干旱区生态环境知识资源中心(Arid): Hydroclimatic variability drives submarine groundwater discharge and nutrient fluxes in an anthropogenically disturbed, semi-arid estuary

Arid

DOI	10.1016/j.scitotenv.2020.142574
	Hydroclimatic variability drives submarine groundwater discharge and nutrient fluxes in an anthropogenically disturbed, semi-arid estuary
	Douglas, Audrey R.; Murgulet, Dorina; Montagna, Paul A.
通讯作者	Douglas, AR ; Murgulet, D (corresponding author), Texas A&M Univ, Ctr Water Supply Studies, Dept Phys & Environm Sci, 6300 Ocean Dr, Corpus Christi, TX 78412 USA.
来源期刊	SCIENCE OF THE TOTAL ENVIRONMENT
ISSN	0048-9697
EISSN	1879-1026
出版年	2021
卷号	755
英文摘要	Nutrient budgets in semi-arid estuaries, with ephemeral freshwater inflows and limited nutrient sources, are likely incomplete if contributions from submarine groundwater discharge (SGD) are not included. Here, the relative importance of saline/recirculated SGD-derived nutrient fluxes spatiotemporal variability to the overall nutrient budget is quantified for Nueces Bay, Texas, U.S.A., across hydroclimatic conditions ranging from drought to normal, to flood. On average, 67% of the variance in water quality is due to temporal differences while 16% is explained by spatial differences. Principal component analysis (PCA) reveals three principal components: freshwater inflow (PC1 28.8%), saline/recirculated SGD and recycled nitrogen (PC2 15.6%), and total SGD and new nitrogen (PC3 11.2%). Total SGD porewater fluxes ranged from 29.9-690.3 mmol.m(-2)d(-1) for ammonium, 0.21-18.7 mmol.m(-2)d(-1) for nitrite+nitrate, 3.1-51.3 mmol.m(-2)d(-1) for phosphate, 57.1-719.7 mmol.m(-2)d(-1) for silicate, and 95.9-36,838.5 mmol.m(-2)d(-1) for dissolved organic carbon. Total and saline/recirculated SGD fluxes were on average 150-26,000 and 5.8-466 times, respectively, greater than surface runoff fluxes across all seasons. Nitrogen (N) enrichment in porewater occurs near the agricultural fields because of soil N flushing and percolation to groundwater, which facilitates N-rich groundwater fluxes. There were substantial new N inputs from terrestrial groundwater following precipitation while saline/recirculated SGD of recycled N accounts for only <4% of total SGD inputs. The new N inputs occur in the river and river mouth during flooding, and near the north shore where topography and hydraulic gradients are steeper during drought. Thus, while significant inputs of N may be associated with atmospheric deposition, or remineralization in the porewater, groundwater is the highest contributor to the nutrient budget in Nueces Bay. This result implies that nutrient management strategies should focus on land-use practices to reduce N contamination of shallow groundwater and subsequent contamination of estuaries. (C) 2020 Elsevier B.V. All rights reserved.
英文关键词	Flood event Semi-arid estuary Nitrogen Submarine groundwater discharge (SGD) Nueces Bay Nitrogen budget
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000600786700030
WOS关键词	DISSIMILATORY NITRATE REDUCTION ; RADIUM ISOTOPES ; ORGANIC-MATTER ; AMMONIUM DNRA ; TOLO HARBOR ; HONG-KONG ; DAYA BAY ; NITROGEN ; WATER ; DENITRIFICATION
WOS类目	Environmental Sciences
WOS研究方向	Environmental Sciences & Ecology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/348162
作者单位	[Douglas, Audrey R.; Murgulet, Dorina] Texas A&M Univ, Ctr Water Supply Studies, Corpus Christi, TX 78412 USA; [Montagna, Paul A.] Texas A&M Univ, Harte Res Inst Gulf Mexico Studies, Corpus Christi, TX 78412 USA
推荐引用方式 GB/T 7714	Douglas, Audrey R.,Murgulet, Dorina,Montagna, Paul A.. Hydroclimatic variability drives submarine groundwater discharge and nutrient fluxes in an anthropogenically disturbed, semi-arid estuary[J],2021,755.
APA	Douglas, Audrey R.,Murgulet, Dorina,&Montagna, Paul A..(2021).Hydroclimatic variability drives submarine groundwater discharge and nutrient fluxes in an anthropogenically disturbed, semi-arid estuary.SCIENCE OF THE TOTAL ENVIRONMENT,755.
MLA	Douglas, Audrey R.,et al."Hydroclimatic variability drives submarine groundwater discharge and nutrient fluxes in an anthropogenically disturbed, semi-arid estuary".SCIENCE OF THE TOTAL ENVIRONMENT 755(2021).