Healthy Coastal Ecosystems Virtual Oral Abstracts
Dec 02, 2020 11:45 AM - Dec 31, 2020 01:15 PM(America/Chicago)
20201202T1145 20201202T1315 America/Chicago Healthy Coastal Ecosystems - Wetland Ecology (Oral)

Development, resource extraction, climate change and other anthropogenic stressors on coastal ecosystems are issues of management concern. Scientists and stakeholders are attempting to understand such impacts and find integrative coastal management strategies. The seascape changes that may occur to coastal habitats because of these stressors can be dire. For example, changes in the hydrogeomorphology of a landscape combined impacts of subsidence, sea level rise and alterations in freshwater flow may have negative impacts on coastal habitats. They may also have cascading impacts on the many species residing in these habitats. The focus of this track is to present research, policy and educational opportunities and tools that have been used to improve our understanding of habitat vulnerability. This track is intended to provide a venue for scientists and managers to share their insights about habitat protection, conservation and restoration in light of the inevitable changes to our coasts.

Virtual 2020 Bays and Bayous Symposium melissa.schneider@usm.edu
National Oceanic and Atmospheric Administration logoMobile Bay National Estuary Program logoMississippi-Alabama Sea Grant Consortium logoThe University of Southern Mississippi  logoDauphin Island Sea Lab Foundation logoAlabama State Port Authority logoMississippi Commercial Fisheries United logoGulf of Mexico Alliance logoHydro, LLC logoNorthern Gulf Institute logoGoodwyn Mills & Cawood, Inc. logoNeel-Schaffer, inc. logoHeadwaters LLC logoStantec Consulting Services Inc. logoDog River Clearwater Revival logoEnvironmental Science Associates (ESA) logoThompson Engineering logo

Development, resource extraction, climate change and other anthropogenic stressors on coastal ecosystems are issues of management concern. Scientists and stakeholders are attempting to understand such impacts and find integrative coastal management strategies. The seascape changes that may occur to coastal habitats because of these stressors can be dire. For example, changes in the hydrogeomorphology of a landscape combined impacts of subsidence, sea level rise and alterations in freshwater flow may have negative impacts on coastal habitats. They may also have cascading impacts on the many species residing in these habitats. The focus of this track is to present research, policy and educational opportunities and tools that have been used to improve our understanding of habitat vulnerability. This track is intended to provide a venue for scientists and managers to share their insights about habitat protection, conservation and restoration in light of the inevitable changes to our coasts.

Understanding the importance of wetland ecosystems for water quality and quantity in a costal watershedView Abstract Watch Recording
Oral Presentation 11:45 AM - 12:00 Noon (America/Chicago) 2020/12/02 17:45:00 UTC - 2020/12/31 18:00:00 UTC
This study aims at evaluating the effects of wetlands on downstream flow, nitrate, organic nitrogen, and phosphate loading in the Fish River watershed (FRW), located in Baldwin County, coastal Alabama. The FRW drains to the Weeks Bay and represents approximately 75% of the freshwater inputs of this sub-estuary of the Mobile Bay. The Weeks Bay is one of the few designed Outstanding National Resources Water in Alabama and has experienced a significant loss of natural land cover over the past two decades. Consequently, it is of the utmost importance to assess the importance of natural ecosystems such as wetlands in the water quality purification of this pristine watershed. We set up a SWAT model that captured the spatial distribution of 44 major wetlands across the FRW. The SWAT model was calibrated using flow and water quality data available at the watershed outlet by performing 500 simulations from 2008 to 2015. The results yielded daily NSE values of 0.87, 0.86, and 0.54 for streamflow, phosphate, and nitrate, respectively. The upper (90%) and lower limits (10%) of the prediction interval along with the medians of the SWAT generated nutrient loadings and discharge to each wetland were fed as input data to the process-based WetQual model. The outputs of WetQual were then incorporated back into SWAT as point sources and SWAT was rerun. The SWAT-WetQual coupling was automated through a FORTRAN routine. The removal efficiencies of the 44 wetlands were found to be 13-15%, 26-45%, and 65-69% for nitrate, organic nitrogen, and phosphate, respectively. The median removal efficiencies at the watershed outlet were estimated at 5.4%, 28%, 56% for nitrate, organic nitrogen, and phosphate, respectively.
Presenters
HH
Henrique Haas
Auburn University
Co-authors
SI
Sabahattin Isik
Auburn University
LK
Latif Kalin
MH
Mohamed Hantush
EPA
Non-Linear Responses of Wetland Sediment Microbiota to SalinityView Abstract Watch Recording
Oral Presentation 12:00 Noon - 12:15 PM (America/Chicago) 2020/12/02 18:00:00 UTC - 2020/12/31 18:15:00 UTC
Despite the central role of wetland microbial communities in nutrient cycling and carbon sequestration, little is known of how sediment bacteria differ by salinity, particularly between fresh, intermediate, brackish, and saltmarshes. In this study, the sediment bacterial community and extracellular enzyme activity of 22 wetlands along the Gulf and Atlantic coasts of the southeastern U.S. were surveyed. This included nine tidally connected pairs of wetlands, differing in salinity regime but separated by < 20 km. Disentangling sediment bacterial dynamics in response to salinity variation at multiple temporal (0-300 days), concentration (0 ppt – 39 ppt), and geospatial scales (0 km – 2,000 km) is necessary to better predict the impacts of saltwater intrusion on the wetland microbiome. Five sediment cores were taken from each site and separated into surface and root-zone fractions. Bacterial DNA was extracted, the V4 region of the 16S rRNA gene amplified, and amplicons sequenced using Illumina MiSeq. Activities of the extracellular enzymes β-glucosidase, NAGase, peroxidase, phenol oxidase, and acid phosphatase were assayed to infer mineralization rates of cellulose, lignin, chitin, and organic phosphates. Wetland bacterial communities differed significantly by salinity (p< 0.001) and each pairwise comparison of wetland salinity class was significant (p=0.006). Ordinations show a stepwise differentiation of bacterial composition from freshwater to saltwater. Ordination distances between bacterial communities at different salinity levels revealed a strong but non-linear response, with low levels of salinity increase (0 ppt – 5 ppt) as well as salinity increases across the saltmarsh domain (18 ppt – 30 ppt) having much stronger effects than across brackish salinity marshes (5 ppt – 18 ppt). Enzyme activity also varied non-linearly, but generally decreased with salinity. Thus, even small changes in salinity may have large impacts on coastal microbiomes.
Presenters Eric Weingarten
University Of Mississippi
Co-authors
CJ
Colin Jackson
University Of Mississippi
Distribution, Density, and Habitat Associations of Non-breeding, Tidal Marsh Birds in MississippiView Abstract Watch Recording
Oral Presentation 12:15 PM - 12:30 PM (America/Chicago) 2020/12/02 18:15:00 UTC - 2020/12/31 18:30:00 UTC
Secretive marsh birds are difficult to survey for, especially during the non-breeding season when vocalizations are infrequent, complicating population estimation efforts. While some breeding population assessments have been performed, dynamics of marsh bird populations, especially during the non-breeding season along the northern coast of the Gulf of Mexico, remain relatively unknown. To address the void in non-breeding season population information for marsh birds along the coast of Mississippi, we conducted line transect surveys distributed across a spatially-balanced sampling framework of Mississippi tidal marshes December – February, 2018–2020. Using hierarchical distance sampling models for unmarked populations, we estimated species-specific non-breeding population densities and habitat associations of eight marsh bird species across a mosaic of tidal marsh communities, spanning oligohaline to polyhaline emergent and open marsh systems. Marsh Wrens (Cistothorus palustris) were encountered most (n = 1,593) among all surveyed marsh complexes with an estimated coast-wide density of 5.18 ± 1.13 birds/ha. Clapper Rails (Rallus crepitans; n = 606) were also widespread but less dense (0.78 ± 0.33 birds/ha). Seaside Sparrows (Ammospiza maritima; n = 410) on the other hand were more localized within the broader tidal marsh ecosystem with estimated densities ranging from zero when undetected to 3.37 ± 0.78 birds/ha at the Hancock County marsh complex. This study provides the first statewide, non-breeding density estimates for tidal marsh birds along the Mississippi Coast and the first data of these kind for the northern Gulf of Mexico region. These population estimates and density distributions also help increase our understanding of the non-breeding season avian community composition within tidal marshes.
Presenters
SW
Spencer Weitzel
Mississippi State University
Co-authors
JF
Jared Feura
Mississippi State University
RI
Ray B. Iglay
Mississippi State University
KE
Kristine Evans
Mississippi State University
SR
Scott Rush
Mississippi State University
MW
Mark S. Woodrey
Mississippi State University
Diurnal and Vegetation based Geochemical Activity in Mangrove Marsh Ecosystems View Abstract Watch Recording
Oral Presentation 12:30 PM - 12:45 PM (America/Chicago) 2020/12/02 18:30:00 UTC - 2020/12/31 18:45:00 UTC
Mangrove ecosystems are highly productive and can store disproportionate amounts of carbon in their sediment that may be metabolized to methane by methanogens. Methane can then be released to the atmosphere through outgassing. By evaluating the structure and function of microbial communities in mangrove sediments, more can be understood about the role mangrove systems play in the carbon cycle. We investigated the methane flux in mangrove-dominated, Spartina-dominated, and seagrass-dominated sediments at Mission-Aransas National Estuarine Research Reserve in South Texas. Atmospheric concentrations of methane, carbon dioxide, and sulfide were measured using a gas analyzer connected to a flux chamber. Mangrove-dominated and Spartina-dominated sediment had greater concentrations of methane than seagrass-dominated sediment. Complementary data for dissolved ammonium, nitrate, sulfate, and sulfide within the porewater showed similar trends. These results show that diurnal variability may have a significant impact on how methane emissions are modeled. Sediment from 2, 12, and 20 cm were sequenced using Illumina HiSeq for metagenomes and metatranscriptomes. The 16S rRNA genes and 16S rRNA transcripts from the metagenomes and metatranscriptomes, respectively, were investigated to compare community structure. Genes pertaining to geochemical pathways were compared between 54 metagenome samples. Sulfur cycling genes (soxZ, dsrC, dsrH) were expressed in August mangrove samples at 12 cm along with the increased expression of genes associated with carbon fixation. Further work will be done to investigate microbial community structure and function with regard to observed methane emissions.
Presenters Rachel Weisend
Texas A And M University Corpus Christi
Co-authors
BK
Brandi Kiel Reese
University Of South Alabama, Dauphin Island Sea Lab
MM
Megan Mullis
Texas A&M University Corpus Christi
BB
Brett Baker
University Of Texas Marine Science Institute
IR
Ian Rambo
University Of Texas Marine Science Institute
Texas A and M University Corpus Christi
Mississippi State University
University of Mississippi
Auburn University
No moderator for this session!
Auburn University Department of Geosciences
 Kelly Correia
University of South Alabama/Dauphin Island Sea Lab
Ms. Sandra Huynh
Grand Bay NERR
USM Division of Coastal Sciences
The University of Southern Missisippi
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