城市建设用地生态适宜性评价的 潜力-限制性分析 ——以大连城市化区为例

城市建设用地生态适宜性评价是合理利用我国有限土地资源的一项基础性工作,本研究的特色是以大连城市化区为例在归纳GIS方法应用的基础上,将目前国内广泛采用的单纯权重叠加法推广到加权的潜力—限制性分析法。该方法的主要优点是把评价要素分为生态潜力和生态限制性两大类,通过取大原则和成对明智比较法分别确定权重,从而更加科学确定土地利用生态适宜性等级。结果表明,大连可做高强度开发的城市建设用地面积约为850.46 km²,约占总面积的6.28%;可在指导下进行适度开发利用的土地面积为1835.97 km²,占总市域面积的13.56%;而不宜作为建设用地的土地(不适宜和中低适宜区)面积为10851.92km²,约占总市域面积的80.16%,即城市建设用地的影响范围应该控制在区域的20%土地利用类型中,另外80%的土地不适宜进行城市建设的开发。根据上述结果,全区规划分为优化建设区、重点建设区、限制建设区和禁止建设区,并提出用地分区发展管制对策。

Ecological suitability assessment on land use based on potential-constrain approach: The case of urbanized areas in Dalian city, China

Ecological suitability assessment on land use is one of the fundamental works to use the limited land resources in China rationally.The conflict between urban land use and eco-environmental protection is very intense in the rapidly urbanized area,and it's important to do ecological suitability assessment on land use in such an area.Based on summing up the application of GIS technology,this study develops a domestic widely-used weighted factor-overlay method and extends it to a weighted potential-constrain approach which is originally from cost-benefit analysis.The main advantage of this approach is to divide the assessment factors into two groups,one contains ecological potential factors,and the other the ecological constrain factors,to choose the factors under the principle intensively of data obtainable,and to determine their weights by choosing exact means.The employment of this approach could help to determine the ecological suitability classes more scientifically and reasonably.In this study the potential-constrain approach is employed in Dalian city region,the analysis shows:(1) the area that could be intensively developed for urban construction purpose is 850.46 km2 in Dalian city region,being about 6.28% of the total study area;(2) the area that could be developed moderately for construction purpose is 1835.97 km2,or about 13.56% of the total area;and(3) the area that could not be used or being moderately and lightly suitable for construction is 10851.92 km2,or about 80.16% of the total area.Hence the land used for urban construction should be controlled under 20% of the region's total area,and the remaining 80% could not be used for urban development.Furthermore,based on the ecological suitability assessment,four planning zones of construction improvement zone,construction emphasized zone,construction restricted zone and construction forbidden zone could be worked out,in which the development strategies and implementations in each zone are suggested.The following aspects could be discussed in the application of the potential-constrain approach:(1) the resolution of satellitic image,which is the basic data,is one of the most important reasons affecting the precision of the result of assessment,according to different levels and different regional scopes,the right size of satellitic image should be chosen to keep balance between quality and quantity of the data dealt with;and(2) to the exactly assessment object,the factors chosen,the weight determined and the overlaying process should be all considered scientifically and reasonably.