当前位置： SCI文献检索 > GLOBAL CHANGE BIOLOGY期刊下所有文献 > Carbon storage capacity of semi-arid grassland soils and sequestration potentials in northern China.

Carbon storage capacity of semi-arid grassland soils and sequestration potentials in northern China.

Abstract：

:Organic carbon (OC) sequestration in degraded semi-arid environments by improved soil management is assumed to contribute substantially to climate change mitigation. However, information about the soil organic carbon (SOC) sequestration potential in steppe soils and their current saturation status remains unknown. In this study, we estimated the OC storage capacity of semi-arid grassland soils on the basis of remote, natural steppe fragments in northern China. Based on the maximum OC saturation of silt and clay particles <20 μm, OC sequestration potentials of degraded steppe soils (grazing land, arable land, eroded areas) were estimated. The analysis of natural grassland soils revealed a strong linear regression between the proportion of the fine fraction and its OC content, confirming the importance of silt and clay particles for OC stabilization in steppe soils. This relationship was similar to derived regressions in temperate and tropical soils but on a lower level, probably due to a lower C input and different clay mineralogy. In relation to the estimated OC storage capacity, degraded steppe soils showed a high OC saturation of 78-85% despite massive SOC losses due to unsustainable land use. As a result, the potential of degraded grassland soils to sequester additional OC was generally low. This can be related to a relatively high contribution of labile SOC, which is preferentially lost in the course of soil degradation. Moreover, wind erosion leads to substantial loss of silt and clay particles and consequently results in a direct loss of the ability to stabilize additional OC. Our findings indicate that the SOC loss in semi-arid environments induced by intensive land use is largely irreversible. Observed SOC increases after improved land management mainly result in an accumulation of labile SOC prone to land use/climate changes and therefore cannot be regarded as contribution to long-term OC sequestration.

journal_name

Glob Chang Biol

journal_title

Global change biology

authors

Wiesmeier M,Munro S,Barthold F,Steffens M,Schad P,Kögel-Knabner I

doi

10.1111/gcb.12957

subject

Has Abstract

pub_date

2015-10-01 00:00:00

pages

3836-45

issue

eissn

1354-1013

issn

1365-2486

journal_volume

pub_type

杂志文章

在线工具

Carbon storage capacity of semi-arid grassland soils and sequestration potentials in northern China.