DOI: 10.5061/dryad.7338sk6
title: Data from: Linking species abundance and overyielding from experimental communities with niche and fitness characteristics

description: 1) So far, the principal force shaping local plant abundance patterns
 remains unclear. Rarity can result from poor competitive ability or from
 small vegetative or generative reproduction, but also from strong
 self-limitation. The same mechanisms can drive species-specific
 overyielding, i.e. increased species productivity at high community
 diversity. Rare species can then benefit more (i.e. overyield to a larger
 extent) from growing in species-rich communities because of altered
 competitive hierarchies or smaller conspecific frequencies. Here we test
 which mechanism is the most important determinant of species rarity and of
 species-specific productivity across a diversity gradient ranging from
 one- to 60-species plots. 2) For that we measured vegetative growth,
 competitive ability (competitive effect), and negative frequency
 dependence for 49 perennial grassland species from Central Europe. We then
 linked these characteristics with species abundance (measured as species
 biomass from 60-species plots) and with species-specific overyielding in
 The Jena Experiment. 3) Species with higher rates of vegetative growth
 (when grown without neighbors) were also more abundant in the Jena
 Experiment. Larger species-specific overyielding was then associated with
 a stronger negative frequency dependence. As species with greater
 vegetative growth were also more self-limited, larger overyielding in
 species-rich communities was characteristic for common rather than for
 rare species, refuting our initial hypothesis. Finally, path analysis
 indicated that species with poor capacity to suppress neighbors also
 profited more from growing in diverse communities. 4) Synthesis. Our
 results identify key mechanisms driving abundance and productivity of
 species in synthetic communities differing in species richness. While
 vegetative reproduction was closely associated with abundance,
 intraspecific interactions (strength of negative frequency dependence)
 shaped species productivity across a richness gradient. Our study sheds
 light on the abundance patterns of species and their influence on
 community functions, such as biomass production, of species-rich and -poor
 vegetation.
description: DRYADdostalJEcol2018Biomass data were collected in the garden pot experiment from five community types in April 2017. Explanation to column headings: "Target species" = one of 49 species used in the experiment; "Competitor species" = one of two competitor species (Arrhenatherum elatius or Origanum vulgare) used in the experiment; "Community type" = see Fig. 1 in "Dostál P. et al. (2018) Linking species abundance and overyielding from experimental communities with niche and fitness characteristics. Journal or Ecology" for details how five community types were constructed; "#Target individuals planted"= number of target species individuals planted per pot; "#Competitor individuals planted"= number of target species individuals planted per pot; "Inoculum" = identity of species from the first (conditioning) phase serving as a source of soil inoculum in the second experimental phase (HET indicates heterospecific incululum prepared by mixing first-phase soils of all 49 target species); "Target biomass (g, per pot)" = total target species biomass estimated in a pot; "Target biomass (mg, per 1 planted ind.)" = biomass per single planted individual of target species; "Competitor biomass (g, per pot)" = total competitor species biomass estimated in a pot; "Competitor biomass (mg, per 1 planted ind.)" = biomass per single planted individual of competitor species.