关键词: 生态效率, 产业产出, 投入产出分析, 生产要素

Abstract:

One of the goals of China's strategy for a smart, sustainable and inclusive growth is the reduction of CO₂ emissions in the meantime keeping economic growth, which requires an increase of eco-efficiency. This paper defines improving eco-efficiency as achieving more goods and service outputs with less resource inputs as well as less waste and emissions. With special focus on low-carbon economy and decoupling carbon emission from economic development, here only GHG is taken into consideration in measuring China's eco-efficiency.
Starting from Leontief input-output analysis, this paper uses a system optimization model with the constraints for primary inputs to measure the eco-efficiency of an economy, and examine the contributions of individual production factors, desirable outputs and pollutions to eco-efficiency change over time. Employing a multiple objective optimization model an eco-efficiency frontier of the economy is generated, the solutions of which define the virtual eco-efficient decision making units. Then the eco-efficiency of the economy can be obtained as the difference between the potential of an economy and its actual performance. This model considers inputs, desirable outputs and undesirable output (GHG emission only) simultaneously, and takes into account both economical and ecological aspects. Having derived the score of eco-efficiency, a Luenberger productivity indicator is proposed to estimate the eco-productivity change over time; this is then decomposed in a way that enables one to examine the contributions of individual production factors, individual pollutants and individual commodities to eco-productivity change. The results allow an inference as to whether economic growth, primary input-saving or emission abatement are the underlying driving forces for eco-efficiency change.
Based on China's input-output tables, this paper calculates and compares our country's ecoefficiency performance between 1997 and 2010. A clear eco-efficiency regress of 50% was observed in China during this period, mainly due to the changes in both factor uses and sectoral outputs. Out of the 0.0096 total absolute decrease of eco-efficiency score, primary factor contributes 0.0078, and sectoral output leads to 0.0066, while GHG reduction activities bring about 0.0048 increase. Therefore, it could be concluded that in the past over 10 years, industrial development as well as factor use did not achieve the efficiency frontier, while emission abatement made such a great progress that it improves the efficiency of the economy. Among labor, capital and land, skilled labor is the only scare factor of production which might affect eco-efficiency. During 1997-2010, decreasing utilization of scarce high-skill labor enlarged the distance between the actual production and the efficiency frontier, and thus reduced eco-efficiency. Twelve out of the 18 industries made positive contribution to the efficiency change, while the remaining six including food processing, textile, non-metallic products, transport and services acted as obstacles. The results above would help identify the key sectors and inputs towards the objective of low-carbon growth.

Key words: input-output analysis, factors of production, eco-efficiency, sectoral output