Leverhulme Centre for Anthropocene Biodiversity, University of York, York, UK.
Department of Biology, University of York, York, United Kingdom.
Glob Chang Biol. 2023 Jul;29(13):3525-3538. doi: 10.1111/gcb.16680. Epub 2023 Apr 12.
Compositional change is a ubiquitous response of ecological communities to environmental drivers of global change, but is often regarded as evidence of declining "biotic integrity" relative to historical baselines. Adaptive compositional change, however, is a foundational idea in evolutionary biology, whereby changes in gene frequencies within species boost population-level fitness, allowing populations to persist as the environment changes. Here, we present an analogous idea for ecological communities based on core concepts of fitness and selection. Changes in community composition (i.e., frequencies of genetic differences among species) in response to environmental change should normally increase the average fitnessof community members. We refer to compositional changes that improve the functional match, or "fit," between organisms' traits and their environment as adaptive community dynamics. Environmental change (e.g., land-use change) commonly reduces the fit between antecedent communities and new environments. Subsequent change in community composition in response to environmental changes, however, should normally increase community-level fit, as the success of at least some constituent species increases. We argue that adaptive community dynamics are likely to improve or maintain ecosystem function (e.g., by maintaining productivity). Adaptive community responses may simultaneously produce some changes that are considered societally desirable (e.g., increased carbon storage) and others that are undesirable (e.g., declines of certain species), just as evolutionary responses within species may be deemed desirable (e.g., evolutionary rescue of an endangered species) or undesirable (e.g., enhanced virulence of an agricultural pest). When assessing possible management interventions, it is important to distinguish between drivers of environmental change (e.g., undesired climate warming) and adaptive community responses, which may generate some desirable outcomes. Efforts to facilitate, accept, or resist ecological change require separate consideration of drivers and responses, and may highlight the need to reconsider preferences for historical baseline communities over communities that are better adapted to the new conditions.
组成变化是生态群落对全球变化环境驱动因素的普遍反应，但通常被视为相对于历史基线“生物完整性”下降的证据。然而，适应性组成变化是进化生物学的一个基本概念，即物种内基因频率的变化提高了种群水平的适应性，使种群能够在环境变化时继续存在。在这里，我们基于适应性的核心概念，提出了一个类似的生态群落概念。群落组成的变化（即物种间遗传差异的频率）对环境变化的响应通常会增加群落成员的平均适应性。我们将那些能够改善生物特征与环境之间功能匹配（即“适应性”）的组成变化称为适应性群落动态。环境变化（例如土地利用变化）通常会降低前群落与新环境之间的适应性。然而，群落组成对环境变化的后续变化通常会增加群落水平的适应性，因为至少一些组成物种的成功增加了。我们认为，适应性群落动态可能会改善或维持生态系统功能（例如，维持生产力）。适应性群落响应可能同时产生一些被认为是社会期望的变化（例如，增加碳储存）和其他不受欢迎的变化（例如，某些物种的减少），就像物种内的进化响应可能被认为是期望的（例如，濒危物种的进化拯救）或不受欢迎的（例如，农业害虫的毒力增强）。在评估可能的管理干预措施时，区分环境变化的驱动因素（例如，不期望的气候变暖）和适应性群落响应非常重要，因为后者可能会产生一些期望的结果。促进、接受或抵制生态变化的努力需要分别考虑驱动因素和响应，并且可能需要重新考虑对历史基线群落的偏好，而不是对适应新条件的群落的偏好。
