精度、提升其应用水平的重要保障。但对于低分辨率、异质性地表下的被动微波遥感土壤水分的真实性检验长期以来面临像元尺度地面真值的获取和尺度扩展方法的挑战。本项目拟依托宇宙射线土壤水分观测系统和无线传感器网络，开展不同下垫面条件下土壤水分“地面真值”的获取、空间异质性分析、尺度扩展方法评估与优化、真实性检验不确定性的评价等研究，分析土壤水分异质性对面土壤水分“真值”获取的影响，进行不同下垫面、覆盖度状况下土壤水分尺度扩展方法的优化和组合研究，并在此基础上获取微波像元尺度土壤水分地面“真值”，为遥感反演土壤水分地面验证提供数据。

Soil moisture remote sensing product validation plays a vital role to improve the accuracy of products and promote the application scope and level. However, the validation of remote sensing soil moisture products under low resolution and heterogeneous land surface faced challenges on estimation of "ground-truth" at the satellite pixel scale and upscaling. Based on soil moisture observation by Cosmic-ray Monitoring System and Wireless Sensor Network, this project aims at analysis of spatial heterogeneity, estimation of soil moisture "ground-truth", optimization and evaluation on upscaling theory and methods, evaluation of uncertainty from the validation process. To achieve these goals, the research will carry out research on soil moiture spatial heterogeneity’s impact on “ground truth” measurement, soil moisture upscaling methods comparison and optimization under different land covers, and then obtain the soil moisture ground truth at the pixel scale to support the validation on soil moisture remote sensing products.