Ecoinformatics & Biodiversity Group, Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark.
Am J Bot. 2013 Jul;100(7):1266-86. doi: 10.3732/ajb.1200469. Epub 2013 Jun 10.
Near-future climate changes are likely to elicit major vegetation changes. Disequilibrium dynamics, which occur when vegetation comes out of equilibrium with climate, are potentially a key facet of these. Understanding these dynamics is crucial for making accurate predictions, informing conservation planning, and understanding likely changes in ecosystem function on time scales relevant to society. However, many predictive studies have instead focused on equilibrium end-points with little consideration of the transient trajectories.
We review what we should expect in terms of disequilibrium vegetation dynamics over the next 50-200 yr, covering a broad range of research fields including paleoecology, macroecology, landscape ecology, vegetation science, plant ecology, invasion biology, global change biology, and ecosystem ecology.
The expected climate changes are likely to induce marked vegetation disequilibrium with climate at both leading and trailing edges, with leading-edge disequilibrium dynamics due to lags in migration at continental to landscape scales, in local population build-up and succession, in local evolutionary responses, and in ecosystem development, and trailing-edge disequilibrium dynamics involving delayed local extinctions and slow losses of ecosystem structural components. Interactions with habitat loss and invasive pests and pathogens are likely to further contribute to disequilibrium dynamics. Predictive modeling and climate-change experiments are increasingly representing disequilibrium dynamics, but with scope for improvement.
The likely pervasiveness and complexity of vegetation disequilibrium is a major challenge for forecasting ecological dynamics and, combined with the high ecological importance of vegetation, also constitutes a major challenge for future nature conservation.
未来气候变化很可能引起主要植被变化。当植被与气候失去平衡时，就会出现不平衡动态，这可能是这些变化的一个关键方面。了解这些动态对于做出准确预测、为保护规划提供信息以及及时了解生态系统功能可能发生的变化至关重要。然而，许多预测性研究更多地关注了平衡的终点，而很少考虑瞬态轨迹。
我们回顾了在未来 50-200 年内，我们应该期望看到什么样的非平衡植被动态，涵盖了包括古生态学、宏观生态学、景观生态学、植被科学、植物生态学、入侵生物学、全球变化生物学和生态系统生态学在内的广泛研究领域。
预期的气候变化很可能在植被与气候的前沿和尾缘引起明显的非平衡，前沿的非平衡动态是由于大陆到景观尺度上的迁移滞后、局部种群的建立和演替、局部进化响应以及生态系统发育的滞后，尾缘的非平衡动态则涉及到延迟的局部灭绝和生态系统结构成分的缓慢丧失。与栖息地丧失和入侵性害虫和病原体的相互作用可能会进一步导致非平衡动态。预测建模和气候变化实验越来越多地代表了非平衡动态，但仍有改进的空间。
植被非平衡的普遍性和复杂性很可能是预测生态动态的主要挑战，再加上植被对生态的重要性，这也构成了未来自然保护的主要挑战。
