Biodiversity Increases the Resistance of Ecosystem Productivity to Climate Extremes

Abstract

<p>It remains unclear whether biodiversity buffers ecosystems against climate extremes, which are becoming increasingly frequent worldwide^{<a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref1" id="x-x-ref-link-1" title="Stocker, T. F. et al. IPCC 2013: Summary for Policy Makers (Cambridge Univ. Press, 2013)">1</a>}. Early results suggested that the ecosystem productivity of diverse grassland plant communities was more resistant, changing less during drought, and more resilient, recovering more quickly after drought, than that of depauperate communities^{<a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref2" id="x-x-ref-link-2" title="Tilman, D. & Downing, J. A. Biodiversity and stability in grasslands. Nature 367, 363-365 (1994)">2</a>}. However, subsequent experimental tests produced mixed results^{<a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref3" id="x-x-ref-link-3" title="Pfisterer, A. B. & Schmid, B. Diversity-dependent production can decrease the stability of ecosystem functioning. Nature 416, 84-86 (2002)">3</a>, <a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref4" id="x-x-ref-link-4" title="Caldeira, M. C., Hector, A., Loreau, M. & Pereira, J. S. Species richness, temporal variability and resistance of biomass production in a Mediterranean grassland. Oikos 110, 115-123 (2005)">4</a>, <a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref5" id="x-x-ref-link-5" title="Kahmen, A., Perner, J. & Buchmann, N. Diversity-dependent productivity in semi-natural grasslands following climate perturbations. Funct. Ecol. 19, 594-601 (2005)">5</a>, <a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref6" id="x-x-ref-link-6" title="Steiner, C. F., Long, Z. T., Krumins, J. A. & Morin, P. J. Population and community resilience in multitrophic communities. Ecology 87, 996-1007 (2006)">6</a>, <a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref7" id="x-x-ref-link-7" title="Wang, Y., Yu, S. & Wang, J. Biomass-dependent susceptibility to drought in experimental grassland communities. Ecol. Lett. 10, 401-410 (2007)">7</a>, <a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref8" id="x-x-ref-link-8" title="Ives, A. R. & Carpenter, S. R. Stability and diversity of ecosystems. Science 317, 58-62 (2007)">8</a>, <a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref9" id="x-x-ref-link-9" title="Griffin, J. N. et al. in Biodiversity, Ecosystem Functioning, & Human Wellbeing: An Ecological and Economic Perspective (eds Naeem, S. et al.) Ch. 6 78-93 (Oxford Univ. Press, 2009)">9</a>, <a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref10" id="x-x-ref-link-10" title="van Ruijven, J. & Berendse, F. Diversity enhances community recovery, but not resistance, after drought. J. Ecol. 98, 81-86 (2010)">10</a>, <a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref11" id="x-x-ref-link-11" title="Vogel, A., Scherer-Lorenzen, M. & Weigelt, A. Grassland resistance and resilience after drought depends on management intensity and species richness. PLoS One 7, e36992 (2012)">11</a>, <a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref12" id="x-x-ref-link-12" title="Grossiord, C. et al. Tree diversity does not always improve resistance of forest ecosystems to drought. Proc. Natl Acad. Sci. USA 111, 14812-14815 (2014)">12</a>, <a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref13" id="x-x-ref-link-13" title="Wright, A. J. et al. Flooding disturbances increase resource availability and productivity but reduce stability in diverse plant communities. Nature Commun. 6, 6092 (2015)">13</a>}. Here we use data from 46 experiments that manipulated grassland plant diversity to test whether biodiversity provides resistance during and resilience after climate events. We show that biodiversity increased ecosystem resistance for a broad range of climate events, including wet or dry, moderate or extreme, and brief or prolonged events. Across all studies and climate events, the productivity of low-diversity communities with one or two species changed by approximately 50% during climate events, whereas that of high-diversity communities with 16–32 species was more resistant, changing by only approximately 25%. By a year after each climate event, ecosystem productivity had often fully recovered, or overshot, normal levels of productivity in both high- and low-diversity communities, leading to no detectable dependence of ecosystem resilience on biodiversity. Our results suggest that biodiversity mainly stabilizes ecosystem productivity, and productivity-dependent ecosystem services, by increasing resistance to climate events. Anthropogenic environmental changes that drive biodiversity loss thus seem likely to decrease ecosystem stability^{<a href="http://www.nature.com/nature/journal/vaop/ncurrent/full/nature15374.html#ref14" id="x-x-ref-link-14" title="Hautier, Y. et al. Plant ecology. Anthropogenic environmental changes affect ecosystem stability via biodiversity. Science 348, 336-340 (2015)">14</a>}, and restoration of biodiversity to increase it, mainly by changing the resistance of ecosystem productivity to climate events.</p>