The invention discloses a wheat field grain
water content prediction method and
system based on a PlanetScope image. The method comprises the following steps: acquiring 8-waveband multispectral surface reflectance data of PlanetScope, screening an image of which the
cloud cover is lower than a preset percentage from the 8-waveband multispectral surface reflectance data, and calculating an
enhanced vegetation index (EVI) pixel by pixel to obtain an EVI
time sequence; obtaining the heading period of the
winter wheat based on the preprocessed EVI
time sequence; based on the heading period of the
winter wheat, predicting the physiological mature period of the
winter wheat through an effective accumulated temperature accumulation model; an actually measured
wheat grain moisture content sample is obtained, and a field
grain drying model combining a
moisture diffusion mechanism, saturation
vapor pressure difference adjustment and
Gaussian function constraint is constructed based on the
wheat grain moisture content sample; and by taking the predicted physiological mature period as a priori and combining daily meteorological data and a field
grain drying model, simulating the dynamic change of the moisture content of the wheat grains day by day, and generating a
spatial distribution diagram of the moisture content of the wheat grains. The method can predict the
water content of the wheat grains in the field in a high-time-efficiency and high-precision manner.