基于MSPA和MCR模型的贵阳市2008—2017年景观连通性评价与时空特征

Landscape connectivity evaluation and temporal-spatial characteristics of Guiyang City from 2008 to 2017 based on MSPA and MCR models

在快速城市化和生态文明建设的耦合交互下,喀斯特山地城市景观破碎化程度加剧,对生态安全和景观可持续性产生影响。以典型黔中喀斯特山地城市贵阳市为对象,基于形态学空间格局分析(MSPA)方法识别生态源地,运用最小累积阻力模型,评价贵阳市2008、2013和2017年景观连通性,分析10年间贵阳市景观连通性以及生态廊道的时空变化特征。结果表明:2008—2017年,贵阳市景观类型变化特征以林地、建设用地和未利用地增加,耕地面积显著减少为主。研究时段内,贵阳市景观格局的核心区面积持续增长,景观连通性小幅上升,但孤岛面积增加明显,景观破碎化程度严重。贵阳市景观连通性整体较好,中等级以上连通性区域占研究区总面积的74%以上;10年间,贵阳市景观连通性水平表现出中心城区先变弱后增强,四周逐渐增强的趋势。贵阳市景观生态廊道长度和数量均先减后增。研究结果可为进一步优化喀斯特山地城市景观空间格局、构建生态安全网络格局提供参考。

Due to the coupling interaction of rapid urbanization and ecological civilization construction,the ecology and environment of karst cities are becoming more and more fragile and vulnerable,with consequences on ecological security and landscape sustainability.Taking Guiyang,a typical city with karst landscape in Guizhou Province,as an example,we applied Morphological Spatial Pattern Analysis(MSPA)method to identify ecological sources,used the minimum cumulative resistance model to evaluate the landscape connectivity of Guiyang in 2008,2013,and 2017,and analyzed the temporal-spatial change features of landscape connectivity.The results showed that from 2008 to 2017,the landscape types of Guiyang were characterized by enhancement of area of forests,construction lands and unused lands,but reduction in the area of cultivated lands.Within the study period,the core area of Guiyang landscape pattern continued to increase,the landscape connectivity increased slightly,the isolated island area increased significantly,and the degree of landscape fragmentation was serious.The overall connectivity of Guiyang landscape was good,with more than 74%of the study area being middle or high connectivity.Within the 10 years from 2008 to 2017,the level of landscape connectivity in Guiyang showed a trend of weakening first and then strengthening in the central city,and gradually strengthening in the surrounding area.The length and the number of landscape ecological corridors in Guiyang first decreased but then increased.Our results can provide reference to further optimizing the spatial pattern of karst mountain cities and constructing ecological security network.