Abstract: What disclosed are a surface water monitoring method and apparatus, a computer device, and a storage medium. The method includes: obtaining optical satellite images and synthetic aperture radar satellite images of an area to be monitored in a preset time period; determining a first target region in each optical satellite image, determining a water body type of a pixel in a second target region in the SAR satellite image corresponding to the first target region; determining water body types of pixels in other regions in the optical satellite image, the other regions being regions in the optical satellite image other than the first target region; and determining surface water distribution information of the area to be monitored in the preset time period according to the water body type of the pixel in the second target region and the water body types of the pixels in the other regions.

Abstract: A retrieval method and a retrieval apparatus for reservoir water storage. The retrieval method includes the following steps. A synthetic aperture radar (SAR) image sequence of a target local waters in a target reservoir is acquired. A water area sequence of the target local waters is determined according to the SAR image sequence. A first relationship between a water level of the target reservoir and a water area of the target local waters of the target reservoir is obtained. The water area sequence is converted into a target water level sequence according to the first relationship. And a water storage sequence of the target reservoir is obtained according to a water level-water storage relationship curve and the target water level sequence.

Abstract: Disclosed are a monitoring method and a monitoring device for irrigation water use (IWU), a computer device and a non-transitory computer readable medium. The method includes: determining a linear correlation between a first evapotranspiration (ET), a first soil water storage, and a monthly reference ET of a target region according to a first data set in response to a monitoring instruction from a user; determining multiple second soil water storages of the target region based on a second data set, and the linear correlation of the first ET, the first soil water storage, and the monthly reference ET of the target region; determining the IWU of the target region according to the first ET, the second ET, the first soil water storage, the second soil water storage of the target region, and the first preset correlation.

Abstract: Disclosed are a runoff estimating method and a runoff estimating device for an ungauged region. The method includes: acquiring driving data, the driving data comprising monthly-scale precipitation, monthly-scale potential evapotranspiration, and soil water volume content of a basin within a preset period; establishing an objective function of monthly-scale water quantity balance change of the basin, and determining a parameter to be calculated in the objective function; initializing the parameter to obtain an initial value of the parameter; inputting the initial value of the parameter and the driving data into the objective function to obtain an initial function value of the objective function; performing an iterative computation on the parameter based on the initial value of the parameter and the initial function value to obtain an optimized value of the parameter, and inputting the optimized value of the parameter into the objective function to obtain an objective function value.

Abstract: The present disclosure relates to a method and a device for monitoring the water volume change, and a computer device and a storage medium. The method includes: acquiring a lake shoreline change sequence, a lake area change sequence, and a combined altimetry water level sequence; obtaining a lake water level sequence based on the combined altimetry water level sequence and the lake shoreline change sequence; calculating a first regressive relationship between the lake water volume and the lake water level based on the lake area change sequence and the lake water level sequence; and obtaining a lake water volume change sequence based on the lake water level sequence and the first regressive relationship between the lake water volume and the lake water level.

Abstract: The present disclosure relates to a method and a device for simulating discharge, and a computer device. The method includes steps of: acquiring forcing data; simulating the discharge of a river basin to be measured according to the forcing data and a calibrated hydrological model of the river basin, to obtain a simulated discharge of the river basin; the calibrated hydrological model is a hydrological model including calibrated model parameters; the calibrated model parameters are obtained by calibrating model parameters of an initial hydrological model, according to a converted discharge of the river basin to be measured and the GRACE-derived total water storage changes of the river basin to be measured.

Abstract: The present disclosure relates to a method and a device for simulating discharge, and a computer device. The method includes steps of: acquiring forcing data; simulating the discharge of a river basin to be measured according to the forcing data and a calibrated hydrological model of the river basin, to obtain a simulated discharge of the river basin; the calibrated hydrological model is a hydrological model including calibrated model parameters; the calibrated model parameters are obtained by calibrating model parameters of an initial hydrological model, according to a converted discharge of the river basin to be measured and the GRACE-derived total water storage changes of the river basin to be measured.

Abstract: The present disclosure relates to a method and a device for monitoring the water volume change, and a computer device and a storage medium. The method includes: acquiring a lake shoreline change sequence, a lake area change sequence, and a combined altimetry water level sequence; obtaining a lake water level sequence based on the combined altimetry water level sequence and the lake shoreline change sequence; calculating a first regressive relationship between the lake water volume and the lake water level based on the lake area change sequence and the lake water level sequence; and obtaining a lake water volume change sequence based on the lake water level sequence and the first regressive relationship between the lake water volume and the lake water level.