城市可持续规划中的生态敏感区避让分析——以丽江市为例

Abstract

Urbanization is profoundly changing the sustainability of cities.On the one hand,the economy and society are developing rapidly,accompanied by an intense growth in the urban population that has exceeded growth in the rural population.On the other hand,urbanization is associated with a dramatic change in land use.The urban ecosystem and the surrounding natural ecosystem have been undergoing profound changes,some of which may undermine the foundations of the sustainable development of cities.The scientific and rational planning of urban spatial patterns is crucial in fostering the sustainability of cities.In planning procedures,emphasis should be placed on the maintenance of indigenous special ecoenvironmental elements,ecosystem services and the human settlement of indigenous persons,which are important to thesustainability of cities.As a famous tourist city and a world heritage site,Lijiang City has experienced a dramatic urban expansion during the last few decades.Meanwhile,it is facing many related environmental problems,including the degradation of riverine ecosystem services,noise pollution in the Old Town of Lijiang City,and forest fires at the wild-urban interface.All of these issues threaten the sustainability of Lijiang City.To maintain its sustainable development,this paper proposed an improved land planning methodology based on ecological sensitivity analysis.This would aim to prevent the city from future environmental problems,which would limit its development.By avoiding such environmental issues,an urban spatial pattern that aimed to ensure the sustainable development of the city could be developed.By analyzing the environmental problems of the city,the authors focused on three ecologically sensitive factors:namely,the water system,noise pollution and forest fires.Water is the soul of Lijiang City,and it is a distinctive ecological element.The condition of the water system is important to the integrity of ecosystem services and the normal operation of the city.With the development of tourism,the noise pollution in the Old Town of Lijiang City is becoming serious.It is closely allied to people's wellbeing and a harmonious society.Urban expansion increases the area of the wild-urban interface,which may increase the risk of forest fires.This is related to the security of the city.So,all three factors are essential to the sustainability of Lijiang City.By considering the potential damage each factor may cause,this paper assigned a corresponding importance to each of the factors.The authors then zoned the ecologically sensitive areas and analyzed how—and to what extent—to avoid these areas in land planning.The results indicated that the most important areas for ecological protection and sustainable development were the lakes and rivers around the Lijiang basin,and the areas with high population density around,or in,the Old Town of Lijiang City.Thus the authors concluded that these regions must be avoided in urban planning strategy.The area of these regions was 147.2 km2,which accounted for 11.1% of the study area.Meanwhile,48.3% of the study area was of low sensitivity and mainly located in the northeast of the study area,surrounding the Lijiang basin and Yulong Snow Mountain.In addition,other limited areas for urban planning land were also identified and principles of avoidance were proposed accordingly.