陈先鹏 方 恺

摘 要：在资源约束趋紧、环境压力加剧的背景下，科学界定人类活动的生态红线，成为资源环境承载力研究者关注的重大课题。本文通过回顾承载力概念的发展与演变，指出承载力虽然是一个相对的、动态的概念，但在一定的社会经济条件下仍可量化。行星边界理论作为近年来国际承载力量化研究的标志性成果，为基于“地球系统观”理解资源环境承载力的科学内涵提供了崭新的视角。本文对行星边界理论的缘起、发展与应用进行了系统回顾，并在此基础上探讨了其面临的主要挑战与机遇。研究表明，行星边界是科学文献与专家知识相结合的产物，用于表征地球生物物理过程不确定性区间的起始端，然而这些生物物理过程具有不同的时空属性、临界行为和不确定性区间，且相互之间存在复杂的交互作用关系，因而关于地球生物圈是否存在临界阈值尚存争议。行星边界理论应用于区域尺度时基本遵循2种路径：(1)基于全球视角自上而下分配，如对应气候变化的碳边界具有较高的接受度；(2)基于本地视角自下而上整合，如土地和水边界体现了各系统过程的空间异质性。行星边界理论在地球系统过程的尺度属性、生物物理阈值的时序变化、与环境足迹的整合以及向社会经济维度的拓展等方面面临较大挑战。今后需进一步深化对地球环境系统反馈机制及其与人类社会交互胁迫等的研究，提升其在资源环境承载力量化领域的应用价值。

关键词：承载力；行星边界；生物物理过程；阈值；尺度

Advancements in Quantifying the Carrying Capacity of Resources and the Environment：On the Origin，Development and Challenges of the Planetary Boundaries Theory(www.daowen.com)

CHEN Xianpeng FANG Kai

Abstract：Given the increasing resource constraints and environmental pressure，it is crucial to quantify science-based carrying capacity，beyond which anthropogenic activities may lead to undesirable or disastrous consequences.On the basis of a review of the development of the concept of carrying capacity，this paper argues that carrying capacity can be quantified under certain socio-economic conditions，although it is a relative and dynamic concept.As a landmark of international quantitative research on carrying capacity in recent years，the planetary boundaries theory opened the way for a systemic understanding of the scientific underpinning of the carrying capacity of resources and the environment from the view of Earth system.For this reason，the origin，development and application of planetary boundaries are systematically reviewed，and the main challenges and opportunities for the theory are discussed.The research shows that planetary boundaries to characterize the initial boundaries of the uncertainty range of biophysical processes of the Earth are determined based on the combination of scientific literature and expert knowledge.However，these biophysical processes have different spatio-temporal properties，critical behaviors and uncertainties，and there are complex interactions among them.As a result，it is still controversial whether critical thresholds for the terrestrial biosphere are evidently existent.The downscaling of planetary boundaries to the regional and local scales can be achieved through：(1)top-down allocation from a global perspective，such as the high acceptance of the carbon boundaries for climate change；(2)bottom-up integration from a local perspective，such as land and water boundaries for relevant Earth-system processes that show explicitly spatial heterogeneity.The planetary boundaries theory is now facing the challenges of the scaling of the Earth-system processes，the variations of biophysical thresholds，the integration with environmental footprints，the extensions to the social and economic dimensions of sustainability，and so on.Therefore，further improvements need to focus on the feedback mechanism of the Earth environmental system and the interactions with human society，and extend its application to quantifying the carrying capacity of resources and the environment.

Key words：carrying capacity；planetary boundaries；biophysical process；threshold；scale