Research On The Optimization Of County Eco-Spatial Pattern In The Beijing-Tianjin-Hebei Region Targeted At Increasing Carbon Sinks

The establishment of the goal of "Emission Peak and Carbon Neutrality" places new requirements on the formulation of national territory development plan in the new era.The ecological space performs a significant role in achieving low-carbon function as a cardinal part of the national land.As a pioneer across China in the practice of green and low-carbon development,counties have demonstrated their massive potential of increasing carbon sinks.Currently,however,there are still few studies focusing on the relationship between ecological space and carbon sinks,which hinders the determination of related research to improve the capacity of regional carbon sinks based on spatial planning.Meanwhile,carbon sink elements have yet to be involved in the ecological space identification system,which presents a challenge in identifying the critical ecological regions and corresponding strategic pathway to increasing carbon sinks.Under this context,it is imperative to determine how to combine carbon sinks with ecological spatial plan for the optimization of ecological spatial pattern for the county given the goal of increasing carbon sinks.For all of the above-mentioned reasons,a county-level classification system was constructed according to ecological space identification given the aim of increasing carbon sinks,which requires the combination with feature,mechanism,recognition,classification and optimization.Firstly,an estimate was made of carbon sinks in counties,with its spatial-temporal characteristics analyzed.Secondly,geographic detectors were applied to identify the driving mechanism that can have impact on the spatial differentiation of county carbon sinks.Thirdly,the driving factors were screened and optimized as the final indicators.Besides,weighted overlay method was adopted to obtain the result of ecological space identification given the objective of increasing carbon sinks.Fourthly,the k-means method was applied to perform county classification.Based on the aforementioned results,the corresponding ecological spatial pattern optimization strategy was proposed.Taking Beijing-Tianjin-Hebei counties as research objects,this research estimated the total amount of carbon sinks for 200 counties across the Beijing-Tianjin-Hebei region from 1990 to 2020,which revealed their spatial-temporal patterns,demonstrated the driving mechanism behind the spatial differentiation of carbon sinks,as well as identified the bottom-line,auxiliary,and core ecological spaces across the BeijingTianjin-Hebei region given the aim of increasing carbon sinks.Moreover,the counties were classified into three characteristic categories to propose the solutions to optimizing the ecological spatial pattern.The research came to the following conclusions.Firstly,the spatial differentiation of carbon sinks at the county level results from the combined effects of natural and artificial elements,while the interaction between them will reinforce the spatial differentiation of carbon sinks.Secondly,the strategies adopted for optimizing ecological spatial pattern on county levels given the objective of increasing carbon sinks must b based on the current state for meeting the requirements of the counties on lowcarbon development given different classification characteristics.With the BeijingTianjin-Hebei region as an example,the guidance district strategy was proposed for the purpose of increasing carbon sinks,the guidance strategy of county classification was suggested on the basis of coordinated development,and the eco-spatial plan implementation guarantee system strategy was also put forward.