Richard Day is a Geographer at the USGS Wetland and Aquatic Research Center.
Science and Products
Understanding Ecosystem Response and Infrastructure Vulnerability to Sea-Level Rise for Several National Parks and Preserves in the South Atlantic-Gulf Region
USGS Researchers at the Wetland and Aquatic Research Center and the St. Petersburg Coastal and Marine Science Center will provide valuable information to natural resource managers on how important coastal ecosystems in the National Park Service South Atlantic-Gulf Region may change over time. This information could assist with future-focused land management and stewardship.
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.
Environmental Flows and Bottomland Hardwood Habitat in the Southeastern U.S.
Environmental flows describes the quantity, quality, and timing of water flows required to sustain freshwater and estuarine ecosystems and the human livelihoods and well-being that depend on these ecosystems.
RESTORE Science: Inventory of Gulf of Mexico Ecosystem Indicators Using an Ecological Resilience Framework
To effectively manage an ecosystem, resource managers need a way to evaluate its health and ability to function. Metrics that indicate ecosystem condition - or indicators - can be used to help determine how well management strategies work.
Green-Tree Reservoir management practices within the U.S. Fish and Wildlife Service National Wildlife Refuge System
Green-Tree Reservoirs are used as a management tool by National Wildlife Refuges throughout the Southeast United States, but data suggests that forest productivity has declined in these areas. USGS investigates the effects of climate and flooding on tree growth and mortality to assist refuge managers adapt management strategies.
Ecological Implications of Mangrove Forest Migration in the Southeastern U.S.
Coastal wetlands purify water, protect coastal communities from storms, sequester (store) carbon, and provide habitat for fish and wildlife. They are also vulnerable to climate change. In particular, changes in winter climate (warmer temperatures and fewer freeze events) may transform coastal wetlands in the northern Gulf of Mexico, as mangrove forests are expected to expand their range and replac
Dissolved oxygen concentrations of Flat Lake and East Grand Lake Water Management Units of the Atchafalaya River Basin
Data were retrieved from a long-term data set for analyses of the relationship between residence time of flood waters with dissolved oxygen concentration collected as part of a long-term water quality monitoring program from 1 January 2000 through 31 December 2010 in East Grand Lake/Flat Lake Water Management Unit in the Atchafalaya River Floodway System. Dissolved oxygen data were collected biwee
Geographic distribution of black mangrove (Avicennia germinans) in coastal Louisiana in 2009
Black mangrove (Avicennia germinans (L.) L.) has historically occurred along the Louisiana coast in saline wetland habitats, but its distribution has been sparse. Mangroves are tropical to semi-tropical species and their distribution is limited by freezing temperatures. Black mangrove distribution and abundance has increased and decreased in the coastal zone of Louisiana according to freeze freque
Landscape position-based habitat modeling for the Alabama Barrier Island feasibility assessment at Dauphin Island
A barrier island habitat prediction model was used to forecast barrier island habitats (for example, beach, dune, intertidal marsh, and woody vegetation) for Dauphin Island, Alabama, based on potential island configurations associated with a variety of restoration measures and varying future conditions of storminess and sea-levels. In this study, we loosely coupled a habitat model framework with d
Temperature thresholds for black mangrove freeze damage, mortality, and recovery: refining tipping points for range expansion in a warming climate
To advance understanding of mangrove range dynamics in eastern North America, there is a need to refine temperature thresholds for mangrove freeze damage, mortality, and recovery. Here, We integrated data from 38 sites spread across the mangrove range edge in the Gulf of Mexico and Atlantic coasts of the southeastern United States, including data from a regional collaborative network called the Ma
Modeling barrier island habitats using landscape position information for Dauphin Island, Alabama
Barrier islands provide important ecosystem services, including storm protection and erosion control to the mainland, habitat for fish and wildlife, and tourism (Barbier and others, 2011; Feagin and others, 2010). These islands tend to be dynamic due to their location along the estuarine-marine interface. Besides gradual changes caused by constant forces, such as currents and tides, barrier island
Using relative topography and elevation uncertainty to delineate dune habitat on barrier islands
Dunes with a high relative topography can often be easily distinguished in high-resolution lidar-based digital elevation models (DEMs). Thus, researchers have begun using relative topography metrics, such as the topographic position index (TPI; Weiss, 2001), to identify ridges and upper slopes for extracting dunes from lidar-based DEMs (Wernette et al., 2016; Halls et al. 2018). DEMs are often use
Microclimate influences mangrove freeze damage: Implications for range expansion in response to changing macroclimate
In this data release, we present data from three nights of chilling temperatures in 2015 (18th/19th January 2015; 18th/19th February 2015; 5th/6th March 2015) and from three nights of freezing temperatures in 2017/2018 (6th/7th January 2017; 1nd/2nd January 2018; 16th/17th January 2018). In the paper that accompanies this release, we synthesized hypotheses regarding the effects of microclimatic va
Winter climate change and coastal wetland foundation species in the southeastern United States
In this study, we investigated the potential effect of winter climate change upon salt marsh and mangrove forest foundation species in the southeastern United States. Our research addresses the following three questions: (1) What is the relationship between winter climate and the presence and abundance of mangrove forests relative to salt marshes; (2) How vulnerable are salt marshes to winter clim
The impact of lidar elevation uncertainty on mapping intertidal habitats on barrier islands
These data represent low-lying lands and intertidal lands on Dauphin Island, Alabama, USA for January 2015. These data were delineated using airborne lidar elevation data, in situ elevation observations, lidar metadata, and tide gauge information. We applied Monte Carlo simulations to incorporate uncertainty into a digital elevation model and produce probabilistic outputs with regards to elevation
Barrier island habitat map and vegetation survey, Dauphin Island, AL, 2015
This dataset includes barrier island land cover types collected from mid-November 2015 to mid-December 2015 along randomly placed transects at seven sites throughout the east end of Dauphin Island. Specifically, this data collection included characterizing land cover types and measuring horizontal position and elevation. We characterized plant community composition and structure for a subset of th
Linear and nonlinear effects of temperature and precipitation on ecosystem properties in tidal saline wetlands
Macroclimatic drivers, such as temperature and rainfall regimes, greatly influence ecosystem structure and function in tidal saline wetlands. Understanding the ecological influence of macroclimatic drivers is important because it provides a foundation for anticipating the effects of climate change. Tidal saline wetlands include mangrove forests, salt marshes, and salt flats, which occupy similar g
Vegetation, soil, and landscape data
The northern Gulf of Mexico coast spans two major climate gradients and represents an excellent natural laboratory for developing climate-influenced ecological models. In this project, we used these zones of remarkable transition to develop macroclimate-based models for quantifying the regional responses of coastal wetland ecosystems to climate variation. In addition to providing important fish an
Filter Total Items: 47
Hydrologic connectivity and residence time affect the sediment trapping efficiency and dissolved oxygen concentrations of the Atchafalaya River Basin
Little is known about water movement, volume, or residence time (RT), and how those characteristics affect sediment trapping efficiency (TE) and dissolved oxygen concentrations (DO) in the United States' largest remaining bottomland hardwood swamp, the Atchafalaya River Basin. To better understand these dynamics, this study used bathymetry, lidar, and stage records to determine volumes in the Basi
Hydrologic modification and channel evolution degrades connectivity on the Atchafalaya River floodplain
The Atchafalaya River Basin is the largest remaining forested wetland in the contiguous United States. Since 1960, dredging and channel erosion in the Basin have resulted in changes to the hydrologic connectivity that have not been quantified. Analyses were conducted to determine the hydraulic and geomorphic factors that have changed since discharge became controlled that may have decreased river/
Influence of soil microbiota on Taxodium distichum seedling performance during extreme flooding events
Plant associations with soil microbiota can modulate tree seedling growth and survival via mutualistic or antagonistic interactions. It is uncertain, however, whether soil microbiota influence seedling growth of coastal trees when exposed to extreme flooding regimes. We evaluated the role of soil microbes in promoting baldcypress (Taxodium distichum) seedling performance under different inundation
Salinity, water level, and forest structure contribute to baldcypress (Taxodium distichum) rhizosphere and endosphere community structure
As rising sea levels alter coastal ecosystems, there is a pressing need to examine the effects of saltwater intrusion on coastal communities. Using 16S Illumina profiling, we characterized the communities of baldcypress tree (Taxodium distichum) root endosphere and rhizosphere soil bacteria. Our study utilized established sites along salinity and flooding gradients in the United States of Georgia,
Frequency of extreme freeze events controls the distribution and structure of black mangroves (Avicennia germinans) near their northern range limit in coastal Louisiana
AimClimate change is expected to result in the tropicalization of coastal wetlands in the northern Gulf of Mexico, as warming winters allow tropical mangrove forests to expand their distribution poleward at the expense of temperate salt marshes. Data limitations near mangrove range limits have hindered understanding of the effects of winter temperature extremes on mangrove distribution and structu
Divergent biotic and abiotic filtering of root endosphere and rhizosphere soil fungal communities along ecological gradients
Plant roots assemble two distinct microbial compartments: the rhizosphere (microbes in soil surrounding roots) and the endosphere (microbes within roots). Our knowledge of fungal community assembly in these compartments is limited, especially in wetlands. We tested the hypothesis that biotic factors would have direct effects on rhizosphere and endosphere assembly, while abiotic factors would have
Temperature thresholds for black mangrove (Avicennia germinans) freeze damage, mortality, and recovery in North America: Refining tipping points for range expansion in a warming climate
Near the tropical‐temperate transition zone, warming winter temperatures are expected to facilitate the poleward range expansion of freeze‐sensitive tropical organisms. In coastal wetlands of eastern and central North America, freeze‐sensitive woody plants (mangroves) are expected to expand northward into regions currently dominated by freeze‐tolerant herbaceous salt marsh plants. To advance under
Channel modification and evolution alter hydraulic connectivity in the Atchafalaya River basin increasing vulnerability to sea-level rise
Channel dredging and erosion in the Atchafalaya River basin have resulted in changes to the hydraulic connectivity of this floodplain swamp that have not been previously quantified. In this study, analyses were conducted to determine hydraulic and geomorphic factors that have changed since channel closure in 1962. Results indicated changes occurred in the Atchafalaya main channel cross-section bet
Modeling barrier island habitats using landscape position information
Barrier islands are dynamic environments because of their position along the marine–estuarine interface. Geomorphology influences habitat distribution on barrier islands by regulating exposure to harsh abiotic conditions. Researchers have identified linkages between habitat and landscape position, such as elevation and distance from shore, yet these linkages have not been fully leveraged to develo
Advancing barrier island habitat mapping using landscape position information
Barrier islands are dynamic ecosystems that change gradually from coastal processes, including currents and tides, and rapidly from episodic events, such as storms. These islands provide many important ecosystem services, including storm protection and erosion control to the mainland, habitat for fish and wildlife, and tourism. Habitat maps, developed by scientists, provide a critical tool for mon
Microclimate influences mangrove freeze damage: Implications for range expansion in response to changing macroclimate
In response to warming winter air temperatures, freeze-sensitive mangrove forests are expected to expand at the expense of freeze-tolerant salt marshes. To better anticipate and prepare for mangrove range expansion, there is a need to advance understanding of the modulating role of microclimate. Here, we synthesized hypotheses regarding the effects of microclimatic variation on temperature gradien
Science and Products
- Science
Understanding Ecosystem Response and Infrastructure Vulnerability to Sea-Level Rise for Several National Parks and Preserves in the South Atlantic-Gulf Region
USGS Researchers at the Wetland and Aquatic Research Center and the St. Petersburg Coastal and Marine Science Center will provide valuable information to natural resource managers on how important coastal ecosystems in the National Park Service South Atlantic-Gulf Region may change over time. This information could assist with future-focused land management and stewardship.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.Environmental Flows and Bottomland Hardwood Habitat in the Southeastern U.S.
Environmental flows describes the quantity, quality, and timing of water flows required to sustain freshwater and estuarine ecosystems and the human livelihoods and well-being that depend on these ecosystems.RESTORE Science: Inventory of Gulf of Mexico Ecosystem Indicators Using an Ecological Resilience Framework
To effectively manage an ecosystem, resource managers need a way to evaluate its health and ability to function. Metrics that indicate ecosystem condition - or indicators - can be used to help determine how well management strategies work.Green-Tree Reservoir management practices within the U.S. Fish and Wildlife Service National Wildlife Refuge System
Green-Tree Reservoirs are used as a management tool by National Wildlife Refuges throughout the Southeast United States, but data suggests that forest productivity has declined in these areas. USGS investigates the effects of climate and flooding on tree growth and mortality to assist refuge managers adapt management strategies.Ecological Implications of Mangrove Forest Migration in the Southeastern U.S.
Coastal wetlands purify water, protect coastal communities from storms, sequester (store) carbon, and provide habitat for fish and wildlife. They are also vulnerable to climate change. In particular, changes in winter climate (warmer temperatures and fewer freeze events) may transform coastal wetlands in the northern Gulf of Mexico, as mangrove forests are expected to expand their range and replac - Data
Dissolved oxygen concentrations of Flat Lake and East Grand Lake Water Management Units of the Atchafalaya River Basin
Data were retrieved from a long-term data set for analyses of the relationship between residence time of flood waters with dissolved oxygen concentration collected as part of a long-term water quality monitoring program from 1 January 2000 through 31 December 2010 in East Grand Lake/Flat Lake Water Management Unit in the Atchafalaya River Floodway System. Dissolved oxygen data were collected biweeGeographic distribution of black mangrove (Avicennia germinans) in coastal Louisiana in 2009
Black mangrove (Avicennia germinans (L.) L.) has historically occurred along the Louisiana coast in saline wetland habitats, but its distribution has been sparse. Mangroves are tropical to semi-tropical species and their distribution is limited by freezing temperatures. Black mangrove distribution and abundance has increased and decreased in the coastal zone of Louisiana according to freeze frequeLandscape position-based habitat modeling for the Alabama Barrier Island feasibility assessment at Dauphin Island
A barrier island habitat prediction model was used to forecast barrier island habitats (for example, beach, dune, intertidal marsh, and woody vegetation) for Dauphin Island, Alabama, based on potential island configurations associated with a variety of restoration measures and varying future conditions of storminess and sea-levels. In this study, we loosely coupled a habitat model framework with dTemperature thresholds for black mangrove freeze damage, mortality, and recovery: refining tipping points for range expansion in a warming climate
To advance understanding of mangrove range dynamics in eastern North America, there is a need to refine temperature thresholds for mangrove freeze damage, mortality, and recovery. Here, We integrated data from 38 sites spread across the mangrove range edge in the Gulf of Mexico and Atlantic coasts of the southeastern United States, including data from a regional collaborative network called the MaModeling barrier island habitats using landscape position information for Dauphin Island, Alabama
Barrier islands provide important ecosystem services, including storm protection and erosion control to the mainland, habitat for fish and wildlife, and tourism (Barbier and others, 2011; Feagin and others, 2010). These islands tend to be dynamic due to their location along the estuarine-marine interface. Besides gradual changes caused by constant forces, such as currents and tides, barrier islandUsing relative topography and elevation uncertainty to delineate dune habitat on barrier islands
Dunes with a high relative topography can often be easily distinguished in high-resolution lidar-based digital elevation models (DEMs). Thus, researchers have begun using relative topography metrics, such as the topographic position index (TPI; Weiss, 2001), to identify ridges and upper slopes for extracting dunes from lidar-based DEMs (Wernette et al., 2016; Halls et al. 2018). DEMs are often useMicroclimate influences mangrove freeze damage: Implications for range expansion in response to changing macroclimate
In this data release, we present data from three nights of chilling temperatures in 2015 (18th/19th January 2015; 18th/19th February 2015; 5th/6th March 2015) and from three nights of freezing temperatures in 2017/2018 (6th/7th January 2017; 1nd/2nd January 2018; 16th/17th January 2018). In the paper that accompanies this release, we synthesized hypotheses regarding the effects of microclimatic vaWinter climate change and coastal wetland foundation species in the southeastern United States
In this study, we investigated the potential effect of winter climate change upon salt marsh and mangrove forest foundation species in the southeastern United States. Our research addresses the following three questions: (1) What is the relationship between winter climate and the presence and abundance of mangrove forests relative to salt marshes; (2) How vulnerable are salt marshes to winter climThe impact of lidar elevation uncertainty on mapping intertidal habitats on barrier islands
These data represent low-lying lands and intertidal lands on Dauphin Island, Alabama, USA for January 2015. These data were delineated using airborne lidar elevation data, in situ elevation observations, lidar metadata, and tide gauge information. We applied Monte Carlo simulations to incorporate uncertainty into a digital elevation model and produce probabilistic outputs with regards to elevationBarrier island habitat map and vegetation survey, Dauphin Island, AL, 2015
This dataset includes barrier island land cover types collected from mid-November 2015 to mid-December 2015 along randomly placed transects at seven sites throughout the east end of Dauphin Island. Specifically, this data collection included characterizing land cover types and measuring horizontal position and elevation. We characterized plant community composition and structure for a subset of thLinear and nonlinear effects of temperature and precipitation on ecosystem properties in tidal saline wetlands
Macroclimatic drivers, such as temperature and rainfall regimes, greatly influence ecosystem structure and function in tidal saline wetlands. Understanding the ecological influence of macroclimatic drivers is important because it provides a foundation for anticipating the effects of climate change. Tidal saline wetlands include mangrove forests, salt marshes, and salt flats, which occupy similar gVegetation, soil, and landscape data
The northern Gulf of Mexico coast spans two major climate gradients and represents an excellent natural laboratory for developing climate-influenced ecological models. In this project, we used these zones of remarkable transition to develop macroclimate-based models for quantifying the regional responses of coastal wetland ecosystems to climate variation. In addition to providing important fish an - Publications
Filter Total Items: 47
Hydrologic connectivity and residence time affect the sediment trapping efficiency and dissolved oxygen concentrations of the Atchafalaya River Basin
Little is known about water movement, volume, or residence time (RT), and how those characteristics affect sediment trapping efficiency (TE) and dissolved oxygen concentrations (DO) in the United States' largest remaining bottomland hardwood swamp, the Atchafalaya River Basin. To better understand these dynamics, this study used bathymetry, lidar, and stage records to determine volumes in the BasiHydrologic modification and channel evolution degrades connectivity on the Atchafalaya River floodplain
The Atchafalaya River Basin is the largest remaining forested wetland in the contiguous United States. Since 1960, dredging and channel erosion in the Basin have resulted in changes to the hydrologic connectivity that have not been quantified. Analyses were conducted to determine the hydraulic and geomorphic factors that have changed since discharge became controlled that may have decreased river/Influence of soil microbiota on Taxodium distichum seedling performance during extreme flooding events
Plant associations with soil microbiota can modulate tree seedling growth and survival via mutualistic or antagonistic interactions. It is uncertain, however, whether soil microbiota influence seedling growth of coastal trees when exposed to extreme flooding regimes. We evaluated the role of soil microbes in promoting baldcypress (Taxodium distichum) seedling performance under different inundationSalinity, water level, and forest structure contribute to baldcypress (Taxodium distichum) rhizosphere and endosphere community structure
As rising sea levels alter coastal ecosystems, there is a pressing need to examine the effects of saltwater intrusion on coastal communities. Using 16S Illumina profiling, we characterized the communities of baldcypress tree (Taxodium distichum) root endosphere and rhizosphere soil bacteria. Our study utilized established sites along salinity and flooding gradients in the United States of Georgia,Frequency of extreme freeze events controls the distribution and structure of black mangroves (Avicennia germinans) near their northern range limit in coastal Louisiana
AimClimate change is expected to result in the tropicalization of coastal wetlands in the northern Gulf of Mexico, as warming winters allow tropical mangrove forests to expand their distribution poleward at the expense of temperate salt marshes. Data limitations near mangrove range limits have hindered understanding of the effects of winter temperature extremes on mangrove distribution and structuDivergent biotic and abiotic filtering of root endosphere and rhizosphere soil fungal communities along ecological gradients
Plant roots assemble two distinct microbial compartments: the rhizosphere (microbes in soil surrounding roots) and the endosphere (microbes within roots). Our knowledge of fungal community assembly in these compartments is limited, especially in wetlands. We tested the hypothesis that biotic factors would have direct effects on rhizosphere and endosphere assembly, while abiotic factors would haveTemperature thresholds for black mangrove (Avicennia germinans) freeze damage, mortality, and recovery in North America: Refining tipping points for range expansion in a warming climate
Near the tropical‐temperate transition zone, warming winter temperatures are expected to facilitate the poleward range expansion of freeze‐sensitive tropical organisms. In coastal wetlands of eastern and central North America, freeze‐sensitive woody plants (mangroves) are expected to expand northward into regions currently dominated by freeze‐tolerant herbaceous salt marsh plants. To advance underChannel modification and evolution alter hydraulic connectivity in the Atchafalaya River basin increasing vulnerability to sea-level rise
Channel dredging and erosion in the Atchafalaya River basin have resulted in changes to the hydraulic connectivity of this floodplain swamp that have not been previously quantified. In this study, analyses were conducted to determine hydraulic and geomorphic factors that have changed since channel closure in 1962. Results indicated changes occurred in the Atchafalaya main channel cross-section betModeling barrier island habitats using landscape position information
Barrier islands are dynamic environments because of their position along the marine–estuarine interface. Geomorphology influences habitat distribution on barrier islands by regulating exposure to harsh abiotic conditions. Researchers have identified linkages between habitat and landscape position, such as elevation and distance from shore, yet these linkages have not been fully leveraged to develoAdvancing barrier island habitat mapping using landscape position information
Barrier islands are dynamic ecosystems that change gradually from coastal processes, including currents and tides, and rapidly from episodic events, such as storms. These islands provide many important ecosystem services, including storm protection and erosion control to the mainland, habitat for fish and wildlife, and tourism. Habitat maps, developed by scientists, provide a critical tool for monMicroclimate influences mangrove freeze damage: Implications for range expansion in response to changing macroclimate
In response to warming winter air temperatures, freeze-sensitive mangrove forests are expected to expand at the expense of freeze-tolerant salt marshes. To better anticipate and prepare for mangrove range expansion, there is a need to advance understanding of the modulating role of microclimate. Here, we synthesized hypotheses regarding the effects of microclimatic variation on temperature gradien