Regulatory Mechanisms in Biosystems (E-Journal - Dnipro National University)
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Close up of the Corpus Christi High School Postcard
No full textClose up of the Corpus Christi High School Postcard built in 1912, known as the Brick Palace on Carancahua stree
Carbonate chemistry trends in the northwestern gulf of Mexico
No full textHumans over the years have contributed to the changes in sea water chemistry. These changes stem from human caused carbon dioxide (CO2) releasing activities related to burning of fossil fuels, cement production, and land use changes associated with agricultural activities among others. From the beginning of the industrial revolution atmospheric CO2 has increased from 280 ppm to the current 419 ppm. In the same period, global oceans have taken in 30% of the global emissions as dissolved CO2 therefore playing a role in climate change mitigation. Increase in dissolved CO2 causes ocean acidification (OA). In the northwestern Gulf of Mexico (nwGOM), a decadal acidification has been observed in the shelf-slope region. For coastal areas the short term and long-term changes in the carbonate chemistry vary by location and can be influenced by river input, water stratification, ocean currents, and biogeochemical processes (photosynthesis, respiration, carbonate formation and dissolution). Despite its ecological and economic significance, the Gulf of Mexico and its current OA conditions are still misunderstood. This preliminary master’s thesis research will focus on spatial and temporal changes of carbonate chemistry trends of the nwGOM with a goal to understand the regions carbon dioxide sequestration over the past 5-10 years. Open access data from the Gulf of Mexico and East Coast Carbon (GOMECC) cruises-2007, 2012, 2017 and 2021 have been employed to explore this question. These expeditions have supplied comprehensive measurements of all primary inorganic carbon system parameters in these coastal waters. In addition, automated devices such as gliders equipped with sensors also collected additional measurements
Photograph of McCleudow, Elliot, Conrad, Ed Noyes
No full textPhotograph of McCleudow, Elliot, Conrad, Ed Noye
A risk assessment of genetically divided oyster populations in South Texas
No full textThe eastern oyster, Crassostrea virginica, is a valuable foundational species providing critical ecosystem services and an economically valuable fishery and aquaculture industry for the state of Texas. However, Texas’ top commercial fishery will be threatened by population growth, coastal development, pollution, and flooding. In addition, these local threats will interact with global environmental changes, so it is vital to understand the species’ specific stress tolerances and adaptive capacities. This Texas oyster population is divided into two genetically different sub-species found in the Northern and Southern regions of the state, with Corpus Christi Bay acting as the transition zone between the divergent populations. However, few scientific conclusions have been made regarding why there is such vast genetic variation between the two populations of oysters in Texas. Therefore, this project will characterize the individual tolerance thresholds of the genetically different sub-populations to a range of salinities under high temperature using an intermittent flow respirometry technique. The results of this work aim to help predict future risk and resilience of the South Texas oyster population dynamics, aquaculture production, and restoration of ecosystem services. The risk assessment created will contribute to the resiliency of Texas’ coastal oyster reef habitats to climate change by filling the knowledge gap surrounding stress tolerances to dramatic salinity fluctuations and evaluating how the genetically different oyster populations will respond to interacting local and global stressors
Photograph of a Sketch by R. Hollub, place called Agna Poquito, near San Diego
No full textPhotograph of a Sketch by R. Hollub, place called Agna Poquito, near San Dieg
Observations and parametrization of the turbulent energy dissipation beneath non-breaking waves
No full textHere, for non-breaking short surface waves, we have experimentally determined the value of the turbulent eddy viscosity νT or its ratio ν ∗ T ≡ νT/ν, where ν is the water kinematic viscosity. The non-breaking wave-generated turbulent eddy viscosity νT was found to depend on the ratio of the wave period, T, to the microscale Kolmogorov time scale, τη. Our observations were consistent with ν ∗ T = 1.46 · (T/τη) −2.6 when (T/τη) < 0.9. That implied that the ν ∗ T ∝ e −1.3, where e is the background turbulent energy dissipation rate. The near-surface turbulent flow associated with non breaking waves was characterized by a short inertial subrange. The background turbulence appears to modulate the amount of energy the non-breaking waves dissipate locally and, consequently, the wave’s decay rate. Our results imply that the background turbulent flow acts as a lubricant, permitting waves to propagate further when traveling over a more energetic turbulent background flow. Our results have implications for the modeling of oceanic wave propagation or the air–sea exchange processes.This research was made possible in part by a grant from the Gulf of Mexico Research Initiative and in part by the National Science Foundation grant 1434670
Photograph of group of people sitting on the rocks of a bank of stream of river
No full textPhotograph of group of people sitting on the rocks of a bank of stream of rive
