碳交易背景下中国华北地区碳代谢格局变化

碳排放权交易市场作为推进美丽中国建设、实现降碳减污绿色发展的重要手段，成为当前研究的热点问题.为探究碳交易背景下华北地区试点区域及非试点区域碳代谢过程，以城市碳代谢理论为依据，采取投入产出分析和生态网络分析相结合的研究方法.结果表明，北京和天津作为早期交易试点区域，区域从2012年后呈现直接碳排放量稳步下降、隐含碳排放量缓慢增加趋势.试点产业部门直接排放量与隐含排放量变化趋势一致，其中煤炭开采和洗选业、石油和天然气开采业和非金属矿物制品业减排效应明显，而排放量较高的电力、热力的生产和供应业表现为增加趋势.部门隐含碳排放强度与隐含碳排放量变化趋势相似证实部门隐含增加值在交易过程中并未增加.高碳排放部门的隐含碳排放量主要由长度小于6的代谢路径所贡献，因此应重点关注部门间较短路径传递的商品或服务的“清洁化”.在交易政策实施以前，区域产业部门间跨区域贸易较少，表现为低碳排放产品交换；2012年以后，随着京津冀城市群协同发展以及华北地区不断构筑的区域经济发展新格局，促使区域间跨区域和跨部门贸易增加.以碳排放权交易制度为背景，构建识别系统内关键参与者及关键路径的方法体系，可为区域性政策实施及可持续发展提供科学的发展建议.

Dynamic Analysis on Carbon Metabolism of the Northern Region of China Under the Background of Carbon Emission Trading Policy

The launch of the national carbon emissions trading market in China is a policy to carry out the Beautiful China initiative and to establish a low-carbon economic development system that promotes carbon emission and waste reduction. In order to detect the carbon metabolic processes of the pilot and nonpilot municipalities or provinces in the northern region of China， the theory of urban carbon metabolism and the methods of input-output analysis and ecological network analysis were introduced and used. The results showed that the direct carbon emissions of Beijing and Tianjin had decreased， but their embodied carbon emissions had increased since 2012. The direct and embodied carbon emissions of the pilot sectors in Beijing and Tianjin had the same trend； specifically， the emissions of the sectors of mining and washing of coal， extraction of petroleum and natural gas， and manufacture of non-metallic mineral products decreased significantly， but the sectors of production and supply of electric power and steam with high carbon emission increased. The same trend of the embodied carbon emission intensities of sectors with that of their embodied carbon emissions verified that the embodied added values were not growing with the promotion of the carbon emission trading market. Subsequently， the embodied carbon emission of the pilot sectors in all the municipalities and provinces of the northern region were all contributed mainly by the emissions embodied by a path length less than 6； therefore， it showed that more attention should be paid to the trade among sectors with a path length less than 6 and reducing their carbon emissions. Furthermore， from 2007 to 2012， products or service trading among sectors mostly concentrated on sectors within one municipality or province， and these products or services had the characteristics of low carbon emission. Since 2012， the integration development of the Beijing-Tianjin-Hebei urban agglomeration and the new regional economic patterns established in the northern region both promoted the trading across provinces and across sectors. This research is based on the background of the carbon emission trading policy and aims to build a methodology to identify the key actors and paths in a metabolic system. This could provide a scientific basis for regional policy implementation and regional long-term sustainable development.