气候变化领域集成服务门户(CCPortal): Warming and grazing affect soil labile carbon and nitrogen pools differently in an alpine meadow of the Qinghai-Tibet Plateau in China

CCPortal

DOI	10.1007/s11368-011-0388-6
	Warming and grazing affect soil labile carbon and nitrogen pools differently in an alpine meadow of the Qinghai-Tibet Plateau in China
	Rui, Yichao; Wang, Shiping; Xu, Zhihong; Wang, Yanfen; Chen, Chengrong; Zhou, Xiaoqi; Kang, Xiaoming; Lu, Shunbao; Hu, Yigang; Lin, Qiaoyan; Luo, Caiyun
通讯作者	Wang, YF (通讯作者)
发表日期	2011
ISSN	1439-0108
EISSN	1614-7480
起始页码	903
结束页码	914
卷号	11 期号:6
英文摘要	Small but highly bioactive labile carbon (C) and nitrogen (N) pools are of great importance in controlling terrestrial C and N fluxes, whilst long-term C and N storage is determined by less labile but relatively large sizes of C and N pools. Little information is available about the effects of global warming and grazing on different forms of C and N pools in the Qinghai-Tibet Plateau of China. The aim of this study was to investigate the effects of warming and grazing on the sizes of different soil labile C and N pools and N transformation in this region. A free-air temperature enhancement system in a controlled warming-grazing experiment had been implemented since May 2006. Infrared heaters were used to manipulate temperature, and a moderate grazing intensity was simulated by Tibetan sheep. After 3 years' warming, soil samples were taken from the four treatment plots: no warming with no grazing; no warming with grazing; warming with no grazing; and warming with grazing. Concentrations of inorganic N in the 40-cm soil profiles were measured by a flow injection analyser. Microbial biomass C (MBC) and microbial biomass N (MBN) were measured by the fumigation-extraction method, and soluble organic C (SOC) and soluble organic N (SON) were determined by high-temperature catalytic oxidation. Total N (TN), C isotope composition (delta C-13) and N isotope composition (delta N-15) were determined using an isotope ratio mass spectrometer. Net N transformation under low temperature was studied in a laboratory incubation experiment. Warming and grazing treatments affected soil C and N pools differently, and these effects varied with soil depth. Warming significantly increased TN, MBC, MBN, and SON and decreased delta C-13 at the 10-20 and 20-30 cm soil depths, whilst grazing generally decreased SON at the 10-20 and 20-30 cm, and MBC at 20-30 cm. At the 0-10 cm depth, neither warming nor grazing alone affects these soil parameters significantly, indicating that there could be considerable perturbation on the soil surface. However, grazing alone increased NO (3) (-) -N, total inorganic N, SOC and delta N-15 at the 0-10 cm depth. Incubated at 4A degrees C, warming (particularly with grazing) led to net immobilization of N, but no-warming treatments led to net N mineralization, whilst nitrification was strong across all these treatments. Correlations between MBC and SOC, and TN and MBN or SON were positive. However, SON was less well correlated with TN and MBN compared with the highly positive correlations between SOC and MBC. It is clearly demonstrated that warming and grazing affected labile C and N pools significantly, but differently after 3 years' treatments: Warming tended to enlarge labile C and N pools through increased litter inputs, whilst grazing tended to increase inorganic N pools, decrease SON and accelerate N cycling. Grazing might modify the mode that warming affected soil C and N pools through its strong impacts on microbial processes and N cycling. These results suggested that interactive effects of warming and grazing on C and N pools might have significant implications for the long-term C and N storage and productivity of alpine meadow ecosystem in the Qinghai-Tibet Plateau of China.
关键词	HOOP PINE PLANTATIONS SOLUBLE ORGANIC NITROGEN SIMULATED CLIMATE-CHANGE LITTER MASS-LOSS MICROBIAL BIOMASS ISOTOPE DISCRIMINATION RESIDUE MANAGEMENT TALLGRASS PRAIRIE EXTRACTION METHOD HARVEST RESIDUES
英文关键词	Alpine meadow; Carbon cycling; Grazing; Nitrogen cycling; Warming
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Agriculture
WOS类目	Environmental Sciences ; Soil Science
WOS记录号	WOS:000294065600003
来源期刊	JOURNAL OF SOILS AND SEDIMENTS
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/257899
推荐引用方式 GB/T 7714	Rui, Yichao,Wang, Shiping,Xu, Zhihong,et al. Warming and grazing affect soil labile carbon and nitrogen pools differently in an alpine meadow of the Qinghai-Tibet Plateau in China[J]. 中国科学院青藏高原研究所,2011,11(6).
APA	Rui, Yichao.,Wang, Shiping.,Xu, Zhihong.,Wang, Yanfen.,Chen, Chengrong.,...&Luo, Caiyun.(2011).Warming and grazing affect soil labile carbon and nitrogen pools differently in an alpine meadow of the Qinghai-Tibet Plateau in China.JOURNAL OF SOILS AND SEDIMENTS,11(6).
MLA	Rui, Yichao,et al."Warming and grazing affect soil labile carbon and nitrogen pools differently in an alpine meadow of the Qinghai-Tibet Plateau in China".JOURNAL OF SOILS AND SEDIMENTS 11.6(2011).