泛长三角地区碳生态效率的空间格局及影响因素

碳生态效率反映碳排放产出的经济社会价值高低，是衡量可持续发展水平的重要指标。以泛长三角各市为对象，以揭示碳排放的经济社会效益为目标，构建经济产出效率和人口承载效率评估指标，研究碳生态效率的空间格局和影响因素。结果表明：经济产出效率和人口承载效率呈现不同的变化趋势和空间格局，2000-2014年，经济产出效率增长97%，人口承载效率下降68%，前者空间集聚度高于后者；核心区及部分沿江城市的经济产出效率较高、增长较快，人口承载效率较低、下降较慢，碳生态效率高于其他城市；经济产出和人口承载效率的影响因素类似、作用强度和方向不同，前者主要受产业结构促进，后者的影响因素包括但不限于产业结构，但产业结构优化抑制了人口承载效率提升。研究认为，经济和社会视角的碳生态效率变化趋势及影响因素作用方向存在差异，为通过政策调控实现经济和社会效益同步提升增加了难度，在推动经济增长的同时，进一步加快人口集聚、优化产业结构和能源结构、提高能源利用效率等是政策制定的优选方向。

Investigation of spatial pattern and influencing factors of carbon ecological efficiency in Pan-Yangtze River Delta

Carbon ecological efficiency reflects the relationship between carbon emission and socio-economic outputs and is an important characterization for regional sustainable development. We considered the Pan-Yangtze River Delta (PYRD)-one of the most economically developed and fast-changing regions in China-as a case area, and analyzed the spatial pattern of carbon ecological efficiency at city levels based on two indicators, economic output and population carrying efficiency, which indicated the economic and social outputs of carbon emission respectively. Spatial correlation and multiple regression analyses were adopted to analyze the influencing factors of carbon ecological efficiency. The main results and conclusions were as follows:the economic output and population carrying efficiencies, which showed different changing trends, increased by 97% and decreased by 68% from 2000 to 2014, respectively. The economic output efficiency, which increased from 0.23 to 0.34, exhibited a higher spatial agglomeration degree than that of the population carrying efficiency, which was lower and remained basically stable in 2000 and 2014. Cities at the peripheral region had higher economic output efficiency than those at the core region did in 2000, but the situation was reversed in 2014. The population carrying efficiency of cities at the peripheral region were always lower than that of cities at the core region. Some cities at the core region or along the Yangtze river with higher developmental levels than others, such as Shanghai and Nanjing, showed higher economic output efficiency and their decrease in population carrying efficiency was slower than that of most cities in PYRD, which indicated that their comprehensive carbon ecological efficiency were higher than other cities. The results of the influencing factors analysis indicated that the economic output and population carrying efficiencies were affected by similar factors, but their influence on the two indicators differed in intensities and directions. The major influencing factors of the economic output efficiency were specific to the economic structure, especially the proportion of service industry accounting for the gross domestic product (GDP). However, the influencing factors of the population carrying efficiency were more complicated, and included GDP per capita, urbanization rate, and the proportion of R&D input accounting for the GDP. This research revealed that the trends of carbon ecological efficiency could vary considerably with different measuring indicators, and PYRD was a case with increasing economic output efficiency and decreasing population carrying efficiency. Moreover, the major influencing factors of the various measuring indicators also differed and, therefore, it was difficult to promote the economic and social benefits with similar regulatory measures. Some of the more developed cities exhibited higher economic output efficiency and slower decreasing population carrying efficiency than the less developed cities did, and their measurement could be used to promote both economic and social benefits simultaneously. We concluded that the main orientation of policymaking was to promote population agglomeration, optimize the industrial and energy consumption structure, and increase energy utilization efficiency.