Development Of Zhalong Wetland Flood Routing Simulation Module Based On GIS Technology

In recent years the new-style method of preventing flood and reducing natural disaster is to manage flood disaster risk and to adjust the relation between people and water. The main goal of renovation in rivers is converted gradually into reducing natural disaster, water resources utilization and improving ecological environment. To make good use of flood resources, the whole course including the origin, development, movement and behavior of flood should be studied at first, the movement rule of the flood should be studied, the behavior of the flood should be mastered, and the study of flood must be enhanced to the simulation. Therefore the rapid, accurate, obvious and effective prediction method for flood occurrence time, place, range and intensity can be offered, thus the decision support for utilization of flood resources can be provided.Through the analysis of research object and visualization requirement, combining the basic situation of current research area Zhalong wetland, the research of three-dimension terrain simulation and visualization study of flood routing simulation are developed, and detailed realization method is established. On the basis of GIS technology, the wetland flood routing simulation module is established with object oriented program language of Visual C++, under OpenGL program environment. It provides an operating and analyzing visualization environment for three-dimension terrain simulation and flood routing simulation. Contour lines and elevation points are obtained by vectorization as basic data, which can be used to build three-dimension terrain. TM image and DEM are combined using texture mapping technology, thus realizes monitoring the hydrological change of wetland dynamically. Applying seed spread algorithm in the realization of flood routing simulation, different status of flood routing can be watched by changing water level, and the calculation method of flood volume is put forward. It should be explained that the realization of flood routing simulation under given water level is an approximate method, but it is useful and convenient, and the submerge area current data (TM image) can be analyzed with it rapidly. It can realize the dynamic monitoring of flood status that has great practical significance in the research of the utilization of flood resources.