Population and habitat assessment of the California, mountain, and Gambels quails in Californias changing landscape

California is an ecologically diverse state that supports California quail (Callipepla californica), Gambel’s quail (Callipepla gambelii), and mountain quail (Oreortyx pictus) populations. The state has experienced sweeping land use changes in the past half-century, leading to potential loss of habitat for these three species due to the impacts of urbanization, large-scale agriculture, and changing forest and rangeland management. Our goal was to determine the long-term population trends for the California, mountain, and Gambel’s quail in California and quantify how changes in land use and land cover impacted localized changes in relative abundance. We used the number of birds detected per route from the North American Breeding Bird Survey (BBS) to create five-year rolling average abundance maps. We established 30 – 50 random points within the geographic ranges of each species in California and extracted the number of birds detected per route from 1970 to 2017. We identified areas within the state that had declining, increasing, and no change in species’ abundances and compared road density (1992 - 2010), human population density (1990 - 2010), land use (1969-2017), and land cover (1986-2019). On the geographic-range scale in California, populations of all three quails did not experience long-term declines over the 45-year period of the BBS data. Areas where California quail abundances declined had 68% higher road densities and 130% higher human population densities in 2010, and 95% less bare ground and 48% less litter cover in 2019 than sites where they were increasing. Where mountain quail abundances were declining, irrigated land was 153% higher in 2017 but road density was 50% lower in 2010 than where they were increasing. Areas with increasing Gambel’s quail abundances had 119% lower human population densities and 91% lower road densities in 2010, and 47% less bare ground cover in 2019, than the area where abundances were decreasing. Our results indicate that these species can persist in a human-dominated landscape if sufficient quality habitat is available

Fine scale habitat use and movement of ocelots and bobcats

Ocelots (Leopardus pardalis) are a medium-sized wild felid native to South Texas. Ocelots are a species heavily dependent on vegetation cover and in South Texas depend on the availability of dense, woody and shrub cover. As the availability of these habitat types has declined due to urbanization and agriculture, populations of ocelots have declined, leading to the species being listed as federally endangered in the United States. As such, understanding the movement and habitat selection of ocelots is paramount to conserving local populations. Ocelots in Texas share their environment with two other ecologically similar species, the bobcat (Lynx rufus) and the coyote (Canis latrans). Understanding mechanisms of coexistence is essential for managing a target species. Advances in monitoring technology have provided the ability to obtain reliable, high-frequency data on wildlife. We monitored 8 ocelots (Leopardus pardalis), 13 bobcats (Lynx rufus), and 5 coyotes (Canis latrans) on the East Foundation’s El Sauz Ranch and the Yturria San Francisco Ranch in South Texas, USA, which were fitted with GPS collars that collected locations every 30 minutes. We examined fine-scale habitat selection and movement of ocelots and examined differences between competitor species to examine coexistence within the carnivore community. We compared spatial and temporal differences associated with differing behaviors between species using hidden Markov models. We then examine individual and population level selection of vegetation structure using step selection functions. We identified selection of thermal refuge by ocelots and bobcats during extreme heat and cold to examine how abiotic factors influenced interspecific competition. We compared habitat selection between all three species at the 2nd and 3rd order and examined avoidance of competitor species by ocelots across scales. We observed evidence of behaviorally mediated coexistence through spatial and temporal partitioning wherein ocelots and bobcats were active at night and rested in dense cover during the day while coyotes were active during the day and rested in more open areas at night. We observed fine-scale habitat partitioning and differences in selection for upper and lower story vegetation within and across species. We identified dense shrub and forest cover as essential thermal refuge for ocelots and bobcats, and show how abiotic factors can act to influence interspecific competition through niche partitioning. We observed differences in avoidance of competitor species across species and scales by ocelots, wherein bobcats were not avoided at any scale while coyotes were avoided at the 3rd order but not the 2nd. We provide a more comprehensive analysis of habitat selection by ocelots than previously available and compare selection between sympatric ocelots and bobcats, identifying several mechanisms of coexistence within this carnivore community

Mutagenesis of the gRICH70 gene promoter region to identify regulatory elements, and development of a GFP-based assay to detect effects of RICH proteins on neuronal plasticity

Nerve regeneration in the adult mammalian Central Nervous System (CNS) is severely compromised due to its intrinsic inability to regenerate after damage to axons. It is an unsolved puzzle for the modern biomedical scientist to find reliable therapies for patients with damage to nerve fibers of the CNS, though significant progress has been achieved in understanding the axon regeneration capabilities of neurons. Studies on the remodeling of neuronal cells at cellular & molecular levels can give insights about the molecules and genes that can trigger or enhance their plasticity. One such attempt from our lab to study the genes that help in neuronal regeneration is targeting the gene gRICH70 from goldfish and its homologous counterpart zRICH from zebrafish, which encode proteins that enhance neuronal plasticity. From previous work performed in our laboratory, a 0.42 Kbp region of the gRICH70 gene was identified that demonstrated strong promoter activity in PC12 pro-neuronal cells. The fragment contains a TATA box and several phylogenetically conserved sequence motifs that may harbor elements that regulate promoter activity. This study was geared to understand the role of these conserved sequences in gRICH70 gene regulation by performing Polymerase Chain Reaction (PCR) mutagenesis to delete specific conserved sequences and sub-clone the mutated fragments into a reporter plasmid (pGL3-Basic). The experiments performed demonstrated that the 260 bp region downstream of the TATA box harbor the required elements for expression in pro-neuronal cells. Two new reporter plasmids were also generated that target two highly conserved sequences in this region. The reporter plasmids should be useful to assess the presence of regulatory elements in these conserved sequences (by testing for promoter activity by luciferase assay). A second project was also initiated to develop an enhanced method to detect the effect of RICH proteins on structural neuronal plasticity. PC12 stable transfectant cells constitutively expressing EGFP-zRICH-WT fusion protein were generated that were easily detected by fluorescence microscopy for several weeks. These cells should be a very valuable tool to develop sensitive and simplified assay for detecting effects on neuritogenesis

Groundwater modeling of Kingsville Dome in-situ recovery (ISR) mine by Uranium Resources, Inc (URI)

Groundwater availability models provide scenarios of future conditions and can help local communities and water resource managers make decisions to protect the availability of clean water resources as needed. The area of interest in this study is the Kingsville Dome uranium mining site by Uranium Resources, Inc (URI) located in Kleberg County, South Texas about 35 miles southwest of the City of Corpus Christi. It has operated intermittently from 1988 to 2009. It has since been placed on standby due to insufficient uranium resources from the facility to warrant startup of operations again. The site has utilized the Evangeline Aquifer for its mining operations. In the event operations were to resume, this could potentially affect the aquifer due to the nature of in-situ recovery mining operations. The objective is to perform a hydraulic study using field data to create a new groundwater model using MODFLOW simulation software. The model can be used to investigate possible containment scenarios for hydraulic site control, whether it is site remediation or resumed in-situ recovery operations. To fit the data to a model requires obtaining field data from nearby wells. The hydraulic model can be used to identify a suitable injection and extraction well network and the pumping rates required that will achieve hydraulic control and prevent the spread of any possible chemical constituents left behind as a result of uranium mining operations

Design and assessment of agrivoltaics systems for energy cane farms in Texas

Due to climate change, natural disasters, and other unexpected events, such as the COVID-19 pandemic, farmers in Texas are facing the difficult task of maintaining a profit from their agriculture business. The concept of agrivoltaics creates a system that integrates renewable energy generation and agriculture with one another. This allows farmers to continue receiving income through their agricultural business while providing energy resilience through an environmentally friendly approach. This project evaluates the potential of implementing an agrivoltaic system using solar panels in an energy cane farm located in Weslaco, Texas. The biomass crop is of interest for an agrivoltaic system as it is low input and is drought resistant. Various databases and industry standards are implemented to optimize and design the agrivoltaics system. Data collected from the energy cane farm in Weslaco, Texas is used throughout the project and aid in creating a maintenance schedule for the agrivoltaics system. Additionally, software such as HomerPro, SolidWorks, and MATLAB are used throughout the process to aid the optimization efforts of the system. The final conceptual design increased the vertical mobility of the structure by integrating a pulley system. The sensitivity analysis of the agrivoltaics system in an energy cane farm showed that increasing shading density decreased the dry biomass yield, but the optimal shading density for maximizing energy production depended on the potential for selling surplus energy to the grid and the local cost of electricity

Effect of conservation management on grain sorghum-cotton cropping systems in a semi arid region

Conservation agriculture, including no-tillage (NT) and cover cropping, has not been as widely adopted in semi-arid regions, such as South Texas, to the same extent as areas of the United States that receive greater amounts of annual precipitation. The limited research demonstrating the effects of these practices on cropping systems is one of the reasons for the low implementation of conservation practices. For the first study, two years of data was collected from a grain sorghum (Sorghum bicolor (L.) Moench)-cotton (Gossypium hirsutum L.) dryland rotation that had been under no-till management for over 30 years at the Texas A&M AgriLife Research and Extension Center at Corpus Christi. This split-split-split plot experiment had two tillage treatments (conventional tillage [CT] or no-tillage [NT]), three winter cover crop treatments (fallow, mix of three species, or mix of six species), and two sorghum residue treatments (residue after harvest shredded or left standing). Soil gravimetric water concentration, target crop yield, penetrometer resistance, cover crop canopy cover and herbage mass was evaluated. The second study was conducted at the Texas A&M AgriLife Research – Beeville Station from 2011-2018. There were four winter cover crop treatments under strip-tillage management (‘Armadillo’ burr medic [Medicago polymorpha L.], ‘Bee Black’ black medic [M. lupulina L.], ‘Devine’ little burr medic [M. minima L.], or ‘Hykon’ rose clover [Trifolium hirtum All.]) with one control treatment (winter fallow and conventional tillage). Sorghum and cotton yield, soil fertility and other parameters, cover crop herbage mass, penetrometer resistance, and water infiltration data was measured throughout the duration of the study. Although there were limited consistent statistical differences among treatments in both studies, conservation agriculture practices did not reduce row crop yields. There is clear promise in the practicality of implementing one or more conservation agricultural practices in South Texas

Examining the relation between TELPAS scores and student achievement on the eighth-grade science STAAR test for students with limited English proficiency

This study explores the relationship between English Learners (ELs) in the Texas school system and their outcomes on the State of Texas Assessments of Academic Readiness (STAAR) tests and the Texas English Language Proficiency Assessment System (TELPAS). Schumann’s Acculturation Model and Krashen’s Input Hypothesis were used as theoretical groundwork to provide a thorough framework for exploring this association. To determine the different levels of acculturation among ELs, this study addressed the research questions posed using quantitative correlational research, specifically, the quantitative data of TELPAS and STAAR from a South Texas school district. The goal of this inquiry recognized patterns and trends within the data to determine if a substantial association exists between TELPAS scores and STAAR outcomes among ELs attending Texas schools. The study regularly found a modestly positive correlation between TELPAS scores and 8th-grade science STAAR scores. The results were statistically significant in all years, demonstrating a favorable association between a higher degree of English language proficiency and enhanced academic performance in the subject of science. Future research should investigate potential relationships and practical applications to develop effective techniques for assisting ELs. These observations can guide educational methods and regulations, ultimately enhancing student achievements and fostering fairness in education. These findings can guide instructional practices, resource allocation, and support systems for ELs. Furthermore, Schumann's Acculturation Model and Krashen's Input Hypothesis adds to the continuing conversation about language acquisition in diverse educational contexts by providing a new angle on the variables influencing ELs' academic success and language proficiency

Exploring the racialized educational experiences of minoritized graduate students in humanities degree programs

This phenomenological study sought to explore the racialized educational experiences of graduate students of color (GSOC) seeking degrees in humanities disciplines. While some research studies have focused on minority graduate student experiences, there has been less focus on minority graduate student experiences in the humanities. Utilizing Critical Race Theory, this investigation shed light on the lived experiences, inside and outside the classroom, of minoritized graduate students as they navigate their educational environments. Semi-structured interviews were conducted with a total of nine graduate students who were selected through purposive sampling to participate in the study. The findings support and extend the literature examining the educational experiences of graduate minority students in higher education. Implications and best practices on how faculty and educational administrators can support and better address the racialized encounters experienced during graduate study for minoritized students of color are discussed

Apparent permeability of liquid rich shales

The goal of this research is to present a new formulation expressing the apparent permeability of liquid rich shale strata based on pressure driven flow. Apparent permeability is important for the accurate prediction of production rates. For the first time we introduce an apparent permeability formulation to predict the volumetric flux of oil in liquid rich shale formations. Nanopores associated with the structure of shale formations introduce molecular slippage on the pore walls and break down the continuum no-slip flow assumption. The molecular slippage on the pore walls makes Darcy’s permeability inappropriate to determine the volumetric flux of oil in shale formations. In this research, a correction to the slippage phenomenon is made to properly model fluid flow in shale oil strata. The proposed permeability expression is validated with an existing set of experimental data. The derived formulation in this study shows that the apparent permeability of liquid rich shales increases with increased slip length; the slip length is defined as an extrapolated distance relative to the nanopore wall where the tangential velocity component vanishes. This novel permeability formulation is expressed in a compatible form with Darcy’s equation for ease of use in reservoir simulators. The results suggest that the proposed apparent permeability term provides a better prediction of oil volumetric flux compared to that given by the simple Darcy’s permeability

Understanding inconsistencies and implications of global surface water extent estimates

The abundant surface water storage systems in a landscape, including lakes, ponds, wetlands, and other small depressional storages, are “non-structural” natural features. These natural infrastructures provide a wide range of ecosystem services including maintenance of biodiversity, nutrient cycle regulation, sequestering carbon, water quality improvement, along with many socio-economic benefits. However, despite the tremendous importance of these surface water systems, these natural infrastructures are vulnerable to widespread conversion and destruction due to both natural and anthropogenic stressors. To adopt effective policy and management strategies for minimizing these conversions, and thereby improve the earth’s overall resilience to climate and anthropogenic disturbances, we must develop the capability to precisely and efficiently map surface water storages and their temporal dynamics. To this end, this thesis is the first study to (i) derive surface water occurrence and surface water extent estimates from a remotely sensed near-real time, temporally continuous, fine resolution land cover dataset (objective 1), and (ii) compare the consistency and conclusivity of the new estimates with existing prominent datasets of global surface water dynamics (objective 2). The outcomes are 10-m spatial resolution global surface water occurrence and permanent and seasonal surface water extent estimates providing novel insights into readily available freshwater resources. Next, this thesis hypothesizes that currently available GSWE datasets have many structural and spatial differences; there is a large variability in the way surface waterbody extents are perceived and estimated by different global datasets. This is tested by (iii) assessing and gathering details about the varying origins and approaches of different available GSWE datasets (objective 3), and (iv) quantifying the uncertainties in GSWE by mapping and estimating the variation in extent and count of waterbodies across the selected GSWE datasets (objective 4). Results suggest that the inconsistencies across GSWE datasets stem mainly from their underlying definition of surface waters, data format, and data sources and methods used for waterbody delineation. In summary, GSWE datasets are critical to understanding the availability and implications of global water resource variations, especially under a changing climate. However, without ensuring accuracy and consistency in today’s GSWE datasets, a stride towards sustainable water resources may not be meaningful. This work is an attempt to address these needs