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Full-Text Articles in Life Sciences

Evaluation Of Reproductive Phenology, Space Use, And Ecology Of The Eastern Wild Turkey (Meleagris Gallopavo Silvestris) In West-Central Louisiana, Chad Argabright Apr 2023

Evaluation Of Reproductive Phenology, Space Use, And Ecology Of The Eastern Wild Turkey (Meleagris Gallopavo Silvestris) In West-Central Louisiana, Chad Argabright

LSU Master's Theses

Nest site selection is a driving demographic force behind eastern wild turkey (Meleagris gallopavo silvestris) populations. However, previous research was likely not focused on the actual time of nest site selection, considering that nest site selection is likely only able to occur on the day of the first egg being laid. My objective was to determine if selection for any vegetation characteristics was occurring on the first day of laying. I estimated the path taken from the roost to the nest on the first day of egg laying (i.e., laying path) using GPS data collected from 164 unique …


Characterizing The Vegetation And Effects Of Climate Change On Parris Island, A Sea Island Ecosystem, Cody Hart Goodson Jan 2023

Characterizing The Vegetation And Effects Of Climate Change On Parris Island, A Sea Island Ecosystem, Cody Hart Goodson

Theses, Dissertations and Capstones

Coastal habitats provide many ecosystem services, protecting coastlines from storm surges and erosion, diminishing the effects of eutrophication, sequestering large amounts of carbon, and acting as vital wildlife habitat. Sea-level rise and increased storm surge intensity associated with climate change are increasingly disrupting coastal habitats. These disturbances can shift environmental gradients that drive the zonation of coastal vegetation types, driving habitat conversion. Monitoring coastal habitat conversion can improve our understanding of the dynamic effects of climate change on these landscapes. Therefore, our objectives for chapter 1 were to identify and describe the distributions of vegetation types present on Marine Corps …


Understanding The Role Of Small Mammals In Arctic Biogeochemical Cycling, Austin Roy May 2022

Understanding The Role Of Small Mammals In Arctic Biogeochemical Cycling, Austin Roy

Open Access Theses & Dissertations

Small mammals play an integral role in their ecosystems. This is especially true in northern ecosystems, where small mammals represent both top-down and bottom-up forces and can have strong effects on ecosystem function through affecting biogeochemical cycling. Despite these important effects, the role of small mammals in influencing biogeochemical cycling has been largely underappreciated in the understanding of arctic ecosystems, leading to a call to better understand how small mammal herbivores impact ecosystem processes including carbon cycling. The overarching goal of this dissertation is to assess how biogeochemical cycling is affected by small mammal herbivore presence, behavior, and population dynamics …


Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp Jan 2019

Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp

Dissertations, Master's Theses and Master's Reports

Boreal peatlands store approximately one third of the earth’s terrestrial carbon, locked away in currently waterlogged and frozen conditions. Peatlands of boreal and arctic ecosystems are affected increasingly by shifting hydrology caused by climate change. The consequences of these relatively rapid ecosystem changes on carbon cycling between the landscape and the atmosphere could provide an amplifying feedback to climate warming. Alternatively, the advancement of terrestrial vegetation into once waterlogged soils could uptake carbon as a sink. Previous work suggests that fens will become an increasingly dominant landscape feature in the boreal. However, studies investigating fens, their response to hydrologic and …


Vegetation Characteristics And Bird Communities Associated With Singing Painted Buntings In Northwest Arkansas, Lauren Kristina Thead Dec 2018

Vegetation Characteristics And Bird Communities Associated With Singing Painted Buntings In Northwest Arkansas, Lauren Kristina Thead

Graduate Theses and Dissertations

It has been shown that bird communities are affected by the species composition and physical structure of plant communities. Within avian communities, the bird species that are the most localized in distribution tend to be the most affected by habitat changes. My research analyzed plant and bird communities found with the Painted Bunting (Passerina ciris Linnaeus), a locally common but declining species throughout much of its range. First, I describe vegetation characteristics associated with singing male Painted Buntings in northwest Arkansas. I categorized field sites with singing male Painted Buntings as either managed for wildlife or unmanaged, based on land-use …


A Vegetation-Based Index Of Biotic Integrity For Wetlands Of Kentucky, Noelle Newman Smith Jan 2016

A Vegetation-Based Index Of Biotic Integrity For Wetlands Of Kentucky, Noelle Newman Smith

Online Theses and Dissertations

Wetland ecosystems have experienced severe declines across the United States, prompting efforts to assess the status of remaining wetlands and regulate their development. The Clean Water Act and the policy of “No Net Loss” have resulted in a system of permitting and mitigation for impacts to wetlands. Professional judgments of wetland quality are inherent in regulatory decisions related to preservation and mitigation, but many states, and until recently including Kentucky, have no standard, quantifiable means of assessing wetlands to guide the decision process. A rapid assessment method has recently been developed for Kentucky, but there is no intensive assessment method …


Synthesis Of Satellite Microwave Observations For Monitoring Global Land-Atmosphere Co2 Exchange, Lucas Alan Jones Jan 2016

Synthesis Of Satellite Microwave Observations For Monitoring Global Land-Atmosphere Co2 Exchange, Lucas Alan Jones

Graduate Student Theses, Dissertations, & Professional Papers

This dissertation describes the estimation, error quantification, and incorporation of land surface information from microwave satellite remote sensing for modeling global ecosystem land-atmosphere net CO2 exchange. Retrieval algorithms were developed for estimating soil moisture, surface water, surface temperature, and vegetation phenology from microwave imagery timeseries. Soil moisture retrievals were merged with model-based soil moisture estimates and incorporated into a light-use efficiency model for vegetation productivity coupled to a soil decomposition model. Results, including state and uncertainty estimates, were evaluated with a global eddy covariance flux tower network and other independent global model- and remote-sensing based products.


Modeling To Improve Vegetation-Based Wetland Biological Assessment, Robin C. Jones May 2014

Modeling To Improve Vegetation-Based Wetland Biological Assessment, Robin C. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To meet the requirements of the Clean Water Act (1972), natural resource managers need to be able to detect biological degradation in wetland ecosystems. Biological indices are commonly used by managers to assess wetland biological condition. The accuracy and precision of wetland condition assessments are directly related to the performance of these indices, and biological index performance is thought to be related to how well an index controls for the effects of environmental attributes on biological assemblages. Many plant-based biological indices control for environmental and biological variation through the use of classification schemes that are based on geographic location and …


International Polar Year (Ipy) Back To The Future (Btf): Changes In Arctic Ecosystem Structure Over Decadal Times Scales, Sandra Villarreal Jan 2013

International Polar Year (Ipy) Back To The Future (Btf): Changes In Arctic Ecosystem Structure Over Decadal Times Scales, Sandra Villarreal

Open Access Theses & Dissertations

Arctic vegetation communities are responding to climate warming through shifts in species composition and diversity but most observations have been made over relatively short time frames, and/or in association with experimental manipulations. Because vegetation plays a key role in regulating ecosystem productivity, nutrient cycling, surface energy budgets, and trophic interactions in the Arctic, there is a need to better understand shifts in tundra vegetation communities over decadal time scales. Understanding these shifts and their impact on ecosystem structure and function in the Arctic has important implications for predicting the future state of both the Arctic and the Earth System. Long …


Investigating Three Decades Of Vegetation Change In A Mojave Desert Mountain Range, Chris Lee Roberts May 2012

Investigating Three Decades Of Vegetation Change In A Mojave Desert Mountain Range, Chris Lee Roberts

UNLV Theses, Dissertations, Professional Papers, and Capstones

This project is a vegetation change study spanning 29 years in the Newberry Mountains of Southern Nevada. Long term monitoring data are crucial for understanding the effects of climate change on vegetation dynamics. Successful management intervention in vegetation change will require identification of early indicator plant species and their responses to climatic cues. This project is one of the oldest comparisons of resurveyed Mojave vegetation community plots with repeatable methodology and the longest survey interval reported for the southeastern Mojave Desert. 103 plots were relocated and resurveyed based on data methods in Jim Holland's thesis titled "A Vegetative Analysis of …


Habitat Characteristics Affecting Site Occupation In Wintering Henslow’S Sparrows At Mississippi Sandhill Crane National Wildlife Refuge, Mary E. Nicholson Dec 2011

Habitat Characteristics Affecting Site Occupation In Wintering Henslow’S Sparrows At Mississippi Sandhill Crane National Wildlife Refuge, Mary E. Nicholson

University of New Orleans Theses and Dissertations

Henslow’s sparrow (Ammodramus henslowii) winters in recently burned sites in pine savannas of the Southeastern United States. Previous studies have suggested that factors such as seed abundance and litter depth are important to wintering Henslow’s sparrows. My study asked how habitat variables including vegetation structure, seed abundance, and arthropod abundance predict Henslow’s sparrow site occupancy at Mississippi Sandhill Crane National Wildlife Refuge. In this study, Henslow’s sparrow more often occupied sites burned one growing season earlier than sites burned two growing seasons earlier, and did not occupy sites burned three or more growing seasons earlier. Data indicated that mass …


An Evaluation Of Population Estimators And Forage Availability And Nutritional Quality For White-Tailed Deer In Tennessee, Jared Tyler Beaver Dec 2011

An Evaluation Of Population Estimators And Forage Availability And Nutritional Quality For White-Tailed Deer In Tennessee, Jared Tyler Beaver

Masters Theses

Given the white-tailed deer’s (Odocoileus virginianus; deer) popularity and potentially negative impact on forested systems; Arnold Air Force Base (AAFB) in Tullahoma, Tennessee, USA has made minimizing negative deer impacts on biodiversity a priority. To address these management issues, I initiated a study on AAFB to investigate deer survey techniques and the effects of deer density on forage availability across vegetative communities.

Current use of infrared-triggered cameras (camera) for estimating deer populations does not provide a measure of precision critical for density estimation. I conducted a camera survey for deer in Wildlife Management Area (WMA) Units 1 and …


A Comparison Of Ecological Conditions And Relationships In An Altered Wetland And An Unaltered Wetland, Mark Kiyoshi Hurst Jan 2011

A Comparison Of Ecological Conditions And Relationships In An Altered Wetland And An Unaltered Wetland, Mark Kiyoshi Hurst

USF Tampa Graduate Theses and Dissertations

The purpose of the study is to identify and quantify the hydrologic and ecologic differences between two adjacent sections of Colt Creek; one section unaltered and one section altered by clearing and drainage. These differences were measured by monitoring water levels, groundcover vegetation in each of the two areas, and monitoring numbers and species of birds utilizing the two areas. Surface water levels were measured in three locations: in the historic Colt Creek flow way, in the ditch draining the creek, and in an adjacent wetland strand. In addition, a shallow monitor well in the creek was used to measure …


The Vascular Flora Of Greater San Quintín, Baja California, Mexico, Sula E. Vanderplank Jan 2010

The Vascular Flora Of Greater San Quintín, Baja California, Mexico, Sula E. Vanderplank

CGU Theses & Dissertations

The plants of San Quintín (Baja California, Mexico) were documented through intensive fieldwork and the collection of herbarium specimens to create a checklist of species. This region is home to a diverse flora with high levels of local endemism and many rare plants. The flora documented in this study was compared to historical records from the region and shows the impact of agriculture and urbanization on the plants, including several extirpated species. A study of the perennial vegetation using a 1 km grid provides species distribution data for 140 native species, which were assessed to highlight areas of significant species …


Modeling Potential Native Plant Species Distributions In Rich County, Utah, Kathryn A. Peterson May 2009

Modeling Potential Native Plant Species Distributions In Rich County, Utah, Kathryn A. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Georeferenced field data were used to develop logistic regression models of the geographic distribution of 38 frequently common plant species throughout Rich County, Utah, to assist in the future correlation of Natural Resources Conservation Service Ecological Site Descriptions to soil map units. Field data were collected primarily during the summer of 2007, and augmented with previously existing data collected in 2001 and 2006. Several abiotic parameters and Landsat Thematic Mapper imagery were used to stratify the study area into sampling units prior to the 2007 field season.

Models were initially evaluated using an independent dataset extracted from data collected by …


Evaluating Vascular Plant Composition And Species Richness On Horn Island, Mississippi, Using Passive And Active Remote Sensing In Conjunction With Ground Based Measurements, Kelly Lynn Lucas May 2008

Evaluating Vascular Plant Composition And Species Richness On Horn Island, Mississippi, Using Passive And Active Remote Sensing In Conjunction With Ground Based Measurements, Kelly Lynn Lucas

Dissertations

Barrier island vegetation is subjected to chronic abiotic stressors combined with periodic storm events that favor species adapted to harsh environments. These islands are the first landforms to be affected by changes in coastal subsidence and sea-level rise. Evaluating changes in vegetation is important for understanding the impact of global climate change on coastal environments.

This study assesses vegetation composition and plant species richness on Horn Island, Mississippi using ground data in conjunction with remotely sensed spectral and LIDAR data. The goals of this research are to: 1) classify and map vegetation composition on Horn Island using hyperspectral and LIDAR …


Mosquito Population Dynamics During The Establishment Phase Of A Constructed Desert Wetland, April Newman Jan 2002

Mosquito Population Dynamics During The Establishment Phase Of A Constructed Desert Wetland, April Newman

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Nature Preserve at the Clark County Wetlands Park is a constructed wetland that has the potential to produce new mosquito habitat. This thesis evaluates the potential for the development of a mosquito problem at the newly constructed wetland system by assessing the population dynamics of mosquitoes within the Nature Preserve. Based on data collected from May 2001 through January 2002, I describe fluctuations in mosquito genus and relative abundance during the first summer through winter period of wetland development.


A Walk On The Wild Side: Conceptual Master Plan And Vegetation Management Plan For The Ogden Nature Center, Beth G. Pyle May 1994

A Walk On The Wild Side: Conceptual Master Plan And Vegetation Management Plan For The Ogden Nature Center, Beth G. Pyle

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This report provides an introduction describing: 1) Ogden Nature Center site planning history; 2) background of the problem a) lack of a conceptual master plan which responds to current management objectives, b) lack of a vegetation management plan, and; 3) thesis objectives and methodology for the creation of conceptual master plan and vegetation management plan for the Ogden Nature Center. Chapter 2 presents a written discussion of the Ogden Nature Center site inventory drawings and site analysis. Chapter 3 delineates strategies for management of weedy vegetation including; a general discussion of management techniques, general criteria for the selection of weedy …


The Acarau Valley In Northeast Brazil: Vegetation, Soils And Land Use., Joao Stacishin De Queiroz May 1985

The Acarau Valley In Northeast Brazil: Vegetation, Soils And Land Use., Joao Stacishin De Queiroz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to describe and characterize the principal kinds of land in the mid-portion of the Acarau Valley, Ceara State, Northeast Brazil. The specific aims were: (1) to develop a specific-purpose soil classification; (2) to investigate vegetation-environment relationships; (3) to develop hypotheses about short-term vegetation dynamics; and (4) to evaluate the usefulness of computer processed multispectral-scanner (MSS) data for mapping rangeland resources in Northeast Brazil.

Fifty-one soil profiles were described and ocular estimates of vegetation cover by species were made at each subjectively selected site. Two Landsat scenes were used to assess the usefulness of MSS …


Diversity And Production Of Herbaceous Vegetation In A Northern Utah Subalpine Chronosequence, Gary A. Reese May 1981

Diversity And Production Of Herbaceous Vegetation In A Northern Utah Subalpine Chronosequence, Gary A. Reese

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Successional trends in herbaceous plant production and diversity were studied in an age sequence of sites, i.e. chronosequence, inferred to represent a meadow to aspen to fir to spruce-fir sere. Primary production was observed to decrease in a linear fashion with successional development. Three components of diversity; richness, heterogeneity, and equitability or evenness, each had low early successional values, reaching maximum diversity in mid-succession, and declining to intermediate levels with maturity. The magnitude of these trends varied greatly, depending on the methods used to determine plant dominance. Characteristics of various dominance indices and their applicability to this study were examined. …