Physical Sciences and Mathematics Commons^™

Exploring Soil Microbial Dynamics In Southern Appalachian Forests: A Systems Biology Approach To Prescribed Fire Impacts, Saad Abd Ar Rafie

Doctoral Dissertations

Prescribed fires in Southern Appalachian forests are vital in ecosystem management and wildfire risk mitigation. However, understanding the intricate dynamics between these fires, soil microbial communities, and overall ecosystem health remains challenging. This dissertation addresses this knowledge gap by exploring selected aspects of this complex relationship across three interconnected chapters.

The first chapter investigates the immediate effects of prescribed fires on soil microbial communities. It reveals subtle shifts in porewater chemistry and significant increases in microbial species richness. These findings offer valuable insights into the interplay between soil properties and microbial responses during the early stages following a prescribed fire. …

Integration Of Raman Spectroscopy And Python-Based Data Analysis For Advancing Neurobiological Research, Natalie E. Dunn

Doctoral Dissertations

The field of Raman spectroscopy continues to expand into biological applications due to its usefulness as a non-invasive technique that can be utilized qualitatively and quantitatively. However, the inherent weakness of Raman scattering leads to the need for each collected spectra to undergo a preprocessing step to remove noise, background drift, and cosmic rays. Biological research in particular needs large datasets due to the increased variability in samples. As datasets grow, the need to perform preprocessing on each individual spectra becomes daunting. Often, these steps are done by hand with the help of specialized software programs. Preprocessing can be accelerated …

Assessing The Effects Of The Spring Hunting Season Start Date On Wild Turkey Seasonal Productivity And Hunter Behavior, Joseph Quehl

Masters Theses

Many states throughout the Southeast have documented declines in wild turkey (Meleagris gallopavo) harvest and estimates of recruitment in poult-per-hen ratios. Wild turkey populations are driven by seasonal productivity, so the decline in these parameters may indicate a decline in the overall population. One hypothesis as to why we are seeing a reduction in productivity and a potential population decline is that the spring hunting season is disrupting the reproductive cycle by harvesting too many males before they have had the opportunity to breed, or by harvesting dominant males and disrupting the social hierarchy of the flock. Our …

The Impacts Of Tilled-In Biodegradable Plastic Mulch On Soil Microbial Communities, Corissa L. Martin

Masters Theses

Plastics mulch films are used in agriculture to help increase crop production by regulating soil water retention and soil temperature while also preventing weed growth. Despite these benefits, plastic mulches have led to higher levels of microplastic pollution as weathering occurs. In response to this issue, biodegradable plastic mulches (BDMs) have been introduced to help reduce plastic pollution as they are designed to be tilled into soil after each growing season to continue degradation. Degradation of these mulch films is dependent on climate and, in some areas, complete degradation can take years. Since some biodegradable plastic mulches are made of …

Multidimensional Investigation Of Tennessee’S Urban Forest, Jillian L. Gorrell

Doctoral Dissertations

Preserving existing trees in urban areas and properly cultivating urban forest conservation and management opportunities is valuable to the ever-growing urban environment and necessary for creating optimal experiences and educational tools to meet the needs of increasing urban populations. This dissertation contains studies investigating several facets of the urban forest, including environmental effects of deforestation and urbanization, tree equity, and urban forest facility management and accessibility. Community education and outreach at arboreta about the importance of the tree canopy can help promote environmental stewardship. A digital questionnaire was electronically distributed to representatives of arboreta certified through the Tennessee Division of …

Impact Of Cover Crop Species Diversity On Soil Nutrient Availability And Crop Productivity, Amanda Kramer

Masters Theses

Cover crops provide multiple environmental benefits that improve both soil and water quality; however, farmers only utilize them on approximately 5% of harvested U.S. cropland. Low adoption rates are attributed to yield impact concerns, seed and planting costs, and lack of advocacy. This study, which began in October 2019, assessed the effects of nitrogen rate and cover crop diversity on weed biomass, soil coverage, in-situ residue decomposition, soil nitrogen and phosphorus availability, and cash crop yield to better understand the costs and benefits of cover crop adoption at two locations in Tennessee (Milan and Spring Hill). Treatments were replicated 4 …

Winter Wheat Cover Crop Increased Subsoil Organic Carbon In A Long-Term Cotton Cropping System In Tennessee, Rounak Patra, Debasish Saha, Sindhu Jagdamma

Biosystems Engineering and Soil Science Publications and Other Works

Long-term cover-cropping and no-tillage practices can facilitate soil organic carbon (SOC) accumulation in agroecosystems for soil health and climate mitigation benefits. However, the contribution of these conservation management practices to SOC gain from the subsoil layers is not been extensively studied. To understand this knowledge gap, it is essential to determine the distribution of total SOC and SOC fractions in response to management practices across the soil profile. Therefore, this study was conducted by leveraging a 40-year replicated field experiment in a continuous cotton (Gossypium hirsutum) system. The management treatments examined included three cover crop treatments: 1) hairy vetch, HV …

Full Issue, Frank R. Thompson Iii

National Quail Symposium Proceedings

No abstract provided.

The Evolution Of Quail Research: Trends In Themes, Cognitive Extent, And Lexical Diversity, Fidel Hernández

National Quail Symposium Proceedings

Language is an interesting characteristic that is unique to humans. Language represents a method of human communication and is believed to reflect a person’s view of reality (Kramsch 2004). The words used by a person or a community provide insight into the ideas, concepts, and worldview held by people (Pennebaker et al. 2003). In science, publications represent a primary form of communication of ideas among scientists. Publications provide a historical record of a discipline and reflect the relative interest of a scientific community in particular concepts during a given era (Kim et al. 2018). Consequently, how word use in publications …

Effects Of Climate Change On Northern Bobwhite Nesting Chronology And Clutch Size, Justin A. Rectenwald, D. Clay Sisson, James A. Martin

National Quail Symposium Proceedings

Widespread changes to breeding bird phenology in response to climate change have been apparent in North America for several decades. While the impact of an earlier breeding season may be minimal by itself, changes in community-level interactions can be greatly influenced because of varying responses to climate change in different trophic levels. Climate change has been shown to alter the onset of breeding season and chick survival, and lead to population declines for game birds in high latitudes, at high elevations, and on the periphery of their range. The topic of climate change in relation to northern bobwhite (Colinus …

Examining A Habitat-Weather Threshold For Northern Bobwhite Populations In The Southwestern United States, John T. Edwards, Fidel Hernández, Andrea Montalvo, Masahiro Ohnishi

National Quail Symposium Proceedings

In semiarid portions of the northern bobwhite (Colinus virginianus; hereafter, bobwhite) geographic distribution, weather is a strong driver of interannual abundance. However, the strength of this relationship may depend on habitat amount. Given this habitat–weather dependence, there is likely to be a threshold value for habitat that determines how strongly a bobwhite population responds to weather. Our objective was to evaluate the relationship between habitat amount and the relative influence of weather on bobwhite abundance in Texas and Oklahoma, USA and determine a potential land-cover threshold value. We collected bobwhite abundance and land-cover data from the Breeding Bird …

Climate Impacts On North American Quail, Shelby M. Perry, Erin Moser, Jeffrey G. Whitt, Kelly S. Reyna

National Quail Symposium Proceedings

North America’s quail population trends are often linked to regional climate. Extreme climate events such as severe drought, hard freezes, or excessive winter precipitation can reduce quail populations by as much as 84%. Above-average spring and summer temperatures coincident with drought can reduce the laying season for quail by ≤60 days. Exposure of quail eggs to high temperatures during preincubation can initiate and alter embryonic development. Here, we review the impacts of extreme climate events and a changing climate on the survival, reproduction, and population trends of 6 North American quail species: California quail (Callipepla californica), Gambel’s quail …

Northern Bobwhite Response To Control Of Red Imported Fire Ants In The Gulf Coast Prairie Of Texas, Kelly M. Redmond, Eric D. Grahmann, Fidel Hernández, Leonard A. Brennan, Michael E. Morrow, Timothy Anderson

National Quail Symposium Proceedings

The population decline of northern bobwhite (Colinus virginianus; hereafter, bobwhite) on the Texas Gulf Coast Prairie, USA is largely attributed to habitat loss. However, red imported fire ants (Solenopsis invicta) occur throughout the region and are considered a possible contributing factor to the bobwhite decline. The objectives of our study were to determine the influence of red imported fire ants on bobwhites by comparing bobwhite nest success, survival, and density between sites treated with fire ant bait (treatment) and reference (control) sites. Our study was conducted on 3 private ranches in Goliad and Refugio counties, Texas. …

Northern Bobwhite And Fire: A Review And Synthesis, David A. Weber, Evan P. Tanner, Theron M. Terhune Ii, J. Morgan Varner, James A. Martin

National Quail Symposium Proceedings

Our understanding of the relationship between northern bobwhite (Colinus virginianus; hereafter, bobwhite) and fire began with Herbert Stoddard’s work in the early 20th century. Research on the topic has continued, but our application of fire is deeply rooted in Stoddard’s work, even as it has become evident that fire regimes must be adapted to variable environmental conditions that are evolving with a changing landscape and climate. A comprehensive review and synthesis of the literature on this topic would help formalize research advancements since Stoddard and identify knowledge gaps for future research. Results from experiments suggest fire creates favorable …

Bobwhite Response To Cattle Grazing In South Texas, Bradley K. Johnston, J. Alfonso Ortega-S., Leonard A. Brennan, Fidel Hernández, Humberto L. Perotto-Baldivieso

National Quail Symposium Proceedings

Range management practices to improve habitat for wildlife by reducing brush and increasing herbaceous plants, coupled with reduced stocking rates, can lead to dense stands of dominant grasses, such as four-flower trichloris (Trichloris pluriflora). This monoculture of trichloris creates dense vegetation unsuitable for northern bobwhite (Colinus virginianus; hereafter, bobwhite), reduces plant species diversity, and alters ecosystem functions. The objectives of this study are to 1) evaluate the effects of a proper cattle grazing regime to improve bobwhite habitat and 2) develop a management guide documenting how cattle grazing can be used as a tool to reduce …

Northern Bobwhite Response To Vegetation Management And Recovery In South Texas, Rachel A. Smith, Leonard A. Brennan, Humberto L. Perotto-Baldivieso, Fidel Hernández

National Quail Symposium Proceedings

The northern bobwhite (Colinus virginianus; hereafter, bobwhite) requires habitat structure and composition with grass cover for nesting, predator avoidance, and thermal refuge and forb cover for feeding on phytophagous arthropods and seeds. During the past 2 decades, many land managers with interest in promoting quail hunting opportunities have reduced or completely eliminated livestock across South Texas, USA, rangelands. Resting the land from grazing allows vegetation—especially grasses and forbs—to recover and thus provide nesting and foraging habitat for bobwhite and other birds. How bobwhite respond to postgrazing vegetation recovery is of keen interest to rangeland quail managers, but this …

Efficacy Of A Preemergence Herbicide Following Postemergence Control To Reduce Sericea Lespedeza In Old Fields Managed For Northern Bobwhite, Mark A. Turner, Bonner L. Powell, Craig A. Harper

National Quail Symposium Proceedings

Sericea lespedeza (Lespedeza cuneata; hereafter, sericea) is a nonnative forb that commonly invades sites managed for northern bobwhite (Colinus virginianus; hereafter, bobwhite). Sericea can reduce habitat quality for bobwhite as it outcompetes native plants that provide forage and cover. Bobwhite eat sericea seed, but seed are relatively indigestible and may limit nutrition intake and reduce the fecundity rate. Postemergence herbicides, including glyphosate, triclopyr, and fluroxypyr+triclopyr, control standing sericea, but do not provide preemergence control, which would increase long-term control because sericea annually produces large amounts of hard seed with high dormancy rates. Imazapic is labeled to …

A Simulation Model Of Sustained-Yield Harvest For Northern Bobwhite In South Texas, Joseph P. Sands, Stephen J. Demaso, Fidel Hernández, Leonard A. Brennan, Matthew J. Schnupp, Trent W. Teinert, Dale Rollins, Robert M. Perez

National Quail Symposium Proceedings

Recommended sustainable harvest rates for northern bobwhite (Colinus virginianus) vary greatly and range from 25% to 70% of the prehunt population. Because northern bobwhite populations have declined across their geographic range, determining sustainable harvest levels is critical for effective management. Our objectives were to use simulation modeling to identify sustainable rates of bobwhite harvest, probability of population persistence, and minimum viable population estimates. We also conducted a sensitivity analysis to evaluate the impacts of harvest on northern bobwhite populations in Texas, USA. We constructed a simulation model using Program STELLA 9.0 for a hypothetical northern bobwhite population on …

Spatial And Temporal Analyses Of Bobwhite Hunting Dynamics, D.Abraham Woodard, Leonard A. Brennan, Fidel Hernández, Humberto L. Perotto-Baldivieso, Neal Wilkins

National Quail Symposium Proceedings

A variety of factors influence the harvest of northern bobwhites (Colinus virginianus) and where that harvest occurs on a landscape. Many of these factors can be quantified and manipulated to distribute harvest pressure across time and space to meet desired spring densities. We collected spatial hunting metrics using global positioning system units on trucks and hunting dogs, along with detailed hunting logs from 211 quail hunts during the 2018–2019, 2019–2020, and 2020–2021 statewide hunting seasons in Jim Hogg County, Texas, USA. We found that hunting parties effectively covered 23.8 ± 0.3 hectares per hour, with hunts lasting 3.5 …

Evaluating The Harvest Rate Recommendation For Northern Bobwhites In South Texas, D. Abraham Woodard, Leonard A. Brennan, Fidel Hernández, Humberto L. Perotto-Baldivieso, Neal Wilkins, Andrea Montalvo

National Quail Symposium Proceedings

The current harvest rate recommendation for northern bobwhites (Colinus virginianus; hereafter, bobwhite) in South Texas, USA is 20% of the autumn population, including crippling loss. This recommendation is based on population simulations of empirical data. We completed the first field evaluation of the 20% harvest recommendation by comparing prehunting and posthunting bobwhite density estimates on a hunted and nonhunted site in South Texas during the 2018–2019, 2019–2020, and 2020–2021 statewide bobwhite hunting seasons in Jim Hogg County, Texas. We conducted line-transect distance sampling surveys on 4 occasions per year (early November, mid-December, late January, early March) from a …

Evaluation Of A Solar-Recharged Micro-Gps Datalogger For Northern Bobwhite In The Rolling Plains Of Texas, Byron R. Buckley, Rowdy A. White, C. Brad Dabbert

National Quail Symposium Proceedings

The use of Global Positioning Systems (GPS) transmitters on northern bobwhite (Colinus virginianus; hereafter, bobwhite) could increase our understanding of fine-scale movements and habitat use for a declining game bird species. We evaluated solar-recharged micro-GPS dataloggers to determine the effectiveness of the units on free-ranging bobwhite and we conducted a controlled experiment to determine the accuracy of the dataloggers under a variety of canopy cover. We deployed the micro-GPS dataloggers on 25 bobwhites between August 2016 and April 2017 across 4 different ranches in the Rolling Plains of West Texas, USA. Accuracy (± standard error) for the 8 …

Estimating Northern Bobwhite Density In Privately-Owned Forests Across The Southeast, John M. Yeiser, Bridgett Costanzo, Melissa Martin, Jessica Mcguire, Clayton Delancey, James A. Martin

National Quail Symposium Proceedings

Rigorous density estimates can inform management, conservation planning, and policy decisions. Northern bobwhite (Colinus virginianus; hereafter, bobwhite) populations are declining throughout their range, including the southeastern United States. Numerous private land conservation initiatives are underway to restore bobwhite populations in these areas, but baseline estimates of density spanning privately owned forests are sparse. This information gap makes it difficult to evaluate the population-level effects of these conservation programs or develop expectations for timelines to reach population targets. We sought to understand baseline densities across privately owned pine forests in the southeastern United States in areas targeted for bobwhite …

The Efficacy Of Video Cameras To Account For Northern Bobwhites Flushed, But Undetected During Aerial Surveys, Andrea Montalvo, Leonard A. Brennan, Michael L. Morrison, Eric D. Grahmann, Andrew N. Tri

National Quail Symposium Proceedings

Over the past 20 years, conventional distance sampling from a helicopter platform has been used to estimate northern bobwhite (Colinus virginianus; hereafter, bobwhite) density over large areas of rangeland vegetation. However, it has been speculated that aerial surveys can complicate the ability to meet the distance sampling assumption of detecting 100% of the target objects on the transect line due to the restricted observer view from the helicopter. We attempted to use video cameras to determine whether missed detections occurred and whether digital methods could improve the precision of bobwhite density estimates. Our objectives were to 1) determine …

Relationships Between Meteorological And Other Variables And Bobwhite Spring Call Counts, Jeffrey G. Whitt, Kelly S. Reyna

National Quail Symposium Proceedings

Accurate assessment of quail population trends is critical to the success of future conservation efforts. Financial considerations and time constraints often limit population trend estimates to indices, the most common of which are spring call counts and autumn covey counts. While all indices have limitations and caveats, spring call count data specifically possess variability that makes them ill-suited for detecting fine-scale trends. However, because spring call counts record calling males and are relatively easy to conduct, they are assumed to represent an index of breeding potential and produce the most data per unit cost. Here, we examine their variability, comparing …

Detection Rates Of Northern Bobwhite Coveys Using A Small Unmanned Aerial System-Mounted Thermal Camera, Megan E. Martin, Lori A. Hearon, Kristine O. Evans, Raymond B. Iglay, Jesse I. Morrison, Mark D. Mcconnell

National Quail Symposium Proceedings

The northern bobwhite (Colinus virginianus; hereafter, bobwhite) requires intensive monitoring to evaluate management efforts and determine harvest rates. However, traditional monitoring techniques (e.g., covey-call surveys) are labor-intensive and imprecise. Small unmanned aerial systems (sUASs) mounted with thermal cameras have demonstrated promise for monitoring multiple avian species and could provide a less intensive and more effective approach to monitoring bobwhite coveys, assuming coveys produce a recognizable heat signature. To assess sUAS monitoring, we evaluated the influence of bobwhite covey size (3, 6, and 12) and cover type (grass, shrub, and forest) on covey detectability by a sUAS equipped with …

Applying Multistate Mark-Recapture Models With State Uncertainty To Estimate Survival And Reproduction Of Quail, Rebekah E. Ruzicka

National Quail Symposium Proceedings

Obtaining unbiased estimates of vital rates and understanding how vital rates change in response to environmental stimuli are a continual pursuit of ecologists. Multistate mark-recapture (MSMR) models provide a flexible framework for evaluating dependent vital rates in a comprehensive analysis. For example, a bird must remain alive during breeding season to initiate a nest (i.e., transition from a nonbreeding to a breeding state); thus, the probability that a bird initiates a nest is dependent on the probability that it is still alive. Traditional MSMR models allow only for the estimation of survival, detection, and state transition parameters and depend on …

Exploring A Plant-Diversity Hypothesis To Explain Helminth Prevalence In Northern Bobwhite In Texas, John E. Herschberger, Shaelyn T. Rainey, Fidel Hernández, Kristyn G. Stewart, Andrea Montalvo, Lindsey K. Howard

National Quail Symposium Proceedings

Helminths, in particular eyeworms (Oxyspirura petrowi), may be a factor influencing northern bobwhite (Colinus virginianus; hereafter, bobwhite) populations in Texas, USA. Mean eyeworm prevalence in Texas appears to be greater in the Rolling Plains (55.1%) than the Rio Grande Plains (16.4%), a pattern generally attributed to possible differences in the occurrence of insects, the intermediate hosts of eyeworms. We explored an alternative hypothesis centered on plant diversity. Many plants possess phytochemicals with anthelmintic properties. Because wild animals suffering from parasitic infestations are capable of self-medicating via diet selection, organisms foraging in diverse communities may be expected …

Histopathological Analysis Of Quails In The Trans-Pecos Ecoregion Of Texas, Trey E. Johnson, Carlos E. Gonzalez, Dale Rollins, Josh G. Cross, Ryan S. Luna

National Quail Symposium Proceedings

Quail populations in Texas, USA, have declined over the past few decades due primarily to habitat loss. The role that parasites may play in such declines has been a recent topic of concern. To help address this question, we collected 12 scaled quail (Callipepla squamata), 8 Gambel’s quail (Callipepla gambelii), and 3 Montezuma quail (Cyrtonyx montezumae) from across the Trans-Pecos ecoregion of Texas via hunter harvest, funnel traps, and night netting. Quail samples were necropsied to determine the abundance of eyeworms (Oxyspirura petrowi). Histopathological analyses were conducted on quail eyeballs and periocular …

Analysis Of Predator Avoidance Behavior In California Valley Quail, Curt Vandenberg, Jeffrey G. Whitt, Kelly S. Reyna

National Quail Symposium Proceedings

Quail populations have been in decline across the United States, primarily due to habitat loss and climate. For remedy, landowners and game managers have attempted to restore populations by releasing captive-reared quail. These releases were largely unsuccessful, presumably due to high predation losses. Recently, there has been an increased interest in quail translocations, which tend to have lower mortality rates than captive-reared bird releases. Translocations are expensive and unpredictable, and require many person-hours; releasing captive-reared quail would be more efficient if the practice were successful. We compared predator avoidance behavior between captive-reared and wild-translocated California quail (Callipepla californica) …

Examination Of An Anecdotal “October Disappearance” Of Northern Bobwhite In The Rolling Plains Of Texas Through Demographic Data, Jessica A. Mehta, Rowdy A. White, Joshua B. Luft, C. Brad Dabbert

National Quail Symposium Proceedings

Landowners and wildlife managers in the Rolling Plains ecological region of Texas, USA often report encountering northern bobwhite (Colinus virginianus; hereafter, bobwhite) in summer but observe what they perceive as a decrease in quail by early to mid-fall. As most bobwhite research in the Rolling Plains is focused on either breeding season or overwinter survival and movement, researchers rarely record demographic data during this late summer and early fall period. We examined weekly survival probabilities of bobwhite (n = 244) across 7 sites in the western Rolling Plains Ecoregion from August to late November in 2016, 2017, …