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Rainfall simulation experiments were performed on 25 plots of varying microphytic crust cover in a wooded semiarid rangeland in eastern Australia. Under a rainfall intensity of 45 mm h-1, steady-state infiltration ranged from 5 mm h-1 to 41 mm h-1, but there was no effect of cover on this or any of the other soil hydrological variables measured. When disturbed plots with low cover (<15% cover) were excluded from the analyses, significant increases in time to ponding were associated with increases in crust cover. Despite some significant relationships, however, crust cover was an insignificant predictor of soil hydrological status at this site. We attribute this to the well-structured nature of the soils at the site,...
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For State agencies and other water-resources managers, determining which waterbodies to allocate limited funds for protection and restoration while also maximizing cost benefit is challenging. This data release contains trophic state designations determined from secchi depth, and concentrations of chlorophyll a and microcystin at 232 lakes and reservoirs having a surface area of greater than 0.1 square kilometer in watersheds that drain to the Atlantic and eastern Gulf of Mexico coasts of the United States and in watersheds within the Tennessee River Basin. Estimates of nutrient loading (nitrogen and phosphorus, Hoos and others, 2013; Moorman and others, 2014) and flushing rates were combined with waterbody morphometry...
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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 October 2018. 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 cyanobacteria and cyanotoxin occurrence in the Nation's large rivers. Phytoplankton were identified to the lowest possible taxonomic level and abundance (reported as both natural units and cells) is reported.
Categories: Data; Tags: Algae, Aquatic Biology, California, Chattahoochee River near Whitesburg, GA, Connecticut, All tags...
We analyzed the microtopography of microbiotic soil crusts at 3 sites on the Colorado Plateau of southern Utah and investigated distributions of cyanobacteria and several lichens in distinctive microhabitats created by this topography. At all 3 sites the long axes of linear soil mounds were oriented nonrandomly in a NNW?SSE direction. The conspicuous and consistent orientation of soil mounds may result from a combination of physical and biotic processes. Subtle differences across sites in mound orientation and organismal distribution suggest that these variables may be useful in comparing disturbance histories of crusts retrospectively. Differences in colonization frequencies, abundances, and distributions of microorganisms...
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Recently disturbed and ‘control’ (i.e. less recently disturbed) soils in the Mojave Desert were compared for their vulnerability to wind erosion, using a wind tunnel, before and after being experimentally trampled. Before trampling, control sites had greater cyanobacterial biomass, soil surface stability, threshold friction velocities (TFV; i.e. the wind speed required to move soil particles), and sediment yield than sites that had been more recently disturbed by military manoeuvres. After trampling, all sites showed a large drop in TFVs and a concomitant increase in sediment yield. Simple correlation analyses showed that the decline in TFVs and the rise in sediment yield were significantly related to cyanobacterial...
Phenotype and molecular approaches were applied to the study diversity of 14 original soil Nostoc strains. Obtained data were compared with other molecular and phenotypic data of soil and symbiotic strains. Morphology of cells, filaments, hormogonia and mucilaginous sheaths were observed. Special attention was paid to life cycles. Considerable variability was found by both (the molecular and the morphological) approaches. Nine clusters sharing similarity of 95% were obtained analysing 87 16S rDNA Nostoc sequences. In some of them a significant correlation between results of molecular and morphological approach was found. Published in Algological Studies, volume 117, issue 1, on pages 251 - 264, in 2005.
Soil erosion and subsequent degradation has been a contributor to societal collapse in the past and is one of the major expressions of desertification in arid regions. The revised universal soil loss equation (RUSLE) models soil lost to water erosion as a function of climate erosivity (the degree to which rainfall can result in erosion), topography, soil erodibility, and land use/management. The soil erodibility factor (K) is primarily based upon inherent soil properties (those which change slowly or not at all) such as soil texture and organic matter content, while the cover/management factor (C) is based on several parameters including biological soil crust (BSC) cover. We examined the effect of two more precise...
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Biological soil crusts (BSCs), a consortium of cyanobacteria, lichens, and mosses, are essential in most dryland ecosystems. As these organisms are relatively immobile and occur on the soil surface, they are exposed to high levels of ultraviolet (UV) radiation and atmospheric nitrogen (N) deposition, rising temperatures, and alterations in precipitation patterns. In this study, we applied treatments to three types of BSCs (early, medium, and late successional) over three time periods (spring, summer, and spring–fall). In the first year, we augmented UV and altered precipitation patterns, and in the second year, we augmented UV and N. In the first year, with average air temperatures, we saw little response to our...
A portable wind tunnel was used to test the contribution of biological and physical elements to overall soil aggregation on a soil dominated by biological soil crusts in south-eastern Australia. After moderate disturbance and simulated wind erosion, 90% of surface aggregates on the loamy soil and 76% on the sandy soil were dominated by biological elements (cryptogams). Lower levels of biological bonding were observed on the severely disturbed treatment. Linear regression indicated a significant positive relationship (r2=0·72) between biological soil crust cover and dry aggregation levels greater than 0·85mm. To maintain sediment transport below an erosion control target of 5gm−1s−1 for a 65kmh−1 wind at...
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This dataset describes the identification of phytoplankton to the lowest taxonomic level (typically species), as well as abundance (density) and biovolume from grab samples collected from Lake Michigan at Jackson Park at Hyde Park, Illinois and Lake Michigan at Jeorse Park at Gary, Indiana.
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Various stressors including temperature, environmental chemicals and toxins can have profound impacts on immunity to pathogens. It is believed that increased eutrophication near rivers and lakes coupled with climate change are predicted to lead to increased algal blooms. Currently, the effects of cyanobacterial toxins on disease resistance in mammals is a largely unexplored area of research. Importantly, recent studies have suggested that freshwater cyanotoxins can elicit immunomodulation through interaction with specific components of innate immunity thus potentially altering disease susceptibility parameters for fish, wildlife and human health owing to the conserved nature of the vertebrate immune system. In this...
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This child item data set provides high-resolution, nearshore, spatial water-quality data collected from Seneca Lake, New York, on July 9-10 and October 9-10, 2019. All data are reported as raw measured values. Continuous water-quality monitors were mounted to a boat at approximately 0.5-meters below the water surface and used to measure nitrate, chlorophyll fluorescence (fChl), fluorescent dissolved organic matter (fDOM), dissolved oxygen, specific conductance, phycocyanin fluorescence (fPC), turbidity, pH, and temperature.
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This dataset is a collection of hyperspectral imagery profiles of algae, many associated with Harmful Algae Blooms (HABs). Data were collected using a microscope-based hyperspectral imaging system with the cooperation of the National Institute of Standards and Technology. Samples were collected from U.S. Geological Survey (USGS) water quality sampling efforts, to include water quality parameters and algal biomass. Data are shown in basic hyperspectral imagery form, normalized to 1.
We evaluated and optimized three rapid methods for extraction of high-quality DNA from carbonate-encrusted microbial communities using modern calcifying oncolites built by cyanobacteria and diatoms in a high-calcium freshwater river. Pulverization, acid (HCl) dissolution, and chelator-mediated (EDTA) dissolution of the carbonate matrix were used and optimized to liberate microbial cells from their mineral encasing. This was followed by cell lysis and DNA extraction and isolation. HCl dissolution yielded no measurable DNA, probably due to hydrolysis, whereas pulverization and EDTA dissolution yielded averages of 3.5 and 7.8 Î&frac14;g per gram of sample, respectively, of high molecular weight DNA. These DNA isolates...
The identity of the numerically dominant N(2)-fixing bacteria in biological soil crusts of the Colorado Plateau region and two outlying areas was determined using multiple approaches, to link the environmental diversity of nifH gene sequences to cultured bacterial isolates from the regions. Of the nifH sequence-types detected in soil crusts of the Colorado Plateau, 89% (421/473) were most closely related to nifH signature sequences from cyanobacteria of the order Nostocales. N(2)-fixing cyanobacterial strains were cultured from crusts and their morphotypes, 16S rRNA gene and nifH gene sequences were characterized. The numerically dominant diazotrophs in the Colorado Plateau crusts fell within three clades of heterocystous...
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Hand-held hyperspectral spectroscopy data were collected in 2022 in Franks Tract, a flooded area located in the central Sacramento-San Joaquin Delta of California. The data were collected from a boat and co-located within pixels from the Ocean Land Color Imaging (OLCI) sensor on the Sentinel-3A and 3-B satellites. Data from 16 sites within 7 OLCI pixels were collected on three days: July 14, August 3, and November 3, 2022. Radiance measurements from the water, sky, and a reflectance plaque were collected to enable calculation of water-leaving radiance (Mobley 1999, Ruddick et al. 2019). At the location of each spectroscopy site, discrete water samples were also collected and analyzed for chlorophyll a, dissolved...
map background search result map search result map Wind erodibility of soils at Fort Irwin, California (Mojave Desert), USA, before and after trampling disturbance: implications for land management Global change and biological soil crusts: effects of ultraviolet augmentation under altered precipitation regimes and nitrogen additions Phytoplankton taxonomy, abundance, and biovolume from two urban beaches on Southern and Western Lake Michigan, 2016-2017 Nutrient loading, flushing rate, and lake morphometry data used to identify trophic states in selected watersheds of the eastern and southeastern United States Cyanobacterial toxin effects on inflammatory response of human toll-like receptors (TLRs) Phytoplankton data for samples collected at eleven large river sites throughout the United States, June through October 2018 Seneca Lake, New York spatial water-quality data, July 9-10 and October 9-10, 2019 Hyperspectral profiles of Harmful Algal Blooms (HABs) and other algae, 2022 Above-water hyperspectral field spectroscopy measurements at Franks Tract in the Sacramento-San Joaquin Delta, California Cyanobacterial toxin effects on inflammatory response of human toll-like receptors (TLRs) Above-water hyperspectral field spectroscopy measurements at Franks Tract in the Sacramento-San Joaquin Delta, California Seneca Lake, New York spatial water-quality data, July 9-10 and October 9-10, 2019 Global change and biological soil crusts: effects of ultraviolet augmentation under altered precipitation regimes and nitrogen additions Wind erodibility of soils at Fort Irwin, California (Mojave Desert), USA, before and after trampling disturbance: implications for land management Nutrient loading, flushing rate, and lake morphometry data used to identify trophic states in selected watersheds of the eastern and southeastern United States Hyperspectral profiles of Harmful Algal Blooms (HABs) and other algae, 2022 Phytoplankton data for samples collected at eleven large river sites throughout the United States, June through October 2018