摘要
在当前全球变暖、极端天气频发的背景下,提升城市气候适应性和实现碳中和已成为人类应对气候风险的必然选择,优化城市形态和碳汇能力能够实现对局地气候环境的调节,从而强化城市抵御不利气候条件的韧性。因此,应用局地气候区框架(Local Climate Zone,LCZ)对城市区域微气候特征进行精细分类以精确量化城市生态系统净初级生产力(Net Primary Productivity,NPP),以此更准确探究城市不同形态碳汇能力。将LCZ方案和CASA模型相结合,以北京市中心城区为对象,深度聚焦2022年NPP动态演变,运用混淆矩阵、异常检测等多元统计分析NPP与不同LCZ类型内在关联,并探讨了NPP的时空维度变化及其季节性周期规律。研究表明:(1)中心城区以紧密型建成区(G1)为主,占36.4%,开敞型建成区(G2)占32.51%,自然类(G3)主要分布在西北部,占31.1%。(2)NPP季节性变化显著,季度均值先增加后减少,峰谷差值为1608.77gC m^(-2)a^(-1)。(3)NPP与光照、温度、水分等自然因素以及绿地率等人为因素均存在相关关系。根据不同LCZ类型的NPP变化构建了四个城市类型分区(E1、E2、E3、E4),并提出了针对性碳汇优化策略。研究结果为制定精准的气候适应策略和促进城市可持续发展提供了关键依据,具有重要的理论和实践意义。
Against the backdrop of intensifying global warming and frequent extreme weather events,improving the cities'climate adaptability and optimizing carbon sink management have become important ways to achieve the goal of carbon neutrality.Urban ecosystems can effectively regulate the local climate environment and enhance the cities'resilience to climate change through carbon absorption and storage processes.However,different land use patterns and building forms within cities lead to significant differences in carbon sink capacity.Therefore,based on the Local Climate Zone(LCZ)framework and combined with the improved CASA(Carnegie-Ames-Stanford Approach)model,this study analyzes the spatiotemporal variation characteristics of net primary productivity(NPP)in the central urban area of Beijing in 2022,and explores its relationship with climate factors and human factors.The study first classified the local climate zones in the central urban area of Beijing,and constructed a high-precision NPP estimation model using remote sensing data and Arc GIS spatial analysis methods.Combined with meteorological data such as temperature,precipitation,and light,as well as urban characteristic parameters such as green space coverage,statistical methods such as confusion matrix analysis and anomaly detection were used to explore the NPP change trend and driving mechanism of different LCZ types.The results show that:(1)The local climate zone types in the central urban area of Beijing mainly included compact built-up areas(G1,accounting for 36.4%),open built-up areas(G2,accounting for 32.51%)and natural areas(G3,accounting for 31.1%).Among them,G3 was mainly distributed in the northwest of the city and had a strong carbon sink capacity.(2)The seasonal variation of NPP was significant,showing a trend of rapid increase in spring,peaking in summer,and decreasing in autumn and winter,with the maximum peak-to-valley difference having reached 1608.77gC m^(-2)a^(-1).(3)NPP was significantly correlated with natural factors such as light,temperature,and moisture,as well as human factors such as urban green space coverage.In particular,in summer,high temperatures and sufficient precipitation promoted vegetation growth,which enhanced carbon sink capacity,while low temperatures and vegetation defoliation in winter lead to a significant decrease in NPP.On this basis,the study further constructed four urban functional zones(E1,E2,E3,and E4),and proposed targeted carbon sink optimization strategies.The E1 area is mainly distributed in high-density built-up areas.It is recommended to improve carbon sequestration capacity through roof greening and vertical greening.The E2 area is located in a medium-density urban functional area.The carbon sequestration benefit can be enhanced by optimizing green space configuration and building ecological isolation zones.The E3 area is mainly a natural local climate zone.Ecosystem protection should be strengthened to avoid overdevelopment.The E4 area is a mixed area.Urban renewal and ecological restoration should be combined to improve the overall carbon sequestration capacity.This study provides a refined analysis method for urban carbon sink assessment by combining LCZ classification with the CASA model,which helps to improve the scientificity and accuracy of carbon sink management.The research results can provide a scientific basis for formulating urban climate adaptation strategies,optimizing green space configuration,and improving carbon neutrality capabilities,and have important theoretical value and practical significance for promoting urban sustainable development.
作者
孙佳慧
周凯
郑曦
SUN Jiahui;ZHOU Kai;ZHENG Xi∗(Beijing Forestry University,Beijing 100083,China)
出处
《生态学报》
北大核心
2025年第15期7257-7276,共20页
Acta Ecologica Sinica
基金
国家自然科学基金面上项目(32371643)。
