Research To Crop Growth Monitoring Indicators With Remote Sensing

Crop growth monitoring could provide crop state information for the decision-maker, as well as reflect variety information of crop yield in time. The index of crop growth monitoring have closely relation with crop yield, it could forecast large-scale food state that possibility missing or surplus as early as possible, it is important for the macro control of food. Although it has been studied for more than twenty years, the following flaws can be found in almost all the research on crop growth monitoring methods based on remote sensing:(1) NDVI is too much used while other indices such as LAI, NPP, TCI, VCI and NDWI are seldom used;(2)The monitoring of crop growth is disjoined with crop yield, while they should be studied together;(3) The influences of phenology are not ignored, while different indices should be used on different phenologies(4) The crop growth from remote sensing is disjoined with traditional observed crop growth.Taken the main food crops as monitoring target the paper the. studied the suitability and validity of six remote sensing indices in different zones, for different crops and at different phenologies both in real-time monitoring and crop growing process monitoring. The six remote sensing indices used in the study are NDVI, LAI, NPP, TCI, VCI and NDWI. The country scale index collection for crop growth monitoring with remote sensing were build after research.The main content and conclusions are as following:(1)Derivation of country-wide crop LAI and NPPAfter analyzing the relationship between observed LAI and NDVI in four representative observing areas in China, we built LAI estimating model for each of these areas. The nation-scale crop LAI estimating model is derived by extrapolating the four models with zone data, which divide the whole country into 44 zones...