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From Pixels To Plants: Remote Sensing Of California Invasive Plants, Kenneth Rangel May 2024

From Pixels To Plants: Remote Sensing Of California Invasive Plants, Kenneth Rangel

Master's Projects and Capstones

Invasive plants cause significant impacts to ecosystems, the economy, and human health. California has experienced significant plant invasions and is well suited to future invasion because of its Mediterranean climate and human disturbance. Eradication or control of invasive plant species requires a detailed understanding of their spatial distribution, which typically involves on the ground surveys that can be expensive or inconsistent. Remote sensing offers a potential alternative or supplement to in-person invasive plant mapping. This study performed a comparative analysis of 41 remote sensing studies that mapped the distribution of California invasive plants. I found that while high spectral resolution …


Automated Tree Mortality Detection Using Ubiquitously Available Public Data, Michael T. Huggins Mar 2024

Automated Tree Mortality Detection Using Ubiquitously Available Public Data, Michael T. Huggins

Master's Theses

Understanding the dynamic interplay between fire severity, topography, and tree mortality, is crucial for predicting future forest dynamics and enhancing resilience against climate change-induced wildfire regimes. This thesis develops a multi-sensor approach for automated estimation of tree mortality, then applies it to examine trends in tree mortality over a six-year period across a fire affected study site in the Trinity River basin in Northern California. The Random Forest model uses publicly available USGS 3D Elevation Program Lidar (3DEP) and NAIP imagery as inputs and is likely to be easily adaptable to other landscapes. The model had a Receiver Operating Characteristic …


Environmental Biology Masters Capstone, Antonio Gonzalez-Pita Jan 2024

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

Human wildlife interactions (HWI) pose a complex challenge for wildlife managers. Human encroachment into wildlife habitat and the growing number of outdoor recreationists are increasing the frequency of contact and conflict, especially in regions such as the Front Range of Colorado. Geographic information systems (GIS), which use a combination of remote sensing and environmental survey data, allow for predictive spatial analyses of where human wildlife interactions are likely to occur. I used publicly reported observations of moose to create spatial predictive maps in a species distribution model framework. Slope and elevation were shown to be the strongest predictors of HWI, …


Habitat And Demography Of The Ozark Chinquapin (Castanea Ozarkensis) At Roaring River State Park In Barry County, Missouri, Danielle Evilsizor Dec 2023

Habitat And Demography Of The Ozark Chinquapin (Castanea Ozarkensis) At Roaring River State Park In Barry County, Missouri, Danielle Evilsizor

Electronic Theses & Dissertations

The Ozark chinquapin, Castanea ozarkensis Ashe, is a chestnut tree with a range concentrated in the Interior Highlands of North America. Like other North American members of Castanea, it was reduced from an overstory tree to an understory shrub by the invasive chestnut blight fungus (Cryphonectria parasitica [Murrill] M.E. Barr) during the early 20th century. However, relatively little is known about the habitat of this species or its health and reproductive capability post chestnut blight. Chapter one of this study analyzed the habitat of this species through a random forest species distribution model (SDM) to predict where …


Patterns And Drivers Of Wiregrass Gap Longleaf Pine (Pinus Palustris Mill.) Woodland Succession As Part Of Restoration Efforts, Armin Weise Aug 2023

Patterns And Drivers Of Wiregrass Gap Longleaf Pine (Pinus Palustris Mill.) Woodland Succession As Part Of Restoration Efforts, Armin Weise

All Theses

Longleaf Pine (Pinus palustris) communities are widespread throughout the Southeastern United States with a dominant understory vegetation of wiregrass (Aristida spp.) in most of its range. A small area in central South Carolina that is naturally free of wiregrass is called the “Wiregrass Gap”. Here, the understory vegetation is dominated by bluestems grasses (Andropogon spp. and Schizachyrium spp.) which drive the disturbance regime of frequent low-intensity fire. The successful establishment of these grasses is key for longleaf pine woodland restoration efforts in this region, but few resources detail the ecological drivers at play that enable successful restoration in these longleaf …


Drought Tolerance In Native And Invasive Populations Of The Centaurea Jacea Hybrid Complex, Zoe Portlas Jan 2022

Drought Tolerance In Native And Invasive Populations Of The Centaurea Jacea Hybrid Complex, Zoe Portlas

Graduate College Dissertations and Theses

Introduced plants face many ecological and evolutionary challenges when establishing in a new range, such as strong abiotic stressors and potentially novel selective environments. One such abiotic stress is water availability, which is a strong selective force shaping physiological and phenological traits that enable plants to tolerate or avoid drought stress. Despite the challenges of establishing in a new range, thousands of species have become invasive in recent centuries. Two hypotheses that may explain how a species is able to withstand stress in its introduced range are preadaptation, which posits that species are adapted to similar environments in their native …


Floodplain Forest Regeneration Dynamics In The Lower Mississippi River Alluvial Valley, Whitney Anne Kroschel Jul 2020

Floodplain Forest Regeneration Dynamics In The Lower Mississippi River Alluvial Valley, Whitney Anne Kroschel

LSU Doctoral Dissertations

Floodplain forest species diversity is driven, in part, by variation in disturbance regime. Flood patterns create heterogeneity in microsite quality from small differences in elevation across a floodplain which, in turn, influence flood timing and duration. Differences in species’ regeneration niches in relation to hydrologic patterns can account for long-term coexistence of various species. In the past century floodplain forests have exhibited a wide range of changes in stand development and species composition as a result of altered hydrology in rivers and floodplains. I evaluated the role of regeneration in floodplain forest systems of the Lower Mississippi River Alluvial Valley …


Vegetative Community And Health Assessment Of A Constructed Juncus-Dominated Salt Marsh In The Northern Gulf Of Mexico, Nickolas R. Murphy May 2020

Vegetative Community And Health Assessment Of A Constructed Juncus-Dominated Salt Marsh In The Northern Gulf Of Mexico, Nickolas R. Murphy

Master's Theses

Deer Island is a coastal habitat which provides a buffer from storm and flood damage as well as shore-line stabilization to the mainland of Biloxi, Mississippi. A third of the land has been lost since 1850, largely driven by tropical storm and hurricane impacts as well as sea level rise. The United States Army Corps of Engineers and Mississippi Department of Marine Resources have targeted the shores of the island as sites for restoration using beneficial use dredged material, and two sites of differing age have since been planted with Spartina alterniflora, Juncus roemerianus, Uniola paniculata, S. patens, and Panicum …


Effects Of Water Table Depth And Edaphic Characteristics On Plant Diversity In A Southern Mississippi Pitcher Plant Bog, Patrick Kirby Dec 2019

Effects Of Water Table Depth And Edaphic Characteristics On Plant Diversity In A Southern Mississippi Pitcher Plant Bog, Patrick Kirby

Master's Theses

This study examined the effects that water table depth and soil characteristics have on plant species richness and species composition within pitcher plant bogs across seasons. Eight piezometers were installed at random distances to monitor long-term water table depth and pressure fluctuations along a ~710-meter line transect traversing upland and bog habitats. Vegetation sampling quadrats (n=128) were set up near each piezometer. Cover data and water table depths were collected in spring and late summer. Soil samples collected from each treatment group were used to obtain soil texture and nutrient data. The summer collection period yielded a total gdiversity of …


Competition Or Facilitation: Examination Of Interactions Between Endangered Sida Hermaphrodita And Invasive Phragmites Australis, Samantha N. Mulholland Jan 2019

Competition Or Facilitation: Examination Of Interactions Between Endangered Sida Hermaphrodita And Invasive Phragmites Australis, Samantha N. Mulholland

Theses and Dissertations (Comprehensive)

Virginia Mallow (Sida hermaphrodita) is a perennial herb of the Malvaceae family that is native to riparian habitats in northeastern North America. Throughout most of its geographical distribution however, it is considered threatened and only two populations are known from Canada. The biology and ecology of S. hermaphrodita are still poorly understood and although few studies have been performed to determine the factors that contribute to the species rarity, it is considered threatened potentially due to the loss of habitat caused by exotic European Common reed (Phragmites australis subsp. australis) invasion. Allelopathic and phytotoxic conditioning of …


Where Are All Of Arkansas' Chinquapins? An Ecological Assessment Of Castanea Throughout The State, Logan Pierce Estes Dec 2018

Where Are All Of Arkansas' Chinquapins? An Ecological Assessment Of Castanea Throughout The State, Logan Pierce Estes

Graduate Theses and Dissertations

Around the turn of the twentieth-century, the chestnut blight fungus (Cryphonectria parasitica) was accidentally introduced into North America. This strong pathogen, which specializes on trees of the genus Castanea, spread rapidly and within half a century had nearly extirpated North America’s Castanea natives from their ranges. During this catastrophe, the American chestnut (Castanea dentata) garnered much of the scientific attention, pushing the other Castanea natives – the chinquapins – to the wayside. More than a century following the spread of the blight, little research into the ecology of North America’s chinquapins had been performed, leaving these trees significantly underrepresented. The …


Investigating The Ecology Of A Rare Species On St. John, Usvi: Reintroducing Solanum Conocarpum In Light Of Climate Change, Cecilia Rogers Jan 2018

Investigating The Ecology Of A Rare Species On St. John, Usvi: Reintroducing Solanum Conocarpum In Light Of Climate Change, Cecilia Rogers

Senior Honors Projects, 2010-2019

Approximately two thirds of St. John is National Park territory. However, the land has been threatened with tourism and development, greatly impacting island biodiversity. One species that may become extinct due to this degradation is Solanum conocarpum. S. conocarpum is a rare shrub, endemic to the dry tropical forests of St. John, USVI. This plant is a species of conservation concern and is one of very few native and endemic plants on this island. Very little is known about the ecology and reproduction of S. conocarpum. Most plants are found on the southern half of the island. Recent observations …


Drivers Of Post-Fire Vascular Plant Regeneration In The Conifer-Dominated Boreal Forest Of Southern Northwest Territories, Alison White Jan 2018

Drivers Of Post-Fire Vascular Plant Regeneration In The Conifer-Dominated Boreal Forest Of Southern Northwest Territories, Alison White

Theses and Dissertations (Comprehensive)

In recent years, climate warming has led to an increase in the severity and frequency of naturally occurring fires in boreal ecosystems globally. In 2014, an unprecedented 3.4 million hectares of boreal forest burned in the Northwest Territories (NWT). While much research has focused on post-fire succession of serotinous tree species such as Picea mariana (black spruce) and Pinus banksiana (jack pine), the understory community of vascular plants play an important role in ecosystem functioning but less is known about the response of this component of the system to changing fire regimes. Regeneration strategies such as the ability to resprout …


Phenotypic Plasticity Of Native And Invasive Cool-Season Grasses In Response To Frequency Of Moisture Availability, Ming-Yu Stephens Jan 2017

Phenotypic Plasticity Of Native And Invasive Cool-Season Grasses In Response To Frequency Of Moisture Availability, Ming-Yu Stephens

Electronic Theses and Dissertations

Phenotypic plasticity, the ability of an individual to alter its growth in response to environmental conditions, is an attribute that is considered a likely invader attribute, as it provides the opportunity to expand its ecological niche breadth. Adaptive phenotypic plasticity can affect not only the ability to establish in a new environment, but also the ability to outperform the existing vegetation over time. Bromus inermis (smooth brome) and Poa pratensis (Kentucky bluegrass) are invasive species in tall- and mixed-grass prairie ecosystems. The objectives of this two-part study were to quantify the adaptive plasticity of biomass accumulation and tiller production in …


An Assessment Of How Plant And Mycorrhizal Communities Have Been Affected Along A Mine-Impacted Watershed In The Northwest Territories, Kevin Maccoll Jan 2017

An Assessment Of How Plant And Mycorrhizal Communities Have Been Affected Along A Mine-Impacted Watershed In The Northwest Territories, Kevin Maccoll

Theses and Dissertations (Comprehensive)

Giant Mine is an inactive gold mine located nine kilometers north of Yellowknife, Northwest Territories. Giant Mine has been the source of arsenic trioxide for the Baker Creek watershed since it opened over 60 years ago. Although arsenic levels in the creek are above the limits considered to be biologically relevant, there is no concrete evidence that plants and mycorrhizae have actually been affected. This study provides an initial assessment of the impacts mining activity at Giant Mine has had on plants and mycorrhizae in the Baker Creek watershed. Nine sites were sampled around Giant Mine: five sites downstream from …


Mechanisms Of Native Shrub Encroachment On A Virginia Barrier Island, Joseph Thompson Jan 2016

Mechanisms Of Native Shrub Encroachment On A Virginia Barrier Island, Joseph Thompson

Theses and Dissertations

Species composition, temperature, soil nutrients, and leaf area index (LAI) were recorded across three encroaching Morella cerifera thicket edges and three free- standing shrubs on Hog Island, Virginia to characterize the effect of shrub thickets on the plant community and microclimate. Electron transport rate (ETR) was taken on shrub leaves to determine if microclimate benefits M. cerifera physiology. Species richness was lowest inside shrub thickets. Soil water content and LAI were higher in shrub thickets compared to grassland. Soil organic matter, N, and C were higher inside shrub thickets. Summer and fall maximum temperatures were more moderate in shrub thickets …


Dispersal: A Multidisciplinary Investigation Of Plant Life, Alexandra E. Arzt Jan 2015

Dispersal: A Multidisciplinary Investigation Of Plant Life, Alexandra E. Arzt

Theses and Dissertations

Using plants as a basis for exploring the interstices between the human and nonhuman, this thesis investigates ideas of awareness, intelligence, deep time, animism, and the fluctuating human perception of the agency of Nature. It outlines environmental art practices since the 1950s involving vegetal life. In addition, the paper provides a critical analysis of plant perception of Jakob von Uexküll’s work and theories of vital materialism and “critical plant studies” while noting recent studies in plant neurobiology. In my work, plants become active participants via their movement, seeding, and smell. This study takes the form of imitation, purposeful symbiosis, anthropomorphism, …


The Riparian Vegetation Of Swauk Creek, Edward L. Schneider Aug 1971

The Riparian Vegetation Of Swauk Creek, Edward L. Schneider

All Master's Theses

An investigation was made to document the structure and composition of the flora along Swauk Creek, a riparian transect into Central Washington's Cascade Range. Distributions of the major species are discussed and a key has been constructed to facilitate identification of the riparian associations.