Research On Ecology-Coupled Mechanism And Planning Strategy Of Urban Green Space Pattern In Xi’an

Through the gradual development of primitive society’s “reverencing nature”,agriculture period’s “transforming nature”,industrial age’s “conquering nature”,the current human civilization has begun to usher in a new eco-oriented stage,which advocates “respecting nature”.However,the ideal ecological transformation won’t be accomplished in one action,numerous cities in our country are still extending the unilateral development mode and unordered expansion ways,thereby results in mass of the serious eco-environmental problems together with the dilemma of Planning and construction in recent years,such as frequent fog and haze in winter,continuous high-temperature in summer,long-term high energy costs and pollutant release,as well as the unlimited expansion of urban land,lowlevel construction of urban space and environment,etc.Under the austere situation,as the“prior space” of human settlement’s Optimization and eco-efficiency’s promotion in urban area,the green space will be no longer confined to only possess the isolated and enclosed “shallow function”,such as landscape aesthetics,leisure tourism and cultural symbolization,on the contrary,it ought to become a more integrative and open spatial system to achieve the “deep coupling” with the urban ecological background and security.As a typical case of big city with plain topography in North China,Xi’an has undergone the evolution of many historical periods and several rounds of modern urban planning,from feudal age end,democratic revolution period,Anti-Japanese War period,liberation period,to new China’s reinstating the production,Cultural Revolution’s upheaval,reform and opening-up,and turning of the century,till the current New Period.Now it has appeared to be a complex built-up status with the superposition of old-new districts and the miscellaneous combination of diverse textures.At the same time,Xi’an’s green space has also kept a foothold on the “regional geography background,traditional landscape context,urban-rural development gap,upper-planning structure”,and then gradually come into the current form of site layout and characteristics of landscape style.However,the present green space pattern doesn’t achieve the “systematic coupling” with the inherent urban ecological background and ecological elements in a maximum extent,as well as the ideal ecological benefits’ releasing.Therefore,under the realistic predicament and demands that various types of eco-environmental problems emerge in an endless stream and overall ecological habitat quality needs to be improved urgently,the research on the “eco-coupled” space construction mechanism and the strategy of planning and design aiming at urban green space pattern,has become really necessary and pressing.Firstly,takes “construction of national ecological civilization and ecological garden city,transformation of urban-rural green space system and territory landscape ecological planning” as the macro context,keep to the point around the key concepts of “green space pattern,ecological coupling” and the relevant theories of “urban morphology,eco-city,ecological and environmental assessment,green space system,landscape ecology,urban climate,urban soil and water” and so on,taking which as the summarization of researches at home and abroad.Thus reach the conclusion that the ecological transformation and upgrading of urban space,not only need to take “limiting the undisciplined growth of urban size and land area” and “protecting the regional ecological and agricultural space”as fundamental methods,but also need to proceed from “making the evolution venation of urban spatial environment clear,identifying the natural background,ecological base,green space’s foundation of the city,historical layout and humanistic pattern”,then dominated by ecological elements,features and rules,and lead by urban afforestation and landscape creation,ultimately take green space as the breakthrough and vanguard leaders,guiding the urban ecological planning.Thereby achieve the goal of urban planning and construction’s “Ecological coupling”.Secondly,focus on the research object of Xi’an’s green space pattern,and to be specific to comb its urban-rural regional ecological background,including the ordinary and local ecological element composition,ecological background characteristics,and the evaluation and overlaying of each ecological security patterns in the administrative region level,including “comprehensive hydrology,engineering,water and soil conservation,biological and landscape diversity,cultivated land protection,wind environment,culture heritage preserving” and so on.Next,in the metropolitan area level,include evolutionary mode with the historical stages of development and analysis of current landscape pattern composition with a series of 15 character index.Moreover,after the above analysis by means of dynamic-steady’s combination,then through the method of cluster annlysis to screen the appropriate indexes,thus take the external evaluation about green space pattern’s eco-coupled benefits with the three-aspects’ index system about “6 quantitative indexes of planning and construction,6 qualitative indexes of landscape and environment,6 sensory indexes of humanity and recreation”.Then get the planning bottleneck and construction short board about green space’s coupling with the key ecological elements.Next,overlay the green space pattern with the ecological elements’ security patterns of comprehensive and each single kind,generalize the coupling mode and evaluate the coupling degree between them.For details,in the administrative city region level,mainly carry out the spatial and statistical analysis the situation of “hierarchical alignment” and“scope’s superposition” from each type of green space and natural protected area system with the comprehensive ecological security pattern.And in the metropolitan level,emphasize to evaluate the typical coupling modes and measurable coupling degree between the public green space and 4 ecological elements of “water,land,wind,culture”.Thus reveal Xi’an green space’s existing ecology-coupled mechanism and future direction of optimization and Improvement.Finally,put the preceding analysis results of green space’s eco-coupling and ideal prospect into planning strategy.For details,on the precondition of reasonable “planning scope,factors and steps”,establish the “rules,principles,guidelines” belong to different scales,and also separately propose: 1.green space’s eco-coupled planning “structure” in city administrative region level,2.overall eco-coupled planning “layout” with key elements’ eco-coupled planning “configuration”,including “surface water system and depth of groundwater level” for “water” coupling factor,“elevation,slope gradient,geologic hazard and engineering geology” for “landform” factor,“wind speed and direction” for “wind” factor,“officially protecet monuments and sites of each level” for“culture” factor and so on.3.Furthermore,based on the above overall distribution,and in the levels of “urban districts,key area and typical scenery spot”,continue to separately put forward the detail design demonstration programs and scene analysis about green landscape’s coupling with the correlative ecological background and elements.This research takes green space as subject,and ecological elements as object,through the evaluations of ecological security pattern,comprehensive ecological benefits and ecocoupled mechanism,reveal the current coupling degree between urban green space’s ecological planning-construction mode and the ecological space,process and connotation.Then summarize up the ecological background,which Xi’an urban green space located at,to 4 types basic ecological element(factors),including “water(water system connecting rivers and lakes),landform(topography and geology),wind(wind and thermal environment)and culture(cultural heritage)” for detail.And transform each respective “feature space” into the unitized “ecological security pattern(level),therefore obtain the green space pattern’s “single item-comprehensive” eco-coupled mechanism and degree.Proceed to the next step,in the aspect of planning strategy,separately put forward the eco-coupled configuration between green space pattern with “water system network,landscape context,ventilation corridor,heritage series”,especially focuses on the “wind” and “landform” factors to build the “urban air corridor” and “landscape greenway’s” planning system,as well as the conceptual design of representative area and scenic spot,therefore realize the special superposition,form fitting,and functional coupling between green space and ecological environment.In summary,according to regional ecological background,evolution,benefits,at the planning level,explore and analyze the green space’s current ecological-coupled mechanism and future ideal vision.At the design level,strengthen and highlight green space’s concept and effect of “eco+”.Therefore,being collectively directed against the weak point of green space pattern’s construction according to the specific single ecological element and overall ecological security pattern,provide the eco-coupled approaches of “ecological base building,element traction,human-earth harmony” for new type of urban ecological planning and green space system planning,and also find out the theoretical and practical path in the aspect of planning upgrading and strategy formulation at a certain extent.