Comparative Analysis Of Different Remote Sensing Methods For Retrieving Soil Moisture

Soil moisture is one of essential parameters in the study of climatology, hydrology, ecology and agriculture, which dominates the transportation and balance of water and heat between lands and air directly. Compared with traditional soil moisture measurement methods, remote sensing technology can obtain the information for the change of land soil moisture at regional and large-scale.Therefore, it can have be applied in many fields such as land hydrology, flooding and drought, agricultural production, and ecology.Many researchers have focused on retrieving soil moisture using remote sensing technology, meanwhile, proposed a few methods, which can be applied praticallly and effectively. However, few works have been done to compare and analysis different methods. This study was aimed to conduct and compare various remote sensing approach from Shendong Mining area, which were thermal inertia method, temperature vegetation drought index (TVDI) method and passive microwave method. The MODIS16days data with1km resolution was used to generate TDVI and ATI. The AMSR-E data with10km resolution was used in passive microwave method. The results indicated that:①Comparing other methods, thermal inertia method can produce the relatively higher accuracy at reginonal scale, however, thermal inertia method was only effective in bare soil or a low vegetation coverage area.NDVI<0.33can be used as a suitable condition of method for retrieving soil moisture in the depth of10cm;②As TVDI method can be coverd the whole vegetation cover area, thus, combining with ATI and TVDI method would overcome the limitations which resulted from using a single method;③Passive microwave method can be used to retrieve soil moisture of the research area, and the inversion accuracy of soil moisture value in the depth of10cm was higher than that in the depth of0～5cm;④There was some limitations to retriveve soil mostrue by using a single method such as thermal inertia method. Furthermore, this research provided a meaningful and sound way to retrieve soil moisture with high accruacy using different remote sensing methods.