The vertical distribution and control of microbial necromass carbon in forest soils

Global Ecology and Biogeography - Tập 29 Số 10 - Trang 1829-1839 - 2020
Xiangyin Ni1, Shu Liao1, Siyi Tan1, Yan Peng2, Dingyi Wang1, Kai Yue3,1, Fuzhong Wu1, Yusheng Yang1
1Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China
2Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
3Center for Biodiversity Dynamics in a Changing Word (BIOCHANGE), Section for Ecoinformatics and Biodiversity, Department of Biology, Aarhus University, Aarhus, Denmark

Tóm tắt

AbstractAimForest soils contain large amounts of terrestrial organic carbon (C), but the formation pathway of soil organic C (SOC) remains unclear. Recent evidence suggests that microbial necromass is a significant source of SOC, yet a global quantitative assessment across the whole soil profile is lacking. We aimed to assess the vertical distribution and control of microbial‐derived SOC in forest soils.LocationGlobal forests.Time period1996–2019.Major taxa studiedSoil microbial necromass carbon.MethodsWe evaluated the proportions of fungal and bacterial necromass C in total SOC in the litter layer, O horizon soil, and various depths of mineral soil in forests using microbial biomarker (glucosamine and muramic acid) data.ResultsThe total microbial necromass C increased significantly with soil depth, ranging from 30% of SOC in O horizon soil to 62% of SOC in mineral soils below 50 cm. However, only bacterial necromass C followed this increasing trend with soil depth; fungal necromass C showed little variation across the whole soil profile. Higher fungal and bacterial necromass C was observed in soils with lower C/N ratios and smaller aggregate sizes. Soil C/N ratio and microbial biomass C dominantly determined microbial necromass C in surface soil (above 20 cm), but soil clay content was the primary factor in subsoil (below 20 cm).Main conclusionsMicrobial necromass C accounted for high percentages of the total SOC in forest soils (particularly at depths >20 cm), but its long‐term stabilization may be governed by different mechanisms at different soil horizons. Substrate quality regulates microbial activity and then controls biomass turnover in surface soil, while aggregate occlusion facilitates mineral protection of microbial necromass C in subsoil. These differential controls of microbial‐derived organic C could be applied in Earth system studies for predicting soil organic C dynamics in forests.

Từ khóa


Tài liệu tham khảo

10.1016/j.soilbio.2005.09.002

10.1038/s41586-018-0386-6

10.1038/s41586-018-0328-3

10.1007/s10533-012-9822-0

10.1021/acs.est.8b06807

10.1126/science.1231923

10.1038/ngeo2520

10.1111/gcb.12113

10.1038/ngeo2516

10.1111/j.1365-2486.2012.02665.x

10.1016/j.soilbio.2007.03.020

10.1007/s10533-016-0191-y

10.1111/gcb.12374

10.1111/gcb.13237

10.1038/s41586-019-1280-6

10.1016/j.soilbio.2019.107660

10.1007/s00374-018-1288-3

10.1016/j.soilbio.2018.04.014

10.1038/ncomms13630

10.1016/j.soilbio.2016.08.011

10.1038/nature16069

10.1016/j.soilbio.2018.04.019

10.1111/gcb.14781

10.1007/s10533-010-9525-3

10.1038/nmicrobiol.2017.105

10.1038/s41467-018-05891-1

10.1007/s10533-011-9658-z

10.1016/j.soilbio.2020.107762

10.1016/j.soilbio.2016.04.001

10.1126/science.aal1319

10.1007/s00374-016-1161-1

10.1126/sciadv.aau1218

10.1007/s11104-010-0391-5

10.1111/geb.12070

10.1111/gcb.14482

10.1016/j.soilbio.2016.01.016

10.1126/science.1249534

10.1016/j.soilbio.2019.107687

10.1128/AEM.00324-19

10.1111/geb.12029

10.1016/0038-0717(96)00117-4

10.1016/j.soilbio.2019.05.023

Thông tin
Thông tin xuất bản

Global Ecology and Biogeography

Tập 29 Số 10

1829-1839

Thông tin tác giả