动态生态位:构建群落生态学理论的新框架

Dynamic niche: a new foundation for rebuilding theory of community ecology

生态学研究的宗旨是澄清有机体与生物和非生物环境之间的关系.作为生态学研究的基石,生态位概念的提出用以刻画物种的生态学意义,量化其对环境的需求及影响,从而揭示调控物种分布、群落构建、食物网动态等生态学过程的机理.生态位概念发展已有百年历史,但人们对其内涵、外延等依然不甚了解,不知如何量化,生态位相关理论面临严峻考验.为此,本文简要追溯生态位概念发展的主要历程和脉络,梳理生态位概念与竞争排除、物种共存和群落构建等群落生态学核心理论之间的关系;从生物与环境互馈演化的视角,再思生态位何以能解释几乎所有的生态学现象,却又难预测任何机理和模式.本文认为生态位不仅是物种生态学作用和影响的体现、是群落动态的驱动因素,更是有机体适应群落环境的结果;是理解生态学规律的必要概念框架,却难以成为解析方法.进而提出动态生态位(dynamic niche)概念框架,以整合有机体属性变化、生态-演化互馈以及随机过程对物种适合度动态和群落构建的重要影响,更新生态位概念,为重构群落生态学理论铺垫基础.

Ecology aims to elucidate how organisms interact with other organisms and their environment. As a fundamental concept of ecological research, the term ecological niche was coined to measure the ecological significance of a species in terms of speciesspecific attributes in relation to the acquisition of environmental resources and impact on the environment. By quantifying species niche, ecologists intended to formulate general rules for controlling various ecological processes, such as species distribution,community assembly, dynamics of the food web structure, and functioning. Over the course of a century, the concept of ecological niche has evolved;however, there is limited information about its essence and meaning. Furthermore, we lack knowledge about its quantification in practice, which means that niche-based theories are faced with significant challenges. Hence, we briefly reviewed the evolutionary history of the niche concept and highlighted its fundamental importance in building the theory of community ecology,such as competition exclusion, species coexistence, and community assembly. From the perspective of feedback dynamics between organisms and the environment, we rethink why the ecological niche can be used to explain various existing patterns but predict nearly nothing. We draw a conclusion that ecological niche not only measures the ecological significance of species that drives community dynamics but also presents it as an emerging consequence of the adaptation of species to the community environment.Moreover, it is essentially a conceptual framework, instead of an analytical approach, for understanding ecological rules. By reconciling the perspectives of reductionism and holism, we propose a conceptual framework for a dynamic niche that considers the importance of change in organism attributes, eco-evolutionary feedback, and stochastic processes on the dynamics of species fitness and community assembly. By updating the classical niche concept into a dynamic one, we aim to establish the foundation for the revision of theories of community ecology.