Da Qing Regional Ecological Risk Assessment

Regional ecosystem risk assessment (RERA) is a new methodological system in sciences, which is to meet the need of the socioeconomic sustainable development. Regional ecosystem risk assessment is a process of assessing the probability of adverse ecological effect that has occurred or is occurring at the result of one or many stressor (chemical, physical and biological stressors etc.) to ecological environment. RERA plays an important role in protecting ecological environment, maintaining public health and developing economy. And is the important guarantee to realize the coordination, sustainable and stable development of society, economy and environment. Offers scientific basis for the government making environmental policy.This text evaluates at the general theories frame that follow the foretime ecosystem risk with the method system at the same time, the basis is big to celebrate the special nature in region geography, social economy with the ecosystem environment characteristic, from the sieving with identify each main risk material commence, at big celebrate the region Regional Chinese foot dimension goes forward line Regional ecosystem risk assessment. First, select four kinds of main risks source from bigly celebrate the main risk in region source, namely the flood, drought, sand-dust weather and petroleum pollution accident, etc. According to the different a request for to habitat, study this 19 kinds of landscapes ecosystem type of the Regional induce for 7 kinds of ecosystems system: Then the marsh of bulrush, lakes and reservoirs , salt alkali wasteland, prairie, island form wood, farmland, town. The difference is proceeded by characteristic according to each type ecosystem to the analysis of four kinds of main risks source, including the certain risk all rate, delimiting the space distribute, analyzing the risk strength to the receptor etc. At proceed the revelation the different from endanger to analyze the inside, this text borrows ecosystem index number that this index sign to reflect primarily habitat the ecosystem meaning of the type of habitat the different from position, with weak an index number to show the destructibility of the habitat, from but compute each ecosystem that is lost by ecosystem system an index number. Because each main risk material is function by to the risk the strength is different, also has the difference to the function size of the formation local area ecosystem risk, the for this reason a literary grace uses the level of structure analysis method (AHP) to proceed tosynthesize the evaluation to the main ecosystem risk material, and classify to judge the worth and reasonable calculation in power in preface in row in matrix problem a not the line turns the problem, putting forward the application according to Genetic Algorithm(GA [5]). Proceeding the risk token, then synthesize front two information of stage, to environment the kind of the risk evaluates the process the inside the indetermination problem the proceeding the analysis with strength and risks with describe. Finally, according to divide the line of five the characteristic of class ecosystem risk area, put forward the ecosystem risk management counter plan that aim at each ecosystem risk area respectively.This Regional ecosystem risk assessment in proceeding expose - hazard analysis process, aiming at each risk source to is characteristic by to withdraw with the ecosystem to divided into section the inside to apply the ARC/INFO with the ARCEDIT module to make the analysis for realizing each ecosystem system type belonging to database establishing with characteristic withdrawing, using ARC module piece to analysis ecological index and risk boundary. At each two evolve on behalf generation on behalf behind use the choice zone conduct and actions a choice for evolving acting for zone of the generation on behalf finally, evolve the process use the VB the plait the distance, enhance the efficiency of the Genetic Algorithm.This dissertation purpose is toward the decision maker and governor to provide the research...