LETTER doi:10.1038/nature19092 Biodiversity at multiple trophic levels is needed for ecosystem multifunctionality Santiago Soliveres1, Fons van der Plas1,2, Peter Manning1,2, Daniel Prati1, Martin M. Gossner3,4, Swen C. Renner5,6, Fabian Alt7, Hartmut Arndt8, Vanessa Baumgartner9, Julia Binkenstein10, Klaus Birkhofer11, Stefan Blaser1, Nico Blüthgen12, Steffen Boch1,13, Stefan Böhm5, Carmen Börschig14, Francois Buscot15,16, Tim Diekötter17, Johannes Heinze18,19, Norbert Hölzel20, Kirsten Jung21, Valentin H. Klaus20, Till Kleinebecker20, Sandra Klemmer15, Jochen Krauss22, Markus Lange3,4,23, E. Kathryn Morris24,25, Jörg Müller18, Yvonne Oelmann7, Jörg Overmann9, Esther Pašalić3,4, Matthias C. Rillig19,25, H. Martin Schaefer26, Michael Schloter27, Barbara Schmitt1, Ingo Schöning3,23, Marion Schrumpf23, Johannes Sikorski9, Stephanie A. Socher28, Emily F. Solly23,29, Ilja Sonnemann30, Elisabeth Sorkau7, Juliane Steckel22, Ingolf Steffan-Dewenter22, Barbara Stempfhuber27, Marco Tschapka21,31, Manfred Türke3,4,16,32, Paul C. Venter8, Christiane N. Weiner12, Wolfgang W. Weisser3,4, Michael Werner22, Catrin Westphal14, Wolfgang Wilcke33, Volkmar Wolters34, Tesfaye Wubet15,16, Susanne Wurst30, Markus Fischer1,2,13 & Eric Allan1,35 Many experiments have shown that loss of biodiversity reduces the functioning as strongly as abiotic conditions and land-use intensity, capacity of ecosystems to provide the multiple services on which extending previous experimental results7,8 to real-world ecosystems. humans depend1,2. However, experiments necessarily simplify Primary producers, herbivorous insects and microbial decomposers the complexity of natural ecosystems and will normally control seem to be particularly important drivers of ecosystem functioning, for other important drivers of ecosystem functioning, such as the as shown by the strong and frequent positive associations of their environment or land use. In addition, existing studies typically focus richness or abundance with multiple ecosystem services. Our results on the diversity of single trophic groups, neglecting the fact that show that multitrophic richness and abundance support ecosystem biodiversity loss occurs across many taxa3,4 and that the functional functioning, and demonstrate that a focus on single groups has led effects of any trophic group may depend on the abundance and to researchers to greatly underestimate the functional importance diversity of others5,6. Here we report analysis of the relationships of biodiversity. between the species richness and abundance of nine trophic groups, Global change is causing species loss across many trophic groups3,4, including 4,600 above- and below-ground taxa, and 14 ecosystem with potential effects on the services that ecosystems provide to services and functions and with their simultaneous provision humans1,2. The functional consequences of a decline in biodiversity (or multifunctionality) in 150 grasslands. We show that high species across multiple trophic groups are hard to predict from studies focus- richness in multiple trophic groups (multitrophic richness) had ing on single taxa, as the functional effects of different groups may stronger positive effects on ecosystem services than richness in complement or oppose each other5,6,9,10. The effects of the diversity any individual trophic group; this includes plant species richness, of plants and microbes are complementary, maximizing rates of the most widely used measure of biodiversity. On average, three nutrient cycling11; plant and herbivore diversity, on the other hand, trophic groups influenced each ecosystem service, with each have opposing effects on biomass stocks10,12,13. Consequently, we know trophic group influencing at least one service. Multitrophic very little about the relative effect of changes in the diversity of different richness was particularly beneficial for ‘regulating’ and ‘cultural’ trophic groups on the provision of individual2,5,6,9,13,14 or multiple services, and for multifunctionality, whereas a change in the (multifunctionality)11,15 ecosystem services. total abundance of species or biomass in multiple trophic groups In addition to decreasing species richness, global change is altering (the multitrophic abundance) positively affected supporting the total abundance (total number of individuals or amount of 4 services. Multitrophic richness and abundance drove ecosystem biomass within communities) of multiple trophic groups . Changes in 1Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland. 2Senckenberg Gesellschaft für Naturforschung, Biodiversity and Climate Research Centre BIK-F, Senckenberganlage 25, 60325 Frankfurt, Germany. 3Institute of Ecology, Friedrich-Schiller-University Jena, Dornburger Straße 159, D-07743 Jena, Germany. 4Technische Universität München, Terrestrial Ecology Research Group, Department of Ecology and Ecosystem Management, School of Life Sciences Weihenstephan, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany. 5Institute of Zoology, University of Natural Resources and Life Science, Gregor-Mendel-Straße 33, 1180 Vienna, Austria. 6Smithsonian Conservation Biology Institute, National Zoological Park, 1500 Remount Road, Front Royal, Virginia 22630, USA. 7Geocology, University of Tuebingen, Ruemelinstr. 19-23, 72070 Tuebingen, Germany. 8University of Cologne, Institute for Zoology, Zülpicher Str. 47b, 50674 Cologne, Germany. 9Leibniz Institute DSMZ German Collection of Microorganisms and Cell Cultures, Inhoffenstr. 7B, 38124 Braunschweig, Germany. 10Chair of Nature Conservation and Landscape Ecology, Faculty of Environment and Natural Resources, University of Freiburg, Tennenbacher Straße 4, 79106 Freiburg, Germany. 11Department of Biology, Lund University, Sölvegatan 35, 22362 Lund, Germany. 12Ecological Networks, Biology, Technische Universität Darmstadt, Schnittspahnstr. 3, 64287 Darmstadt, Germany. 13Botanical Garden, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland. 14Agroecology, Department of Crop Sciences, Georg-August University of Göttingen, Grisebachstr. 6, D-37077, Göttingen, Germany. 15UFZ-Helmholtz Centre for Environmental Research, Department of Soil Ecology, Theodor-Lieser-Straße 4, 06120 Halle (Saale), Germany. 16German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena- Leipzig, Deutscher Platz 5e, D-04103 Leipzig, Germany. 17Department of Landscape Ecology, Kiel University, Olshausenstr. 75, D-24118 Kiel, Germany. 18Biodiversity Research/Systematic Botany, University of Potsdam, Maulbeerallee 1, D-14469 Potsdam, Germany. 19Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), D-14195 Berlin, Germany. 20Institute of Landscape Ecology, University of Münster, Heisenbergstr. 2, 48149 Münster, Germany. 21Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein-Allee 11, 89069 Ulm, Germany. 22Department of Animal Ecology and Tropical Biology, Biocentre, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany. 23Max-Planck Institute for Biogeochemistry, Hans- Knoell-Str. 10, 07745 Jena, Germany. 24Xavier University, Department of Biology, 3800 Victory Parkway, Cincinnati, Ohio 45207, USA. 25Plant Ecology, Institut für Biologie, Freie Universität Berlin, Altensteinstr. 6, D-14195 Berlin, Germany. 26Department of Ecology and Evolutionary Biology, Faculty of Biology, University of Freiburg, Hauptstraße 1, 79104 Freiburg i. Br., Germany. 27Research Unit for Environmental Genomics; Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85758 Oberschleissheim, Germany. 28Department of Ecology and Evolution, Universität Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria. 29Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland. 30Functional Biodiversity, Institute of Biology, Freie Universität Berlin. Königin-Luise-Str. 1-3. D-14195 Berlin, Germany. 31Smithsonian Tropical Research Institute, Balboa, Panama. 32Institute for Biology, Leipzig University, Johannisallee 21, D-04103 Leipzig, Germany. 33Institute of Geography and Geoecology, Karlsruhe Institute of Technology (KIT), Reinhard-Baumeister-Platz 1, 76131 Karlsruhe, Germany. 34Department of Animal Ecology, Justus Liebig University Giessen, Heinrich-Buff-Ring 26-32, D-35392 Giessen, Germany. 35Centre for Development and Environment, University of Bern, Hallerstrasse, 10, 3012 Bern, Switzerland. 00 MONTH 2016 | VOL 000 | NATURE | 1 © 2016 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. RESEARCH LETTER a Multitrophic diversity e abundance could mitigate or exacerbate the functional consequences Multitrophic abundance Primary producers Single trophic diversity Above herbivores 16,17 0.4 Single trophic abundance of species loss by influencing the ability of each trophic group to Plant diversity Detritivores capture resources. However, studies normally focus on the effects 0.2 Above predators 18–20 Plant symbionts of community evenness or of dominant species , whereas the Below herbivores 0 Microb. decomposers simultaneous effects of changes in richness and total abundance on Change in Bacterivores 6,16 ovisioning services the functioning of ecosystems have been largely unexplored . The –0.2 Below predators pr 00.1 0.20.3 relative importance of richness and abundance may depend on the Marginal R2 function or service of interest. Total abundance could be a main driver 0 0.2 0.4 0.6 0.8 1 –0.4 –0.2 0 0.2 0.4 18 of biogeochemical process rates (for example,