基于MSPA和MCR模型的城市生态空间优化——以四川江油市为例

Urban Ecological Space Optimization Based on MSPA and MCR Model:A Case Study of Jiangyou City,Sichuan Province

为了构建四川省江油市生态空间网络,以期缓解城市发展过程中的景观破碎化和生态安全问题,基于形态生态学空间格局分析(MSPA)与景观连通度指数识别生态源地,采取最小累积阻力值模型(MCR)和重力模型构建生态网络.结果表明,6个核心生态源地主要分布在北部龙门山-大巴山台缘褶皱带,县域生态极敏感和高敏感区分布在北部高海拔地区以及涪江流域,县域整体阻力面呈中部高、四周低的特征;6条重要廊道主要分布在东部雁门镇、北部丰顺乡,而西部和南部缺少核心生态源地.结论:江油市域内生态源地和生态廊道分布极不均衡,通过生态网络优化,补充了4个核心生态源地和14条规划生态廊道,优化后的闭合度指数ɑ、连接度指数β、连通率指数γ分别提升为2.4、4.5、0.96,改善了生境连通性和生态服务功能.

In the paper,the ecological pattern of Jiangyou City was constructed to resolve the problems of landscape fragmentation and ecological security.Based on the spatial pattern analysis of morphology ecology(MSPA)to identify the ecological source,and the landscape pattern index and the ecological sensitivity are analyzed by ArcGIS technology.The minimum cumulative resistance value model(MCR)was used to extract the potential ecological corridor of the ecological source of Jiangyou City,and the ecological network was constructed by combining the gravity model.The results show that the six core ecological sources extracted based on the MSPA are mainly distributed in the fold belt of the LongmenShan-Dabashan terrace in the north.The ecologically sensitive and highly sensitive areas are mainly distributed in the northern high-altitude areas and the Fujiang River Basin,but the ecological risks such as soil erosion and water pollution are more serious once they are destroyed.The overall resistance of Jiangyou City is characterized by high in the middle and low in the surrounding area,and the spatial distribution of ecological corridors is uneven.There are 8 important corridors identified by gravity model,mainly distributed in the woodland and grassland areas of Yanmen Town in the east and Fengshun Town in the north,while the core ecological source areas in the west and south are lacking,and the distribution of ecological sources and ecological networks is extremely uneven.Conclusion:Through the optimization of the existing ecological network,four core ecological sources and 14 planned ecological corridors were supplemented,and the optimizedɑ(closure index),β(connectivity index)andγ(connectivity index)were 2.4,4.5 and 0.96 respectively,which improve habitat connectivity and ecosystem service functions.