title: Plant diversity and functional groups affect Si and Ca pools in aboveground biomass of grassland systems.
abstract: Plant diversity is an important driver of nitrogen and phosphorus stocks in aboveground plant biomass of grassland ecosystems, but plant diversity effects on other elements also important for plant growth are less understood. We tested whether plant species richness, functional group richness or the presence/absence of particular plant functional groups influences the Si and Ca concentrations (mmol g(-1)) and stocks (mmol m(-2)) in aboveground plant biomass in a large grassland biodiversity experiment (Jena Experiment). In the experiment including 60 temperate grassland species, plant diversity was manipulated as sown species richness (1, 2, 4, 8, 16) and richness and identity of plant functional groups (1-4; grasses, small herbs, tall herbs, legumes). We found positive species richness effects on Si as well as Ca stocks that were attributable to increased biomass production. The presence of particular functional groups was the most important factor explaining variation in aboveground Si and Ca stocks (mmol m(-2)). Grass presence increased the Si stocks by 140 % and legume presence increased the Ca stock by 230 %. Both the presence of specific plant functional groups and species diversity altered Si and Ca stocks, whereas Si and Ca concentration were affected mostly by the presence of specific plant functional groups. However, we found a negative effect of species diversity on Si and Ca accumulation, by calculating the deviation between mixtures and mixture biomass proportions, but in monoculture concentrations. These changes may in turn affect ecosystem processes such as plant litter decomposition and nutrient cycling in grasslands.
authors.affiliation: Institute of General Ecology and Environmental Protection, Technische Universität Dresden, Pienner Straße 19, 01737, Tharandt, Germany. Joerg.Schaller@uni-bayreuth.de.|Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University Bayreuth, Universitätsstraße 30, 95447, Bayreuth, Germany. Joerg.Schaller@uni-bayreuth.de.
authors.forename: Jörg
authors.initials: J
authors.lastname: Schaller
authors.affiliation: Department of Physiological Diversity, UFZ, Helmholtz Centre for Environmental Research, Permoserstraße 15, 04138, Leipzig, Germany.|German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103, Leipzig, Germany.
authors.forename: Christiane
authors.initials: C
authors.lastname: Roscher
authors.affiliation: Institute for Chemistry and Biology of the Marine Environment, Carl-von Ossietzky University, 26111, Oldenburg, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Hillebrand
authors.affiliation: German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103, Leipzig, Germany.|Department for Systematic Botany and Functional Biodiversity, University of Leipzig, Johannisallee 21-23, 04103, Leipzig, Germany.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Weigelt
authors.affiliation: Geoecology, University of Tuebingen, Rümelinstraße 19-23, 72070, Tübingen, Germany.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Oelmann
authors.affiliation: Institute of Geography and Geoecology, Karlsruhe Institute of Technology (KIT), Reinhard-Baumeister-Platz 1, 76131, Karlsruhe, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wilcke
authors.affiliation: Institute of Ecology, University of Jena, Dornburger Straße 159, 07743, Jena, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Ebeling
authors.affiliation: Department of Ecology and Ecosystem Management, School of Life Sciences Weihenstephan, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85350, Freising, Germany.
authors.forename: Wolfgang W
authors.initials: WW
authors.lastname: Weisser
mesh_terms: D044822:Biodiversity; D018533:Biomass; D017753:Ecosystem; D065948:Grassland; D063245:Plant Development; D006109:Poaceae
keywords: Calcium; Grasses; Jena Experiment; Legumes; Nutrient cycling; Plant diversity; Silicon