Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Earth Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 3061 - 3090 of 3654

Full-Text Articles in Entire DC Network

Investigation Of Stress Changes At Mount St. Helens, Washington, And Receiver Functions At The Katmai Volcanic Group, Alaska, With An Additional Section On The Assessment Of Spreadsheet-Based Modules., Heather L. Lehto Jun 2012

Investigation Of Stress Changes At Mount St. Helens, Washington, And Receiver Functions At The Katmai Volcanic Group, Alaska, With An Additional Section On The Assessment Of Spreadsheet-Based Modules., Heather L. Lehto

USF Tampa Graduate Theses and Dissertations

Forecasting eruptions using volcano seismology is a subject that affects the lives and property of millions of people around the world. However, there is still much to learn about the inner workings of volcanoes and how this relates to the chance of eruption. This dissertation attempts to increase the breadth of knowledge aimed at helping to understand when a volcano is likely to erupt and how large that eruption might be. Chapters 2 and 3 focus on a technique that uses changes in the local stress field beneath a volcano to determine the source of these changes and help forecast …


The Effects Of Biochar Age And Concentration On Soil Retention Of Phosphorus And Infiltration Rate, Emilie Schneider Jun 2012

The Effects Of Biochar Age And Concentration On Soil Retention Of Phosphorus And Infiltration Rate, Emilie Schneider

Natural Resources Management and Environmental Sciences

Changes in land use and land management practices are regarded as one of the main factors in altering the hydrogeological system, causing changes in runoff, surface supply yields, and the quality of receiving water (Tong and Chen, 2002). Phosphorus is a significant contributor to accelerated eutrophication of fresh water and is largely sourced from agricultural runoff (Sharpley et al., 1994). The dominant processes controlling solution composition in agricultural soils are primarily ‘chemical’ for P (i.e. adsorption/desorption and dissolution/precipitation) (Edwards and Withers, 1998). Biochar has chemical characteristics that have the potential to adsorb P or influence precipitation of P insoluble pools …


Determination Of Toxic Heavy Metals In Wet Deposition And Ambient Air In Columbus, Ga, Melissa K.M. Nestor Jun 2012

Determination Of Toxic Heavy Metals In Wet Deposition And Ambient Air In Columbus, Ga, Melissa K.M. Nestor

Theses and Dissertations

Atmospheric pollution is one of the most significant and potentially catastrophic environmental issues threatening the United States and the world today. One such source of this pollution is heavy metals. The impact of heavy metal pollution on living organisms can be disastrous, having the potential to cause the deterioration of ecosystems and posing danger to the health and survival of the human race. Chronic and acute human exposure to this type of pollution can damage the proper functioning of vital body organs by inhibiting important neurological pathways. In plants, it essentially acts as a counter-agent to proper growth. In areas …


Using Landsat Thematic Mapper Satellite Imagery Assessing And Mapping Trophic State In Cheney Reservoir, Kansas, Dingnan Lu May 2012

Using Landsat Thematic Mapper Satellite Imagery Assessing And Mapping Trophic State In Cheney Reservoir, Kansas, Dingnan Lu

Master's Theses or Doctor of Nursing Practice

Eutrophication is a major inland water problem that is researched by many environmentalists and hydrologists. A eutrophic inland water body can cause many negative water problems, such as taste and odor, biotoxin, and low dissolved oxygen. Many previous studies were effective based on using remote sensing to evaluate water body trophic state. In this study, the Cheney Reservoir is selected as an object to test the performance of using remote sensing, specifically the Landsat Thematic Mapper sensor, to evaluate the trophic state of a reservoir. Based on Landsat TM imagery, the chlorophyll a concentration is estimated to be used to …


Evaluation Of Electrophoretic Protein Extraction And Database-Driven Protein Identification From Marine Sediments, Eli K. Moore, Brook L. Nunn, Jessica F. Faux, David R. Goodlett, H. Rodger Harvey May 2012

Evaluation Of Electrophoretic Protein Extraction And Database-Driven Protein Identification From Marine Sediments, Eli K. Moore, Brook L. Nunn, Jessica F. Faux, David R. Goodlett, H. Rodger Harvey

OES Faculty Publications

Intact proteins comprise a major component of organic carbon and nitrogen produced globally and are likely an important fraction of organic matter in sediments and soils. Extracting the protein component from sediments and soils for mass spectral characterization and identification represents a substantial challenge given the range of products and functionalities present in the complex matrix. Multiple forms of gel electrophoresis were evaluated as a means of enhancing recovery of sedimentary protein before proteomic characterization and compared with a direct enzymatic digestion of proteins in sediments. Resulting tryptic peptides were analyzed using shotgun proteomics and tandem mass spectra were evaluated …


Strawberry Growth, Yield, Fruit Nutrition, And Control Of Verticillium Wilt With Pre-Plant Soil Fumigants, Ozone, And Biological Control, Justin J. Scurich Apr 2012

Strawberry Growth, Yield, Fruit Nutrition, And Control Of Verticillium Wilt With Pre-Plant Soil Fumigants, Ozone, And Biological Control, Justin J. Scurich

Master's Theses

Verticillium wilt is a widespread soilborne disease of strawberry historically controlled by soil fumigation with methyl bromide (MB). MB was banned by the United Nations in 1995 and will be completely phased out by 2015. Research has concentrated on alternative methods of disease control without finding a single alternative able to replace MB in widespread disease control and yield increase. For the current study, strawberries were greenhouse grown in container pots filled with soil from both infested and non-infested areas of a commercial strawberry field in Watsonville, CA. Treatments included pre-plant soil fumigation with commercially available formulations of methyl bromide, …


The Transcriptome And Proteome Of The Diatom Thalassiosira Pseudonana Reveal A Diverse Phosphorus Stress Response, Sonya T. Dyhrman, Bethany D. Jenkins, Tatiana A. Rynearson, Mak A. Saito, Melissa L. Mercier, Harriet Alexander, Leann P. Whitney, Andrea Drzewianowski, Vladimir V. Bulygin, Erin M. Bertrand, Zhijin Wu, Claudia R. Benitez-Nelson, Abigail Heithoff Mar 2012

The Transcriptome And Proteome Of The Diatom Thalassiosira Pseudonana Reveal A Diverse Phosphorus Stress Response, Sonya T. Dyhrman, Bethany D. Jenkins, Tatiana A. Rynearson, Mak A. Saito, Melissa L. Mercier, Harriet Alexander, Leann P. Whitney, Andrea Drzewianowski, Vladimir V. Bulygin, Erin M. Bertrand, Zhijin Wu, Claudia R. Benitez-Nelson, Abigail Heithoff

Faculty Publications

Phosphorus (P) is a critical driver of phytoplankton growth and ecosystem function in the ocean. Diatoms are an abundant class of marine phytoplankton that are responsible for significant amounts of primary production. With the control they exert on the oceanic carbon cycle, there have been a number of studies focused on how diatoms respond to limiting macro and micronutrients such as iron and nitrogen. However, diatom physiological responses to P deficiency are poorly understood. Here, we couple deep sequencing of transcript tags and quantitative proteomics to analyze the diatom Thalassiosira pseudonana grown under P-replete and P-deficient conditions. A total of …


A Review Of The Eocene Diodontids And Labrids From Transylvania, Emanuel Paul Dica Mar 2012

A Review Of The Eocene Diodontids And Labrids From Transylvania, Emanuel Paul Dica

Studia UBB Geologia

This paper reviews two diodontids and labrids species: Chylomicterus hilgendorfi and Lachnolaimus multidens. The paleontological material is represented only from jaws and pharyngeal bones, which had been recently collected from Cluj Limestone (Cluj Napoca and Turbut̡a areas), and Nis̡ului Valley Formation (Turnu Ros̡u) as well as from older collections. The holotypes of these species are reconsidered and the paleoecological significances are also discussed.


Farmer Panel--Managed Grazing And Profits, Bill Payne Feb 2012

Farmer Panel--Managed Grazing And Profits, Bill Payne

Kentucky Alfalfa and Stored Forage Conference

Profits are the goal of any business model and mine is no exception. My plan assumes that available natural resources are efficiently utilized in a responsible manner.I have chosen to implement that plan by producing, managing and marketing our forage resources by utilizing Management Intensive Grazing (MIG.)


Role And Importance Of Alfalfa In Beef Diets, Jeff Lehmkuhler Feb 2012

Role And Importance Of Alfalfa In Beef Diets, Jeff Lehmkuhler

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is often referred to as the “Queen” of forage. Is this because of its high fertility needs and more finicky soil fertility needs along with greater management for optimal growth and persistency? Or is it because of it being on top of nearly all other forages for yield and quality? Truth be told, it is likely a combination of all these factors. Alfalfa is a versatile forage as it can be harvested for hay or silage and also grazed with proper management. For these reasons, this forage can fit well in beef operations.


Alfalfa Hay For Horses, Robert Coleman Feb 2012

Alfalfa Hay For Horses, Robert Coleman

Kentucky Alfalfa and Stored Forage Conference

When horse owners consider hay for their horses, a number of criteria are generally considered. Of major importance is the hay must be free of mold and dust. It needs to contain nutrients needed by the horse and it must be palatable. If these criteria are met, the type of hay should not matter. However, that is not the case with many horse owners. When discussing the selection of hay, many owners first consider the type of hay. Can it be alfalfa or should it be a grass or how about a mix of grass and a legume. If a …


Kentucky Department Of Agriculture Hay Testing Program, Kim Field Feb 2012

Kentucky Department Of Agriculture Hay Testing Program, Kim Field

Kentucky Alfalfa and Stored Forage Conference

The Kentucky Department of Agriculture offers a forage testing service which provides nutritional and energy value information. A Kentucky Department of Agriculture staff member will take sample(s) of hay and/or haylage at the farm and analyze them in the Kentucky Department of Agriculture Forage Laboratory located in Frankfort. Tested forages can mean higher profit, whether feeding cattle, horses, goats, sheep or other livestock. By knowing the nutritional and energy value, you can minimize your cost and maximize your production.


Wayne E. Sabbe Arkansas Soil Fertility Studies 2011, Nathan A. Slaton Feb 2012

Wayne E. Sabbe Arkansas Soil Fertility Studies 2011, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil-test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.


A Global Assessment Of The Water Footprint Of Farm Animal Products, Mesfin Mekonnen, Arjen Y. Hoekstra Jan 2012

A Global Assessment Of The Water Footprint Of Farm Animal Products, Mesfin Mekonnen, Arjen Y. Hoekstra

Daugherty Water for Food Global Institute: Faculty Publications

The increase in the consumption of animal products is likely to put further pressure on the world’s freshwater resources. This paper provides a comprehensive account of the water footprint of animal products, considering different production systems and feed composition per animal type and country. Nearly one-third of the total water footprint of agriculture in the world is related to the production of animal products. The water footprint of any animal product is larger than the water footprint of crop products with equivalent nutritional value. The average water footprint per calorie for beef is 20 times larger than for cereals and …


Groundwater Quality And Its Health Impact: An Assessment Of Dental Fluorosis In Rural Inhabitants Of The Main Ethiopian Rift, Tewodros Rango, Julia Kravchenko, Behailu Atlaw, Peter G. Mccornick, Marc Jeuland, Brittany Merola, Avner Vengosh Jan 2012

Groundwater Quality And Its Health Impact: An Assessment Of Dental Fluorosis In Rural Inhabitants Of The Main Ethiopian Rift, Tewodros Rango, Julia Kravchenko, Behailu Atlaw, Peter G. Mccornick, Marc Jeuland, Brittany Merola, Avner Vengosh

Daugherty Water for Food Global Institute: Faculty Publications

This study aims to assess the link between fluoride content in groundwater and its impact on dental health in rural communities of the Ethiopian Rift. A total of 148 water samples were collected from two drainage basins within the Main Ethiopian Rift (MER). In the Ziway-Shala basin in particular, wells had high fluoride levels (mean: 9.4 ± 10.5 mg/L; range: 1.1 to 68 mg/L), with 48 of 50 exceeding the WHO drinking water guideline limit of 1.5 mg/L. Total average daily intake of fluoride from drinking groundwater (calculated per weight unit) was also found to be six times higher than …


Livestock Foraging Behavior In Response To Sequence And Interactions Among Alkaloids, Tannins, And Saponins, Tiffany L. Jensen Jan 2012

Livestock Foraging Behavior In Response To Sequence And Interactions Among Alkaloids, Tannins, And Saponins, Tiffany L. Jensen

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Critique On The Use Of The Standardized Avian Acute Oral Toxicity Test For First Generation Anticoagulant Rodenticides, Nimish B. Vyas, Barnett A. Rattner Jan 2012

Critique On The Use Of The Standardized Avian Acute Oral Toxicity Test For First Generation Anticoagulant Rodenticides, Nimish B. Vyas, Barnett A. Rattner

United States Geological Survey: Staff Publications

Avian risk assessments for rodenticides are often driven by the results of standardized acute oral toxicity tests without regards to a toxicant’s mode of action and time course of adverse effects. First generation anticoagulant rodenticides (FGARs) generally require multiple feedings over several days to achieve a threshold concentration in tissue and cause adverse effects. This exposure regimen is much different than that used in the standardized acute oral toxicity test methodology. Median lethal dose values derived from standardized acute oral toxicity tests underestimate the environmental hazard and risk of FGARs. Caution is warranted when FGAR toxicity, physiological effects, and pharmacokinetics …


Climate Change And Infectious Disease Dynamics, Raina K. Plowright, Paul C. Cross, Gary M. Tabor, Emily Almberg, Leslie Bienen, Peter J. Hudson Jan 2012

Climate Change And Infectious Disease Dynamics, Raina K. Plowright, Paul C. Cross, Gary M. Tabor, Emily Almberg, Leslie Bienen, Peter J. Hudson

United States Geological Survey: Staff Publications

The International Panel on Climate Change has made an unequivocal case that the earth's climate is changing in profound ways, and that human activities are contributing significantly to climate disruption (IPCC 2007). The weight of evidence demonstrates warming global temperatures, changing patterns of precipitation, and increasing climate variability, with more extreme events. Thus, the physical underpinnings of ecology are changing, with pervasive effects on disease dynamics. Interactions among environment, hosts, and pathogens drive disease processes, and climate change will influence every interaction in this triad, directly and indirectly.


Sorta Situ: The New Reality Of Management Conditions For Wildlife Populations In The Absence Of "Wild" Spaces, Barbara A. Wolfe, Roberto F. Aguilar, A. Alonso Aguirre, Glenn H. Olsen, Evan S. Blumer Jan 2012

Sorta Situ: The New Reality Of Management Conditions For Wildlife Populations In The Absence Of "Wild" Spaces, Barbara A. Wolfe, Roberto F. Aguilar, A. Alonso Aguirre, Glenn H. Olsen, Evan S. Blumer

United States Geological Survey: Staff Publications

The rate of species loss today is approaching catastrophic levels. Scientists project that over the next two decades, more than 1 million species of plants and animals will become extinct. E.O. Wilson has estimated that "the rate ofloss may exceed 50,000 a year, 137 a day ... this rate, while horrendous, is actually the minimal estimate, based on the species/area relationship alone" (Kellert and Wilson 1993, p. 16; Aguirre 2009). Ever-expanding communities, strained natural resources, changes in land use, and other anthropogenic drivers are compromising ecosystems and rapidly changing the landscape and the availability of "wild" spaces.


Co-Grazing Beef Cattle And Goats In Kentucky, David C. Ditsch, Patty Scharko Jan 2012

Co-Grazing Beef Cattle And Goats In Kentucky, David C. Ditsch, Patty Scharko

Plant and Soil Sciences Research Report

A two season grazing study of mixed (goats and beef cattle) species was conducted in 2006 and 2008 at Sebastian Farms in Breathitt County KY. The objective of this study was to determine if the order of mixed species grazing affected beef cattle and goat weight gain and goat exposure to the barber pole worm (Haemonchus contortus) in a rotational grazing system. In this study, two co-grazing management strategies were tested. In treatment 1, goats and cattle were rotationally grazed together. In treatment 2, goats rotated through pastures as first grazers followed by cattle. Each co-grazing treatment was …


Droughtscape, Winter 2012, National Drought Mitigation Center Jan 2012

Droughtscape, Winter 2012, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Drought Planning for Kansas Ranchers Jan. 21

South Hoping La Niña Dryness Stays Away

2011 Brought Record-Breaking Extent of D4

Reported Impacts Ease as Growing Season Ends

Disaster Planning in Nanjing at Hohai U

Ag, Fire and Water Supply Topped 2011 Impacts


Copper Pellets Simulating Oral Exposure To Copper Ammunition: Absence Of Toxicity In American Kestrels (Falco Sparverius), J. Christian Franson, Lesanna L. Lahner, Carol U. Meteyer, Barnett A. Rattner Jan 2012

Copper Pellets Simulating Oral Exposure To Copper Ammunition: Absence Of Toxicity In American Kestrels (Falco Sparverius), J. Christian Franson, Lesanna L. Lahner, Carol U. Meteyer, Barnett A. Rattner

United States Geological Survey: Staff Publications

To evaluate the potential toxicity of copper

(Cu) in raptors that may consume Cu bullets, shotgun

pellets containing Cu, or Cu fragments as they feed on

wildlife carcasses, we studied the effects of metallic Cu

exposure in a surrogate, the American kestrel (Falco

sparverius). Sixteen kestrels were orally administered

5 mg Cu/g body mass in the form of Cu pellets

(1.18–2.00 mm in diameter) nine times during 38 days and

10 controls were sham gavaged on the same schedule. With

one exception, all birds retained the pellets for at least 1 h,

but most (69%) regurgitated pellets during …


The Population Structure Of Escherichia Coli Isolated From Subtropical And Temperate Soils, Muruleedhara N. Byappanahalli, Tao Yan, Matthew J. Hamilton, Satoshi Ishii, Roger S. Fujioka, Richard L. Whitman, Michael J. Sadowsky Jan 2012

The Population Structure Of Escherichia Coli Isolated From Subtropical And Temperate Soils, Muruleedhara N. Byappanahalli, Tao Yan, Matthew J. Hamilton, Satoshi Ishii, Roger S. Fujioka, Richard L. Whitman, Michael J. Sadowsky

United States Geological Survey: Staff Publications

While genotypically-distinct naturalized Escherichia coli strains have been shown to occur in riparian soils of Lake Michigan and Lake Superior watersheds, comparative analyses of E. coli populations in diverse soils across a range of geographic and climatic conditions have not been investigated. The main objectives of this study were to: (a) examine the population structure and genetic relatedness of E. coli isolates collected from different soil types on a tropical island (Hawaii), and (b) determine if E. coli populations from Hawaii and temperate soils (Indiana, Minnesota) shared similar genotypes that may be reflective of biome-related soil conditions. DNA fingerprint and …


Effects Of Root-Zone Temperature And N, P, And K Supplies On Nutrient Uptake Of Cucumber (Cucumis Sativus L.) Seedlings In Hydroponics, Qiuyan Yan, Zengqiang Duan, Jingdong Mao, Xun Li, Fei Dong Jan 2012

Effects Of Root-Zone Temperature And N, P, And K Supplies On Nutrient Uptake Of Cucumber (Cucumis Sativus L.) Seedlings In Hydroponics, Qiuyan Yan, Zengqiang Duan, Jingdong Mao, Xun Li, Fei Dong

Chemistry & Biochemistry Faculty Publications

The nutrient uptake and allocation of cucumber (Cucumis sativus L.) seedlings at different root-zone temperatures (RZT) and different concentrations of nitrogen (N), phosphorus (P), and potassium (K) nutrients were examined. Plants were grown in a nutrient solution for 30 d at two root-zone temperatures (a diurnally fluctuating ambient 10°C-RZT and a constant 20° C-RZT) with the aerial parts of the plants maintained at ambient temperature (10°C -30°C). Based on a Hoagland nutrient solution, seven N, P, and K nutrient concentrations were supplied to the plants at each RZT. Results showed that total plant and shoot dry weights under …


Evaluation Of Pleistocene To Holocene (Mis 5 To 1) Climatic Changes In Southwestern Black Sea: A Palynological Study Of Dsdp Site 380, Shannon Ferguson Jan 2012

Evaluation Of Pleistocene To Holocene (Mis 5 To 1) Climatic Changes In Southwestern Black Sea: A Palynological Study Of Dsdp Site 380, Shannon Ferguson

LSU Master's Theses

Site 380 of the Deep Sea Drilling Program [DSDP] is located in the southwestern region of the Black Sea (42°05.94’, 29°36.82’E). The location of this site is important due to its proximity to the narrow Bosphorus strait, the only present-day connection between the Black Sea and the Aegean Sea. Drops in eustatic sea level during extensive Pleistocene glacial episodes disconnected the Black Sea from the Aegean Sea at the Bosphorus strait, creating a change from brackish to freshwater within the Black Sea during these intervals. Organic-walled phytoplankton (dinoflagellate cysts, acritarchs, and fresh-water algae) are investigated to better constrain these glacio-eustatic …


Changing Land Use On Unproductive Soils, Andrew Blake, Mike Clarke, Angela Stuart-Street Jan 2012

Changing Land Use On Unproductive Soils, Andrew Blake, Mike Clarke, Angela Stuart-Street

Resource management technical reports

A three year study completed in 2010 examined farming systems in the north-eastern agricultural region and eastern wheatbelt of Western Australia which experienced a succession of variable seasons from 2000. This culminated in severe drought in 2006 and 2007. At that time, farmers experienced labour shortages and declining terms of trade triggered by cost inflation outpacing growth in commodity prices. As a result, farm business equity was eroded as farm debt escalated. This left many farm businesses in a highly vulnerable state. At the time of the study many farmers were facing an uncertain future.

These experiences, coupled with a …


Great Plains Soils May Be C Sinks, David E. Clay, Gregg C. Carlson, Sharon A. Clay, James Stone, Kurtis Reitsma, Ronald Gelderman Jan 2012

Great Plains Soils May Be C Sinks, David E. Clay, Gregg C. Carlson, Sharon A. Clay, James Stone, Kurtis Reitsma, Ronald Gelderman

Agronomy, Horticulture and Plant Science Faculty Publications

Numerous studies with wide-ranging results have been conducted to resolve if Great Plains soils are a C source or sink. The authors addressed the source/sink question by examining the results from producer soil samples and production surveys that were analyzed and archived by the South Dakota Soil Testing Laboratory. Results showed that between 1985 and 2010, soil organic C content increased at a rate of 326 lb C/A/year, for a total increase of 24%. The increase was attributed to planting better adapted varieties and using better management practices that on average increased corn grain yields 2.29 bu/A/year. Higher soil organic …


Identifying Risk Factors For Disparities In Breast Cancer Mortality Among African-American And Hispanic Women, Nancy Tian, Pierre Goovaerts, F. Benjamin Zhan, T. Edwin Chow, Jeff Gaines Wilson Jan 2012

Identifying Risk Factors For Disparities In Breast Cancer Mortality Among African-American And Hispanic Women, Nancy Tian, Pierre Goovaerts, F. Benjamin Zhan, T. Edwin Chow, Jeff Gaines Wilson

School of Earth, Environmental, & Marine Sciences Faculty Publications

Background: This study evaluated the risk factors associated with racial disparities in female breast cancer mortality for African-American and Hispanic women at the census tract level in Texas from 1995 to 2005.

Methods: Data on female breast cancer cases were obtained from the Texas Cancer Registry. Socioeconomic and demographic data were collected from Census 2000. Network distance and driving times to mammography facilities were estimated using Geographic Information System techniques. Demographic, poverty and spatial accessibility factors were constructed using principal component analysis. Logistic regression models were developed to predict the census tracts with significant racial disparities in breast cancer mortality …


Provenance And Geological Significance Of Red Mud And Other Clastic Sediments Of The Mugnano Cave (Montagnola Senese, Italy), Francesco Iacoviello, Ivan Martini Jan 2012

Provenance And Geological Significance Of Red Mud And Other Clastic Sediments Of The Mugnano Cave (Montagnola Senese, Italy), Francesco Iacoviello, Ivan Martini

International Journal of Speleology

The Mugnano cave is characterized by a thick clastic sedimentary fill showing a great variability of sedimentary facies, ranging from clay to coarse-grained sand deposits. This paper deals with combined sedimentological and mineralogical (XRD and SEM) studies of these sediments and bedrock insoluble residues in order to understand the origin and geological significance of cave deposits, with particular attention to red mud sediments, often considered as the residue of host rock dissolution. Three different sedimentary facies were recognized: i) YS, yellow sand with occasionally shell fragments, testifying the arrival of sediments from the surrounding landscape; ii) RS, red laminated mud; …


Stable Isotope Analysis Of Busycon Sinistrum To Determine Fort Walton-Period Seasonality At St. Joseph Bay, Northwest Florida, Ryan Michael Harke Jan 2012

Stable Isotope Analysis Of Busycon Sinistrum To Determine Fort Walton-Period Seasonality At St. Joseph Bay, Northwest Florida, Ryan Michael Harke

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Recent archaeological investigations indicate that coastal Fort Walton cultures in the St. Joseph Bay region of northwest Florida emphasized marine and estuarine foraging. These late prehistoric (A.D. 1000-1500) peoples collected fish, shellfish, and other aquatic resources. At the Richardson's Hammock site (8Gu10), radiocarbon-dated to about A.D. 1300, as at dozens of other shell middens around this salty bay, large gastropods were a major subsistence component. This adaptation is in sharp contrast with that of contemporaneous inland Fort Walton societies, who relied on maize agriculture. It is unknown whether coastal groups represent separate hunter-gatherer-fisher populations or seasonal migrations by inland …