气候变化领域集成服务门户(CCPortal): Mechanisms influencing physically sequestered soil carbon in temperate restored grasslands in South Africa and North America

CCPortal

DOI	10.1007/s10533-021-00774-y
	Mechanisms influencing physically sequestered soil carbon in temperate restored grasslands in South Africa and North America
	Scott D.A.; Bach E.M.; Du Preez C.C.; Six J.; Baer S.G.
发表日期	2021
ISSN	1682563
英文摘要	Sequestering carbon (C) into stable soil pools has potential to mitigate increasing atmospheric carbon dioxide concentrations. Carbon accrues in grassland soil restored from cultivation, but the amount of physically protected C (here measured as microaggregate-within-macroaggregate C) and predominant mechanisms of accrual are not well understood. We modeled the rate of physically protected carbon accrued in three mesic temperate perennial restored grasslands from cross-continental regions using datasets with a wide range of restoration ages from northeast Kansas, USA; southeast Nebraska, USA; and northeast Free State, South Africa. Further, we investigated major controls on the amount of physically protected C in each site using structural equation modeling. Variables in the structural equation model were root biomass, root C:N ratio, soil structure (indicated by bulk density, percent of macroaggregates on a per whole soil mass basis, and percent of microaggregate-within-macroaggregates on a per macroaggregate mass basis), microbial composition (indicated by microbial biomass C, total phospholipid fatty acid [PLFA] biomass, and PLFA biomass of arbuscular mycorrhizae fungi [AMF] biomass), and microaggregate-within-macroaggregate C on a per whole soil mass basis. Across all sites, physically protected C accrued at a rate of 16 ± 5 g m−2 year−1. Data from South Africa fit an a priori metamodel developed for northeast KS that hypothesized physically protected C could be explained as a function of microbial composition, soil structure, root C:N ratio, and root biomass (listed in order of strength of direct effect on physically protected C). In contrast to the model-based hypothesis, root C:N ratio was the strongest influence (negative) on physically protected C in South Africa. The lesser effect of AMF on physically protected C in South Africa was consistent with lower AMF biomass in arid environments. The hypothesized model did not fit southeast Nebraska data possibly due to high (~ 30%) clay content. Overall, these results suggest that physically protected C in soil with moderate amounts of clay (more than 10% and less than 30%) can be predicted with knowledge of roots (biomass and C:N ratio), microbial biomass, and soil aggregation. © 2021, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
英文关键词	Arbuscular mycorrhizal fungi; Conservation Reserve Program; Microaggregate‐within‐macroaggregate; Microbial biomass; Roots; Soil organic matter; Soil structure
语种	英语
来源期刊	Biogeochemistry
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/184650
作者单位	Ronin Institute, 127 Haddon Pl, Montclair, NJ, United States; The Nature Conservancy, Nachusa Grasslands, 8772 S Lowden Rd, Franklin Grove, IL 61031, United States; Department of Soil, Crop and Climate Sciences, University of the Free State, Nelson Mandela Dr, Bloemfontein, 9301, South Africa; Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland; Department of Ecology and Evolutionary Biology, Kansas Biological Survey, University of Kansas, Lawrence, KS, United States
推荐引用方式 GB/T 7714	Scott D.A.,Bach E.M.,Du Preez C.C.,et al. Mechanisms influencing physically sequestered soil carbon in temperate restored grasslands in South Africa and North America[J],2021.
APA	Scott D.A.,Bach E.M.,Du Preez C.C.,Six J.,&Baer S.G..(2021).Mechanisms influencing physically sequestered soil carbon in temperate restored grasslands in South Africa and North America.Biogeochemistry.
MLA	Scott D.A.,et al."Mechanisms influencing physically sequestered soil carbon in temperate restored grasslands in South Africa and North America".Biogeochemistry (2021).