生态足迹方法的理论解析

论文系统地解析了生态足迹概念，在简要介绍生态足迹账户框架建立的假设条件，计算方法的基础上，系统总结了生态足迹最近的国际研究进展。同时，重点介绍了生态足迹计算中容易引起误解和疏忽的两个问题：化石能源用地的处理，均衡因子和产量因子的计算。在此基础上，从生态足迹计算过程中化石能源的处理和“利息”的处理两个角度评价了生态足迹方法的局限性。同时从贸易的处理缺乏可持续性基础，忽视国家和区域尺度上空间地理情况的差异，忽视人类社会对自然资产“利息”流的积累和储存，忽视自然资产存量的状况四个角度，分析了生态足迹在不同尺度上应用中存在的问题，最后通过将生态足迹分析还原到IPAT等式，并从热力学和生态经济学的角度解释了现有生态足迹分析政策建议少并且雷同、及其政策建议缺乏可操作性的实质价值的原因。

A Resolution to the Conception of Ecological Footprint

Ecological footprint is one of the most important advances in the field of quantitatively measure sustainable development in recently 20 years.Ecological footprint is also popular in China recently.With a view to applying it more efficiently,we interpret the conception of Ecological Footprint and its theoretic basic systemically,and discuss its limitation combining with some current critics and our understanding in this paper.After providing the conceptual background and identifying the research question underlying the ecological footprint accounts,the paper firstly presents the conception framework of ecological footprint and its assumptions,and classify its calculation procedure into two parts:(1)building the connection between human demand and land-use categories by the consumption-land use matrix.(2) Aggregating the impact components in global hectares and compares with its ecological capacity by using the equivalence factor and yield factor.In the second part,we introduce the land requirement for fossil energy,renewable energy,nuclear energy and embodied energy respectively.The CO_2 sequestration method and biomass substitution method that used to calculate the fossil energy's footprint have been explained with the higher level of detail.At the same time,we show how to calculate the two conversion factors-equivalence factors and yield factors by using concrete numeric example.In the third part,some important advances have been demonstrated around the compound method,now used for national footprint accounting.Simultaneously,we also introduced some related methods that supplemented and strengthened the ecological footprint.In the fourth part,we discuss on the methodological limitations of Ecological Footprint method from the views of conversion the fossil energy consumption into fossil land,and the supply and demand of natural interests.Such contents as trade sustainability,spacial and regional difference,the stock of social resource and natural capital have not been included in the current framework of ecological footprint,we point that it is not appropriate to copy the global scale results into national and region scale.At the same time,the reason that the policy suggestions from the ecological footprint results is so little and consistent,have been showed by discussing the relationship between ecological footprint and classical IPAT identity.Some evidences have been used to explain why these policy suggestions are just heuristic from the view of thermodynamics and ecological economics.At last,we finish with a brief conclusion.