流域生态学的发展困境——来自河流景观的启示

随着中国生态环境问题越来越多地呈现出流域特性,流域生态研究的重要性和紧迫性也日渐凸显。整合流域生态研究,形成一个有效的研究体系,流域生态学迄今未能予以实现。通过对"流域生态学"和"河流景观"这两个相近概念提出过程的比较研究,探讨流域生态学发展困境产生的原因,为流域生态研究体系的构建提供思路。分析结果显示流域生态学目前主要存在两个不足:1)因为提出流域生态学概念的关键现实需求不明确,导致难以确定其核心科学问题;2)因为没有相应的流域生态系统概念模型,进而也就难以带动相关研究落实跟进。要推进流域生态学的发展,第一步要做的就是明确流域生态研究体系构建的核心现实需求,并对流域生态系统进行一个概念模型上的相应设计。

Watershed ecology in a dilemma: inspiration from riverine landscape analysis

Watershed ecology is of great importance in China because most ecological and environmental problems occur at a basin-wide scale. However, studies on watershed ecology have not yet synthesized into a unitary framework. The factors causing this dilemma in watershed ecology research are not clear; therefore, it has been difficult to precisely determine how to solve this problem. We hypothesized that this dilemma is rooted in structural defects underlying the concept of watershed ecology. By comparing the concepts of watershed ecology and riverscape, we tried to identify missing links in the formation and development of watershed ecology. The defects of watershed ecology are discussed mainly based on two original papers, "Watershed ecology (in Chinese)", published in Science & Technology Review in 1997 by Cai et al., and "Riverine landscapes: biodiversity patterns, disturbance regimes, and aquatic conservation", published in Biological Conservation in 1998 by Ward, which proposed the concepts of watershed ecology and riverine landscape, respectively. Our review showed that there have been two main defects in the conception and development of watershed ecology. First, there was no clear definition of watershed ecology when the concept was proposed, and there was no identification of core scientific questions. Second, there was no ecosystem model developed at the watershed scale to guide follow-up research on watershed ecology. We suggest defining watershed ecology as an integrative sub-discipline of ecology that is focused on solving complex eco-environmental problems at the watershed scale. A conceptual model describing the spatial heterogeneity and eco-processes of a watershed ecosystem is necessary for building a solid framework of watershed ecology.