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Presentations NSF Site Review 2009 Georgia Coastal Research Council Overview
Abstract - (none)
(contributed by Janice Flory, 2009)
PDF file
    Natural and Human Impacts on Back-barrier Islands of Georgia
Abstract - Both natural processes (e.g., erosion, vegetative succession, changes in sea level) and human processes (e.g., prehistoric shell deposition, modern clearing) have impacted the structure of back-barrier islands on the coast of Georgia. Both types of processes have occurred continually throughout the past and present. Present-day-back-barrier islands cannot be understood without a thorough knowledge of their landscape history. Thus for a more complete understanding of present-day estuarine ecosystem processes, past and present human activity must be taken into consideration.
(contributed by John Turck, 2009)
PDF file
    Temporal and Spatial Trends in Nitrogen and Phosphorus Inputs to The Watershed of the Altamaha River
Abstract - The watershed of the Altamaha River, Georgia, is one of the largest in the southeastern U.S., draining 36,718 km2 (including parts of metro Atlanta). We calculated both nitrogen (fertilizer, net food and feed import, atmospheric deposition, and biological N fixation in agricultural and forest lands) and phosphorus (fertilizer and net food and feed import) inputs to the watershed for 6 time points between 1954 and 2002. Total N inputs rose from 1,943 kg N km-2 yr-1 in 1954 to a peak of 3,584 kg N km-2 yr-1 in 1982 and then declined again to 2,566 kg N km-2 yr-1 by 2002. Phosphorus inputs rose from 408 kg P km-2 yr-1 in 1954 to 531 kg P km-2 yr-1 in 1974 before also declining again, to 410 kg P km-2 yr-1 in 2002. These changes were primarily driven by agricultural inputs and were dominated by changes in fertilizer use. Fertilizer tended to be the most important input of both N and P to the watershed, although net food and feed import increased in importance over time and was the dominant source of N input by 2002. When considered on an individual basis, fertilizer input tended to be highest in the middle portions of the watershed (Little and Lower Ocmulgee and Lower Oconee sub-basins) whereas net food and feed imports were highest in the upper reaches (Upper Oconee and Upper Ocmulgee sub-basins). Although the overall trend in recent years has been towards decreases in both N and P inputs, these trends may be offset due to continuing increases in animal and human populations.
(contributed by Sylvia Schaefer, 2009)
MS PowerPoint
    Understanding Plant Distributions Surrounding Marsh Hammocks Within the Georgia Coastal Ecosystems LTER
Abstract - Accurate habitat mapping in salt marshes is important for both management and conservation goals, as it provides information essential for identifying sensitive areas and documenting changes over time as the result of sea level rise or human perturbations. The goal of this study is to characterize patterns of marsh plant distribution in the salt marshes surrounding back barrier islands (hammocks) within the Georgia Coastal Ecosystems LTER. In the summer of 2007 the GCE LTER surveyed over 50 hammocks of different origin and size. Sub-meter accuracy GPS units were used to map the hammock upland border and the extent of the upper marsh (from the hammock border to the upper edge of Spartina alterniflora, i.e. the marsh “halo”), and plants within the halo were characterized. Analysis of these data showed that marsh plant community composition directly adjacent to the upland border is affected by both the size and origin of the hammock. Additionally, there are significant differences in both the mean halo width and the dominant plant species in relation to hammock size and origin. I am currently using Light Detection and Ranging (LIDAR) data in combination with hyperspectral aerial imagery to map plant species to elucidate how elevation, in addition to proximity to uplands, determines marsh plant distributions.
(contributed by Christine Hladik, 2009)
MS PowerPoint
    GCE Midterm review, Education
Abstract - (none)
(contributed by Steve Pennings, 2009)
MS PowerPoint
    Georgia Coastal Ecosystems LTER - Information Management Overview
Abstract - (none)
(contributed by Wade Sheldon, 2009)
MS PowerPoint
  NSF Site Review 2015 Georgia Coastal Ecosystems LTER - Information Management Highlights
Abstract - (none)
(contributed by Wade Sheldon, 2018)
PDF file
    Georgia Coastal Ecosystems LTER - Information Management Overview
Abstract - (none)
(contributed by Wade Sheldon, 2018)
PDF file
  Oral Presentations Using the GCE Data Toolbox to automate environmental data processing and produce EML-described data packages for the EDI repository
Abstract - (none)
(contributed by Wade M. Sheldon, 2019)
PDF file
    Multidecadal biomass declines and controlling variables for the keystone salt marsh species, Spartina alterniflora, in coastal Georgia
Abstract - We studied aboveground biomass dynamics and spatial patterns of Marsh Cordgrass, Spartina alterniflora, on the Central Georgia Coast. This keystone species accounts for 98% of the aerial extent of salt marshes in Georgia and comprise about 33% of all salt marsh on the U.S. Western Atlantic Coast. Geospatial techniques were used to scale up in situ biomass measurements within the NSF Georgia Coastal Ecosystems research domain on the Central Georgia Coast to landscape scale estimates using 290 Landsat 5 TM scenes from 1984 to 2011. Climate and hydrological variables were then used to explain variations in aboveground production for each of the three height classes of S. alterniflora. River discharge, total precipitation, minimum temperature, and mean sea level had positive relationships with and best explained biomass variation for all dates. Over the 28-year study period we documented biomass declines of 31.6 %, 33.4 %, and 38.7% for tall, medium, and short S. alterniflora height classes. These biomass declines were linked to increased drought severity and frequency over the last half of our study period. We then applied a larger, synoptic scale approach to riverine and tidal watersheds containing 620 square kilometers of S. alterniflora marshlands on the Georgia Coast (Savannah River to St Simon’s Sound) and found similar inter and intra-annual biomass patterns. Importantly, S. alterniflora biomass production was greatest in areas closest to larger inputs of freshwater and high precipitation. We infer that these areas of high production, especially in the Lower Altamaha River Watershed, were better buffered against drought stress, including soil salinization, and also experienced greater nitrogen loading rates. Overall, this much larger study area experienced a 20.6% average decline, representing a reduction of about 108,000 MT in aboveground live carbon biomass. This loss in marsh production presumably affects valuable ecosystem services, including wetland soil carbon sequestration and organic matter export (both particulate and dissolved). Thus, declines in marsh production could significantly reduce nutritional support to food webs and carbon biogeochemical cycling, as well as commercial fish and shellfish production, in Georgia’s estuaries and coastal ocean ecosystems. Finally, we are carrying our analyses forward using newer Landsat 8 OLI imagery. In addition, Landsat 7 ETM imagery is serving as a “bridge” to cross-calibrate between the Landsat 5 and Landsat 8 sensors and provide “gap coverage” between 2011 and 2014.
(contributed by John F. Schalles, 2018)
Web link
    Spatial and temporal perpectives on multiple stressor impacts spanning inland to coastal ecosystems
Abstract - This talk will provide perspectives on aquatic ecosystem stress responses acquired from 40+ years of field experiences in inland, estuarine, and coastal waters. Increasing, our study units are expressing multiple stressors and accelerated rates of ecosystem response. I'll use several examples from larger scale, synoptic studies using remote sensing to examine salt marshes, algal blooms, and fates of suspended sediments. Finally, I'll emphasize the value of place-based, local knowledge and talking with the stake-holders experiencing changes in aquatic systems.
(contributed by John F. Schalles, 2018)
Web link
    Using drones for high spatial and temporal resolution - Long term observations
Abstract - This workshop will introduce researchers to the use of drones for imaging study sites and best practices for creating actionable products and time series. We will start with the basics: FAA licensing, flight training, and designing a mission plan. We will discuss avoiding common hazards such as adverse weather conditions and low flying aircraft. The workshop will cover the use of color and multi / hyperspectral imaging, including the use of ground control points for georeferencing and reflectance panels for image calibration. We will demonstrate software for creating orthomosaics of drone imagery and performing common classification techniques. Finally, we will discuss the scaling of this high-resolution imagery to space-borne remote sensing technologies.
(contributed by Tom Bell, 2018)
Web link
    Tools for Sensor Data Quality Control
Abstract - Regardless of Q/A procedures, data quality issues are guaranteed with environmental sensor data. Without good Q/C data users can draw invalid conclusions (untrustworthy data). Therefore Q/C analysis is a critical part of any monitoring program.
(contributed by Wade M. Sheldon, 2017)
PDF file
    EML Packages from the GCE Data Toolbox
Abstract - (none)
(contributed by Wade M. Sheldon, 2017)
PDF file
    Serious declines in a large area of Georgia Salt marsh plant biomass are linked to climate variables
Abstract - In initial work, we studied aboveground biomass dynamics and spatial patterns of Spartina alterniflora, the keystone species of Central Georgia’s salt marshes. Geospatial techniques were used to scale up in situ biomass measurements to landscape scale and applied to 290 Landsat 5 TM scenes from 1984 to 2011. We documented biomass declines of 31.6 %, 33.4 %, and 38.7% for tall, medium, and short Spartina classes. The declines strongly correlated with increased drought frequency and severity and coincided with marsh die-back events and increased snail grazing. To explain temporal patterns, we compared biomass estimates with a suite of abiotic drivers. River discharge, total precipitation, Palmer Drought Severity Index, and mean sea level best explained biomass variations. We then extended our analysis to a much larger area (620 km2; St. Simons Sound to the Savannah River) and found the same inter and intra-annual biomass patterns. Moreover, higher biomass was associated with proximity to larger rivers (Altamaha, Ogeechee, and Savannah) and greater precipitation. In 2001, after an extended and severe drought, there was little net growth between late winter and fall and many marsh areas had net biomass loss. We’re now using Landsat 7 and 8 imagery to update our analysis to the present time. Collectively, these approaches address a key question: Are the serious declines we documented in Spartina alterniflora biomass and marsh health cyclical, or are they longer-term, directional trends related to climate change?
(contributed by J.P. O'Donnell, 2017)
Web link
65 Records
LTER
NSF

This material is based upon work supported by the National Science Foundation under grants OCE-9982133, OCE-0620959, OCE-1237140 and OCE-1832178. Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.