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Exploring Algaecide Effectiveness in the Benthic Cyanobacteria CommunityWinkler, Kristina E. 12 June 2018 (has links)
No description available.
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The Distribution of Dinoflagellate Cysts along the West Florida Coast (WFC)Kang, Yoonja 01 January 2010 (has links)
Harmful algal blooms (HABs) along the Florida coast have been reported for many decades. Karenia brevis is a red tide species on the West Florida Shelf, producing a suite of toxins called brevetoxins that adversely affect marine organisms and humans. Dinoflagellate cysts have been studied as a tool for red tide studies since the location where cysts accumulate in the sediments and the size of the seed beds can be important for potential blooms. However, little attention has been paid on the dinoflagellate cysts on the West Florida Coast. This study describes the distribution of dinoflagellate cysts along the West Florida Coast and proposes the possibility of Karenia brevis cysts. Samples were collected with a box corer July 17-29 and October 5-17, 2009. Overall cyst concentrations are low. The sediments along the West Florida Coast compose of coarse-sized grains that generate large-sized pores. Thus, cysts in the coarse-grained sediments might easily move along with turbulence or water movements flowing above the sediments. Cyst concentrations gradually increased shoreward. The hydrographic features along the West Florida Coast are influenced by the coastal current. Southward coastal current flowed during two cruises might drive a subsequent offshore Ekman transport which might lead to a coastal upwelling, thereby transporting bottom sediments closer to the coast. Thus, cyst concentration was higher inshore compared to that offshore. The average concentration of heterotrophic dinoflagellate cysts was higher in July than that in October, whereas autotrophic dinoflagellate cysts did not have a noticeable difference between July and October. The heterotrophic group is dominated by a protoperidinioid group that mainly feeds on diatoms. The abundance of protoperidinioid was higher in July than in October and other groups have similar abundance between two periods. The highest abundance of diatoms is in June, July and August, whereas the lowest was in October, November and May. Therefore, the decrease in the abundance of protoperidinioid cysts correlates with the lower food supply for their motile cells. Based on a morphological similarity to a Karenia brevis cyst detected in culture by Walker (1982) and a morphological difference from other species belonging to the same genus, cysts that are probably Karenia brevis have been identified.
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The HABS Culture of Documentation with an Analysis of Drawing and TechnologyAkboy, Serra 2011 December 1900 (has links)
The Historic American Buildings Survey (HABS) is one of the oldest federal programs in the United States. In 1933, the HABS culture of documentation started with the mission of creating a permanent record of the nation's architectural heritage. Since the inception of the program, the formal documentation methodology has been measured drawings, large-format photographs, and written histories. HABS documentation accentuates the act of drawing as a mediating conversation between the documenter and the historic environment. In a typical HABS project, the documenter is immersed in the historic setting by hand measuring the structure and creating field notes. The documenter's intimate access to the artifact develops his awareness of cultural heritage and helps cultivate an appreciation for the compositional sensibilities of the architectural precedents. However, the HABS culture of documentation has been fine-tuned to incorporate a number of digital technologies into documentation projects. When projects involve issues of logistics, time, and cost, HABS professionals utilize a host of digital methodologies to produce measured drawings. Although HABS prepares deliverables to meet the archival standards of the Library of Congress, the hardware and software necessary to recognize digital files have a limited lifespan that makes them unacceptable for use in the Library. Only measured drawings that use archival ink on stable translucent material, accompanied by negatives on safety film, can be submitted to the Library. Thus, if HABS pursued only digital technologies and deliverables, the effects of this approach on the quality of the documenter's engagement with cultural heritage would pose a significant question.
This study addressed the question of how the HABS culture of documentation evolved in regards to drawing and technology, and how this relationship might be transformed in the future. Using HABS as a focus of inquiry is important in order to illuminate similar dynamics in heritage projects that utilize digital technologies. The methodology used in this study included a literature review, participant observations, and an analysis of documentation projects, as well as in-depth interviews with HABS staff, project participants, private practitioners, and academicians. The outcome of the study will be recommendations to heritage professionals for a future that resides in digital means without compromising the qualities that the HABS experience has offered to generation of documenters.
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UNDERSTANDING SPATIOTEMPORAL PATTERNS OF HARMFUL ALGAL BLOOMS: A CITIZEN SCIENCE PERSPECTIVELefaivre, Ryan 01 August 2023 (has links) (PDF)
Harmful Algal Blooms (HABs) occur due to the excessive growth of algal in waterbodies such as lakes, rivers, and ponds. The cyanotoxins produced by HABs are harmful to wildlife, animals, and humans when ingested or exposed. Due to the toxic and rapid growth of HABs, it is essential to assess potential causes of HABs over broad geographical scales. This observational study aims to understand the spatiotemporal patterns and drivers of HABs across the State of Illinois using both regular environmental monitoring and citizen science datasets from the Illinois Environmental Protection Agency (IEPA). The Ambient Lake Monitoring Program and the Illinois Clean Lakes Program regularly conduct chlorophyll-a measurements, collectively referred to as the ALMP + ICLP dataset. Similarly, the Volunteer Lake Monitoring Program of the Illinois Environmental Protection Agency (IEPA) organizes volunteer citizens to collect Secchi-disk measurements, known as the VLMP dataset. Machine learning algorithms including Random Forest, Artificial Neural Network, and Support Vector Machine are used to evaluate HABs and trophic states of HABs based on nine meteorological variables, six lake morphological variables, and eight land use and land cover variables. The data characteristics found the Cook county area consisted of over half of the total VLMP observations. The meteorological variables were most important for accuracy and classification in the Random Forest modeling, and the VLMP dataset performed the best at trophic state classification, and the Random Forest model performed the best overall compared to the other machine learning models. This study concludes that the VLMP is a beneficial and comparable tool when coupled with the ALMP + ICLP data for HAB monitoring in Illinois.
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LISST Instruments as a Tool in Phytoplankton EcologyRailey, Lauren 1987- 14 March 2013 (has links)
Laser in situ scattering and transmissometry (LISST) instruments are used to measure the particle size distributions (PSDs) and volume concentration of individual and groups of phytoplankton in water. The objective of this research was to test the LISST’s ability in detecting monospecific blooms in-situ and the ability to detect aggregation after diatoms were subjected to different temperatures and bacteria concentrations. The PSDs of ten harmful algal bloom (HAB) species were measured with the LISST characterizing the peak location, peak height, peak width, and peak range resulting in a scattering signature for each species. Each species had specific characteristics that would allow for their detection with the LISST, though microscope observations would be needed for complete accuracy. The LISST was able to detect HABs placed in natural seawater collected off the Texas coast. Blooms of four HAB species before they reached full” bloom concentrations were detected making the LISST a possible low cost, effective tool in the early detection and monitoring of HABs. The diatom, Odontella aurita, was used to test how well the LISST could monitor aggregation, an important process in the termination of many phytoplankton blooms. Increasing temperature causes an increase in transparent exopolymer particle (TEP) production in diatoms, which is a critical sticky particle that increases the probability of aggregation. An increase in temperature can also cause an increase in bacteria concentration that can positively effect TEP production and thus aggregation. O. aurita was grown at 20 °C and 28 °C and showed a significant increase in TEP abundance with temperature (p = 0.002), though no relationship between TEP production and bacteria concentration existed. Coomassie stained particles (CSP) are proteinaceous gel-like particles, which are currently understudied. CSP was consistently produced though it did not appear to be dependent upon any single factor. The increase in ocean temperatures has implications for an increase in phytoplankton blooms making the monitoring and understanding of these blooms even more important as they can affect the carbon cycle and potentially the microbial loop.
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Brevetoxin Body Burdens in Seabirds of Southwest FloridaAtwood, Karen E 28 March 2008 (has links)
Harmful algal blooms (HABs, or "red tides") of the brevetoxin-producing dinoflagellate Karenia brevis occur periodically along Florida's Gulf coast. Mass mortalities of marine birds have long been associated with these blooms, yet there are few data documenting the accumulation of brevetoxins (PbTx) in the tissues of birds.
Post-mortem evaluations were performed on 185 birds representing 22 species collected from October 2001 through May 2006 during red tide and non-red tide events to quantify their body burdens of brevetoxins. A variety of tissues and organs were selected for brevetoxin analysis including blood, brain, heart, fat, stomach or gut contents, intestinal contents or digestive tract, muscle, lung, liver or viscera, kidney, gonads, gallbladder and spleen. Brevetoxin levels in avian tissues ranged from K. brevis which may amass in various tissues of the body. As a consequence, the birds may exhibit acute brevetoxicosis during red tide events or show chronic accumulation effects during non-red tide events.
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Applications of Mass Spectrometry for Qualitative Analysis and Imaging of Microcystins in Mouse Tissues, Cyanobacterial Cells and WaterKucheriavaia, Daria January 2020 (has links)
No description available.
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Mitigating Harmful Algal Blooms using a Robot SwarmSchroeder, Adam January 2018 (has links)
No description available.
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Impacts of Potassium permanganate pre-oxidation on cell integrity, organic matter, and AOC release of Microcystis aeruginosaKadudula, Anusha January 2020 (has links)
No description available.
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Landsat Collections Reveal Long-Term Algal Bloom Hot Spots of Utah LakeTate, Rachel Shanae 01 July 2019 (has links)
Harmful algal blooms (HABs) and nuisance algal blooms (NABs) are a worldwide phenomenon with implications for human health and safety. HABs occur when algae or bacteria grow in high enough densities to harm animals and humans. A primary component of harmful algal blooms is cyanobacteria, which are aquatic, photosynthesizing microorganisms that produce toxins at high concentrations. Cyanobacterial biomass has increased worldwide in recent decades, raising concern about the future of fresh- and marine-water systems in a changing climate. Understanding the patterns and conditions of past algal blooms can provide useful insights for managing future blooms. Remote sensing can enhance our understanding of the spatiotemporal distribution of HABs and NABs. We used radiometrically corrected images from the USGS Landsat Collections available in the Google Earth Engine for cloud processing. In 2016, the USGS calibrated the sensors of Landsat 4, 5, 7, and 8 to create a continuous collection of satellite images from 1984 to present. We use this 34-year dataset to expand the historical record of algal blooms at our study site and to understand factors relating to the spatiotemporal patterns of these blooms. We applied three models, including the Floating Algae Index (FAI), the Normalized Difference Vegetation Index (NDVI), and one developed with in situ chlorophyll-a (chl-a) data, to 398 images masked for cloud cover and lake elevation taken from 34 growing seasons (April – October). We found that the Normalized Difference Water Index (NDWI) used to separate water and land pixels fails under algal bloom conditions, whereas a modified NDWI does not. We also performed an emerging hot spot analysis in ArcGIS using the chlorophyll-a, NDVI, and FAI predictions from the surface reflectance values of the images. Our analysis indicates that the Provo Bay and parts of the eastern shoreline of Utah Lake have had algal blooms for 30 out of the 34 years included in this study, rendering them enduring hot spots. The remainder of the lake is a cold spot, showing clusters of low mean chl-a, NDVI, and FAI values over time. The overall trend of mean NDVI and lake surface area over this 34-year dataset is decreasing, whereas lake water temperature is increasing. This study develops a method for analyzing algal blooms over multiple decades and provides useful information for the management and prediction of future blooms.
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