Nitrate-nitrogen transport in streamwater and groundwater in a loess covered region: Sources, drivers, and spatiotemporal variation

doi:10.1016/j.scitotenv.2020.143278

	Nitrate-nitrogen transport in streamwater and groundwater in a loess covered region: Sources, drivers, and spatiotemporal variation
	Ji, Wangjia 2; Xiao, Jun 3; Toor, Gurpal S.1; Li, Zhi 2
刊名	SCIENCE OF THE TOTAL ENVIRONMENT
	2021-03-20
卷号	761 页码:12
关键词	Nitrate pollution Source identification Spatiotemporal variation The Loess Plateau
ISSN号	0048-9697
DOI	10.1016/j.scitotenv.2020.143278
通讯作者	Li, Zhi(lizhibox@nwafu.edu.cn)
英文摘要	Water quality is an increasing concern in the dry regions of the world as it affects and reduces the quantity of available water. Our objective was to investigate the sources, drivers, spatiotemporal patterns of nitrate-nitrogen (NO3-N) transport in the streamwater and groundwater in a dry and a wet season in seven large rivers located in the Loess Plateau of China (640,000 km(2), 100 million population), which is a region with marked influence of human activities on streamflow and groundwater. We collected 510 streamwater and groundwater samples and found that NO3-N was significantly lower in the dry season (< 5.0 mg L-1) than the wet season (> 5.0 mg L-1). In the wet season, NO3-N was lower in the streamwater than groundwater; however, the spatial variation in the NO3-N was greater in streamwater, with higher concentrations in two rivers (Wei and Fen). The source characterization using stable isotopes of NO3 from the Wei River showed that chemical N fertilizers and soil organic N contributed similar to 75% of NO3 to streamwater and that soil organic N was the greatest contributor of NO3 to groundwater (similar to 60%) than streamwater (< 40%). The spatial pattern of NO3-N was dominated by fertilizer application and varied seasonally with rainfall-runoff and streamflow-groundwater connectivity. Our results showed the complicated patterns and sources of NO3 pollution in streamwater and groundwater and highlight that more emphasis should be placed to prevent and restore the degraded water quality in the dry regions. (C) 2020 Elsevier B.V. All rights reserved.
资助项目	National Natural Science Foundation of China[42071043] ; Natural Science Foundation of Shaanxi Province
WOS关键词	LAND-USE CHANGE ; WATER-QUALITY ; RIVER-BASIN ; SOURCE APPORTIONMENT ; UNSATURATED ZONE ; SPATIAL-PATTERNS ; STABLE-ISOTOPES ; SOIL PROFILES ; YELLOW-RIVER ; HOT MOMENTS
WOS研究方向	Environmental Sciences & Ecology
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000607780900081
资助机构	National Natural Science Foundation of China ; Natural Science Foundation of Shaanxi Province
内容类型	期刊论文
源URL	[http://ir.ieecas.cn/handle/361006/15876]
专题	地球环境研究所_加速器质谱中心
通讯作者	Li, Zhi
作者单位	1.Univ Maryland, Dept Environm Sci & Technol, College Pk, MD 20742 USA 2.Northwest A&F Univ, Coll Nat Resources & Environm, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China 3.Chinese Acad Sci, Inst Earth Environm, Xian 710061, Shaanxi, Peoples R China
推荐引用方式 GB/T 7714	Ji, Wangjia,Xiao, Jun,Toor, Gurpal S.,et al. Nitrate-nitrogen transport in streamwater and groundwater in a loess covered region: Sources, drivers, and spatiotemporal variation[J]. SCIENCE OF THE TOTAL ENVIRONMENT,2021,761:12.
APA	Ji, Wangjia,Xiao, Jun,Toor, Gurpal S.,&Li, Zhi.(2021).Nitrate-nitrogen transport in streamwater and groundwater in a loess covered region: Sources, drivers, and spatiotemporal variation.SCIENCE OF THE TOTAL ENVIRONMENT,761,12.
MLA	Ji, Wangjia,et al."Nitrate-nitrogen transport in streamwater and groundwater in a loess covered region: Sources, drivers, and spatiotemporal variation".SCIENCE OF THE TOTAL ENVIRONMENT 761(2021):12.