气候变化领域集成服务门户(CCPortal): Changes of soil properties regulate the soil organic carbon loss with grassland degradation on the Qinghai-Tibet Plateau

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DOI	10.1016/j.ecolind.2018.05.047
	Changes of soil properties regulate the soil organic carbon loss with grassland degradation on the Qinghai-Tibet Plateau
	Peng Fei; Xue Xian; You Quangang; Huang Cuihua; Dong Siyang; Liao Jie; Duan Hanchen; Tsunekawa, Atsushi; Wang Tao
发表日期	2018
ISSN	1470-160X
EISSN	1872-7034
卷号	93
英文摘要	Grassland in the Qinghai-Tibet Plateau (QTP) provides tremendous carbon (C) sinks and is the important ground for grazing. Grassland degradation, the loss of plant coverage and the emergence of sand activities, results in substantial reduction in soil organic carbon (SOC). To demonstrate the pattern of SOC loss and to elucidate underlying mechanisms, vegetation, soil microclimate, soil properties and respiration of grasslands with different degradation severity over the QTP were investigated. The survey and laboratory data were analyzed by three structural equation modeling (SEM) analyses, which based on three conceptual understandings. The black box model (M1) directly related the abiotic and biotic factors to SOC without consideration of any mechanisms. The biological understanding model (M2) developed the structure of SEM mainly considering ecological processes that regulate the soil SOC. The overall model (M3) developed the SEM structure with the inclusion of both physical and biological processes. Soil moisture (theta), the above and the below-ground plant productivity, and SOC significantly decreased while soil temperature (T-soil) maintained with the development of land degradation. All the three models successfully fitted the data with R-2 about 0.50. Significant pathways from latent variables to SOC were only observed from soil microclimate and soil properties in the Ml. In the M2, three mechanisms can explain the SOC change. The decrease in theta and the consequent adverse effect on soil respiration suggest suppressed C output through microbial decomposition, thus lead to the less SOC loss. The decline in aboveground net primary productivity (ANPP) resulted from a decrease in coverage or due to the change in relative abundance of sedge, forbs, and grass directly or indirectly reduced the C input, and finally lead to the 40-50% loss in SOC. In the M3, only the change in soil properties can explain the SOC reduction. Our results suggest that changes in soil abiotic factors like soil bulk density and pH are the primary factors control the SOC change with land degradation.
关键词	Landdegradation Qinghai-Tibet plateau Soil organic carbon Structural equation modeling Desertification
学科领域	Biodiversity & Conservation; Environmental Sciences & Ecology
语种	英语
WOS研究方向	Biodiversity Conservation ; Environmental Sciences
来源期刊	ECOLOGICAL INDICATORS
来源机构	中国科学院西北生态环境资源研究院
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/111969
作者单位	Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou, Gansu, Peoples R China
推荐引用方式 GB/T 7714	Peng Fei,Xue Xian,You Quangang,et al. Changes of soil properties regulate the soil organic carbon loss with grassland degradation on the Qinghai-Tibet Plateau[J]. 中国科学院西北生态环境资源研究院,2018,93.
APA	Peng Fei.,Xue Xian.,You Quangang.,Huang Cuihua.,Dong Siyang.,...&Wang Tao.(2018).Changes of soil properties regulate the soil organic carbon loss with grassland degradation on the Qinghai-Tibet Plateau.ECOLOGICAL INDICATORS,93.
MLA	Peng Fei,et al."Changes of soil properties regulate the soil organic carbon loss with grassland degradation on the Qinghai-Tibet Plateau".ECOLOGICAL INDICATORS 93(2018).