DOI: 10.5061/dryad.dt3nm
title: Data from: Disentangling plant and soil microbial controls on carbon and nitrogen loss in grassland mesocosms

description: 1. It is well known that plant–soil interactions play an important role in
 determining the impact of global change phenomena on biodiversity and
 ecosystem functioning. Little is known, however, about the individual and
 relative importance for carbon (C) and nitrogen (N) cycling of non-random
 changes in plant and soil communities that result from global change
 phenomena, such as fertilization and agricultural intensification. 2. We
 set up a field-based mesocosm experiment in which we re-inoculated soil
 with contrasting microbial communities taken from extensively managed and
 from intensively managed grasslands. In a full-factorial design, we
 subsequently established plant communities representative of intensively
 and extensively managed grasslands and imposed a fertilization treatment.
 We then measured plant biomass and diversity, and leaching of C and N as
 key measures of C and N loss. 3. We hypothesized that non-random changes
 in both microbial and plant communities would impact C and N leaching, but
 via different mechanisms. We predicted that plant communities
 representative of extensively managed grassland would reduce C and N
 leaching directly through increased water or N uptake, or indirectly via
 promoting microbial communities that immobilize C and N, whereas plant
 communities of intensively managed grassland would have the opposite
 effect. We also hypothesized that microbial communities of extensively
 managed grassland would feed back positively to plant diversity and that
 ‘matching’ plant and microbial communities would reduce C and N leaching.
 4. We found that both plant and microbial communities from extensively
 managed grassland reduced C and N leaching, especially when ‘matched’.
 Plant community effects on C and N leaching operated directly through root
 C inputs and N uptake, rather than through changes in soil microbial
 communities. In contrast, microbial communities modified C and N leaching
 both directly by immobilization and indirectly through modifying plant
 community composition. 5. Synthesis. Our results show that changes in
 plant and microbial communities both individually and interactively modify
 C and N loss from grasslands. Moreover, our results suggest that soil
 microbial communities typical of extensively managed grassland might
 counteract, or delay, the negative consequences of fertilization on plant
 diversity and ecosystem functioning.
description: Soil and plants
 2010Contains data for the
 first year of the experiment, including soil analyses immediately after
 inoculation with microbial communities but before planting with plant
 communities, total biomass data for the first harvest (August 2010) and
 biomass data for all individual species for the second harvest (October
 2010). See ReadMe file for variable names and
 descriptions.Soil and plants
 2011Contains data for the
 second and final year of the experiment. This includes all soil and
 vegetation data for the final destructive harvest in October 2011. See
 ReadMe file for names and description of variables.LeachatesThis file contains leachate data for the mesocosms. Leachates were collected non-destructively at 7 dates in 2011. See ReadMe file for names and description of variables.PLFAsThis file contains PLFA profiles for mesocosms, analysed in soil samples from the final destructive harvest on October 2011. See ReadMe file for more information on this file.