城市碳源碳汇的时空格局变化研究——以宁波市为例

Research on the spatiotemporal pattern changes of urban carbon sources and sinks:a case study of Ningbo

城市尺度的碳源碳汇核算及动态监测对实现碳中和发展路径至关重要.基于2005—2020年宁波市土地利用数据和相关统计数据,结合联合国政府间气候变化专门委员会(IPCC)碳排放核算法与InVEST模型的碳储量估算模块,分析宁波市碳源碳汇的时空格局变化特征,并提出了相应的碳平衡措施.研究结果表明:(1)2005年以来宁波城市碳排放总量快速增加,在2013年达到峰值(7.70×10^(9) t),总体维持在6.75×10^(9) t左右;工业部门是最大碳排放源,占据了碳排放总量的80%以上.(2)2005—2020年宁波市碳储量先降后增,到2010年缩减了0.10×10^(9)t,至2020年又增加了0.23×10^(9)t,累计增汇1.31×107t;用地类型中,林地增汇效果最显著,耕地较差.(3)在空间净碳排放强度方面,宁波市核心区域的空间净碳排放强度增长更显著.建议宁波市通过优化产业与能源结构、调整城市建设布局、加强生态修复等措施来减源增汇,通过建立区域间的碳汇补偿机制,营造低碳协调的发展环境.

Accounting and dynamic monitoring of carbon sources and sinks in cities are indispensable for realizing carbon-neutral development paths.Based on the time series of LUCC data and statistical data of various sectors in Ningbo from 2005 to 2020,this paper uses the IPCC carbon accounting method and the InVEST model to dynamically analyze the characteristics of changes in the spatial and temporal patterns of urban carbon sources and sinks in Ningbo since 2005,in an attempt to reveal its regional differences and carbon surplus.The results show that:(1)Since 2005,Ningbo’s total carbon emissions have increased rapidly,which reached 7.70×10^(9) t in 2013,and then declined slightly,remained at around 6.75×10^(9) t overall;among them,the industrial sector is the largest source of carbon emissions,accounting for more than 80%of the total carbon emissions.(2)Between 2005 and 2020,Ningbo’s carbon stock first declined and then increased,by 2010,it had decreased by 0.10×10^(9) t,and by 2020,it had increased by 0.23×10^(9) t,with a cumulative increase of 1.31×107 t;among land types,forest land has the most significant effect in increasing sinks,while arable land is less effective.(3)The spatial net carbon emission intensity has been growing faster in the core area of Ningbo than that in the peripheral areas.The Ningbo government should take measures to reduce carbon sources and increase carbon sinks,and promote the coordinated development of low carbon in all regions through the establishment of an inter-regional carbon sink compensation mechanism.