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Patterns Of Distribution And Dispersion Of Silver Carp In An Oxbow Lake, Jordan Besson
Patterns Of Distribution And Dispersion Of Silver Carp In An Oxbow Lake, Jordan Besson
Theses and Dissertations
Oxbow lakes are highly productive waterbodies that host multiple life stages of many freshwater aquatic species. Oxbow lakes also provide habitat to Silver Carp (Hypophthalmichthys molitrix), which has enabled populations to grow and expand within the United States. Silver Carp are undesirable because they can compete for resources with native fishes. My goal was to identify patterns of distribution and dispersion of Silver Carp in Moon Lake, Mississippi, to assist and inform precise harvesting of fish. I implanted thirty-five adult Silver Carp with acoustic tags that I released into Moon Lake. I observed that Silver Carp were disproportionately …
The Impact Of Environmental Education Delivery Methods And Outreach Messaging On Attitudes, Interests, And Intended-Behavior Changes Toward Nature, Vanessa Elizabeth Hoffman
The Impact Of Environmental Education Delivery Methods And Outreach Messaging On Attitudes, Interests, And Intended-Behavior Changes Toward Nature, Vanessa Elizabeth Hoffman
Theses and Dissertations
Environmental education (EE) is important for environmental awareness and stewardship. Involving youth and adults in EE ensures current and future generations will conserve natural resources. This thesis explores impacts of delivery methods on participants’ environmental attitudes and behaviors toward nature through middle school classroom- and camp-based EE instruction, focus group interviews with rural minority youth, and adult responses to aquatic conservation outreach messaging. I observed no difference in environmental attitudes between online versus in-person delivery of EE lessons for middle-schoolers. Outdoor-based learning may be more impactful for EE than experiential, classroom-based learning. Focus group outcomes suggested youth EE programs should …
Seasonal Comparison On The Effectiveness Of Control Methods For Microstegium Vimineum In The North Carolina Piedmont, Casey Beam
Theses and Dissertations
Microstegium vimineum, or Japanese stilt grass, is an invasive species that readily outcompetes native vegetation and is of poor forage quality for wildlife. This species is widespread throughout the southeastern United States, including North Carolina. Much of this region is privately owned and there is a gap in the literature providing succinct information about the best methods of treatment, timing of treatment, and effects of treatment on native herbaceous plants in this region. In two parts, this study seeks to address this gap by employing treatments that are easily accessible to landowners at different times during the growing season and …
Effects Of Post-Fire Disturbance Responses Of Microstegium Vimineum On Native Hardwood Seedling Growth And Survival, Zachary A. Chandler
Effects Of Post-Fire Disturbance Responses Of Microstegium Vimineum On Native Hardwood Seedling Growth And Survival, Zachary A. Chandler
Theses and Dissertations
Invasions by alien understory plant species have gradually become a worldwide challenge in maintaining forest biodiversity and ecosystem productivity. Notably, Microstegium vimineum, a C4 grass native to Japan, has increased dominance in mixed deciduous hardwood forests of the southeastern United States, largely due to its shade tolerance and ability to spread through rhizomes. Microstegium vimineum also proliferates after prescribed fire, a common management tool used in the region to restore forests to desired conditions, and may compete with hardwood seedlings, hindering restoration efforts. Using two upland deciduous hardwood forest research sites in Marshall and Tate Counties, Mississippi, this study …
Oak Regeneration: Impacts Of Prescribed Fire And Invasive Species, Caleb Desmond Goldsmith
Oak Regeneration: Impacts Of Prescribed Fire And Invasive Species, Caleb Desmond Goldsmith
Theses and Dissertations
Across the central and eastern United States, upland oaks are experiencing regeneration complications. This thesis comprises two studies evaluating challenges in regenerating upland oaks. One study evaluates upland Quercus spp., Carya spp., and Acer rubrum L. response to prescribed fire and impacts on seedling growth and mortality. This study found prescribed fire promoted oak growth when canopy cover was < 77%. Oaks displayed lower percent mortality and higher resprout capacity after fire compared to red maple. The second study investigates impacts of Microstegium vimineum presence on Quercus alba L., Liriodendron tulipifera L., and Acer rubrum L. seedlings under different light and moisture environments. Microstegium vimineum presence decreased growth of both sweetgum and red maple; white oak was less impacted, likely because of its conservative growth strategy and high-water use efficiency. Oaks’ conservative growth strategy may offer more resiliency compared to its competitors in response to prescribed fire and Microstegium vimineum.
Evaluating The Influence Of Ecosystem Characteristics And Species Traits On Exotic Species Distributions, Adrián Lázaro-Lobo
Evaluating The Influence Of Ecosystem Characteristics And Species Traits On Exotic Species Distributions, Adrián Lázaro-Lobo
Theses and Dissertations
Natural dispersal mechanisms and biogeographical barriers have shaped species' native distributional ranges over millions of years. However, over the last few centuries, humans have dispersed species beyond their natural ranges. Those species that undergo explosive population growth and rapid expansion in the introduced region are considered as invasive because they have the potential to cause negative effects on desirable species and/or ecosystem services. In chapter II, I identified what ecosystem characteristics are more closely associated with successful establishment of exotic and native species, to have a better idea of where to concentrate our efforts and resources to prevent invasion events …
Sampling Techniques For Research And Management Of Cichlid Species In Lentic Systems, Jason Matthew Bies
Sampling Techniques For Research And Management Of Cichlid Species In Lentic Systems, Jason Matthew Bies
Theses and Dissertations
Introduced cichlid species are increasingly more common in tropical freshwater systems and expanding in range, often with negative consequences to receiving systems. To better understand, monitor, and manage these populations, improved cichlid sampling protocols are required. The goal of this study was to (1) evaluate diel electrofishing and gill netting sampling catch efficiency, and (2) compare two non-lethal methods for extracting stomach contents from Butterfly Peacock Bass Cichla ocellaris. This study suggests that electrofishing, particularly at night, may be a more appropriate gear for sampling cichlid species in the littoral zone of reservoirs, as gill nets were more time intensive, …
Beta Diversity Provides Evidence Of Niche Based Assembly In Temperate Forest Understory Assemblages Of Mississippi, David Steven Mason
Beta Diversity Provides Evidence Of Niche Based Assembly In Temperate Forest Understory Assemblages Of Mississippi, David Steven Mason
Theses and Dissertations
Assembly is a process that shapes the abundance and identity of species in a community. Niche and neutral theory explain assembly processes with mechanisms driven by either species differences, or functional equivalence and stochastic dispersal. In 2017 I sampled vegetation and environmental variables at 59 sites in the Noxubee National Wildlife Refuge and Tombigbee National Forest of Mississippi to explore forest understory community assembly. I developed and assessed a framework of predictions concerning general patterns and underlying mechanism. Evidence of dispersal limitation and functional equivalence were expected under neutral theory. Local environmental characteristics, surrounding landscape variables, and fire were significant …
Investigating Effectiveness Of Wild Pig Policy And Legislation In The U.S., Andrew Lane Smith
Investigating Effectiveness Of Wild Pig Policy And Legislation In The U.S., Andrew Lane Smith
Theses and Dissertations
The legislative procedures regarding wild pigs in the United States are expanding in scope and priority, however, the uniformity of legislation is entropic at best. Each state addresses the issues of wild pigs differently and treatment is based on a priority of resource concerns. An evaluation was conducted at the national level of federal, state, and local policy with regards to wild pig control. Additionally, successful and unsuccessful legislation is evaluated to determine commonalities in the social, economic, and ecological factors contributing to the success or failure of legislation. Information collected provides state legislatures with sample model legislation that can …
Recreational Firewood Movement As A Vector Of Non-Native Woodborers In Mississippi, Matthew John Thorn
Recreational Firewood Movement As A Vector Of Non-Native Woodborers In Mississippi, Matthew John Thorn
Theses and Dissertations
Recreational firewood collected from campers in Mississippi State Parks was investigated for factors associated with insect presence and their diversity. Insects were found in 20% of firewood and evidence of past feeding was found in 64.8%. Representatives of 35 families of insects were reared from collected firewood. These included representatives of Buprestidae, Cerambycidae, Curculionidae, Formicidae, and Rhinotermitidae. The effects of firewood age, moisture content, and source were also examined as effects on insect presence in firewood. At the same time, a survey of campers’ beliefs and attitudes about non-native woodborers was conducted. Exposure to public awareness campaigns had the strongest …
Assessment Of Chinese Privet (Ligustrum Sinense Lour.) Control Measures, And Selection Of Most Cost Effective Management Regimes, Fabio Jose Benez Secanho
Assessment Of Chinese Privet (Ligustrum Sinense Lour.) Control Measures, And Selection Of Most Cost Effective Management Regimes, Fabio Jose Benez Secanho
Theses and Dissertations
Chinese privet (Ligustrum sinense) is an invasive plant species in the United States (U.S.). This study utilized the most effective control measures found in the literature, and used financial analysis to identify the most cost effective management regimes to eradicate this species under different conditions. Management regimes were assessed using simulated scenarios created using six components, based on real parameters from the southern U.S.: infestation level, field coverage, stand density, herbicide application method, herbicide, and mechanical removal of privet. Financial impact on land expectation values (LEV) was analyzed and discussed for each simulated area conditions. Results suggest that the most …
Allelopathy In The Non-Native Macrophyte, Myriophyllum Spicatum And Its Influence On Trophic Dynamics In Aquatic Systems, Daniel J. Sullivan
Allelopathy In The Non-Native Macrophyte, Myriophyllum Spicatum And Its Influence On Trophic Dynamics In Aquatic Systems, Daniel J. Sullivan
Theses and Dissertations
Non-native macrophytes structurally impact aquatic assemblages, yet little is known regarding how they influence energy pathways in freshwater ecosystems. Allelopathy in Eurasian watermilfoil- Myriophyllum spicatum has been shown to target basal epiphytic organisms resulting in differences in assemblage structure of colonizing epiphyton between M. spicatum and native M. sibiricum. I conducted a growth chamber experiment to investigate the hypothesis that differences in assemblage structure of colonizing epiphyton between these two macrophytes influence trophic dynamics within aquatic systems. My data suggest M. spicatum produces higher concentrations of allelochemicals, resulting in a more diverse epiphytic assemblage compared to M. sibiricum. This could …
Biomass And Decomposition Dynamics Of Invasive Chinese Tallow (Triadica Sebifera) In The Southeastern United States, Allison M. Stoklosa
Biomass And Decomposition Dynamics Of Invasive Chinese Tallow (Triadica Sebifera) In The Southeastern United States, Allison M. Stoklosa
Theses and Dissertations
Recent and anticipated global change has focused concern on the role of forests in ecosystem functioning and carbon sequestration. Of key importance is identifying relevant factors that drive carbon and nutrient dynamics and the consequences of changes in these processes. Systems undergoing invasion by invasive woody species are particularly prone to changes. This study examined the branch and crown biomass and decay dynamics for the invasive Chinese tallow tree in Mississippi, USA as well as the influences of stand and site conditions on biomass modeling and arthropod contributions to fine woody debris decay. Coupling biomass and decay models presents a …
Dispersal And Management Of Invasive Aquatic Plants In Mississippi Waterways, Amanda Louise Fernandez
Dispersal And Management Of Invasive Aquatic Plants In Mississippi Waterways, Amanda Louise Fernandez
Theses and Dissertations
To understand the flow of water as a factor that influences aquatic vegetation communities and aquatic plant dispersal, custom-made Global Positioning System (GPS) drones were used to monitor the movement of water in Aliceville Lake, Columbus Lake, and Ross Barnett Reservoir, MS. In each reservoir, the drones drifted in the wind-generated surface current. Analysis of wind speeds suggests that a certain wind speed may be necessary to overcome gradient flow. Wind direction and wind speed should be incorporated in future spatial simulation models for aquatic plant dispersal and distribution. An herbicide evaluation on Cuban bulrush (Oxycaryum cubenese) was conducted to …
Mechanisms And Patterns Of Invasion In Macrophyte Communities, Jonathan Paul Fleming
Mechanisms And Patterns Of Invasion In Macrophyte Communities, Jonathan Paul Fleming
Theses and Dissertations
Aquatic plants (macrophytes) are important components of freshwater ecosystems and serve numerous purposes, physical and biological, that help to structure aquatic communities. Although macrophytes represent an essential component of stable aquatic communities, invasive macrophytes may negatively alter ecosystem properties. Non-native, invasive species have been identified as a major cause of biodiversity loss and the increasing prevalence of invasive species has prompted studies to help understand their impacts and to conserve biodiversity. Studying mechanisms of invasion also gives insight into how communities are structured and assembled. This study examined mechanisms that contribute to macrophyte invasion. First, I reviewed literature concerning mechanisms …
Multi-Scale Population Genetic Analysis Of Cogongrass (Imperata Cylindrica) In The Southeastern United States: Introduction History, Range Expansion, And Hybridization, Rima D. Lucardi
Theses and Dissertations
Biological invasions are a significant area of research due to perceived negative environmental and economic impacts. The study of biological invasions has identified three broad components involved in successful invasions: propagule pressure, abiotic and biotic conditions. Propagule pressure is the product of introduced propagules and the frequency of those introductions, and is considered a driver in all stages of invasion. Data to quantify propagule pressure is often unavailable, and therefore, this research approached genetic information to produce estimates of propagule pressure in the successful invasion of cogongrass (Imperata cylindrica) in the United States. The following research utilized molecular methodologies to …
Predicting The Potential Distributions Of Major Invasive Species Using Geospatial Models In Southern Forest Lands, Yuan Tan
Theses and Dissertations
Former researches provide evidence that invasive species could alter ecosystem’s components, threaten native species and cause economic losses in southern forest lands. The objective of the project is to explore significant driving factors and develop geospatial models for monitoring, predicting and mapping the extent and conditions of major invasive species. In the study area, 16 invasive species were classified into four groups: regionally spreading species, regionally establishing species, locally spreading species and regionally colonizing species by population size and spatial characteristics. According to local Moran’s I, spatial autocorrelation existed in 16 invasive species. Autologistic model and simultaneous autoregressive model were …
The Ecology Of Cactoblastis Cactorum (Berg) (Lepidoptera:Pyralidae) In Florida, Kristen Erica Sauby
The Ecology Of Cactoblastis Cactorum (Berg) (Lepidoptera:Pyralidae) In Florida, Kristen Erica Sauby
Theses and Dissertations
I used a theoretical model to determine the conditions under which Cactoblastis cactorum populations would be expected to experience positive population growth. Results from simulations suggest that host species richness, host quality, and the C. cactorum death rate interact to determine the probability of C. cactorum positive population growth. I also studied the influence of host diversity empirically. Cactoblastis cactorum prevalence was significantly higher when O. stricta was present in the community. Also, higher species richness within host assemblages led to a higher prevalence of infestation than in single-species host assemblages. Finally, I explored cooccurrence patterns of native cactuseeding insects …
Watching The Grass Grow: Effects Of Habitat Type, Patch Size, And Land Use On Cogongrass (Imperata Cylindrica (L.) Beauv.) Spread On Camp Shelby Training Site, Mississippi, Lisa Y. Yager
Theses and Dissertations
The purpose of this research was to increase understanding of ecology and control of cogongrass (Imperata cylindrica (L.) Beauv.) to assist with management of this invasive grass. To address different aspects of cogongrass management, I examined factors that affect spread of cogongrass, effects of cogongrass on native plant communities, and use of three native species to suppress cogongrass. Relative susceptibility of pine-bluestem and pine-shrub vegetation associations to vegetative encroachment and seed dispersal of cogongrass were evaluated. Vegetative encroachment into burned and unburned areas of these two vegetation associations also was measured. Effects of infestation size on vegetative growth of cogongrass …