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Field patterns and experimental results suggest that the effect of zooplankton grazing on the abundance of large colonial cyanobacteria may differ strongly from case to case. In this article we present an extensive analysis of a model that describes the competition between cyanobacteria of the Oscillatoria group and green algae exploited by Daphnia. In particular, we study the response of the model to changes in the nutrient concentration and predation by zooplanktivorous fish. The analysis is repeated for an array of different assumptions on the nutritional value of cyanobacteria and selectivity of zooplankton grazing. When fish predation pressure is so high that Daphnia density is negligible, there is competitive...
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This U.S. Geological Survey (USGS) Data Release provides phytoplankton data for samples collected from eleven large river sites throughout the United States, from June through September 2017. All data are reported as raw calculated values and are not rounded to USGS significant figures. The dataset includes all routine and quality assurance/quality control samples collected as part of a National Water Quality Assessment Project pilot study to describe the potential for cyanobacteria and cyanotoxin occurrence in the Nation's large rivers. Phytoplankton were identified to the lowest possible taxonomic level and abundances (density reported as natural units) are reported.
Categories: Data; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Algae, California, Chattahoochee River near Whitesburg, GA, Connecticut, Connecticut River at Thompsonville, CT, All tags...
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The data were collected at Morley Nelson, Birds of Prey National Conservation Area (NCA) where known grazing regimes, including the season of grazing, have been in practice for the last 30 years. Surveyed plots were placed to account for intensity of grazing and to avoid confounding disturbances. Data were collected on the morphogroups of biological soil crusts (biocrusts) found within the NCA, and include measurements on soils related to texture, carbon, nitrogen and the abundance of soil aggregating cyanobacteria in the soil. These data support the following publication: Condon, L.A., Rosentreter, R., Veblen, K.E. and Coates, P.S., 2024. Season of grazing interacts with soil texture, selecting for associations...
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This child item data set provides phytoplankton data collected from Seneca Lake, New York between October 9-10, 2019. Phytoplankton were identified to the lowest possible taxonomic level, and abundance (density reported as both natural units and cells) and biovolume are reported. All data are reported as raw calculated values. This dataset includes all routine and quality assurance/quality control samples collected at twelve sampling locations on Seneca Lake.
Categories: Data; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: Class, Contaminants, HABS, Division, Family, Finger Lakes, All tags...
We describe a population of colonial cyanobacteria (waterwarts) that develops as the dominant primary producer in a bottom-fed, O2-poor, warm spring in the Cuatro Ci�negas karstic region of the Mexican Chihuahuan Desert. The centimeter-sized waterwarts were suspended within a central, conically shaped, 6-m deep well by upwelling waters. Waterwarts were built by an Aphanothece-like unicellular cyanobacterium and supported a community of epiphytic filamentous cyanobacteria and diatoms but were free of heterotrophic bacteria inside. Sequence analysis of 16S rRNA genes revealed that this cyanobacterium is only distantly related to several strains of other unicellular cyanobacteria (Merismopedia, Cyanothece, Microcystis)....
In both field and greenhouse studies, cyanobacterial and cyanolichens of cold-temperature deserts often enhance growth and essential uptake by associated herbs. That effect is associated with better seedling establishment and larger seedlings. The following are possible mechanisms for these effects: (1) the microbiota concentrate essential elements in available forms in soil surface layers, (2) the microbial surface covers are usually darker colored than the soil itself and produce warmer soils during cool seasons when soil water is most available, (3) the gelatinous sheaths of several cyanobacterial genera common on alkaline deserts contain chelating compounds, and (4) conditions that favor persistent microbial...
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In cooperation with the Texas Commission on Environmental Quality (TCEQ), the U.S. Geological Survey (USGS) used various field and laboratory methods to determine the presence and concentration of cyanobacteria, cyanotoxins, and taste-and-odor compounds in selected Texas water bodies. This data release documents the results from water-quality samples collected from 12 water bodies in Texas during water year 2020 (WY20) and 2021 (WY21). A water year is defined as the 12-month period from October 1 through September 30 and is designated by the calendar year in which it ends. Both qualitative and quantitative field and laboratory methods were performed. Analyses included phytoplankton taxonomy, measurements of phytoplankton...
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This U.S. Geological Survey (USGS) Data Release provides the phytoplankton tally sheet, including photomicrographs, for samples collected from eleven large river sites throughout the United States, from June through September 2017. All data are raw tallies, not calculated abundances or concentrations. The dataset includes all routine and quality assurance/quality control samples collected as part of a National Water Quality Assessment Project pilot study to describe the potential for cyanobacteria and cyanotoxin ocurrence in the Nation's large rivers. Phytoplankton were identified to the lowest possible taxonomic level and abundances (density reported as natural units) are reported.
Categories: Data; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Algae, California, Chattahoochee River near Whitesburg, GA, Connecticut, Connecticut River at Thompsonville, CT, All tags...
The articles in this issue of the Canadian Journal of Botany arose from presentations given at The Fifth International Symposium on Inorganic Carbon Utilization by Aquatic Photosynthetic Organisms held from 24 to 28 August 2004 at Saint-Sauveur, Quebec, Canada. They represent the current state of our understanding of CO2-concentrating mechanisms in these organisms and highlight recent molecular, physiological, and ecological advances made in this field of study. The influence of CO2-concentrating mechanisms on global carbon sequestration, species diversity, and population dynamics are also explored.Key words: algae, CO2-concentrating mechanisms, cyanobacteria, photosynthesis.Les articles dans ce numéro de la Revue...
The effect of solar radiation and monochromatic UV radiation on the motility of the filamentous cyanobacterium Phormidium uncinatum was determined. Solar radiation (mid-day, in midsummer at a location near Lisboa, Portugal) was found to impair motility within about 30 min. This effect is neither a result of a temperature increase nor of visible light. The spectral sensitivity determined using the Okazaki Large Spectrograph shows the maximal effectiveness of radiation of ^300 nm. The short time requirement for the response and the lack of any photoreactivation of motility argues against DNA being the UV target. Investigations using reagents diagnostic of superoxide free radicals and singlet oxygen failed to confirm...
This study describes the toxic effects of different prominent aquatic pollutants?heavy metals (Cd & Pb), pesticides (alphamethrin and deltamethrin) and salt (NaCl)?on the intracellular proline content in the cyanobacterium, Westiellopsis prolifica?Janet strain?NCCU331. Despite a reduction in growth (measured as chlorophyll a content), the intracellular proline content increased in the presence of heavy metals, pesticides and high salt concentration. The intracellular cyanobacterial proline accumulation was more pronounced under salt stress than in the presence of pesticides and heavy metals. We have also compared whether or not anionic components influence heavy metal toxicity. It was found that the chlorides of...
Biological soil crusts are key mediators of carbon and nitrogen inputs for arid land soils and often represent a dominant portion of the soil surface cover in arid lands. Free-living soil nematode communities reflect their environment and have been used as biological indicators of soil condition. In this study, we test the hypothesis that nematode communities are successionally more mature beneath well-developed, late-successional stage crusts than immature, early-successional stage crusts. We identified and enumerated nematodes by genus from beneath early- and late-stage crusts from both the Colorado Plateau, Utah (cool, winter rain desert) and Chihuahuan Desert, New Mexico (hot, summer rain desert) at 0?10 and...
Reactive oxygen species (ROS) are involved in the oxidative damage of the cyanobacterium Anabaena sp. caused by UV-B (280?315 nm) radiation. UV-B-induced overproduction of ROS as well as the oxidative stress was detected in vivo by using the ROS-sensitive probe 2?,7?-dichlorodihydrofluorescein diacetate (DCFH-DA). Thiobarbituric acid reactive substances (TBARS) and fluorometric analysis of DNA unwinding (FADU) methods were adapted to measure lipid peroxidation and DNA strand breaks in Anabaena sp. Moderate UV-B radiation causes an increase of ROS production, enhanced lipid peroxidation and DNA strand breaks, yielding a significantly decreased survival. In contrast, the supplementation of UV-A in our work only showed...
Field patterns and experimental results suggest that the effect of zooplankton grazing on the abundance of large colonial cyanobacteria may differ strongly from case to case. In this article we present an extensive analysis of a model that describes the competition between cyanobacteria of the Oscillatoria group and green algae exploited by Daphnia. In particular, we study the response of the model to changes in the nutrient concentration and predation by zooplanktivorous fish. The analysis is repeated for an array of different assumptions on the nutritional value of cyanobacteria and selectivity of zooplankton grazing. When fish predation pressure is so high that Daphnia density is negligible, there is competitive...
Cyanobacteria develop as large, cryptic populations in the topsoil of arid land, where plant cover is restricted, water is scarce and harsh microenvironmental conditions prevail. Here we show that some cyanobacteria can actively move in response to wetting or drying events by migrating to the soil surface or retreating to their refuge below. This ability to follow water, which to our knowledge has not been demonstrated before in microbes, may turn out to be important for microbial terrestrial populations in general. Published in Nature, volume 413, issue 6854, on pages 380 - 1, in 2001.
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This dataset is a collection of hyperspectral imagery profiles of 13 common algae associated with Harmful Algae Blooms (HAB). Data were retrieved from a hyperspectral microscope at, and with the cooperation of, the National Institute of Standards and Technology. Samples were collected from USGS water quality sampling efforts, and were also purchased from commercial vendors of biological materials. Data are shown in basic hyperspectral imagery form, transformed into the first derivative and corrected with a flat field algorithm to account for variations in locale lighting conditions. First posted - January 6, 2020 (available from author) Revised - October 30, 2020 (version 2.0)
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Field data for vertical profiles of light and water quality parameters were collected biweekly between May and November in 2019 and June and October in 2020 in association with continuous monitoring platforms in Owasco, Seneca, and Skaneateles Lakes, Finger Lakes Region, New York. Water quality profiles were collected using Yellow Spring Instruments (YSI) EXO2 sondes and light profiles were collected using a LI-COR Photosynthetically Active Radiation (PAR) sensor in 2019 and Onset HOBO Pendant Temperature and Light data loggers in 2020. This data release includes all measured environmental parameters included in the analysis. This data release was produced in compliance with the open data requirements as a way...
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We have analyzed the solvent extracts from three different types of native bitumens from the Uinta Basin in northeastern Utah by a variety of analytical techniques, including GC-IRMS, to evaluate variations in the paleodepositional environment during two periods of Lake Uinta deposition. The gilsonite and tabbyite bitumens are associated with Parachute Creek Member sediments deposited during a major expansion of ancient Lake Uinta. Compound specific isotopic analyses of ß-carotane and phytane (δ 13C = −32.6 to −32.1%0) from these bitumens reflect input from primary photosynthetic producers such as cyanobacteria. Sterane δ 13C values (−34.5 to −29.2%0) refflect contributions from lacustrine algae, while extremely...
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Spatial reconnaissance of fluvial microcystins (MC) concentrations and select water-quality parameters, including nutrients and periphyton biomass, in 75 wadeable streams in the Piedmont region of the southeastern USA during 2014. Data set includes only those data specifically discussed in the associated journal article: Loftin, K.A., Clark, J.M., Journey, C.A., Kolpin, D.W., Van Metre, P.C., and Bradley, P.M., 2016, Spatial and temporal variation in microcystins occurrence in wadeable streams in the southeastern USA: Environmental Toxicology & Chemistry, http://dx.doi.org/10.1002/etc.3391.
Reactive oxygen species (ROS) are involved the damage of living organisms under environmental stress including UV radiation. Cyanobacteria, photoautotrophic prokaryotic organisms, also suffer from increasing UV-B due to the depletion of the stratospheric ozone layer. The increased UV-B induces the production of ROS in vivo detected by using the ROS-sensitive probe 2?,7?-dichlorodihydrofluorescein diacetate (DCFH-DA). Ascorbic acid and N-acetyl- -cysteine (NAC) scavenged ROS effectively, while ?-tocopherol acetate or pyrrolidine dithiocarbamate (PDTC) did not. The presence of rose bengal and hypocrellin A increased the ROS level by photodynamic action in the visible light. The presence of the herbicide, 3-(3,4-dichlorophenyl)-1,1-dimethyl...
map background search result map search result map Compound specific isotopic variability in Uinta Basin native bitumens: paleoenvironmental implications Periphyton (1993-2011) and Water Quality (2014) Data for ET&C Article Entitled Spatial and Temporal Variation in Microcystins Occurrence in Wadeable Streams in the Southeastern USA Phytoplankton data for samples collected at eleven large river sites throughout the United States, June through September 2017 Phytoplankton tally sheet, including photomicrographs, for samples collected at eleven large river sites throughout the United States, June through September 2017 Hyperspectral Characterization of Common Cyanobacteria Associated with Harmful Algal Blooms (ver. 2.0, October 2020) Vertical Profiles of Water Quality and Light in Owasco, Seneca, and Skaneateles Lakes, Finger Lakes Region, New York, 2019-2020 Seneca Lake, New York phytoplankton data, October 9-10, 2019 Assessment of Field and Laboratory Methods for the Detection and Analyses of Cyanobacteria and Cyanotoxins in Texas Reservoirs, 2020 Morphogroups of Biocrusts Following Seasons of Grazing Near Boise, Idaho Hyperspectral Characterization of Common Cyanobacteria Associated with Harmful Algal Blooms (ver. 2.0, October 2020) Seneca Lake, New York phytoplankton data, October 9-10, 2019 Morphogroups of Biocrusts Following Seasons of Grazing Near Boise, Idaho Vertical Profiles of Water Quality and Light in Owasco, Seneca, and Skaneateles Lakes, Finger Lakes Region, New York, 2019-2020 Compound specific isotopic variability in Uinta Basin native bitumens: paleoenvironmental implications Periphyton (1993-2011) and Water Quality (2014) Data for ET&C Article Entitled Spatial and Temporal Variation in Microcystins Occurrence in Wadeable Streams in the Southeastern USA Assessment of Field and Laboratory Methods for the Detection and Analyses of Cyanobacteria and Cyanotoxins in Texas Reservoirs, 2020 Phytoplankton data for samples collected at eleven large river sites throughout the United States, June through September 2017 Phytoplankton tally sheet, including photomicrographs, for samples collected at eleven large river sites throughout the United States, June through September 2017