Quantitative Evaluation And Risk Analysis Of Water-Carrying Capacity In Beijing And Its Management Counter-Measures

Water is the basic resource which can keep the integrated ecological system, human existing and socioeconomic development, howere, a number of areas around the world are facing water problems with different leavels, along with the population increasing manufacture expanding and the speeding up of urbanization process. Beijing has long been one of the super major city witch is the most seriously shortage of the water resource all over the world. Per capita consumption of the water resource is just 1/6 of the entire country, and it is 1/25 of the munber all over the world. Having a systematically research to the bearing capacity of beijing water resource contains very important means of theory and reality.This passage, which firstly brought up the connection of water resourse's bearing capacity, property and influencing factor, it thinks that water resourse's bearing capacity is a kind of the biggest and coordinated developed social economy scale which the area water resource can support under certain technical economy condition and on the premise of meeting the needs of living water. And then, comprehensive analysis the advantages and disadvantages of some comman ways on researching water resourse's bearing capacity in and abroad at the present time, pointed out that the multi-target analysis is a comparatively suitable way dealing with society-economy-resources-environmental system this kind of complicated , multiattributed, multi-target groups decision problem. And also is the trend of present water resources management.After that, this passage collected and arranged a great amount of the related data about beijing water resource, arrive at the following conclusion: Beijing available water quantityduring these years, when the guarantee rate are 50%,75%,95%, respectively are 46.84,39.66,32.92 hundred millions cubic meters, however, the yearly water consumption is 38.8 hundred millions cubic meters, the water resource supply and demand contradiction is terribly sharp! For this reason, build up the water resource multi-target analysis model, divide the city water resourse's bearing capacity system into the following five subsystems, to determine five optimize target: GDP(gross domestic product, reflects the expanding of economy), COD(Chemical Oxygen Demand, feflects polluting condition), Food(grain yield, reflects agricultural industry and social steady), TWP(urban occupied population, reflects the aggregative indicator of economic and social development), and WE(entironment water needs, reflects living environment quality), these five targets can fully reflect the water resource carrying capacity on economy, society population and so on. Because of the principal factors that influence each target are closely linked, and there are relationships of dependence and restrict between each others, so it is impossible going after single target's development, we just can seek to the unitary relative optimum. It figures out that 50% of the yearly holistic degree of satisfaction reached 0.725, the top satisfied among these is GDP, the lowest is WE. The final optimize resault, GDP is 4626.95 hundred million yuan, urban COD discharge amount is 166. 7 thousand ton, urban popedom Food is 2420 thousand ton, TWP is 8132.2 thousand, WE is 12.02 hundred million ton.In the end, the passage fathomed on the shortage of beijing water resource from the point of risk management. According to the analysis of water resource risk's connotation, define the risk degree, reliability, continuing stability index, restorability estimate, integrated lossing degree index, use these indexes to take quantitative analysis about the shortage of beijing water resource: the beijing average risk index r is 0.75, the system is facing a biggish risk; the continue stabilityωis 0, it shows that on the premise of the safty of water resource, in the coming year the probability of system is still be safe is impossible, it fully proved the risk of beijing's seriously shortage of water resource; and the recoverability indexβis 0.125, implies sometimes the system is in a state of unsafe, it's a little bit difficult to return back to safe state; the entirety lossing indexμ' is 0.036, it indicates this area'srisk rate is 3. 6% made by the shortage of water resource, the shortage of water resource is seriously risk. And thereout pointed out the countermeasure and suggestion on carrying out the water resource's sustainable development.