DOI: 10.5061/dryad.p83h7
title: Data from: Plant species richness promotes soil carbon and nitrogen stocks in grasslands without legumes

description: 1. The storage of carbon (C) and nitrogen (N) in soil are important
 ecosystem functions. Grassland biodiversity experiments have shown a
 positive effect of plant diversity on soil C and N storage. However, these
 experiments all included legumes, which constitute an important N input
 through N2-fixation. Indeed, the results of these experiments suggest that
 N2-fixation by legumes is a major driver of soil C and N storage. 2. We
 studied whether plant diversity affects soil C and N storage in the
 absence of legumes. In an 11-years grassland biodiversity experiment
 without legumes, we measured soil C and N stocks. We further determined
 above-ground biomass productivity, standing root biomass, soil organic
 matter decomposition and N mineralization rates to understand the
 mechanisms underlying the change in soil C and N stocks in relation to
 plant diversity and their feedbacks to plant productivity. 3. We found
 that soil C and N stocks increased by 18 and 16% in eight-species mixtures
 compared to the average of monocultures of the same species, respectively.
 Increased soil C and N stocks were mainly driven by increased C input and
 N retention, resulting from enhanced plant productivity, which surpassed
 enhanced C loss from decomposition. Importantly, higher soil C and N
 stocks were associated with enhanced soil N mineralization rates, which
 can explain the strengthening of the positive diversity-productivity
 relationship observed in the last years of the experiment. 4. Synthesis:
 We demonstrated that also in the absence of legumes plant species richness
 promotes soil carbon (C) and nitrogen (N) stocks via increased plant
 productivity. In turn, enhanced soil C and N stocks showed a positive
 feedback to plant productivity via enhanced N mineralization, which could
 further accelerate soil C and N storage in the long term.
description: Plant and soil data from
 the last year of the biodiversity experimentData from: Wen-feng
 Cong, Jasper van Ruijven, Liesje Mommer, Gerlinde De Deyn, Frank Berendse
 and Ellis Hoffland. (2014) Plant species richness promotes soil carbon and
 nitrogen stocks in grasslands without legumes. Data were collected in the
 11-year grassland biodiversity experiment in Wageningen, the Netherlands,
 in 2010 and 2011. Abbreviated headlines are as follows: “”BLK”= block;
 “PT”= plot; "SR" = plant species richness; “MI” = monoculture
 identity (Ac = Agrostis capillaris; Ao = Anthoxanthum odoratum; Cj =
 Centaurea jacea; Fr = Festuca rubra; Hl = Holcus lanatus; Lv =
 Leucanthemum vulgare; Pl = Plantago lanceolata; Ra = Rumex acetosa);
 "AAB" = average aboveground biomass from 2000 to 2010 (g m-2);
 "RB" = standing root biomass (g fresh weight m-2) up to 50 cm
 depth in June 2010; "CS" = soil carbon stocks (g C m-2) in April
 2011; "NS" = soil nitrogen stocks (g N m-2) in April 2011.
 "CD" = soil organic carbon decomposition (mg CO2-C kg-1 soil)
 measured in soil collected in April 2011; "NM" = potential net N
 mineralization rate (µg N kg-1 soil day-1) measured in soil collected in
 April 2011.data
 file.csv