Study On Soil Moisture Inversion Based On MODIS And TM Images

Soil moisture is the water condition of soil, it is an important indicator parameter of hydrology, meteorology and the agricultural science, the research about Soil moisture has extremely vital significance for the climate agricultural,and drought monitoring. With the development of remote sensing technology, it comes true that getting the soil moisture quickly and widely, the shortcomings of traditional methods in monitoring soil moisture is overcame.In this paper, the methods of soil moisture monitoring based on MODIS and Landsat TM data which has been widely applied was researched, under the goal of complementary advantages with multi-source remote sensing image data, the method of applying both Apparent thermal inertia and Vegetation supply water index in soil moisture monitoring based on MODIS and TM data was put forward. The results show that the dependence of ground measured data was reduced, the spatial scales of soil moisture could be increased, the accuracy of soil moisture under different vegetation coverage surface was improved. The main research work and results are as follows:(1)On the basis of collecting remote sensing inversion data, the Apparent thermal inertia method which is suitable for soil/low vegetation coverage area and the Vegetation supply water Index method that is suitable for high vegetation coverage area was selected, the research about monitoring soil moisture based on Apparent thermal inertia with MODIS data, based on Vegetation supply water Index with MODIS data,and based on Vegetation supply water Index with TM data were make.(2) The feasibility to achieve complementary advantages for monitoring soil moisture with MODIS and TM data was analyzed, using Normalized Difference Vegetation Index (NDVI) to distinguish between land cover types, the research on the application of monitoring soil moisture applying both the Apparent thermal inertia and Vegetation supply water Index was made.(3)Taking Baisha Irrigation of Henan province as experimental area, established the soil moisture monitoring system in the VS2005development environment, using the object-oriented C#language based on ArcGIS and ENVI/IDL secondary platform.The system can realized that monitoring soil moisture applied Apparent thermal inertia and Vegetation supply water Index with MODIS image data, monitoring soil moisture applied Vegetation supply water Index with TM data, monitoring soil moisture applied both MODIS and TM data, and the system can output the intermediate parameters in remote sensing inversion process,output the thematic map of soil moisture monitoring results.(4) The results from the method applied MODIS and TM with the results from single image and model was compared, the results show that the method applying multi-source remote sensing can get a high accuracy in soil-vegetation mixed terrain.