气候变化领域集成服务门户(CCPortal): The symbiotic nitrogen fixation by legumes in a legume-companion and a legume-dominant alpine steppe on the central Tibetan Plateau

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DOI	10.1111/1440-1703.12221
	The symbiotic nitrogen fixation by legumes in a legume-companion and a legume-dominant alpine steppe on the central Tibetan Plateau
	Xu-Ri; Dai, Dongxue; Xu, Xingliang
通讯作者	Xu-Ri (通讯作者)
发表日期	2021
ISSN	0912-3814
EISSN	1440-1703
起始页码	545
结束页码	555
卷号	36 期号:3
英文摘要	Symbiotic N-2-fixing plant species occur in many stressful environments, including the central Tibetan Plateau, where the legume species Oxytropis microphylla, Oxytropis glacialis, Astragalus arnoldii occur in the alpine steppe at elevations as high as 4700 m above sea level, either as companion or as dominant species, accounting for 13.91-60.25% of the total aboveground steppe biomass. However, the degree to which they are nutritionally reliant upon symbiotic N-2 fixation is still unclear. We measured the symbiotic nitrogen fixation rate in a legume-companion (LC) and a legume-dominant (LD) alpine steppe community using the N-15 isotope dilution technique. The N derived from the atmosphere (%Ndfa) in the three legume species ranged from 17% to 61% in aboveground tissues and from 70% to 88% in belowground tissues. The N-2 fixation rate was estimated to be 0.25 +/- 0.04 and 1.39 +/- 0.20 g N m(-2) year(-1) for LC and LD based on the aboveground biomass. It was 0.86 +/- 0.04 and 2.77 +/- 0.22 gNm(-2) year(-1) for LC and LD, respectively, when both above and belowground tissues were considered. The total biological nitrogen fixation (BNF) of the alpine steppe on the Tibetan Plateau (ca. 0.7 million km(2)) can then be conservatively estimated at approximately 0.6 T g N year(-1) using the BNF estimate from the LC community. Our findings indicate that estimates based solely on aboveground biomass and LC communities might drastically underestimate the N inputs arising from BNF by legumes to the alpine ecosystem N budget.
英文关键词	N-15 dilution technique; alpine steppe; legume-dominant community; symbiotic nitrogen fixation; Tibetan Plateau
语种	英语
WOS研究方向	Environmental Sciences & Ecology
WOS类目	Ecology
WOS记录号	WOS:000637476200001
来源期刊	ECOLOGICAL RESEARCH
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/260218
推荐引用方式 GB/T 7714	Xu-Ri,Dai, Dongxue,Xu, Xingliang. The symbiotic nitrogen fixation by legumes in a legume-companion and a legume-dominant alpine steppe on the central Tibetan Plateau[J]. 中国科学院青藏高原研究所,2021,36(3).
APA	Xu-Ri,Dai, Dongxue,&Xu, Xingliang.(2021).The symbiotic nitrogen fixation by legumes in a legume-companion and a legume-dominant alpine steppe on the central Tibetan Plateau.ECOLOGICAL RESEARCH,36(3).
MLA	Xu-Ri,et al."The symbiotic nitrogen fixation by legumes in a legume-companion and a legume-dominant alpine steppe on the central Tibetan Plateau".ECOLOGICAL RESEARCH 36.3(2021).