远程关联视角下中国碳储量在建设用地流动中的变化及驱动因素分析

Changes and driving forces of carbon storage in China’s construction land flow from a teleconnection perspective

建设用地转变是造成人为碳储量变化的主要原因之一,贸易产品的交换以及资源的流通使得建设用地受到远程关联的影响发生流动,负载其中的碳储量也因此产生流动和变化,因此有必要分析碳储量在建设用地流动中的变化,探明碳储量变化的驱动因素,为未来区域“双碳”目标实现和绿色可持续发展提供科学依据.本文利用土地利用数据、碳密度数据和投入产出数据,结合生态系统服务和权衡的综合评估模型的碳计算模块、多区域投入产出模型和结构分解分析等方法,揭示了2012~2017年间远程关联视角下中国建设用地碳储量的流动变化格局及在流动变化中碳损失热点,并分析各省份建设用地碳储量远程关联变化的驱动因素.结果表明:(1) 2012和2017年中国区域间建设用地碳储量流动值分别为483.3和580.7 Tg C,研究期内区域流动更为频繁,区域间的远程关联性更强,高频率流动量不仅仅只在经济较为发达的东部沿海地区,而是逐渐覆盖全国,经济发展稍滞后的东北、西南地区的流动量产生大幅度提升.(2)研究期间,中国各省份建设用地碳储量的净流入增长区集中于经济发展较好的中东部地区,净流出增加区集中于欠发达的东北部和西北部地区,发达地区为了满足自身发展建设需求,不仅占用了欠发达地区的土地资源,更进一步转移了对资源侵占所造成的碳储量损失,造成了生态不平等.其中,内蒙古净流出量增加最多,是碳储量损失热点,浙江净流入增加最多,是导致碳损失的重要省份.(3)消费规模和建设用地碳储量负载强度是影响流出量和流入量变化的主要因素,其中江苏等经济基础较好的省份,结构分解中表现出更多的消费规模增加和更多的建设用地碳储量负载强度减少,通过增加单位建设用地产值满足新增的外部规模需求.为了保护碳储量,缓解区域间的生态不平等,政策制定中要注重优化建设用地的管理机制,激活生态用地服务价值,健全生态补偿机制.

There is notable spatial heterogeneity in both resource distribution and economic development levels across different regions of China.As interregional trade continues to evolve,the economies of these regions become increasingly intertwined,resulting in a realignment of resource supply and demand for commodities.This economic interconnection has fostered teleconnections between regions.Concurrently,population growth has altered demand for various products and necessitated land expansion,particularly for urban development,leading to significant expansion of construction land and consequent carbon storage depletion,resulting in substantial carbon release into the atmosphere.The teleconnection effect of trade has not only intensified local demand for construction land but has also introduced external influences,impacting carbon storage levels on the land.Preserving carbon storage in land requires an analysis of changes in carbon storage within the flow of construction land and an exploration of the drivers behind these changes,followed by the formulation of pertinent policy recommendations.Utilizing land use data,carbon density data,and input-output data,this study integrates the carbon calculation module from an integrated assessment model for ecosystem services and trade-offs with a multiregional input-output model and structural decomposition analysis.Through this approach,we aim to elucidate the evolving pattern of carbon storage flow within China′s construction land from 2012 to 2017,under the lens of remote correlation,identifying hotspots of carbon loss within these flux changes.Furthermore,we analyze the driving factors behind changes in carbon storage flux in construction land across each province.The results show that:(1)The interregional flows of carbon storage in construction land within China amounted to 483.3 Tg C in 2012 and increased to 580.7 Tg C by 2017.This upward trend signals a heightened frequency of regional flows and underscores the strengthening of interregional teleconnections over the study period.Notably,high-frequency flows are not confined solely to the economically developed eastern coastal regions but have progressively extended throughout the entire country.Moreover,there has been a substantial increase in flows observed in the northeast and southwest regions,regions historically trailing behind in terms of economic development.(2)During the study period,the expansion of net inflows of carbon storage on construction land in each province of China was predominantly concentrated in the central-eastern region,characterized by more robust economic development.Conversely,the augmented area of net outflows was predominantly focused in the less-developed northeastern and northwest regions.In pursuit of their own developmental and construction imperatives,the more developed regions not only appropriated the land resources of their less developed counterparts but also exacerbated the loss of carbon storage resulting from resource encroachment,thus perpetuating ecological inequality.Among these regions,Inner Mongolia emerged as the province witnessing the most substantial increase in net outflows,thus becoming a hotspot for carbon stock loss.Conversely,Zhejiang experienced the largest surge in net inflows,underscoring its pivotal role in facilitating carbon loss.(3)Consumption scale and carbon storage loading intensity of construction land are the main factors affecting the change of outflow and inflow.Provinces with a higher economic level,such as Jiangsu,show a higher increase in the scale of construction land consumption in the structural decomposition,a higher decrease in the intensity of carbon stock loading,and a higher increase in the output value per unit of construction land to meet the new external scale demand.To protect carbon storage and alleviate ecological inequality between regions,policy formulation should focus on optimizing the management mechanism of construction land,activating the value of ecological land services,and improving the ecological compensation mechanism.