碳排放约束下中国西部地区环境效率评价

Environmental efficiency evaluation under carbon emission constraint in Western China

利用基于非期望产出的SBM模型测度分析了2000—2012年西部大开发以来中国西部地区在碳排放约束条件下的静态环境效率,同时运用Malmquist指数分析了环境效率的动态变化趋势,最后利用Tobit回归模型进行回归分析,分析了环境效率的相关影响因素,并提出了促进西部地区环境提升的可行建议.结果表明：碳排放约束下的西部地区环境效率明显低于无碳排放约束下的环境效率,两者之间的差距呈先增大后缩小的倒＂U＂型关系;在碳排放约束下,广西、内蒙古一直处于相对有效状态,而贵州、甘肃、青海、宁夏、新疆一直处于非有效状态,且效率值普遍偏低,其中宁夏的效率值只有0.281~0.386,一直处于最低水平;西部地区的环境效率虽然普遍处于非有效状态,但环境质量呈逐年好转趋势,年平均提高6.6%;西部地区环境效率损失的最主要原因是过多的CO2排放量和能源消费量,能源强度对环境效率具有最大程度的负向影响;进出口贸易总额的增加显著降低了环境效率,而外商直接投资的增加则对环境效率的提高有积极作用.

This research used the SBM model based on undesirable outputs to measure the static en- vironmental efficiency of Western China under carbon emission constraint from 2000 to 2012. The researchers also utilized the Malmquist index to further analyze the change tendency of environmen- tal efficiency. Additionally, Tobit regression analysis was used to study the factors relevant to envi- ronmental efficiency. Practical solutions to improve environmental quality in Western China were put forward. The study showed that in Western China, environmental efficiency with carbon emission constraint was significantly lower than that without carbon emission constraint, and the difference could be described as an inverse U-shaped xi and Inner Mongolia, the two provinces curve which increased at first and then decreased. Guang- met the effective environmental efficiency levels all the time under carbon emission constraint. However, the five provinces of Guizhou, Gansu, Qinghai Ningxia and Xinjiang did not. Furthermore, Ningxia had the lowest level of environmental efficien- cy, with a score between 0.281-0.386. Although the environmental efficiency of most provinces was currently at an ineffective level, the environmental efficiency quality was gradually improving at an average speed of 6.6%. Excessive CO2 emission and a large amount of energy consumption were the primary factors causing environmental inefficiency in Western China, and energy intensity had the most negative impact on the environmental efficiency. The increase of import and export trade re- duced the environmental efficiency significantly in Western China, while the increase of foreign di- rect investment had a positive effect on its environmental efficiency.