Ken Krauss is a Research Ecologist at the USGS Wetland and Aquatic Research Center.
EDUCATION
Ph.D., Biology, University of Louisiana at Lafayette, 2004
M.S., Forestry, Louisiana State University, 1997
B.S., Biology, University of Southwestern Louisiana, 1994
RESEARCH
Ken Krauss' research spans several habitats, from mangroves to tidal freshwater forested wetlands and marshes. His research takes a multi-tiered approach to understanding eco-physiological processes in coastal wetland forests; defining gas exchange between the soil and atmosphere, and among the leaf, tree, and atmosphere. Research has defined thresholds to tidal freshwater forested wetland habitat change in the face of persistent environmental drivers (esp. sea level rise and salinity), defined the potential of forested wetlands to influence water cycling in coastal areas, and has begun to establish the potential of other wetland types to contribute to water conservation, especially under drought and perennial salinization. Krauss also focuses on the vulnerability of coastal swamp forests and mangroves to sea-level rise, and on how science can inform management and restoration activity within the coastal zone.
BACKGROUND
He has been a scientist with the federal government since 1997, first with the USDA Forest Service in Stoneville, Mississippi and, then, in Honolulu, Hawaii, where he studied sedimentation, systematics, regeneration, growth, invasion biology, and ecophysiology of Pacific island forested wetlands in the Federated States of Micronesia and Hawaii. Krauss began working at the USGS National Wetlands Research Center in 2001 (renamed to USGS Wetland and Aquatic Research Center, or WARC, in 2015), where he maintains an expertise in forest ecology and ecophysiology, and serves as one of WARC's climate change scientists focusing on mangroves and tidal freshwater forested wetlands.
2004-present, Research Ecologist, U.S. Geological Survey, Wetland and Aquatic Research Center, Lafayette, Louisiana
2001-2004, Ecologist, U.S. Geological Survey, National Wetlands Research Center, Lafayette, Louisiana
1997-2001, Ecologist, USDA Forest Service, Institute of Pacific Islands Forestry, Honolulu, Hawaii
1996-1997, Ecophysiologist Technician, USDA Forest Service, Center for Bottomland Hardwoods Forestry, Stoneville, Mississippi
1995-1996, Graduate Research Assistant, Louisiana State University, School of Forestry, Wildlife, and Fisheries, Baton Rouge, Louisiana
Science and Products
Summary of wetland carbon and environmental management: Path forward
Carbon fluxes and potential soil accumulation within Greater Everglades cypress and pine forested wetlands
Modeling the impacts of hydrology and management on carbon balance at the Great Dismal Swamp, Virginia and North Carolina, USA
Carbon flux, storage, and wildlife co-benefits in a restoring estuary
Watershed and estuarine controls both influence plant community and tree growth changes in tidal freshwater forested wetlands along two U.S. mid-Atlantic rivers
FLUXNET-CH4: A global, multi-ecosystem database and analysis of methane seasonality from freshwater wetlands
Belowground productivity varies by assessment technique, vegetation type, and nutrient availability in tidal freshwater forested wetlands transitioning to marsh
Substantial hysteresis in emergent temperature sensitivity of global wetland CH4 emissions
Mangrove species’ response to sea-level rise across Pohnpei, Federated States of Micronesia
Does geomorphology determine vulnerability of mangrove coasts to sea-level rise?
Mangroves and people: Impacts and interactions
Surface elevation change evaluation in mangrove forests using a low‐cost, rapid‐scan terrestrial laser scanner
Pre-USGS Publications
Carbon and Water Budgeting Along Upper Estuaries: Developing Linkages to Environmental Change
Assessing Environmental Stress in Mature Mangrove Stands: Linkages to Nutrient Loading
Wetland Carbon Working Group: Improving Methodologies and Estimates of Carbon and Greenhouse Gas Flux in Wetlands
Sea-level Rise Vulnerability of Mangrove Forests in Micronesia and the Pacific
Impacts of coastal and watershed changes on upper estuaries: causes and implications of wetland ecosystem transitions along the US Atlantic and Gulf Coasts
The Impact of Sea-Level Rise on Coral Reef and Mangrove Interactions and the Resulting Coastal Flooding Hazards
Science to Inform the Management of Mangrove Ecosystems Undergoing Sea Level Rise at Ding Darling National Wildlife Refuge, Sanibel Island, Florida
Understanding Impacts of Sea-Level Rise and Land Management on Critical Coastal Marsh Habitat
Assessing the Benefits and Vulnerability of Current and Future Potential Ecosystem Services of the Nisqually River Delta and other Puget Sound Estuaries
Improving Our Ability to Forecast Tidal Marsh Response to Sea Level Rise
Ecology of Greenhouse Gas Emissions from Coastal Wetlands
Evaluating Structural and Surface Elevation Recovery of Restored Mangroves
Above- and belowground biomass production, decomposition, and wetland elevation change in transitional coastal wetland communities exposed to elevated CO2 and sediment deposition: a mesocosm study from 2012 to 2014
Simulated Methane and Nitrous Oxide Emissions under Drought-induced Saltwater Intrusion in Tidal Freshwater Forested Wetlands
Mangrove Elevation and Species' Responses to Sea-level Rise Across Pohnpei, Federated States of Micronesia
Fine root production in tidally influenced freshwater forested wetlands in South Carolina and Georgia, USA (2016-2017)
Soil surface elevation change and vertical accretion data to support the Fruit Farm Creek Mangrove Restoration Project (Rookery Bay National Estuarine Research Reserve, Marco Island, Florida)
Forest structure, regeneration, and soil data to support mangrove forest damage assessment on St. John, U.S. Virgin Islands, from Hurricane Irma (2018-2019)
Modeling soil pore water salinity response to drought in tidal freshwater forested wetlands
Rapid peat development beneath maturing mangrove forests: quantifying ecosystem changes along a 25-year chronosequence of created coastal wetlands
Carbon budget assessment of tidal freshwater forested wetland and oligohaline marsh ecosystems along the Waccamaw and Savannah rivers, U.S.A. (2005-2016)
Water level and soil pore water salinity, temperature, and conductivity data in tidally influenced forested wetlands in South Carolina and Georgia
Sap flow data from a long-hydroperiod forested wetland undergoing salinity intrusion in South Carolina, USA
Forest community biomass and growth in Great Dismal Swamp, Virginia and North Carolina, USA
Science and Products
- Publications
Filter Total Items: 146
Summary of wetland carbon and environmental management: Path forward
Wetlands around the world are under pressure from both anthropogenic sources such as land-use change and accelerating climate change (Erwin, 2009; Moomaw et al., 2018). Storage of carbon resources is a key ecosystem service of wetlands and offer natural solutions to climate change mitigation; policies and management actions could determine the fate of these resources and their contributions to cliCarbon fluxes and potential soil accumulation within Greater Everglades cypress and pine forested wetlands
In forested wetlands, accumulation of organic matter in soil is partly governed by carbon fluxes where photosynthesis, respiration, lateral advection of waterborne carbon, fire-derived carbon emissions, and methanogenesis are balanced by changes in stored carbon. Stored carbon can eventually accumulate as soil over time if net primary productivity exceeds biomass decomposition. For this study, potModeling the impacts of hydrology and management on carbon balance at the Great Dismal Swamp, Virginia and North Carolina, USA
The impact of drainage on the stability of peatland carbon sinks is well known; however, much less is understood regarding the way active management of the water-table affects carbon balance. In this study, we determined the carbon balance in the Great Dismal Swamp, a large, forested peatland in the southeastern USA, which has been drained for over two hundred years and is now being restored throuCarbon flux, storage, and wildlife co-benefits in a restoring estuary
Tidal marsh restorations may result in transitional mudflat habitats depending on hydrological and geomorphological conditions. Compared to tidal marsh, mudflats are thought to have limited value for carbon sequestration, carbon storage, and foraging benefits for salmon. We evaluated greenhouse gas exchange, sediment carbon storage, and invertebrate production at restoration and reference tidal maWatershed and estuarine controls both influence plant community and tree growth changes in tidal freshwater forested wetlands along two U.S. mid-Atlantic rivers
The tidal freshwater zone near the estuarine head-of-tide is potentially sensitive to both sea-level rise and associated salinity increases as well as changing watershed inputs of freshwater and nutrients. We evaluated the vegetation response of tidal freshwater forested wetlands (TFFW) to changes in nontidal river versus estuarine controls along the longitudinal gradient of the Mattaponi and PamuFLUXNET-CH4: A global, multi-ecosystem database and analysis of methane seasonality from freshwater wetlands
Methane (CH4) emissions from natural landscapes constitute roughly half of global CH4 contributions to the atmosphere, yet large uncertainties remain in the absolute magnitude and the seasonality of emission quantities and drivers. Eddy covariance (EC) measurements of CH4 flux are ideal for constraining ecosystem-scale CH4 emissions due to quasi-continuous and high-temporal-resolution CH4 flux meaBelowground productivity varies by assessment technique, vegetation type, and nutrient availability in tidal freshwater forested wetlands transitioning to marsh
Wetlands along upper estuaries are characterized by dynamic transitions between forested and herbaceous communities (marsh) as salinity, hydroperiod, and nutrients change. The importance of belowground net primary productivity (BNPP) associated with fine and coarse root growth also changes but remains the dominant component of overall productivity in these important blue carbon wetlands. AppropriaSubstantial hysteresis in emergent temperature sensitivity of global wetland CH4 emissions
Wetland methane (CH4) emissions (FCH4) are important in global carbon budgets and climate change assessments. Currently, FCH4 projections rely on prescribed static temperature sensitivity that varies among biogeochemical models. Meta-analyses have proposed a consistent FCH4 temperature dependence across spatial scales for use in models; however, site-level studies demonstrate that FCH4 are often cMangrove species’ response to sea-level rise across Pohnpei, Federated States of Micronesia
Mangrove forests are likely vulnerable to accelerating sea-level rise; however, we lack the tools necessary to understand their future resilience. On the Pacific island of Pohnpei, Federated States of Micronesia, mangroves are habitat to endangered species and provide critical ecosystem services that support local communities. We developed a generalizable modeling framework for mangroves that accoDoes geomorphology determine vulnerability of mangrove coasts to sea-level rise?
The greatest climate-based threat to coastlines worldwide is sea-level rise. We tested the hypothesis that tropical coasts fringed by mangroves and receiving high inputs of terrigenous sediment are less vulnerable to sea-level rise than biogenic systems dependent upon peat formation for vertical land development. An analysis of published data spanning a range of geomorphic settings showed that minMangroves and people: Impacts and interactions
Mangroves have long been associated with human populations, as coastal communities rely on the various ecosystem services that mangroves provide. However, human degradation and destruction of mangrove forests is common, despite and because of our reliance on them as valuable ecosystems. Mangrove research and management must elucidate and reconcile these conflicts to maintain mangrove forests and tSurface elevation change evaluation in mangrove forests using a low‐cost, rapid‐scan terrestrial laser scanner
Mangrove forests have adapted to sea level rise (SLR) increases by maintaining their forest floor elevation via belowground root growth and surface sediment deposits. Researchers use surface elevation tables (SETs) to monitor surface elevation change (SEC) in mangrove forests, after which this information is used to assess SLR resiliency or to dictate active forest management for vulnerable systemPre-USGS Publications
Kumara, M.P., L.P. Jayatissa, K.W. Krauss, D.H. Phillips, & M. Huxham. 2010. High mangrove density enhances surface accretion, surface elevation change, and tree survival in coastal areas susceptible to sea-level rise. Oecologia 164: 545-553.Huxham, M., M. Kumara, L. Jayatissa, K.W. Krauss, J. Kairo, J. Langat, M. Mencuccini, M. Skov & B. Kirui. 2010. Intra and inter-specific facilitation in mangroves may increase resilience to climate change threats. Philosophical Transactions of the Royal Society of London B 365: 2127-2135.Krauss, K.W. 2009. Mangrove energetics. Ecology 90: 3588-3589. [book review]Krauss, K.W., C.E. Lovelock, K.L. McKee, L. López-Hoffman, S.M.L. Ewe & W.P. Sousa. 2008. Environmental drivers in mangrove establishment and early development: a review. Aquatic Botany 89: 105-127.Conner, W.H., T.W. Doyle & K.W. Krauss, Eds., 2007. Ecology of Tidal Freshwater Forested Wetlands of the Southeastern United States. Springer. 505 p.Krauss, K.W., J.L. Chambers & D. Creech. 2007. Selection for salt tolerance in tidal freshwater swamp species: advances using baldcypress as a model for restoration. Pages 385-410 in W.H. Conner, T.W. Doyle, K.W. Krauss (eds.), Ecology of Tidal Freshwater Forested Wetlands of the Southeastern United States. Springer. 505 p.Conner W.H., K.W. Krauss & T.W. Doyle. 2007. Ecology of tidal freshwater forests in coastal deltaic Louisiana and northeastern South Carolina. Pages 223-253 in W.H. Conner, T.W. Doyle, K.W. Krauss (eds.), Ecology of Tidal Freshwater Forested Wetlands of the Southeastern United States. Springer. 505 p.Conner, W.H., C.T. Hackney, K.W. Krauss & J.W. Day, Jr. 2007. Tidal freshwater forested wetlands: future research needs and an overview of restoration. Pages 461-485 in W.H. Conner, T.W. Doyle, K.W. Krauss (eds.), Ecology of Tidal Freshwater Forested Wetlands of the Southeastern United States. Springer. 505 p.Gardiner, E.S. & K.W. Krauss. 2001. Photosynthetic light response of flooded cherrybark oak (Quercus pagoda) seedlings grown in two light regimes. Tree Physiology 21: 1103-1111.Krauss, K.W., R.A. Goyer, J.A. Allen & J.L. Chambers. 2000. Tree shelters effective in coastal swamp restoration (Louisiana). Ecological Restoration18: 200-201.Allen, J.A., K.W. Krauss, N.C. Duke, O. Björkman, D.R. Herbst & C. Shih. 2000. Bruguiera species in Hawai’i: systematic considerations and ecological implications. Pacific Science 54: 331-343.Doyle, T.W. & K.W. Krauss. 1999. The sands and sambars of St. Vincent Island. Florida Wildlife 53: 22-25.Krauss, K.W., J.L. Chambers & J.A. Allen. 1998. Salinity effects and differential germination of several half-sib families of baldcypress from different seed sources. New Forests 15: 53-68.Allen, J.A., W.H. Conner, R.A. Goyer, J.L. Chambers & K.W. Krauss. 1998. Chapter 4: Freshwater forested wetlands and global climate change. Pages 33-44 in G.R. Guntenspergen and B.A Vairin (eds.), Vulnerability of coastal wetlands in the Southeastern United States: climate change research results, 1992-97. U.S. Geological Survey, Biological Resources Division Biological Science Report USGS/BRD/BSR-1998-0002. 101 p. - Science
Filter Total Items: 17
Carbon and Water Budgeting Along Upper Estuaries: Developing Linkages to Environmental Change
WARC Researchers are studying carbon, water, and nutrient cycling in upper estuarine wetlands.Assessing Environmental Stress in Mature Mangrove Stands: Linkages to Nutrient Loading
WARC Researchers are comparing tree and root growth, soil CO2 flux, and surface elevation change between fertilized and unfertilized mangrove forests to assess the potential impact of increased nutrient loading and to help rate mangrove stand vulnerability.Wetland Carbon Working Group: Improving Methodologies and Estimates of Carbon and Greenhouse Gas Flux in Wetlands
WARC researchers are working to quantify the impacts of future climate and land use/land cover change on greenhouse gas emissions and reductions.Sea-level Rise Vulnerability of Mangrove Forests in Micronesia and the Pacific
The USGS and partners are studying how mangrove forests in the Federated States of Micronesia may respond to sea-level rise over the coming century. Their projections will help Micronesian communities plan for the future.Impacts of coastal and watershed changes on upper estuaries: causes and implications of wetland ecosystem transitions along the US Atlantic and Gulf Coasts
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...The Impact of Sea-Level Rise on Coral Reef and Mangrove Interactions and the Resulting Coastal Flooding Hazards
Ecosystems such as coral reefs and mangroves provide an effective first line of defense against coastal hazards and represent a promising nature-based solution to adapt to sea-level rise. In many areas, coral reefs cause waves to break and lose energy, allowing for sediment to accumulate on the inshore portion of reef flats (i.e. the shallowest, flattest part of a reef) and mangroves to establish.Science to Inform the Management of Mangrove Ecosystems Undergoing Sea Level Rise at Ding Darling National Wildlife Refuge, Sanibel Island, Florida
Mangroves are forested tidal wetlands that occur in tropical, sub-tropical, and warm temperate coastal regions around the world. Mangroves occupy a significant area of coastlines globally and provide important ecosystem services to humans and wildlife. These services include aesthetic value, storm protection, food provisioning, recreation, critical wildlife habitat, and biological carbon sequestraUnderstanding Impacts of Sea-Level Rise and Land Management on Critical Coastal Marsh Habitat
Coastal wetlands are some of the most productive and valuable habitats in the world. Louisiana contains 40% of the coastal wetlands in the United States, which provide critical habitat for waterfowl and fisheries, as well as many other benefits, such as storm surge protection for coastal communities. In terms of ecosystem services, biological resource production, and infrastructure investments, thAssessing the Benefits and Vulnerability of Current and Future Potential Ecosystem Services of the Nisqually River Delta and other Puget Sound Estuaries
The Nisqually River Delta represents the largest wetland restoration in the Pacific Northwest. The restoration resulted in a 50% increase in potential salt marsh habitat. The Delta supports threatened salmon fisheries, large populations of migratory birds, and provides unique opportunities for recreation. The Delta also provides multiple ecosystem services, which are the benefits that wildlife orImproving Our Ability to Forecast Tidal Marsh Response to Sea Level Rise
Our overall objective is to understand what controls the vulnerability of coastal marshes to risks associated with global change drivers and rising sea levels. Fundamental questions pertaining to coastal wetland vulnerability still need to be addressed. What factors explain spatial and geographic variation in tidal wetland vulnerability? How do short term climatic events (storms) influence the...Ecology of Greenhouse Gas Emissions from Coastal Wetlands
Wetlands have the potential to absorb large amounts of carbon dioxide via photosynthesis, and flooded soils have low oxygen levels which decrease rates of decomposition to promote the retention of soil carbon. However, the type of greenhouse gases emitted from wetlands varies by wetland type and soil condition. A suite of approaches are being used to assess fluxes of greenhouses gases, like...Evaluating Structural and Surface Elevation Recovery of Restored Mangroves
Hydrologic restoration is one of several approaches to rehabilitate mangroves on a large-scale. USGS evaluates how solely restoring tidal hydrologic flows affect the recovery of mangroves in Florida. - Data
Filter Total Items: 22
Above- and belowground biomass production, decomposition, and wetland elevation change in transitional coastal wetland communities exposed to elevated CO2 and sediment deposition: a mesocosm study from 2012 to 2014
This data release includes belowground primary productivity, decomposition, and surface elevation change data from a two-year mesocosm experiment from 2012 to 2014. We conducted experimental greenhouse manipulations of atmospheric CO2 (double ambient CO2) and sediment deposition to simulate a land-falling hurricane under future climate conditions. Experimental greenhouse conditions mimicked a landSimulated Methane and Nitrous Oxide Emissions under Drought-induced Saltwater Intrusion in Tidal Freshwater Forested Wetlands
This dataset contains the result of simulated daily emissions of methane (CH4) and nitrous oxide (N2O) from the soils in Tidal Freshwater Forested Wetlands (TFFW) along the Waccamaw River (SC, USA) and the Savannah River (GA and SC, USA) under drought-induced saltwater intrusion using a process-driven biogeochemistry model.Mangrove Elevation and Species' Responses to Sea-level Rise Across Pohnpei, Federated States of Micronesia
Future sea-level rise poses a risk to mangrove forests. To better understand potential vulnerability, we developed a new numerical model of soil elevation for mangrove forests. We used the model to generate projections of elevation and mangrove forest composition change under four sea-level rise scenarios through 2100 (37, 52, 67, and 117 cm by 2100). We employed a data-driven modeling approach, uFine root production in tidally influenced freshwater forested wetlands in South Carolina and Georgia, USA (2016-2017)
This dataset includes fine root productivity data that were estimated via two techniques (serial coring and root in-growth bags) in tidal freshwater wetlands and adjacent oligohaline marshes in coastal South Carolina and Georgia from March 2016 through October 2017.Soil surface elevation change and vertical accretion data to support the Fruit Farm Creek Mangrove Restoration Project (Rookery Bay National Estuarine Research Reserve, Marco Island, Florida)
These data represent surface elevation change and vertical accretion time series collected from a series of degraded tidal wetland sites near Goodland, Florida, USA. Surface elevation was measured using a combination of rod surface elevation tables (SETs) and feldspar marker horizons. Here, we document mangrove forest and soil structural changes within transects established in tidally restricted aForest structure, regeneration, and soil data to support mangrove forest damage assessment on St. John, U.S. Virgin Islands, from Hurricane Irma (2018-2019)
These data support efforts to assess mangrove forest structural response to Hurricane Irma. Data were collected from within Virgin Islands National Park in St John, U.S. Virgin Islands. Datasets include measurements of forest inventory and vitality status, woody debris, regeneration assessment, and organic soil carbon.Modeling soil pore water salinity response to drought in tidal freshwater forested wetlands
Model generated soil pore water salinity (psu) values under scenarios of drought and normal conditions at Tidal Freshwater Forested Wetlands (TFFW) sites along the Waccamaw River and Savannah River in the Southeastern United States.Rapid peat development beneath maturing mangrove forests: quantifying ecosystem changes along a 25-year chronosequence of created coastal wetlands
Mangrove forests are among the world's most productive and carbon-rich ecosystems. In addition to providing important fish and wildlife habitat and supporting coastal food webs, these coastal wetlands provide many ecosystem goods and services including clean water, stable coastlines, food, recreational opportunities, and stored carbon. Despite a growing understanding of the factors controlling manCarbon budget assessment of tidal freshwater forested wetland and oligohaline marsh ecosystems along the Waccamaw and Savannah rivers, U.S.A. (2005-2016)
Data to support carbon (C) budget assessment of tidal freshwater forested wetland and oligohaline marsh ecosystems along the Waccamaw and Savannah rivers, U.S.A. This work represents the first estimates of C standing stocks, C mass balance, soil C burial, and lateral C export to aquatic environments in tidal freshwater forested wetlands undergoing transition to oligohaline marsh.Water level and soil pore water salinity, temperature, and conductivity data in tidally influenced forested wetlands in South Carolina and Georgia
Data were collected from coastal wetlands (tidal swamps and marsh) along the Waccamaw and Savannah Rivers in South Carolina and Georgia (See Krauss et al. 2009 for additional details). Data were collected from coastal wetlands (tidal swamps and marsh) along the Waccamaw and Savannah Rivers in South Carolina and Georgia (See Krauss et al. 2009 for additional details). Data collected include water lSap flow data from a long-hydroperiod forested wetland undergoing salinity intrusion in South Carolina, USA
These data represent sap flow measurements from four tree species and were recorded every 30 minutes over several months in 2015. Data were collected from a tidally-influenced freshwater forested wetland at Strawberry Swamp, located on Hobcaw Barony, which is approximately 7 km east of Georgetown, South Carolina, USA.Forest community biomass and growth in Great Dismal Swamp, Virginia and North Carolina, USA
Forest surveys were conducted in nine 20 m x 25 m study plots, split into 3 representatives each for three forest types in Great Dismal Swamp, VA and NC, USA, December 2015 - February 2018. Trees, saplings, and shrubs were identified to species and measured for estimates of standing stocks. Standing stock data include: tree diameter at breast height (dbh), height, and condition; sapling dbh; shrub - News