京津冀地区生态系统服务对城镇化的多空间尺度动态响应

Dynamic responses of ecosystem services to urbanization at multi-spatial scales in the Beijing-Tianjin-Hebei region

大规模的城镇化导致了城市不断扩张,给生态系统造成了巨大的压力。以京津冀地区为例,分析了2000—2020年间京津冀地区城镇化与生态系统服务的变化以及二者间的关系,并探讨了这种关系在栅格尺度、县域尺度、市域尺度上的尺度效应以及变化规律。利用InVEST模型对所选取的4项生态系统服务指标进行量化,并运用皮尔逊相关性分析和地理加权回归来检验其与4项城镇化指标间的关系。研究结果表明(1)随着京津冀地区城镇化的发展除碳储量下降了0.8%外其余生态系统服务均有所提升,其中生境质量增加0.8%、水分产量增加了68%、土壤保持能力增长了35.7%而粮食产量增长近三倍。(2)生态系统服务与城镇化间存在显著相关性(P<0.01),且相关性在县域尺度上最为显著。其中产水量与4项城镇化指标均呈现正相关,粮食产量、碳储量、土壤保持量及生境质量均与4项城镇化指标均呈现负相关。(3)地理加权回归结果表明,城镇化指标与生态系统服务仅在县域尺度上拟合度较好且具有明显的聚集趋势,其中城市用地占比与碳储量、粮食产量全域拟合度最高分别为0.42与0.63。在针对生态系统服务的管理上不同区域需要制定不同的政策,同时需要对尺度进行适当的动态调整。文章明确了城镇化对生态系统服务的影响,并强调了城镇化及生态系统服务关系间的尺度效应,为京津冀地区生态系统管理提供了参考。

With the rapid acceleration of China's urbanization process,cities across the country are in a rapid development.According to the data from the National Bureau of Statistics in 2021,China's population urbanization rate reached 64.72%.Large-scale urbanization has led to the expansion of cities,which has put enormous pressure on the ecosystems.The urbanization of Beijing-Tianjin-Hebei region(BTH)is the epitome and typical example of rapid urbanization development in China.In 2018,the urbanization rate of BTH has reached 65.8%.With the continuous advancement of urbanization,the natural ecosystem of the BTH has undergone a complex change,which posed a severe challenge to the sustainable development of the region.At the same time,the imbalance of regional development in the BTH is very serious.In this study,we analyzed the changes of urbanization and ecosystem services and the relationship between them in Beijing-Tianjin-Hebei region during 2000-2020.We also explored the scale effects and change patterns of this relationship at the grid scale,county scale,and municipal scale.The four urbanization indicators are nighttime light,urban land proportion,population density and GDP density,while the five ecosystem services indicators are water yield,food provisioning,soil conservation,carbon storage and habitat quality.In this study,the InVEST model was used to quantify the selected ecosystem services indicators,and the results of the four urbanization indicators were obtained by combining statistical data.Based on this,Pearson correlation analysis and geographically weighted regression were applied to test the relationship between them.The results showed that(1)the ecosystem services increased with the urbanization in the BTH,except for carbon storage,which decreased by 0.8%,with habitat quality increased by 0.8%,water yield increased by 68%,soil conservation increased by 35.7%,and food provisioning increased by nearly three times.(2)There was a significant correlation between ecosystem services and urbanization(P<0.01),and the correlation was the most significant at the county scale.Water yield was positively correlated with the four urbanization indicators,while food provisioning,carbon storage,soil conservation and habitat quality were all negatively correlated with the 4 urbanization indicators.There was also a significant correlation between ecosystem services.Carbon storage,soil conservation and habitat quality showed a trade-off on the three scales.At the same time,this correlation would increase with time.(3)The results of geographically weighted regression showed that the fitting degree of urbanization indicators and ecosystem services was high only on the county scale,and had a clearly spatial agglomeration characteristic.Among them,the fitting degree of urban land proportion,carbon storage and food provisioning was the highest,which were 0.42 and 0.63,respectively.It suggests that using the county scale as the study scale is to some extent a more accurate response to the impact of urbanization on ecosystem services.However,some ecosystem services were more correlated with urbanization indicators at the grid and municipal scales,so different policies needed to be developed for the management of ecosystem services in different regions,and the scales could be adjusted dynamically as appropriate.The article clarified the impact of urbanization on ecosystem services,and focused on the scale effects between urbanization and ecosystem services relationships,providing a reference for ecosystem management in the Beijing-Tianjin-Hebei region.