Estuaries and their surrounding wetlands are coastal transition zones where freshwater rivers meet tidal seawater. As sea levels rise, tidal forces move saltier water farther upstream, extending into freshwater wetland areas. Human changes to the surrounding landscape may amplify the effects of this tidal extension, impacting the resiliency and function of the upper estuarine wetlands. One visible indicator is the rapid conversion of some Southeast and mid-Atlantic tidal freshwater forested wetlands to ‘Ghost Forests’ in which trees die from increases in salinity. Because data on the complex causes and impacts of tidal extension are limited, this project takes an integrated, large-scale approach to research and monitoring to expand our ability to model these processes and apply them to other coastal areas along the Atlantic Coast, Gulf Coast, and internationally. Results of this effort will provide critical data to guide future decisions regarding the fate of carbon, water quality, coastal resilience, wildlife and fisheries, and effective allocation of taxpayer dollars for ecosystem restoration.
Statement of Problem: Throughout the southeastern United States, tidal freshwater forested wetlands (TFFW) found along the upper tidal estuary (where freshwater watersheds and estuaries meet), are converting to ‘Ghost Forests’ (dead trees) and then to oligohaline (low salinity) marsh. Nontidal floodplains are also converting into TFFW as tides extend farther upstream along rivers, and little scientific research has been directed toward describing or understanding the effects of this tidal extension.
Conversion is related to both changing sea level and associated salt-water intrusion and to human influences (e.g., land use change, coastal development, construction of dams, river dredging, etc). All these factors affect the resiliency and ecosystem services provided by wetlands of the upper estuary. Watershed inputs to the upper estuary (water, sediment, nutrients) also may determine the response of TFFW through complex interactions between the ecosystem, water, and landscape. Further, TFFW itself influences delivery of watershed sediment to lower tidal estuaries that are targets of restoration projects, making their function critical to ecosystem health.
Why this Research is Important: This project fills a large gap in integrative ecosystem research and monitoring of different coastal areas which vary in land use activity, tidal range, relative sea-level rise, watershed characteristics and changes, and delivery of ecosystem services for taxpayers. A primary outcome thus far has been the value assigned to TFFW in terms of carbon storage, sequestration, and conveyance; adding them to the list of important "blue carbon" wetlands globally.
“Blue Carbon” refers to carbon that is stored in coastal or marine ecosystems. In addition to the monetary value of the ecosystem services, these coastal wetland areas are crucial for protecting the coast from storm surge, mitigating downstream eutrophication (when a water body becomes overly enriched in nutrients), and providing wildlife and fishery habitat. By improving understanding of the processes and services provided by both healthy TFFW and those transitioned to marshes, managers and coastal inhabitants (and taxpayers) will be able to anticipate how past and current changes will affect the ecosystems in the future.
The TFFW transition/conversion phenomenon is not unique to the southeast and mid-Atlantic United States, and expansion of the project enhances our ability to (1) apply this research to other domestic and international coastal areas undergoing similar changes, and (2) add to critical information gaps on carbon sequestration to better understand the role of coastal ecosystems in the cycling of carbon and nutrients).

Objective(s): We hypothesize that ecosystem functions, sediment and nutrient processes, and carbon sequestration vary in predictable ways in different coastal environments as nontidal floodplains convert to TFFW and TFFW convert to marshes. Through extensive data collection over 15 years, we have quantified several processes and changes to sedimentation, nutrient uptake and release, forest condition, and balance of habitat. From analyses of these data we developed an understanding of emergent processes at multiple scales that are critical to future investigation, culminating in predictive models and advancements to ecological theory of coastal wetland change. In order to further expand our focus from TFFW stresses and degradation, our focus moves to the larger scale of the entire upper estuary landscape, guiding a series of new goals and objectives:
- Maintain repeated measurements at existing field sites in order to reach a full 20-year-record of change, while also incorporating new site locations farther inland, upriver, and into non-tidal zones
- Incorporate new studies to determine where sediment is coming from and what potential land use and management practices may influence sedimentation
- Continue documenting how biogeochemical cycles are affected by changes in the watershed and estuary
- Perform comparative carbon studies between regions to determine generality
- Map and describe tidal extension and landward habitat conversion to develop accurate land cover maps of tidal wetland habitat distribution
- Advance dynamic models to predict upper estuarine habitat change, coupled with elevated CO2 experiments simulating environmental stress to support future modeling
- Begin proactive efforts to compare upper estuarine wetlands of the US Atlantic and Gulf Coasts to similarly positioned habitat conditions globally (e.g., Pacific Northwest, Australia, New Zealand)
Methods: We use a combination of complementary field, laboratory, modeling, and remote sensing techniques to achieve our objectives. Changes in vegetation, tidal extent, surface elevation, and microtopography are measured using field data collection. For example, plots of trees and herbaceous vegetation are surveyed over time to document a record of habitat change, while direct measurements of growth records inform contemporary and historic productivity.
Water level and salinity are measured continuously with logging devices. Surfaces of hummocks and hollows are measured annually to assess changes in elevation, accretion, subsidence and general resilience to sea-level rise. More complex methods that involve both field collection and laboratory analyses are required to measure soil biogeochemistry, nutrients, and carbon (C) storage and flux.
We collect and analyze shallow soil cores (up to 1-meter in depth), for total organic carbon and nitrogen, and date them using Pb-210 activity to determine rates of soil C burial. In analyses of deeper cores (up to 6-7 meters depth), macrofossils, pollen, C-14, and carbon and nutrient sequestration are used to develop historic baselines prior to rising sea-level conditions. Further soil and vegetation analyses assess ground carbon stocks, belowground net ecosystem productivity, greenhouse gas production (CO2, CH4, N2O) in soils of hummocks and hollows, and transpirational demand on soils in forests vs. newly converted marsh.
Finally, river channel bathymetry, longitudinal sampling of suspended and bed sediment, and analysis of sediment stable isotopes and metals to determine changes in mineral and organic sediment sources (“sediment fingerprinting”) are used together to determine how channels and floodplains have changed and have impacted sediment transport. We will use remote sensing techniques to gather information on the extent of tidal flooding along upper estuarine reaches in our study areas. Using our data, we will validate remote sensing results and apply it to regional and national mapping efforts, as well as model development. Synthesizing the various data streams is accomplished through development and application of both statistical and dynamic process models to generate new understanding and tools to predict ecosystem change in new coastal areas.
Below are other science projects associated with this project.
New information on chemical and physical characteristics of streams and floodplains across the Chesapeake Bay and Delaware River watersheds
New dataset available on stream and floodplain geometry to inform restoration decisions
The Response of Coastal Wetlands to Sea-level Rise: Understanding how Macroscale Drivers Influence Local Processes and Feedbacks
Type of Wetlands Affect How Much Nitrogen is Removed from the Bay’s Tidal Rivers
Wetlands in the Quaternary
U.S. Geological Survey (USGS) Science Summary—Vegetation traps nutrients and sediment in the flood plain of an urban stream in the Chesapeake Bay watershed
Science Summary—Sediment and Nutrient Trapping in the Flood Plain of Difficult Run, Virginia, and Implications for the Restoration of Chesapeake Bay
Below are data or web applications associated with this project.
Data on soil denitrification potential and physico-chemical characteristics of tidal freshwater forested wetlands in Virginia.
Input data of WRTDS models to determine trends in the sediment loads of Coastal Plain rivers
Predicting landscape effects of Mississippi River diversions on soil organic carbon sequestration
Below are publications associated with this project.
The potential resiliency of a created tidal marsh to sea-level rise
A 3-year in-situ measurement of CO2 efflux in coastal wetlands: Understanding carbon loss through ecosystem respiration and its partitioning
FLUXNET-CH4 synthesis activity: Objectives, observations, and future directions
Sediment trapping and carbon sequestration in floodplains of the lower Atchafalaya Basin, LA: Allochthonous vs. autochthonous carbon sources
Adaptive management assists reintroduction as higher tides threaten an endangered salt marsh plant
The impact of late Holocene land-use change, climate variability, and sea-level rise on carbon storage in tidal freshwater wetlands on the southeastern United States Coastal Plain
Terrestrial wetlands
Moving from generalisations to specificity about mangrove-saltmarsh dynamics
Growth stress response to sea level rise in species with contrasting functional traits: A case study in tidal freshwater forested wetlands
Flooding alters plant-mediated carbon cycling independently of elevated atmospheric CO2 concentrations
The role of the upper tidal estuary in wetland blue carbon storage and flux
Tidal extension and sea-level rise: recommendations for a research agenda
Below are partners associated with this project.
- Overview
Estuaries and their surrounding wetlands are coastal transition zones where freshwater rivers meet tidal seawater. As sea levels rise, tidal forces move saltier water farther upstream, extending into freshwater wetland areas. Human changes to the surrounding landscape may amplify the effects of this tidal extension, impacting the resiliency and function of the upper estuarine wetlands. One visible indicator is the rapid conversion of some Southeast and mid-Atlantic tidal freshwater forested wetlands to ‘Ghost Forests’ in which trees die from increases in salinity. Because data on the complex causes and impacts of tidal extension are limited, this project takes an integrated, large-scale approach to research and monitoring to expand our ability to model these processes and apply them to other coastal areas along the Atlantic Coast, Gulf Coast, and internationally. Results of this effort will provide critical data to guide future decisions regarding the fate of carbon, water quality, coastal resilience, wildlife and fisheries, and effective allocation of taxpayer dollars for ecosystem restoration.
Statement of Problem: Throughout the southeastern United States, tidal freshwater forested wetlands (TFFW) found along the upper tidal estuary (where freshwater watersheds and estuaries meet), are converting to ‘Ghost Forests’ (dead trees) and then to oligohaline (low salinity) marsh. Nontidal floodplains are also converting into TFFW as tides extend farther upstream along rivers, and little scientific research has been directed toward describing or understanding the effects of this tidal extension.
Conversion is related to both changing sea level and associated salt-water intrusion and to human influences (e.g., land use change, coastal development, construction of dams, river dredging, etc). All these factors affect the resiliency and ecosystem services provided by wetlands of the upper estuary. Watershed inputs to the upper estuary (water, sediment, nutrients) also may determine the response of TFFW through complex interactions between the ecosystem, water, and landscape. Further, TFFW itself influences delivery of watershed sediment to lower tidal estuaries that are targets of restoration projects, making their function critical to ecosystem health.
Diagram showing the transition from a) tidal freshwater forested wetland (TFFW) to b) tidal fresh water marsh to c) low-salinity marsh to d) saltmarsh with increasing salinity and the movement of carbon in, out, and through this system. Modified from Figure 1 in (Krauss et al., 2018) Why this Research is Important: This project fills a large gap in integrative ecosystem research and monitoring of different coastal areas which vary in land use activity, tidal range, relative sea-level rise, watershed characteristics and changes, and delivery of ecosystem services for taxpayers. A primary outcome thus far has been the value assigned to TFFW in terms of carbon storage, sequestration, and conveyance; adding them to the list of important "blue carbon" wetlands globally.
“Blue Carbon” refers to carbon that is stored in coastal or marine ecosystems. In addition to the monetary value of the ecosystem services, these coastal wetland areas are crucial for protecting the coast from storm surge, mitigating downstream eutrophication (when a water body becomes overly enriched in nutrients), and providing wildlife and fishery habitat. By improving understanding of the processes and services provided by both healthy TFFW and those transitioned to marshes, managers and coastal inhabitants (and taxpayers) will be able to anticipate how past and current changes will affect the ecosystems in the future.
The TFFW transition/conversion phenomenon is not unique to the southeast and mid-Atlantic United States, and expansion of the project enhances our ability to (1) apply this research to other domestic and international coastal areas undergoing similar changes, and (2) add to critical information gaps on carbon sequestration to better understand the role of coastal ecosystems in the cycling of carbon and nutrients).
Sources/Usage: Some content may have restrictions. Visit Media to see details.A ghost forest in tidal freshwater forested wetlands of the Sampit River, South Carolina.Photo taken June 17, 2015 by Dr. William Conner, Clemson University Objective(s): We hypothesize that ecosystem functions, sediment and nutrient processes, and carbon sequestration vary in predictable ways in different coastal environments as nontidal floodplains convert to TFFW and TFFW convert to marshes. Through extensive data collection over 15 years, we have quantified several processes and changes to sedimentation, nutrient uptake and release, forest condition, and balance of habitat. From analyses of these data we developed an understanding of emergent processes at multiple scales that are critical to future investigation, culminating in predictive models and advancements to ecological theory of coastal wetland change. In order to further expand our focus from TFFW stresses and degradation, our focus moves to the larger scale of the entire upper estuary landscape, guiding a series of new goals and objectives:
- Maintain repeated measurements at existing field sites in order to reach a full 20-year-record of change, while also incorporating new site locations farther inland, upriver, and into non-tidal zones
- Incorporate new studies to determine where sediment is coming from and what potential land use and management practices may influence sedimentation
- Continue documenting how biogeochemical cycles are affected by changes in the watershed and estuary
- Perform comparative carbon studies between regions to determine generality
- Map and describe tidal extension and landward habitat conversion to develop accurate land cover maps of tidal wetland habitat distribution
- Advance dynamic models to predict upper estuarine habitat change, coupled with elevated CO2 experiments simulating environmental stress to support future modeling
- Begin proactive efforts to compare upper estuarine wetlands of the US Atlantic and Gulf Coasts to similarly positioned habitat conditions globally (e.g., Pacific Northwest, Australia, New Zealand)
Methods: We use a combination of complementary field, laboratory, modeling, and remote sensing techniques to achieve our objectives. Changes in vegetation, tidal extent, surface elevation, and microtopography are measured using field data collection. For example, plots of trees and herbaceous vegetation are surveyed over time to document a record of habitat change, while direct measurements of growth records inform contemporary and historic productivity.
Water level and salinity are measured continuously with logging devices. Surfaces of hummocks and hollows are measured annually to assess changes in elevation, accretion, subsidence and general resilience to sea-level rise. More complex methods that involve both field collection and laboratory analyses are required to measure soil biogeochemistry, nutrients, and carbon (C) storage and flux.
We collect and analyze shallow soil cores (up to 1-meter in depth), for total organic carbon and nitrogen, and date them using Pb-210 activity to determine rates of soil C burial. In analyses of deeper cores (up to 6-7 meters depth), macrofossils, pollen, C-14, and carbon and nutrient sequestration are used to develop historic baselines prior to rising sea-level conditions. Further soil and vegetation analyses assess ground carbon stocks, belowground net ecosystem productivity, greenhouse gas production (CO2, CH4, N2O) in soils of hummocks and hollows, and transpirational demand on soils in forests vs. newly converted marsh.
Finally, river channel bathymetry, longitudinal sampling of suspended and bed sediment, and analysis of sediment stable isotopes and metals to determine changes in mineral and organic sediment sources (“sediment fingerprinting”) are used together to determine how channels and floodplains have changed and have impacted sediment transport. We will use remote sensing techniques to gather information on the extent of tidal flooding along upper estuarine reaches in our study areas. Using our data, we will validate remote sensing results and apply it to regional and national mapping efforts, as well as model development. Synthesizing the various data streams is accomplished through development and application of both statistical and dynamic process models to generate new understanding and tools to predict ecosystem change in new coastal areas.
- Science
Below are other science projects associated with this project.
New information on chemical and physical characteristics of streams and floodplains across the Chesapeake Bay and Delaware River watersheds
Issue: Improving stream health is an important outcome of the Chesapeake Bay Program partnership. Stream conditions are important for recreational fisheries, and mitigating the amount of nutrients, sediment, and contaminants delivered to the Bay.New dataset available on stream and floodplain geometry to inform restoration decisions
Issue: The need for stream mapping The physical shape of streams and floodplains can provide information about how water, sediment, and other matter moves through the landscape. Streams can have deep channels (tall streambanks) disconnected from the floodplain or wide shallow channels that easily spill over the banks into the floodplain during high flows. Mapping where streams fall along this...The Response of Coastal Wetlands to Sea-level Rise: Understanding how Macroscale Drivers Influence Local Processes and Feedbacks
The purpose of this work is to advance our understanding of how coastal wetland responses to sea-level rise (SLR) within the conterminous United States are likely to vary as a function of local, regional, and macroscale drivers, including climate. Based on our interactions with managers and decision makers, as well as our knowledge of the current state of the science, we propose to: (a) conduct a...Type of Wetlands Affect How Much Nitrogen is Removed from the Bay’s Tidal Rivers
Issue: Wetlands are important for removing nitrogen from rivers entering the Chesapeake Bay. More information is needed on how much nitrogen wetlands can remove.Wetlands in the Quaternary
Wetlands accumulate organic-rich sediment or peat stratigraphically, making them great archives of past environmental change. Wetlands also act as hydrologic buffers on the landscape and are important to global biogeochemical cycling. This project uses wetland archives from a range of environments to better understand how vegetation, hydrology, and hydroclimate has changed on decadal to multi...U.S. Geological Survey (USGS) Science Summary—Vegetation traps nutrients and sediment in the flood plain of an urban stream in the Chesapeake Bay watershed
Urbanization in the Chesapeake Bay watershed has increased stream discharge, the frequency of flood-plain inundation, and the transport of nutrients (such as nitrogen and phosphorus) and sediment to streams and, ultimately, to the bay. Understanding the effects of the abundance, composition, and location of vegetation on flood-plain functions such as nutrient cycling and sediment trapping can aid...Science Summary—Sediment and Nutrient Trapping in the Flood Plain of Difficult Run, Virginia, and Implications for the Restoration of Chesapeake Bay
As the largest and most productive estuary in North America, Chesapeake Bay is a vital ecological and economic resource. The bay and its tributaries have been degraded in recent decades, however, by excessive inputs of nutrients (nitrogen and phosphorus) and sediment, causing poor water-quality conditions for fish and wildlife. Nitrogen and phosphorus cause algae blooms, fish kills, and poor water... - Data
Below are data or web applications associated with this project.
Data on soil denitrification potential and physico-chemical characteristics of tidal freshwater forested wetlands in Virginia.
Denitrification measurements and ecosystem attributes in hummock-hollow microtopography of tidal freshwater forested wetlands along longitudinal riverine positions (upper, middle, and lower tidal river sites, and nearby upstream nontidal forested floodplains) of the adjoining Pamunkey and Mattaponi Rivers, Virginia.Input data of WRTDS models to determine trends in the sediment loads of Coastal Plain rivers
Input data for WRTDS models to determine changes in sediment loads in Coastal Plain Rivers of the Atlantic Coast, United States.Predicting landscape effects of Mississippi River diversions on soil organic carbon sequestration
It contains supporting data from the wetland morphology modeling to support the analysis on the landscape effects of Mississippi River diversions in the context of sea-level rise on soil organic carbon (SOC) sequestration along coastal Louisiana wetlands. - Publications
Below are publications associated with this project.
Filter Total Items: 56The potential resiliency of a created tidal marsh to sea-level rise
The purpose of this study was to determine the elevation dynamics of a created tidal marsh on the North Carolina coast. Deep rod surface elevation tables (RSET) and feldspar marker horizons (MH) were installed in plots to measure net surface elevation changes and to quantify contributing processes. Twelve total plots were placed on four elevation gradient transects (three transects within the creaAuthorsBrock J. W. Kamrath, Michael R. Burchell, Nicole Cormier, Ken W. Krauss, Darren JohnsonA 3-year in-situ measurement of CO2 efflux in coastal wetlands: Understanding carbon loss through ecosystem respiration and its partitioning
Understanding the link between ecosystem respiration (Reco) and its influential factors is necessary to evaluate the sources of gaseous carbon loss in coastal wetlands. Seablite (Suaeda salsa Pall.) is the main vegetation type pioneering temperate coastal wetlands in northeast China, and is generally an understudied wetland type. To evaluate the influence of environmental factors on Reco, a multi-AuthorsXueyang Yu, Siyuan Ye, Linda Olsson, Mengjie Wei, Ken Krauss, Hans BrixFLUXNET-CH4 synthesis activity: Objectives, observations, and future directions
This paper describes the formation of, and initial results for, a new FLUXNET coordination network for ecosystem-scale methane (CH4) measurements at 60 sites globally, organized by the Global Carbon Project in partnership with other initiatives and regional flux tower networks. The objectives of the effort are presented along with an overview of the coverage of eddy covariance (EC) CH4 flux measurAuthorsSara H. Knox, Robert B. Jackson, Benjamin Poulter, Gavin McNicol, Etienne Fluet-Chouinard, Zhen Zhang, Gustaf Hugelius, Philippe Bousquet, Josep G Canadell, Marielle Saunois, Dario Papale, Housen Chu, Trevor F. Keenan, Dennis Baldocchi, Margaret S. Torn, Ivan Mammarella, Carlo Trotta, Mika Aurela, Gil Bohrer, David I. Campbell, Alessandro Cescatti, Samuel D. Chamberlain, Jiquan Chen, Weinan Chen, Sigrid Dengel, Ankur R. Desai, Eugenie S. Euskirchen, Thomas Friborg, Daniele Gasbarra, Ignacio Goded, Mathias Goeckede, Martin Heimann, Manuel Helbig, Takashi Hirano, David Y. Hollinger, Hiroki Iwata, Minseok Kang, Janina Klatt, Ken Krauss, Lars Kutzbach, Annalea Lohila, Bhaskar Mitra, Timothy H Morin, Mats B. Nilsson, Shuli Niu, Asko Noormets, Walter C. Oechel, Matthias Peichl, Olli Peltola, Michele L. Reba, Andrew D. Richardson, Benjamin R. K. Runkle, Youngryel Ryu, Torsten Sachs, Karina V R Schäfer, Hans Peter Schmid, Narasinha Shurpali, Oliver Sonnentag, Angela C I Tang, Masahito Ueyama, Rodrigo Vargas, Timo Vesala, Eric Ward, Lisamarie Windham-Myers, Georg Wohlfahrt, Donatella ZonaSediment trapping and carbon sequestration in floodplains of the lower Atchafalaya Basin, LA: Allochthonous vs. autochthonous carbon sources
Recent studies suggest that about 2 Pg of organic C is stored on floodplains worldwide. The present study indicates the Atchafalaya River, fifth largest river in the United States in terms of discharge, traps 30 mm/y of sediment on average within its floodplain, which is the highest average non‐episodic rate of fluvial deposition on the U.S. Coastal Plain. We installed sediment sampling stations aAuthorsCliff R. Hupp, Daniel E. Kroes, Gregory B. Noe, Edward R. Schenk, Richard H. DayAdaptive management assists reintroduction as higher tides threaten an endangered salt marsh plant
In theory, extirpated plant species can be reintroduced and managed to restore sustainable populations. However, few reintroduced plants are known to persist for more than a few years. Our adaptive‐management case study illustrates how we restored the endangered hemiparasitic annual plant, Chloropyron maritimum subsp. maritimum (salt marsh bird's beak), to Sweetwater Marsh, San Diego Bay NationalAuthorsGregory B. Noe, Meghan Fellows, Lorraine Parsons, Janelle West, John C. Callaway, Sally Trnka, Mark Wegener, Joy ZedlerThe impact of late Holocene land-use change, climate variability, and sea-level rise on carbon storage in tidal freshwater wetlands on the southeastern United States Coastal Plain
This study examines Holocene impacts of changes in climate, land use, and sea-level rise (SLR) on sediment accretion, carbon accumulation rates (CAR), and vegetation along a transect of tidal freshwater forested wetlands (TFFW) to oligohaline marsh along the Waccamaw River, South Carolina (4 sites) and along the Savannah River, Georgia (4 sites). We use pollen, plant macrofossils, accretion, and CAuthorsMiriam Jones, Christopher E. Bernhardt, K. W. Krauss, Gregory B. NoeTerrestrial wetlands
1. The assessment of terrestrial wetland carbon stocks has improved greatly since the First State of the Carbon Cycle Report (CCSP 2007) because of recent national inventories and the development of a U.S. soils database. Terrestrial wetlands in North America encompass an estimated 2.2 million km2, which constitutes about 37% of the global wetland area, with a soil and vegetation carbon pool of abAuthorsRandall Kolka, Carl Trettin, Wenwu Tang, Ken W. Krauss, Sheel Bansal, Judith Z. Drexler, Kimberly P. Wickland, Rodney A. Chimner, Dianna M. Hogan, Emily J. Pindilli, Brian Benscoter, Brian Tangen, Evan S. Kane, Scott D. Bridgham, Curtis J. RichardsonMoving from generalisations to specificity about mangrove-saltmarsh dynamics
Spatial and temporal variability in factors influencing mangrove establishment and survival affects the distribution of mangrove, particularly near their latitudinal limit, where mangrove expansion into saltmarsh is conspicuous. In this paper the spatial variability in mangrove distribution and variability in factors influencing mangrove establishment and survival during the Quaternary period areAuthorsKerrylee Rogers, Ken W. KraussGrowth stress response to sea level rise in species with contrasting functional traits: A case study in tidal freshwater forested wetlands
With rising sea levels, mortality of glycophytes can be caused by water and nutrient stress under increasing salinity. However, the relative effects of these two stressors may vary by species-specific functional traits. For example, deciduous species, with leaves typically emerging during low salinity periods of the year, may suffer less from water stress than evergreen species. We sampled two wooAuthorsLu Zhai, Ken W. Krauss, Xin Liu, Jamie A. Duberstein, William H. Conner, Donald L. DeAngelis, Leonel d.S.L SternbergFlooding alters plant-mediated carbon cycling independently of elevated atmospheric CO2 concentrations
Plant‐mediated processes determine carbon (C) cycling and storage in many ecosystems; how plant‐associated processes may be altered by climate‐induced changes in environmental drivers is therefore an essential question for understanding global C cycling. In this study, we hypothesize that environmental alterations associated with near‐term climate change can exert strong control on plant‐associateAuthorsScott F. Jones, Camille L. Stagg, Ken W. Krauss, Mark W. HesterThe role of the upper tidal estuary in wetland blue carbon storage and flux
Carbon (C) standing stocks, C mass balance, and soil C burial in tidal freshwater forested wetlands (TFFW) and TFFW transitioning to low‐salinity marshes along the upper estuary are not typically included in “blue carbon” accounting, but may represent a significant C sink. Results from two salinity transects along the tidal Waccamaw and Savannah rivers of the US Atlantic Coast show total C standinAuthorsKen W. Krauss, Gregory B. Noe, Jamie A. Duberstein, William H. Conner, Camille L. Stagg, Nicole Cormier, Miriam C. Jones, Christopher E. Bernhardt, B. Graeme Lockaby, Andrew S. From, Thomas W. Doyle, Richard H. Day, Scott H. Ensign, Katherine N. Pierfelice, Cliff R. Hupp, Alex T. Chow, Julie L. WhitbeckTidal extension and sea-level rise: recommendations for a research agenda
Sea-level rise is pushing freshwater tides upstream into formerly non-tidal rivers. This tidal extension may increase the area of tidal freshwater ecosystems and offset loss of ecosystem functions due to salinization downstream. Without considering how gains in ecosystem functions could offset losses, landscape-scale assessments of ecosystem functions may be biased toward worst-case scenarios of lAuthorsScott H. Ensign, Gregory B. Noe - Partners
Below are partners associated with this project.