气候变化领域集成服务门户(CCPortal): Impact of alpine meadow degradation on soil hydraulic properties over the Qinghai-Tibetan Plateau

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DOI	10.1016/j.jhydrol.2012.11.058
	Impact of alpine meadow degradation on soil hydraulic properties over the Qinghai-Tibetan Plateau
	Zeng, Chen; Zhang, Fan; Wang, Quanjiu; Chen, Yingying; Joswiak, Daniel R.
通讯作者	Zeng, C (通讯作者)
发表日期	2013
ISSN	0022-1694
EISSN	1879-2707
起始页码	148
结束页码	156
卷号	478
英文摘要	Alpine meadow soil is an important ecosystem component of the Qinghai-Tibetan Plateau. However, the alpine meadow soil is undergoing serious degradation mainly due to global climate change, overgrazing, human activities and rodents. In this paper, spatial sequencing was chosen over time succession sequencing to study the changes of soil hydraulic properties under different degrees of alpine meadow degradation. Soil saturated hydraulic conductivity (Ks) and Gardner alpha both at the surface and at 40-50 cm depth were investigated in the field using tension infiltrometers. Soil physical and chemical properties, together with the root index at 0-10 cm and 40-50 cm soil layer depths were also analyzed. Pearson correlations were adopted to study the relationships among the investigated factors and principal component analysis was performed to identify the dominant factor. Results show that with increasing degree of degradation, soil sand content increased while soil Ks and Gardner alpha as well as soil clay content, soil porosity decreased in the 0-10 cm soil layers, and organic matter and root gravimetric density decreased in both the 0-10 cm and 40-50 cm soil layers. However, soil moisture showed no significant changes with increasing degradation. With decreasing pressure head, soil unsaturated hydraulic conductivity reduced more slowly under degraded conditions than non-degraded conditions. Soil Ks and Gardner alpha were significantly correlated (P = 0.01) with bulk density, soil porosity, soil organic matter and root gravimetric density. Among these, soil porosity is the dominant factor explaining about 90% of the variability in total infiltration flow. Under non-degraded conditions, the infiltration flow principally depended on the presence of macropores. With increasing degree of degradation, soil macropores quickly changed to mesopores or micropores. The proportion of total infiltration flow through macropores and mesopores significantly decreased with the most substantial decrease observed for the macropores in the 0-10 cm soil layer. The substantial decrease of macropores caused a cut in soil moisture and hydraulic conductivity. This study improves the understanding and prediction of alpine meadow soil and ecosystem changes and provides guidelines for improving water flow modeling under the background of global climate change over the Qinghai-Tibetan Plateau and similar regions. (C) 2012 Elsevier B.V. All rights reserved.
关键词	PHYSICAL-PROPERTIES SPATIAL VARIABILITY ORGANIC-MATTER YELLOW-RIVER LAND-USE CONDUCTIVITY WATER TILLAGE CARBON TRANSPORT
英文关键词	Alpine meadow soil; Degradation; Basic soil property; Hydraulic property; Qinghai-Tibetan Plateau
语种	英语
WOS研究方向	Engineering ; Geology ; Water Resources
WOS类目	Engineering, Civil ; Geosciences, Multidisciplinary ; Water Resources
WOS记录号	WOS:000315612700012
来源期刊	JOURNAL OF HYDROLOGY
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/258139
推荐引用方式 GB/T 7714	Zeng, Chen,Zhang, Fan,Wang, Quanjiu,et al. Impact of alpine meadow degradation on soil hydraulic properties over the Qinghai-Tibetan Plateau[J]. 中国科学院青藏高原研究所,2013,478.
APA	Zeng, Chen,Zhang, Fan,Wang, Quanjiu,Chen, Yingying,&Joswiak, Daniel R..(2013).Impact of alpine meadow degradation on soil hydraulic properties over the Qinghai-Tibetan Plateau.JOURNAL OF HYDROLOGY,478.
MLA	Zeng, Chen,et al."Impact of alpine meadow degradation on soil hydraulic properties over the Qinghai-Tibetan Plateau".JOURNAL OF HYDROLOGY 478(2013).