Department of Zoology, University of Oxford, Oxford, OX1 3PS, UK.
School of Geography, Earth and Environmental Sciences, University of Plymouth, Plymouth, PL4 8AA, UK.
Ecol Lett. 2018 Jun;21(6):814-825. doi: 10.1111/ele.12944. Epub 2018 Mar 30.
Plants and animals influence biomass production and nutrient cycling in terrestrial ecosystems; however, their relative importance remains unclear. We assessed the extent to which mega-herbivore species controlled plant community composition and nutrient cycling, relative to other factors during and after the Late Quaternary extinction event in Britain and Ireland, when two-thirds of the region's mega-herbivore species went extinct. Warmer temperatures, plant-soil and plant-plant interactions, and reduced burning contributed to the expansion of woody plants and declining nitrogen availability in our five study ecosystems. Shrub biomass was consistently one of the strongest predictors of ecosystem change, equalling or exceeding the effects of other biotic and abiotic factors. In contrast, there was relatively little evidence for mega-herbivore control on plant community composition and nitrogen availability. The ability of plants to determine the fate of terrestrial ecosystems during periods of global environmental change may therefore be greater than previously thought.
植物和动物影响陆地生态系统的生物量生产和养分循环；然而，它们的相对重要性仍不清楚。我们评估了在英国和爱尔兰晚第四纪灭绝事件期间和之后，巨型食草动物物种相对于其他因素控制植物群落组成和养分循环的程度，当时该地区三分之二的巨型食草动物物种灭绝。在我们的五个研究生态系统中，较暖的温度、植物-土壤和植物-植物相互作用以及减少燃烧促进了木本植物的扩张和氮可用性的降低。灌木生物量一直是生态系统变化的最强预测因子之一，与其他生物和非生物因素的影响相当或超过。相比之下，巨型食草动物对植物群落组成和氮可用性的控制相对较少。因此，在全球环境变化时期，植物决定陆地生态系统命运的能力可能比以前认为的要大。
