多尺度地理加权回归模型支持下的汾河流域生态系统服务关系演化机理研究

Evolution mechanism of ecosystem service relationship in the Fenhe River Basin based on multiscale geographically weighted regression

生态系统服务权衡协同关系是掌握区域生态演化机理的重要指标。大量研究以行政区作为整体,对区域内的生态系统服务权衡协同关系进行描述,但是有关区域内生态系统服务空间异质性及多种生态系统服务间影响差异性的研究尚缺乏。本文以汾河流域作为研究区,基于1986年、1995年、2005年、2015年4期影像解译得到的土地利用分类结果,以及统计和生态数据,利用多尺度地理加权回归模型(MGWR)对生态系统服务权衡协同关系进行分析,并通过与土地利用数据相结合,定量分析土地转移对生态系统服务权衡协同关系的影响,探究生态系统服务的演化机理。研究表明:多尺度地理加权回归模型能解决生态系统服务权衡协同关系存在的空间异质性,从而准确揭示多种生态系统服务之间的内在关系;利用多尺度地理加权回归模型获得最佳生态系统服务组合的方式能有效降低数据冗余,提高工作效率;土地利用类型的变化是生态系统服务权衡协同关系演化的主要驱动因素;流域内植被退化会使粮食生产和产水量之间的权衡关系下降,使生物多样性和产水量等其他生态服务之间的协同关系下降;1986年—2015年间流域内单项生态系统服务间以协同关系为主导,且水源涵养与产水量间的协同关系最显著,平均协同率为75.6%。研究结果可为汾河流域土地利用优化和生态系统服务改善提供参考。

The trade-offs and synergies of ecosystem services are important indicators for understanding regional ecological evolution mechanisms.Many studies have taken administrative regions as a whole to describe the trade-offs and synergies of ecosystem services.However,the researchs on the spatial heterogeneity of regional ecosystem services and the different impact of various ecosystem services remains lacking.In our study,the Fenhe River basin was taken as the study area.Based on the land use classification results obtained by interpreting remote sensing images of 1986,1995,2005,and 2015,statistical data,and ecological data,we used the multiscale geographically weighted regression(MGWR)to analyze the trade-off and synergy between ecosystem service’s indicators of the Fenhe River basin.The influence of land transfer on the trade-off synergy and the evolution mechanism of the Fenhe River Basin’s ecosystem services was quantitatively analyzed by combining MGWR with the land use.The results show that:(1)MGWR can detect the spatial heterogeneity in the trade-off synergy of ecosystem service,and thus accurately revealing the internal relationship between multiple ecosystem services.(2)Using MGWR to obtain the best combination of ecosystem services can effectively reduce data redundancy and improve work efficiency.(3)Land use conversion is a major driver of the evolution of ecosystem service’s trade-off synergy.(4)Vegetation degradation in the Fenhe River basin will reduce the trade-off between grain production and water yield and decrease the synergy between other ecological services like the synergy of biological diversity and water yield.(5)From 1986 to 2015,the synergistic relationship between individual ecosystem services in the Fenhe River basin was dominant.The synergistic relationship between water conservation and water yield was the most significant,with an average synergistic rate of 75.6%.The point of this study is the use of MGWR in solving the spatial heterogeneity of regional ecosystem service.We found that MGWR can not only reduce the analysis error caused by spatial heterogeneity but also obtain the optimal ecosystem service combination efficiently,which means it can reduce the data redundancy of ecosystem service analysis.The results can provide a reference for land use optimization and ecosystem service improvement in the Fenhe River basin.