Simulation Of Surface Runoff Based On GIS

In this paper, with the technical support of GIS, select Fuling section of the Yangtze River Basin as the study area. Assume that there are three kinds of ground surface:smooth surface, the actual surface and artificial control surface. Based on the Runoff Theory and SCS distributed hydrological model, use DEM, the average annual rainfall of the study area in2009and the land use data as the basic data. Use ArcGIS spatial analysis function of the hydrological analysis module, extract the river network of the study area and divide the sub-basin. And then simulate the average annual runoff of the three different surface of the study area. After that select a sub-basin as the case area, to simulate the time of runoff of the three different surfaces. The result shows that:1) Based on the Runoff Theory and SCS distributed hydrological model, use ArcGIS spatial analysis function of the hydrological analysis module, extract the hydrological information of the study area. And then simulate the average annual runoff and time of the three different surfaces. This way is feasible.2) The result of the average runoff of the study area shows that:the effects of different surface on the surface runoff are obvious. With the surface composition is more and more complex, the surface runoff flow has a decrease trend. The effect of artificial regulation surface is more obviously, especially through improving the ridge height and planting vegetation:the relationship of the average annual runoff between these three surfaces as follow:the smooth surface of the annual average runoff is the more than actual surface, and the actual surface is more than the artificial control surface.3) Seeing from the result of time of three kinds of surface:the effects of different surface on the time of runoff are obvious. With the surface composition is more and more complex, the time of the surface runoff flow has an increase trend. The artificial control surface can reduce the velocity of surface runoff, also can prolong the time. The relationship of the velocity and the time between these three surface as follow:V smooth>V actual>V artificials;T artificial>T actuar>T smooth.