Life Sciences Commons^™

Effects Of Large Wood Additions On Basal Resources, Macroinvertebrates, And Ecosystem Processes In The Narraguagus River, Maine, Val Watson

Electronic Theses and Dissertations

Ecological restoration is an increasingly common practice across ecosystems, and current practices aim to restore the biological and physical processes underlying ecosystem function, often for the sake of endangered higher-level consumers. Studies of restoration outcomes often report few or inconsistent ecological changes, and monitoring of restoration projects rarely measures ecological processes. Monitoring also usually measures outcomes at a single scale, despite the prevalence of scale- dependent phenomena across ecosystems. My thesis uses measurements of ecological processes to assess restoration response and evaluates responses across multiple scales. I focus here on a long-term large wood addition project on the Narraguagus River …

Developing Best Practices For The Propagation Of Spartina Alterniflora For Use In Salt Marsh Restortaion, Justin Hinson

Electronic Theses and Dissertations

Coastal salt marshes are valuable ecosystems under threat from climate change and sea level rise. Living shorelines offer a promising solution, often incorporating the foundational salt marsh species Spartina alterniflora due to its ability to tolerate natural stressors and maintain sediment stability. However, research suggests that seed-based propagation protocols should be developed on a local scale due to the genetic heterogeneity within and between S. alterniflora populations. Here, we attempt to contribute to the development of one such protocol for coastal Georgia S. alterniflora.

In Fall 2021, seeds were collected bi-monthly from four marshes of varying ocean proximity and …

Revegetating Salt-Impacted Soils In The Northern Great Plains, Abigail P. Blanchard

Electronic Theses and Dissertations

In the northern Great Plains (NGP), an estimated 10.6 million hectares of land are affected by naturally occurring salt-impacted soil. Naturally occurring salt impaction results when rainfall causes salts in parent material to move upward through the soil profile and remain in the root zone causing osmotic and ionic stress, negatively affecting seed imbibition, germination, and plant growth. Common methods to remediate saltimpacted soils were developed in the irrigated soils of the Southwestern U.S., are ineffective in the non-irrigated soils of the NGP, and can exacerbate the problem. Therefore, new methods to remediate salt-impacted soil in the NGP are needed. …

Characterization Of Sites For Native Herbaceous Understory Restoration In West Gulf Coast Longleaf Pine (Pinus Palustris) Savannas, Brooke Mccalip

Electronic Theses and Dissertations

Longleaf pine (Pinus palustris) savannas were once dominant in East Texas and parts of western and central Louisiana. Native understory species have since been removed or reduced by exotic plants that were introduced and from the reduction in the frequency of both wild and prescribed fires. A diverse layer of understory species can still be seen today, but not often in the historical savanna setting that is desirable in longleaf pine ecosystems. This project aimed to identify site characteristics associated with longleaf ecosystems that support a dense, herbaceous understory with little to no midstory cover.

A total of …

Breeding Bird Response To Post Oak Savanna Restoration Seven Years Post Management In Eastern Texas, Courtney Mcinnerney

Electronic Theses and Dissertations

Oak savannas were once an abundant vegetation type in the Midwestern United States that have now declined to <1% of their original distribution. Historically, natural disturbances such as periodic fire and grazing maintained oak savannas, but these have been reduced or eliminated, resulting in woody encroachment and subsequent habitat loss and degradation. In 2009-10, a baseline, pre-restoration study was completed to determine vegetation characteristics, breeding bird abundances, nest success, and nest site selection at the Gus Engeling Wildlife Management Area (GEWMA) in eastern Texas. The results showed a lack of savanna vegetation structure on degraded sites and few savanna or grassland obligate bird species. The goal of this study was to determine how breeding birds of oak savanna vegetation types in eastern Texas respond to restoration effects 7 years after initial management. Post-restoration surveys completed in 2016-17 showed a change in avian assemblages from a more woodland dominated community to grassland/savanna community. The presence and breeding of savanna obligate species dickcissel (Spiza americana) and lark sparrow (Chondestes grammacus) indicates that the restoration was successful. The presence of savanna species can be linked to the herbaceous vegetation that was restored to more closely resemble historic oak savanna structure and can quantify the success of restoration efforts.

Characterization Of Sites For Native Herbaceous Understory Restoration In West Gulf Coast Longleaf Pine (Pinus Palustris) Savannas, Brooke Mccalip

Electronic Theses and Dissertations

Longleaf pine (Pinus palustris) savannas were once dominant in East Texas and parts of western and central Louisiana. Native understory species have since been removed or reduced by exotic plants that were introduced and from the reduction in the frequency of both wild and prescribed fires. A diverse layer of understory species can still be seen today, but not often in the historical savanna setting that is desirable in longleaf pine ecosystems. This project aimed to identify site characteristics associated with longleaf ecosystems that support a dense, herbaceous understory with little to no midstory cover.

A total of …

The Ecology Of Land Managers In Riparian Restoration, Lisa Buie Clark

Electronic Theses and Dissertations

While previous studies in restoration ecology have focused on the efficacy of direct management actions, the driving forces on management decisions (e.g., managers' characteristics or attitudes, environmental conditions) and the indirect impacts on restoration outcomes from management decisions (such as whether to collaborate) are quantified here for the first time. As a case study, I used data from 244 sites across the riparian Southwest US where the invasive shrubby tree Tamarix sp. was removed using various different methods. I surveyed and interviewed the 45 land managers who were responsible for the removal projects to determine their characteristics, attitudes, and …

Herbivory Impacts On Growth And Survival Of Seedlings In Bottomland Hardwood Forest Restoration Sites In The Post Oak Savannah And Blackland Prairie Ecoregions Of Texas, Usa, Ryan J. Jacques

Electronic Theses and Dissertations

Interest in bottomland hardwood forests (BLHW) ecology and restoration has increased over the past 40 years. These communities aid in water quality improvement, streambank stabilization, and urban expansion mitigation. They also provide important habitat for many species of wildlife. Since the majority of remaining BLHW are degraded due to land fragmentation, restoration attempts are becoming commonplace within the Western Gulf Coastal Plain. However, restoration success has been mixed, with managers observing survival rates of <15% for desirable species due to various factors. Over two growing seasons, I investigated multiple factors that have potential to limit BLHW restoration success in East Texas. Specifically, I tested the impacts of herbivory by white-tailed deer (Odocoileus virginianus) and feral swine (Sus scrofa) on Nuttall oak (Quercus texana Buckley), Shumard oak (Q. shumardii Buckley), bur oak ( …

Long-Term Overstory Vegetation Responses To Prescribed Fire Management For Longleaf Pine At Big Thicket National Preserve, Deanna M. Boensch

Electronic Theses and Dissertations

At the western edge of the longleaf pine (Pinus palustris) range, federal land managers have burned the forests of Big Thicket National Preserve to bring back the structure and diversity of the longleaf pine forest. In the early 1990’s, a four year study was conducted by Rice University, and the National Park Service continued monitoring the study’s fire ecology research plots. After two decades of data collection, ordination was applied to species abundance data to examine changes in vegetation communities from a variety of prescribed fire treatments and controls. The vegetation data was separated by size class to include overstory, …

Community Ecology Of Soil Microbes In Southeast Usa Oak-Pine Woodlands, Ann L. Rasmussen

Electronic Theses and Dissertations

Soil microbial communities can have important effects on plant growth and plant community ecology; however, the relationships between trees and soil microbial communities are still relatively poorly understood. Here i examine several of these relationships. Chapter 1 examines how ecological restoration and environmental conditions affect the community composition and enzyme activities of Ectomycorrhizal fungi (emf). Chapter 2 considers whether host specificity in emf structures taxa occurrence on oaks and pines, and chapter 3 investigates how ash addition affects oak seedling growth and the soil bacterial community. I found that while wildfire lowered emf diversity, prescribed burning did not. Ectomycorrhizal root …

Native Grass And Forb Establishment In Post-Agricultural Soil, Courtney D. Hall

Electronic Theses and Dissertations

Restoration of degraded and abandoned agricultural land in arid and semiarid climates is a global problem. The erratic patterns of precipitation these lands experience makes restoration of a plant community difficult. Application of supplemental irrigation and inoculation with arbuscular mycorrhizal fungi (AMF) are two restoration techniques that have been suggested to overcome deficits in natural precipitation. The effects and the interactions of irrigation and seeding date on the ground cover of intended species and unintended exotic species were tested in a post-agricultural restoration experiment in south-central Colorado, USA. The greatest ground cover of intended species and lowest ground cover of …

The Effects Of Ecological Restoration On Soil Microbial Enzyme Activities And Leaf Litter Decomposition, Anthony Jason Rietl

Electronic Theses and Dissertations

This study examined the immediate effects of ecological restoration on soil enzyme activities and decomposition. The activities of five enzymes: phosphatase, ?-glucosidase, ?-N-acetylglucosadminidase (NAGase), phenol oxidase, and lignin-peroxidase were measured in both soils and on decomposing Quercus falcata leaf litter in unburned, burned, and burned and thinned plots in a mesic forest in northern Mississippi. Rates of decomposition were also assessed for Q. falcata leaf litter at each plot. The restoration treatments decreased phosphatase activity in relation to an increase in soil organic matter after the fire, and increased NAGase activity in relation to a decrease in leaf litter after …

Landcover Change And Population Dynamics Of Florida Scrub-Jays And Florida Grasshopper Sparrows, David Breininger

Electronic Theses and Dissertations

I confronted empirical habitat data (1994-2004) and population data (1988-2005) with ecological theory on habitat dynamics, recruitment, survival, and dispersal to develop predictive relationships between landcover variation and population dynamics. I focus on Florida Scrub-Jays, although one chapter presents a model for the potential influence of habitat restoration on viability of the Florida Grasshopper Sparrow. Both species are unique to Florida landscapes that are dominated by shrubs and grasses and maintained by frequent fires. Both species are declining, even in protected areas, despite their protected status. I mapped habitat for both species using grid polygon cells to quantify population potential …

Restoration Of Intertidal Oyster Reefs Affected By Intense Recreational Boating Activity In Mosquito Lagoon, Florida, Andrea Barber

Electronic Theses and Dissertations

In recent years, intertidal reefs of Crassostrea virginica (eastern oyster) along central Florida's east coast have suffered extensive losses due to wakes from recreational boats. These wakes have caused extensive shell movement and sediment resuspension which results in large piles of disarticulated shells along the seaward edges of reefs. Dead margins extend up to one meter above mean high water. The creation and enforcement of "no wake" zones in the area are unlikely. Thus, there is an urgent need for an alternative restoration strategy before these oyster reefs decline any further. The goal of this project was to develop a …

Effects Of A Shore Protection Project On Loggerhead And Green Turtle Nesting Activity And Reproduction In Brevard County, Florida, Kelly Brock

Electronic Theses and Dissertations

Marine turtle reproductive success is strongly correlated with the stability and quality of the nesting environment. Because females show fidelity to key nesting beaches, the management and physical characteristics of these beaches directly affect future generations of marine turtles and may be essential for the recovery of these threatened and endangered species. The impacts of beach restoration on loggerhead turtles (Caretta caretta) and on green turtles (Chelonia mydas) were investigated. Previous studies concerning beach nourishment projects have focused on loggerhead turtles. I compared data between nourished and non-nourished areas and between loggerhead and green turtles. I found, at one season …

Site Preparation Methods For Restoration Of Non-Native Pasturelands To Native Upland Habitat, Krisann Joie Kosel

Electronic Theses and Dissertations

The flatwoods ecosystem of Florida has been heavily depleted over time but remains one of the most important systems to many threatened and endangered species. Areas that have been converted into non-native pastures may be restored to provide not only this invaluable ecosystem but also restore connectivity of the surrounding ecosystems. The pasture areas on The Disney Wilderness Preserve in central Florida were surveyed, and a conceptual plan for restoration was written in 1996. That same year a pilot study was developed to assess five methods for removing non-native pasture grasses. The treatments studied were single herbicide, single disc, multiple …

Recruitment And Restoration Of The Oyster Crassostrea Virginica In Areas With Intense Boating Activity In Mosquito Lagoon, Florida, Lisa Michele Wall

Electronic Theses and Dissertations

Productivity, diversity and survival of estuaries are threatened by explosive coastal population growth and associated recreational activities. One major area of recreational growth has been the number of small pleasure craft motoring in shallow waters at high speeds. On the east coast of Central Florida in the Indian River Lagoon system, intense boating activity occurs year-round and intertidal reefs of the eastern oyster Crassostrea virginica with dead margins (piles of disarticulated shells) on their seaward edges are commonly found adjacent to major boating channels. The cause(s) of the dead margins is unclear. However, the disarticulated shells may be reducing reef …