干旱区生态环境知识资源中心(Arid): Conversion from farmland to orchards has minor effects on nitrogen biological processes in deep loess deposits

Arid

DOI	10.1016/j.agee.2022.108111
	Conversion from farmland to orchards has minor effects on nitrogen biological processes in deep loess deposits
	Ji, Wangjia; Huang, Yanan; Qian, Xun; Bai, Edith; Smith, C. Ken; Li, Zhi
通讯作者	Li, Z
来源期刊	AGRICULTURE ECOSYSTEMS & ENVIRONMENT
ISSN	0167-8809
EISSN	1873-2305
出版年	2022
卷号	338
英文摘要	High nitrate (NO3--N) accumulation has been observed globally in vadose zones due to the overuse of synthetic fertilizer, but its impacts on nitrogen (N) biological processes remain poorly understood, especially after land use conversion from farmlands to deep-rooted apple orchards. In this study, we collected paired soil samples to determine available N contents, NO3--N isotopes, and abundances of N functional genes (NFGs) in 10-m loess profiles under cultivated farmlands and adjacent apple orchards (n = 300). The average NO3--N accumulation under orchards was 4773 kg N ha (1) (10 times higher than farmlands), with the NO3--N profiles resembling a parabolic curve within 0 -4 m below the surface. Regardless of excessive fertilizer application and welldeveloped root systems, the deep-rooted orchards had minor effects on N sources and biological processes in deep loess deposits, as indicated by our estimates of isotopes and NFGs abundances. We hypothesized that the limited and inactive microorganisms in the subsoil are more resistant to environmental disturbances, and that carbon source and ammonium substrate dominated the gene expression and occurrence of NFGs-indicated biological processes. The limited root biomass per unit depth and the inhibition effects of a dry soil horizon on root turnover and exudate release likely contributed to the less perturbed N biological processes under orchards. As the first study to explore N transformation processes in 10-m loess deposits, this study provided insights for complicated N biogeochemical cycles in arid regions with deep unsaturated soils and intensive agricultural land use.
英文关键词	Stable isotopes Nitrogen functional genes Microbial turnover potentials Loess Plateau Land use conversion
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000859261900008
WOS关键词	LAND-USE CHANGE ; MICROBIAL FUNCTIONAL GENES ; NITRATE ACCUMULATION ; CRITICAL ZONE ; FERTILIZER APPLICATION ; SOIL-PROFILE ; DENITRIFICATION ; GROUNDWATER ; RECHARGE ; IMPACTS
WOS类目	Agriculture, Multidisciplinary ; Ecology ; Environmental Sciences
WOS研究方向	Agriculture ; Environmental Sciences & Ecology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/391667
推荐引用方式 GB/T 7714	Ji, Wangjia,Huang, Yanan,Qian, Xun,et al. Conversion from farmland to orchards has minor effects on nitrogen biological processes in deep loess deposits[J],2022,338.
APA	Ji, Wangjia,Huang, Yanan,Qian, Xun,Bai, Edith,Smith, C. Ken,&Li, Zhi.(2022).Conversion from farmland to orchards has minor effects on nitrogen biological processes in deep loess deposits.AGRICULTURE ECOSYSTEMS & ENVIRONMENT,338.
MLA	Ji, Wangjia,et al."Conversion from farmland to orchards has minor effects on nitrogen biological processes in deep loess deposits".AGRICULTURE ECOSYSTEMS & ENVIRONMENT 338(2022).