Article
Environmental Sciences
Elisa Calvo-Martin, Xose Anton Alvarez-Salgado, Carlos Rocha, J. Severino Pino Ibanhez
Summary: Subterranean estuaries are zones where continental groundwaters and saltwaters meet, impacting nutrient fluxes to coastal areas. Two STEs in NW Iberian Peninsula were studied for nitrogen biogeochemistry, showing seasonal water circulation variations and contrasting roles as nitrogen sinks or sources. The presence of gravel layers alters the typical structure of STEs, affecting nitrate concentrations and groundwater-borne nitrogen fluxes to the coast.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
Roisin McCallum, Bradley Eyre, Glenn Hyndes, Kathryn McMahon, Joanne M. Oakes, Naomi S. Wells
Summary: Estuaries and their catchments play a crucial role in the cycling of dissolved organic matter and nutrients, with ICOLLs impacting the biogeochemical processes and release of nitrogen and carbon into coastal environments. Despite low inorganic nitrogen concentrations, the eutrophic ICOLL studied in southwest Australia experiences issues such as algal blooms and low dissolved oxygen, highlighting the importance of considering dissolved organic nitrogen in nitrogen studies. Including dissolved organic nitrogen in nitrogen studies may have a significant impact on the current understanding of the global nitrogen budget.
Article
Environmental Sciences
Ke Pan, Wenlu Lan, Tianshen Li, Ming Hong, Xiaoyan Peng, Zhifang Xu, Wenjing Liu, Hao Jiang
Summary: Although the role of oysters in remediating estuarine eutrophication has been controversial, this study found that oysters can effectively suppress phytoplankton blooms in a nutrient-enriched estuary, impacting pelagic nitrogen cycling significantly. The research provides implications for restoring oyster reefs to mitigate the symptoms of estuarine eutrophication.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Geosciences, Multidisciplinary
Chun Ngai Chan, Cheuk Lam Tsang, Frederick Lee, Boyi Liu, Lishan Ran
Summary: High-gradient headwater streams play a significant role in the carbon (C) cycle, emitting a substantial amount of CO2; the pCO2 in the stream water in the upper reach is much higher than ambient levels, demonstrating a potentially large emission of CO2 into the atmosphere within a short distance; in addition to rapid gas exchange, temperature-dependent metabolism and decomposition of organic matter in soil may modulate the carbon dynamics in headwater streams.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Limnology
Louise C. V. Rewrie, Yoana G. Voynova, Justus E. E. van Beusekom, Tina Sanders, Arne Koertzinger, Holger Brix, Gregor Ollesch, Burkard Baschek
Summary: Estuaries play a crucial role in regulating carbon cycling and influencing carbon export to the ocean. The Elbe Estuary in Germany has undergone significant anthropogenic perturbations, resulting in heavy metal pollution, untreated wastewater, and subsequent improvements in water quality. This study identified three ecosystem states in recent history: polluted, transitional, and recovery states, characterized by different levels of dissolved inorganic carbon, heavy metal concentrations, and primary production. It was found that large anthropogenic perturbations can alter estuarine ecosystems and induce complex shifts in carbon cycling.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Article
Environmental Sciences
Josianne Haag, Henrietta Dulai, William Burt
Summary: The major sources of macronutrients in Jakolof Bay in Alaska are submarine groundwater discharge, rivers, and offshore water. This study challenges the assumption that offshore water is the major input of macronutrients by determining the relative contribution of macronutrients from submarine groundwater discharge. It is found that submarine groundwater discharge dominates the input of silicic acid and contends with offshore waters as the primary sources of nitrate in this coastal area.
ESTUARIES AND COASTS
(2023)
Article
Environmental Sciences
Mohammad Atif Khan, Sanjeev Kumar, Rajdeep Roy, Satya Prakash, Aneesh A. Lotliker, Sanjiba Kumar Baliarsingh
Summary: The potential effects of tidal and diel cycles on carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) concentrations and fluxes in tropical estuaries are poorly understood. This study conducted sampling for nine consecutive days in the Mahanadi estuary of India and found that tidal forcing affected CO2 and CH4 concentrations, with higher concentrations during low tide. CO2 concentrations increased with decrease in tidal height, possibly due to higher freshwater contribution. N2O showed no significant variability with tidal cycle or water level fluctuation. The study area was a source of greenhouse gases to the atmosphere, except for the offshore region.
MARINE POLLUTION BULLETIN
(2023)
Article
Environmental Sciences
S. Krishna Niveditha, C. K. Haridevi, Revati Hardikar, Anirudh Ram
Summary: This study examines the phytoplankton assemblage and chlorophyll a along the salinity gradient and oxygen zonation in Ulhas Estuary. The results show that the estuary experiences oxic conditions in the euhaline region due to oxygenated coastal waters, while the poly-meso-oligohaline region is hypoxic because of pollution from industrial effluents, domestic/sewage, and agricultural discharges. Anthropogenic nutrients also contribute to phytoplankton biomass and hypoxia. The study finds that diatoms dominate in the euhaline-oxic region, but their contribution decreases significantly in the oligohaline region. Cyanophytes and chlorophytes govern the meso to oligohaline region due to their tolerance for low salinity and high dissolved inorganic nutrients. The Carlson's Trophic State Index further confirms the estuary's eutrophic state, and the study identifies the adaptation of cyanophytes and chlorophytes to oxygen-deficient water.
MARINE POLLUTION BULLETIN
(2022)
Article
Environmental Sciences
Praktan D. Wadnerkar, Bayartungalag Batsaikhan, Stephen R. Conrad, Kay Davis, Rogger E. Correa, Ceylena Holloway, Shane A. White, Christian J. Sanders, Isaac R. Santos
Summary: This study found that canal estate development affects saline groundwater exchange and related nutrient fluxes. Groundwater exchange rates in canals were higher than in mangrove creeks, and lateral fluxes of total dissolved nitrogen were comparable between canals and mangrove creeks. However, groundwater flows into canals released five times more total dissolved nitrogen than mangroves, indicating that mangroves are more efficient at retaining nitrogen.
ESTUARIES AND COASTS
(2021)
Article
Environmental Sciences
Leon Serre-Fredj, Leo Chasselin, Orianne Jolly, Pascal Claquin
Summary: The Seine estuary is a typical model of a system where reducing phosphorus (P) inputs alone led to nutrient balance disturbance and the presence of massive blooms. Sampling and analysis of the estuary revealed that light availability and nutrient concentrations, especially in late spring and summer, were the main drivers of primary production and phytoplankton dynamics. The blooms observed in a specific area of the estuary were attributed to the local effect of tide slowdown, while the role of phosphate as a limiting nutrient was not clear.
FRONTIERS IN ENVIRONMENTAL SCIENCE
(2023)
Article
Environmental Sciences
Rogger E. Correa, M. Bayani Cardenas, Raymond S. Rodolfo, Mark R. Lapus, Kay L. Davis, Anna B. Giles, Jose C. Fullon, Mithra-Christin Hajati, Nils Moosdorf, Christian J. Sanders, Isaac R. Santos
Summary: Submarine groundwater discharge can have significant impacts on coral reefs, especially in volcanically active areas. A study in the Philippines found that hydrothermal SGD led to a substantial increase in CO2 flux from groundwater, making the coral reef a source of CO2 emissions to the atmosphere and nearby waters.
Article
Environmental Sciences
S. Sukanya, Jacob Noble, Sabu Joseph
Summary: This paper reviews the advanced techniques for measuring dissolved radon in water and its applications as a tracer and precursor. Radon, with its short half-life, inertness, and sensitivity to subsurface conditions, is found to be a reliable tracer in water resources domain compared to seismic precursory studies. It has various applications in hydrogeological and geological studies, such as understanding surface water - groundwater interactions, estimating Submarine Groundwater Discharge (SGD), and locating geological structures.
Article
Green & Sustainable Science & Technology
Marko Cvetkovic, Josipa Kapuralic, Marija Pejic, Iva Kolenkovic Mocilac, David Rukavina, Duje Smircic, Ana Kamenski, Bojan Matos, Marko Spelic
Summary: The study used soil gas measurements and gamma-ray spectrometry to identify hydrocarbon migration pathways and surface oil seepage, confirming the method's applicability. Results show significant differences in soil gas analysis between different areas, distinguishing underground hydrocarbon accumulation areas and non-accumulation areas based on radon concentration and hydrocarbon gas detection.
Review
Environmental Sciences
Chidambaram Sabarathinam, Amjad Al-Rashidi, Bedour Alsabti, Dhanu Radha Samayamanthula, Umayadoss Saravana Kumar
Summary: The terrestrial hydrological cycle can be understood through the analysis of carbon isotopes in rainwater, surface water, and groundwater. This study reviews previous investigations on carbon isotopes in groundwater and precipitation, highlighting the lack of research on carbon storage and sequestration, as well as the lack of studies on δ13C of precipitation in arid regions. The need for integrated e-DNA investigations and research on the effects of dust storms on δ13C of rainfall in arid regions is emphasized to further understand the sources and processes of carbon compounds.
Article
Ecology
Avanti Acharya, Prasun Sanyal, Madhusudan Paul, Vandana Kumari Gupta, Sneha Bakshi, Pratap Bhattacharyya, Sandip Kumar Mukhopadhyay
Summary: This study describes the distribution of carbonate parameters in three estuaries of the Indian Sundarbans and examines the seasonal impacts on inorganic carbon parameters. The results suggest that primary production plays an important role in raising the concentrations of inorganic carbon parameters.
REGIONAL STUDIES IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
Rogger E. Correa, Kai Xiao, Stephen R. Conrad, Praktan D. Wadnerkar, Alicia M. Wilson, Christian J. Sanders, Isaac R. Santos
Summary: Groundwater fluxes release large amounts of carbon to the open ocean, exceeding surface water CO2 emissions and sediment carbon burial rates. The impact of salt marshes in carbon cycling depends on both their capacity to bury carbon and their potential to export carbon to the ocean via groundwater pathways.
ESTUARIES AND COASTS
(2022)
Article
Marine & Freshwater Biology
Rebecca L. L. Woodrow, Shane A. A. White, Christian J. J. Sanders, Ceylena J. J. Holloway, Praktan D. D. Wadnerkar, Stephen R. R. Conrad, James P. P. Tucker, Kay L. L. Davis, Isaac R. R. Santos
Summary: This study evaluates N2O emissions in an urban subtropical estuary in Australia, finding that flood events can lead to significant N2O emissions. The study also highlights the importance of considering both seasonal and episodic rainfall timeframes in estuarine N2O studies.
ESTUARINE COASTAL AND SHELF SCIENCE
(2022)
Article
Marine & Freshwater Biology
John A. O'Connor, Dirk Erler, Angus Ferguson, Damien T. Maher
Summary: The river's role in transporting and transforming terrestrial material to the sea is well-known. The tidal freshwater zone (TFZ), a mysterious stretch of river that oscillates along the daily tidal cycle without recording any salinity, is often overlooked. Limited studies have highlighted the TFZ's importance in removing and transforming terrestrial material, as well as being a hotspot for primary production and respiration. The TFZ's biogeochemical activity varies predictably based on the hydrologic state and affects the chemistry, water quality, and ecology of the saline estuarine reach. Therefore, conceptualizing the TFZ and estuary as a single entity influenced by both river and ocean forces is most appropriate.
ESTUARINE COASTAL AND SHELF SCIENCE
(2022)
Article
Ecology
Catherine E. Lovelock, Maria F. Adame, Jennifer Bradley, Sabine Dittmann, Valerie Hagger, Sharyn M. Hickey, Lindsay B. Hutley, Alice Jones, Jeffrey J. Kelleway, Paul S. Lavery, Peter Macreadie, Damien T. Maher, Soraya McGinley, Alice McGlashan, Sarah Perry, Luke Mosley, Kerrylee Rogers, James Z. Sippo
Summary: The restoration of coastal wetlands has the potential to provide climate change mitigation and adaptation benefits, support biodiversity, and offer additional ecosystem services. Developing rigorous methods for quantifying blue carbon sequestration during restoration is crucial.
RESTORATION ECOLOGY
(2022)
Article
Soil Science
Kai Xiao, Feng Pan, Isaac R. Santos, Yan Zheng, Chunmiao Zheng, Nengwang Chen, Zeyang Lu, Fenfang Wang, Zhenyang Li, Hailong Li
Summary: In this study, the impact of crab bioturbation on the redox geochemistry of iron, phosphate, and sulfide in coastal wetlands was investigated. The results showed that crab burrowing activities created deep depths for redox reactions and facilitated the coupling of Fe and S, leading to spatial variability in soil geochemistry. These findings highlight the importance of crab burrows in mediating the cycling of key elements in wetland ecosystems.
Article
Chemistry, Multidisciplinary
Douglas R. Tait, Michael J. Reading, Kylie Maguire, Anthony Kirk, Damien T. Maher, Charly A. Moras, Dirk Erler
Summary: Coral reef lagoons are being adversely affected by regional and global factors such as land runoff, ocean acidification, and excess algae growth. Groundwater inputs of CO2 and alkalinity, as well as stream flows, play significant roles in the acidification and regulation of these lagoons. However, while alkalinity inputs may reduce acidification, they do not fully counteract ongoing acidification and CO2 inputs.
Article
Limnology
Vanessa Solano, Clement Duvert, Christian Birkel, Damien T. T. Maher, Erica A. A. Garcia, Lindsay B. B. Hutley
Summary: This study used high-frequency measurements of dissolved O2 and CO2 concentrations to estimate the potential contribution of stream metabolism to the CO2 evasion flux in a tropical lowland headwater stream. The results showed that the stream was heterotrophic all year round, with positive net ecosystem productivity (NEP) values. Despite seasonal changes, the CO2 excess was likely transported downstream and emitted to the atmosphere.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Article
Environmental Sciences
Lewis Walden, Oscar Serrano, Mingxi Zhang, Zefang Shen, James Z. Sippo, Lauren T. Bennett, Damien T. Maher, Catherine E. Lovelock, Peter I. Macreadie, Connor Gorham, Anna Lafratta, Paul S. Lavery, Luke Mosley, Gloria M. S. Reithmaier, Jeffrey J. Kelleway, Sabine Dittmann, Fernanda Adame, Carlos M. Duarte, John Barry Gallagher, Pawel Waryszak, Paul Carnell, Sabine Kasel, Nina Hinko-Najera, Rakib Hassan, Madeline Goddard, Alice R. Jones, Raphael A. Viscarra Rossel
Summary: Multi-scale spatial machine learning is used to analyze soil carbon stocks in Australia's ecosystems, revealing eight bio-regions and their subregional drivers. These findings can inform strategies for conservation and climate change mitigation.
COMMUNICATIONS EARTH & ENVIRONMENT
(2023)
Article
Geosciences, Multidisciplinary
Lei Wang, Zhiheng Du, Zhiqiang Wei, Wei Ouyang, Damien T. Maher, Qian Xu, Cunde Xiao
Summary: The concentrations of CH4 and CO2 under ice in winter were 3-4 orders of magnitude higher than those in summer, and increased with the depth of the thermokarst lakes and ponds. The study suggested that CH4 and CO2 accumulation in winter should be considered when evaluating annual carbon budgets in thermokarst lakes and ponds on the Tibetan Plateau.
Article
Engineering, Environmental
Douglas R. Tait, Isaac R. Santos, Sebastien Lamontagne, James Z. Sippo, Ashley Mcmahon, Luke C. Jeffrey, Damien T. Maher
Summary: Rivers are not the only source of nutrients for the Great Barrier Reef; submarine groundwater discharge also plays a significant role. However, internal recycling processes still dominate the nutrient budget, suggesting the need for a shift in management focus to protect the reef from excess nutrients.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Limnology
Sebastian Euler, Luke C. Jeffrey, Damien T. Maher, Scott G. Johnston, Ryo Sugimoto, Douglas R. Tait
Summary: Mangroves are important ecosystems that have significant impacts on primary production, carbon sequestration, and greenhouse gas cycles in coastal sediments. Microorganisms, specifically bacteria and archaea, play key roles in these processes. However, there are uncertainties regarding the functional and spatial distributions of microorganisms in mangroves.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Article
Ecology
Catherine E. Lovelock, Maria Fernanda Adame, Sabine Dittmann, Valerie Hagger, Sharyn M. Hickey, Lindsay I. Hutley, Alice Jones, Jeffrey J. Kelleway, Paul S. Lavery, Peter I. Macreadie, Damien T. Maher, Luke Mosley, Kerrylee Rogers, James Z. Sippo
Summary: The Blue Carbon Accounting Model (BlueCAM) is a tool for tidal restoration projects in the Australian carbon market. However, it does not subtract allochthonous carbon from estimated net abatement. Despite this, BlueCAM is transparent, conservative, feasible, and consistent with international guidelines and Australian standards.
RESTORATION ECOLOGY
(2023)
Article
Microbiology
Sebastian Euler, Luke C. Jeffrey, Damien T. Maher, Scott G. Johnston, Ryo Sugimoto, Douglas R. Tait
Summary: Subterranean estuaries (STEs) are coastal biogeochemical reactors that provide unique habitats for microbial communities. This study used 16S rRNA amplicon sequencing to evaluate the spatial distribution of microbial communities involved in transforming greenhouse gases and nutrients in an STE. The results showed that methane-producing organisms were most prevalent at the terrestrial end, while nitrifying and ammonia-oxidizing bacteria were abundant in the mixing zone. The concentrations of methane, ammonium, and dissolved organic carbon all decreased significantly along the transect from land to ocean. This study highlights the hidden microbial zonation in STEs and emphasizes the importance of microbial transformations in nutrient and greenhouse gas fluxes to coastal ecosystems.
ENVIRONMENTAL MICROBIOLOGY
(2023)
Review
Ecology
Sheel Bansal, Irena F. Creed, Brian A. Tangen, Scott D. Bridgham, Ankur R. Desai, Ken W. Krauss, Scott C. Neubauer, Gregory B. Noe, Donald O. Rosenberry, Carl Trettin, Kimberly P. Wickland, Scott T. Allen, Ariane Arias-Ortiz, Anna R. Armitage, Dennis Baldocchi, Kakoli Banerjee, David Bastviken, Peter Berg, Matthew J. Bogard, Alex T. Chow, William H. Conner, Christopher Craft, Courtney Creamer, Tonya Delsontro, Jamie A. Duberstein, Meagan Eagle, M. Siobhan Fennessy, Sarah A. Finkelstein, Mathias Goeckede, Sabine Grunwald, Meghan Halabisky, Ellen Herbert, Mohammad M. R. Jahangir, Olivia F. Johnson, Miriam C. Jones, Jeffrey J. Kelleway, Sara Knox, Kevin D. Kroeger, Kevin A. Kuehn, David Lobb, Amanda L. Loder, Shizhou Ma, Damien T. Maher, Gavin McNicol, Jacob Meier, Beth A. Middleton, Christopher Mills, Purbasha Mistry, Abhijit Mitra, Courtney Mobilian, Amanda M. Nahlik, Sue Newman, Jessica L. O'Connell, Patty Oikawa, Max Post van der Burg, Charles A. Schutte, Changchun Song, Camille L. Stagg, Jessica Turner, Rodrigo Vargas, Mark P. Waldrop, Marcus B. Wallin, Zhaohui Aleck Wang, Eric J. Ward, Debra A. Willard, Stephanie Yarwood, Xiaoyan Zhu
Summary: Wetlands have a significant impact on global carbon sequestration, CO2 and methane emissions, and aquatic carbon fluxes. However, measuring wetland carbon is challenging due to the complexity and dynamism of the underlying biogeochemical processes. This review summarizes common and cutting-edge approaches for quantifying wetland carbon pools and fluxes, providing insights into measurement components, spatial and temporal representation, implementation considerations, and ancillary measurements.
Article
Plant Sciences
Luke C. Jeffrey, Scott G. Johnston, Douglas R. Tait, Johannes Dittmann, Damien T. Maher
Summary: This study investigates the role of tree bark in methane transport in lowland forests. The experiments reveal the presence of rapid "between-bark" methane transport in Melaleuca quinquenervia, while Casuarina glauca exhibits slower "through-bark" gas transportation dominated by diffusion.