Divergent composition and turnover of soil organic nitrogen along a climate gradient in arid and semiarid grasslands

doi:10.1016/j.geoderma.2018.04.020

CORC > 沈阳应用生态研究所 > 中国科学院沈阳应用生态研究所 > 沈阳应用生态研究所 > 期刊论文

	Divergent composition and turnover of soil organic nitrogen along a climate gradient in arid and semiarid grasslands
	Feng, Jiao 1,2; Turne, Benjamin L.3; Wei, Kai 1; Tian, Jihui 1; Chen, Zhenhua 1; Lu, Xiaotao 1; Wang, Chao 1; Chen, Lijun 1
刊名	GEODERMA
	2018-10-01
卷号	327 页码:36-44
关键词	Aridity Gradient Drylands Global Climate Change Organic Nitrogen Fractions Nitrogen-hydrolyzing Enzymes Nitrogen Cycling
ISSN号	0016-7061
DOI	10.1016/j.geoderma.2018.04.020
英文摘要	Greater aridity predicted with climate change in drylands worldwide will affect soil nitrogen (N) cycling and the associated ecosystem functions. Despite > 90% of soil N occurring in organic forms, the pathways of soil organic N (SON) turnover remain largely unknown in drylands, where biological activity is typically limited by water availability. Here we examined patterns of SON fractions and soil N-hydrolyzing enzyme activities across a 3700 km aridity gradient in arid and semiarid grasslands of northern China. We found that both the concentrations of all SON fractions and the proportion of more stable SON increased with increasing aridity index (AI, defined as mean annual precipitation/potential evapotranspiration). The largest SON fraction was hydrolysable NH4+ in arid sites, but amino acid-N in semiarid sites. The activities of enzymes that hydrolyze relatively stable SON polymers (protease, peptidase, and N-acetyl-beta-glucosaminidase) were negligible in arid sites (AI < 0.2), but increased significantly as Al increased in semiarid sites (AI > 0.2). Structural equation modeling indicated that the direct effect of microbial biomass on soil amidase was insignificant in arid sites, indicating that microbial SON turnover via enzymes is relatively weak. In semiarid sites, however, microbial biomass exerted significant direct positive effects on all soil N-hydrolyzing enzymes, suggesting strong microbial regulation of SON turnover via enzymatic mineralization. Altogether, our findings provide empirical evidence for divergent patterns of storage and turnover of SON between arid and semiarid grasslands.
WOS研究方向	Agriculture
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000435060200004
内容类型	期刊论文
源URL	[http://210.72.129.5/handle/321005/106591]
专题	沈阳应用生态研究所_沈阳应用生态研究所_期刊论文
通讯作者	Chen, Lijun
作者单位	1.Chinese Acad Sci, Inst Appl Ecol, POB 417, Shenyang 110016, Liaoning, Peoples R China 2.Chinese Acad Sci, Wuhan Bot Garden, Wuhan 430074, Hubei, Peoples R China 3.Smithsonian Trop Res Inst, Apartado 0843-03092, Balboa, Ancon, Panama
推荐引用方式 GB/T 7714	Feng, Jiao,Turne, Benjamin L.,Wei, Kai,et al. Divergent composition and turnover of soil organic nitrogen along a climate gradient in arid and semiarid grasslands[J]. GEODERMA,2018,327:36-44.
APA	Feng, Jiao.,Turne, Benjamin L..,Wei, Kai.,Tian, Jihui.,Chen, Zhenhua.,...&Chen, Lijun.(2018).Divergent composition and turnover of soil organic nitrogen along a climate gradient in arid and semiarid grasslands.GEODERMA,327,36-44.
MLA	Feng, Jiao,et al."Divergent composition and turnover of soil organic nitrogen along a climate gradient in arid and semiarid grasslands".GEODERMA 327(2018):36-44.