基于AHP和FR模型的城市绿地适宜性评价

Suitability assessment of urban green space based on AHP and FR model

适宜性评价能够协调城市发展与生态环境保护之间的矛盾。以常州市为例,基于对航片的解译及实地调查提取研究区绿地信息,根据各种专题图建立空间属性数据库,利用ArcGIS9.3的Spatial Analyst工具,对适宜性影响因子(土地利用、植被指数、人口密度等)进行分析,运用层次分析法(AHP)和频率比(FR)模型,分析了常州市城市绿地的生态适宜性,并结合ROC曲线对两种方法进行检验和优选,针对分析结果提出常州市绿地系统规划建议。分析结果表明:权重变化对基于AHP法的适宜性评价结果影响不大,常州市城市绿地综合生态适宜性的空间分布规律大致为西部高,中部低。FR模型下高度适宜和较适宜区占研究区总面积的24.14%,以较大面积的绿地及苗圃地为主;不适宜区占研究区总面积的17.75%,以中心城区的建设用地为主。根据FR模型和3组AHP法计算出来的ROC曲线下的面积分别为:0.724、0.604、0.612和0.597。

Suitability analysis could coordinate the conflict between urban development and environmental protection. For suitability index mapping, green space locations were identified in the study area from interpretation of aerial photo- graphs and field surveys, and a spatial attribute information database was constructed from each special graph. The spa- tial analyst tool in ArcGISg. 3 was used to analysis the factors that influence green space suitability, such as land use, vegetation index, population density, distance from road and water. This study compares suitability index （SI） map which was created by using frequency ratio （FR） and analytical hierarchy process （AHP） approaches to analysis urban green space suitability in Changzhou. Correlation were examined among the models using relative operating characteristic （ROC） and gives the planning advance to green space system of Changzhou. The results showed that the change of weight have little impact to the result of AHP based suitability analysis. The spatial distribution patterns of ecological suitability of Changzhou green space were that western area performed higher suitability, while lower suitability was found in the middle area. The high suitability region were mainly large green space and nursery which accounts for 24. 14 % of the total area; while the low suitability region was mainly construction land which accounted for 17.75 % of the total area. The ROC analyses gave results of 0.724, 0. 604, 0.612 and 0. 597 for the FR, AHP SI maps.