足迹家族研究综述

Footprint family: current practices,challenges and future prospects

综合测度人类社会的可持续发展状态是生态经济学者追求的重要目标。足迹家族由生态足迹、碳足迹和水足迹等一系列足迹类指标整合而成,旨在为决策者系统评估与权衡人类活动的环境影响提供理论和技术支持。从理论探索、整合实践和分类比较等三方面对足迹家族的研究现状进行了综述;在此基础上围绕极具争议的足迹定义、计算方法和加权方式等问题,深入分析了阻碍当前研究进一步推进的关键性因素;指出未来应从建立足迹类型学、完善跨区域投入产出模型、细化产品和机构环境足迹标准等方面入手,推动实现足迹家族的量化整合;并首次提出了足迹家族与行星边界耦合的构想,以期为监测和预警人类活动的生态阈值、促进环境影响评价向可持续性评价转变提供科学依据。

It is increasingly widely accepted that anthropogenic impacts on the earth＇s systems should stay within critical thresholds for humanity to preserve the planet as a pleasant living place and as a source of welfare. It is therefore a high priority for ecological economists to identify and quantify the state of sustainable development of the human society. Efforts have been made to build up a footprint family in which a suite of footprint-style indicators, such as the ecological, carbon, and water footprints, are combined to measure the environmental impacts associated with human activities in multiple dimensions. The footprint family concept stems from the firm belief that environmental issues are getting increasingly complex, and that wise policies in most cases cannot be formulated without some form of trade-offs among an ever-expanding number of stressors. This highlights the importance of identifying ways to quantitatively integrate different footprints and to minimize the total footprint from a system perspective, rather than emphasizing ＂net zero＂ solutions to individual footprints. As a fast-growing interdisciplinary topic, a number of footprint family studies have received great attention over recent years since its first appearance in the literature. By labeling current studies with theoretical exploration, integrated practice, and comparison and classification, a comprehensive review of the footprint family research is provided. Challenges remain in developing a truly integrated footprint family, especially in defining the footprint concept in a generally accepted way. The scarcity of calculation methods that are valid for various footprints on multiple scales ranging from a product, an organization, a nation, and even globally, and the uncertainty of dealing with weighting both within and between footprints, provide obstacles as well. To remove all these obstacles, the remainder of this paper presents a research agenda for updating the footprint family framework in future work. We call for the investigation of footprint typology, the development of multiregional input-output models, the concretization of operational guidelines for product and organizational environmental footprints, and the combination of footprint family and planetary boundaries. We believe that many well-grounded footprint models have the potential to consolidate the scientific foundation of planetary boundaries by providing a robust and reliable assessment of current environmental impacts and, conversely, that the planetary boundary concept could allow footprints to benchmark against thresholds for environmental impacts that humanity is placing on the planet, as a clear recognition of sustainable limits to human interference is lacking in many of the existing footprint accounts. Thus, we come to the conviction that the joint use of a footprint family and planetary boundaries would contribute to the assessment of global sustainability from a broader point of view, in which current environmental impacts and forecasted threshold boundaries can be synchronously quantified and compared. In this manner, the footprint-boundary alignment makes it possible for policy makers to monitor the extent to which critical thresholds are being approached or exceeded, and to warn about critical transitions that may have profoundly undesirable consequences for environmental quality, ecosystem stability, and human health in large parts of the world.