Function Evaluation Of The Urban Green Space System With Disaster Prevention And Danger Avoidance

Along with the increase of urban disaster types and the aggravation of disaster frequency, the green space system plays a more and more important part in the urban disaster prevention and danger avoidance. To be more comprehensive and systematic in weighing the function of green space system in the urban disaster prevention and danger avoidance, the article studied the urban green space system from the localization, qualitative and the quantitative angles separately including the function of the urban green space system in disaster prevention and danger avoidance, the green space system with disaster prevention and danger avoidance and the corresponding target and the standard; Constructed the urban green space system with disaster prevention and danger avoidance function evaluating indicator system including 15 criterion level and 47 target level, from the urban overall environment, the city spatial arrangement, the green space system with disaster prevention and danger avoidance, the emergency facility and the emergency capability five aspects,using the analytic hierarchy process and the fuzzy judgment method; Gave a presentation on Changsha overall environment, the spatial structure and the green space system as well as the existence question,especially on the park green space present situation and the index of correlation in detail, including existing total quantity, average per person park green space, layout pattern and service radius and so on,on the basis of investigation in Changsha green space system present situation using the GIS technology to carry on the picture output; Finally, carried on the natural endowments to each factor, through methods as questionnaire and so on, obtains Changsha green space system with disaster prevention and danger avoidance function appraisal is "general".The conclusion is as follows:(1) Establishes comprehensively, system's indicator system structure from the urban overall environment of disaster prevention and danger avoidance, the urban spatial arrangement of disaster prevention and danger avoidance, the green space layout of disaster prevention and danger avoidance, the emergency facility and the emergency capability five aspects.And the radius and the spatial equispaced of danger avoidance and accommodation service, the green exit passageway's width affect the functional evaluation of the urban green space system in disaster prevention and danger avoidance most. (2) Through the investigation on Changsha green space system present situation, we conclude that the linear green space construction is bad, the existing green space's organic network system is hard to form; The park green space distributing is uneven, the service radius is oversized.(3) Using the AHP analytic hierarchy process, we obtains Changsha green space system with disaster prevention and danger avoidance function appraisal result is "general". And,①the overall environment of disaster prevention and danger avoidance in Changsha is "good":The natural environment is quite superior; The artificial environment is quite suitable.②the spatial arrangement of disaster prevention and danger avoidance in Changsha is "good":The function is relative perfect, the independence is strong; Transportation system understanding is quite good.③the green space layout of disaster prevention and danger avoidance is "general":the green space's total quantity is reasonable, but the green space with disaster prevention and danger avoidance is few;The total quantity of danger avoidance and accommodation meet the requirements basically, but distributes unevenly;The passageway of urgent rescuing is excessively narrow; The isolation cushion greenbelt has not formed the ideal defense circle.④The emergency facility is "bad":the matching facilities construction with disaster prevention and danger avoidance in the whole city is very few.⑤The emergency capability is "bad":the propaganda and the drilling of disaster prevention and danger avoidance does not arrive.(4) While analyzing Changsha green space system with disaster prevention and danger avoidance function appraisal result, we proposed improving the green space system in Changsha with disaster prevention and danger avoidance plan mentality from perfecting related law, consummated the disaster prevention and danger avoidance system, to strengthen the emergency facility and to sharpen the emergency capability four aspects to embark.At last, because of the appraisal system's complexity, the partial targets will omit or redundant unavoidably.Same as collecting the data is very limited, the majority will be unable from the quantification angle to carry on the appraisal, its accuracy will wait for enhancing. Hope that in the following work will use more quantitative targets from crosswise and on longitudinal to conducts the contrast research and enhance this system's scientificalness.