干旱区生态环境知识资源中心(Arid): Irrigation alters source-composition characteristics of groundwater dissolved organic matter in a large arid river basin, Northwestern China

Arid

DOI	10.1016/j.scitotenv.2020.144372
	Irrigation alters source-composition characteristics of groundwater dissolved organic matter in a large arid river basin, Northwestern China
	Hu, Yue; Lu, YueHan; Edmonds, Jennifer; Liu, Chuankun; Zhang, Qiang; Zheng, Chunmiao
通讯作者	Lu, YH (corresponding author), Univ Alabama, Dept Geol Sci, Mol Ecogeochem Lab, Tuscaloosa, AL 35487 USA.
来源期刊	SCIENCE OF THE TOTAL ENVIRONMENT
ISSN	0048-9697
EISSN	1879-1026
出版年	2021
卷号	767
英文摘要	It has been well documented that agricultural activities lead to significant alterations in surface water dissolved organic matter (DOM), yet their impacts on groundwater DOM remain poorly constrained. The quantity, source, and composition of DOM play a pivotal role in a range of groundwater ecosystem services that are of important ecological and societal values. We assessed the impact of irrigation on the source and compositional characteristics of groundwater DOM in a large river basin supporting intensive agriculture in arid northwestern China. We sampled five water types along a river reach of approximately 40 km, including groundwater, river water, irrigation canal water, hyporheic water, and soil leachates. The excitation-emission matrix (EEM) measurements coupled with parallel factor analysis (PARAFAC) identified two terrestrial-derived, humic-like fluorescent components (C1 and C2) and one protein-like autochthonous component (C3). DOM composition and dissolved organic carbon (DOC) concentration varied as a function of water type, with subsurface waters showing relatively lower DOC and terrestrial humic fluorescence than surface waters. Combining nitrate, electrical conductivity, dissolved inorganic carbon (DIC), and delta C-13-DIC, irrigation-influenced samples were identified, and the influence of irrigation on groundwater DOM appeared only in shallow aquifers (<50 m). Irrigation-influenced groundwater exhibited higher DOC and terrestrial fluorescence than unimpacted groundwater, suggesting that irrigation return flows accelerated the downward movement of terrestrial humic compounds and led to their accumulation in aquifers. This effect was propagated via surface water-groundwater interactions to upwelling hyporheic water, which also showed enrichment in terrestrial fluorescence. Our findings demonstrate that irrigation can accelerate the biogeochemical cycling of organic compounds via a subsurface pathway of from the soil to aquifer to hyporheic zone. The enrichment of soil-derived compounds in subsurface waters may have important ecological consequences, such as altering the transport of nutrients and pollutants and changing carbon and energy flows across the surface-subsurface boundary. Published by Elsevier B.V.
英文关键词	Groundwater DOM Heihe River Basin Excitation-emission matrix Parallel factor analysis DOC Inigation return flows
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000617681100037
WOS类目	Environmental Sciences
WOS研究方向	Environmental Sciences & Ecology
来源机构	北京大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/368833
作者单位	[Hu, Yue; Liu, Chuankun; Zhang, Qiang] Chengdu Univ Technol, State Key Lab Geohazard Prevent & Geoenvironm Pro, Chengdu 610059, Peoples R China; [Lu, YueHan] Univ Alabama, Dept Geol Sci, Mol Ecogeochem Lab, Tuscaloosa, AL 35487 USA; [Edmonds, Jennifer] Nevada State Coll, Phys & Life Sci, Henderson, NV 89002 USA; [Zheng, Chunmiao] South Univ Sci & Technol China, Sch Environm Sci & Engn, Shenzhen, Peoples R China; [Zheng, Chunmiao] Peking Univ, Inst Water Sci, Beijing 100871, Peoples R China
推荐引用方式 GB/T 7714	Hu, Yue,Lu, YueHan,Edmonds, Jennifer,et al. Irrigation alters source-composition characteristics of groundwater dissolved organic matter in a large arid river basin, Northwestern China[J]. 北京大学,2021,767.
APA	Hu, Yue,Lu, YueHan,Edmonds, Jennifer,Liu, Chuankun,Zhang, Qiang,&Zheng, Chunmiao.(2021).Irrigation alters source-composition characteristics of groundwater dissolved organic matter in a large arid river basin, Northwestern China.SCIENCE OF THE TOTAL ENVIRONMENT,767.
MLA	Hu, Yue,et al."Irrigation alters source-composition characteristics of groundwater dissolved organic matter in a large arid river basin, Northwestern China".SCIENCE OF THE TOTAL ENVIRONMENT 767(2021).