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

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 571 - 600 of 773

Full-Text Articles in Other Oceanography and Atmospheric Sciences and Meteorology

Teleconnections In Steam: Antarctic Field-Camp Art, Craig Stevens, Gabby O'Connor Nov 2016

Teleconnections In Steam: Antarctic Field-Camp Art, Craig Stevens, Gabby O'Connor

The Transdisciplinary STEAM+ Journal

We describe a component of a multi-element STEAM collaboration looking to explore ideas around the life cycle of Antarctic sea ice. One of the intermediate phases of the work involved the scientist deploying partially pre-made art components. Results were modulated by weather and operational constraints and generated a sequence of images and recordings as well as greater understanding of the creative collaboration process.


Analysis Of Aerosol Absorption Properties And Transport Over North Africa And The Middle East Using Aeronet Data, Ashraf Farahat, Hesham El-Askary, Peter Adetokunbo, Abu-Tharr Fuad Nov 2016

Analysis Of Aerosol Absorption Properties And Transport Over North Africa And The Middle East Using Aeronet Data, Ashraf Farahat, Hesham El-Askary, Peter Adetokunbo, Abu-Tharr Fuad

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this paper particle categorization and absorption properties were discussed to understand transport mechanisms at different geographic locations and possible radiative impacts on climate. The long-term Aerosol Robotic Network (AERONET) data set (1999–2015) is used to estimate aerosol optical depth (AOD), single scattering albedo (SSA), and the absorption Ångström exponent (abs) at eight locations in North Africa and the Middle East. Average variation in SSA is calculated at four wavelengths (440, 675, 870, and 1020 nm), and the relationship between aerosol absorption and physical properties is used to infer dominant aerosol types at different locations. It was found that seasonality …


Development Of A Risk Assessment Framework To Predict Invasive Species Establishment For Multiple Taxonomic Groups And Vectors Of Introduction, Alisha D. Davidson, Abigail J. Fusaro, Rochelle A. Sturtevant, Edward S. Rutherford, Donna R. Kashian Nov 2016

Development Of A Risk Assessment Framework To Predict Invasive Species Establishment For Multiple Taxonomic Groups And Vectors Of Introduction, Alisha D. Davidson, Abigail J. Fusaro, Rochelle A. Sturtevant, Edward S. Rutherford, Donna R. Kashian

Biological Sciences Faculty Research Publications

A thorough assessment of aquatic nonindigenous species’ risk facilitates successful monitoring and prevention activities. However, species- and vector-specific information is often limited and difficult to synthesize across a single risk framework. To address this need, we developed an assessment framework capable of estimating the potential for introduction, establishment, and impact by aquatic nonindigenous species from diverse spatial origins and taxonomic classification, in novel environments. Our model builds on previous approaches, while taking on a new perspective for evaluation across species, vectors and stages to overcome the limitations imposed by single species and single vector assessments. We applied this globally-relevant framework …


A Habitat Analysis Of Estuarine Fishes And Invertebrates, With Observations On The Effects Of Habitat-Factor Resolution, Brianna Michaud Nov 2016

A Habitat Analysis Of Estuarine Fishes And Invertebrates, With Observations On The Effects Of Habitat-Factor Resolution, Brianna Michaud

USF Tampa Graduate Theses and Dissertations

Between 1988 and 2014, otter trawls, seine nets, and plankton nets were deployed along the salinity gradients of 18 estuaries by the University of South Florida and the Florida Fish and Wildlife Research Institute (FWRI, a research branch of the Florida Fish and Wildlife Conservation Commission). The purpose of these surveys was to document the responses of aquatic estuarine biota to variation in the quantity and quality of freshwater inflows that were being managed by the Southwest Florida Water Management District (SWFWMD).

In the present analyses, four community types collected by these gears were compared with a diversity of habitat …


Seasonal Temperature Variations Controlling Cave Ventilation Processes In Cueva Larga, Puerto Rico, Rolf Vieten, Amos Winter, Sophie Friederike Warken, Andrea Schrӧder-Ritzrau, Thomas E. Miller, Denis Scholz Oct 2016

Seasonal Temperature Variations Controlling Cave Ventilation Processes In Cueva Larga, Puerto Rico, Rolf Vieten, Amos Winter, Sophie Friederike Warken, Andrea Schrӧder-Ritzrau, Thomas E. Miller, Denis Scholz

International Journal of Speleology

Two years of cave monitoring investigate ventilation processes in Cueva Larga, a tropical cave in Puerto Rico. The cave is 1,440 m long with a large main passage (about 120,000 m3). Cave air pCO2 in the main passage varies seasonally, between 600 ppm in winter and 1,800 ppm in summer. The seasonal variability in cave pCO2 permits the estimation of a cave air exchange time of 36 ± 5 days and a winter ventilation rate of 3,300 ± 1,000 m3/day for the main cave passage. Calculations of virtual temperature and differences between cave and …


Abundance Of Archaias Angulatus On The West Florida Coast Indicates The Influence Of Carbonate Alkalinity Over Salinity, Sean Thomas Beckwith Oct 2016

Abundance Of Archaias Angulatus On The West Florida Coast Indicates The Influence Of Carbonate Alkalinity Over Salinity, Sean Thomas Beckwith

USF Tampa Graduate Theses and Dissertations

Archaias angulatus, a large symbiont-bearing foraminifer (Order Miliolida) that produces a Mg-calcite shell, is common throughout the Caribbean and warm western Atlantic region. This species lives abundantly in seagrass beds along the Springs Coast of northwest Florida (up to 4 adults per gram of sediment) where spring-fed rivers emerge from a limestone aquifer, and in Florida Bay to the southeast (25 adults/g) where the sediment is primarily biogenic carbonate. In contrast, live specimens are seldom found in the seagrass beds along the central-west coast of Florida, where barrier islands are dominated by quartz sand. My working hypothesis is that substratum …


Weights And Balances: Integrating Models For Prevention And Response To Southern California Offshore Oil Spills, Carmen Watts Clayton, Amoret Bunn Oct 2016

Weights And Balances: Integrating Models For Prevention And Response To Southern California Offshore Oil Spills, Carmen Watts Clayton, Amoret Bunn

STAR Program Research Presentations

Licensing offshore oil and gas reserves in the United States waters are overseen by the U.S. Department of the Interior’s Bureau of Safety and Enforcement (BSEE). The licensing application includes planning for any worst-case oil spill scenario between BSEE and the applicant based on lessons learned from historic offshore spills such as the Deepwater Horizon (2010), Exxon Valdez (1989), and the Union Oil Platform Blowout (1969). The process for planning to respond to oil spills involves coordination with multiple agencies, trustees, and stakeholders to ensure that oil spill responses consider multiple factors, including ecologically sensitive species, commercial transportation and fisheries, …


Determining The Viability Of Recent Storms As Modern Analogues For North-Central Gulf Of Mexico Paleotempestology Through Sedimentary Analysis And Storm Surge Reconstruction, Joshua Caleb Bregy Aug 2016

Determining The Viability Of Recent Storms As Modern Analogues For North-Central Gulf Of Mexico Paleotempestology Through Sedimentary Analysis And Storm Surge Reconstruction, Joshua Caleb Bregy

Master's Theses

The northern Gulf of Mexico has been devastated by recent intense storms. Camille (1969) and Katrina (2005) are two notable hurricanes that made landfall in virtually the same location in Mississippi. However, fully understanding the risks and processes associated with hurricane impacts is impeded by a short and fragmented instrumental record. Paleotempestology could potentially use modern analogues from intense storms in this region to extend the hurricane record back to pre-observational time. Existing empirically based models can back-calculate surge heights over coastal systems as a function of transport distance, particle settling velocity, and gravitational acceleration. We collected cores in a …


Karst Landscape Influence On The Planetary Boundary Layer Atmosphere, Zachary S. Sullivan Jul 2016

Karst Landscape Influence On The Planetary Boundary Layer Atmosphere, Zachary S. Sullivan

Masters Theses & Specialist Projects

Karst landscapes cover approximately 20% of the ice-free land area worldwide. The soluble nature of the bedrock within a karst landscape allows for the formation of caverns, joints, fissures, sinkholes, and underground streams, which affect the hydrological behavior of the region. Currently, the Noah Land-Surface Model (Noah- LSM), coupled with the Weather Research and Forecasting (WRF) model, does not provide a representation of the physical behavior of a karst terrain. Previous research has attempted to model karst behavior through soil moisture and land cover/land use changes to determine the influence this unique landscape may have on atmospheric phenomenon. This highlights …


Photic Stress In Symbiont-Bearing Reef Organisms: Analyses Of Photosynthetic Performance, Natasha Mendez-Ferrer Jul 2016

Photic Stress In Symbiont-Bearing Reef Organisms: Analyses Of Photosynthetic Performance, Natasha Mendez-Ferrer

USF Tampa Graduate Theses and Dissertations

Photo-oxidative stress is one of the key factors that can induce bleaching in reef organisms. With the decline of coral reefs and recurrent bleaching events, many studies have focused on understanding the mechanism behind this phenomenon. Two of the hypotheses that explain how the photosynthetic performance of the symbiont is affected and influences bleaching are: (1) disruption of the photosynthetic pathway by direct damage to the photosystem II (PSII), and (2) by inhibition of the Calvin-Benson cycle. In this dissertation I examine different aspects of photosynthetic performance in symbiont-bearing reef organisms and how this is influenced by symbiont loss and …


Carbon Nanotubes Affect The Toxicity Of Cuo Nanoparticles To Denitrification In Marine Sediments By Altering Cellular Internalization Of Nanoparticle, Xiong Zheng, Yinglong Su, Yinguang Chen, Rui Wan, Mu Li, Haining Huang, Xu Li Jun 2016

Carbon Nanotubes Affect The Toxicity Of Cuo Nanoparticles To Denitrification In Marine Sediments By Altering Cellular Internalization Of Nanoparticle, Xiong Zheng, Yinglong Su, Yinguang Chen, Rui Wan, Mu Li, Haining Huang, Xu Li

Department of Civil and Environmental Engineering: Faculty Publications

Denitrification is an important pathway for nitrate transformation in marine sediments, and this process has been observed to be negatively affected by engineered nanomaterials. However, previous studies only focused on the potential effect of a certain type of nanomaterial on microbial denitrification. Here we show that the toxicity of CuO nanoparticles (NPs) to denitrification in marine sediments is highly affected by the presence of carbon nanotubes (CNTs). It was found that the removal efficiency of total NOX-N (NO3-N and NO2-N) in the presence of CuO NPs was only 62.3%, but it …


Northern San Francisco Bay Ecological Risk Assessment: Potential Crude By Rail Incident, Meagan Bowis May 2016

Northern San Francisco Bay Ecological Risk Assessment: Potential Crude By Rail Incident, Meagan Bowis

Master's Projects and Capstones

Oil spill models, ecological risks, response options, and costs were assessed for a discharge of Bakken crude oil into the Northern San Francisco Bay from a train derailment. This assessment was based on the risk of crude by rail derailments into the San Francisco Bay; in 2014, California oil refineries imported over 240 million gallons of Bakken crude oil by rail for processing. A hypothetical scenario was developed from a derailment on the Union Pacific Railroad Bridge and discharging 100,000 gallons of Bakken crude oil into the Northern San Francisco Bay. The oil trajectory impacted the Carquinez Strait, Suisun, San …


Comparison Of Combustion Efficiency To In-Situ Atmospheric Ammonia Measurements From A Miniature Chemical Ionization Mass Spectrometer In The La Basin, Taylor Krause, Barry L. Lefer, Timothy H. Betram, Steven R. Schill May 2016

Comparison Of Combustion Efficiency To In-Situ Atmospheric Ammonia Measurements From A Miniature Chemical Ionization Mass Spectrometer In The La Basin, Taylor Krause, Barry L. Lefer, Timothy H. Betram, Steven R. Schill

Student Scholar Symposium Abstracts and Posters

Atmospheric ammonia (NH3) has been shown to impact the environment and threaten both human and animal health, especially in heavily populated urban areas, yet to date there remains a paucity of direct measurements. Recent studies have suggested that ammonia may be generated as a byproduct of fossil fuel emissions due to highly active catalytic converters in light-duty gasoline vehicles. To investigate this relationship, an airborne miniature Chemical Ionization Mass Spectrometer (miniCIMS) was used to directly measure atmospheric ammonia and combustion reaction products in the Southern California LA Basin, during the 2015 NASA Student Airborne Research Program (SARP). The …


The Laxarus Collection: What Has Been Found, Avonelle Combs May 2016

The Laxarus Collection: What Has Been Found, Avonelle Combs

Honors Projects

The donated Bippus collection, comprised of over 15,000 specimens of gastropods and mollusks, has mostly gone unnoticed and untouched since its donation. These collections are known as ‘orphan collections’ which escape notice and are forgotten. However, this is not the only instance in which collections are kept out of sight. Museums, whether specializing in art or natural history, display only a small portion of their entire collection at once. The majority of collections found in museums are kept out of sight from the public for various reasons. Instead of keeping the Bippus collection out of reach for both the public …


Novel Techniques In Chemical Ecology To Examine Life Histories In Fishes, Orian Tzadik Mar 2016

Novel Techniques In Chemical Ecology To Examine Life Histories In Fishes, Orian Tzadik

USF Tampa Graduate Theses and Dissertations

Diet and movements in fishes are often logistically challenging to study. Trace element and stable isotope analyses have advanced these fields considerably, but are still constrained by methodological impediments, such as the tendency towards lethal sampling. Studying endangered fishes is particularly challenging as representative samples are difficult to obtain. However, the information gained from such studies is often critical to the recovery of endangered fishes as knowledge of life history attributes has the potential to greatly influence the success of management strategies.

I tested the viability of using fin rays in fishes as a non-lethal approach to study diet and …


Acropora Habitat Evaluation And Restoration Site Selection Using A Species Distribution Modeling Approach, Katherine Wirt Ames Mar 2016

Acropora Habitat Evaluation And Restoration Site Selection Using A Species Distribution Modeling Approach, Katherine Wirt Ames

USF Tampa Graduate Theses and Dissertations

While populations of nearly all stony coral species along the Florida reef tract have exhibited decline, the most notable decline has occurred in the once-dominant acroporid species (Acropora cervicornis, A. palmata). Both species were listed in 2006 as threatened under the Endangered Species Act. This listing, combined with their continued decline, has resulted in large-scale restoration efforts throughout Florida and the Western Caribbean. Currently, there is little to no information regarding spatial prioritization of sites for these restoration efforts. The primary objective of this dissertation was to utilize species distribution modeling, informed by existing data from the …


Characterization Of Bacterial Diversity In Cold-Water Anthothelidae Corals, Stephanie Nichole Lawler Mar 2016

Characterization Of Bacterial Diversity In Cold-Water Anthothelidae Corals, Stephanie Nichole Lawler

USF Tampa Graduate Theses and Dissertations

Cold-water corals, similar to tropical corals, contain a diverse and complex microbial landscape. Comprised of vital microscopic organisms (i.e. bacteria, viruses, archaea), the coral microbiome is a driving factor in the proliferation and survival of the coral host. Bacteria provide essential biological functions within coral holobionts, facilitating increased nutrient utilization and production of antimicrobial compounds. To date, few cold-water octocoral species have been analyzed to explore the diversity and abundance of their microbial associates. For this study, 23 samples of the family Anthothelidae were collected from Norfolk (n = 12) and Baltimore Canyons (n = 11) from the western Atlantic …


Informative Spectral Bands For Remote Green Lai Estimation In C3 And C4 Crops, Oz Kira, Anthony L. Nguy-Robertson, Timothy J. Arkebauer, Raphael Linker, Anatoly A. Gitelson Jan 2016

Informative Spectral Bands For Remote Green Lai Estimation In C3 And C4 Crops, Oz Kira, Anthony L. Nguy-Robertson, Timothy J. Arkebauer, Raphael Linker, Anatoly A. Gitelson

School of Natural Resources: Faculty Publications

Green leaf area index (LAI) provides insight into the productivity, physiological and phenological status of vegetation. Measurement of spectral reflectance offers a fast and nondestructive estimation of green LAI. A number of methods have been used for the estimation of green LAI; however, the specific spectral bands employed varied widely among the methods and data used. Our objectives were (i) to find informative spectral bands retained in three types of methods, neural network (NN), partial least squares (PLS) regression and vegetation indices (VI), for estimating green LAI in maize (a C4 species) and soybean (a C3 species); (ii) to assess …


Automated Cropping Intensity Extraction From Isolines Of Wavelet Spectra, Bingwen Qiu, Zhuangzhuang Wang, Zhenghong Tang, Chongcheng Chen, Zhanling Fan, Weijiao Li Jan 2016

Automated Cropping Intensity Extraction From Isolines Of Wavelet Spectra, Bingwen Qiu, Zhuangzhuang Wang, Zhenghong Tang, Chongcheng Chen, Zhanling Fan, Weijiao Li

Community and Regional Planning Program: Faculty Scholarly and Creative Activity

Timely and accurate monitoring of cropping intensity (CI) is essential to help us understand changes in food production. This paper aims to develop an automatic Cropping Intensity extraction method based on the Isolines of Wavelet Spectra (CIIWS) with consideration of intra- class variability. The CIIWS method involves the following procedures: (1) characterizing vegetation dynamics from time–frequency dimensions through a continuous wavelet transform performed on vegetation index temporal profiles; (2) deriving three main features, the skeleton width, maximum number of strong brightness centers and the intersection of their scale intervals, through computing a series of wavelet isolines from the wavelet spectra; …


Development Of A Low-Cost Arduino-Based Sonde For Coastal Applications, Grant Lockridge, Brian Dzwonkowski, Reid Nelson, Sean P. Powers Jan 2016

Development Of A Low-Cost Arduino-Based Sonde For Coastal Applications, Grant Lockridge, Brian Dzwonkowski, Reid Nelson, Sean P. Powers

University Faculty and Staff Publications

This project addresses the need for an expansion in the monitoring of marine environments by providing a detailed description of a low cost, robust, user friendly sonde, built on Arduino Mega 2560 (Mega) and Arduino Uno (Uno) platforms. The sonde can be made without specialized tools or training and can be easily modified to meet individual application requirements. The platform allows for internal logging of multiple parameters of which conductivity, temperature, and GPS position are demonstrated. Two design configurations for different coastal hydrographic applications are highlighted to show the robust and versatile nature of this sensor platform. The initial sonde …


Hydrodynamic Variability In A Microtidal Coastal Bay Geographically Susceptible To North East Trade Winds, Israel Medina-Gómez, Cecilia Enríquez, Björn Kjerfve, Ismael Mariño, Jorge Herrera-Silveira Jan 2016

Hydrodynamic Variability In A Microtidal Coastal Bay Geographically Susceptible To North East Trade Winds, Israel Medina-Gómez, Cecilia Enríquez, Björn Kjerfve, Ismael Mariño, Jorge Herrera-Silveira

Gulf and Caribbean Research

The ecological integrity and overall health conditions of natural coastal systems are largely based upon the balance among physical processes. The objective of this study was to assess the effects of tides and winds on the water level variability, circulation patterns, and turnover time in Bahia de la Ascension (BA), a shallow, tropical coastal bay in the Mexican Caribbean prone to the influence of Trade winds due to its geographical location. The analysis of the hydrodynamics of BA using a 2D numerical model indicates that the tidal flow in the inlets and central basin of the bay vary by tidal …


Odu, William & Mary Seek Funds For Joint Center On Sea-Level Rise, Dave Mayfield Dec 2015

Odu, William & Mary Seek Funds For Joint Center On Sea-Level Rise, Dave Mayfield

News Items

No abstract provided.


Comparison Of Otolith-Based Growth Rates And Microchemistry In Red Drum Before, During, And After The Deepwater Horizon Oil Spill, Brock Charles Houston Nov 2015

Comparison Of Otolith-Based Growth Rates And Microchemistry In Red Drum Before, During, And After The Deepwater Horizon Oil Spill, Brock Charles Houston

USF Tampa Graduate Theses and Dissertations

Oil from the Deepwater Horizon blowout reached the Gulf of Mexico coast in the summer of 2010 and potentially exposed species living in those areas to toxic chemicals. The purpose of this study is to examine otoliths from Red Drum (Sciaenops ocellatus) for evidence of oil exposure that could be related to reduced growth rates. Because otolith growth and somatic growth are directly related, differences in annulus measurements can indicate differences in annual somatic growth, which is a good indicator of overall fish condition, and translates into changes in survival and lifetime reproductive potential. This study assessed variation …


The Development Of A Fluorescence-Based Reverse Flow Injection Analysis (Rfia) Method For Quantifying Ammonium At Nanomolar Concentrations In Oligotrophic Seawater, William Abbott Nov 2015

The Development Of A Fluorescence-Based Reverse Flow Injection Analysis (Rfia) Method For Quantifying Ammonium At Nanomolar Concentrations In Oligotrophic Seawater, William Abbott

USF Tampa Graduate Theses and Dissertations

The goal of this thesis was to adopt a reverse flow injection analysis (rFIA) technique to the fluorometric analysis of the reaction o-phthaldialdehyde (OPA) with ammonium, allowing accurate measurements of ammonium concentrations lower than the detection limit of the widely used indophenol blue (IPB) colorimetric method while accounting for the background fluorescence of seawater. Ammonium is considered an essential nutrient for primary productivity, especially in the nutrient depleted surface ocean where as the most reduced form of dissolved inorganic nitrogen, it is readily assimilated via metabolic pathways. Challenges in the quantification of ammonium require more sensitive analytical techniques for …


Influence Of Water Column Stratification And Nutrient Gradients On The Migratory Behavior Of The Red Tide Dinoflagellate, Karenia Brevis, Matthew Garrett Nov 2015

Influence Of Water Column Stratification And Nutrient Gradients On The Migratory Behavior Of The Red Tide Dinoflagellate, Karenia Brevis, Matthew Garrett

USF Tampa Graduate Theses and Dissertations

Diel vertical migration (DVM) can offer motile phytoplankton a competitive advantage over other phytoplankton species. DVM has been well documented in the harmful dinoflagellate, Karenia brevis; however, the extent to which changes in nutrient regimes and density stratification modify migration patterns has not been thoroughly investigated. A 2 m experimental column was constructed with sensors and sampling ports at four depths to obtain fluorescence and temperature measurements and discrete water samples. The environmental parameters of the experimental column represented temperature and nutrient conditions found on the West Florida Shelf (WFS), where Karenia blooms frequently occur. Results demonstrated a clear …


Dissolved Nutrient Distributions In The Gulf Of Mexico Following The Deepwater Horizon Oil Spill, Ashley Ann Parks Oct 2015

Dissolved Nutrient Distributions In The Gulf Of Mexico Following The Deepwater Horizon Oil Spill, Ashley Ann Parks

USF Tampa Graduate Theses and Dissertations

The Deepwater Horizon (DWH) oil spill in the Gulf of Mexico (GoM) in the spring of 2010 introduced 4.4 million of barrels of oil to the ecosystem. Some biodegradation of the oil occurs when microorganisms, particularly bacteria, metabolize the oil as a carbon source. During this process, the microbes also require nutrients for energy. An introduction of oil at this magnitude has the ability to induce large blooms of microbes, which in turn can affect nutrient concentrations. Microbial petroleum degradation decreases nutrient concentrations, whereas the microbial assimilation and decay of organic matter increase nutrient concentrations. This study assessed whether any …


Temporal Variation In Optical Properties Of Chromophoric Dissolved Organic Matter (Cdom) In Southern California Coastal Waters With Nearshore Kelp And Seagrass, Catherine D. Clark, Warren J. De Bruyn, Paige Aiona Oct 2015

Temporal Variation In Optical Properties Of Chromophoric Dissolved Organic Matter (Cdom) In Southern California Coastal Waters With Nearshore Kelp And Seagrass, Catherine D. Clark, Warren J. De Bruyn, Paige Aiona

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Optical properties of chromophoric dissolved organic matter (CDOM) were measured in surf zone waters in diurnal field studies at a Southern California beach with nearshore kelp and seagrass beds and intertidal plant wrack. Absorption coefficients (aCDOM(300 nm)) ranged from 0.35 m21 to 3.7 m21 with short-term variability<1 h, increases at ebb and flood tides and higher values (6 m21) during an offshore storm event. Spectral slopes (S) ranged from 0.0028 nm21 to 0.017 nm21, with higher values after the storm; S was generally inversely correlated with aCDOM(300 nm). 3-D excitation–emission matrix spectra (EEMs) for samples with lower S values had humic-type peaks associated with terrestrial material (A, C), marine microbial material (M) and protein peaks, characteristic of freshly produced organic material. Samples with high S values had no or reduced protein peaks, consistent with aged material. Fluorescent indexes (f450/f500 >2.5, BIX>1.1) were consistent with microbial aquatic sources. Leachates of senescent kelp and seagrass had protein and humic-type EEM peaks. After solar simulator irradiation (4 h), protein peaks rapidly photochemically degraded, humic-type peak C increased in intensity and peak M disappeared. Optical characteristics of kelp leachates were most similar to field samples, …


Aulacoseira Stevensiae Sp. Nov. (Coscinodiscophyceae, Bacillariophyta), A New Diatom From Ho Ba Bê, Bac Kan Province, Northern Viêt Nam, D. Marie Weide Oct 2015

Aulacoseira Stevensiae Sp. Nov. (Coscinodiscophyceae, Bacillariophyta), A New Diatom From Ho Ba Bê, Bac Kan Province, Northern Viêt Nam, D. Marie Weide

Department of Earth and Atmospheric Sciences: Faculty Publications

A new species of Aulacoseira Thwaites is described from piston core samples from Ho Ba Bê in the karst region of northern Viêt Nam. Although it closely resembles Aulacoaseira subborealis (Nygaard) Denys, Muylaert & Krammer, A. stevensiae Weide sp. nov. is designated a new species based mainly on morphological differences in the spines, including invariably inclined spines that are rounded, differences in the Ringleiste, areola pattern and overall size. Aulacoseira stevensiae is present throughout a core that spans the last 500 years. It was a major component of the diatom community, but the populations have recently decreased, possibly being outcompeted …


Field Observations And Novel Methodologies For Carbon System Assessments In Coastal Waters, Bo Yang Sep 2015

Field Observations And Novel Methodologies For Carbon System Assessments In Coastal Waters, Bo Yang

USF Tampa Graduate Theses and Dissertations

Coastal zones receive massive terrestrial inputs of nutrients and organic matter, and play an important role in biogeochemical cycles. The interactions of river inputs, ocean currents, atmospheric exchanges, anthropogenic influences, and biologically active ecosystems make CO2 system studies in coastal waters highly challenging. This work focuses on improving our understanding of the CO2 system in coastal waters through (1) development of a new methodology for measurements of CO2 system parameters in the field; (2) observations of large spatial and temporal CO2 system variations in coastal waters; and (3) characterization of the influence of organics on CO …


Techniques For Payload Stabilization For Improved Photography During Stratospheric Balloon Flights, James Flaten, Christopher Gosch, Joseph (Benjamin) Habeck Jun 2015

Techniques For Payload Stabilization For Improved Photography During Stratospheric Balloon Flights, James Flaten, Christopher Gosch, Joseph (Benjamin) Habeck

2017 Academic High Altitude Conference

Payload-box rotation and swing are perennial challenges to achieving high-quality photography (typically videography) during weather-balloon flights to “near-space” (AKA the stratosphere). Continuous camera motion can lead to blurred still photos, nearly-impossible-to-watch video footage, and precludes time-exposure photography required for most astronomical imaging even though altitudes are reached where the daytime sky appears black. Apparently-random payload rotation, persisting even at altitude, can often exceed servo rotation rates and frustrate attempts to do active camera pointing. Here we discuss mostly-passive payload stabilization strategies we, and our collaborators, have used to mitigate and dampen both swing and rotation of suspended payloads on high-altitude …