%0 Conference Paper %B Coastal Sediments 2023Coastal Sediments 2023 %D 2023 %T FEEDING SALT MARSHES WITH COASTAL STORMS %A Wang, Ping %A Royer, Elizabeth %A Rosati, Julie D %A Fagherazzi, Sergio %A CORTESE, LUCA %B Coastal Sediments 2023Coastal Sediments 2023 %I WORLD SCIENTIFIC %C New Orleans, LA, USA %@ 978-981-12-7989-8 %G eng %U https://www.worldscientific.com/worldscibooks/10.1142/13358 %R 10.1142/1335810.1142/9789811275135_0228 %0 Journal Article %J Geophysical Research Letters %D 2023 %T Frequent Storm Surges Affect the Groundwater of Coastal Ecosystems %A Nordio, Giovanna %A Frederiks, Ryan %A Hingst, Mary %A Carr, Joel %A Kirwan, Matt %A Gedan, Keryn %A Michael, Holly %A Fagherazzi, Sergio %B Geophysical Research Letters %V 501815 %8 Apr-01-2024 %G eng %U https://onlinelibrary.wiley.com/doi/10.1029/2022GL100191 %N 133 %! Geophysical Research Letters %R 10.1029/2022GL100191 %0 Journal Article %J Journal of Hydrology %D 2023 %T Image-based machine learning for monitoring the dynamics of deltaic islands in the Atchafalaya River Delta Complex between 1991 and 2019 %A Yang, Jiangjie %A Dai, Zhijun %A Lou, Yaying %A Mei, Xuefei %A Fagherazzi, Sergio %B Journal of Hydrology %V 623 %P 129814 %8 Jan-08-2023 %G eng %U https://linkinghub.elsevier.com/retrieve/pii/S0022169423007564 %! Journal of Hydrology %R 10.1016/j.jhydrol.2023.129814 %0 Journal Article %J Sedimentology %D 2023 %T Large‐scale sedimentary shift induced by a mega‐dam in deltaic flats %A Wang, Jie %A Dai, Zhijun %A Fagherazzi, Sergio %A Lou, Yaying %A Mei, Xuefei %A Ma, Binbin %B Sedimentology %8 11-29-2023 %G eng %U https://onlinelibrary.wiley.com/doi/10.1111/sed.13168 %! Sedimentology %R 10.1111/sed.13168 %0 Journal Article %J Geophysical Research Letters %D 2023 %T Quantifying Flow Velocities in River Deltas via Remotely Sensed Suspended Sediment Concentration %A Donatelli, Carmine %A Passalacqua, Paola %A Wright, Kyle %A Salter, Gerard %A Lamb, Michael P. %A Jensen, Daniel %A Fagherazzi, Sergio %B Geophysical Research Letters %V 50 %8 Apr-02-2025 %G eng %U https://onlinelibrary.wiley.com/doi/10.1029/2022GL101392 %N 4 %! Geophysical Research Letters %R 10.1029/2022GL101392 %0 Journal Article %J Earth Surface Dynamics %D 2022 %T Biogeomorphic modeling to assess the resilience of tidal-marsh restoration to sea level rise and sediment supply %A Gourgue, Olivier %A van Belzen, Jim %A Schwarz, Christian %A Vandenbruwaene, Wouter %A Vanlede, Joris %A Belliard, Jean-Philippe %A Fagherazzi, Sergio %A Bouma, Tjeerd J. %A van de Koppel, Johan %A Temmerman, Stijn %X There is an increasing demand for the creation and restoration of tidal marshes around the world, as they provide highly valued ecosystem services. Yet restored tidal marshes are strongly vulnerable to factors such as sea level rise and declining sediment supply. How fast the restored ecosystem develops, how resilient it is to sea level rise, and how this can be steered by restoration design are key questions that are typically challenging to assess due to the complex biogeomorphic feedback processes involved. In this paper, we apply a biogeomorphic model to a specific tidal-marsh restoration project planned by dike breaching. Our modeling approach integrates tidal hydrodynamics, sediment transport, and vegetation dynamics, accounting for relevant fine-scale flow–vegetation interactions (less than 1 m2) and their impact on vegetation and landform development at the landscape scale (several km2) and in the long term (several decades). Our model performance is positively evaluated against observations of vegetation and geomorphic development in adjacent tidal marshes. Model scenarios demonstrate that the restored tidal marsh can keep pace with realistic rates of sea level rise and that its resilience is more sensitive to the availability of suspended sediments than to the rate of sea level rise. We further demonstrate that restoration design options can steer marsh resilience, as they affect the rates and spatial patterns of biogeomorphic development. By varying the width of two dike breaches, which serve as tidal inlets to the restored marsh, we show that a larger difference in the width of the two inlets leads to higher biogeomorphic diversity in restored habitats. This study showcases that biogeomorphic modeling can support management choices in restoration design to optimize tidal-marsh development towards sustainable restoration goals. %B Earth Surface Dynamics %V 10 %P 531–553 %G eng %U https://esurf.copernicus.org/articles/10/531/2022/ %R 10.5194/esurf-10-531-2022 %0 Journal Article %J Limnology and Oceanography %D 2022 %T Biotic and abiotic factors control the geomorphic characteristics of channel networks in salt marshes %A Liu, Zezheng %A Gourgue, Olivier %A Fagherazzi, Sergio %B Limnology and Oceanography %V 67 %P 89–101 %8 jan %G eng %U https://onlinelibrary.wiley.com/doi/10.1002/lno.11977 %R 10.1002/lno.11977 %0 Journal Article %J Earth Surface Processes and Landforms %D 2022 %T Fetch and distance from the bay control accretion and erosion patterns in Terrebonne marshes (Louisiana, USA) %A CORTESE, LUCA %A Fagherazzi, Sergio %K CRMS %K marsh accretion %K marsh erosion %K Mississippi River Delta Plain %K waves %X Wetlands in the Mississippi River Delta are rapidly degrading. Sea level rise and low sediment supply are widely recognized as the two main factors contributing to land-to-water conversion. To determine what marsh areas are more resilient, it is fundamental to identify the drivers that regulate marsh accretion and degradation. In this study, a combination of field data and aerial images is used to determine these drivers in Terrebonne Bay, Louisiana, USA. We find that accretion and degradation patterns depend on whether the marsh is located inland in a sheltered area or facing open water. In the first case, the distance to the nearby channel is important, because during flooding of the marsh platform more sediment is deposited in the proximity of channel banks. The accretion rates of marshes facing open water are high and correlate to fetch, a proxy for the ability of waves to resuspend bottom sediment. These areas are more resilient to sea level rise, but waves are also the main mechanism of degradation, as these marshes tend to degrade by edge erosion. Consequently, we propose a bimodal evolution trajectory of the marshes in Terrebonne Bay: marshes close to the bay and facing open water accrete rapidly but are affected by lateral erosion due to waves, whereas sheltered marshes accrete slowly and degrade in large swathes due to insufficient sediment supply. %B Earth Surface Processes and Landforms %V 47 %P 1455–1465 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1002/esp.5327 %R 10.1002/esp.5327 %0 Journal Article %J Science of The Total Environment %D 2022 %T Hydro-morphodynamics triggered by extreme riverine floods in a mega fluvial-tidal delta %A Wang, Jie %A Dai, Zhijun %A Fagherazzi, Sergio %A Zhang, Xiaohe %A Liu, Xiaoqiang %B Science of The Total Environment %V 809 %P 152076 %8 feb %G eng %U https://linkinghub.elsevier.com/retrieve/pii/S0048969721071527 %R 10.1016/j.scitotenv.2021.152076 %0 Journal Article %J Journal of Geophysical Research: Earth Surface %D 2022 %T Improving Channel Hydrological Connectivity in Coastal Hydrodynamic Models With Remotely Sensed Channel Networks %A Zhang, Xiaohe %A Wright, Kyle %A Passalacqua, Paola %A Simard, Marc %A Fagherazzi, Sergio %K channel geometry %K coastal numerical model %K cost function %K flow propagation %K model performance %K remote-sensed channel network %X Coastal wetlands are nourished by rivers and periodical tidal flows through complex, interconnected channels. However, in hydrodynamic models, channel dimensions with respect to model grid size and uncertainties in topography preclude the correct propagation of tidal and riverine signals. It is therefore crucial to enhance channel geomorphic connectivity and simplify sub-channel features based on remotely sensed networks for practical computational applications. Here, we utilize channel networks derived from diverse remote sensing imagery as a baseline to build a ∼10 m resolution hydrodynamic model that covers the Wax Lake Delta and adjacent wetlands (∼360 km2) in coastal Louisiana, USA. In this richly gauged system, intensive calibrations are conducted with 18 synchronous field-observations of water levels taken in 2016, and discharge data taken in 2021. We modify channel geometry, targeting realism in channel connectivity. The results show that a minimum channel depth of 2 m and a width of four grid elements (approximatively 40 m) are required to enable a realistic tidal propagation in wetland channels. The optimal depth for tidal propagation can be determined by a simplified cost function method that evaluates the competition between flow travel time and alteration of the volume of the channels. The integration of high spatial-resolution models and remote sensing imagery provides a general framework to improve models performance in salt marshes, mangroves, deltaic wetlands, and tidal flats. %B Journal of Geophysical Research: Earth Surface %V 127 %P e2021JF006294 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1029/2021JF006294 %R 10.1029/2021JF006294 %0 Journal Article %J Frontiers in Marine Science %D 2022 %T Long-term variations in water discharge and sediment load of the Pearl River Estuary: Implications for sustainable development of the Greater Bay Area %A Liu, Zezheng %A Fagherazzi, Sergio %A Liu, Xinhui %A Shao, Dongdong %A Miao, Chiyuan %A Cai, Yanzi %A Hou, Congyu %A Liu, Yeling %A Li, Xia %A Cui, Baoshan %X The water discharge and sediment load have been increasingly altered by climate change and human activities in recent decades. For the Pearl River, however, long-term variations in the sediment regime, especially in the last decade, remain poorly known. Here we updated knowledge of the temporal trends in the sediment regime of the Pearl River at annual, seasonal and monthly time scales from the 1950s to 2020. Results show that the annual sediment load and suspended sediment concentration (SSC) exhibited drastically decreased, regardless of water discharge. Compared with previous studies, we also found that sediment load and SSC reached a conspicuous peak in the 1980s, and showed a significant decline starting in the 2000s and 1990s, respectively. In the last decade, however, water discharge and sediment load showed slightly increasing trends. At the seasonal scale, the wet-season water discharge displays a decreasing trend, while the dry-season water discharge is increasing. At the monthly scale, the flood seasons in the North and East Rivers typically occur one month earlier than that in the West River due to the different precipitation regimes. Precipitation was responsible for the long-term change of discharge, while human activities (e.g. dam construction and land use change) exerted different effects on the variations in sediment load among different periods. Changes in the sediment regime have exerted substantial influences on downstream channel morphology and saltwater intrusion in the Greater Bay Area. Our study proposes a watershed-based solution, and provides scientific guidelines for the sustainable development of the Greater Bay Area. %B Frontiers in Marine Science %V 9 %G eng %U https://www.frontiersin.org/articles/10.3389/fmars.2022.983517 %0 Journal Article %J Geophysical Research Letters %D 2022 %T Modeling the Dynamics of Salt Marsh Development in Coastal Land Reclamation %A Xu, Yiyang %A Kalra, Tarandeep S. %A Ganju, Neil K. %A Fagherazzi, Sergio %K COAWST %K expectance of marsh coverage %K land reclamation %K marsh restoration %K phases of marsh development %K vegetation dynamics %X The valuable ecosystem services of salt marshes are spurring marsh restoration projects around the world. However, it is difficult to determine the final vegetated area based on physical drivers. Herein, we use a 3D fully coupled vegetation-hydrodynamic-morphological modeling system to simulate the final vegetation cover and the timescale to reach it under various forcing conditions. Marsh development in our simulations can be divided in three distinctive phases: A preparation phase characterized by sediment accumulation in the absence of vegetation, an encroachment phase in which the vegetated area grows, and an adjustment phase in which the vegetated area remains relatively constant while marsh accretes vertically to compensate for sea level rise. Sediment concentration, settling velocity, sea level rise, and tidal range each comparably affect equilibrium coverage and timescale in different ways. Our simulations show that the Unvegetated-Vegetated Ratio also relates to sediment budget in marsh development under most conditions. %B Geophysical Research Letters %V 49 %P e2021GL095559 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1029/2021GL095559 %R 10.1029/2021GL095559 %0 Journal Article %J Sedimentology %D 2022 %T A novel approach to discriminate sedimentary characteristics of deltaic tidal flats with terrestrial laser scanner: Results from a case study %A Wang, Jie %A Dai, Zhijun %A Fagherazzi, Sergio %A Long, Chuqi %K Grain-size distribution %K inversion %K sediments %K terrestrial laser scanner %K tidal flats %X Sediments in deltaic tidal flats regulate physical and chemical processes. Grain-size distribution plays an important role in determining sediment dynamics and substrate properties. However, it is challenging to quantify large-scale depositional environments in intertidal flats, due to time-consuming grain-size analyses and sparse sedimentary information extracted from scattered sediment samples. In this study, a novel terrestrial laser scanner (TLS) based method was developed to characterize the substrate of an intertidal flat. Surface sediment samples in the Nanhui flats in the Yangtze Delta, China, and the corresponding waveform amplitudes of TLS echoes at fixed sampling sites were collected for a total of 22 months. A negative logarithmic relationship was found between the sediment sand fraction, average grain size, D50, and corrected waveform amplitude of TLS echo in different hydro-meteorological conditions. The mean of average grain size of five sediment sampling sites along a transect was 58.78 μm when measured by traditional grain-size analysis, and 49.48 μm when calculated with the proposed logarithmic equation. The mean error at each site was up to 21.77%. The mean error for the sand and silt fraction at each location was as high as 27.28% and 21.75%, respectively. The spatial distribution pattern of TLS-based average grain size in the entire study area was consistent with the measured pattern with a Root Mean Square Error of 13.83 μm. These errors could be caused by the accuracy of the TLS waveform amplitude correction and by limits of the method in recognizing different substrates. The effects produced by the presence of microphytobenthos (for example, cyanobacterial mats or diatom biofilms) or bedforms have not been investigated and may have affected the results. The TLS-based grain-size measurements can rapidly and effectively discriminate sediment characteristics, thus avoiding traditional time-consuming measurements. It is expected that the TLS-based method proposed here will have wide applications in shoreline studies, especially in inaccessible tidal flats. %B Sedimentology %V 69 %P 1626–1648 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1111/sed.12970 %R 10.1111/sed.12970 %0 Journal Article %J Remote Sensing %D 2022 %T Quantifying the Importance of Ice-Rafted Debris to Salt Marsh Sedimentation Using High Resolution UAS Imagery %A Stopak, Sarah %A Nordio, Giovanna %A Fagherazzi, Sergio %K pixel-based classification %K salt marshes %K sediment transport %K storms %X Salt marshes are vulnerable to sea-level rise, sediment deficits, and storm impacts. To remain vertically resilient, salt marshes must accrete sediment at rates greater or equal to sea-level rise. Ice-rafted debris (IRD), sediment that has been moved and deposited from ice sheets, is one of many processes that contribute to salt marsh sediment accretion in northern latitudes. On 4 January 2018, a winter storm caused major ice mobilization in the Plum Island Estuary (PIE), Massachusetts, USA, which led to large deposits of ice-rafted sediment. We aimed to quantify the volume and mass of deposited sediment, and evaluate the significance of IRD to sediment supply in Plum Island using pixel-based land-cover classification of aerial imagery collected by an Unmanned Aircraft System (UAS) and a Digital Elevation Model. Field measurements of patch thickness, and the area of IRD determined from the classification were used to estimate annual sediment accretion from IRD. Results show that IRD deposits are localized in three areas, and estimates show that IRD contributes an annual sediment accretion rate of 0.57 ± 0.14 mm/y to the study site. New England salt marsh accretion rates typically vary between 2–10 mm/y, and the average PIE sediment accretion rate is 2.5–2.7 mm/y. Therefore, this event contributed on average 20% of the annual volume of material accreted by salt marshes, although locally the deposit thickness was 8–14 times the annual accretion rate. We show that pixel-based classification can be a useful tool for identifying sediment deposits from remote sensing. Additionally, we suggest that IRD has the potential to bring a significant supply of sediment to salt marshes in northern latitudes and contribute to sediment accretion. As remotely sensed aerial imagery from UASs becomes more readily available, this method can be used to efficiently identify and quantify deposited sediment. %B Remote Sensing %V 14 %P 5499 %G eng %U https://www.mdpi.com/2072-4292/14/21/5499 %R 10.3390/rs14215499 %0 Journal Article %J Journal of Hydrology %D 2022 %T Salinity increases with water table elevation at the boundary between salt marsh and forest %A Nordio, Giovanna %A Fagherazzi, Sergio %X The migration of salt marshes into forests along coastal regions is nowadays well documented. Sea level rise and storms threaten coastal forests by increasing groundwater levels and salinity. Salinization is the main cause of forest conversion to salt marsh in North America. In this paper we study groundwater levels and salinity in two wells installed at the border between forest and salt marsh in the lower Delmarva peninsula, USA. The upper well is located in the regenerative forest, where recruitment is still possible, while the lower well is located in the persistent forest, where only mature trees survive. Groundwater in the upper well is fresh at the root depth, while in the lower well the mean salinity is 8 ppt. Our data suggest that rainfall has an instantaneous effect on salinity and groundwater levels, but it does not affect salinity and groundwater levels on longer periods (weeks to months). Groundwater levels and salinity reflect the hydraulic gradient toward the marsh (a proxy for outgoing water fluxes), the uphill hydraulic gradient (a proxy for incoming water fluxes) and temperature (a proxy for evapotranspiration). Salinity increases when groundwater levels are high. To explain this result, we put forward the hypothesis that a high water table favors the flux of surficial, fresh water to the marsh, and loss of freshwater by evapotranspiration. These losses are likely replenished by saltier water moving at depth. %B Journal of Hydrology %V 608 %P 127576 %G eng %U https://www.sciencedirect.com/science/article/pii/S0022169422001512 %R 10.1016/j.jhydrol.2022.127576 %0 Journal Article %J Journal of Geophysical Research: Oceans %D 2022 %T Storm Surge and Tidal Dissipation in Deltaic Wetlands Bordering a Main Channel %A Nordio, Giovanna %A Fagherazzi, Sergio %K Energy attenuation %K storm surge %K Tide %K Wavelet transform analysis %K wetland %X Deltas are complex systems where tidal and riverine signals interact with each other. In river-dominated deltas, where river discharge is sufficiently high, tidal amplitude is attenuated and distorted. Here we use wavelet analysis to examine the water level signal in stations located in wetlands adjacent to the main river outlet in the Wax Lake system, part of the Mississippi River Delta in Louisiana, USA. We study the signal attenuation in lateral wetlands at different frequency bands, following the propagation of the water level signal from the Gulf of Mexico to the innermost stations. During high river discharge, the astronomical tide measured inside the wetlands is reduced of 90%–98% in comparison to the tide in Atchafalaya Bay. Storm surge events, largely occurring at lower temporal frequencies, propagate conserving their energy once the signal enters the delta mouth. The river discharge signal, mostly present at frequencies lower than 1.59 μHz, is felt depending on river discharge conditions and the station position within the wetlands. Our results suggest that lateral wetlands in the Wax Lake system act as a low pass filter, attenuating tidal components but not the low frequency components of storm surges. %B Journal of Geophysical Research: Oceans %V 127 %P e2021JC017655 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1029/2021JC017655 %R 10.1029/2021JC017655 %0 Journal Article %J Advances in Water Resources %D 2022 %T Using rapid repeat SAR interferometry to improve hydrodynamic models of flood propagation in coastal wetlands %A Zhang, Xiaohe %A Jones, Cathleen E. %A Oliver-Cabrera, Talib %A Simard, Marc %A Fagherazzi, Sergio %B Advances in Water Resources %V 159 %P 104088 %8 jan %G eng %U https://linkinghub.elsevier.com/retrieve/pii/S0309170821002402 %R 10.1016/j.advwatres.2021.104088 %0 Journal Article %J Journal of Cleaner Production %D 2021 %T Mismatch between watershed effects and local efforts constrains the success of coastal salt marsh vegetation restoration %A Liu, Zezheng %A Fagherazzi, Sergio %A Li, Jin %A Cui, Baoshan %B Journal of Cleaner Production %V 292 %P 126103 %8 apr %G eng %U https://linkinghub.elsevier.com/retrieve/pii/S0959652621003231 %R 10.1016/j.jclepro.2021.126103 %0 Journal Article %J Remote Sensing of Environment %D 2021 %T River body extraction from sentinel-2A/B MSI images based on an adaptive multi-scale region growth method %A Jin, Song %A Liu, Yongxue %A Fagherazzi, Sergio %A Mi, Huan %A Qiao, Gang %A Xu, Wenxuan %A Sun, Chao %A Liu, Yongchao %A Zhao, Bingxue %A Fichot, Cédric G. %B Remote Sensing of Environment %V 255 %P 112297 %8 mar %G eng %U https://linkinghub.elsevier.com/retrieve/pii/S0034425721000158 %R 10.1016/j.rse.2021.112297 %0 Journal Article %J Communications Earth & Environment %D 2021 %T Success of coastal wetlands restoration is driven by sediment availability %A Liu, Zezheng %A Fagherazzi, Sergio %A Cui, Baoshan %X Abstract Shorelines and their ecosystems are endangered by sea-level rise. Nature-based coastal protection is becoming a global strategy to enhance coastal resilience through the cost-effective creation, restoration and sustainable use of coastal wetlands. However, the resilience to sea-level rise of coastal wetlands created under Nature-based Solution has been assessed largely on a regional scale. Here we assess, using a meta-analysis, the difference in accretion, elevation, and sediment deposition rates between natural and restored coastal wetlands across the world. Our results show that restored coastal wetlands can trap more sediment and that the effectiveness of these restoration projects is primarily driven by sediment availability, not by wetland elevation, tidal range, local rates of sea-level rise, and significant wave height. Our results suggest that Nature-based Solutions can mitigate coastal wetland vulnerability to sea-level rise, but are effective only in coastal locations where abundant sediment supply is available. %B Communications Earth & Environment %V 2 %P 44 %8 dec %G eng %U http://www.nature.com/articles/s43247-021-00117-7 %R 10.1038/s43247-021-00117-7 %0 Book Section %B Salt Marshes: Function, Dynamics, and Stresses %D 2021 %T Understanding Marsh Dynamics: Modeling Approaches %A Fagherazzi, Sergio %A Kearney, William %A Mariotti, Giulio %A Leonardi, Nicoletta %A Nardin, William %E FitzGerald, Duncan M. %E Hughes, Zoe J. %X Salt marshes have received considerable scientific attention in recent years due to a combination of factors. Salt marshes host important ecosystems and store large quantities of carbon in their soils (Fagherazzi et al. 2004; Mudd et al. 2009). Currently salt marshes are endangered by accelerated sea-level rise triggered by global warming (Kirwan et al. 2010). A sharp reduction in sediment supply caused by the damming of rivers is also jeopardizing marsh survival along many coasts (Weston 2014). As a result, there is a need to determine the fate of marshlands in different settings in order to inform government and local communities and implement protection strategies. To this end, numerical models are playing an increasingly important role, because they can easily provide future scenarios of marsh conditions under different forcings. However, the evolution of salt marshes as a function of sea-level rise and sediment supply is relatively complex, because of feedbacks among hydrodynamics, sediment transport, and vegetation (Fagherazzi et al. 2012). As a result, marshes are continuously adjusting to a changing environment, in ways often difficult to predict. This intrinsic complexity has generated a flurry of numerical models, each emphasizing a different aspect of salt marsh evolution. It is thus becoming more and more accepted by the scientific community that a comprehensive model of salt marsh evolution is not feasible, given the number and variety of physical and biological processes at play. A detailed approach, based on the description of all possible processes acting at different spatial and temporal scales, has been slowly replaced by a more practical approach, in which separate models are built to address key important processes or to capture specific dynamics. %B Salt Marshes: Function, Dynamics, and Stresses %I Cambridge University Press %C Cambridge %P 278–299 %@ 9781107186286 %G eng %U https://www.cambridge.org/core/books/salt-marshes/understanding-marsh-dynamics/A73B50F7C44E8E7029F450916ECDB72B %R 10.1017/9781316888933.013 %0 Journal Article %J Geophysical Research Letters %D 2020 %T Are Elevation and Open-Water Conversion of Salt Marshes Connected? %A Ganju, Neil K. %A Defne, Zafer %A Fagherazzi, Sergio %X Salt marsh assessments focus on vertical metrics such as accretion or lateral metrics such as open-water conversion, without exploration of how the dimensions are related. We exploited a novel geospatial data set to explore how elevation is related to the unvegetated-vegetated marsh ratio (UVVR), a lateral metric, across individual marsh “units” within four estuarine-marsh systems. We find that elevation scales consistently with the UVVR across systems, with lower elevation units demonstrating more open-water conversion and higher UVVRs. A normalized elevation-UVVR relationship converges across systems near the system-mean elevation and a UVVR of 0.1, a critical threshold identified by prior studies. This indicates that open-water conversion becomes a dominant lateral instability process at a relatively conservative elevation threshold. We then integrate the UVVR and elevation to yield lifespan estimates, which demonstrate that higher elevation marshes are more resilient to internal deterioration, with an order-of-magnitude longer lifespan than predicted for lower elevation marshes. %B Geophysical Research Letters %V 47 %P e2019GL086703 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1029/2019GL086703 %R 10.1029/2019GL086703 %0 Journal Article %J Journal of Environmental Management %D 2020 %T Consumer control and abiotic stresses constrain coastal saltmarsh restoration %A Liu, Zezheng %A Fagherazzi, Sergio %A Ma, Xu %A Xie, Chengjie %A Li, Jin %A Cui, Baoshan %B Journal of Environmental Management %V 274 %P 111110 %8 nov %G eng %U https://linkinghub.elsevier.com/retrieve/pii/S0301479720310379 %R 10.1016/j.jenvman.2020.111110 %0 Journal Article %J Geophysical Research Letters %D 2020 %T Divergence of Sediment Fluxes Triggered by Sea‐Level Rise Will Reshape Coastal Bays %A Zhang, Xiaohe %A Leonardi, Nicoletta %A Donatelli, Carmine %A Fagherazzi, Sergio %B Geophysical Research Letters %V 47 %G eng %U https://onlinelibrary.wiley.com/doi/10.1029/2020GL087862 %R 10.1029/2020GL087862 %0 Journal Article %J Geophysical Research Letters %D 2020 %T Divergence of Sediment Fluxes Triggered by Sea-Level Rise Will Reshape Coastal Bays %A Zhang, Xiaohe %A Leonardi, Nicoletta %A Donatelli, Carmine %A Fagherazzi, Sergio %K bed composition %K numerical modeling %K salt marsh %K sea-level rise %K sediment budget %K tidal flats %X Sediment budget and sediment availability are direct metrics for evaluating the resilience of coastal bays to sea-level rise (SLR). Here we use a high-resolution numerical model of a tidally dominated marsh-lagoon system to explore feedbacks between SLR and sediment dynamics. SLR augments tidal prism and inundation depth, facilitating sediment deposition on the marsh platform. At the same time, our results indicate that SLR enhances ebb-dominated currents and increases sediment resuspension, reducing the sediment-trapping capacity of tidal flats and bays and leading to a negative sediment budget for the entire system. This bimodal distribution of sediments budget trajectories will have a profound impact on the morphology of coastal bays, increasing the difference in elevation between salt marshes and tidal flats and potentially affecting intertidal ecosystems. Our results also clearly indicate that landforms lower with respect to the tidal frame are more affected by SLR than salt marshes. %B Geophysical Research Letters %V 47 %P e2020GL087862 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1029/2020GL087862 %R 10.1029/2020GL087862 %0 Journal Article %J Journal of Geophysical Research: Earth Surface %D 2020 %T Dynamics of Marsh‐Derived Sediments in Lagoon‐Type Estuaries %A Donatelli, Carmine %A Kalra, Tarandeep Singh %A Fagherazzi, Sergio %A Zhang, Xiaohe %A Leonardi, Nicoletta %B Journal of Geophysical Research: Earth Surface %V 125 %8 dec %G eng %U https://onlinelibrary.wiley.com/doi/10.1029/2020JF005751 %R 10.1029/2020JF005751 %0 Journal Article %J Journal of Geophysical Research: Earth Surface %D 2020 %T Dynamics of Marsh-Derived Sediments in Lagoon-Type Estuaries %A Donatelli, Carmine %A Kalra, Tarandeep Singh %A Fagherazzi, Sergio %A Zhang, Xiaohe %A Leonardi, Nicoletta %K Jamaica Bay %K marsh erosion %K sea level rise %K sediment recycling %X Salt marshes are valuable ecosystems that must trap sediments and accrete in order to counteract the deleterious effect of sea level rise. Previous studies have shown that the capacity of marshes to build up vertically depends on both autogenous and exogenous processes including ecogeomorphic feedbacks and sediment supply from in-land and coastal ocean. There have been numerous efforts to quantify the role played by the sediments coming from marsh edge erosion on the resistance of salt marshes to sea level rise. However, the majority of existing studies investigating the interplay between lateral and vertical dynamics use simplified modeling approaches, and they do not consider that marsh retreat can affect the regional-scale hydrodynamics and sediment retention in back-barrier basins. In this study, we evaluated the fate of the sediments originating from marsh lateral loss by using high-resolution numerical model simulations of Jamaica Bay, a small lagoonal estuary located in New York City. Our findings show that up to 42% of the sediment released during marsh edge erosion deposits on the shallow areas of the basin and over the vegetated marsh platforms, contributing positively to the sediment budget of the remaining salt marshes. Furthermore, we demonstrate that with the present-day sediment supply from the ocean, the system cannot keep pace with sea level rise even accounting for the sediment liberated in the bay through marsh degradation. Our study highlights the relevance of multiple sediment sources for the maintenance of the marsh complex. %B Journal of Geophysical Research: Earth Surface %V 125 %P e2020JF005751 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1029/2020JF005751 %R 10.1029/2020JF005751 %0 Journal Article %J Science of The Total Environment %D 2020 %T Efficient tidal channel networks alleviate the drought-induced die-off of salt marshes: Implications for coastal restoration and management %A Liu, Zezheng %A Fagherazzi, Sergio %A She, Xiaojun %A Ma, Xu %A Xie, Chengjie %A Cui, Baoshan %B Science of The Total Environment %V 749 %P 141493 %G eng %U https://linkinghub.elsevier.com/retrieve/pii/S0048969720350221 %R 10.1016/j.scitotenv.2020.141493 %0 Journal Article %J Earth Surface Processes and Landforms %D 2020 %T On the morphology of radial sand ridges %A Zhang, Weina %A Zhang, Xiaohe %A Huang, Huiming %A Wang, Yigang %A Fagherazzi, Sergio %B Earth Surface Processes and Landforms %V 45 %P 2613–2630 %8 sep %G eng %U https://onlinelibrary.wiley.com/doi/10.1002/esp.4917 %R 10.1002/esp.4917 %0 Journal Article %J Journal of Geophysical Research: Earth Surface %D 2020 %T Salt Marsh Dynamics in a Period of Accelerated Sea Level Rise %A Fagherazzi, Sergio %A Mariotti, Giulio %A Leonardi, Nicoletta %A Canestrelli, Alberto %A Nardin, William %A Kearney, William S. %B Journal of Geophysical Research: Earth Surface %V 125 %8 aug %G eng %U https://onlinelibrary.wiley.com/doi/10.1029/2019JF005200 %R 10.1029/2019JF005200 %0 Journal Article %J Geophysical Research Letters %D 2020 %T Tropical Cyclones Significantly Alleviate Mega‐Deltaic Erosion Induced by High Riverine Flow %A Wang, Jie %A Dai, Zhijun %A Mei, Xuefei %A Fagherazzi, Sergio %B Geophysical Research Letters %V 47 %8 oct %G eng %U https://onlinelibrary.wiley.com/doi/10.1029/2020GL089065 %R 10.1029/2020GL089065 %0 Journal Article %J Geophysical Research Letters %D 2020 %T Tropical Cyclones Significantly Alleviate Mega-Deltaic Erosion Induced by High Riverine Flow %A Wang, Jie %A Dai, Zhijun %A Mei, Xuefei %A Fagherazzi, Sergio %K Changjiang Delta %K deltaic morphodynamics %K high runoff %K sediment budget of deltas %K typhoon events %X The drastic decline in sediment discharge experienced by large rivers in recent years might trigger erosion thus increasing the vulnerability of their extensive deltas. However, scarce information is available on the erosion patterns in mega-deltas and associated physical drivers. Here a series of bathymetries in the South Passage, Changjiang Delta, were analyzed to identify morphodynamic variations during high riverine flow and tropical cyclones (TCs). Results indicate that high river flow during flood season triggers large-scale net erosion along the inner estuary, generating elongated erosion-deposition patches. Erosion magnitude gradually weakens moving seaward with few localized bottom variations in the offshore area. TCs transport sediment landward and are accompanied by an overall weak erosion, with a less organized spatial pattern of erosion-deposition. TCs can therefore significantly alleviate erosion, reducing the sediment loss induced by riverine flows by over 50%. These results highlight the role of TCs on the sediment dynamics of mega-deltas. %B Geophysical Research Letters %V 47 %P e2020GL089065 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1029/2020GL089065 %R 10.1029/2020GL089065 %0 Journal Article %J Advances in Water Resources %D 2019 %T Fate of cohesive sediments in a marsh-dominated estuary %A Zhang, Xiaohe %A Leonardi, Nicoletta %A Donatelli, Carmine %A Fagherazzi, Sergio %B Advances in Water Resources %V 125 %P 32–40 %8 mar %G eng %U https://linkinghub.elsevier.com/retrieve/pii/S0309170818305566 %R 10.1016/j.advwatres.2019.01.003 %0 Journal Article %J PLOS ONE %D 2019 %T Sea-level rise and storm surges structure coastal forests into persistence and regeneration niches %A Kearney, William S. %A Fernandes, Arnold %A Fagherazzi, Sergio %E Magar, Vanesa %B PLOS ONE %V 14 %P e0215977 %8 may %G eng %U https://dx.plos.org/10.1371/journal.pone.0215977 %R 10.1371/journal.pone.0215977 %0 Journal Article %J Journal of Geophysical Research: Biogeosciences %D 2018 %T Declining Radial Growth Response of Coastal Forests to Hurricanes and Nor'easters %A Fernandes, Arnold %A Rollinson, Christine R. %A Kearney, William S. %A Dietze, Michael C. %A Fagherazzi, Sergio %K coastal vegetation %K floods %K LTER %K storm surge %K tree ring %X The Mid-Atlantic coastal forests in Virginia are stressed by episodic disturbance from hurricanes and nor'easters. Using annual tree ring data, we adopt a dendroclimatic and statistical modeling approach to understand the response and resilience of a coastal pine forest to extreme storm events, over the past few decades. Results indicate that radial growth of trees in the study area is influenced by age, regional climate trends, and individual tree effects but dominated periodically by growth disturbance due to storms. We evaluated seven local extreme storm events to understand the effect of nor'easters and hurricanes on radial growth. A general decline in radial growth was observed in the year of the extreme storm and 3 years following it, after which the radial growth started recovering. The decline in radial growth showed a statistically significant correlation with the magnitude of the extreme storm (storm surge height and wind speed). This study contributes to understanding declining tree growth response and resilience of coastal forests to past disturbances. Given the potential increase in hurricanes and storm surge severity in the region, this can help predict vegetation response patterns to similar disturbances in the future. %B Journal of Geophysical Research: Biogeosciences %V 123 %P 832–849 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1002/2017JG004125 %R 10.1002/2017JG004125 %0 Journal Article %J Geophysical Research Letters %D 2018 %T Intense Storms Increase the Stability of Tidal Bays %A Castagno, Katherine A. %A Jiménez‐Robles, Alfonso M. %A Donnelly, Jeffrey P. %A Wiberg, Patricia L. %A Fenster, Michael S. %A Fagherazzi, Sergio %B Geophysical Research Letters %V 45 %P 5491–5500 %8 jun %G eng %U https://onlinelibrary.wiley.com/doi/10.1029/2018GL078208 %R 10.1029/2018GL078208 %0 Journal Article %J Limnology and Oceanography: Methods %D 2017 %T Stage-discharge relationship in tidal channels %A Kearney, William S. %A Mariotti, Giulio %A Deegan, Linda A. %A Fagherazzi, Sergio %X Long-term records of the flow of water through tidal channels are essential to constrain the budgets of sediments and biogeochemical compounds in salt marshes. Statistical models which relate discharge to water level allow the estimation of such records from more easily obtained records of water stage in the channel. Here, we compare four different types of stage-discharge models, each of which captures different characteristics of the stage-discharge relationship. We estimate and validate each of these models on a 2-month long time series of stage and discharge obtained with an acoustic Doppler current profiler in a salt marsh channel. We find that the best performance is obtained by models that account for the nonlinear and time-varying nature of the stage-discharge relationship. Good performance can also be obtained from a simplified version of these models, which captures nonlinearity and nonstationarity without the complexity of the fully nonlinear or time-varying models. %B Limnology and Oceanography: Methods %V 15 %P 394–407 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1002/lom3.10168 %R 10.1002/lom3.10168