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Zhang X, Li H, Wang X, Kuang X, Zhang Y, Xiao K, Xu C. A comprehensive analysis of submarine groundwater discharge and nutrient fluxes in the Bohai Sea, China. WATER RESEARCH 2024; 253:121320. [PMID: 38382290 DOI: 10.1016/j.watres.2024.121320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/02/2024] [Accepted: 02/14/2024] [Indexed: 02/23/2024]
Abstract
Groundwater discharge and associated nutrient fluxes in the Bohai Sea, China has attracted great attention, but most studies lacked high spatial resolution for the whole sea. As the largest semi-enclosed sea in China, the Bohai Sea is confronted with strong environmental pollution problems such as eutrophication induced by terrestrial nutrient inputs. However, the role of SGD has not been evaluated well for the whole Bohai Sea. In this study, stable isotopes (hydrogen and oxygen), radioactive isotope (228Ra), salinity, and temperature were combined to trace the diluted seawater. Mass balances of 228Ra, oxygen isotope, and salinity were used to quantify SGD and nutrient fluxes to the Bohai Sea. The estimated submarine fresh groundwater discharge (SFGD) and SGD to the Bohai Sea were (6.0 ± 0.5) × 109 and (2.7 ± 1.6) × 1011 m3 a-1, respectively. SFGD represents 10 % to 11 % of the total river discharge and SGD is about 2 to 8 folds of the total river discharge to the sea. Moreover, SGD derived dissolved nutrients to the Bohai Sea were (4.8 ± 4.0) × 1010 mol a-1 for dissolved inorganic nitrogen, (1.9 ± 1.7) × 1010 mol a-1 for dissolved inorganic phosphorus, and (6.7 ± 5.5) × 1010 mol a-1 for silicon. These nutrient inputs were about 10 to 20 folds of the total riverine inputs. Overall, this study underscores the importance of evaluating SGD to better understand the terrestrial imported nutrients in regional scale.
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Affiliation(s)
- Xiaolang Zhang
- Department of Geosciences, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Hailong Li
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Xuejing Wang
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Xingxing Kuang
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yan Zhang
- State Key Laboratory of Biogeology and Environmental Geology and School of Water Resources and Environment, China University of Geosciences-Beijing, Beijing 100083, China
| | - Kai Xiao
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Chao Xu
- Department of Geosciences, Texas Tech University, Texas 79409, USA
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Nakajima T, Kuragano M, Yamada M, Sugimoto R. Comparing nearshore and embayment scale assessments of submarine groundwater discharge: Significance of offshore groundwater discharge as a nutrient pathway. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168068. [PMID: 37914127 DOI: 10.1016/j.scitotenv.2023.168068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/07/2023] [Accepted: 10/21/2023] [Indexed: 11/03/2023]
Abstract
Submarine groundwater discharge (SGD) can influence biogeochemical cycles in coastal seas by delivering nutrients from the seafloor. Comparison between the nearshore and embayment scale assessments of SGD against river water discharge would be crucial for understanding biogeochemical impacts on the coastal seas because the discharge pattern (non-point or point pathway) is different. Here, we quantified SGD contribution to rivers in nutrient budgets at two scales within a coastal embayment (Obama Bay, Japan) by mass balance models of radon and radium isotopes. We then compared the SGD contribution between the two scales by the meta-analysis for regional data sets conducted in nearshore and embayment scales. The estimated SGD rates in the nearshore and embayment scales in the bay were 7.8 cm d-1 and 20.0 cm d-1, indicating that offshore SGD was more significant than nearshore. The ratios of nutrient fluxes derived from SGD to rivers (SGD:River) in the nearshore scale were 1.7 for dissolved inorganic nitrogen (DIN), 3.0 for phosphorus (DIP), and 0.5 for silica (DSi), while those in the embayment scale increased to 10.4 for DIN, 18.5 for DIP, and 3.9 for DSi. This result indicates that SGD-derived nutrients become more important at larger spatial scales. Meta-analysis revealed that the difference in the contribution of SGD to rivers was affected by the seafloor size and there was no significant difference in SGD rates between nearshore and embayment scale studies. However, our regional study shows the site-specific pattern that SGD rates in the embayment scale were higher than those in the nearshore scale. Overall, we clarified that SGD can be a crucial nutrient pathway for coastal embayments regardless of the spatial scales and contribute to coastal nutrient biogeochemistry in more offshore areas.
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Affiliation(s)
- Toshimi Nakajima
- Graduate School of Bioscience and Biotechnology, Fukui Prefectural University, Fukui, Japan.
| | - Mao Kuragano
- Graduate School of Bioscience and Biotechnology, Fukui Prefectural University, Fukui, Japan.
| | - Makoto Yamada
- Faculty of Economics, Ryukoku University, Kyoto, Japan.
| | - Ryo Sugimoto
- Faculty of Marine Biosciences and Technology, Fukui Prefectural University, Fukui, Japan.
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Xue Y, Zhang Y, Zhang M, Wang X, Xiao K, Luo M, Li H. Submarine groundwater discharge and associated metal elements into an urbanized bay. MARINE POLLUTION BULLETIN 2023; 192:115092. [PMID: 37285609 DOI: 10.1016/j.marpolbul.2023.115092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 04/22/2023] [Accepted: 05/19/2023] [Indexed: 06/09/2023]
Abstract
In this study, geochemical tracers (radium isotopes) and heavy metals (Pb, Zn, Cd, Cr and As) were analyzed to derive the submarine groundwater discharge (SGD) and associated metal fluxes during four seasons in an urbanized bay (Daya Bay, China). Results showed that Pb and Zn were the main pollutants in bay water. SGD was found to exhibit an obvious seasonal trend (autumn > summer > spring > winter). Such seasonal patterns may be related to the hydraulic gradient between groundwater level and sea level, storm surges and tidal range. SGD was a dominant source of marine metal elements, contributing 19 %-51 % of the total inputs of metals into Daya Bay. The bay water was classified as slight pollution to heavy pollution, which could be linked to SGD-derived metal fluxes. This study provides a better understanding of the important role that SGD plays in metal budgets and ecological environments of coastal waters.
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Affiliation(s)
- Yan Xue
- MOE Key Laboratory of Groundwater Circulation & Environment Evolution and School of Water Resources and Environment, China University of Geosciences-Beijing, Beijing 100083, China
| | - Yan Zhang
- MOE Key Laboratory of Groundwater Circulation & Environment Evolution and School of Water Resources and Environment, China University of Geosciences-Beijing, Beijing 100083, China.
| | - Meng Zhang
- Beijing Boyuan Huanqing Technology Co., Ltd, 100053, China
| | - Xuejing Wang
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Kai Xiao
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Manhua Luo
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Hailong Li
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
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Anthropogenic interventions on land neutrality in a critically vulnerable estuarine island ecosystem: a case of Munro Island (India). Sci Rep 2023; 13:1458. [PMID: 36702916 PMCID: PMC9879962 DOI: 10.1038/s41598-023-28695-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 01/20/2023] [Indexed: 01/27/2023] Open
Abstract
All landscapes, including estuarine islands, normally try to restore their geomorphic isostasy in all anthropogenic interventions on land dynamics. Munroe Island has been experiencing drastic environmental degradation, such as land subsidence, severe tidal/monsoon flooding, subsidence of build-ups and a drastic decay in agricultural productivity. This paper examines the role of anthropo-geomorphic interventions causing for the land degradation in Munroe Island through a multidisciplinary approach. Multidated, multiresolution satellite products and published maps, spanning a period of about six decades from 1960 to 2021, were used to understand the different geomorphic and geographical processes in the study area. Evaluation of the temporal bathymetric datasets, salinity measurements of the river and estuary, borehole data logs of the area and electrical resistivity surveys of the island were analyzed to find out the causative factors for the disturbances in the land neutrality, along with the tidal hydrodynamic changes in the region. The study shows about 14% of the total land area was vanished during the study period, and more than 25% of the area is under stress, leading to further land degradation. More than 500 households are forced to vacate their residence due to land subsidence/flooding. Lack of required freshwater and sediment supply from the Kallada river after the construction of the Thenmala reservoir in the Kallada river as well as the uncontrolled sand mining prevailed are the key factors for the environmental degradation of Munroe Island. The paper describes the role and colinkages of human-induced hydrogeomorphic interventions on a geomorphic system, in charge of the environmental degradation and land subsidence crisis of an estuarine island ecosystem and discusses the concerns related to the management strategies of such region.
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Sekar S, Perumal M, Roy PD, Ganapathy M, Senapathi V, Yong Chung S, Elzain HE, Duraisamy M, Kamaraj J. A review on global status of fresh and saline groundwater discharge into the ocean. ENVIRONMENTAL MONITORING AND ASSESSMENT 2022; 194:915. [PMID: 36255565 DOI: 10.1007/s10661-022-10566-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 02/25/2022] [Indexed: 06/16/2023]
Abstract
Submarine groundwater discharge (SGD) is the groundwater flow from land to the sea across the seabed, and it includes both terrane freshwater and recirculated seawater in the sub-surface. This review (i) systematically evaluates findings of various quantification methodologies, (ii) examines the estimated SGD in scientific publications between 2000 and 2020, and (iii) quantitatively evaluates current situation of coastal zone management through the bibliometric analysis of research papers. Apart from enhancing the shortage of groundwater resources in coastal area, the SGD brings nutrients (nitrate and phosphate), toxic heavy metals, and organic compounds, and thus contaminate the seawater. Therefore, the improved understanding about location and quantity of global SGD is essential to conserve the coastal and ocean ecosystems.
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Affiliation(s)
- Selvam Sekar
- Department of Geology, V.O. Chidambaram College, Tuticorin, Tamil Nadu, India.
| | - Muthukumar Perumal
- Department of Geology, V.O. Chidambaram College, Tuticorin, Tamil Nadu, India
- Registration No: 19212232221045, Affiliated to Manonmaniam Sundranar University, Tirunelveli, Tamil Nadu, India
| | - Priyadarsi Debajyoti Roy
- Instituto de Geología, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, CP, Mexico City, 04510, Mexico
| | - Moorthy Ganapathy
- Department of Geology, V.O. Chidambaram College, Tuticorin, Tamil Nadu, India
| | | | - Sang Yong Chung
- Department of Earth & Environmental Sciences, Institute of Environmental Geosciences, Pukyong National University, Busan, 608-737, Korea
| | - Hussam Eldin Elzain
- Water Research Center, Sultan Qaboos University, Muscat, Oman, United Arab Emirates
| | - Manimaran Duraisamy
- Department of Geology, V.O. Chidambaram College, Tuticorin, Tamil Nadu, India
| | - Jesuraja Kamaraj
- Department of Geology, V.O. Chidambaram College, Tuticorin, Tamil Nadu, India
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Murgulet D, Lopez CV, Douglas AR. Radioactive and stable isotopes reveal variations in nearshore submarine groundwater discharge composition and magnitude across low inflow northwestern Gulf of Mexico estuaries. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 823:153814. [PMID: 35157869 DOI: 10.1016/j.scitotenv.2022.153814] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 02/01/2022] [Accepted: 02/07/2022] [Indexed: 06/14/2023]
Abstract
To determine how submarine groundwater discharge (SGD) magnitudes and composition (fresh or saline/recirculated) vary in nearshore low inflow estuaries across ⁓125 km of a semiarid coastline, this study assessed three south Texas estuaries, using radon [222Rn], radium [226Ra and 224Ra], and water isotopes [δ18O and δD]. Mass balance models of time-series 222Rn, found to be representative of total SGD in this study, revealed much higher SGD inputs to the Nueces Estuary (average [x̅] Nueces, Corpus Christi and Oso Bays: 120, 83, and 44 cm·d-1, respectively), attributed to anthropogenically-disturbed substrates and potentially surfacing growth-faults. The lowest 222Rn-derived SGD occurred in the Upper Laguna Madre Estuary (x̅: Upper Laguna Madre and Baffin Bay: 21 and 18 cm·d-1, respectively), explained by the drier climate, lower anthropogenic disturbance, and neighboring groundwater cone of depression. Aransas Bay in the Mission Aransas Estuary received greater average annual precipitation but exhibited low total SGD rates (x̅: 23 cm·d-1). Seasonally, average 222Rn-derived SGD rates increased following Hurricane Harvey (43 cm·d-1 in spring to 64 cm·d-1 in summer). In the Nueces Estuary, the overall 222Rn-derived SGDs were substantially higher than SGDs from 224Ra and 226Ra. The closer agreement between 224Ra and 222Rn-derived SGD and larger 224Ra rates in the Upper Laguna Madre Estuary, Aransas Bay and Oso Bay indicate that saline/recirculated SGD contributions were significant. Values of δ18O and δD confirm these types of inputs, with effects of evaporation/salinization more pronounced where recirculation was predominant and the opposite where terrestrial/222Rn-derived SGD inputs dominate. 226Ra-derived SGDs were lower than the 224Ra due to different behavior of the two isotopes while released into water following transport through saline and fine-grained estuarine sediments or due to wind-driven disturbances.
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Affiliation(s)
- Dorina Murgulet
- Texas A&M University-Corpus Christi, Corpus Christi, TX 78412, USA.
| | - Cody V Lopez
- Texas A&M University-Corpus Christi, Corpus Christi, TX 78412, USA
| | - Audrey R Douglas
- Harte Research Institute for Gulf of Mexico Studies, Texas A&M University-Corpus Christi, Corpus Christi, TX 78412, USA
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Peng T, Zhu Z, Du J, Liu J. Effects of nutrient-rich submarine groundwater discharge on marine aquaculture: A case in Lianjiang, East China Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 786:147388. [PMID: 33984696 DOI: 10.1016/j.scitotenv.2021.147388] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 04/08/2021] [Accepted: 04/23/2021] [Indexed: 06/12/2023]
Abstract
Submarine groundwater discharge (SGD) and associated nutrient have long been received insufficient attention in the aquaculture areas of Lianjiang, East China Sea. In this study, we used 224Ra mass balance model to evaluate the importance of SGD in the aquaculture areas of Lianjiang in different seasons. The results showed that SGD fluxes were 0.14 ± 0.070 m3 m-2 d-1 in July and 0.077 ± 0.040 m3 m-2 d-1 in October 2019, which corresponded to approximately 22% and 32% of the river discharge, respectively. Nevertheless, the dissolved inorganic nitrogen (DIN) and phosphorus (DIP) fluxes contributed by SGD over total nutrient inputs were approximately 58% and 73%, respectively in July, 11% and 33%, respectively in October 2019. The ratio of DIN to DIP in seawater was slightly higher than that derived from SGD in July and significantly lower than that derived from the river and SGD in October, which was prone to profound modulated by shellfish (e.g., clam Ruditapes philippinarum and Sinonovacula constricta) and nori (e.g., Pyropia haitanensis) that selectively acquire nitrogen and phosphorous, suggesting that SGD could affect the nutrient structure and aquaculture activities in Lianjiang. Moreover, the new primary production via SGD yielded (2.47 ± 1.32) × 103 mg C m-2 d-1 in July and (3.52 ± 1.76) × 102 mg C m-2 d-1 in October 2019, which were approximately 8-25% and 10-31% of the production in the entire study area. These meaningful discoveries indicated that SGD and associated nutrient are the predominant regulator of nutrient and aquaculture structure under significant seasonal differences.
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Affiliation(s)
- Tong Peng
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China
| | - Zhuoyi Zhu
- School of Oceanography, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Jinzhou Du
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China
| | - Jianan Liu
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China.
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Das K, Mishra AK, Singh A, Agrahari S, Chakrabarti R, Mukherjee A. Solute exchanges between multi-depth groundwater and surface water of climatically vulnerable Gangetic delta front aquifers of Sundarbans. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 284:112026. [PMID: 33540200 DOI: 10.1016/j.jenvman.2021.112026] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 01/15/2021] [Accepted: 01/16/2021] [Indexed: 06/12/2023]
Abstract
The coastal aquifers of Sundarbans, an UNESCO world biodiversity heritage site, are highly vulnerable due to changing climatic conditions, intensification and increasing frequency of extreme climate events and uncontrolled abstraction of groundwater. The exchange of solutes between hydraulically connective shallow and deep aquifers, the seawater intrusion and the role of growing population are poorly understood in the Sundarbans. This study aims to address the solute exchange (Cl-, Sr2+, and salinity) process between surface water and groundwater (SW-GW) at local to regional scale under variable hydraulic head conditions, where annual rainfall is declining and population density is increasing [population 573 (1991) to 819 (2011)/Km2]. Electrical resistivity tomography (ERT) in combination with salinity and δ18O data was used to address the exchange of solutes between SW-GW in a hydraulic continuation. The results revealed that regionally, the Cl- concentration of Sundarbans shows an increasing trend (average 329-351 mg/L) with declining groundwater levels (⁓3 m). Local, depth-dependent study depicting there is a predominant exchange of Sr2+ between shallow depth [D1: 14-25 and D2: 30-50 m below ground level (m bgl)] with seawater (Sr2+: 30-85 μM), which is possibly absent at greater depths (D3:115 and D4: 333 m bgl). The recorded Sr2+ content ranged from 25 to 102 and 16 to 78 μM for shallow depth D1 and D2, respectively, whereas, the Sr2+ concentrations ranged from 1.4 to 6.8 and 1.2 to 5.7 μM for D3 and D4, respectively. The ERT data showed progressively increasing resistivity with increasing depth, similar to high salinity and enriched δ18O at shallow depths and depleted δ18O with low salinity at higher depth reflects the continuous distribution of solutes, which is possibly a result of local downward migration of contaminated shallow brackish water within this physically disconnected zone. The lateral and vertical transportation of solutes in variable hydraulic head conditions would be a measure of drinking water threat in present-day and in imminent future for millions of inhabitants near the coastal area.
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Affiliation(s)
- Kousik Das
- School of Environmental Science and Engineering, Indian Institute of Technology Kharagpur, West Bengal, India
| | - Anith Kumar Mishra
- Department of Geology and Geophysics, Indian Institute of Technology Kharagpur, West Bengal, India
| | - Akarsh Singh
- Department of Geology and Geophysics, Indian Institute of Technology Kharagpur, West Bengal, India
| | - Sudha Agrahari
- Department of Geology and Geophysics, Indian Institute of Technology Kharagpur, West Bengal, India
| | - Ramananda Chakrabarti
- Centre for Earth Sciences, Indian Institute of Science, Bangalore, 560012, India; Interdisciplinary Centre for Water Research, Indian Institute of Science, Bangalore, 560012, India
| | - Abhijit Mukherjee
- School of Environmental Science and Engineering, Indian Institute of Technology Kharagpur, West Bengal, India; Department of Geology and Geophysics, Indian Institute of Technology Kharagpur, West Bengal, India; Applied Policy Advisory to Hydrogeosciences Group, Indian Institute of Technology Kharagpur, West Bengal, India.
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9
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Cheng KH, Luo X, Jiao JJ. Two-decade variations of fresh submarine groundwater discharge to Tolo Harbour and their ecological significance by coupled remote sensing and radon-222 model. WATER RESEARCH 2020; 178:115866. [PMID: 32380295 DOI: 10.1016/j.watres.2020.115866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 04/20/2020] [Accepted: 04/22/2020] [Indexed: 06/11/2023]
Abstract
Although submarine groundwater discharge (SGD) comprises an insignificant proportion of the global hydrologic cycle, it contributes significantly to chemical fluxes into the coastal waters due to concentrated constituents in coastal groundwater. Large nutrient loadings derived from SGD can lead to a series of environmental and ecological problems such as algal blooms, resulting in water discoloration, severe dissolved oxygen depletion, and eventually beach closures and massive fish kills. Previous studies have demonstrated the relationship between algal blooms and SGD obtained from direct measurement with seepage meters or from geo-tracer (i.e., radon and radium) based models; these traditional methods are time-consuming, laborious and point monitoring, and can hardly achieve a high spatiotemporal resolution SGD estimation, which is vital in revealing the effects of SGD to algal blooms over a long period. Alternatively, remote sensing methods for high spatiotemporal resolution SGD localization and quantification are applicable and effective. The temperature difference or anomaly between groundwater and coastal water extracted from satellite thermal images can be used as the indicator to localize and detect SGD especially its fresh component (or fresh SGD). In this study, multi-year (2005, 2011 and 2018) radon samples in Tolo Harbour were used to train regression models between in-situ radon (Rn) activity and the temperature anomaly by Landsat satellite thermal images. The models were used to estimate two-decade variations of fresh SGD in Tolo Harbour. The synergistic analysis between the time series of fresh SGD derived from regression models and high spatiotemporal resolution ecological metrics (chlorophyll-a, algal cell counts, and E.coli) leads to the findings that the increase of the fresh SGD associated with high nutrient concentrations is witnessed 10-20 days before the observations of algal bloom events. This study makes the first attempt to demonstrate the strong relation between the SGD and algal blooms over a vicennial span, and also provides a cost effective and robust technique to estimate SGD on a bay scale.
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Affiliation(s)
- K H Cheng
- Department of Earth Science, The University of Hong Kong, Hong Kong, China
| | - Xin Luo
- Department of Earth Science, The University of Hong Kong, Hong Kong, China
| | - Jiu Jimmy Jiao
- Department of Earth Science, The University of Hong Kong, Hong Kong, China.
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10
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Reply to the Letter-to-the-Editor of Dr. Noble Jacob regarding article “Radon isotope assessment of Submarine Groundwater Discharge (SGD) in Coleroon River Estuary, Tamil Nadu, India”, DOI: https://doi.org/10.1007/s10967-018-5877-2. J Radioanal Nucl Chem 2018. [DOI: 10.1007/s10967-018-5998-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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11
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Painter SC, Lapworth DJ, Woodward EMS, Kroeger S, Evans CD, Mayor DJ, Sanders RJ. Terrestrial dissolved organic matter distribution in the North Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 630:630-647. [PMID: 29494972 DOI: 10.1016/j.scitotenv.2018.02.237] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/19/2018] [Accepted: 02/19/2018] [Indexed: 06/08/2023]
Abstract
The flow of terrestrial carbon to rivers and inland waters is a major term in the global carbon cycle. The organic fraction of this flux may be buried, remineralized or ultimately stored in the deep ocean. The latter can only occur if terrestrial organic carbon can pass through the coastal and estuarine filter, a process of unknown efficiency. Here, data are presented on the spatial distribution of terrestrial fluorescent and chromophoric dissolved organic matter (FDOM and CDOM, respectively) throughout the North Sea, which receives organic matter from multiple distinct sources. We use FDOM and CDOM as proxies for terrestrial dissolved organic matter (tDOM) to test the hypothesis that tDOM is quantitatively transferred through the North Sea to the open North Atlantic Ocean. Excitation emission matrix fluorescence and parallel factor analysis (EEM-PARAFAC) revealed a single terrestrial humic-like class of compounds whose distribution was restricted to the coastal margins and, via an inverse salinity relationship, to major riverine inputs. Two distinct sources of fluorescent humic-like material were observed associated with the combined outflows of the Rhine, Weser and Elbe rivers in the south-eastern North Sea and the Baltic Sea outflow to the eastern central North Sea. The flux of tDOM from the North Sea to the Atlantic Ocean appears insignificant, although tDOM export may occur through Norwegian coastal waters unsampled in our study. Our analysis suggests that the bulk of tDOM exported from the Northwest European and Scandinavian landmasses is buried or remineralized internally, with potential losses to the atmosphere. This interpretation implies that the residence time in estuarine and coastal systems exerts an important control over the fate of tDOM and needs to be considered when evaluating the role of terrestrial carbon losses in the global carbon cycle.
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Affiliation(s)
| | | | | | - Silke Kroeger
- Centre for Environment, Fisheries and Aquaculture Science, Lowestoft, UK
| | - Chris D Evans
- Centre for Ecology and Hydrology, Environment Centre Wales, Bangor, UK
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12
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Cho HM, Kim G, Kwon EY, Moosdorf N, Garcia-Orellana J, Santos IR. Radium tracing nutrient inputs through submarine groundwater discharge in the global ocean. Sci Rep 2018; 8:2439. [PMID: 29403050 PMCID: PMC5799265 DOI: 10.1038/s41598-018-20806-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 01/24/2018] [Indexed: 11/25/2022] Open
Abstract
Riverine and atmospheric inputs are often considered as the main terrestrial sources of dissolved inorganic nitrogen (DIN), phosphorus (DIP), and silicon (DSi) in the ocean. However, the fluxes of nutrients via submarine groundwater discharge (SGD) often exceed riverine inputs in different local and regional scale settings. In this study, we provide a first approximation of global nutrient fluxes to the ocean via total SGD, including pore water fluxes, by combining a global compilation of nutrient concentrations in groundwater and the SGD-derived 228Ra fluxes. In order to avoid overestimations in calculating SGD-derived nutrient fluxes, the endmember value of nutrients in global groundwater was chosen from saline groundwater samples (salinity >10) which showed relatively lower values over all regions. The results show that the total SGD-derived fluxes of DIN, DIP, and DSi could be approximately 1.4-, 1.6-, and 0.7-fold of the river fluxes to the global ocean (Indo-Pacific and Atlantic Oceans), respectively. Although significant portions of these SGD-derived nutrient fluxes are thought to be recycled within sediment-aquifer systems over various timescales, SGD-derived nutrient fluxes should be included in the global ocean budget in order to better understand dynamic interactions at the land-ocean interface.
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Affiliation(s)
- Hyung-Mi Cho
- School of Earth and Environmental Sciences/RIO, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea
| | - Guebuem Kim
- School of Earth and Environmental Sciences/RIO, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea.
| | - Eun Young Kwon
- IBS Center for Climate Physics, Pusan National University, 2 Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 46241, Korea
| | - Nils Moosdorf
- Leibniz Center for Tropical Marine Ecology, Fahrenheitsrasse 6, 28359, Bremen, Germany
| | - Jordi Garcia-Orellana
- Department de Física - Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Catalonia, Spain
| | - Isaac R Santos
- National Marine Science Centre, Southern Cross University, PO Box 4321, Coffs Harbour, 2450 NSW, Australia
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13
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Atoll Groundwater Movement and Its Response to Climatic and Sea-Level Fluctuations. WATER 2017. [DOI: 10.3390/w9090650] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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14
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Luo X, Jiao JJ. Submarine groundwater discharge and nutrient loadings in Tolo Harbor, Hong Kong using multiple geotracer-based models, and their implications of red tide outbreaks. WATER RESEARCH 2016; 102:11-31. [PMID: 27318300 DOI: 10.1016/j.watres.2016.06.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 05/31/2016] [Accepted: 06/06/2016] [Indexed: 06/06/2023]
Abstract
Multiple tracers, including radium quartet, (222)Rn and silica are used to quantify submarine groundwater discharge (SGD) into Tolo Harbor, Hong Kong in 2005 and 2011. Five geotracer models based on the end member model of (228)Ra and salinity and mass balance models of (226)Ra, (228)Ra, (222)Rn, and silica were established and all the models lead to an estimate of the SGD rate of the same order of magnitude. In 2005 and 2011, respectively, the averaged SGD based on these models is estimated to be ≈ 5.42 cm d(-1) and ≈2.66 cm d(-1), the SGD derived DIN loadings to be 3.5 × 10(5) mol d(-1) and 1.5 × 10(5) mol d(-1), and DIP loadings to be 6.2 × 10(3) mol d(-1) and 1.1 × 10(3) mol d(-1). Groundwater borne nutrients are 1-2 orders of magnitude larger than other nutrient sources and the interannual variation of nutrient concentration in the embayment is more influenced by the SGD derived loadings. Annual DIP concentrations in the harbor water is positively correlated with the precipitation and annual mean tidal range, and negatively correlated with evapotranspiration from 2000 to 2013. Climatologically driven SGD variability alters the SGD derived DIP loadings in this phosphate limited environment and may be the causative factor of interannual variability of red tide outbreaks from 2000 to 2013. Finally, a conceptual model is proposed to characterize the response of red tide outbreaks to climatological factors linked by SGD. The findings from this study shed light on the prediction of red tide outbreaks and coastal management of Tolo Harbor and similar coastal embayments elsewhere.
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Affiliation(s)
- Xin Luo
- Department of Earth Sciences, The University of Hong Kong, PR China; The University of Hong Kong, Shenzhen Research Institute (SRI), Shenzhen, PR China
| | - Jiu Jimmy Jiao
- Department of Earth Sciences, The University of Hong Kong, PR China; The University of Hong Kong, Shenzhen Research Institute (SRI), Shenzhen, PR China.
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15
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Szymczycha B, Kroeger KD, Pempkowiak J. Significance of groundwater discharge along the coast of Poland as a source of dissolved metals to the southern Baltic Sea. MARINE POLLUTION BULLETIN 2016; 109:151-162. [PMID: 27293076 DOI: 10.1016/j.marpolbul.2016.06.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 05/25/2016] [Accepted: 06/02/2016] [Indexed: 06/06/2023]
Abstract
Fluxes of dissolved trace metals (Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn) via groundwater discharge along the southern Baltic Sea have been assessed for the first time. Dissolved metal concentrations in groundwater samples were less variable than in seawater and were generally one or two orders of magnitude higher: Cd (2.1-2.8nmolL(-1)), Co (8.70-8.76nmolL(-1)), Cr (18.1-18.5nmolL(-1)), Mn (2.4-2.8μmolL(-1)), Pb (1.2-1.5nmolL(-1)), Zn (33.1-34.0nmolL(-1)). Concentrations of Cu (0.5-0.8nmolL(-1)) and Ni (4.9-5.8nmolL(-1)) were, respectively, 32 and 4 times lower, than in seawater. Groundwater-derived trace metal fluxes constitute 93% for Cd, 80% for Co, 91% for Cr, 6% for Cu, 66% for Mn, 4% for Ni, 70% for Pb and 93% for Zn of the total freshwater trace metal flux to the Bay of Puck. Groundwater-seawater mixing, redox conditions and Mn-cycling are the main processes responsible for trace metal distribution in groundwater discharge sites.
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Affiliation(s)
- Beata Szymczycha
- Institute of Oceanology, Polish Academy of Sciences, Powstańców Warszawy 55, 81-712 Sopot, Poland; USGS Coastal and Marine Science Center, 384 Woods Hole Road,10, Woods Hole, MA 02543, USA
| | - Kevin D Kroeger
- USGS Coastal and Marine Science Center, 384 Woods Hole Road,10, Woods Hole, MA 02543, USA
| | - Janusz Pempkowiak
- Institute of Oceanology, Polish Academy of Sciences, Powstańców Warszawy 55, 81-712 Sopot, Poland
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16
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Dimova NT, Paytan A, Kessler JD, Sparrow KJ, Garcia-Tigreros Kodovska F, Lecher AL, Murray J, Tulaczyk SM. Current Magnitude and Mechanisms of Groundwater Discharge in the Arctic: Case Study from Alaska. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:12036-12043. [PMID: 26372173 DOI: 10.1021/acs.est.5b02215] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
To better understand groundwater-surface water dynamics in high latitude areas, we conducted a field study at three sites in Alaska with varying permafrost coverage. The natural groundwater tracer ((222)Rn, radon) was used to evaluate groundwater discharge, and electrical resistivity tomography (ERT) was used to examine subsurface mixing dynamics. Different controls govern groundwater discharge at these sites. In areas with sporadic permafrost (Kasitsna Bay), the major driver of submarine groundwater discharge is tidal pumping, due to the large tidal oscillations, whereas at Point Barrow, a site with continuous permafrost and small tidal amplitudes, fluxes are mostly affected by seasonal permafrost thawing. Extended areas of low resistivity in the subsurface alongshore combined with high radon in surface water suggests that groundwater-surface water interactions might enhance heat transport into deeper permafrost layers promoting permafrost thawing, thereby enhancing groundwater discharge.
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Affiliation(s)
- Natasha T Dimova
- Department of Geological Sciences, University of Alabama , Tuscaloosa, Alabama 35487, United States
| | | | - John D Kessler
- Department of Earth and Environmental Sciences, University of Rochester , Rochester, New York 14627, United States
| | - Katy J Sparrow
- Department of Earth and Environmental Sciences, University of Rochester , Rochester, New York 14627, United States
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17
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Rapaglia J, Grant C, Bokuniewicz H, Pick T, Scholten J. A GIS typology to locate sites of submarine groundwater discharge. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2015; 145:10-18. [PMID: 25863321 DOI: 10.1016/j.jenvrad.2015.03.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 03/11/2015] [Accepted: 03/11/2015] [Indexed: 06/04/2023]
Abstract
Although many researchers agree on the importance of submarine groundwater discharge (SGD), it remains difficult to locate and quantify this process. A groundwater typology was developed based on local digital elevation models and compared to concurrent radon mapping indicative of SGD in the Niantic River, CT USA. Areas of high radon activity were located near areas of high flow accumulation lending evidence to the utility of this approach to locate SGD. The benefits of this approach are three-fold: fresh terrestrial SGD may be quickly located through widely-available digital elevation models at little or no cost to the investigator; fresh SGD may also be quantified through the GIS approach by multiplying pixelated flow accumulation with the expected annual recharge; and, as these data necessarily quantify only fresh SGD, a comparison of these data with SGD as calculated by Rn activity may allow for the separation of the fresh and circulated fractions of SGD. This exercise was completed for the Niantic River where SGD as calculated by the GIS model is 1.2 m(3)/s, SGD as calculated by Rn activity is 0.73-5.5 m(3)/s, and SGD as calculated via a theoretical approach is 1.8-4.3 m(3)/s. Therefore fresh, terrestrial SGD accounts for 22-100% of total SGD in the Niantic River.
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Affiliation(s)
- John Rapaglia
- Department of Biology, Sacred Heart University, 5151 Park Avenue, Fairfield, CT 06825, USA.
| | - Carley Grant
- Department of Biology, Sacred Heart University, 5151 Park Avenue, Fairfield, CT 06825, USA.
| | - Henry Bokuniewicz
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794, USA.
| | - Tsvi Pick
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794, USA.
| | - Jan Scholten
- Institute of Geosciences, Christian Albrechts University of Kiel, Otto-Hahn Platz 1, 24098 Kiel, Germany.
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18
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Goodridge BM, Melack JM. Temporal evolution and variability of dissolved inorganic nitrogen in beach pore water revealed using radon residence times. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:14211-14218. [PMID: 25399780 DOI: 10.1021/es504017j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We coupled measurements of beach pore water residence time, determined using the radioisotopic tracer (222)Rn, with dissolved carbon and nitrogen chemistry to identify the temporal evolution and variability of dissolved inorganic nitrogen (DIN) concentrations in beach pore water along the Santa Barbara, California coastline. Pore water dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) ratios (DOC:TDN) were negative exponentially correlated with residence time. Mean pore water residence times were positively correlated with tidal amplitudes, and ranged from 4.4 to 6.4 days. We used this range in mean residence times to model radon residence time distributions (RTDs), and integrated them with modeled DIN vs residence time relationships (DIN-temporal evolution, or DIN-te curves) to derive volume-weighted mean (VWM) DIN concentrations. We observed 1.2-fold and 5.2-fold differences (20% and 420% increases) in VWM DIN concentrations over the range in modeled RTDs and DIN-te curves, respectively, and a maximum 6.4-fold difference (540% increase) in VWM DIN concentrations for an interactive shift in the RTD and the DIN-te curve. Our study suggests that accounting for temporal variability in the RTD and DIN concentration of pore water is necessary to obtain more accurate estimates of DIN delivery to coastal oceans.
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Affiliation(s)
- Blair M Goodridge
- Bren School of Environmental Science & Management, University of California, Santa Barbara , Santa Barbara, California 93106, United States
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19
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Tait DR, Santos I, Maher D, Cyronak TJ, Davis RJ. Enrichment of radon and carbon dioxide in the open atmosphere of an Australian coal seam gas field. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:3099-3104. [PMID: 23444905 PMCID: PMC3621574 DOI: 10.1021/es304538g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 02/21/2013] [Accepted: 02/27/2013] [Indexed: 06/01/2023]
Abstract
Atmospheric radon ((222)Rn) and carbon dioxide (CO2) concentrations were used to gain insight into fugitive emissions in an Australian coal seam gas (CSG) field (Surat Basin, Tara region, Queensland). (222)Rn and CO2 concentrations were observed for 24 h within and outside the gas field. Both (222)Rn and CO2 concentrations followed a diurnal cycle with night time concentrations higher than day time concentrations. Average CO2 concentrations over the 24-h period ranged from ~390 ppm at the control site to ~467 ppm near the center of the gas field. A ~3 fold increase in maximum (222)Rn concentration was observed inside the gas field compared to outside of it. There was a significant relationship between maximum and average (222)Rn concentrations and the number of gas wells within a 3 km radius of the sampling sites (n = 5 stations; p < 0.05). A positive trend was observed between CO2 concentrations and the number of CSG wells, but the relationship was not statistically significant. We hypothesize that the radon relationship was a response to enhanced emissions within the gas field related to both point (well heads, pipelines, etc.) and diffuse soil sources. Radon may be useful in monitoring enhanced soil gas fluxes to the atmosphere due to changes in the geological structure associated with wells and hydraulic fracturing in CSG fields.
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Affiliation(s)
- Douglas R. Tait
- Centre for
Coastal Biogeochemistry,
School of Environment, Science and Engineering, Southern
Cross University, PO Box 157, Lismore, NSW, Australia,
2480
| | - Isaac
R. Santos
- Centre for
Coastal Biogeochemistry,
School of Environment, Science and Engineering, Southern
Cross University, PO Box 157, Lismore, NSW, Australia,
2480
| | - Damien
T. Maher
- Centre for
Coastal Biogeochemistry,
School of Environment, Science and Engineering, Southern
Cross University, PO Box 157, Lismore, NSW, Australia,
2480
| | - Tyler J. Cyronak
- Centre for
Coastal Biogeochemistry,
School of Environment, Science and Engineering, Southern
Cross University, PO Box 157, Lismore, NSW, Australia,
2480
| | - Rachael J. Davis
- Centre for
Coastal Biogeochemistry,
School of Environment, Science and Engineering, Southern
Cross University, PO Box 157, Lismore, NSW, Australia,
2480
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20
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Dimova NT, Swarzenski PW, Dulaiova H, Glenn CR. Utilizing multichannel electrical resistivity methods to examine the dynamics of the fresh water-seawater interface in two Hawaiian groundwater systems. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jc007509] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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21
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Ganguli PM, Conaway CH, Swarzenski PW, Izbicki JA, Flegal AR. Mercury speciation and transport via submarine groundwater discharge at a southern California coastal lagoon system. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:1480-1488. [PMID: 22283682 DOI: 10.1021/es202783u] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We measured total mercury (Hg(T)) and monomethylmercury (MMHg) concentrations in coastal groundwater and seawater over a range of tidal conditions near Malibu Lagoon, California, and used (222)Rn-derived estimates of submarine groundwater discharge (SGD) to assess the flux of mercury species to nearshore seawater. We infer a groundwater-seawater mixing scenario based on salinity and temperature trends and suggest that increased groundwater discharge to the ocean during low tide transported mercury offshore. Unfiltered Hg(T) (U-Hg(T)) concentrations in groundwater (2.2-5.9 pM) and seawater (3.3-5.2 pM) decreased during a falling tide, with groundwater U-Hg(T) concentrations typically lower than seawater concentrations. Despite the low Hg(T) in groundwater, bioaccumulative MMHg was produced in onshore sediment as evidenced by elevated MMHg concentrations in groundwater (0.2-1 pM) relative to seawater (∼0.1 pM) throughout most of the tidal cycle. During low tide, groundwater appeared to transport MMHg to the coast, resulting in a 5-fold increase in seawater MMHg (from 0.1 to 0.5 pM). Similarly, filtered Hg(T) (F-Hg(T)) concentrations in seawater increased approximately 7-fold during low tide (from 0.5 to 3.6 pM). These elevated seawater F-Hg(T) concentrations exceeded those in filtered and unfiltered groundwater during low tide, but were similar to seawater U-Hg(T) concentrations, suggesting that enhanced SGD altered mercury partitioning and/or solubilization dynamics in coastal waters. Finally, we estimate that the SGD Hg(T) and MMHg fluxes to seawater were 0.41 and 0.15 nmol m(-2) d(-1), respectively - comparable in magnitude to atmospheric and benthic fluxes in similar environments.
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Affiliation(s)
- P M Ganguli
- Earth and Planetary Sciences, University of California, Santa Cruz, California, United States.
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22
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de Weys J, Santos IR, Eyre BD. Linking groundwater discharge to severe estuarine acidification during a flood in a modified wetland. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:3310-3316. [PMID: 21370855 DOI: 10.1021/es104071r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Periodic acidification of waterways adjacent to coastal acid sulfate soils (CASS) is a significant land and water management issue in the subtropics. In this study, we use 5-months of continuous radon ((222)Rn, a natural groundwater tracer) observations to link estuarine acidification to groundwater discharge in an Australian CASS catchment (Tuckean Swamp). The radon time series began in the dry season, when radon activities were low (2-3 dpm L(-1)), and the pH of surface water was 6.4. We captured a major rain event (213 mm on 2 March 2010) that flooded the catchment. An immediate drop in pH during the flood may be attributed to surface water interactions with soil products. During the post-flood stage, increased radon activities (up to 19.3 dpm L(-1)) and floodplain groundwater discharge rates (up to 2.01 m(3) s(-1), equivalent to 19% of total runoff) coincided with low pH (3.77). Another spike in radon activities (13.2 dpm L(-1)) coincided with the lowest recorded surface water pH (3.62) after 72 mm of rain between 17 and 20 April 2010. About 80% of catchment acid exports occurred when the estuary was dominated by groundwater discharging from highly permeable CASS during the flood recession.
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Affiliation(s)
- Jason de Weys
- Centre for Coastal Biogeochemistry, School of Environmental Science and Management, Southern Cross University , P.O. Box 157, Lismore, New South Wales 2480, Australia
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23
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Dougherty JA, Swarzenski PW, Dinicola RS, Reinhard M. Occurrence of herbicides and pharmaceutical and personal care products in surface water and groundwater around Liberty Bay, Puget Sound, Washington. JOURNAL OF ENVIRONMENTAL QUALITY 2010; 39:1173-1180. [PMID: 20830904 DOI: 10.2134/jeq2009.0189] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Organic contaminants, such as pharmaceuticals and personal care products (PPCPs), pose a risk to water quality and the health of ecosystems. This study was designed to determine if a coastal community lacking point sources, such as waste water treatment plant effluent, could release PPCPs, herbicides, and plasticizers at detectable levels to their surface water and groundwater. Research was conducted in Liberty Bay, an embayment within Puget Sound, where 70% of the population (-10,000) uses septic systems. Sampling included collection of groundwater and surface water with grab samples and the use of polar organic chemical integrative samplers (POCIS). We analyzed for a broad spectrum of 25 commonly used compounds, including PPCPs, herbicides, and a flame retardant. Twelve contaminants were detected at least once; only N,N-diethyl-meta-toluamide, caffeine, and mecoprop, a herbicide not attributed to septic systems, were detected in more than one grab sample. The use of POCIS was essential because contaminants were present at very low levels (nanograms), which is common for PPCPs in general, but particularly so in such a small community. The use of POCIS allowed the detection of five compounds that were not present in grab samples. Data suggest that the community is contaminating local water with PPCPs; this effect is likely to increase as the population and product usage increase. The results presented here are a first step toward assessing the transport of herbicides and PPCPs into this coastal system.
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Affiliation(s)
- Jennifer A Dougherty
- Dep. of Civil and Environmental Engineering, Yang & Yamasaki Environment & Energy Bldg., 473 Via Ortega, Stanford Univ., Stanford, CA 94305, USA.
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Santos IR, Burnett WC, Chanton J, Dimova N, Peterson RN. Land or ocean?: Assessing the driving forces of submarine groundwater discharge at a coastal site in the Gulf of Mexico. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008jc005038] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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25
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Fritz BG, Mendoza DP, Gilmore TJ. Development of an electronic seepage chamber for extended use in a river. GROUND WATER 2009; 47:136-140. [PMID: 18793205 DOI: 10.1111/j.1745-6584.2008.00491.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Seepage chambers have been used to characterize the flux of water across the water-sediment interface in a variety of settings. In this work, an electronic seepage chamber was developed specifically for long-term use in a large river where hydraulic gradient reversals occur frequently with river-stage variations. A bidirectional electronic flowmeter coupled with a seepage chamber was used to measure temporal changes in the magnitude and direction of water flux across the water-sediment interface over an 8-week period. The specific discharge measured from the seepage chamber compared favorably with measurements of vertical hydraulic gradient and previous specific discharge calculations. This, as well as other supporting data, demonstrates the effectiveness of the electronic seepage chamber to accurately quantify water flux in two directions over a multimonth period in this setting. The ability to conduct multimonth measurements of water flux at a subhourly frequency in a river system is a critical capability for a seepage chamber in a system where hydraulic gradients change on a daily and seasonal basis.
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Affiliation(s)
- Brad G Fritz
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA 99352, USA.
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Peterson RN, Burnett WC, Taniguchi M, Chen J, Santos IR, Ishitobi T. Radon and radium isotope assessment of submarine groundwater discharge in the Yellow River delta, China. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008jc004776] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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27
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Stieglitz T, Rapaglia J, Bokuniewicz H. Estimation of submarine groundwater discharge from bulk ground electrical conductivity measurements. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jc004499] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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