Other Earth Sciences Commons^™

Wildfires: Vegetation Recovery And The Potential For Future Fires, Moses Okonkwo

LSU Master's Theses

Analysis of satellite imagery combined with Geographic Information Systems (GIS), often allows for observing the increasing changes in land cover dynamics. These changes are often on a macro scale buoyed by natural hazards such as wildfires. This study examines the vegetation recovery dynamics by using multispectral data and also gleaned insight in the applications of Hyperspectral satellite imagery in the study of vegetation dynamics. Both Landsat 8 Operational Land Imager (OLI) (multispectral) and the Earth-Observing One (EO-1) (hyperspectral) data are freely available; however the former has a limited spatial and temporal coverage. The relationship between vegetation recovery, elevation, aspect and …

Hydrometeorological Responses To Abrupt Land Surface Change Following Hurricane Michael, Shannon Alexis Nelson

LSU Master's Theses

While many of the destructive environmental conditions associated with tropical cyclones are well recognized, tropical cyclone-induced defoliation, a reduction in green leaves and mature vegetation, has been largely overlooked as a source of environmental stress following tropical cyclone passage. The land surface change associated with defoliation reduces evapotranspiration and shade, thus altering boundary layer moisture and energy fluxes that drive the local water cycle, for many months after tropical cyclone passage. Understanding the potential for any hydrometeorological impacts arising from such abrupt land surface change is important for guiding future post-hurricane preparedness and recovery planning in coastal communities.

This thesis …

Effect Of Channelized And Unchannelized Lateral Outflow On Three-Dimensional Flow Structure And Sediment Transport Mechanisms In A River Delta, Mohammad Kifayath Chowdhury

LSU Master's Theses

Spatial and temporal patterns in three-dimensional flow structure have been linked to channel morphology and processes in many environments, including river meander bends, confluences-diffluences, and bedrock canyons. However, there is not yet an understanding of how channelized and gradual, distributed lateral outflows that are often prevalent in deltaic distributary systems influence three-dimensional flow structure and sediment transport mechanisms. This thesis presents an analysis of 3D flow structure data collected from Wax Lake Delta, a naturally developing river-dominated delta in the northern Gulf of Mexico. Three hydrographic surveys were conducted using boat-mounted acoustic Doppler current profiler (ADCP) at two sites: an …

Suspended Sediment Transport Revealed By Patterns In Turbidity And Electrical Conductivity Curves In Three Cave Systems In Missouri, Usa., Caroline M. Mierzejewski

LSU Master's Theses

In cave streams, the movement of sediment as suspended and bed loads are linked to the occurrence of precipitation events on the surface. During precipitation events, the discharge of the streams in the basin increases. As those surface streams flow into cave streams via sinkholes or fissures, the discharge in cave streams increase. In addition to changes in discharge, the response of the surface and cave streams to precipitation include changes in turbidity and electrical conductivity of the stream water.

Changes in turbidity (Tu), electrical conductivity (EC), and discharge (Q) of water in the cave stream can be used to …

Monitoring Sediment Dynamics And Vegetation Competition Based On Micro-Topography And Terrestrial Lidar For Wetland Restoration, Xukai Zhang

LSU Doctoral Dissertations

With the ability to attenuate wave and limit erosion, coastal wetlands are important to protect shoreline for coastal communities. Micro-topography in coastal wetlands has a significant influence on hydrology, habitat variability and ecosystem functions. However, when mapping micro-topography by terrestrial LiDAR in coastal environments, the coverage of dense vegetation leads to a relatively low chance of laser penetration through the canopy to the ground. This dissertation proposes a rapid and flexible terrain mapping solution for the densely vegetated coastal environment by integrating crown structure from terrestrial LiDAR with terrain samples from GPS. The validated results in the study site demonstrate …

Effects Of Natural And Anthropogenic Forcing On Marsh Channel Evolution, Jeremiah Robinson

LSU Master's Theses

Wetlands have many ecological and physical properties that are essential for coastal communities. These ecosystems sustain local economies, provide essential habitats, are a source of numerous ecological and biological services, and protect coastal populations from storms. Of the many wetland types, salt marshes are among the most vulnerable to environmental changes. Salt marshes quickly respond to natural and human-driven perturbations and their high rate of loss in the last century is cause for concern.

In this project the rate of marsh loss driven by channel widening was measured through a comparative analysis of modern high resolution images and historic aerial …

How Dredge Pits Evolve Over Time: A Look At Their Geomorphologic Evolution And Infilling Processes, Patrick Robichaux

LSU Master's Theses

As coastal environments become more susceptible to land loss through accelerating sea level rise and subsidence, new restoration methods harnessing borrowed sediment are more valuable than ever. Mud-capped dredge pits (MCDPs) are a relatively new source of restoration-quality sediment that has only recently been utilized for beach and barrier island restorations in Louisiana. Because MCDPs have been in use for less than two decades in only a handful sites, little is understood about their evolution over decadal timescales. To improve our understanding of MCDPs after they are dredged, we have conducted a suite of geophysical surveys including bathymetry, sidescan sonar, …