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Effects Of Elevated Temperature On Gonadal Functions, Cellular Apoptosis, And Oxidative Stress In Atlantic Sea Urchin (Arbacia Punctulata), Jackson B. Johnstone

Theses and Dissertations

Increasing surface sea water temperatures effect on growth, reproduction and development in marine organisms. Sea urchins are excellent indicator species and ideal model organisms to focus on. In this study, I tested the effect of higher temperatures on reproductive functions, heat shock protein (HSP, a chaperone protein produced by cells in response to heat stress) and nitrotyrosine protein (NTP, an indicator of reactive nitrogen species, RNS) expressions, cellular apoptosis, and ceolomic fluid (CF, a body fluid which regulates important physiological processes) conditions in Atlantic sea urchin at three different temperatures. Ten sea urchins were placed in each of six aquariums …

A Snapshot Of The Age, Growth, And Reproductive Status Of Gray Triggerfish (Balistes Capriscus, Gmelin 1789) On Three Artificial Reefs In The Northwest Gulf Of Mexico, Adam M. Lee

Theses and Dissertations

Age, growth, and reproductive status of gray triggerfish (Balistes capriscus) were identified from 2015-2016 on artificial reefs in the northwest Gulf of Mexico. Individuals ranged from 232-432 mm fork length with and a mean fork length of 319 mm. Individuals from age 0.2 to 5.2 yrs were observed with a weight to length relationship of Wg = 1.1 x -104 x FL2.7 (r2 = 0.94, n = 112), where FL = fork length (mm) and Wg = weight (g). A von Bertalanffy growth equation of Lt = 326(1 - e - 0.9 (t + 1.71)) was calculated irrespective …

Effects Of Global Warming On Gonadal Functions, Cellular Apoptosis, And Oxidative Stress In The American Oyster, Sarah B. Nash

Theses and Dissertations

Global warming due to climate change is predicted to intensify the heat stress in marine and coastal organisms, affecting their development, growth and reproductive functions. In this study. I analyzed gonadal development, heat shock protein 70 (HSP70), nitrotyrosine protein (NTP), dinitrophenyl (DNP) expressions, cellular apoptosis, and coelomic fluid (CF) conditions in American oyster. Oysters were placed in six aquariums and exposed to control (24°C), medium (28°C), and high (32°C) temperatures for one week. Higher temperature significantly decreased the number of eggs and sperm. CF protein concentrations also declined compared to control. In contrast, CF pH and HSP70 expression in gonad …

Impacts Of Habitat Attributes And Community Gardens On Urban Bird Communities, Samuel Glenn Ortiz

Theses and Dissertations

The Rio Grande Valley of Southern Texas is a major agricultural region yet has some of the highest hunger rates in the USA. Urbanization and agriculture affect biodiversity, which is well studied, but little is known about how agriculture affects biodiversity in urban areas. We investigated how different urban attributes, including those related to urban farming, impact bird communities in Brownsville and Harlingen, TX, and compared sites that have community gardens to those that do not. To study three key urban habitat characteristics, we identified sites that exhibited all possible combinations of these factors, quantified land cover classes related to …

Measuring Connective Capacity Throughout The Gulf Of Mexico Fishery Management Network, Anthony Rocha Lima

Theses and Dissertations

The Gulf of Mexico provides substantial resources along its 1,680-mile coastline, spanning 5 U.S. states and providing millions of pounds of seafood and hundreds of millions in revenue annually. Continued success of the fishery relies on the ability of a large, complex, multiagency network to find the best solutions to balance the needs of humans, as well as ensure long-term sustainability. Organizations with varying objectives require effective communication when addressing intricate ecosystem-based management topics such as endangered species and regional economies.

To better understand the connectivity within the Gulf fishery management network, an IRB reviewed survey was dispersed to the …

Longitudinal And Temporal Comparison Of Beach Sand On The Rio Grande Delta System, Samantha B. Moore

Theses and Dissertations

The Rio Grande is the 5th longest river in North America and defines a significant extent of the United States-Mexico border. It extends for 2830 km from its headwaters in the Rocky Mountains of Colorado to the Gulf of Mexico. The Rio Grande is fed by streams from the Sangre de Cristo Mountains, the Rio Conchos, the Pecos River, runoff from the Sacramento Mountains area, Devils River, the Rio Salado, and the Rio San Juan. This study addresses how the composition of sand forming the Rio Grande river delta into the Gulf of Mexico at Boca Chica Beach is changed …

Characterizing Polychlorinated Biphenyl Degradation Potential In Surface Water Bacteria From Rio Grande Valley, Texas Reservoirs, Alisha M. Janiga

Theses and Dissertations

The Donna Reservoir in Donna, Texas is contaminated with polychlorinated biphenyl (PCB) pollution. This reviews the current understanding of PCBs and investigate the potential of PCB degradation by native bacteria communities in the Donna Reservoir. The metabolic diversity, biphenyl tolerance, bphA1 presence were tested on surface water samples from the Donna Reservoir. The Ecoplate data suggest that the communities have a diverse metabolic capacity and the degree of plant life may interact with carbon type metabolism but not the rate of growth. Biphenyl growth curves showed that all the samples from the Donna Reservoir are tolerant to the average PCB …

Development Of Lower Rio Grande River Water Quality Transportation Numerical Model For Bi-National River Management, Jose O. Gonzalez

Theses and Dissertations

Traditionally, water quality modelling has focused on modelling individual water bodies. However, water quality management problems must be analyzed at the larger scale to include influences from various water bodies that are interconnected. This paper provides a study on the hydrologic and quality transportation calculation by developing a hydrodynamic (unsteady state) channel routing model using a water-balanced approach. A one dimension Lagrangian river model was developed and applied to the 210 plus miles for the lower Rio Grande River Basin from the Falcon Dam to the head water of Brownsville that pours onto the Gulf of Mexico. This model can …

Removal Of Lead And Arsenic From Aqueous Solution By Biochar Produced From Locally-Sourced Biomass, Sergio I. Mireles

Theses and Dissertations

This study evaluated the effectiveness of four adsorbent materials, pyrolyzed corn stover, orange peel, pistachio shell, and magnetic biochar for their ability to adsorb lead (Pb) and arsenic (As III, As V) from aqueous solution. An increase in adsorption was seen as the pH of the solution increased from pH 2 to pH 6. Magnetic orange peel biochar with Fe3O4 particles precipitated on the surface of biochar was synthetized by co-precipitation and used for arsenic adsorption. Initial pH value had an influence on the adsorption behavior of As (III) and As (V). In the pH range of 2–6, As (V) …

Investigating The Application Of Multibeam Sonar And Remotely Operated Vehicles In Fish Population Monitoring On Artificial Reefs, Robert Figueroa-Downing

Theses and Dissertations

Implementation of ROVs and multibeam imaging sonar in fisheries research has the potential to improve the accuracy and efficiency of current monitoring practices. This study aimed to 1) compare ROV video and diver abundance estimates; 2) evaluate fish length measurement accuracy from sonar; 3) investigate key differentiating sonar characteristics. Results indicate: 1) Diver surveys captured greater diversity of species; survey methods were comparable with regards to conspicuous species (r = 0.089, p = 0.074); 2) Length measurements from multibeam imaging sonar had high predictive power (Rho = 0.998; p < 0.001) of actual standard lengths and; 3) variations between samples were largely due to swim bladder echo, relative position of the target fish, and schooling characteristics. We conclude that 1) ROVs are less apt at observing cryptic species; 2) The Blueview P900-90 sonar can accurately measure fish length; and 3) swim bladder morphology plays an important role in fish identification.

South Padre Island Beach Management: Assessment Of Dune Restoration, Shelby Rose Bessette

Theses and Dissertations

Dune restoration is a common method of increasing coastal resilience. A dune restoration program was initiated by the City of South Padre Island, TX in 2010 consisting primarily of plantings of Sea Oats, Uniola paniculata, and Bitter Panicum, Panicum amarum and has continued approximately annually thereafter. These restoration efforts were evaluated in this study by comparing dune ecological structure and function among reference sites and restoration plots ranging in age from 2 to 5 years. Plant and animal communities were examined using a combination of quadrat sampling, funnel traps, pit-falls and sweep nets. Soil organic content and soil electric …