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Tracing The Sources Of Nitrogen In Submarine Groundwater Discharge And Primary Producers In The Great South Bay Estuary, Nia H. Rene 2025 CUNY Graduate Center

Tracing The Sources Of Nitrogen In Submarine Groundwater Discharge And Primary Producers In The Great South Bay Estuary, Nia H. Rene

Dissertations, Theses, and Capstone Projects

The primary aim of this research was to elucidate the impact of submarine groundwater discharge (SGD) and septic effluent on coastal primary producers in the Great South Bay (GSB). The study focused on three main objectives: assessing the impact of precipitation patterns on SGD, tracing nitrogen sources into the GSB, and determining the impact of these nitrogen sources on coastal primary producers. The research revealed that current precipitation patterns significantly influence SGD across different seasons, highlighting the seasonal variability in groundwater discharge and its implications for nutrient loading in coastal waters. A suite of tracers was employed to identify and …


Global Estimates Of The Storage And Transit Time Of Water Through Vegetation, Andrew Felton, Joshua B. Fisher, Koen Hufkens, Adam J. Purdy, Seth A. Spawn-Lee, Lou F. Duloisy, Gregory R. Goldsmith 2025 Chapman University

Global Estimates Of The Storage And Transit Time Of Water Through Vegetation, Andrew Felton, Joshua B. Fisher, Koen Hufkens, Adam J. Purdy, Seth A. Spawn-Lee, Lou F. Duloisy, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The time it takes for water to transit from the ground back to the atmosphere affects weather, climate, biogeochemistry and ecosystem function. The transit time of water through vegetation, defined as the age of water transpiring from vegetation since time of entry, is a particularly understudied aspect of the terrestrial hydrologic cycle. Here we use a synergy of satellite remote sensing measurements over a five-year period to estimate global aboveground vegetation water storage to be on average 484 km3, roughly half of which is stored in Earth’s water-limited savannah, grassland and shrubland ecosystems. We then combine these storage …


Unveiling Hidden Mercury And Methylmercury Sources: The Role Of Submarine Groundwater Discharge In Coastal Lagoons, Céline Lavergne, Júlia Rodriguez-Puig, Clara Ruiz-González, Maria Montero-Curiel, Gemma Casas, Daniel Romano-Gude, Irene Alorda-Montiel, Júlia Dordal-Soriano, Aaron Alorda-Kleinglass, Marc Diego-Feliu, Javier Gilabert, Alex Campillo-de La Maza, Cristina Romera-Castillo, Natalia Torres-Rodriguez, Lars-Eric Heimbürger-Boavida, Jordi Garcia-Orellana, Valenti Rodellas, Andrea G. Bravo 2025 Universidad de Playa Ancha

Unveiling Hidden Mercury And Methylmercury Sources: The Role Of Submarine Groundwater Discharge In Coastal Lagoons, Céline Lavergne, Júlia Rodriguez-Puig, Clara Ruiz-González, Maria Montero-Curiel, Gemma Casas, Daniel Romano-Gude, Irene Alorda-Montiel, Júlia Dordal-Soriano, Aaron Alorda-Kleinglass, Marc Diego-Feliu, Javier Gilabert, Alex Campillo-De La Maza, Cristina Romera-Castillo, Natalia Torres-Rodriguez, Lars-Eric Heimbürger-Boavida, Jordi Garcia-Orellana, Valenti Rodellas, Andrea G. Bravo

OES Faculty Publications

Mercury loads from Submarine Groundwater Discharge (SGD) may represent an overlooked source of methylmercury (MeHg) to the ocean, affecting human and ecosystem health. The SGD process involves the flow of fresh, saline, or mixed groundwater from coastal aquifers into the oceans classified in different components. Existing studies rarely report the fluxes supplied by the different SGD components; therefore, the relevance of SGD as a source of mercury remains unclear. We aimed to quantify SGD-driven mercury/methylmercury fluxes to the coast, focusing on the largest coastal lagoon in the western Mediterranean. We measured total dissolved mercury and MeHg in surficial and porewaters …


Moderate Heating Renders 7.8-Million-Year-Old Sedimentary Organic Matter Bioavailable, Shuchai Gan, Verena B. Heuer, Frauke Schmidt, Lars Wormer, Faming Wang, Rishi R. Adhikari, Patrick Hatcher, Ann Pearson, Kai-Uwe Hinrichs 2025 University of Bremen

Moderate Heating Renders 7.8-Million-Year-Old Sedimentary Organic Matter Bioavailable, Shuchai Gan, Verena B. Heuer, Frauke Schmidt, Lars Wormer, Faming Wang, Rishi R. Adhikari, Patrick Hatcher, Ann Pearson, Kai-Uwe Hinrichs

Chemistry & Biochemistry Faculty Publications

Marine sediments are a large reservoir of recalcitrant organic matter and host microbes at subsurface depths exceeding 2.4 kilometers and temperatures up to 120°C, yet the mechanisms supplying bioavailable substrates remain unclear. Here, we investigated 7.8-million-year-old sediment from IODP Site C0012 off the Nankai Trough, Japan, through incubations at 20°, 35°, 55°, and 85°C to simulate burial temperatures. Using 3D fluorescence spectroscopy and ultrahigh-resolution mass spectrometry, we tracked changes in dissolved organic matter (DOM). At 35°C, humic-like DOM was released alongside metal ions, exhibiting low bioavailability. At 55°C, abiotic decomposition of humic compounds generated smaller, more bioavailable DOM, promoting fermentation. …


Impacts Of Southern Pine Beetle (Dendroctonus Frontalis Zimmerman) On Loblolly Pine (Pinus Taeda L.) Canopy And Water Use In The Homochitto National Forest, Mississippi, Usa, Sasha Goodnow, Yun Yang, Hui Liu, Ashley Schulz 2025 University of Missouri

Impacts Of Southern Pine Beetle (Dendroctonus Frontalis Zimmerman) On Loblolly Pine (Pinus Taeda L.) Canopy And Water Use In The Homochitto National Forest, Mississippi, Usa, Sasha Goodnow, Yun Yang, Hui Liu, Ashley Schulz

Endeavors: Mississippi State Undergraduate Research Journal

Abiotic and biotic forest disturbances can have many impacts to forest ecosystem services, including to forest water use. Studies on impacts to forest evapotranspiration have been conducted on the mountain pine beetle (Dendroctonus ponderosae) in western North America, but not on the southern pine beetle (Dendroctonus frontalis), which is a native pest of loblolly pine (Pinus taeda) and shortleaf pine (Pinus echinata), in the southeastern United States. Stressed pine trees produce pheromones that attract southern pine beetles and, with enough stressed trees, beetle populations can quickly grow to epidemic levels and attack healthy trees, which results in widespread tree mortality. …


Advancing Root Trait Measurements For A Deeper Understanding Of Soil Biogeochemistry, Brian Rinehart 2025 University of Kentucky

Advancing Root Trait Measurements For A Deeper Understanding Of Soil Biogeochemistry, Brian Rinehart

Theses and Dissertations--Plant and Soil Sciences

Climate change is disrupting (agro)ecosystems, with the potential for significant losses in crop productivity and ecosystem resilience due to changes in water and biogeochemical cycling. These disruptions can also release more carbon dioxide into the atmosphere through the degradation of soil organic matter. Plant roots have emerged as a potential tool for mitigating these effects, given their roles in plant function and in driving soil biogeochemistry. While this interest is growing, our ability to implement root trait selection is limited due to constraints on characterizing roots and limited clarity on the effects of traits on plant and ecosystem function. My …


Elucidating Non-Canonical Interactions Of Mcl1 With The P53 Family Of Tumor Suppressors, Alexus Marie Acton 2025 University of Alabama at Birmingham

Elucidating Non-Canonical Interactions Of Mcl1 With The P53 Family Of Tumor Suppressors, Alexus Marie Acton

All ETDs from UAB

Various signaling mechanisms contribute to a cancers cell’s ability to survive through the stressors of tumorigenesis. Canonically, when a cell is exposed to irreversible stress, the induction to apoptosis is regulated by the Bcl-2 family of apoptotic regulators. However, to accommodate for the stressors of tumor progression, many solid tumors over express one of the pro-survival proteins (e.g., BCL2, BCLxL, MCL1) allowing for persistent growth without the induction to cell death. Over the past 10 years, researchers have investigated how over expression of these pro-survival proteins contribute to chemoresistance to standard of care therapies. To sensitize cells to these apoptotic …


A Biogeochemical Perspective On Acidification And Buffering Capacity In The Piscataqua Estuary, Sanjana Varanasi 2025 University of New Hampshire, Durham

A Biogeochemical Perspective On Acidification And Buffering Capacity In The Piscataqua Estuary, Sanjana Varanasi

Master's Theses and Capstones

Coastal acidification is influenced not only by rising atmospheric CO2 and river-ocean mixing, but also by metabolic processes that alter seawater carbonate chemistry and buffering capacity. This study examines how sedimentary biogeochemical processes contribute to carbonate system variability in the Piscataqua Estuary, a tidally dynamic channel connecting Great Bay to the Gulf of Maine. The biogeochemical processes considered include sedimentary aerobic respiration, denitrification, sulfate reduction, and carbonate dissolution or precipitation. Two incubation experiments were conducted in September and October of 2024 at the University of New Hampshire’s Coastal Marine Laboratory (CML) to quantify changes in pH, dissolved inorganic carbon (DIC), …


Organic Carbon Decay Mediated By A Mesopelagic Microbial Community: The Relevance Of Carbon Pools And Broad Biochemical Composition, Noah J. Craft, Alexander B. Bochdansky 2025 Old Dominion University

Organic Carbon Decay Mediated By A Mesopelagic Microbial Community: The Relevance Of Carbon Pools And Broad Biochemical Composition, Noah J. Craft, Alexander B. Bochdansky

OES Faculty Publications

The mesopelagic zone is a site of strong microbially driven particle attenuation with depth and thus plays a crucial role in controlling the transfer efficiency of the ocean's biological pump. However, little quantitative information exists on the dependency of decay processes on the source material. Here we followed the decay of ¹⁴C-labeled dead particulate organic carbon (POC) and dissolved organic carbon (DOC) from three different phytoplankton species, and two incubations of live diatoms, in mesopelagic water over 3 months. Commonly used first-order kinetics failed to adequately describe the decay of organic material as rate constants varied from day to day. …


Dust Deposition To The Sargasso Sea: A Comparison Of Estimates Using Aluminum In The Surface Ocean Versus Aerosols And Rainwater, T. E. Williams, P. N. Sedwick, B. M. Sohst, K. N. Buck, S. Caprara, R. J. Johnson, D. C. Ohnemus, J. A. Resing, L. E. Sofen, A. Tagliabue, B. S. Twining 2025 Old Dominion University

Dust Deposition To The Sargasso Sea: A Comparison Of Estimates Using Aluminum In The Surface Ocean Versus Aerosols And Rainwater, T. E. Williams, P. N. Sedwick, B. M. Sohst, K. N. Buck, S. Caprara, R. J. Johnson, D. C. Ohnemus, J. A. Resing, L. E. Sofen, A. Tagliabue, B. S. Twining

OES Faculty Publications

As a major component of mineral aerosol that partially dissolves in seawater, aluminum (Al) has been used to estimate time-averaged dust fluxes to the ocean, based on dissolved aluminum (DAl) concentrations and an assumed replacement time of DAl (tau DAl) in the surface mixed layer, along with the fractional solubility (Als) and mass abundance of Al in dust. We apply this method in the Bermuda region using seasonal water-column DAl concentrations, and compare our results with fluxes estimated from Al measured in Bermuda aerosols and rain. Inventories of DAl over the maximum mixed-layer depth of 200 m and empirically derived …


Evidence Of Mineral Alteration In A Salt Marsh Subterranean Estuary: Implications For Carbon And Trace Element Cycling, J. J. Tamborski, M. J. Eagle, M. T. Thorpe, M. A. Charette, B. L. Kurylyk, S. Rahman, K. D. Kroeger, J. O'Keefe Suttles, A. G. Mann, T. W. Brooks, Z. A. Wang 2025 Old Dominion University

Evidence Of Mineral Alteration In A Salt Marsh Subterranean Estuary: Implications For Carbon And Trace Element Cycling, J. J. Tamborski, M. J. Eagle, M. T. Thorpe, M. A. Charette, B. L. Kurylyk, S. Rahman, K. D. Kroeger, J. O'Keefe Suttles, A. G. Mann, T. W. Brooks, Z. A. Wang

OES Faculty Publications

Subterranean estuaries (STE) in salt marshes are biogeochemically active zones where interactions between terrestrial groundwater and seawater drive complex cycling of carbon and trace elements, influenced by mineral dissolution. These systems, characterized by fine-grained organic-rich peat overlying permeable coastal aquifers, play a crucial role as a blue carbon sink, yet their geochemical dynamics remain poorly understood. We investigated dissolved trace elements, carbon, silica, and radium isotopes in a salt marsh STE (Sage Lot Pond, Waquoit Bay, MA) over seasonal and annual cycles. Our results reveal that groundwater and estuarine water circulation through marsh peat and aquifer sediments leads to enrichments …


The Δ¹³C Signature Of Dissolved Organic And Inorganic Carbon Reveals Complex Carbon Transformations Within A Salt Marsh, Meagan J. Eagle, Kevin D. Kroeger, John W. Pohlman, Joseph J. Tamborski, Zhaohui Aleck Wang, T. W. Brooks, Jennifer O. Keefe Suttles, Adrian Mann 2025 Woods Hole Coastal and Marine Science Center

The Δ¹³C Signature Of Dissolved Organic And Inorganic Carbon Reveals Complex Carbon Transformations Within A Salt Marsh, Meagan J. Eagle, Kevin D. Kroeger, John W. Pohlman, Joseph J. Tamborski, Zhaohui Aleck Wang, T. W. Brooks, Jennifer O. Keefe Suttles, Adrian Mann

OES Faculty Publications

Coastal wetlands have high rates of atmospheric CO₂ uptake, which is subsequently respired back to the atmosphere, stored as organic matter within flooded, anoxic soils, or exported to the coastal ocean. Transformation of fixed carbon occurs through a variety of subsurface aerobic and anaerobic microbial processes, and results in a large inventory of dissolved carbon. Carbon source and the roles of aerobic respiration, sulfate reduction, and methane cycling were evaluated within salt marsh peat and the underlying sandy subterranean estuary. There is a large increase in dissolved inorganic carbon (DIC, 7,350 ± 3,900 μmol L-¹), dissolved organic carbon …


Evaluation Of Practical Methods To Determine If A Karst Creek Is Gaining Or Losing: Case Study Of Leith Creek, Elizabeth Jones 2025 Missouri State University

Evaluation Of Practical Methods To Determine If A Karst Creek Is Gaining Or Losing: Case Study Of Leith Creek, Elizabeth Jones

Graduate Theses/Dissertations

Karst landscapes are abundant in Missouri, with features such as caves, springs, and sinkholes that form through the dissolution of limestone. Leith Creek is a small stream in Polk County, Missouri fed by two springs and the shallow unconfined Springfield Plateau aquifer, a highly karstified aquifer which is made up of limestone and minor interbedded shale-mudstone units. To determine if Leith Creek is gaining or losing, stream flow, water chemistry and temperature sensors were monitored. Stream flow results required multiple visits to take measurements while temperature sensors required two visits, one to install the dataloggers and another to remove the …


Investigating The Thermal Stratification Patterns Of A Shallow Polymictic Boreal Shield Lake And The Effectiveness Of Models In Predicting Shallow Lake Thermal Profiles, Matthew Roberts 2025 Wilfrid Laurier University

Investigating The Thermal Stratification Patterns Of A Shallow Polymictic Boreal Shield Lake And The Effectiveness Of Models In Predicting Shallow Lake Thermal Profiles, Matthew Roberts

Theses and Dissertations (Comprehensive)

Thermal stratification is a core process of lakes which plays a critical role in shaping the ecological dynamics of lakes, influencing major processes like nutrient cycling and oxygen availability. For shallow polymictic lakes, thermal stratification patterns present some unique differences due to the complex and variable nature of these lakes. In this thesis, I examined thermal stratification in a shallow polymictic lake in northwestern Ontario during the ice-free season of 2019 to investigate the frequency, duration, and driving factors of thermal stratification. The lake underwent 146 separate stratification events, with a median duration of 2 hours per event, with a …


A Collaborative Assessment Of Coastal Ocean Acidification Monitoring In Maine & Standard Operating Procedures And Best Practices For The Collection Of Continuous Ph Data In Coastal Marine Environments, Christopher W. Hunt, Curtis Bohlen, Mike Doan, Jeremy Miller 2025 Ocean Process Analysis Laboratory

A Collaborative Assessment Of Coastal Ocean Acidification Monitoring In Maine & Standard Operating Procedures And Best Practices For The Collection Of Continuous Ph Data In Coastal Marine Environments, Christopher W. Hunt, Curtis Bohlen, Mike Doan, Jeremy Miller

Faculty Publications

The ‘Sensor Squad’ of the Maine Ocean Climate Collaborative is the product of a 2023 Maine Coastal and Marine Climate Action Fund grant to conduct “A two-year pilot project designed to address and overcome technological barriers to ocean acidification data collection, develop protocols to elevate quality assurance and ensure comparable data, and meet regularly to discuss project results and data compilation”. The Squad consists of representatives from Friends of Casco Bay (FOCB), Wells National Estuarine Research Reserve (WNERR), and the University of New Hampshire (UNH). This report is a summary of their efforts to assess affordable, repeatable means of continuously …


Microbial Diversity And Biogeochemical Interactions In The Seismically Active And Co2-Rich Eger Rift Ecosystem, Daniel Lipus, Zeyu Jia, Megan Sondermann, Robert Bussert, Alexander Bartholomäus, Sizhong Yang, Dirk Wagner, Jens Kallmeyer 2024 Thomas Jefferson University

Microbial Diversity And Biogeochemical Interactions In The Seismically Active And Co2-Rich Eger Rift Ecosystem, Daniel Lipus, Zeyu Jia, Megan Sondermann, Robert Bussert, Alexander Bartholomäus, Sizhong Yang, Dirk Wagner, Jens Kallmeyer

College of Life Sciences Faculty Papers

The Eger Rift subsurface is characterized by frequent seismic activity and consistently high CO2 concentrations, making it a unique deep biosphere ecosystem and a suitable site to study the interactions between volcanism, tectonics, and microbiological activity. Pulses of geogenic H2 during earthquakes may provide substrates for methanogenic and chemolithoautotrophic processes, but very little is currently known about the role of subsurface microorganisms and their cellular processes in this type of environment. To assess the impact of geologic activity on microbial life, we analyzed the geological, geochemical, and microbiological composition of rock and sediment samples from a 238 m deep drill …


Organic Alkalinity Distributions, Characteristics, And Application To Carbonate System Calculations In Estuarine And Coastal Systems, Christopher W. Hunt, Joseph Salisbury, Xuewu Liu, Robert H. Byrne 2024 University of New Hampshire

Organic Alkalinity Distributions, Characteristics, And Application To Carbonate System Calculations In Estuarine And Coastal Systems, Christopher W. Hunt, Joseph Salisbury, Xuewu Liu, Robert H. Byrne

Faculty Publications

The capacity of aquatic systems to buffer acidification depends on the sum contributions of various chemical species to total alkalinity (TA). Major TA contributors are inorganic, with carbonate and bicarbonate considered the most important. However, growing evidence shows that many rivers, estuaries, and coastal waters contain dissolved organic molecules with charge sites that create organic alkalinity (OrgAlk). This study describes the first comparison of (1) OrgAlk distributions and (2) acid–base properties in contrasting estuary-plume systems: the Pleasant (Maine, USA) and the St. John (New Brunswick, CA). The substantial concentrations of OrgAlk in each estuary were sometimes not conservative with salinity …


Algal Community Investigations: Present Day To Year-2100 For Mississippi Lakes And The Western Mississippi Sound, Emma Madison Tucker 2024 Mississippi State University

Algal Community Investigations: Present Day To Year-2100 For Mississippi Lakes And The Western Mississippi Sound, Emma Madison Tucker

Theses and Dissertations

Algae play a key role in the aquatic environment as primary producers; however, they can form harmful algal blooms that are detrimental to the aquatic environment, people, and even the economy. It is generally believed that climate change will influence future algal blooms. The first study estimated algae community in three freshwater locations in Mississippi, Desoto Lake, White’s Creek Lake, and Columbus Lake, and one saline location, Western Mississippi Sound, using modern and new tools of the autonomous surface vessel, FlowCam, and EcoTaxa. From those results and leading into the second study was the application of four climate scenarios on …


The Ecology Of Chemosynthesis In Submerged Coastal Caves, Robert Scharping, Michael Casso, Isabel Schaal, Paul Henderson, James Garey, Matthew Charette, John Pohlman, Stefan Sievert 2024 University of Florida, Gainesville, USA

The Ecology Of Chemosynthesis In Submerged Coastal Caves, Robert Scharping, Michael Casso, Isabel Schaal, Paul Henderson, James Garey, Matthew Charette, John Pohlman, Stefan Sievert

FRONTIERS UNBOUND: Exploring Extreme Environments

No abstract provided.


Time-Transgressive Microbial Diversity In A Tropical Bat Guano Accumulation, Deer Cave, Mulu, Borneo, Joyce Lundberg, Donald A. McFarlane 2024 Carleton University, Canada

Time-Transgressive Microbial Diversity In A Tropical Bat Guano Accumulation, Deer Cave, Mulu, Borneo, Joyce Lundberg, Donald A. Mcfarlane

International Journal of Speleology

Bat guano accumulations in caves can constitute large deposits of organic material, particularly chitin and its degradation products, that host a diverse microbiome. Previous microbiological studies have not addressed the stratified nature of these deposits in the context of the timeframe of the decomposition process. We present such data (temperature, pH, DNA sampling of eight carbon-dated strata) for a 75 cm-deep tropical guano accumulation that undergoes complete decomposition over a timescale of ~120 years. The aerobic, surface layer of freshly-fallen guano has the greatest diversity of taxa, with Bacteroidota co-dominant with Pseudomonadota, and includes many taxa unique to this …


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