1] Department of Ecology, Evolution, and Behavior, University of Minnesota, St Paul, Minnesota 55108, USA [2] Institute of Evolutionary Biology and Environmental Studies, University of Zurich, 8057 Zurich, Switzerland.
Department of Ecology, Evolution, and Behavior, University of Minnesota, St Paul, Minnesota 55108, USA.
Nature. 2014 Apr 24;508(7497):521-5. doi: 10.1038/nature13014. Epub 2014 Feb 16.
Studies of experimental grassland communities have demonstrated that plant diversity can stabilize productivity through species asynchrony, in which decreases in the biomass of some species are compensated for by increases in others. However, it remains unknown whether these findings are relevant to natural ecosystems, especially those for which species diversity is threatened by anthropogenic global change. Here we analyse diversity-stability relationships from 41 grasslands on five continents and examine how these relationships are affected by chronic fertilization, one of the strongest drivers of species loss globally. Unmanipulated communities with more species had greater species asynchrony, resulting in more stable biomass production, generalizing a result from biodiversity experiments to real-world grasslands. However, fertilization weakened the positive effect of diversity on stability. Contrary to expectations, this was not due to species loss after eutrophication but rather to an increase in the temporal variation of productivity in combination with a decrease in species asynchrony in diverse communities. Our results demonstrate separate and synergistic effects of diversity and eutrophication on stability, emphasizing the need to understand how drivers of global change interactively affect the reliable provisioning of ecosystem services in real-world systems.
实验性草地群落的研究表明，植物多样性可以通过物种的非同步性来稳定生产力，即某些物种生物量的减少被其他物种的增加所补偿。然而，目前尚不清楚这些发现是否与自然生态系统有关，特别是那些因人为全球变化而面临物种多样性威胁的生态系统。在这里，我们分析了来自五大洲 41 个草地的多样性-稳定性关系，并研究了这些关系如何受到慢性施肥的影响，慢性施肥是全球物种丧失的最强驱动力之一。未受人为干预的多物种群落具有更高的物种非同步性，从而导致更稳定的生物量生产，将生物多样性实验的结果推广到现实世界的草地。然而，施肥削弱了多样性对稳定性的积极影响。与预期相反，这不是由于富营养化后物种的丧失，而是由于生产力的时间变化增加，以及多样化群落中物种非同步性的降低。我们的研究结果表明多样性和富营养化对稳定性具有单独和协同的影响，强调需要了解全球变化的驱动因素如何相互作用地影响现实系统中生态系统服务的可靠提供。
