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USGS1970

Experimental control of Columnaris sisease with a new Nitrofuran drug, P-7138

P-7138 is a new, broad-spectrum, vinylogous, nitrofuran chemotherapeutic that was developed specifically for treating fish diseases. Although it can be added to the diet of fish, therapeutic tissue levels can be obtained in eels (Anguilla japonica) and goldfish (Carassius auratur) by absorption of the drug directly from the water. Moreover, the drug is eliminated from the tissues within hours and shows a low level of toxicity (Shimizu and Takase 1967). The purpose of the present study was to deterime 910 the efficacy of P-7138 in controlling an experimentally induced Chrondrococcus columnaris infection, 920 the absorption and elimination rates, and 930 the degree of acute and chronic toxicity to coho salmon (Oncorhynchus kitutch).

Progressive Fish-Culturist↗

USGS1993

An evaluation of atmospheric corrections to advanced very high resolution radiometer data

A data set compiled to analyze vegetation indices is used to evaluate the effect of atmospheric correction to AVHRR measurement in the solar spectrum. Such corrections include cloud screening and "clear sky" corrections. We used the "clouds from AVHRR" (CLAVR) method for cloud detection and evaluated its performance over vegetated targets. Clear sky corrections, designed to reduce the effects of molecular scattering and absorption due to ozone, water vapor, carbon dioxide, and molecular oxygen, were applied to data values determine to be cloud free. Generally, it was found that the screening and correction of the AVHRR data did not affect the maximum NDVI compositing process adversely, while at the same time improving estimates of the land-surface radiances over a compositing period.

Pecora 12 Symposium↗

USGS1998

Results from the Mars global surveyor thermal emission spectrometer

The Thermal Emission Spectrometer spectra of low albedo surface materials suggests that a four to one mixture of pyroxene to plagioclase, together with about a 35 percent dust component provides the best fit to the spectrum. Qualitative upper limits can be placed on the concentration of carbonates (<10 percent), olivine (<10 percent), clay minerals (<20 percent), and quartz (<5 percent) in the limited regions observed. Limb observations in the northern hemisphere reveal low-lying dust hazes and detached water-ice clouds at altitudes up to 55 kilometers. At an aerocentric longitude of 224??a major dust storm developed in the Noachis Terra region. The south polar cap retreat was similar to that observed by Viking.

Science↗

USGS2012

Freshwater DOM quantity and quality from a two-component model of UV absorbance

We present a model that considers UV-absorbing dissolved organic matter (DOM) to consist of two components (A and B), each with a distinct and constant spectrum. Component A absorbs UV light strongly, and is therefore presumed to possess aromatic chromophores and hydrophobic character, whereas B absorbs weakly and can be assumed hydrophilic. We parameterised the model with dissolved organic carbon concentrations [DOC] and corresponding UV spectra for c. 1700 filtered surface water samples from North America and the United Kingdom, by optimising extinction coefficients for A and B, together with a small constant concentration of non-absorbing DOM (0.80 mg DOC L -1 ). Good unbiased predictions of [DOC] from absorbance data at 270 and 350 nm were obtained ( r 2 = 0.98), the sum of squared residuals in [DOC] being reduced by 66% compared to a regression model fitted to absorbance at 270 nm alone. The parameterised model can use measured optical absorbance values at any pair of suitable wavelengths to calculate both [DOC] and the relative amounts of A and B in a water sample, i.e. measures of quantity and quality. Blind prediction of [DOC] was satisfactory for 9 of 11 independent data sets (181 of 213 individual samples).

Water Research↗

USGS1996

Integration of orthophotographic and sidescan sonar imagery: an example from Lake Garda, Italy

Digital orthophotos of Lake Garda basin area are available at the scale of up to 1:10,000 from a 1994 high altitude (average scale of 1:75,000) air photo coverage of Italy collected with an RC30 camera and Panatomic film. In October 1994 the lake bed was surveyed by USGS and CISIG personnel using a SIS 1000 Sea-Floor Mapping System. Subsystems of the SIS-1000 include high resolution sidescan sonar and sub-bottom profiler. The sidescan imagery was collected in ranges up to 1500m, while preserving a 50cm pixel resolution. The system was navigated using differential GPS. The extended operational range of the sidescan sonar permitted surveying the 370km lake area in 11 days. Data were compiled into a digital image with a pixel resolution of about 2m and stored as 12 gigabytes in exabyte 8mm tape and converted from WGS84 coordinate system to the European Datum (ED50) and integrated with bathymetric data digitized from maps.The digital bathymetric model was generated by interpolation using commercial software and was merged with the land elevation model to obtain a digital elevation model of the Lake Garda basin.The sidescan image data was also projected in the same coordinate system and seamed with the digital orthophoto of the land to produce a continuous image of the basin as if the water were removed. Some perspective scenes were generated by combining elevation and bathymetric data with basin and lake floor images. In deep water the lake's thermal structure created problems with the imagery indicating that winter or spring is best survey period. In shallow waters, ≤ 10 m, where data are missing, the bottom data gap can be filled with available images from the first few channels of the Daedalus built MIVIS, a 102 channel hyperspectral scanner with 20 channel bands of 0.020 μm width, operating in the visible part of the spectrum. By integrating orthophotos with sidescan imagery we can see how the basin morphology extends across the lake, the paths taken by the lake inlet along the lake bed and the areal distribution of sediments. An extensive exposure of debris aprons were noted on the western side of the lake. Various anthropogenic objects were recognized: pipelines, sites of waste disposal on the lake's bed, and relicts of Venitian and Austrian(?) boats.

Lake Garda↗

USGS2015

Dynamic triggering

Dynamic stresses propagating as seismic waves from large earthquakes trigger a spectrum of responses at global distances. In addition to locally triggered earthquakes in a variety of tectonic environments, dynamic stresses trigger tectonic (nonvolcanic) tremor in the brittle–plastic transition zone along major plate-boundary faults, activity changes in hydrothermal and volcanic systems, and, in hydrologic domains, changes in spring discharge, water well levels, soil liquefaction, and the eruption of mud volcanoes. Surface waves with periods of 15–200 s are the most effective triggering agents; body-wave trigger is less frequent. Triggering dynamic stresses can be < 1 kPa.

Book chapter↗

USGS2012

State of the art satellite and airborne marine oil spill remote sensing: Application to the BP Deepwater Horizon oil spill

The vast and persistent Deepwater Horizon (DWH) spill challenged response capabilities, which required accurate, quantitative oil assessment at synoptic and operational scales. Although experienced observers are a spill response's mainstay, few trained observers and confounding factors including weather, oil emulsification, and scene illumination geometry present challenges. DWH spill and impact monitoring was aided by extensive airborne and spaceborne passive and active remote sensing. Oil slick thickness and oil-to-water emulsion ratios are key spill response parameters for containment/cleanup and were derived quantitatively for thick (> 0.1 mm) slicks from AVIRIS (Airborne Visible/Infrared Imaging Spectrometer) data using a spectral library approach based on the shape and depth of near infrared spectral absorption features. MODIS (Moderate Resolution Imaging Spectroradiometer) satellite, visible-spectrum broadband data of surface-slick modulation of sunglint reflection allowed extrapolation to the total slick. A multispectral expert system used a neural network approach to provide Rapid Response thickness class maps. Airborne and satellite synthetic aperture radar (SAR) provides synoptic data under all-sky conditions; however, SAR generally cannot discriminate thick (> 100 μm) oil slicks from thin sheens (to 0.1 μm). The UAVSAR's (Uninhabited Aerial Vehicle SAR) significantly greater signal-to-noise ratio and finer spatial resolution allowed successful pattern discrimination related to a combination of oil slick thickness, fractional surface coverage, and emulsification. In situ burning and smoke plumes were studied with AVIRIS and corroborated spaceborne CALIPSO (Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observation) observations of combustion aerosols. CALIPSO and bathymetry lidar data documented shallow subsurface oil, although ancillary data were required for confirmation. Airborne hyperspectral, thermal infrared data have nighttime and overcast collection advantages and were collected as well as MODIS thermal data. However, interpretation challenges and a lack of Rapid Response Products prevented significant use. Rapid Response Products were key to response utilization—data needs are time critical; thus, a high technological readiness level is critical to operational use of remote sensing products. DWH's experience demonstrated that development and operationalization of new spill response remote sensing tools must precede the next major oil spill.

Remote Sensing of Environment↗

USGS1998

Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory-Determination of 86 volatile organic compounds in water by gas chromatography/mass spectrometry, including detections less than reporting limits

This report presents precision and accuracy data for volatile organic compounds (VOCs) in the nanogram-per-liter range, including aromatic hydrocarbons, reformulated fuel components, and halogenated hydrocarbons using purge and trap capillary-column gas chromatography/mass spectrometry. One-hundred-four VOCs were initially tested. Of these, 86 are suitable for determination by this method. Selected data are provided for the 18 VOCs that were not included. This method also allows for the reporting of semiquantitative results for tentatively identified VOCs not included in the list of method compounds. Method detection limits, method performance data, preservation study results, and blank results are presented. The authors describe a procedure for reporting low-concentration detections at less than the reporting limit. The nondetection value (NDV) is introduced as a statistically defined reporting limit designed to limit false positives and false negatives to less than 1 percent. Nondetections of method compounds are reported as ?less than NDV.? Positive detections measured at less than NDV are reported as estimated concentrations to alert the data user to decreased confidence in accurate quantitation. Instructions are provided for analysts to report data at less than the reporting limits. This method can support the use of either method reporting limits that censor detections at lower concentrations or the use of NDVs as reporting limits. The data-reporting strategy for providing analytical results at less than the reporting limit is a result of the increased need to identify the presence or absence of environmental contaminants in water samples at increasingly lower concentrations. Long-term method detection limits (LTMDLs) for 86 selected compounds range from 0.013 to 2.452 micrograms per liter (?g/L) and differ from standard method detection limits (MDLs) in that the LTMDLs include the long-term variance of multiple instruments, multiple operators, and multiple calibrations over a longer time. For these reasons, LTMDLs are expected to be slightly higher than standard MDLs. Recoveries for all of the VOCs tested ranged from 36 (tert-butyl formate) to 155 percent (pentachlorobenzene). The majority of the compounds ranged from 85 to 115 percent recovery and had less than 5 percent relative standard deviation for concentrations spiked between 1 to 500 ?g/L in volatile blank-, surface-, and ground-water samples. Recoveries of 60 set spikes at low concentrations ranged from 70 to 114 percent (1,2,3- trimethylbenzene and acetone). Recovery data were collected over 6 months with multiple instruments, operators, and calibrations. In this method, volatile organic compounds are extracted from a water sample by actively purging with helium. The VOCs are collected onto a sorbent trap, thermally desorbed, separated by a Megabore gas chromatographic capillary column, and finally determined by a full-scan quadrupole mass spectrometer. Compound identification is confirmed by the gas chromatographic retention time and by the resultant mass spectrum, typically identified by three unique ions. An unknown compound detected in a sample can be tentatively identified by comparing the unknown mass spectrum to reference spectra in the mass-spectra computer-data system library compiled by the National Institute of Standards and Technology.

Open-File Report↗

USGS1984

Inter-pulse high-resolution gamma-ray spectra using a 14 MeV pulsed neutron generator

A neutron generator pulsed at 100 s-1 was suspended in an artificial borehole containing a 7.7 metric ton mixture of sand, aragonite, magnetite, sulfur, and salt. Two Ge(HP) gamma-ray detectors were used: one in a borehole sonde, and one at the outside wall of the sample tank opposite the neutron generator target. Gamma-ray spectra were collected by the outside detector during each of 10 discrete time windows during the 10 ms period following the onset of gamma-ray build-up after each neutron burst. The sample was measured first when dry and then when saturated with water. In the dry sample, gamma rays due to inelastic neutron scattering, neutron capture, and decay were counted during the first (150 ??s) time window. Subsequently only capture and decay gamma rays were observed. In the wet sample, only neutron capture and decay gamma rays were observed. Neutron capture gamma rays dominated the spectrum during the period from 150 to 400 ??s after the neutron burst in both samples, but decreased with time much more rapidly in the wet sample. A signal-to-noise-ratio (S/N) analysis indicates that optimum conditions for neutron capture analysis occurred in the 350-800 ??s window. A poor S/N in the first 100-150 ??s is due to a large background continuum during the first time interval. Time gating can be used to enhance gamma-ray spectra, depending on the nuclides in the target material and the reactions needed to produce them, and should improve the sensitivity of in situ well logging. ?? 1984.

Nuclear Instruments and Methods In Physics Researc↗

USGS2006

Monitoring super-volcanoes: Geophysical and geochemical signals at Yellowstone and other large caldera systems

Earth's largest calderas form as the ground collapses during immense volcanic eruptions, when hundreds to thousands of cubic kilometres of magma are explosively withdrawn from the Earth's crust over a period of days to weeks. Continuing long after such great eruptions, the resulting calderas often exhibit pronounced unrest, with frequent earthquakes, alternating uplift and subsidence of the ground, and considerable heat and mass flux. Because many active and extinct calderas show evidence for repetition of large eruptions, such systems demand detailed scientific study and monitoring. Two calderas in North America, Yellowstone (Wyoming) and Long Valley (California), are in areas of youthful tectonic complexity. Scientists strive to understand the signals generated when tectonic, volcanic and hydrothermal (hot ground water) processes intersect. One obstacle to accurate forecasting of large volcanic events is humanity's lack of familiarity with the signals leading up to the largest class of volcanic eruptions. Accordingly, it may be difficult to recognize the difference between smaller and larger eruptions. To prepare ourselves and society, scientists must scrutinize a spectrum of volcanic signals and assess the many factors contributing to unrest and toward diverse modes of eruption. ?? 2006 The Royal Society.

Philosophical Transactions of the Royal Society A:↗

USGS2015

Studies by the U.S. Geological Survey in Alaska, Volume 15

Summary Professional Paper 1814— Studies by the U.S. Geological Survey in Alaska, Volume 15 —continues a long-running series of collected volumes of U.S. Geological Survey (USGS) scientific reports on Alaska. This series presents new and sometimes preliminary findings that are of interest to Earth and biological scientists in academia, government, and industry; to land and resource managers; and to the general public. The series covers a broad spectrum of scientific topics, from various parts of Alaska, serving to emphasize the diversity of USGS efforts to meet the Nation’s needs for Earth-science information in the State. The USGS provides reliable scientific information to describe and understand the Earth; minimize loss of life and property from natural disasters; manage water, biological, energy, and mineral resources; and enhance and protect our quality of life.

Professional Paper↗

USGS2007

Earth science and public health: Proceedings of the Second National Conference on USGS Health-Related Research

The mission of the U.S. Geological Survey (USGS) is to serve the Nation by providing reliable scientific information to describe and understand the earth; minimize loss of life and property from natural disasters; manage water, biological, energy, and mineral resources; and enhance and protect our quality of life. As the Nation?s largest water, earth, and biological science and civilian mapping agency, the USGS can play a significant role in providing scientific knowledge and information that will improve our understanding of the relations of environment and wildlife to human health and disease. USGS human health-related research is unique in the Federal government because it brings together a broad spectrum of natural science expertise and information, including extensive data collection and monitoring on varied landscapes and ecosystems across the Nation. USGS can provide a great service to the public health community by synthesizing the scientific information and knowledge on our natural and living resources that influence human health, and by bringing this science to the public health community in a manner that is most useful. Partnerships with health scientists and managers are essential to the success of these efforts. USGS scientists already are working closely with the public health community to pursue rigorous inquiries into the connections between natural science and public health. Partnering agencies include the Armed Forces Institute of Pathology, Agency for Toxic Substances Disease Registry, Centers for Disease Control and Prevention, U.S. Environmental Protection Agency, Food and Drug Administration, Mine Safety and Health Administration, National Cancer Institute, National Institute of Allergy and Infectious Disease, National Institute of Environmental Health Sciences, National Institute for Occupational Safety and Health, U.S. Public Health Service, and the U.S. Army Medical Research Institute of Infectious Diseases. Collaborations between public health scientists and earth scientists can lead to improved solutions for existing and emerging environmental health problems. This report summarizes the presentations and discussions held at the Second National Conference on USGS Health-Related Research, held at the USGS national headquarters in Reston, Virginia. The report presents 68 abstracts of technical presentations made at the conference and summaries of six topical breakout sessions. The abstracts cover a broad range of issues and demonstrate connections between human health and the quality and condition of our environment and wildlife. The summaries of the topical breakout sessions present ideas for advancing interdisciplinary science in areas of earth science and human health.

Scientific Investigations Report↗

USGS2012

Groundwater quality in the Columbia Plateau, Snake River Plain, and Oahu basaltic-rock and basin-fill aquifers in the Northwestern United States and Hawaii, 1992-2010

This assessment of groundwater-quality conditions of the Columbia Plateau, Snake River Plain, and Oahu for the period 1992–2010 is part of the U.S. Geological Survey’s National Water Quality Assessment (NAWQA) program. It shows where, when, why, and how specific water-quality conditions occur in groundwater of the three study areas and yields science-based implications for assessing and managing the quality of these water resources. The primary aquifers in the Columbia Plateau, Snake River Plain, and Oahu are mostly composed of fractured basalt, which makes their hydrology and geochemistry similar. In spite of the hydrogeologic similarities, there are climatic differences that affect the agricultural practices overlying the aquifers, which in turn affect the groundwater quality. Understanding groundwater-quality conditions and the natural and human factors that control groundwater quality is important because of the implications to human health, the sustainability of rural agricultural economies, and the substantial costs associated with land and water management, conservation, and regulation. The principal regional aquifers of the Columbia Plateau, Snake River Plain, and Oahu are highly vulnerable to contamination by chemicals applied at the land surface; essentially, they are as vulnerable as many shallow surficial aquifers elsewhere. The permeable and largely unconfined character of principal aquifers in the Columbia Plateau, Snake River Plain, and Oahu allow water and chemicals to infiltrate to the water table despite depths to water commonly in the hundreds of feet. The aquifers are essentially unconfined over large areas, having few extensive clay layers to impede infiltration through permeable volcanic rock and alluvial sediments. Agriculture is intensive in all three study areas, and heavy irrigation has imposed large artificial flows of irrigation recharge that rival or exceed natural recharge rates. Fertilizers and pesticides applied at land surface are leached from soil and transported to deep water tables with the infiltrating irrigation recharge, resulting in a layer of degraded water quality overlying better quality regional groundwater beneath. This “irrigation-recharge layer” is best known on Oahu, where it has been studied since the 1960s; however, the extent of nitrate and pesticide contamination in the Columbia Plateau and Snake River Plain indicate that the same situation exists in those areas. Contamination from agricultural and urban activities is present not only at shallow depths in surficial materials of the three areas, but extends regionally in the deep, principal bedrock aquifers that are tapped for drinking water by domestic and public-supply wells. Naturally occurring constituents and nitrate concentrations above human-health benchmarks—Maximum Contaminant Levels (MCLs), and Health-Based Screening Levels (HBSLs)—were more common in the Columbia Plateau and the Snake River Plain than in Oahu. Concentrations of anthropogenic constituents (constituents related to human activities) above human-health benchmarks were more common in Oahu. Naturally occurring contaminants, such as arsenic and radon, may be present in groundwater at concentrations of potential concern for human health in relatively undeveloped settings that otherwise may not be perceived as susceptible to contamination. Even though the median depth to groundwater in Oahu is more than 300 feet, the common occurrence of anthropogenic compounds in groundwater indicates that Oahu has a high susceptibility to contamination. Nitrate concentrations in groundwater were above the national background concentrations of 1 milligram per liter (mg/L) in all three study areas. In the Columbia Plateau, nitrate exceeded the human-health benchmark of 10 mg/L in 20 percent of the wells sampled. In the Snake River Plain, nitrate exceeded the human-health benchmark of 10 mg/L in 3 percent of the wells sampled. Nitrate can persist in groundwater for years and even decades in the oxygen-rich groundwater of the Columbia Plateau and the Snake River Plain, so prudent groundwater protection measures are critical to protect drinking water resources by reducing nitrate leaching from the land surface. Nitrate logistic regression models indicated that areas with a high percentage of land in crops (such as potatoes or sugarcane) and soils with low amounts of organic matter are most likely to have elevated nitrate concentrations in the groundwater. Areas where agricultural activities were absent had much lower probabilities of detecting elevated nitrate concentrations. The Columbia Plateau had a much higher probability of having elevated nitrate concentrations, with most of the land area having greater than a 50 percent probability of elevated nitrate concentrations. Oahu and the Snake River Plain had a much lower probability of having elevated nitrate concentrations because of their lower percentage of agricultural land. Pesticides were detected at many sites in groundwater of the Columbia Plateau, Snake River Plain, and Oahu but generally at low concentrations below human-health benchmarks. Atrazine and its degradate (a compound produced from the breakdown of a parent pesticide), deethylatrazine, were the most commonly detected pesticides in groundwater sampled in the Columbia Plateau and Snake River Plain. Bromacil was the most commonly detected pesticide on Oahu. The other pesticides most commonly detected in the study areas include simazine, hexazinone, metribuzin, diuron, prometon, metolachlor, p,p’ -DDE, dieldrin, 2-4-D, and alachlor. DDE (a degradate of DDT) and dieldrin are still being detected in groundwater despite having been banned for more than 30 years. Codetection of multiple pesticides in water from a single well was common. The widespread occurrence of pesticides in groundwater in the study areas indicates that the groundwater is highly susceptible to pesticide contamination. Some pesticides were detected in groundwater samples from all three study areas, but other pesticides were detected only in samples from Oahu, or only in samples from the Columbia Plateau and Snake River Plain. This is because some pesticides (such as atrazine) are broad-spectrum pesticides that are used on many crops in many different areas of the United States. Other pesticides (such as simazine, metribuzin, and metolachlor) are used on row crops (such as potatoes, barley, and alfalfa) grown in the Columbia Plateau and Snake River Plain, but not on pineapple or sugarcane grown in Oahu. Atrazine logistic-regression models indicate that areas with a high percentage of land in crops (such as potatoes or sugarcane), a low percentage of fallow land, and highly permeable soils with low amounts of organic matter are most likely to have atrazine detected in the groundwater. Areas where agricultural activities were absent had much lower probabilities of atrazine being detected. The Snake River Plain had a much higher probability of atrazine detections, with more than 50 percent of the land area having greater than a 50 percent probability of atrazine contamination. Oahu had a much lower probability of atrazine contamination, with only 24 percent of the land area having greater than a 50 percent probability of atrazine contamination. Oahu and the Columbia Plateau had some of the highest percentages of soil fumigant detections in groundwater in the United States. Soil fumigants are volatile organic compounds (VOCs) used as pesticides, which are applied to soils to reduce populations of plant parasitic nematodes (harmful rootworms), weeds, fungal pathogens, and other soil-borne microorganisms. They are used in Oahu and the Columbia Plateau on crops such as pineapple and potatoes. All three areas (Columbia Plateau, Snake River Plain, and Oahu) had fumigant concentrations exceeding human-health benchmarks for drinking water.

Hawai'i, Idaho, Nevada, Oregon, Utah, Washington, ↗

USGS2011

Diel biogeochemical processes and their effect on the aqueous chemistry of streams: A review

This review summarizes biogeochemical processes that operate on diel, or 24-h, time scales in streams and the changes in aqueous chemistry that are associated with these processes. Some biogeochemical processes, such as those producing diel cycles of dissolved O 2 and pH, were the first to be studied, whereas processes producing diel concentration cycles of a broader spectrum of chemical species including dissolved gases, dissolved inorganic and organic carbon, trace elements, nutrients, stable isotopes, and suspended particles have received attention only more recently. Diel biogeochemical cycles are interrelated because the cyclical variations produced by one biogeochemical process commonly affect another. Thus, understanding biogeochemical cycling is essential not only for guiding collection and interpretation of water-quality data but also for geochemical and ecological studies of streams. Expanded knowledge of diel biogeochemical cycling will improve understanding of how natural aquatic environments function and thus lead to better predictions of how stream ecosystems might react to changing conditions of contaminant loading, eutrophication, climate change, drought, industrialization, development, and other factors.

Chemical Geology↗

USGS2019

Microbial assemblages reflect environmental heterogeneity in alpine streams

Alpine streams are dynamic habitats harboring substantial biodiversity across small spatial extents. The diversity of alpine stream biota is largely reflective of environmental heterogeneity stemming from varying hydrological sources. Globally, alpine stream diversity is under threat as meltwater sources recede and stream conditions become increasingly homogeneous. Much attention has been devoted to macroinvertebrate diversity in alpine headwaters, yet to fully understand the breadth of climate change threats, a more thorough accounting of microbial diversity is needed. We characterized microbial diversity (specifically Bacteria and Archaea) of 13 streams in two disjunct Rocky Mountain subranges through 16S rRNA gene sequencing. Our study encompassed the spectrum of alpine stream sources (glaciers, snowfields, subterranean ice, and groundwater) and three microhabitats (ice, biofilms, and streamwater). We observed no difference in regional (γ) diversity between subranges but substantial differences in diversity among (β) stream types and microhabitats. Within‐stream (α) diversity was highest in groundwater‐fed springs, lowest in glacier‐fed streams, and positively correlated with water temperature for both streamwater and biofilm assemblages. We identified an underappreciated alpine stream type—the icy seep—that are fed by subterranean ice, exhibit cold temperatures (summer mean <2°C), moderate bed stability, and relatively high conductivity. Icy seeps will likely be important for combatting biodiversity losses as they contain similar microbial assemblages to streams fed by surface ice yet may be buffered against climate change by insulating debris cover. Our results show that the patterns of microbial diversity support an ominous trend for alpine stream biodiversity; as meltwater sources decline, stream communities will become more diverse locally, but regional diversity will be lost. Icy seeps, however, represent a source of optimism for the future of biodiversity in these imperiled ecosystems.

Montana↗

USGS1990

The quantification of instream flow rights to water

Energy development of all types continues to grow in the Rocky Mountain Region of the western United States. Federal resource managers increasingly need to balance energy demands, their effects on the natural and human landscape, and public perceptions towards these issues. The Western Energy Citation Clearinghouse (WECC v.1.0), part of a suite of data and information management tools developed and managed by the Wyoming Landscape Conservation Initiative (WLCI), provides resource managers with a searchable online database of citations that covers a broad spectrum of energy and landscape related topics relevant to resource managers, such as energy sources, natural and human landscape effects, and new research, methods and models. Based on the 2011 USGS Open-file Report "Abbreviated bibliography on energy development" (Montag, et al. 2011), WECC is an extensive collection of energy-related citations, as well as categorized lists of additional online resources related to oil and gas development, best practices, energy companies and Federal agencies. WECC incorporates the powerful web services of Sciencebase 2.0, the enterprise data and information platform for USGS scientists and partners, to provide secure, role-based data management features. For example, public/unauthenticated WECC users have full search and read access to the entire energy citation collection, while authenticated WLCI data stewards can manage WECC's citation collection using Sciencebase data management forms.

Book↗

USGS2018

A surrogate regression approach for computing continuous loads for the tributary nutrient and sediment monitoring program on the Great Lakes

Water quality (WQ) in many Great Lake tributaries has been degraded (increased nutrient and sediment concentrations) due to changes in their watersheds, resulting in downstream eutrophication. As part of the Great Lakes Water Quality Agreement, specific goals were established for loading of specific constituents (e.g., phosphorus). In 2010, the Great Lakes Restoration Initiative was launched to identify problem areas, accelerate restoration efforts, and track their progress. In 2011, the U.S. Geological Survey established a monitoring program on 30 tributaries to the lakes, representing ~ 46% of the U.S. draining area and the spectrum of land uses. Discrete measurements of nutrients and suspended sediment, and continuous measurements of flow and WQ surrogates (turbidity, temperature, specific conductance, pH, and dissolved oxygen) are being collected in these tributaries to document their WQ and estimate continuous (5-min) loading. To estimate loadings, two regression models were developed for each constituent for each site: one using continuous flow and a seasonality factor; and one using flow, seasonality, and continuous surrogates. Variables included in the final models for each constituent were chosen from the explanatory variables that worked “best” for all sites. In computing loads, when continuous surrogate data were unavailable for short periods, loads were computed using the flow and seasonality models. Prediction intervals for all loads were calculated using results from both models. These results provide a better understanding of short-term variability and long-term changes in loading affecting the environmental health of the Great Lakes than traditional regression techniques that employ only flow and seasonality parameters.

Great Lake↗

USGS2005

Remote sensing for environmental site screening and watershed evaluation in Utah Mine lands: East Tintic mountains, Oquirrh mountains, and Tushar mountains

Imaging spectroscopy-a powerful remote-sensing tool for mapping subtle variations in the composition of minerals, vegetation, and man-made materials on the Earth's surface-was applied in support of environmental assessments and watershed evaluations in several mining districts in the State of Utah. Three areas were studied through the use of Landsat 7 ETM+ and Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data: (1) the Tintic mining district in the East Tintic Mountains southwest of Provo, (2) the Camp Floyd mining district (including the Mercur mine) and the Stockton (or Rush Valley) mining district in the Oquirrh Mountains south of the Great Salt Lake, and (3) the Tushar Mountains and Antelope Range near Marysvale. The Landsat 7 ETM+ data were used for initial site screening and the planning of AVIRIS surveys. The AVIRIS data were analyzed to create spectrally defined maps of surface minerals with special emphasis on locating and characterizing rocks and soils with acid-producing potential (APP) and acid-neutralizing potential (ANP). These maps were used by the United States Environmental Protection Agency (USEPA) for three primary purposes: (1) to identify unmined and anthropogenic sources of acid generation in the form of iron sulfide and (or) ferric iron sulfate-bearing minerals such as jarosite and copiapite; (2) to seek evidence for downstream or downwind movement of minerals associated with acid generation, mine waste, and (or) tailings from mines, mill sites, and zones of unmined hydrothermally altered rocks; and (3) to identify carbonate and other acid-buffering minerals that neutralize acidic, potentially metal bearing, solutions and thus mitigate potential environmental effects of acid generation. Calibrated AVIRIS surface-reflectance data were spectrally analyzed to identify and map selected surface materials. Two maps were produced from each flightline of AVIRIS data: a map of iron-bearing minerals and water having absorption features in the spectral region from 0.35 µ m to 1.35 µ m and a map of minerals (including clays, sulfates, micas, and carbonates) having absorptions in the spectral region from 1.45 µ m to 2.51 µ m. Several methods were used to verify the AVIRIS mapping results, including field checking of selected locations with a portable spectrometer, visual inspection of the AVIRIS reflectance spectra, and X-ray diffraction (XRD) analysis of field samples. The maps of iron-bearing minerals derived from analysis of the visible (VIS) and near-infrared (NIR) regions of the electromagnetic spectrum were shown to be more consistently reliable in indicating the presence of jarosite than were the maps generated from analysis of the short-wave infrared (SWIR) region. When present in abundance, phyllosilicate minerals tend to dominate the SWIR and mask the spectral features of jarosite in that wavelength region. The crystal field absorptions of jarosite in the VIS and NIR spectral regions will commonly be present regardless of whether the Fe-OH absorption feature near 2.27 µ m can be detected. For this reason, the VIS and NIR were preferable to the SWIR for the remote spectroscopic identification of jarosite (and other iron-bearing minerals). Large exposures of unmined hydrothermally altered rocks occur throughout the three study areas. These rocks commonly contain sulfide or sulfate minerals that produce sulfuric acid upon subaerial oxidation. The acid may be introduced into local surface and ground water and thus lower the baseline (that is, the premining) pH for a watershed.

Utah↗