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Full-Text Articles in Physical Sciences and Mathematics

Leveraging The Interdependencies Between Barrier Islands And Backbarrier Saltmarshes To Enhance Resilience To Sea-Level Rise, Christopher J. Hein, Michael S. Fenster, Keryn B. Gedan, Jeff R. Tabar, Emily A. Hein, Todd Demunda Sep 2021

Leveraging The Interdependencies Between Barrier Islands And Backbarrier Saltmarshes To Enhance Resilience To Sea-Level Rise, Christopher J. Hein, Michael S. Fenster, Keryn B. Gedan, Jeff R. Tabar, Emily A. Hein, Todd Demunda

VIMS Articles

Barrier islands and their backbarrier saltmarshes have a reciprocal relationship: aeolian and storm processes transport sediment from the beaches and dunes to create and build marshes along the landward fringe of the island. In turn, these marshes exert a stabilizing influence on the barrier by widening the barrier system and forming a platform onto which the island migrates, consequently slowing landward barrier migration and inhibiting storm breaching. Here, we present a novel framework for applying these natural interdependencies to managing coastal systems and enhancing barrier-island resilience. Further, we detail application of these principles through a case study of the design …


Membrane Inlet Mass Spectrometry Method (Reox/Mims) To Measure 15n-Nitrate In Isotope-Enrichment Experiments, Xianbiao Lin, Kaijun Lu, Amber K. Hardison, Et Al Jul 2021

Membrane Inlet Mass Spectrometry Method (Reox/Mims) To Measure 15n-Nitrate In Isotope-Enrichment Experiments, Xianbiao Lin, Kaijun Lu, Amber K. Hardison, Et Al

VIMS Articles

Using 15N stable isotope as a tracer to quantify N transformation rates in isotope-enrichment experiments improves understanding of the N cycle in various ecosystems. However, measuring 15N-nitrate (15NO3) in small volumes of water for these experiments is a major challenge due to the inconvenience of preparing samples by traditional techniques. We developed a “REOX/MIMS” method by applying membrane inlet mass spectrometry (MIMS) to determining 15NO3 concentrations in a small volumes of water from isotope-enrichment experiments after converting the dissolved inorganic N to N2. The nitrates (NO3− …


Nonlinearity Of Subtidal Estuarine Circulation In The Pearl River Estuary, China, Hongzhou Xu, Jian Shen, Dongxiao Wang, Lin Luo, Bo Hong Jun 2021

Nonlinearity Of Subtidal Estuarine Circulation In The Pearl River Estuary, China, Hongzhou Xu, Jian Shen, Dongxiao Wang, Lin Luo, Bo Hong

VIMS Articles

The Pearl River Estuary (PRE) is a bell-shaped estuary with a narrow deep channel and wide shoals. This unique topographic feature leads to different dynamics of the subtidal estuarine circulation (SEC) in the PRE compared with a narrow and straight estuary. In this study, the nonlinear dynamics of the SEC in the PRE under mean circumstance are analyzed by using a validated 3D numerical model. Model results show that the nonlinear advections reach leading order in the along-channel momentum balance. Modulated by tide, the nonlinear advections show significant temporal variations as they have much larger values during spring tide than …


Formation Of Oil-Particle-Aggregates: Numerical Model Formulation And Calibration, Linlin Cui, Courtney K. Harris, Danielle R.N. Tarpley May 2021

Formation Of Oil-Particle-Aggregates: Numerical Model Formulation And Calibration, Linlin Cui, Courtney K. Harris, Danielle R.N. Tarpley

VIMS Articles

When oil spills occur in turbid waters, the oil droplets and mineral grains can combine to form oil-particle aggregates (OPAs). The formation of OPAs impacts the vertical transport of both the oil and the mineral grains; especially increasing deposition of oil to the seabed. Though the coastal oceans can be very turbid, to date, few numerical ocean models have accounted for aggregation processes that form OPAs. However, interactions between oil and mineral aggregates may be represented using techniques developed to account for sediment aggregation. As part of Consortium for Simulation of Oil Microbial Interactions in the Ocean (CSOMIO), we modified …


Vegetation Type And Decomposition Priming Mediate Brackish Marsh Carbon Accumulation Under Interacting Facets Of Global Change, Anthony J. Rietl, J. Patrick Megonigal, Ellen R. Herbert, Matthew L. Kirwan Apr 2021

Vegetation Type And Decomposition Priming Mediate Brackish Marsh Carbon Accumulation Under Interacting Facets Of Global Change, Anthony J. Rietl, J. Patrick Megonigal, Ellen R. Herbert, Matthew L. Kirwan

VIMS Articles

Coastal wetland carbon pools are globally important, but their response to interacting facets of global change remain unclear. Numerical models neglect species-specific vegetation responses to sea level rise (SLR) and elevated CO2 (eCO2) that are observed in field experiments, while field experiments cannot address the long-term feedbacks between flooding and soil growth that models show are important. Here, we present a novel numerical model of marsh carbon accumulation parameterized with empirical observations from a long-running eCO2 experiment in an organic rich, brackish marsh. Model results indicate that eCO2 and SLR interact …


The Geomorphic Impact Of Mangrove Encroachment In An Australian Salt Marsh, Daniel J. Coleman, Kerrylee Rogers, D. Reide Corbett, Christopher J. Owers, Matthew L. Kirwan Apr 2021

The Geomorphic Impact Of Mangrove Encroachment In An Australian Salt Marsh, Daniel J. Coleman, Kerrylee Rogers, D. Reide Corbett, Christopher J. Owers, Matthew L. Kirwan

VIMS Articles

Mangroves are encroaching into salt marshes throughout the world as a result of environmental change. Previous studies suggest mangroves trap sediment more efficiently than adjacent salt marshes, providing mangroves greater capacity to adapt to sea level rise; this may occur by displacing salt marshes. However, sediment transport in adjacent marsh-mangrove systems and its role in mangrove encroachment upon salt marsh remain poorly understood. Here we directly test the hypothesis that mangroves reduce the ability of adjacent marsh to adjust to sea level rise by measuring sediment transport across salt marsh platforms, with and without 6 m of fringing mangroves at …


Quantifying Thresholds Of Barrier Geomorphic Change In A Cross-Shore Sediment-Partitioning Model, Daniel J. Ciarletta, Jennifer L. Miselis, Justin L. Shawler, Christopher J. Hein Mar 2021

Quantifying Thresholds Of Barrier Geomorphic Change In A Cross-Shore Sediment-Partitioning Model, Daniel J. Ciarletta, Jennifer L. Miselis, Justin L. Shawler, Christopher J. Hein

VIMS Articles

Barrier coasts, including barrier islands, beach-ridge plains, and associated landforms, can assume a broad spectrum of morphologies over multi-decadal scales that reflect conditions of sediment availability, accommodation, and relative sea-level rise. However, the quantitative thresholds of these controls on barrier-system behavior remain largely unexplored, even as modern sea-level rise and anthropogenic modification of sediment availability increasingly reshape the world's sandy coastlines. In this study, we conceptualize barrier coasts as sediment-partitioning frameworks, distributing sand delivered from the shoreface to the subaqueous and subaerial components of the coastal system. Using an idealized morphodynamic model, we explore thresholds of behavioral and morphologic change …


Development Of The Csomio Coupled Ocean-Oil-Sediment- Biology Model, Dmitry S. Dukhovskoy, Steven L. . Morey, (...), Courtney K. Harris, Et Al Mar 2021

Development Of The Csomio Coupled Ocean-Oil-Sediment- Biology Model, Dmitry S. Dukhovskoy, Steven L. . Morey, (...), Courtney K. Harris, Et Al

VIMS Articles

The fate and dispersal of oil in the ocean is dependent upon ocean dynamics, as well as transformations resulting from the interaction with the microbial community and suspended particles. These interaction processes are parameterized in many models limiting their ability to accurately simulate the fate and dispersal of oil for subsurface oil spill events. This paper presents a coupled ocean-oil-biology-sediment modeling system developed by the Consortium for Simulation of Oil-Microbial Interactions in the Ocean (CSOMIO) project. A key objective of the CSOMIO project was to develop and evaluate a modeling framework for simulating oil in the marine environment, including its …


Different Coastal Marsh Sites Reflect Similar Topographic Conditions Under Which Bare Patches And Vegetation Recovery Occur, Chen Wang, Lennert Schepers, Matthew L. Kirwan, Et Al Feb 2021

Different Coastal Marsh Sites Reflect Similar Topographic Conditions Under Which Bare Patches And Vegetation Recovery Occur, Chen Wang, Lennert Schepers, Matthew L. Kirwan, Et Al

VIMS Articles

The presence of bare patches within otherwise vegetated coastal marshes is sometimes considered to be a symptom of marsh dieback and the subsequent loss of important ecosystem services. Here we studied the topographical conditions determining the presence and revegetation of bare patches in three marsh sites with contrasting tidal range, sediment supply, and plant species: the Scheldt estuary (the Netherlands), Venice lagoon (Italy), and Blackwater marshes (Maryland, USA). Based on GIS (geographic information system) analyses of aerial photos and lidar imagery of high resolution (≤2×2 m pixels), we analyzed the topographic conditions under which bare patches occur, including their surface …


A Regional, Early Spring Bloom Of Phaeocystis Pouchetii On The New England Continental Shelf, Walker O. Smith Jr., Weifeng G. Zhang, Andrew Hirzel, Et Al Feb 2021

A Regional, Early Spring Bloom Of Phaeocystis Pouchetii On The New England Continental Shelf, Walker O. Smith Jr., Weifeng G. Zhang, Andrew Hirzel, Et Al

VIMS Articles

The genus Phaeocystis is distributed globally and has considerable ecological, biogeochemical, and societal impacts. Understanding its distribution, growth and ecological impacts has been limited by lack of extensive observations on appropriate scales. In 2018, we investigated the biological dynamics of the New England continental shelf and encountered a substantial bloom of Phaeocystis pouchetii. Based on satellite imagery during January through April, the bloom extended over broad expanses of the shelf; furthermore, our observations demonstrated that it reached high biomass levels, with maximum chlorophyll concentrations exceeding 16 μg L−1 and particulate organic carbon levels > 95 μmol L−1. Initially, the bloom was …


Coastal Forest Seawater Exposure Increases Stem Methane Concentration, Matthew J. Norwood, Nicholas Ward, (......), Matthew L. Kirwan, Anya Hopple, J. Patrick Megonigal Feb 2021

Coastal Forest Seawater Exposure Increases Stem Methane Concentration, Matthew J. Norwood, Nicholas Ward, (......), Matthew L. Kirwan, Anya Hopple, J. Patrick Megonigal

VIMS Articles

Methane (CH4) exchange between trees and the atmosphere has recently emerged as an important, but poorly quantified process regulating global climate. The sources (soil and/or tree) and mechanisms driving the increase of CH4 in trees and degassing to the atmosphere are inadequately understood, particularly for coastal forests facing increased exposure to seawater. We investigated the eco‐physiological relationship between tree stem wood density, soil and stem oxygen saturation (an indicator of redox state), soil and stem CH4 concentrations, soil and stem carbon dioxide (CO2) concentrations, and soil salinity in five forests along the United States …


Effects Of Reduced Shoreline Erosion On Chesapeake Bay Water Clarity, Jessica S. Turner, Pierre St-Laurent, Marjorie A.M. Friedrichs, Carl T. Friedrichs Jan 2021

Effects Of Reduced Shoreline Erosion On Chesapeake Bay Water Clarity, Jessica S. Turner, Pierre St-Laurent, Marjorie A.M. Friedrichs, Carl T. Friedrichs

VIMS Articles

Shoreline erosion supplies sediments to estuaries and coastal waters, influencing water clarity and primary production. Globally, shoreline erosion sediment inputs are changing with anthropogenic alteration of coastlines in populated regions. Chesapeake Bay, a prime example of such a system where shoreline erosion accounts for a large proportion of sediments entering the estuary, serves here as a case study for investigating the effects of changing sediment inputs on water clarity. Long-term increases in shoreline armoring have contributed to decreased erosional sediment inputs to the estuary, changing the composition of suspended particles in surface waters. This study examined the impact of shoreline …


Diatom Hotspots Driven By Western Boundary Current Instability, Hilde Oliver, Weifeng G. Zhang, Walker O. Smith Jr., Et Al Jan 2021

Diatom Hotspots Driven By Western Boundary Current Instability, Hilde Oliver, Weifeng G. Zhang, Walker O. Smith Jr., Et Al

VIMS Articles

Climatic changes have decreased the stability of the Gulf Stream (GS), increasing the frequency at which its meanders interact with the Mid-Atlantic Bight (MAB) continental shelf and slope region. These intrusions are thought to suppress biological productivity by transporting low-nutrient water to the otherwise productive shelf edge region. Here we present evidence of widespread, anomalously intense subsurface diatom hotspots in the MAB slope sea that likely resulted from a GS intrusion in July 2019. The hotspots (at ∼50 m) were associated with water mass properties characteristic of GS water (∼100 m); it is probable that the hotspots resulted from the …


Onset Of Runaway Fragmentation Of Salt Marshes, Orencio Duran Vinent, Ellen R. Herbert, Daniel J. Coleman, Joshua D. Himmelstein, Matthew L. Kirwan Jan 2021

Onset Of Runaway Fragmentation Of Salt Marshes, Orencio Duran Vinent, Ellen R. Herbert, Daniel J. Coleman, Joshua D. Himmelstein, Matthew L. Kirwan

VIMS Articles

Salt marshes are valuable but vulnerable coastal ecosystems that adapt to relative sea level rise (RSLR) by accumulating organic matter and inorganic sediment. The natural limit of these processes defines a threshold rate of RSLR beyond which marshes drown, resulting in ponding and conversion to open waters. We develop a simplified formulation for sediment transport across marshes to show that pond formation leads to runaway marsh fragmentation, a process characterized by a self-similar hierarchy of pond sizes with power-law distributions. We find the threshold for marsh fragmentation scales primarily with tidal range and that sediment supply is only relevant where …


Long-Term Trends In Chesapeake Bay Remote Sensing Reflectance: Implications For Water Clarity, Jessica S. Turner, Carl T. Friedrichs, Marjorie A.M. Friedrichs Jan 2021

Long-Term Trends In Chesapeake Bay Remote Sensing Reflectance: Implications For Water Clarity, Jessica S. Turner, Carl T. Friedrichs, Marjorie A.M. Friedrichs

VIMS Articles

While ecosystem health is improving in many estuaries worldwide following nutrient reductions, inconsistent trends in water clarity often remain. The Chesapeake Bay, a eutrophic estuary with a highly populated watershed, is a crucial testbed for these concerns. Improved efforts are needed to understand why some measurements of downstream estuarine water clarity appear to be uncorrelated with watershed management actions, and multiple metrics of clarity are needed to address this issue. To complement in situ measurements, satellite remote sensing provides an additional tool with which to assess long-term change in water clarity. In this study, remote sensing reflectance (Rrs) from the …


Experimental Tree Mortality Does Not Induce Marsh Transgression In A Chesapeake Bay Low-Lying Coastal Forest, David C. Walters, Joel A. Carr, (...), Matthew L. Kirwan, Et Al Jan 2021

Experimental Tree Mortality Does Not Induce Marsh Transgression In A Chesapeake Bay Low-Lying Coastal Forest, David C. Walters, Joel A. Carr, (...), Matthew L. Kirwan, Et Al

VIMS Articles

Transgression into adjacent uplands is an important global response of coastal wetlands to accelerated rates of sea level rise. “Ghost forests” mark a signature characteristic of marsh transgression on the landscape, as changes in tidal inundation and salinity cause bordering upland tree mortality, increase light availability, and the emergence of tidal marsh species due to reduced competition. To investigate these mechanisms of the marsh migration process, we conducted a field experiment to simulate a natural disturbance event (e.g., storm-induced flooding) by inducing the death of established trees (coastal loblolly pine, Pinus taeda) at the marsh-upland forest ecotone. After this simulated …


Sea Ice Suppression Of Co2 Outgassing In The West Antarctic Peninsula: Implications For The Evolving Southern Ocean Carbon Sink, E.H. Shadwick, O.A. De Meo, S. Schroeter, M.C. Arroyo, D.G. Martinson, H. Ducklow Jan 2021

Sea Ice Suppression Of Co2 Outgassing In The West Antarctic Peninsula: Implications For The Evolving Southern Ocean Carbon Sink, E.H. Shadwick, O.A. De Meo, S. Schroeter, M.C. Arroyo, D.G. Martinson, H. Ducklow

VIMS Articles

The Southern Ocean plays an important role in the uptake of atmospheric CO2. In seasonally ice-covered regions, estimates of air-sea exchange remain uncertain in part because of a lack of observations outside the summer season. Here we present new estimates of air-sea CO2 flux in the West Antarctic Peninsula (WAP) from an autonomous mooring on the continental shelf. In summer, the WAP is a sink for atmospheric CO2 followed by a slow return to atmospheric equilibrium in autumn and winter. Outgassing is almost entirely suppressed by ice cover from June through October, resulting in a modest …


Sea Level-Driven Marsh Migration Results In Rapid Net Loss Of Carbon, Alexander J. Smith, Matthew L. Kirwan Jan 2021

Sea Level-Driven Marsh Migration Results In Rapid Net Loss Of Carbon, Alexander J. Smith, Matthew L. Kirwan

VIMS Articles

Sea level rise alters coastal carbon cycling by driving the rapid migration of coastal ecosystems, salinization of freshwater systems, and replacement of terrestrial forests with tidal wetlands. Wetland soils accumulate carbon (C) at faster rates than terrestrial soils, implying that sea level rise may lead to enhanced carbon accumulation. Here, we show that carbon stored in tree biomass greatly exceeds carbon stored in adjacent marsh soils so that marsh migration reduces total carbon stocks by 50% in less than 100years. Continued marsh soil carbon accumulation may eventually offset forest carbon loss, but we estimate that the time for replacement is …


Sea-Ice Microbial Communities In The Central Arctic Ocean: Limited Responses To Short-Term Pco(2) Perturbations, Anders Torstensson, Andrew R. Margolin, Gordon M. Showalter, Walker O. Smith Jr., Elizabeth H. Shadwick, Et Al Jan 2021

Sea-Ice Microbial Communities In The Central Arctic Ocean: Limited Responses To Short-Term Pco(2) Perturbations, Anders Torstensson, Andrew R. Margolin, Gordon M. Showalter, Walker O. Smith Jr., Elizabeth H. Shadwick, Et Al

VIMS Articles

The Arctic Ocean is more susceptible to ocean acidification than other marine environments due to its weaker buffering capacity, while its cold surface water with relatively low salinity promotes atmospheric CO 2 uptake. We studied how sea-ice microbial communities in the central Arctic Ocean may be affected by changes in the carbonate system expected as a consequence of ocean acidification. In a series of four experiments during late summer 2018 aboard the icebreaker Oden, we addressed microbial growth, production of dissolved organic carbon (DOC) and extra- cellular polymeric substances (EPS), photosynthetic activity, and bacterial assemblage structure as sea-ice microbial communities …


The Importance Of Organic Content To Fractal Floc Properties In Estuarine Surface Waters: Insights From Video, Lisst, And Pump Sampling, Kelsey A. Fall, Carl T. Friedrichs, Grace M. Massey, David G. Bowers, S. Jarrell Smith Jan 2021

The Importance Of Organic Content To Fractal Floc Properties In Estuarine Surface Waters: Insights From Video, Lisst, And Pump Sampling, Kelsey A. Fall, Carl T. Friedrichs, Grace M. Massey, David G. Bowers, S. Jarrell Smith

VIMS Articles

To better understand the nature of flocs of varying organic content in estuarine surface waters, Laser in situ Scattering and Transmissometry, video settling, and pump sampling were deployed in the York River estuary. A new in situ method was developed to simultaneously solve the floc fractal dimension (F), primary particle size (d p ), and primary particle density (ρ p ) by fitting a simple fractal model to observations of effective floc density (∆ρ) as a function of floc diameter (d f ), while ensuring that the integrated particle size distribution was consistent with measurements of bulk apparent density (ρ …


The Effect Of Coastal Landform Development On Decadal-To Millennial-Scale Longshore Sediment Fluxes: Evidence From The Holocene Evolution Of The Central Mid-Atlantic Coast, Usa, Justin L. Shawler, Christopher J. Hein, Chloe A. Obara, Mahina G. Robbins, Sebastien Huot, Michael S. Fenster Jan 2021

The Effect Of Coastal Landform Development On Decadal-To Millennial-Scale Longshore Sediment Fluxes: Evidence From The Holocene Evolution Of The Central Mid-Atlantic Coast, Usa, Justin L. Shawler, Christopher J. Hein, Chloe A. Obara, Mahina G. Robbins, Sebastien Huot, Michael S. Fenster

VIMS Articles

The behavior of siliciclastic coastal systems is largely controlled by the interplay between accommodation creation and infilling. Factors responsible for altering sediment fluxes to and along open-ocean coasts include cross-shore mobilization of sediment primarily from tidal currents and storms as well as changes in alongshore transport rates moderated by changing wave conditions, river sediment inputs, artificial shoreline hardening and modification, and natural sediment trapping in updrift coastal landforms. This paper focuses on the latter relationships. To address understudied interactions between updrift coastal landforms and downdrift coastal behavior, we quantify the volume and fluxes of sediment trapped in the Assateague-Chincoteague-Wallops barrier-island …


Molluscan Aminostratigraphy Of The Us Mid-Atlantic Quaternary Coastal System: Implications For Onshore-Offshore Correlation, Paleochannel And Barrier Island Evolution, And Local Late Quaternary Sea-Level History, John F. Wehmiller, Laura L. Brothers, (...), Christopher J. Hein, Justin L. Shawler Jan 2021

Molluscan Aminostratigraphy Of The Us Mid-Atlantic Quaternary Coastal System: Implications For Onshore-Offshore Correlation, Paleochannel And Barrier Island Evolution, And Local Late Quaternary Sea-Level History, John F. Wehmiller, Laura L. Brothers, (...), Christopher J. Hein, Justin L. Shawler

VIMS Articles

The Quaternary record of the US Mid-Atlantic coastal system includes onshore emergent late Pleistocene shoreline deposits, offshore inner shelf and barrier island units, and paleovalleys formed during multiple glacial stage sea-level lowstands. The geochronology of this coastal system is based on uranium series, radiocarbon, amino acid racemization (AAR), and optically stimulated luminescence (OSL) methods. We report over 600 mollusk AAR results from 93 sites between northeastern North Carolina and the central New Jersey shelf, representing samples from both onshore cores or outcrops, sub-barrier and offshore cores, and transported shells from barrier island beaches. AAR age estimates are constrained by paired …


Mechanisms Of Pond Expansion In A Rapidly Submerging Marsh, Joshua Himmelstein, Orencio Duran Vinent, Stijn Temmerman, Matthew L. Kirwan Jan 2021

Mechanisms Of Pond Expansion In A Rapidly Submerging Marsh, Joshua Himmelstein, Orencio Duran Vinent, Stijn Temmerman, Matthew L. Kirwan

VIMS Articles

The development and expansion of ponds within otherwise vegetated coastal marshes is a primary driver of marsh loss throughout the world. Previous studies propose that large ponds expand through a wind wave-driven positive feedback, where pond edge erosion rates increase with pond size, whereas biochemical processes control the formation and expansion of smaller ponds. However, it remains unclear which mechanisms dominate at a given scale, and thus how, and how fast, ponds increase their size. Here, we use historical photographs and field measurements in a rapidly submerging microtidal marsh to quantify pond development and identify the processes involved. We find …


Revisiting The Ocean Color Algorithms For Particulate Organic Carbon And Chlorophyll-A Concentrations In The Ross Sea, Shuangling Chen, Walker O. Smith Jr., Xiaolei Yu Jan 2021

Revisiting The Ocean Color Algorithms For Particulate Organic Carbon And Chlorophyll-A Concentrations In The Ross Sea, Shuangling Chen, Walker O. Smith Jr., Xiaolei Yu

VIMS Articles

The Ross Sea is the most productive marginal sea in the Southern Ocean and plays an important role in carbon cycling. However, limited sampling of Chlorophyll-a (Chl) and particulate organic carbon (POC) concentrations from research expeditions constrains our understanding of the biogeochemical processes there. Satellites provide a useful tool for synoptic mapping of surface water properties on regional and global scales, yet the general applicability of the published algorithms in the Ross Sea is poorly known. Based on the data collected from 18 cruises in the past 20 years, we analyzed both the NASA standard and locally developed Chl and …


Biophysical Controls Of Marsh Soil Shear Strength Along An Estuarine Salinity Gradient, Megan N. Gillen, Tyler C. Messerschmidt, Matthew L. Kirwan Jan 2021

Biophysical Controls Of Marsh Soil Shear Strength Along An Estuarine Salinity Gradient, Megan N. Gillen, Tyler C. Messerschmidt, Matthew L. Kirwan

VIMS Articles

Sea-level rise, saltwater intrusion, and wave erosion threaten coastal marshes, but the influence of salinity on marsh erodibility remains poorly understood. We measured the shear strength of marsh soils along a salinity and biodiversity gradient in the York River estuary in Virginia to assess the direct and indirect im-pacts of salinity on potential marsh erodibility. We found that soil shear strength was higher in monospecific salt marshes (5–36 kPa) than in biodiverse freshwater marshes (4–8 kPa), likely driven by differences in below ground biomass. However, we also found that shear strength at the marsh edge was controlled by sediment characteristics, …


On The Human Appropriation Of Wetland Primary Production, James E. Cloern, Samuel M. Safran, Lydia Smith Vaughn, (...), Elizabeth A. Canuel, J.Letitia Grenier Jan 2021

On The Human Appropriation Of Wetland Primary Production, James E. Cloern, Samuel M. Safran, Lydia Smith Vaughn, (...), Elizabeth A. Canuel, J.Letitia Grenier

VIMS Articles

Humans are changing the Earth's surface at an accelerating pace, with significant consequences for ecosystems and their biodiversity. Landscape transformation has far-reaching implications including reduced net primary production (NPP) available to support ecosystems, reduced energy supplies to consumers, and disruption of ecosystem services such as carbon storage. Anthropogenic activities have reduced global NPP available to terrestrial ecosystems by nearly 25%, but the loss of NPP from wetland ecosystems is unknown. We used a simple approach to estimate aquatic NPP from measured habitat areas and habitat-specific areal productivity in the largest wetland complex on the USA west coast, comparing historical and …


Exchange Flow And Material Transport Along The Salinity Gradient Of A Long Estuary, Jilian Xiong, Jian Shen, Qubin Qin Jan 2021

Exchange Flow And Material Transport Along The Salinity Gradient Of A Long Estuary, Jilian Xiong, Jian Shen, Qubin Qin

VIMS Articles

Most estuaries are characterized by non-uniform axial topography with shallow shoals near the mouth. Previous studies have addressed the impacts of the axial topographic variations on mixing and estuarine circulations yet seldom on material transport and retention. This study investigates the longitudinal structure and mechanisms of exchange flow and material transport of Chesapeake Bay (CB), featuring a shallow sill in the lower bay, by applying total exchange flow (TEF) algorithm, tracer experiments, and partial residence time (PRT) using a validated 32-years numerical model simulation. A retention coefficient was adopted to quantify the material retention rate using two characteristic PRTs: with …


Global Blue Carbon Accumulation In Tidal Wetlands Increases With Climate Change, Faming Wang, Christian J. Sanders, (...), Matthew L. Kirwan, Et Al Jan 2021

Global Blue Carbon Accumulation In Tidal Wetlands Increases With Climate Change, Faming Wang, Christian J. Sanders, (...), Matthew L. Kirwan, Et Al

VIMS Articles

Coastal tidal wetlands produce and accumulate significant amounts of organic carbon (C) that help to mitigate climate change. However, previous data limitations have prevented a robust evaluation of the global rates and mechanisms driving C accumulation. Here, we go beyond recent soil C stock estimates to reveal global tidal wetland C accumulation and predict changes under relative sea level rise, temperature and precipitation. We use data from literature study sites and our new observations spanning wide latitudinal gradients and 20 countries. Globally, tidal wetlands accumulate 53.65 (95%CI: 48.52–59.01) Tg C yr−1, which is∼30% of the organic C buried on the …