DOI: 10.5061/dryad.q428q
title: Data from: Changes in plant, soil and microbes in a typical steppe from simulated grazing: explaining potential change in soil carbon

description: Grazing can directly or indirectly influence carbon (C) inputs, turnover,
 and retention in grassland soil. However, relative to the plant response
 to grazing, belowground biota and process responses are more complex and
 often do not correlate with the aboveground responses. Ungulate grazing
 involves three mechanisms - defoliation (removal of plant shoot tissue),
 dung and urine return, and trampling. An evaluation of the relative roles
 of these mechanisms and their combinations in grazing can explain the
 causes of changes in grassland, thereby explaining the soil carbon
 sequestration in a steppe ecosystem. In this study, we examined the
 changes in plants attributes, soil abiotic characteristics, and the soil
 microbial community in response to mowing (M), dung and urine addition
 (DU), simulated trampling (T), and their combinations by conducting a
 3-year experiment in a steppe ecosystem in Inner Mongolia, China. Most of
 the variation in the grazing effects on grassland was explained by
 defoliation through decreased plant production and soil respiration and
 altered vegetation composition. Dung and urine return was second to
 defoliation in explaining grazing effects on grassland, and lead to
 increasing plant C inputs to the soil, while simultaneously potential loss
 of soil C due to the increase of the abundance of bacteria and soil
 respiration, eventually accelerated soil C cycling. An interaction between
 defoliation and trampling on microbial growth was observed in our study:
 trampling increased the abundance of total bacteria, fungi, and AMF only
 in the no-mowing plots. Trampling led to plant allocation to the
 belowground tissues and increased the abundance of fungi and AMF, which is
 critical for soil carbon sequestration, and trampling with defoliation
 further decreased the abundance of soil microbes, which may decelerate
 soil C cycling and increase its retention time. These results indicate
 that defoliation and dung and urine return play major roles in explaining
 grazing effects on grassland systems, including plant, soil, and microbe
 parameters examined, but the trampling effects and the interaction between
 defoliation and trampling are the two key factors that contribute to
 explaining the overall effects of grazing on soil carbon sequestration in
 a typical steppe ecosystem in Inner Mongolia.
description: Plant
 parametersThe data were collected
 in the field. Excel was used to create the data. SE-standard error,
 Treatment: C- control,DU-dung and urine return; M-mowing; T-trampling;
 DU+M-mowing combined with the addition of dung and urine; M+T-mowing
 combined with trampling; DU+T-trampling combined with the addition of dung
 and urine; DU+M+T-mowing combined with trampling and the addition of dung
 and urineSoil
 parametersThe data were collected
 in the field. Excel was used to create the data. SE-standard error,
 MBC-soil microbial biomass carbon, MBN- soil microbial biomass nitrogen.
 Treatment: C- control,DU-dung and urine return; M-mowing; T-trampling;
 DU+M-mowing combined with the addition of dung and urine; M+T-mowing
 combined with trampling; DU+T-trampling combined with the addition of dung
 and urine; DU+M+T-mowing combined with trampling and the addition of dung
 and urineSoil microbes'
 parametersThe data were collected
 in the field. Excel was used to create the data. SE-standard error,
 Gram+-gram positive bacteria, Gram--gram negative bacteria, AMF-
 arbuscular mycorrhizal fungi, B/F-bacteria to fungi ratio. Treatment: C-
 control,DU-dung and urine return; M-mowing; T-trampling; DU+M-mowing
 combined with the addition of dung and urine; M+T-mowing combined with
 trampling; DU+T-trampling combined with the addition of dung and urine;
 DU+M+T-mowing combined with trampling and the addition of dung and
 urinePCA and RDA analysis
 data sheetThe data were collected
 in the field. Excel was used to create the data. Gram+-gram positive
 bacteria, Gram--gram negative bacteria, AMF- arbuscular mycorrhizal fungi,
 B/F-bacteria to fungi ratio, SOC- soil organic carbon, TN- soil total
 nitrogen, C/N-soil organic carbon to total nitrogen ratio. Treatment: C-
 control,DU-dung and urine return; M-mowing; T-trampling; DU+M-mowing
 combined with the addition of dung and urine; M+T-mowing combined with
 trampling; DU+T-trampling combined with the addition of dung and urine;
 DU+M+T-mowing combined with trampling and the addition of dung and
 urine