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At least 1,009 records · Page 56Linked to original sources
USGS2023

Genetic analysis of North American Phragmites australis guides management approaches

Phragmites australis subsp. australis is an invasive and ecologically detrimental plant in multiple regions of North America. Its co-occurrence with the native subspecies, and multiple instances of hybridization, has created the need to differentiate Phragmites subspecies or haplotypes so that management can be appropriately targeted to the invader. We compiled a review of current genetic discrimination methods among the three Phragmites subspecies inhabiting the United States and Canada, and discussed how each method can contribute to control of the introduced subspecies while preserving the two endemic subspecies. We also discussed various control tools and the implications of Phragmites genetics for implementation. The Phragmites subspecies endemic to North America have environmental or infrastructure significance (e.g., habitat sustainability, biodiversity, storm surge and erosion protection). Thus, faster and more accurate differentiation among the endemic and introduced subspecies is needed. Additionally, more in-depth genetic information on Phragmites subspecies could support better management decisions, as well as the development of improved control treatments. This review highlights technologies and approaches currently available for genetic identification, recently collected genomic, transcriptomic and proteomic information, and implications for biological control and herbicide treatments.

Aquatic Botany↗
USGS2005

Screening and evaluation of polymers as flocculation aids for the treatment of aquacultural effluents

As environmental regulations become more stringent, environmentally sound waste management and disposal are becoming increasingly more important in all aquaculture operations. One of the primary water quality parameters of concern is the suspended solids concentration in the discharged effluent. For example, EPA initially considered the establishment of numerical limitations for only one single pollutant: total suspended solids (TSS). For recirculation systems, the proposed TSS limitations would have applied to solids polishing or secondary solids removal technology. The new rules and regulations from EPA (August 23, 2004) require only qualitative TSS limits, in the form of solids control best management practices (BMP), allowing individual regional and site specific conditions to be addressed by existing state or regional programs through NPDES permits. In recirculation systems, microscreen filters are commonly used to remove the suspended solids from the process water. Further concentration of suspended solids from the backwash water of the microscreen filter could significantly reduce quantity of discharge water. And in some cases, the backwash water from microscreen filters needs to be further concentrated to minimize storage volume during over wintering for land disposal or other final disposal options. In addition, this may be required to meet local, state, and regional discharge water quality. The objective of this research was an initial screening of several commercially available polymers routinely used as coagulation-flocculation aids in the drinking and wastewater treatment industry and determination of their effectiveness for the treatment of aquaculture wastewater. Based on the results of the initial screening, a further evaluation of six polymers was conducted to estimate the optimum polymer dosage for flocculation of aquaculture microscreen effluent and overall solids removal efficiency. Results of these evaluations show TSS removal was close to 99% via settling, with final TSS values ranging from as low as 10-17 mg/L. Although not intended to be used for reactive phosphorus (RP) removal, RP was reduced by 92-95% by removing most of the TSS in the wastewater to approximately 1 mg/L-P. Dosage requirements were fairly uniform, requiring between 15 and 20 mg/L of polymer. Using these dosages, estimated costs range from $4.38 to $13.08 per metric tonne of feed. ?? 2005 Elsevier B.V. All rights reserved.

Aquacultural Engineering↗
USGS2007

Use of avoidance response by rainbow trout to carbon dioxide for fish self-transfer between tanks

Convenient, economical, and reduced labor fish harvest and transfer systems are required to realize operating cost savings that can be achieved with the use of much larger and deeper circular culture tanks. To achieve these goals, we developed a new technology for transferring fish based on their avoidance behavior to elevated concentrations of dissolved carbon dioxide (CO2). We observed this behavioral response during controlled, replicated experiments that showed dissolved CO2 concentrations of 60-120 mg/L induced rainbow trout (Oncorhynchus mykiss) to swim out of their 11 m3 "growout" tank, through a transfer pipe carrying a flow with ???23 mg/L dissolved CO2, into a second 11 m3 "harvest" tank. The research was conducted using separate groups of rainbow trout held at commercially relevant densities (40-60 kg/m3). The average weight of fish ranged from 0.15 to 1.3 kg during the various trials. In all trials that used a constant flow of low CO2 water (???23 mg/L) entering the growout tank from the harvest tank, approximately 80-90% of the fish swam from the growout tank, through the transfer pipe, and into the harvest tank after the CO2 concentration in the growout tank had exceeded 60 mg/L. The fish that remained in the growout tank stayed within the area of relatively low CO2 water at the entrance of the transfer pipe. However, the rate of fish transfer from the growout tank to the harvest tank was more than doubled when the diameter of the transfer pipe was increased from 203 to 406 mm. To consistently achieve fish transfer efficiencies of 99%, water flow rate through the fish transfer pipe had to be reduced to 10-20% of the original flow just before the conclusion of each trial. Reducing the flow of relatively low CO2 water near the end of each fish transfer event, restricted the zone of relatively low CO2 water about the entrance of the fish transfer pipe, and provided the stimulus for all but a few remaining fish to swim out of the growout tank. Results indicate that the CO2 avoidance technique can provide a convenient, efficient, more economical, and reduced labor approach for fish transfer, especially in applications using large and well mixed circular culture tanks. ?? 2007 Elsevier B.V. All rights reserved.

Aquacultural Engineering↗
USGS2005

Atmospheric dry deposition in the vicinity of the Salton Sea, California - II: Measurement and effects of an enhanced evaporation system

A study was conducted to determine the effects of salt spray drift from pilot technologies employed by the US Bureau of Reclamation on deposition rates of various air-born ions. An enhanced evaporation system (EES) was tested in the field at the Salton Sea, California. Dry deposition of NO3-, NH4+, SO42-, Cl-, Ca2+, Na+, K+ and Se was assessed by using nylon filters and branches of natural vegetation exposed for one-week long periods. The simultaneous exposure of both lyophilized branches and branches of live plants offered important information highlighting the dynamics of deposited ions on vegetation. The EES significantly increased the deposition rates of Cl-, SO42- and Na+ in an area of about 639-1062 m surrounding the sprayers. Similarly, higher deposition of Ca 2+ and K+ caused by the EES was detected only when deposition was assessed using nylon filters or lyophilized branches. Deposition fluxes of NO3-, NH4+ and Se were not affected by the spraying system. Techniques for measuring dry deposition and calculating landscape-level depositional loads in non-forested systems need further development. ?? 2005 Elsevier Ltd. All rights reserved.

Atmospheric Environment↗
USGS2012

A collaborative approach for estimating terrestrial wildlife abundance

Accurately estimating abundance of wildlife is critical for establishing effective conservation and management strategies. Aerial methodologies for estimating abundance are common in developed countries, but they are often impractical for remote areas of developing countries where many of the world's endangered and threatened fauna exist. The alternative terrestrial methodologies can be constrained by limitations on access, technology, and human resources, and have rarely been comprehensively conducted for large terrestrial mammals at landscape scales. We attempted to overcome these problems by incorporating local peoples into a simultaneous point count of Asiatic wild ass (Equus hemionus) and goitered gazelle (Gazella subgutturosa) across the Great Gobi B Strictly Protected Area, Mongolia. Paired observers collected abundance and covariate metrics at 50 observation points and we estimated population sizes using distance sampling theory, but also assessed individual observer error to examine potential bias introduced by the large number of minimally trained observers. We estimated 5671 (95% CI = 3611–8907) wild asses and 5909 (95% CI = 3762–9279) gazelle inhabited the 11,027 km 2 study area at the time of our survey and found that the methodology developed was robust at absorbing the logistical challenges and wide range of observer abilities. This initiative serves as a functional model for estimating terrestrial wildlife abundance while integrating local people into scientific and conservation projects. This, in turn, creates vested interest in conservation by the people who are most influential in, and most affected by, the outcomes.

Biological Conservation↗
USGS2015

Avoidance of unconventional oil wells and roads exacerbates habitat loss for grassland birds in the North American great plains

Oil development in the Bakken shale region has increased rapidly as a result of new technologies and strong demand for fossil fuel. This region also supports a particularly high density and diversity of grassland bird species, which are declining across North America. We examined grassland bird response to unconventional oil extraction sites (i.e. developed with hydraulic fracturing and horizontal drilling techniques) and associated roads in North Dakota. Our goal was to quantify the amount of habitat that was indirectly degraded by oil development, as evidenced by patterns of avoidance by birds. Grassland birds avoided areas within 150 m of roads (95% CI: 87–214 m), 267 m of single-bore well pads (95% CI: 157–378 m), and 150 m of multi-bore well pads (95% CI: 67–233 m). Individual species demonstrated variable tolerance of well pads. Clay-colored sparrows ( Spizella pallida ) were tolerant of oil-related infrastructure, whereas Sprague's pipit ( Anthus spragueii ) avoided areas within 350 m (95% CI: 215–485 m) of single-bore well pads. Given these density patterns around oil wells, the potential footprint of any individual oil well, and oil development across the region, is greatly multiplied for sensitive species. Efforts to reduce new road construction, concentrate wells along developed corridors, combine numerous wells on multi-bore pads rather than build many single-bore wells, and to place well pads near existing roads will serve to minimize loss of suitable habitat for birds. Quantifying environmental degradation caused by oil development is a critical step in understanding how to better mitigate harm to wildlife populations.

Biological Conservation↗
USGS2015

A reply to Iversen et al.'s comment “Monitoring of animal abundance by environmental DNA - An increasingly obscure perspective”

We appreciate the conversation put forward by Iversen et al. (2015) in their response to our article “Quantification of eDNA shedding rates from invasive bighead carp Hypophthalmichthys nobilis and silver carp Hypophthalmichthys molitrix ” in the 2015 environmental DNA special issue of Biological Conservation. We agree with Iversen et al.'s concern about overly optimistic conclusions that could be drawn from the current eDNA literature. One hope for eDNA technology is that it can be used in estimating abundance or population density. Evidence suggests that eDNA measurements correlate with total biomass (Takahara et al., 2012) rather than abundance. We demonstrate a similar relationship between biomass and eDNA shedding rates. Nevertheless, without field testing of these methods and specific survey protocols, we cannot make strong conclusions regarding the technique's field applicability. In our manuscript, we attempted to point out areas in which more research is needed.

Biological Conservation↗
USGS2022

Framework for assessing and mitigating the impacts of offshore wind energy development on marine birds

Offshore wind energy development (OWED) is rapidly expanding globally and has the potential to contribute significantly to renewable energy portfolios. However, development of infrastructure in the marine environment presents risks to wildlife. Marine birds in particular have life history traits that amplify population impacts from displacement and collision with offshore wind infrastructure. Here, we present a broadly applicable framework to assess and mitigate the impacts of OWED on marine birds. We outline existing techniques to quantify impact via monitoring and modeling (e.g., collision risk models, population viability analysis), and present a robust mitigation framework to avoid, minimize, or compensate for OWED impacts. Our framework addresses impacts within the context of multiple stressors across multiple wind energy developments. We also present technological and methodological approaches that can improve impact estimation and mitigation. We highlight compensatory mitigation as a tool that can be incorporated into regulatory frameworks to mitigate impacts that cannot be avoided or minimized via siting decisions or alterations to OWED infrastructure or operation. Our framework is intended as a globally-relevant approach for assessing and mitigating OWED impacts on marine birds that may be adapted to existing regulatory frameworks in regions with existing or planned OWED.

Biological Conservation↗
USGS2024

Tracking data highlight the importance of human-induced mortality for large migratory birds at a flyway scale

Human-induced direct mortality affects huge numbers of birds each year, threatening hundreds of species worldwide. Tracking technologies can be an important tool to investigate temporal and spatial patterns of bird mortality as well as their drivers. We compiled 1704 mortality records from tracking studies across the African-Eurasian flyway for 45 species, including raptors, storks, and cranes, covering the period from 2003 to 2021. Our results show a higher frequency of human-induced causes of mortality than natural causes across taxonomic groups, geographical areas, and age classes. Moreover, we found that the frequency of human-induced mortality remained stable over the study period. From the human-induced mortality events with a known cause ( n = 637), three main causes were identified: electrocution (40.5 %), illegal killing (21.7 %), and poisoning (16.3 %). Additionally, combined energy infrastructure-related mortality (i.e., electrocution, power line collision, and wind-farm collision) represented 49 % of all human-induced mortality events. Using a random forest model, the main predictors of human-induced mortality were found to be taxonomic group, geographic location (latitude and longitude), and human footprint index value at the location of mortality. Despite conservation efforts, human drivers of bird mortality in the African-Eurasian flyway do not appear to have declined over the last 15 years for the studied group of species. Results suggest that stronger conservation actions to address these threats across the flyway can reduce their impacts on species. In particular, projected future development of energy infrastructure is a representative example where application of planning, operation, and mitigation measures can enhance bird conservation.

Biological Conservation↗
USGS2012

Social.Water - A crowdsourcing tool for environmental data acquisition

Remote telemetry has a long history of use for collection of environmental measurements. With the rise of mobile phones and SMS text-messaging capacity, many members of the general pubic carry communications equipment in their pockets at all times. Enabling the general public to provide environmental data through text messages has the potential both to provide additional data to scientific projects and also to raise awareness of the projects through participation. Hydrologic measurements – some of which can be made without training, involve a single measurement, and are often made in rural areas – are well-suited to text-message conveyance. Many other environmental measurements are similarly well-suited for this technology. Social.Water is a software package, written in Python, that collects, parses, and categorizes text messages sent to a dedicated phone number, updates a simple database, and posts both graphical results and the database on the Web. Social.Water was designed as the backend to the Crowdhydrology project and is written in an object-oriented design that makes customization and modification straightforward.

Computers & Geosciences↗
USGS2017

HERA: A dynamic web application for visualizing community exposure to flood hazards based on storm and sea level rise scenarios

The Hazard Exposure Reporting and Analytics (HERA) dynamic web application was created to provide a platform that makes research on community exposure to coastal-flooding hazards influenced by sea level rise accessible to planners, decision makers, and the public in a manner that is both easy to use and easily accessible. HERA allows users to (a) choose flood-hazard scenarios based on sea level rise and storm assumptions, (b) appreciate the modeling uncertainty behind a chosen hazard zone, (c) select one or several communities to examine exposure, (d) select the category of population or societal asset, and (e) choose how to look at results. The application is designed to highlight comparisons between (a) varying levels of sea level rise and coastal storms, (b) communities, (c) societal asset categories, and (d) spatial scales. Through a combination of spatial and graphical visualizations, HERA aims to help individuals and organizations to craft more informed mitigation and adaptation strategies for climate-driven coastal hazards. This paper summarizes the technologies used to maximize the user experience, in terms of interface design, visualization approaches, and data processing.

Computers & Geosciences↗
USGS2020

Acoustic Sediment Estimation Toolbox (ASET): A software package for calibrating and processing TRDI ADCP data to compute suspended-sediment transport in sandy rivers

Quantifying suspended-sediment transport is critical for a variety of disciplines related to the management of water resources. However, the number of gauging stations and monitoring networks in most rivers around the world is insufficient to improve understanding of river dynamics and support water resource management decisions. This is mainly due to the high operational costs and intensive labor involved in traditional sediment measurement techniques, especially in sand bed rivers where coarse material varies spatially in the river cross section. Recently, the acoustic surrogate method has received attention as a potentially accurate surrogate technology for estimating suspended-sediment concentrations. In addition, the acoustic surrogate method, through use of acoustic Doppler current profilers (ADCPs), has the advantage of being able to simultaneously measure the flow velocity field and cross-sectional area when moving-boat measurements are performed. In spite of the important advances made in the implementation of this technique, there are no widely-available, free tools for processing the ADCP acoustic signal cross section measurements which include options to extrapolate velocity and sediment in unmeasured ADCP zones and develop calibrations with physical samples. This paper presents a new software called Acoustic Sediment Estimation Toolbox (ASET), which enables the user to develop a calibration between the acoustic signal collected with a down-looking Teledyne RD Instruments ADCP and sediment concentrations determined using traditional sediment sampling techniques. Moreover, ASET software uses dynamic ADCP measurements to estimate the total suspended-sediment transport through a river cross section. The theoretical framework and data processing routines applied by each module in ASET are presented. Finally, a comparison is made between the results obtained by ASET and by traditional methodologies for computing suspended-sediment transport in a large river system (Paraná River, Argentina).

Computers & Geosciences↗
USGS2015

Sulfate and sulfide sulfur isotopes (δ34S and δ33S) measured by solution and laser ablation MC-ICP-MS: An enhanced approach using external correction

Isotope ratio measurements using a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS) commonly use standard-sample bracketing with a single isotope standard for mass bias correction for elements with narrow-range isotope systems measured by MC-ICP-MS, e.g. Cu, Fe, Zn, and Hg. However, sulfur (S) isotopic composition (δ 34 S) in nature can range from at least − 40 to + 40‰, potentially exceeding the ability of standard-sample bracketing using a single sulfur isotope standard to accurately correct for mass bias. Isotopic fractionation via solution and laser ablation introduction was determined during sulfate sulfur (S sulfate ) isotope measurements. An external isotope calibration curve was constructed using in-house and National Institute of Standards and Technology (NIST) S sulfate isotope reference materials (RM) in an attempt to correct for the difference. The ability of external isotope correction for S sulfate isotope measurements was evaluated by analyzing NIST and United States Geological Survey (USGS) S sulfate isotope reference materials as unknowns. Differences in δ 34 S sulfate between standard-sample bracketing and standard-sample bracketing with external isotope correction for sulfate samples ranged from 0.72‰ to 2.35‰ over a δ 34 S range of 1.40‰ to 21.17‰. No isotopic differences were observed when analyzing S sulfide reference materials over a δ 34 S sulfide range of − 32.1‰ to 17.3‰ and a δ 33 S range of − 16.5‰ to 8.9‰ via laser ablation (LA)-MC-ICP-MS. Here, we identify a possible plasma induced fractionation for S sulfate and describe a new method using external isotope calibration corrections using solution and LA-MC-ICP-MS.

Chemical Geology↗
USGS2021

Terrestrial ecological risk analysis via dietary exposure at uranium mine sites in the Grand Canyon watershed (Arizona, USA)

The U.S. Department of the Interior recently included uranium (U) on a list of mineral commodities that are considered critical to economic and national security. The uses of U for commercial and residential energy production, defense applications, medical device technologies, and energy generation for space vehicles and satellites are known, but the environmental impacts of uranium extraction are not always well quantified. We conducted a screening-level ecological risk analysis based on exposure to mining-related elements via diets and incidental soil ingestion for terrestrial biota to provide context to chemical characterization and exposures at breccia pipe U mines in northern Arizona. Relative risks, calculated as hazard quotients (HQs), were generally low for all biological receptor models. Our models screened for risk to omnivores and insectivores (HQs>1) but not herbivores and carnivores. Uranium was not the driver of ecological risk; arsenic, cadmium, copper, and zinc were of concern for biota consuming ground-dwelling invertebrates. Invertebrate species composition should be considered when applying these models to other mining locations or future sampling at the breccia pipe mine sites. Dietary concentration thresholds (DCTs) were also calculated to understand food concentrations that may lead to ecological risk. The DCTs indicated that critical concentrations were not approached in our model scenarios, as evident in the very low HQs for most models. The DCTs may be used by natural resource and land managers as well as mine operators to screen or monitor for potential risk to terrestrial receptors as mine sites are developed and remediated in the future.

Arizona↗
USGS2024

Determination and prediction of micro scale rare earth element geochemical associations in mine drainage treatment wastes

Acid mine drainage (AMD) has been proposed as a novel source of rare earth elements (REE), a group of elements that includes critical metals for clean energy and modern technologies. REE are sequestered in the Fe–Al–Mn-rich precipitates produced during the treatment of AMD. These AMD solids are typically managed as waste but could be a REE source. Here, results from AMD solids characterization and geochemical modeling are presented to determine the minerals/solid phases that are enriched in REE and identify the mechanism(s) of REE attenuation. AMD solids collected from limestone-based AMD treatment systems were subjected to sequential extraction and synchrotron microprobe analyses to characterize the binding nature of the REE. The results of these analyses indicated REEs were mainly associated with Al or Mn phases. Only selected REE (Gd, Dy) were associated with Fe phases, which were less abundant than Al and Mn phases in analyzed samples. The sequential extractions demonstrated that acidic and/or reducing extractions effectively mobilize REE from the AMD solids evaluated. The observed element associations in solids are consistent with geochemical model results that indicate dissolved REE can be effectively attenuated by adsorption on freshly precipitated Fe, Al, and Mn oxides/hydroxides. The model, which simulates dissolution of CaCO 3 and the precipitation of Fe, Al, and Mn oxides with increased pH, accurately predicts the pH dependent accumulation of dissolved REE with Al, Mn, and Fe oxides/hydroxides in the studied AMD treatment systems. The methods and results presented here can be used to identify conditions favorable for accumulation of REE-enriched AMD solids and possible passive or active treatment(s) to extract REE from AMD. This information can be used to design AMD treatment systems for the recovery of REE and is an opportunity to transform the challenges of addressing polluted mine drainage into an environmental and economic asset.

Pennsylvania↗
USGS2009

Integrated treatment process using a natural Wyoming clinoptilolite for remediating produced waters from coalbed natural gas operations

Coalbed natural gas (CBNG) development in western U.S. states has resulted in an increase in an essential energy resource, but has also resulted in environmental impacts and additional regulatory needs. A concern associated with CBNG development relates to the production of the copious quantities of potentially saline-sodic groundwater required to recover the natural gas, hereafter referred to as CBNG water. Management of CBNG water is a major environmental challenge because of its quantity and quality. In this study, a locally available Na-rich natural zeolite (clinoptilolite) from Wyoming (WY) was examined for its potential to treat CBNG water to remove Na+ and lower the sodium adsorption ratio (SAR, mmol1/2 L- 1/2). The zeolite material was Ca-modified before being used in column experiments. Column breakthrough studies indicated that a metric tonne (1000??kg) of Ca-WY-zeolite could be used to treat 60,000??L of CBNG water in order to lower SAR of the CBNG water from 30 to an acceptable level of 10??mmol1/2 L- 1/2. An integrated treatment process using Na-WY-zeolite for alternately treating hard water and CBNG water was also examined for its potential to treat problematic waters in the region. Based on the results of this study, use of WY-zeolite appears to be a cost-effective water treatment technology for maximizing the beneficial use of poor-quality CBNG water. Ongoing studies are evaluating water treatment techniques involving infiltration ponds lined with zeolite. ?? 2008 Elsevier B.V. All rights reserved.

Applied Clay Science↗
USGS2013

Development of web-based organic petrology photomicrograph atlases and internet resources for professionals and students

With advances in web applications, organic petrography and other related disciplines are in need of updated online resources and educational tools to aid professionals and students in the identification and interpretation of macerals. The U.S. Geological Survey (USGS) Organic Petrology Laboratory along with USGS Eastern Energy Resources Science Center Information Technology staff have developed five web atlases containing images of organic matter in geologic materials: 1. an American Society for Testing and Materials (ASTM) Atlas, 2. an Organic Petrology Taxonomy for International Classification (OPTIC) of Coal Macerals Atlas, 3. an Interactive Gulf Coast Photomicrograph Web Atlas (I-Map), 4. an Organic Material in Shales Atlas (Shale), and 5. an interactive Blue/White/Ultraviolet (UV) Light Atlas (Light). Each web atlas contains images of macerals with associated sample and petrographic data collected by the USGS. These webpages will provide means to preserve and circulate petrographic data collected by the USGS for coal and shale samples from all over the world.

International Journal of Coal Geology↗
USGS2013

Coal resources, reserves and peak coal production in the United States

In spite of its large endowment of coal resources, recent studies have indicated that United States coal production is destined to reach a maximum and begin an irreversible decline sometime during the middle of the current century. However, studies and assessments illustrating coal reserve data essential for making accurate forecasts of United States coal production have not been compiled on a national basis. As a result, there is a great deal of uncertainty in the accuracy of the production forecasts. A very large percentage of the coal mined in the United States comes from a few large-scale mines (mega-mines) in the Powder River Basin of Wyoming and Montana. Reported reserves at these mines do not account for future potential reserves or for future development of technology that may make coal classified currently as resources into reserves in the future. In order to maintain United States coal production at or near current levels for an extended period of time, existing mines will eventually have to increase their recoverable reserves and/or new large-scale mines will have to be opened elsewhere. Accordingly, in order to facilitate energy planning for the United States, this paper suggests that probabilistic assessments of the remaining coal reserves in the country would improve long range forecasts of coal production. As it is in United States coal assessment projects currently being conducted, a major priority of probabilistic assessments would be to identify the numbers and sizes of remaining large blocks of coal capable of supporting large-scale mining operations for extended periods of time and to conduct economic evaluations of those resources.

International Journal of Coal Geology↗