Kevin D Kroeger, PhD
Kevin Kroeger has studied coastal ecosystems since 1990, with focus on a range of topics including fluxes and biogeochemistry of nitrogen in groundwater discharge to estuaries and wetlands, estuarine water quality, and carbon and greenhouse gas cycling and fluxes in coastal wetlands.
Kroeger is lead of the Biogeochemical Processes group at Woods Hole Coastal and Marine Science Center, and lead of a new project titled: Biogeochemical Drivers of Wetland Persistence and Feedbacks on Coastal Hazards The objectives of this Project are to provide guidance to federal (National Park Service, Fish & Wildlife Service, Army Corp of Engineers), state, local and private land owners and managers regarding stability and persistence of coastal wetlands under a range of hydrological management conditions and changing environmental conditions. Tidal wetlands provide critical services to society, including protection of infrastructure from coastal hazards, and habitat provision for economically important species. A large fraction of U.S. tidal wetlands, however, has been lost or degraded during recent centuries due to human actions, largely related to development and utilization of coastal lands. Feedbacks and interactions among natural and anthropogenic drivers have altered the stability and persistence of coastal wetlands. Decisions regarding hydrological management can alter the balance of organic matter production, retention and preservation, and thus management actions can either promote wetland persistence and resilience, or cause catastrophic loss of elevation, putting coastal infrastructure at increased risk of flooding or storm damage. This project impacts wetland management decisions. The contiguous U.S. has close to 2 million hectares of estuarine and marine wetlands. Nearly all of that area is under some level of management, with the federal government being the largest single manager. Land managers at FWS and NPS, and flood managers at ACOE, must make decisions regarding whether to spend substantial funds to maintain, repair and enhance water control structures under increasing rates of sea level change, or alternatively whether to reduce or remove hydrological management, to restore managed wetlands to more natural hydrology and enhance the capability of wetlands to build elevation over time, and to migrate landward. Society needs guidance and predictions regarding the result of those decisions for continued elevation gain, migration, and ongoing persistence of the wetlands.
Professional Experience
Present: Research Chemist, USGS Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA
2004-2006: Mendenhall Fellow, US Geological Survey Geologic Division, St Petersburg, FL
2003-2004: Postdoctoral Scholar, Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA
1997-2003: Research Fellow and Teaching Fellow, Bos
Education and Certifications
PhD Boston University Marine Program (Biogeochemistry)
M.S. University of Connecticut (Marine Science)
B.A. University of Tennessee (Ecology)
Affiliations and Memberships*
Contributing Author: 2nd State of the Carbon Cycle Report (SOCCR-2), Chapter 15 Tidal Wetlands and Estuaries
Lead, USGS Woods Hole Coastal Biogeochemical Processes Project
Participant, 2017 EPA AFOL
Science and Products
Continuous Monitoring Data From Herring River Wetlands Cape Cod, Massachusetts, 2015-Jan2020
Continuous Monitoring Data From Great Barnstable Marsh on Cape Cod, Massachusetts, 2017-19
Tidal marsh biomass field plot and remote sensing datasets for six regions in the conterminous United States (ver. 2.0, June 2020)
Continuous monitoring data from natural and restored salt marshes on Cape Cod, Massachusetts, 2016-17
Time-series of biogeochemical and flow data from a tidal salt-marsh creek, Sage Lot Pond, Waquoit Bay, Massachusetts, 2012-2016 (ver. 2.0, July 2023)
Geochemical data supporting analysis of geochemical conditions and nitrogen transport in nearshore groundwater and the subterranean estuary at a Cape Cod embayment, East Falmouth, Massachusetts
Collection, analysis, and age-dating of sediment cores from salt marshes on the south shore of Cape Cod, Massachusetts, from 2013 through 2014
Coastal Groundwater Chemical Data from the North and South Shores of Long Island, New York
Continuous and optimized 3-arcsecond elevation model for United States east and west coasts
Data compilation of soil respiration, moisture, and temperature measurements from global warming experiments from 1994-2014
Detection and characterization of coastal tidal wetland change in the northeastern US using Landsat time series
Estimating the aboveground biomass and carbon stocks of tall shrubs in a prerestoration degraded salt marsh
Oxygen-controlled recirculating seepage meter reveals extent of nitrogen transformation in discharging coastal groundwater at the aquifer–estuary interface
Assessment of water quality and discharge in the Herring River, Wellfleet, Massachusetts, November 2015 to September 2017
Pore water exchange-driven inorganic carbon export from intertidal salt marshes
Plant biomass and rates of carbon dioxide uptake are enhanced by successful restoration of tidal connectivity in salt marshes
An important biogeochemical link between organic and inorganic carbon cycling: Effects of organic alkalinity on carbonate chemistry in coastal waters influenced by intertidal salt marshes
Tidal wetland gross primary production across the continental United States, 2000–2019
Phytoplankton community structure response to groundwater-borne nutrients in the inland bays, Delaware
Water salinity and inundation control soil carbon decomposition during salt marsh restoration: An incubation experiment
Salt marsh ecosystem restructuring enhances elevation resilience and carbon storage during accelerating relative sea-level rise
Uncertainty in United States coastal wetland greenhouse gas inventorying
Science and Products
- Science
- Data
Filter Total Items: 22
Continuous Monitoring Data From Herring River Wetlands Cape Cod, Massachusetts, 2015-Jan2020
The Herring River estuary (Wellfleet, Cape Cod, Massachusetts) has been tidally restricted for over a century by a dike constructed near the mouth of the river. Behind the dike, the tidal restriction has caused the conversion of salt marsh wetlands to various other ecosystems including impounded freshwater marshes, flooded shrub land, drained forested upland, and wetlands dominated by Phragmites aContinuous Monitoring Data From Great Barnstable Marsh on Cape Cod, Massachusetts, 2017-19
Salt marshes are environmental ecosystems that contribute to coastal landscape resiliency to storms and rising sea level. Ninety percent of mid-Atlantic and New England salt marshes have been impacted by parallel grid ditching that began in the 1920s–40s to control mosquito populations and to provide employment opportunities during the Great Depression (James-Pirri and others, 2009; Kennish, 2001)Tidal marsh biomass field plot and remote sensing datasets for six regions in the conterminous United States (ver. 2.0, June 2020)
Remote sensing based maps of tidal marshes, both of their extents and carbon stocks, have the potential to play a key role in conducting greenhouse gas inventories and implementing climate mitigation policies. Our objective was to generate a single remote sensing model of tidal marsh aboveground biomass and carbon that represents nationally diverse tidal marshes within the conterminous United StatContinuous monitoring data from natural and restored salt marshes on Cape Cod, Massachusetts, 2016-17
Continuous monitoring data reported are a portion of data from a larger study investigating changes in soil properties, carbon accumulation, and greenhouse gas fluxes in four recently restored salt marsh sites and nearby natural salt marshes. For several decades, local towns, conservation groups, and government organizations have worked to identify, replace, repair, and enlarge culverts to restoreTime-series of biogeochemical and flow data from a tidal salt-marsh creek, Sage Lot Pond, Waquoit Bay, Massachusetts, 2012-2016 (ver. 2.0, July 2023)
Extended time-series sensor data were collected between 2012 and 2016 in surface water of a tidal salt-marsh creek on Cape Cod, Massachusetts. The objective of this field study was to measure water chemical characteristics and flows, as part of a study to quantify lateral fluxes of dissolved carbon species between the salt marsh and estuary. Data consist of in-situ measurements including: salinityGeochemical data supporting analysis of geochemical conditions and nitrogen transport in nearshore groundwater and the subterranean estuary at a Cape Cod embayment, East Falmouth, Massachusetts
This data release provides analytical and other data in support of an analysis of nitrogen transport and transformation in groundwater and in a subterranean estuary in the Eel River and onshore locations on the Seacoast Shores peninsula, Falmouth, Massachusetts. The analysis is described in U.S. Geological Survey Scientific Investigations Report 2018-5095 by Colman and others (2018). This data relCollection, analysis, and age-dating of sediment cores from salt marshes on the south shore of Cape Cod, Massachusetts, from 2013 through 2014
The accretion history of fringing salt marshes located on the south shore of Cape Cod is reconstructed from sediment cores collected in low and high marsh vegetation zones. These marshes are micro-tidal, with a mean tidal range of 0.442 m. Their location within protected embayments and the absence of large rivers results in minimal sediment supply and a dominance of organic matter contributions toCoastal Groundwater Chemical Data from the North and South Shores of Long Island, New York
Groundwater data were collected in the spring and fall of 2008 from three sites representing different geological settings and biogeochemical conditions within the surficial glacial aquifer of Long Island, NY. Investigations were designed to examine the extent to which average vadose zone thickness in contributing watersheds controlled biogeochemical conditions and processes, including dissolved oContinuous and optimized 3-arcsecond elevation model for United States east and west coasts
Investigations of coastal change and coastal resources often require continuous elevation profiles from the seafloor to coastal terrestrial landscapes. Differences in elevation data collection in the terrestrial and marine environments result in separate elevation products that may not share a vertical datum. This data release contains the compilation of multiple elevation products into a continuoData compilation of soil respiration, moisture, and temperature measurements from global warming experiments from 1994-2014
This dataset is the largest global dataset to date of soil respiration, moisture, and temperature measurements, totaling >3800 observations representing 27 temperature manipulation studies, spanning nine biomes and nearly two decades of warming experiments. Data for this study were obtained from a combination of unpublished data and published literature values. We find that although warming increa - Multimedia
- Publications
Filter Total Items: 63
Detection and characterization of coastal tidal wetland change in the northeastern US using Landsat time series
Coastal tidal wetlands are highly altered ecosystems exposed to substantial risk due to widespread and frequent land-use change coupled with sea-level rise, leading to disrupted hydrologic and ecologic functions and ultimately, significant reduction in climate resiliency. Knowing where and when the changes have occurred, and the nature of those changes, is important for coastal communities and natAuthorsXiucheng Yang, Zhe Zhu, Shirley Qiu, Kevin D. Kroeger, Zhiliang Zhu, Scott CovingtonEstimating the aboveground biomass and carbon stocks of tall shrubs in a prerestoration degraded salt marsh
Wetlands play a vital role in Earth's carbon cycle and provide important ecosystem services. Their ability to perform their roles can be compromised by human activities that destroy or impair their functioning. The restoration of degraded wetlands may allow carbon cycle functioning, as well as other services, to be recovered. Predicting the potential outcomes from any restoration project requiresAuthorsJacqualyn Fouse, Meagan J. Eagle, Kevin D. Kroeger, Timothy P. SmithOxygen-controlled recirculating seepage meter reveals extent of nitrogen transformation in discharging coastal groundwater at the aquifer–estuary interface
Nutrient loads delivered to estuaries via submarine groundwater discharge (SGD) play an important role in the nitrogen (N) budget and eutrophication status. However, accurate and reliable quantification of the chemical flux across the final decimeters and centimeters at the sediment–estuary interface remains a challenge, because there is significant potential for biogeochemical alteration due to cAuthorsThomas W. Brooks, Kevin D. Kroeger, Holly A. Michael, Joanna K. YorkAssessment of water quality and discharge in the Herring River, Wellfleet, Massachusetts, November 2015 to September 2017
The U.S. Geological Survey, Cape Cod National Seashore of the National Park Service, and Friends of Herring River cooperated from 2015 to 2017 to assess nutrient concentrations and fluxes across the ocean-estuary boundary at a dike on the Herring River in Wellfleet, Massachusetts. The purpose of this assessment was to characterize environmental conditions prior to a future removal of the dike, whiAuthorsThomas G. Huntington, Alana B. Spaetzel, John A. Colman, Kevin D. Kroeger, Robert T. BradleyPore water exchange-driven inorganic carbon export from intertidal salt marshes
Respiration in intertidal salt marshes generates dissolved inorganic carbon (DIC) that is exported to the coastal ocean by tidal exchange with the marsh platform. Understanding the link between physical drivers of water exchange and chemical flux is a key to constraining coastal wetland contributions to regional carbon budgets. The spatial and temporal (seasonal, annual) variability of marsh poreAuthorsJoseph Tamborski, Meagan J. Eagle, Barret L. Kurylyk, Kevin D. Kroeger, Zhaoihui Wang, Paul Henderson, Matthew CharettePlant biomass and rates of carbon dioxide uptake are enhanced by successful restoration of tidal connectivity in salt marshes
Salt marshes, due to their capability to bury soil carbon (C), are potentially important regional C sinks. Efforts to restore tidal flow to former salt marshes have increased in recent decades in New England (USA), as well as in some other parts of the world. In this study, we investigated plant biomass and carbon dioxide (CO2) fluxes at four sites where restoration of tidal flow occurred five toAuthorsFanning Wang, Meagan J. Eagle, Kevin D. Kroeger, Amanda C. Spivak, Jianwu TangAn important biogeochemical link between organic and inorganic carbon cycling: Effects of organic alkalinity on carbonate chemistry in coastal waters influenced by intertidal salt marshes
Organic acid charge groups in dissolved organic carbon (DOC) contribute to total alkalinity (TA), i.e. organic alkalinity (OrgAlk). Its effect is often ignored or treated as a calculation uncertainty in many aquatic CO2 studies. This study evaluated the variability, sources, and characteristics of OrgAlk in estuarine waters exchanged tidally with a groundwater-influenced salt marsh in the northeasAuthorsShuzhen Song, Zhaohui Aleck Wang, Meagan Gonneea Eagle, Kevin D. Kroeger, Sophie N. Chu, Daoji Li, Haorui LiangTidal wetland gross primary production across the continental United States, 2000–2019
We mapped tidal wetland gross primary production (GPP) with unprecedented detail for multiple wetland types across the continental United States (CONUS) at 16‐day intervals for the years 2000–2019. To accomplish this task, we developed the spatially explicit Blue Carbon (BC) model, which combined tidal wetland cover and field‐based eddy covariance tower data into a single Bayesian framework, and uAuthorsR.A. Feagin, I. Forbrich, T. P. Huff, J.G. Barr, J. Ruiz-Plancarte, J.D. Fuentes, R.G. Najjar, R. Vargas, A. Vazquez Lule, L. Windham-Myers, Kevin D. Kroeger, E. J. Ward, G. W. Moore, M. Leclerc, K. W. Krauss, C.L. Stagg, M. Alber, S. H. Knox, K. V. R. Schafer, T.S. Bianchi, J. A. Hutchings, H. Nahrawi, A. Noormets, B. Mitra, A. Jaimes, A.L. Hinson, Brian A. Bergamaschi, J.S. King, G. MiaoPhytoplankton community structure response to groundwater-borne nutrients in the inland bays, Delaware
To determine the impacts of groundwater-borne nutrients on phytoplankton biomass and community structure, we conducted a series of mesocosm experiments in the Inland Bays of Delaware. Four treatments were tested, including mesocosms coupled directly to submarine groundwater seepage, mesocosms with the addition of pumped submarine groundwater, mesocosms with the addition of phosphate, and control mAuthorsDaniel Torre, Kathryn Coyne, Kevin D. Kroeger, Joanna K. YorkWater salinity and inundation control soil carbon decomposition during salt marsh restoration: An incubation experiment
Coastal wetlands are a significant carbon (C) sink since they store carbon in anoxic soils. This ecosystem service is impacted by hydrologic alteration and management of these coastal habitats. Efforts to restore tidal flow to former salt marshes have increased in recent decades and are generally associated with alteration of water inundation levels and salinity. This study examined the effect ofAuthorsFaming Wang, Kevin D. Kroeger, Meagan Gonneea Eagle, John W. Pohlman, Jianwu TangSalt marsh ecosystem restructuring enhances elevation resilience and carbon storage during accelerating relative sea-level rise
Salt marshes respond to sea-level rise through a series of complex and dynamic bio-physical feedbacks. In this study, we found that sea-level rise triggered salt marsh habitat restructuring, with the associated vegetation changes enhancing salt marsh elevation resilience. A continuous record of marsh elevation relative to sea level that includes reconstruction of high-resolution, sub-decadal, marsAuthorsMeagan Gonneea Eagle, Christopher V. Maio, Kevin D. Kroeger, Andrea D. Hawkes, Jordan Mora, Richard Sullivan, Stephanie Madsen, Richard M. Buzard, Niamh Cahill, Jeffrey P. DonnellyUncertainty in United States coastal wetland greenhouse gas inventorying
Coastal wetlands store carbon dioxide (CO2) and emit CO2 and methane (CH4) making them an important part of greenhouse gas (GHG) inventorying. In the contiguous United States (CONUS), a coastal wetland inventory was recently calculated by combining maps of wetland type and change with soil, biomass, and CH4 flux data from a literature review. We assess uncertainty in this developing carbon monitorAuthorsJames Holmquist, Lisamarie Windham-Myers, Blanca Bernal, Kristin B. Byrd, Steve Crooks, Meagan Gonneea Eagle, Nathan Herold, Sara Knox, Kevin D. Kroeger, John McCombs, J. Patrick Megonigal, Lu Meng, James Morris, Ariana Sutton-Grier, Tiffany Troxler, Donald Weller - News
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government