Département de Biologie, Université de Sherbrooke, Sherbrooke, Québec J1K 2R1, Canada; email:
Forest and Nature Lab, Department of Forest and Water Management, Ghent University, BE-9090 Melle-Gontrode, Belgium.
Annu Rev Plant Biol. 2017 Apr 28;68:563-586. doi: 10.1146/annurev-arplant-042916-040949. Epub 2017 Jan 11.
Plant communities have undergone dramatic changes in recent centuries, although not all such changes fit with the dominant biodiversity-crisis narrative used to describe them. At the global scale, future declines in plant species diversity are highly likely given habitat conversion in the tropics, although few extinctions have been documented for the Anthropocene to date (<0.1%). Nonnative species introductions have greatly increased plant species richness in many regions of the world at the same time that they have led to the creation of new hybrid polyploid species by bringing previously isolated congeners into close contact. At the local scale, conversion of primary vegetation to agriculture has decreased plant diversity, whereas other drivers of change-e.g., climate warming, habitat fragmentation, and nitrogen deposition-have highly context-dependent effects, resulting in a distribution of temporal trends with a mean close to zero. These results prompt a reassessment of how conservation goals are defined and justified.
近年来，植物群落发生了巨大变化，但并非所有这些变化都符合用来描述它们的主导生物多样性危机叙事。在全球范围内，考虑到热带地区的生境转换，未来植物物种多样性很可能会下降，尽管到目前为止，人为世记录到的物种灭绝很少（<0.1%）。在许多地区，外来物种的引入大大增加了植物物种的丰富度，同时也通过使以前隔离的近缘种密切接触，导致了新的杂交多倍体物种的产生。在局部尺度上，原生植被向农业的转化减少了植物多样性，而其他变化驱动因素——例如气候变暖、生境破碎化和氮沉降——具有高度依赖于情境的影响，导致时间趋势的分布平均值接近零。这些结果促使人们重新评估如何定义和证明保护目标的合理性。
