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Articles 1 - 7 of 7
Full-Text Articles in Physical Sciences and Mathematics
Phosphorus Variability In The Area Of Influence Of The Mid-Barataria Sediment Diversion, Peter Mates
Phosphorus Variability In The Area Of Influence Of The Mid-Barataria Sediment Diversion, Peter Mates
LSU Master's Theses
Man-made levees along the lower Mississippi River prevent delivery of sediment from building and maintaining Louisiana’s coastal wetlands. The Mid-Barataria sediment diversions is designed to reintroduce Mississippi River water, sediment, and nutrients into the sediment-starved Barataria Basin. Phosphorus (P) is an important macronutrient for regulating primary production in coastal marine ecosystems. Wetlands can serve as a sink or source for phosphorus to the overlying water column through various retention and release processes, dependent on concentration. Louisiana coastal systems can be phosphorus limited due to much higher concentrations of bioavailable Nitrogen in river water. The high soluble molar N:P ( >50:1) …
The Tensile Root Strength Of Emergent Coastal Macrophytes, Lauris Olivia Hollis
The Tensile Root Strength Of Emergent Coastal Macrophytes, Lauris Olivia Hollis
LSU Doctoral Dissertations
Spartina patens is a dominant emergent macrophyte in fresh, intermediate, and brackish marshes along the Atlantic and Gulf coasts of United States where its biomechanical properties are a key component of wetland health and resilience. Its root biomass and tensile root strength are essential for anchorage, erosion protection, and are important determinants of soil strength. Nutrients and the herbicide atrazine are suspected of negatively impacting this wetland plant and others. The objectives of this study were to: 1) ascertain the tensile root strength of five emergent coastal macrophytes in coastal estuaries, and 2) test the effects of nutrient addition, atrazine …
Holecene Paleoenvironmental Reconstruction From The Shark River Estuary, Everglades, Florida, Qiang Yao
Holecene Paleoenvironmental Reconstruction From The Shark River Estuary, Everglades, Florida, Qiang Yao
LSU Doctoral Dissertations
This dissertation examines the paleoecological records from the Shark River Estuary in the southwestern part of the Everglades National Park (ENP), Florida, with primary goal of reconstructing the Holocene history of the coastal mangrove ecosystem in the Florida Coastal Everglades. Roughly 15 meters of sediments were collected from 4 study sites and subjected to loss-on ignition, palynological, and X-ray fluorescence analyses. According to the literature, the earliest communities of Rhizophora mangle (red mangrove) occurred prior to 8,000 cal yr BP in the south-central area of the Belize Barrier Reef Platform. Between 7,000 and 5,000 cal yr BP, Rhizophora was established …
Anthropogenic Impacts On Soil Microbial Processes In Coastal Wetlands: Nutrient Loading And Rising Co2 Levels, Havalend Ellen Steinmuller
Anthropogenic Impacts On Soil Microbial Processes In Coastal Wetlands: Nutrient Loading And Rising Co2 Levels, Havalend Ellen Steinmuller
LSU Master's Theses
Atmospheric carbon dioxide (CO2) levels and global eutrophication are anthropogenic stressors impacting the environment of specific interest in wetland systems. Wetlands occupy a critical interface between terrestrial and aquatic environments. Fertilizer use for agriculture and treated wastewater disposal has increased nutrient loading to wetlands. Conflicting results on impacts of nitrogen loading to coastal wetland soils have been reported, though most studies have investigated short-term impacts of nutrient loading, not long-term integrated impacts. I investigated an 11-year period of nutrient loading on soils in an oligohaline coastal wetland. Nitrogen treatments of 0, 50, 200, and 1200 kg ha-1 yr-1 were paired …
Spatial Structure And Dynamics Of The Plant Communities In A Pro-Grading River Delta : Wax Lake Delta, Atchafalaya Bay, Louisiana, Melissa Carle
Spatial Structure And Dynamics Of The Plant Communities In A Pro-Grading River Delta : Wax Lake Delta, Atchafalaya Bay, Louisiana, Melissa Carle
LSU Doctoral Dissertations
River deltas are dynamic depositional environments that are controlled to varying degrees by coastal and fluvial forces. Plant communities in deltas respond to many of the same allogenic forces that shape delta geomorphology. This study examines the factors that influence plant community development, productivity, and species distributions in the Wax Lake delta, a young, actively pro-grading river delta in coastal Louisiana, USA. A species distribution map created using high-resolution 8-band WorldView-2 imagery was found to have an overall accuracy of 75 percent. Classification tree analysis suggested that most of the observed variation in plant species distributions within the delta can …
Edaphic And Vegetative Controls On Mercury Cycling In Oligohaline Wetlands, Jonathan M. Willis
Edaphic And Vegetative Controls On Mercury Cycling In Oligohaline Wetlands, Jonathan M. Willis
LSU Doctoral Dissertations
With the expansion of the human population and associated industries there is a concomitant increase in both resource utilization and the production of waste and deleterious by-products. Mercury is a naturally-occurring toxic metal with a complicated and unique biogeochemical cycle, and is often a contaminant of ecotoxicological concern in unindustrialized aquatic habitats. The research described herein was designed to elucidate multiple aspects regarding the behavior of mercury in oligohaline wetland habitats, particularly with respect to edaphic and vegetative effects, through a monitoring and characterization study as well as a series of manipulative experiments. The observational study, conducted in the wetlands …
Scientific And Management Perspectives In Wetland Groundwater Hydrology, Lorna Veronica Inniss
Scientific And Management Perspectives In Wetland Groundwater Hydrology, Lorna Veronica Inniss
LSU Doctoral Dissertations
Wetland groundwater hydrology was investigated at different spatial scales to assess the usefulness of the information to coastal managers. Specific objectives were to: (1) review studies related to coastal groundwater discharge, evaluating techniques and identifying controls; (2) understand regional trends in groundwater flow along the U.S. East and Gulf coasts; (3) evaluate the applicability of naturally occurring radioisotopes as indicators of groundwater in a shallow deltaic system; and (4) evaluate groundwater-surface water exchange within Barataria Basin, Louisiana. Results of the review confirmed discharge estimates vary over several orders of magnitude, due to differences in precipitation and tidal prisms. In addition, …