Multiple spatial scale watershed runoff and sediment yielding prediction method and device

Abstract

The invention provides a multiple spatial scale watershed runoff and sediment yielding prediction method and device. The method comprises the steps that according to DEM topographic data, remote sensing images and a river network of a watershed to be predicted, the watershed to be predicted is divided into m three-level ditches; according to the runoff yielding at the fracture surface outlet of each three-level ditch, the confluence amount of a drain net of each two-level ditch is calculated by using a nahi instantaneous unit line; furthermore, a Muskingum multi-reach continuous flow routing model is used for calculating the runoff yielding at the fracture surface outlet of the watershed to be predicted; according to the sediment yielding of the gully slope geomorphologic units, ravine slope geomorphic units and groove geomorphic units in the three-level ditches, the sediment yielding of the three-level ditches is determined; and furthermore, the sediment delivery ratio is used for determining the sediment yielding at the fracture surface outlet of the watershed to be predicted. Through model coupling calculation, the multiple spatial scale watershed runoff and sediment yielding prediction method can simulate and predict multi-spatial scale watershed, and the accuracy and promotion practicability of soil erosion sediment yielding simulation and prediction are improved.

Description

Technical field [0001] The invention relates to the field of distributed runoff and sediment yield prediction technology, in particular to a method and device for predicting runoff and sediment yield in a multi-space-scale watershed. Background technique [0002] The current watershed flood cement and sediment forecast model mainly uses a single type of model, combined with rainfall observation data and underlying surface data, to simulate and predict runoff and sediment production. However, because hydrological phenomena show different characteristics at different time and space scales, they are different. The spatial variability of hydrological variables and parameters on different scales is very large, and the key issues of the mechanism of water-sediment cycle at different spatial scales, and the key issues of dynamic coupling simulation of all-element process of water-sediment cycle in the basin have not been resolved. Therefore, a single-type model is in progress. When simu...

AI Technical Summary

Problems solved by technology

[0002] The current flood and sediment forecast models in the river basin mainly use a single type of model, combined with rainfall observation data and underlying surface data, to simulate and predict runoff and sediment production. The spatial variability of hydrological variables and parameters on the scale is very large, and the existing key problems of the mechanism of water-sediment cycle on different spatial scales and the dynamic coupling simulation of the whole element process of water-sediment cycle in the watershed have not been solved. In the process of simulating the water and sediment process in the watershed, there are problems that the scope of the watershed is limited and it is difficult to promote it on a large scale

Images