Construction Of Ecological Network Of New Urban District Based On Niche Theory

Ecological sustainability is a long-term issue of urban development in China.The new urban area is the focus of future urban development and will be guided by green ecological health.With the increasing emphasis on ecology in the national land spatial planning and the recent public health emergencies,higher demands have been placed on the construction of ecological networks in new urban areas.How to build an ecological network of new urban areas under the new situation is the main purpose of this study.Based on the niche theory,this paper explores the construction method and optimization strategy of the ecological network,focusing on the following contents:First,study the niche theory and extract six principles,and get seven ecological network construction principles through theoretical deduction,as follows:(1)based on the principle of minimum threshold of ecological environment--baseline control of built-up area and ecological space;(2)Based on the "situation" theory of ecological niche--the "situation" theory of ecological space in new urban areas;(3)Diverse theory based on niche--multi-dimensional and diverse theory of ecological environment and species;(4)based on niche differentiation theory--ecological network main body differentiation theory;(5)overlap theory based on niche--overlap intervention theory of ecological network;(6)Compression theory based on niche--compression theory of ecological network;(7)Expansion theory based on niche--expansion theory of ecological network.Put forward six major construction indexes of ecological network: diversity,penetration,situation,diversity,overlap,and compression.Secondly,based on the ecological network construction principle based on niche theory,combined with expert scoring method and fuzzy Delphi method,six indicators of ecological network construction are extracted and determined: diversity,penetration,situation,diversity,overlap,Compression degree,formed a set of multi-dimensional index system including qualitative and quantitative combination of "ecological resources analysis-ecological network construction-optimization adjustment strategy".The specific measurement content and method of each indicator are summarized,and the expert group decision method is adopted to determine a reasonable three-level classification of each indicator.Then,based on the measurement and grading results of the six major indicators,combined with the development and positioning of the new urban area,a comprehensive evaluation of the qualitative and quantitative combination of the rating values of various indicators is made,and suggestions for sub-strategies are proposed.Finally,we got seven suggestions for the overall optimization strategy of the ecological network,as follows:(1)Ecological network core protection strateg;(2)Cooperative connection strategy of ecological network system;(3)Control the expansion strategy of the new area;(4)Differential positioning and hierarchical protection strategy of ecological network;(5)Ecological overlap restoration strategy;(6)Land use optimization strategy;(7)Ecological expansion strategy improves rating value.Finally,taking the Nansha New District of Guangzhou as an example to carry out practical research.A hierarchical analysis method was used to study the whole Nansha New District and "Six Towns and Three Streets" respectively,and to measure the indicators of ecological network construction.Combining the ecological network construction results of the multi-dimensional indicators and the analysis of the location development of the district,the ecological network optimization strategy is proposed,and finally the overall ecological network layout plan of the Nansha New District and the "six towns and three streets" is obtained.This research breaks through the perspective of traditional ecological network construction,improves the theoretical system of ecological network construction in new urban areas under the new situation,and expands the application field of niche theory.A set of qualitative and quantitative multi-dimensional ecological network construction index system is explored,which can quickly build an ecological network in a new urban area and conduct evaluation and optimization.This method can provide a reference for the practice of ecological spatial planning in new urban areas.