The Study Of GIS-Based Environmental Risk Simulation System

Chemical Industry Park has numerous enterprises and a lot of dangerous sources,Environmental risk accidents occur frequently,but environmental risk emergency management of China exists some problems,such as environmental analysis level is poor,and emergency measures is unsound.In order to reduce environmental risk accident harm to people’s life safety and survival environmen,it’s a top priority that improving the environmental risk assessment of enterprises and enhancing the pertinence and operability of enterprise environmental risk emergency.Prediction of environmental risk is the basis of the environmental risk assessment and results of environmental risk prediction provide the basis for environmental risk contingency plans,environmental risk simulation can also provide the technical means for risk prediction.Taking Qianjiang Economic Development Zone as an example,the environmental risk simulation information system based on GIS has been developed,and leakage accident of the chemical enterprise has been carried on reasonable and credible numerical prediction of risk.Powerful spatial data analysis of Geographic Information System has been made use of simulating the spill’s sphere of influence to the environment,then the results were visualized expressions on the GIS platform.According to software engineering ideas and ArcGIS10.0,the paper carries out the system general design and detailed design.The general design makes the needs analysis,determines the design principles,and discusses the model integration mode.In accordance with the database design scheme,the spatial database and attribute database are created,the spatial data are produced using ArcGIS Desktop software.It makes a map of shapefile format that contains full geographic information of Qianjiang economic development zone,through the processes of format conversion,georeferencing and vectorization.It combines the spatial data and attribute data through the key field,and initially establishes the environmental risk information database based on Geodatabase model.Users can browse,query,update,monitor and manage the related environmental risk information,can also output thematic maps of sensitive target population distribution and risk source distribution through spatial analysis functions,such as the map rendering and buffer analysis,etc.Pollution spill diffusion simulation is carried out based on database.Using the combinated techniques of GIS and environmental models,We finally achieve environment risk simulation studies of the qianjiang economic development zone by data exchange through the files.It can accurate simulation of pollutant diffusion process of space and time at the time of the accident,namely different pollutant concentrations of toxic range(half lethal concentration range,the concentration of the immediate threat to life and health and short contact time allowable concentration range).In summary,this paper constructs the environmental risk simulation information system based on GIS.The system can effectively share information of the environmental risk,and achieve the visualized expressions of the leakage accident influence scope on the GIS platform.It provides decision support for the management department which accurately starts the corresponding level of environmental risk emergency planning,and makes the emergency response quickly.It provides technical reference of combination GIS technology with environmental risk for such ares.