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AQUATIC INSECT (HEXAPODA) DIVERSITY IN MILLEDGEVILLE GA
No full textInsects (Hexapoda) have a fundamental role in intrinsic food webs within aquatic environments and can further serve as environmental indicators of the health of their environment. The biodiversity of aquatic hexapods was studied in two lakes between February 2021 and November 2022 in Milledgeville, Georgia using Hester-Dendy samplers. The areas surrounding the lakes differ, with one in a residential neighborhood and the other is surrounded mostly by forest. We hypothesize that the lake with a more residential area will have a more tolerant composition of bioindicator organisms, but lower diversity compared to a lake with a more a natural area. The samplers were deployed for two weeks four times a year. Specimens were identified to family level, recording the total number of individuals collected. Measuring hexapod abundance and diversity trends seasonally can indicate the overall environmental health of Lake Laurel and Oliver Hardy and reveal trends within native populations. Changes in populations might suggest declines in local environmental quality due to human activities. A comparison of diversity and abundance of known bioindicator hexapods, such as caddisflies and midges, between Lake Oliver Hardy and Lake Laurel might indicate the impact of pollutants and agricultural runoff on each lake. Lake Laurel contains more hexapod orders than Lake Oliver Hardy, and Lake Oliver Hardy experiences higher average annual water temperatures than Lake Laurel. These characteristics may reflect seasonal changes or overall environmental quality of the lakes
DETERMINING THE SOURCES OF FECAL POLLUTION IN THE WATERSHEDS OF PENSACOLA, FLORIDA
No full textPensacola, Florida (USA), has a thriving coastal community that serves many purposes, such as recreation, commerce, shellfish harvesting, and fisheries. However, increasing levels of fecal pollution pose a potential economic constraint and public health danger. Understanding the source and abundance of contaminants in streams represents an important first step for identifying the sources of fecal pollution and methods to mitigate their delivery from the landscape. This study aimed to determine the source of pollution in five highly polluted sites (Bayou Texar Lower, Willard Norris Road Creek, Clear Creek Boat Ramp @ 87, Quinette River Boat Ramp and Pensacola Bay Bridge) in the Pensacola area. DNA was extracted from water samples and then analyzed using PCR-based molecular Microbial Source Tracking techniques to determine the presence of human (HF-183-1), dog (BacCan) and avian (CP1) fecal pollution. In these urban and peri-urban creeks. Human specific fecal bacteria were detected in Bayou Texar Lower, Willard Norris Road Creek and Pensacola Bay Bridge sites. Dog specific fecal bacteria was detected in Willard Norris Road Creek, Clear Creek Boat Ramp and Pensacola Bay Bridge. There was no detection of avian specific fecal bacteria in any of the sites. The detection of human and dog fecal pollution in these coastal areas were attributed to urban developmental activities
REGIONAL AQUATIC MACROINVERTEBRATE BIODIVERSITY
No full textInvertebrates reproduce and adapt quickly which contributes to the success of this diverse group of organisms. The incredible diversity of aquatic macroinvertebrates poses a challenge when trying to identify specimens that might be used as environmental indicators. Aquatic invertebrates express different ranges of sensitivity to pollutants in their environment; therefore, the presence of certain invertebrates can be used to determine the health of a water system. The presence of less tolerant species in surface waters indicates good water quality. The state of Georgia has fourteen river basins, many of which provide drinking water and are used to fuel agricultural practices. The reliance on Georgia’s water systems make the health of these aquatic systems paramount for the state. Despite experiencing renowned aquatic biodiversity, many of the invertebrates found in Georgia are only identified to order or family level. With the long-term goal of creating a database of properly identified aquatic macroinvertebrates, a preliminary study was completed. Aquatic invertebrates were sampled from the Ocmulgee River, Lake Oconee, Lake Sinclair, the Oconee River, the Ohoopee River, the Ogeechee River, and Sapelo island using a D-net, yabbi-pump, and plankton net. Thirty-one species were identified using taxonomic keys available in the literature. Whole DNA was extracted from three individuals of each species and two genes were sequenced (18S rDNA and COI mitochondrial DNA) to aid in identification of the organisms. These data form the beginning of a database that can be used to supplement or assist future studies involving aquatic macroinvertebrates
INVESTIGATING THE RELATIONSHIP BETWEEN CHINESE PRIVET, SOIL ORGANIC CARBON, AND PHYSICAL SITE CHARACTERISTICS
No full textChinese privet (Ligustrum sinense) is an invasive shrub that is currently widespread in the Southeastern United States. Studies have shown that Chinese privet litter decomposes faster than native plant litter. This has the potential to influence the cycling of nutrients such as nitrogen and carbon especially as its abundance continues to increase. The goal of this study was to determine whether the presence of Chinese privet could influence the concentration of soil organic carbon and its relation to site characteristics. The study was done in fall 2022 at Andalusia farm in Milledgeville GA where the basal diameters of shrubs were measured in the field while site characteristics were obtained using GIS data. Ten soils samples were collected at 0–5 cm, 5–10 cm, and 10–20 cm depths from sites with heavy Chinese privet invasion and ten more at similar depths from forest sites with no Chinese privet. The samples were analyzed for organic carbon using the loss-on-ignition method. We used regression analysis to compare shrub size with site characteristics and one-way ANOVA to compare mean percent soil organic carbon. Preliminary findings show a positive correlation between shrub size and elevation as well as distance from streams. Results also show significantly higher percent soil organic carbon in soils from uninvaded sites at all depths than in soils under heavy Chinese privet invasion. This implies that less carbon is sequestered in the soils when under prolonged invasion by this shrub
COMPARISON OF AVIAN AND NON-AVIAN REPTILE DIGESTION ON SMALL MAMMAL REMAINS AND ITS IMPLICATIONS ON PALAEOECOLOGICAL INTERPRETATIONS**
No full textSmall mammals are a uniquely important group in understanding paleoecology due to their restricted habitat and sensitivity to changing environments. The use of small mammal fossils has been widely documented in taphonomical and paleontological research, mainly in the form of owl pellet analysis. However, few studies have focused on other animal clades, though a small number have examined digestive damage due to mammals and reptiles. Research presented here examines digestive modification of small mammals caused by various species of snakes, a previously unresearched taxa, compared to previous work done on owl pellets. This study lays out a systematic approach for sample collection from snake remains as well as detection and characterization of digestion modification using stereo microscopy. Comparisons of snake remains to owl remains shed light on community dynamics in ancient small mammal assemblages. Preliminary analysis of owl pellets and snake fecal remains suggest a significant difference in the destructive capacity between the two digestive systems with snakes causing extreme modification and owls causing light modification
SOIL AND HEAVY METAL CHARACTERIZATION AT TAILING DUMPS IN ZAMBIA**
No full textCopper mining is a vital economic activity for Zambia and is the main source of national income. Mining produces approximately three-quarters of the country’s export earnings. Unfortunately, mining has also resulted in millions of tons of dumped solid waste and widespread environmental degradation, as well as negative health impacts for residents living near mining areas. The goal of this project was to assess and characterize soils and heavy metal contamination at three different mine tailing waste dumps (TD) on the Copperbelt province of Zambia. Soil and plant samples were collected from three mine TD sites (TD02, TD10, and Uchi). The samples were dried in a Binder oven at 70oC for 48 hours. The samples were processed, characterized, and analyzed for heavy metals (lead, copper, zinc, cobalt, iron, arsenic, cadmium, and manganese) using an atomic absorption spectrometer (AAS). Results from these analyses were also compared to results from other studies on the Copperbelt and will be used to inform phytoremediation strategies to be employed at these sites. Preliminary results showed concentration ranges of 42 ppm to 164 ppm for copper, 0.02 ppm to 7.2 ppm for iron, 0.1 ppm to 9.2 ppm for manganese, and 0.06 ppm to 84.2 ppm for zinc. There was a difference between heavy metal concentrations found in the current study compared to other studies. This showed the variability in contamination levels and the need for different remediation approaches, even for sites that are closer to each other. Unfortunately, mining has also resulted in millions of tons of dumped solid waste and widespread environmental degradation, as well as negative health impacts for residents living near mining areas. The goal of this project was to assess and characterize soils and heavy metal contamination at three different mine tailing waste dumps (TD) on the Copperbelt province of Zambia. Soil and plant samples were collected from three mine TD sites (TD02, TD10, and Uchi). The samples were dried in a Binder oven at 70 oC for 48 hours. The samples were processed, characterized, and analyzed for heavy metals (lead, copper, zinc, cobalt, iron, arsenic, cadmium, and manganese) using an atomic absorption spectrometer (AAS). Results from these analyses were also compared to results from other studies on the Copperbelt and will be used to inform phytoremediation strategies to employed at these sites. Preliminary results showed concentration ranges of 42 ppm to 164.88 ppm for copper, 0.02 ppm to 7.18 ppm for iron, 0.12 ppm to 9.24 ppm for manganese, and 0.06 ppm to 84.2 ppm for zinc. There was a difference between heavy metal concentrations found in the current study compared to other studies. This showed the variability in contamination levels and the need for different remediation approaches, even for sites that are closer to each other
MOBILIZATION, LEACHING, AND TRANSPORT OF Pb AND Cu IN POLLUTED SOILS **
No full textMining practices have greatly increased the global presence of heavy metals in the environment, leading to damage of important ecosystem services. In some areas, heavy metals are concentrated in the top layer of the soil rendering them unusable and, in some cases, even making the areas uninhabitable by humans. The current project assesses how different soil amendments affect plant-availability and mobilization of lead (Pb) and copper (Cu) in soils. This project also investigates the effect of soil remediation on the leaching of heavy metals from polluted soils into the groundwater system. Groundwater is one of the main sources of freshwater on the planet and, therefore, needs protection from negative human impacts and contamination. To investigate the influence of soil amendments on leaching of heavy metals from contaminated soils, a greenhouse pot study in which heavy metal-contaminated soils, biochar and compost are being used in conjunction with hyperaccumulator plants is being conducted. This study will help increase our understanding of the mobilization and downward transport of leached Cu and Pb in contaminated soils. Heavy metal concentrations of the soils are analyzed at the beginning and end of the study using X-ray Fluorescence Spectrometry (XRF), while leachate is analyzed using spectrophotometry (Hach spectrophotometer) and chromatography (Dionex™ Aquion™ Ion Chromatography System). The initial soil concentrations for Pb ranged from 2000 ppm to 6000 ppm while for Cu the range was from 50 ppm to 280 ppm
CONTRASTING THE PLANCK AND RAYLEIGH JEANS RADIATION MODELS, A HISTORIC PERSPECTIVE
No full textA commonly held misconception is that Planck introduced his model for blackbody radiation, based on discrete energy, in response to the failures of classical mechanics as evidenced by the ultraviolet catastrophe observed with respect to the Rayleigh-Jeans model, based on energy equipartition. This is grossly inaccurate historically since Planck’s model precedes the Rayleigh jeans model by five years; and was obtained via application of classical electrodynamics and thermodynamics; discrete energy was subsequently introduced in the process of attaining a theoretical foundation. In this talk the historic origins of the Planck and Rayleigh-Jeans models, and their respective connections to discrete Energy, and energy equipartition will be presented. The issues that Jeans, Rayleigh, and even Planck had with discrete energy will be examined as a means of understanding the pursuit of Rayleigh-Jeans classical model, when the “correct” model had already been found by Planck. Finally, reasons for the common misconception regarding the respective origins of the Planck and Rayleigh-Jeans models will be considere
MATHEMATICAL MODELING OF POST-EXPOSURE PROPHYLAXIS OF SARS-COV-2
No full textThe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in December 2019 poses devastating effects in public health. Despite widespread availability of COVID-19 vaccines, a number of individuals who have been exposed or who are at high risk of exposure to an individual infected with SARS-CoV-2 are either not fully vaccinated or are fully vaccinated but have immune systems that cannot produce enough antibodies to fight against the virus. In such individuals, post-exposure prophylaxis (PEP) is an important approach in reducing the spread of the virus. In this project, we formulate a mathematical model for PEP against SARS-CoV-2 with multiple exposed and infectious classes, consisting of individuals on prophylaxis and those who are not on prophylaxis. The disease-free equilibrium of our model is derived, and the control reproduction number is computed, using the next generation matrix approach. We established the local stability of the disease-free equilibrium when the reproduction number is below one. The elasticity indices of the reproduction number with respect to each parameter are computed and parameters that are most sensitive in increasing/decreasing the reproduction number are identified. Results of numerical simulations indicate a decrease in the number of breakthrough cases, and contour plots indicate the possibility of eradicating the virus from the population. These results highlight the importance of post-exposure prophylaxis in individuals from the same institutional setting, such as nursing homes, prisons, or healthcare facilities
A SOCIAL ZOOARCHAEOLOGICAL INVESTIGATION OF SHARK AND RAY REMAINS FROM THE NORTHEASTERN COASTAL FLORIDA SITE OF MARINELAND **
No full textMarineland is a coastal Florida site, located in the east and central archaeological district, and occupied from the Middle Archaic (5000-3000 BC) to the St. Johns I and II periods (AD 500-1565). My focus will be on faunal remains dated between the St. Johns I and II periods. For this project, I will be conducting a zooarchaeological analysis of shark and ray remains. Zooarchaeology is the study of animal or faunal remains found in archaeological contexts. The faunal remains present at Marineland encompass a number of species, from terrestrial mammals to crabs. Historically there has been little archaeological significance given to the study of fish remains, but specifically the subgroup of Chondrichthyes better known as sharks and rays. This lack of previous research leaves a gap in the study of archaeology that should be filled to better understand how these particular species contributed to the overall diet and subsistence practices during the St. Johns I and II periods. Through looking at this topic I will be asking the following questions: What percentage of faunal remains are shark and ray? What species are represented and what are their habitats? Why were these sharks and ray species targeted? What fishing methods were used to harvest them? The goal in answering these questions is to refine our understanding of the nature and extent of shark and ray fishing at the Marineland site