The present invention is applied to the technical field of river channel
water depth inversion. Disclosed is a river channel
water depth inversion method based on a
water depth-water surface area
mathematical model and
remote sensing, comprising constructing a first water depth-water surface area
mathematical model of a river channel; on the basis of the type of the river channel, calculating a relationship function among the
discharge section area, the water depth and the flow path of the river channel, and a relationship function among the area of triangles on two sides, the water depth and the flow path of the river channel, and substituting the relationship functions into the first water depth-water surface area
mathematical model to obtain a second water depth-water surface area mathematical model; on the basis of the relationship between a
water level and the water depth, converting the second water depth-water surface area mathematical model into a
water level-water surface area mathematical model, in view of a
water level-water surface area relationship obtained by
remote sensing, solving an unknown number in the mathematical model, and substituting the solved number into the second water depth-water surface area mathematical model to obtain a third water depth-water surface area mathematical model; and substituting a water surface area extracted by
remote sensing into the third water depth-water surface area mathematical model to obtain the water depth of the river channel. The present invention improves the representativeness of a water depth value, and also overcomes the difficulty of using bands to invert the water depth of water having high
sediment content.