Digital Commons Network^™

Using 2d Hec-Ras Modeling With Vertical Feature Extraction To Inform Ecological Design In The Lower Atchafalaya River Basin, Louisiana, Colin Anderson

LSU Master's Theses

A 2D HEC-RAS model was created to demonstrate applications of hydraulic modeling for informing ecological design. This was done by comparing the hydrologic conditions of a baseline year (2010) to that of the environmental flow prescription from Kozak et al. (2016). The inundation results are relevant to hydraulic connectivity and cypress regeneration.

The hydraulic model was created by assimilating numerous data sources, refining the model with vertical feature (VF) extraction, and calibrating/validating the model. Several topo-bathymetric sources were combined to create the digital elevation model (DEM). Most importantly, this included bathymetry of the backswamp. Polylines of significant VFs in the …

Changes In Wetland Soil Processes And Ecosystem Functions Six Years After Marsh Creation In Barataria Bay, Louisiana, Erol R. Knaus

LSU Master's Theses

Louisiana contains about 40% of the conterminous United States coastal and estuarine wetlands but also has the highest rates of wetland loss at around 80% of the total. Approximately 4,900 km² of coastal land in Louisiana has been lost since 1930. Our study location, Barataria Bay, has one of the highest coastal wetland erosion rates in the nation, at ∼41 km² per year; and therefore, is a high priority for wetland restoration activities. In 2014, sandy sediment dredged from the bed of the Mississippi River was placed in Barataria Bay as part of a restoration effort. Samples were …

Coupled Chemical Pre-Oxidation And Aerobic Bioremediation Of Buried Mc252 Oil Across A Headlands Beach Profile, Olivia Bramlet

LSU Master's Theses

The release of MC252 crude oil following the Deepwater Horizon event has emphasized the need to investigate factors controlling the extent of contamination degradation in coastal environments. Dam structures created on Fourchon Beach, LA established conditions for PAH and n-alkane accumulation and burial along a vertical profile that persists today due to the anaerobic, often anoxic, and hypersaline conditions of the groundwater. The ability to remove the oxygen limitation present on in situ aerobic biodegradation of buried petroleum-based hydrocarbons in this environment was investigated through the coupled process of chemical oxidation and enhanced bioremediation using a proprietary formulation of activated …

Application Of The Hyman Model To Evaluate The Water And Salt Budgets In Three Mangrove Sites Along Shark River, Everglades, Cheng-Feng Tsai

LSU Master's Theses

Mangrove trees play an important role in the maintenance and sustainability of coastal wetlands due to their ability to adapt and survive in a wide range of saline and tidal conditions. Hydrologic processes (e.g., inundation frequency) and salinity are important regulators controlling the growth and productivity of mangrove forests. To quantify how changes in landscape-level hydrology will influence these regulators in mangrove forests, the hydrology model (HYMAN) was applied to three sites with distinct tidal forcings along the Shark River estuary in the Everglades National Park. HYMAN model uses mass balance equation to determine daily water and salt budgets as …

Development Of A Phosphorus Management Model To Address Filamentous Algae In A Shallow, Subtropical, Urban Hypereutrophic Lake, Jennifer Eileen Ruley

LSU Master's Theses

City Park Lake is a shallow, subtropical, urban hypereutrophic lake located in Baton Rouge, Louisiana. By the late 1970’s, this artificial lake had experienced extreme eutrophication and suffered from frequent algal blooms and fish kills. Restoration of City Park Lake occurred in 1983 and consisted of dredging nutrient-laden sediments and the rehabilitation of sewage pipelines. Pre- and post-restoration water quality monitoring programs have provided valuable information by which to gage the long-term success of the restoration work. Following the restoration effort, dramatic improvements were observed in the lake including lower nitrogen, phosphorus and chlorophyll-a concentrations, reduced frequencies in algal blooms …