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At least 847 records · Page 47Linked to original sources
USGS2016

Spatial prediction of wheat Septoria leaf blotch (Septoria tritici) disease severity in central Ethiopia

A number of studies have reported the presence of wheat septoria leaf blotch ( Septoria tritici ; SLB) disease in Ethiopia. However, the environmental factors associated with SLB disease, and areas under risk of SLB disease, have not been studied. Here, we tested the hypothesis that environmental variables can adequately explain observed SLB disease severity levels in West Shewa, Central Ethiopia. Specifically, we identified 50 environmental variables and assessed their relationships with SLB disease severity. Geographically referenced disease severity data were obtained from the field, and linear regression and Boosted Regression Trees (BRT) modeling approaches were used for developing spatial models. Moderate-resolution imaging spectroradiometer (MODIS) derived vegetation indices and land surface temperature (LST) variables highly influenced SLB model predictions. Soil and topographic variables did not sufficiently explain observed SLB disease severity variation in this study. Our results show that wheat growing areas in Central Ethiopia, including highly productive districts, are at risk of SLB disease. The study demonstrates the integration of field data with modeling approaches such as BRT for predicting the spatial patterns of severity of a pathogenic wheat disease in Central Ethiopia. Our results can aid Ethiopia's wheat disease monitoring efforts, while our methods can be replicated for testing related hypotheses elsewhere.

Ecological Informatics↗
USGS2016

Spatial and temporal variation in positioning probability of acoustic telemetry arrays: Fine-scale variability and complex interactions

Background As popularity of positional acoustic telemetry systems increases, so does the need to better understand how they perform in real-world applications, where variation in performance can bias study conclusions. Studies assessing variability in positional telemetry system performance have focused primarily on position accuracy, or comparing performance inside and outside the array. Here, we explored spatial and temporal variation in positioning probability within a 140-receiver Vemco Positioning System (VPS) array used to monitor lake trout, Salvelinus namaycush , spawning behavior over 23 km 2 in Lake Huron, North America. Methods Variability in VPS positioning probability was assessed between August and November from 2012 to 2014 using 43 stationary transmitters distributed throughout the array. Various analyses were used to relate positioning probability to number of fish transmitters in the array, wave height, and thermal stratification. We also assessed the prevalence of ‘close proximity detection interference’ (CPDI) in our array by analyzing detection probability of 35 transmitters on collocated receivers. Results Positioning probability of the VPS array varied greatly over time and space. Number of fish transmitters present in the array was a significant driver of reduced positioning probability, especially during lake trout spawning period when the fish were aggregated. Relationships between positioning probability and environmental variables were complex and varied over small spatial and temporal scales. One possible confounding variable was the large range of water depth over which receivers were deployed. Another confounding factor was the high prevalence of CPDI, which decreased exponentially with water depth and was less evident when wave heights were higher than normal. Conclusions Some variables that negatively influenced positioning can be minimized through careful planning (e.g., number of tagged fish released, transmitter power level). However, results suggested that the acoustic environment was highly variable over small spatial and temporal scales in response to complex interactions between many variables. Therefore, models that predict positioning or detection efficiencies as a function of environmental variables may not be attainable in most systems. The best defense against biased study conclusions is incorporation of in situ measures of system performance that allow for retrospective analysis of array performance after a study is completed. Keywords Vemco Positioning System Positional telemetry Performance Detection probability Close proximity detection interference Thermal stratification Wave height Signal code collision

Animal Biotelemetry↗
USGS1998

The North American Amphibian Monitoring Program. [abstract]

The North American Amphibian Monitoring Program has been under development for the past three years. The monitoring strategy for NAAMP has five main prongs: terrestrial salamander surveys, calling surveys, aquatic surveys, western surveys, and atlassing. Of these five, calling surveys were selected as one of the first implementation priorities due to their friendliness to volunteers of varying knowledge levels, relative low cost, and the fact that several groups had already pioneered the techniques involved. While some states and provinces had implemented calling surveys prior to NAAMP, like WI and IL, most states and provinces had little or no history of state/provincewide amphibian monitoring. Thus, the majority of calling survey programs were initiated in the past two years. To assess the progress of this pilot phase, a program review was conducted on the status of the NAAMP calling survey program, and the results of that review will be presented at the meeting. Topics to be discussed include: who is doing what where, extent of route coverage, the continuing random route discussions, quality assurance, strengths and weaknesses of calling surveys, reliability of data, and directions for the future. In addition, a brief overview of the DISPro project will be included. DISPro is a new amphibian monitoring program in National Parks, funded by the Demonstration of Intensive Sites Program (DISPro) through the EPA and NPS. It will begin this year at Big Bend and Shenandoah National Parks. The purpose of the DISPro Amphibian Project will be to investigate relationships between environmental factors and stressors and the distribution, abundance, and health of amphibians in these National Parks. At each Park, amphibian long-term monitoring protocols will be tested, distributions and abundance of amphibians will be mapped, and field research experiments will be conducted to examine stressor effects on amphibians (e.g., ultraviolet radiation, contaminants, acidification).

Book chapter↗
USGS2020

Annotated bibliography of scientific research on greater sage-grouse published from 2015 to 2019

The greater sage-grouse ( Centrocercus urophasianus ; hereafter GRSG) has been a focus of scientific investigation and management action for the past two decades. The 2015 U.S. Fish and Wildlife Service listing determination of “not warranted” was in part due to a large-scale collaborative effort to develop strategies to conserve GRSG populations and their habitat and to reduce threats to both. New scientific information augments existing knowledge and can help inform updates or modifications to existing plans for managing GRSG and sagebrush ecosystems. However, the sheer number of scientific publications can be a challenge for managers tasked with evaluating and determining the need for potential updates to existing planning documents. To assist in this process, the U.S. Geological Survey (USGS) has reviewed and summarized the scientific literature published since January 1, 2015. The first GRSG literature summary was published early in 2018. Here we provide an update to that document by adding summaries of articles published between January 6, 2018 and October 2, 2019. To identify articles and reports published about GRSG, we first conducted a structured search of three reference databases (Web of Science, Scopus, and Google Scholar) using the search term “greater sage-grouse.” We refined the initial list of products by (1) removing duplicates, (2) excluding products that were not published as research or scientific review articles in peer-reviewed journals or as formal technical reports, and (3) retaining only those products for which GRSG or their habitat was a research focus. We summarized the contents of each product by using a consistent structure (background, objectives, methods, location, findings, and implications) and assessed the content of each product relevant to a list of 31 management topics. These topics include GRSG biology and habitat characteristics along with potential management actions, land uses, and environmental factors related to GRSG management and conservation. We also noted which articles/reports created new geospatial data. Our original search, conducted on January 7, 2018, and the application of our criteria, resulted in the inclusion of 169 published products (2 of these products were published corrections to journal articles). This update adds summaries of 69 products published between then and October 2, 2019. The management topics most commonly addressed were GRSG behavior or demographics and GRSG habitat selection or habitat characteristics at broad or site scales. Few products addressed captive breeding, recreation, wild horses and burros, and range management structures (including fences). The management topics with the largest increase in representation between the 2018 GRSG literature summary and this update were GRSG survival and GRSG population estimates or targets, which were each addressed in 16 percent of products in the original literature summary document, but were addressed in 30 and 33 percent, respectively, of newly summarized products. Topics with the largest declines in representation were conifer expansion, - 17 to 10 percent, and new geospatial data, -31 to 21 percent. We include in this annotated bibliography the full citation, Digital Object Identifier (DOI), product summary, and management topics addressed by each product. The online version of this bibliography (https://apps.usgs.gov/gsgbib/index.php) is searchable by topic and location and includes links to journal landing pages for each original publication. A substantial body of literature has been compiled on research explicitly related to the conservation, management, monitoring, and assessment of GRSG. These studies may inform planning and management actions that seek to balance conservation, economic, and social objectives and manage diverse resource uses and values across the western United States. The review process for this product included requesting input on each summary from one or more authors of the original peer-reviewed article or report and a formal review of the entire document by three independent reviewers for the original document and by two independent reviewers for the updated document and, subsequently, the USGS Bureau Approving Official. This process is consistent with USGS Fundamental Science Practices.

Arizona, California, Colorado, Idaho, Kansas, Mont↗
USGS2021

Abundance of a recently discovered Alaskan rhodolith bed in a shallow, seagrass-dominated lagoon

Rhodoliths are important foundation species of the benthic photic zone but are poorly known and rarely studied in Alaska. A bed of Lithothamnion soriferum rhodoliths was discovered in 2008 in Kinzarof Lagoon, Alaska, a shallow-water embayment dominated by eelgrass (Zostera marina). Rhodolith presence and biomass were estimated to assess trends and environmental factors that may influence rhodolith distribution and abundance during 4 years spread over a 12-year period (2008–2010, and 2019). Rhodolith presence and biomass were positively associated with percent seaweed cover, as most rhodoliths and seaweeds occurred in subtidal areas, and negatively associated with percent eelgrass cover. Rhodoliths occurred in two primary areas of the lagoon, a 182-ha core area in a shallow water (mean tide depth of -0.03 m MLLW) tidal channel with low eelgrass density, and a 22-ha outlying area at shallower water depths (>0.2 m MLLW) with moderate to high eelgrass cover. There was no apparent trend in rhodolith biomass over the study period despite wide variation in mean annual estimates. This study establishes a baseline for continued investigations and monitoring of this important benthic resource in Alaska.

Alaska↗
USGS2017

Evaluation and use of U.S. Environmental Protection Agency Clean Watersheds Needs Survey data to quantify nutrient loads to surface water, 1978–2012

Changes in municipal and industrial point-source discharges over time have been an important factor affecting nutrient trends in many of the Nation’s streams and rivers. This report documents how three U.S. Environmental Protection Agency (EPA) national datasets—the Permit Compliance System, the Integrated Compliance Information System, and the Clean Watersheds Needs Survey—were evaluated for use in the U.S. Geological Survey National Water-Quality Assessment project to assess the causes of nutrient trends. This report also describes how a database of total nitrogen load and total phosphorous load was generated for select wastewater treatment facilities in the United States based on information reported in the EPA Clean Watersheds Needs Survey. Nutrient loads were calculated for the years 1978, 1980, 1982, 1984, 1986, 1988, 1990, 1992, 1996, 2000, 2004, 2008, and 2012 based on average nitrogen and phosphorous concentrations for reported treatment levels and on annual reported flow values. The EPA Permit Compliance System (PCS) and Integrated Compliance Information System (ICIS), which monitor point-source facility discharges, together are the Nation’s most spatially comprehensive dataset for nutrients released to surface waters. However, datasets for many individual facilities are incomplete, the PCS/ICIS historical data date back only to 1989, and historical data are available for only a limited number of facilities. Additionally, inconsistencies in facility reporting make it difficult to track or identify changes in nutrient discharges over time. Previous efforts made by the U.S. Geological Survey to “fill in” gaps in the PCS/ICIS data were based on statistical methods—missing data were filled in through the use of a statistical model based on the Standard Industrial Classification code, size, and flow class of the facility and on seasonal nutrient discharges of similar facilities. This approach was used to estimate point-source loads for a single point in time; it was not evaluated for use in generating a consistent data series over time. Another national EPA dataset that is available is the Clean Watersheds Needs Survey (CWNS), conducted every 4 years beginning 1973. The CWNS is an assessment of the capital needs of wastewater facilities to meet the water-quality goals set in the Clean Water Act. Data collected about these facilities include location and contact information for the facilities; population served; flow and treatment level of the facility; estimated capital needs to upgrade, repair, or improve facilities for water quality; and nonpoint-source best management practices. Total nitrogen and total phosphorous load calculations for each of the CWNS years were based on treatment level information and average annual outflow (in million gallons per day) from each of the facilities that had reported it. Treatment levels categories (such as Primary, Secondary, or Advanced) were substituted with average total nitrogen and total phosphorous concentrations for each treatment level based on those reported in literature. The CWNS dataset, like the PCS/ICIS dataset, has years where facilities did not report either a treatment level or an annual average outflow, or both. To fill in the data gaps, simple linear assumptions were made based on each facility’s responses to the survey in years bracketing the data gap or immediately before or after the data gap if open ended. Treatment level and flow data unique to each facility were used to complete the CWNS dataset for that facility.

Scientific Investigations Report↗
USGS2023

Assessment of three methods to evaluate the distribution of submersed aquatic vegetation in western Lake Erie

Submersed aquatic vegetation (SAV) plays an important role in ecosystems. Inventories of SAV spatial distribution and composition are important for monitoring changes in SAV. In this study, we compared three common SAV sampling methods to quantify SAV in western Lake Erie. Aerial imagery of near-shore areas in western Lake Erie was classified using object-based image analysis (OBIA) and evaluated against field-based surveys using single-beam sonar or rake samples. To assess variation among methods, data were assigned either vegetation ‘presence’ or ‘absence’ and compared for simple correspondence and agreement (Cohen’s Kappa, κ ). The two field-based methods had the highest correspondence at 78% ( n = 782) and the highest κ = 0.545. Correspondence between OBIA and rake surveys was 69% ( n = 245) and κ = 0.36. Correspondence between OBIA and hydroacoustics was the lowest of 54% ( n = 30,768) with an agreement of κ = 0.17. Environmental factors such as water turbidity may have played a role in reduced agreement between OBIA and field methods. Determining the optimal method or combination of methods will depend upon research goals, effort, and cost, but each method can provide reliable SAV information for resource management.

Michigan, Ohio↗
USGS2012

Evidence, models, conservation programs and limits to management

Walsh et al. (2012) emphasized the importance of obtaining evidence to assess the effects of management actions on state variables relevant to objectives of conservation programs. They focused on malleefowl Leipoa ocellata, ground-dwelling Australian megapodes listed as vulnerable. They noted that although fox Vulpes vulpes baiting is the main management action used in malleefowl conservation throughout southern Australia, evidence of the effectiveness of this action is limited and currently debated. Walsh et al. (2012) then used data from 64 sites monitored for malleefowl and foxes over 23 years to assess key functional relationships relevant to fox control as a conservation action for malleefowl. In one set of analyses, Walsh et al. (2012) focused on two relationships: fox baiting investment versus fox presence, and fox presence versus malleefowl population size and rate of population change. Results led to the counterintuitive conclusion that increases in investments in fox control produced slight decreases in malleefowl population size and growth. In a second set of analyses, Walsh et al. (2012) directly assessed the relationship between investment in fox baiting and malleefowl population size and rate of population change. This set of analyses showed no significant relationship between investment in fox population control and malleefowl population growth. Both sets of analyses benefited from the incorporation of key environmental covariates hypothesized to influence these management relationships. Walsh et al. (2012) concluded that "in most situations, malleefowl conservation did not effectively benefit from fox baiting at current levels of investment." In this commentary, I discuss the work of Walsh et al. (2012) using the conceptual framework of structured decision making (SDM). In doing so, I accept their analytic results and associated conclusions as accurate and discuss basic ideas about evidence, conservation and limits to management.

Animal Conservation↗
USGS2011

Integrating estimates of ecosystem services from conservation programs and practices into models for decision makers

Most government agencies involved in land management are seeking consistent approaches to evaluate the effects of specific management actions on ecological processes and concurrent changes on ecosystem services. This is especially true within the context of anthropogenic influences, such as land use and climate change. The Conservation Effects Assessment Project—Wetlands National Component (CEAP–Wetlands) was developed by the U.S. Department of Agriculture (USDA) to evaluate effects of conservation practices on ecosystem services including carbon sequestration for climate stability, groundwater recharge, runoff and flood attenuation, water storage, nutrient and contaminant retention, and wildlife habitat. A primary purpose of CEAP–Wetlands is to provide science‐based information in an adaptive monitoring framework for use by the USDA to facilitate policy and management decisions, and to document effects of conservation programs and practices to the federal Office of Management and Budget. Herein, we propose a modeling framework to allow estimation of conservation practice and program effects on various ecosystem services at different temporal and spatial scales. This modeling approach provides the broad view needed by decision‐makers to avoid unintended negative environmental outcomes, and to communicate to society the positive effects of conservation actions on a broad suite of ecosystem services.

Ecological Applications↗
USGS2022

A decade of monitoring micropollutants in urban wet-weather flows: What did we learn?

Urban wet-weather discharges from combined sewer overflows (CSO) and stormwater outlets (SWO) are a potential pathway for micropollutants (trace contaminants) to surface waters, posing a threat to the environment and possible water reuse applications. Despite large efforts to monitor micropollutants in the last decade, the gained information is still limited and scattered. In a metastudy we performed a data-driven analysis of measurements collected at 77 sites (683 events, 297 detected micropollutants) over the last decade to investigate which micropollutants are most relevant in terms of 1) occurrence and 2) potential risk for the aquatic environment, 3) estimate the minimum number of data to be collected in monitoring studies to reliably obtain concentration estimates, and 4) provide recommendations for future monitoring campaigns. We highlight micropollutants to be prioritized due to their high occurrence and critical concentration levels compared to environmental quality standards. These top-listed micropollutants include contaminants from all chemical classes (pesticides, heavy metals, polycyclic aromatic hydrocarbons, personal care products, pharmaceuticals, and industrial and household chemicals). Analysis of over 30,000 event mean concentrations shows a large fraction of measurements (> 50%) were below the limit of quantification, stressing the need for reliable, standard monitoring procedures. High variability was observed among events and sites, with differences between micropollutant classes. The number of events required for a reliable estimate of site mean concentrations (error bandwidth of 1 around the “true" value) depends on the individual micropollutant. The median minimum number of events is 7 for CSO (2 to 31, 80%-interquantile) and 6 for SWO (1 to 25 events, 80%-interquantile). Our analysis indicates the minimum number of sites needed to assess global pollution levels and our data collection and analysis can be used to estimate the required number of sites for an urban catchment. Our data-driven analysis demonstrates how future wet-weather monitoring programs will be more effective if the consequences of high variability inherent in urban wet-weather discharges are considered.

Water Research↗
USGS1996

Summary of hydrogeologic controls on ground-water flow at the Nevada Test Site, Nye County, Nevada

The underground testing of nuclear devices has generated substantial volumes of radioactive and other chemical contaminants below ground at the Nevada Test Site (NTS). Many of the more radioactive contaminants are highly toxic and are known to persist in the environment for thousands of years. In response to concerns about potential health hazards, the U.S. Department of Energy, under its Environmental Restoration Program, has made NTS the subject of a long-term investigation. Efforts supported through the U.S. Department of Energy program will assess whether byproducts of underground testing pose a potential hazard to the health and safety of the public and, if necessary, will evaluate and implement steps to remediate any of the identified dangers. Test-generated contaminants have been introduced over large areas and at variable depths above and below the water table throughout NTS. Evaluating the risks associated with these byproducts of underground testing presupposes a knowledge of the source, transport, and potential receptors of these contaminants. Ground-water flow is the primary mechanism by which contaminants can be transported significant distances away from the initial point of injection. Flow paths between contaminant sources and potential receptors are separated by remote areas that span tens of miles. The diversity and structural complexity of the rocks along these flow paths complicates the hydrology of the region. Although the hydrology has been studied in some detail, much still remains uncertain about flow rates and directions through the fractured-rock aquifers that transmit water great distances across this arid region. Unique to the hydrology of NTS are the effects of underground testing, which severely alter local rock characteristics and affect hydrologic conditions throughout the region. Any assessment of the risk must rely in part on the current understanding of ground-water flow, and the assessment will be only as good as the understanding itself. This report summarizes what is known and inferred about ground-water flow throughout the NTS region. The report identifies and updates what is known about some of the major controls on ground-water flow, highlights some of the uncertainties in the current understanding, and prioritizes some of the technical needs as related to the Environmental Restoration Program. An apparent deficiency in the current understanding is a lack of knowledge about flow directions and rates away from major areas of testing. Efforts are necessary to delineate areas of downgradient flow and to identify factors that constrain and control flow within these areas. These efforts also should identify the areas most critical to gaining detailed understanding and to establishing long-term monitoring sites necessary for effective remediation.

Nevada↗
USGS2020

Fisheries research and monitoring activities of the Lake Erie Biological Station, 2019

A comprehensive understanding of fish populations and their interactions is the cornerstone of modern fishery management and the basis for Fish Community Goals and Objectives for Lake Erie (Ryan et al. 2003). This report is responsive to U.S. Geological Survey (USGS) obligations via Memorandum of Understanding (MOU) with the Great Lakes Council of Lake Committees (CLC) to provide scientific information in support of fishery management. Goals for the USGS Great Lakes Deepwater Fish Assessment and Ecological Studies in 2019 were to monitor long-term changes in the fish community and population dynamics of key fishes of interest to management agencies. Specific to Lake Erie, expectations of this agreement were sustained investigations of native percids, forage (prey) fish populations, and Lake Trout. Our 2019 deepwater program operations began in April and concluded in December, and utilized trawl, gillnet, hydroacoustic, lower trophic sampling, and telemetry methods. This work resulted in 88 bottom trawls covering 65 ha of lake-bottom and catching 24,140 fish totaling 3,622 kg during three separate trawl surveys in the West and Central basins of Lake Erie. Overnight gillnet sets (n=44) for cold water species were performed at 42 unique locations in the West and East basins of Lake Erie. A total of 8.0 km of gillnet was deployed during these surveys, which caught 286 fish, 114 of which were native coldwater species: Lake Trout, Burbot, and Lake Whitefish. USGS hydroacoustic surveys in 2019 produced 240 km of transects, and lower trophic sampling provided data from zooplankton samples (n=21) and water quality profiles (n=21) to populate a database maintained by the Ontario Ministry of Natural Resources and Forestry (OMNRF), Ohio Division of Natural Resources (ODNR), Michigan Division of Natural Resources (MDNR), Pennsylvania Fish and Boat Commission (PFBC), and New York State Department of Environmental Conservation (NYSDEC). USGS also assisted CLC member agencies with deployment and maintenance of the Great Lakes Acoustic Telemetry Observation System (GLATOS) throughout all three Lake Erie sub-basins, supporting multiple coordinated telemetry investigations. In 2019, Lake Trout investigations included annual gill net surveys and acoustic telemetry of spawning migration and habitat use in coordination with OMNRF, NYSDEC, and PFBC. Results from Lake Trout investigations were reported in the Coldwater Task Group annual report to the Great Lakes Fishery Commission (GLFC) and the CLC (Coldwater Task Group 2020). Likewise, interagency forage fish assessments conducted with hydroacoustics were summarized and reported in the Forage Task Group annual report (Forage Task Group 2020). This report presents biomass-based summaries of fish communities in western Lake Erie derived from USGS bottom trawl surveys conducted from 2013 to 2019 during June and September. The survey design provided temporal and spatial coverage that did not exist in the historic interagency trawl database, and thus complemented the August ODNR-OMNRF effort to reinforce stock assessments with more robust data. Analyses herein evaluated trends in: total biomass, abundance of dominant predator and forage species, non-native species composition, biodiversity and community structure. Data from this effort can be explored interactively online (https://lebs.shinyapps.io/western-basin/), and are accessible for download (https://doi.org/10.5066/P9LL6YOR, Keretz et al. 2020). Annual survey data are added to these sources as the data become available.

Lake Erie↗
USGS2024

Tissue distribution and temporal and spatial assessment of per- and polyfluoroalkyl substances (PFAS) in smallmouth bass (Micropterus dolomieu) in the mid-Atlantic United States

Per- and polyfluoroalkyl substances (PFAS) have become an environmental issue worldwide. A first step to assessing potential adverse effects on fish populations is to determine if concentrations of concern are present in a region and if so, in which watersheds. Hence, plasma from adult smallmouth bass Micropterus dolomieu collected at 10 sites within 4 river systems in the mid-Atlantic region of the United States, from 2014 to 2019, was analyzed for 13 PFAS. These analyses were directed at better understanding the presence and associations with land use attributes in an important sportfish. Four substances, PFOS, PFDA, PFUnA, and PFDoA, were detected in every plasma sample, with PFOS having the highest concentrations. Sites with mean plasma concentrations of PFOS below 100 ng/ml had the lowest percentage of developed landcover in the upstream catchments. Sites with moderate plasma concentrations (mean PFOS concentrations between 220 and 240 ng/ml) had low (< 7.0) percentages of developed land use but high (> 30) percentages of agricultural land use. Sites with mean plasma concentrations of PFOS > 350 ng/ml had the highest percentage of developed land use and the highest number PFAS facilities that included military installations and airports. Four of the sites were part of a long-term monitoring project, and PFAS concentrations of samples collected in spring 2017, 2018, and 2019 were compared. Significant annual differences in plasma concentrations were noted that may relate to sources and climatic factors. Samples were also collected at two sites for tissue (plasma, whole blood, liver, gonad, muscle) distribution analyses with an expanded analyte list of 28 PFAS. Relative tissue distributions were not consistent even within one species of similar ages. Although the long-chained legacy PFAS were generally detected more frequently and at higher concentrations, emerging compounds such as 6:2 FTS and GEN X were detected in a variety of tissues.

Delaware, Maryland, New York, Pennsylvania, Virgin↗
USGS1996

Assessment of water quality in the South Indian River Water Control District, Palm Beach County, Florida, 1989-94

The South Indian River Water Control District is located in an area of northern Palm Beach County, Fla., where many residents must rely on private wells for domestic water supplies and individual septic tanks for waste disposal. As a result, contamination of the surficial aquifer system and availability of a potable water supply have become of increasing concern. To address this concern, the U.S. Geological Survey, in cooperation with the South Indian River Water Control District, conducted a study to assess ground-water and surface-water quality in the District from 1989 to 1994. The study consisted of water-quality monitoring at 11 wells and 14 surface-water sites located within the District. Water samples were analyzed for major inorganic constituents and physical characteristics, trace metals, nitrogen and phosphorus species, and synthetic organic compounds. The predominant water type within the South Indian River Water Control District is calcium bicarbonate; however, mixed-ion type water and sodium bicarbonate type water also exist in varying amounts. Sodium chloride type water is present in the western areas of the District due to incompletely flushed residual sea water. Results of the study indicated that concentrations of most constituents were within State drinking-water standards as established by the Florida Department of Environmental Protection, but concentrations of certain constituents occasionally exceeded drinking-water standards in some ground-water and surface-water samples. Sodium and chloride concentrations exceeded the standards in ground water at two wells, dissolved-solids concentrations at five ground-water wells and one surface-water site, and color values at all 11 ground-water wells and all 14 surface-water sites. Other constituents also exhibited concentrations that exceeded drinking-water standards. Cadmium and zinc concentrations exceeded the standards in ground water at one well, and lead concentrations exceeded the standard in ground water at five wells. Nitrogen and phosphorus specie concentrations did not exceed respective drinking-water standards in any ground-water or surface-water samples. Additionally, organic compounds were not detected at four surface-water sites monitored for National Pollutant Discharge Elimination System constituents. Several synthetic organic compounds were detected at or above 50 micrograms per liter in water samples collected from six ground-water wells and three surface-water sites.

Florida↗
USGS2003

Assessment of selected inorganic constituents in streams in the Central Arizona Basins study area, Arizona and northern Mexico, through 1998

Stream properties and water-chemistry constituent concentrations from data collected by the National Water-Quality Assessment and other U.S. Geological Survey water-quality programs were analyzed to (1) assess water quality, (2) determine natural and human factors affecting water quality, and (3) compute stream loads for the surface-water resources in the Central Arizona Basins study area. Stream temperature, pH, dissolved-oxygen concentration and percent saturation, and dissolved-solids, suspended-sediment, and nutrient concentration data collected at 41 stream-water quality monitoring stations through water year 1998 were used in this assessment. Water-quality standards applicable to the stream properties and water-chemistry constituent concentration data for the stations investigated in this study generally were met, although there were some exceedences. In a few samples from the White River, the Black River, and the Salt River below Stewart Mountain Dam, the pH in reaches designated as a domestic drinking water source was higher than the State of Arizona standard. More than half of the samples from the Salt River below Stewart Mountain Dam and almost all of the samples from the stations on the Central Arizona Project Canal—two of the three most important surface-water sources used for drinking water in the Central Arizona Basins study area—exceeded the U.S. Environmental Protection Agency drinking water Secondary Maximum Contaminant Level for dissolved solids. Two reach-specific standards for nutrients established by the State of Arizona were exceeded many times: (1) the annual mean concentration of total phosphorus was exceeded during several years at stations on the main stems of the Salt and Verde Rivers, and (2) the annual mean concentration of total nitrogen was exceeded during several years at the Salt River near Roosevelt and at the Salt River below Stewart Mountain Dam. Stream properties and water-chemistry constituent concentrations were related to streamflow, season, water management, stream permanence, and land and water use. Dissolved-oxygen percent saturation, pH, and nutrient concentrations were dependent on stream regulation, stream permanence, and upstream disposal of wastewater. Seasonality and correlation with streamflow were dependant on stream regulation, stream permanence, and upstream disposal of wastewater. Temporal trends in streamflow, stream properties, and water-chemistry constituent concentrations were common in streams in the Central Arizona Basins study area. Temporal trends in the streamflow of unregulated perennial reaches in the Central Highlands tended to be higher from 1900 through the 1930s, lower from the 1940s through the 1970s, and high again after the 1970s. This is similar to the pattern observed for the mean annual precipitation for the Southwestern United States and indicates long-term trends in flow of streams draining the Central Highlands were driven by long-term trends in climate. Streamflow increased over the period of record at stations on effluent-dependent reaches as a result of the increase in the urban population and associated wastewater returns to the Salt and Gila Rivers in the Phoenix metropolitan area and the Santa Cruz River in the Tucson metropolitan area. Concentrations of dissolved solids decreased in the Salt River below Stewart Mountain Dam and in the Verde River below Bartlett Dam. This decrease represents an improvement in the water quality and resulted from a concurrent increase in the amount of runoff entering the reservoirs. Stream loads of water-chemistry constituents were compared at different locations along the streams with one another, and stream loads were compared to upstream inputs of the constituent from natural and anthropogenic sources to determine the relative importance of different sources and to determine the fate of the water-chemistry constituent. Of the dissolved solids transported into the Basin and Range Lowlands each year from the Central Arizona Project Canal and from streams draining the Central Highlands, about 1.2 billion kilograms accumulated in the soil, unsaturated zone, and aquifers in agricultural and urban areas as a result of irrigating crops and urban vegetation. Stream loads of phosphorus decreased from the 91st Avenue Wastewater-Treatment Plant downstream to the Gila River at Gillespie Dam, probably as a result of adsorption of phosphorus to the streambed sediments. In this same reach, stream loads of nitrogen increased, most likely because of inputs from fertilizers. The annual mass of nitrogen and phosphorus input to developed basins from quantifiable sources was much larger than the mass input to basins that had little or no municipal or agricul-tural development. These computed inputs exclude the mass of nitrogen and phosphorus from sources such as geologic formations and soils that could not be quantified. The quantifiable annual inputs of nitrogen and phosphorus for the upper Salt River Basin and the upper Verde River Basin were similar to those for the West Clear Creek Basin. This similarity suggests that the small amount of municipal and agricultural development in the upper Salt River and the upper Verde River Basins did not greatly change the basin input flux. For basins with minimal urban and agricultural development, the largest quantifiable source of nitrogen was precipitation, and the largest source of phosphorus was human bodily waste treated by sewer and septic systems. This was in contrast to developed basins, for which fertilizer was the largest quantifiable source of both nutrients. For most basins examined, quantifiable inputs of nitrogen and phosphorus from nonpoint sources were greater than inputs from point sources. This relation emphasizes the importance of land- and water-management policies that protect surface-water resources from nonpoint sources of nutrients as well as from point sources. The amount of nitrogen and phosphorus transpor-ted out of basins was a small fraction of the total for the quantifiable inputs. This result indicated that most of the nutrients input to basins were not transported out of the basins in surface water, but rather were transported to the subsurface (the soil, unsaturated zone, or aquifer), released to the atmosphere (such as volatilized ammonia), or incorporated into the biomass.

Central Arizona Basins study area↗
USGS2017

Natural resource inventory and monitoring for Ulaan Taiga Specially Protected Areas—An assessment of needs and opportunities in northern Mongolia

Between 1997 and 2011, Mongolia established three specially protected areas in the north-central part of the country to protect various high-value resources. These areas are jointly referred to as the Ulaan Taiga Specially Protected Areas. In accordance with the goals of the draft general management plan, this report identifies options for initiating an inventory and monitoring program for the three protected areas. Together, the three areas comprise over 1.5 million hectares of mountainous terrain west of Lake Hovsgol and bordering the Darkhad Valley. The area supports numerous rare ungulates, endangered fish, and over 40 species of threatened plants. Illegal mining, illegal logging, and poaching pose the most immediate threats to resources. As a first step, a review of published literature would inform natural resource management at the Ulaan Taiga Specially Protected Areas because it would inform other inventories. Vegetation classification and mapping also would inform other inventory efforts because the process incorporates geographic analysis to identify environmental gradients, fine-scale sampling that captures species composition and structure, and landscape-scale results that represent the variety and extent of habitats for various organisms. Mapping using satellite imagery reduces the cost per hectare. Following a determination of existing knowledge, field surveys of vertebrates and vascular plants would serve to build species lists and fill in gaps in existing knowledge. For abiotic resources, a focus on monitoring air quality, evaluating and monitoring water quality, and assembling and storing weather data would provide information for correlating resource response status with changing environmental conditions. Finally, we identify datasets that, if incorporated into a geographic information system, would inform resource management. They include political boundaries, infrastructure, topography, surficial geology, hydrology, fire history, and soils. In terms of tracking high-value resources, vegetation monitoring at the plot scale would provide a basis for detecting change in such characteristics as plant species composition, vegetation structure, and productivity that are associated with landscape-scale factors such as climate change or biotic interactions. Continued population monitoring of rare ungulates, particularly argali or wild sheep ( Ovis ammon ), would provide information on how populations are responding to natural and anthropogenic stressors. Siberian taimen ( Hucho taimen ) also is an important monitoring target given ongoing threats of poaching and climate change.

Ulaan Taiga Specially Protected Areas↗
USGS2026

Assessment of groundwater quantity and quality contributions to Lake Huron

Lake Huron, one of the five Great Lakes, borders the United States and Canada, with Michigan as the only U.S. State on its shoreline. Like other freshwater lakes, it faces water-quality challenges from nutrients and chemicals applied across its drainage basin. Although past studies focused on surface-water sources, groundwater contributions remain less understood. To address this gap, the U.S. Geological Survey, as part of the Cooperative Science and Monitoring Initiative, classified drainage basins to Lake Huron into eight hydrogeologic zones based on bedrock rock type and glacial sediment transmissivity. Utilizing existing data and empirical field data, we quantified groundwater discharge and identified areas of concern for loading of chloride and nitrate to Lake Huron. Groundwater contributions, including indirect and shoreline discharge, ranged from 5.8 to 11.5 inches annually, totaling 1.9 cubic miles and 0.09 cubic mile, respectively. Hydrogeologic zones with higher glacial sediment transmissivity yielded greater indirect groundwater discharge. Chloride levels above the U.S. Environmental Protection Agency’s 250-mg/L recommendation were mainly in the Saginaw lowlands, whereas nitrate above the 10-mg/L standard was rare—found in only 11 wells. Together, the analysis of where groundwater discharge is occurring in the Lake Huron Basin and the identification of areas with potential groundwater-quality concerns can help prioritize areas that are critical to protecting the long-term health of Lake Huron.

Michigan↗
USGS2016

Summary of environmental flow monitoring for the Sustainable Rivers Project on the Middle Fork Willamette and McKenzie Rivers, western Oregon, 2014–15

This report presents the results of an ongoing environmental flow monitoring study by The Nature Conservancy (TNC), U.S. Army Corps of Engineers (USACE), and U.S. Geological Survey in support of the Sustainable Rivers Project (SRP) of TNC and USACE. The overarching goal of this study is to evaluate and characterize relations between streamflow, geomorphic processes, and black cottonwood ( Populus trichocarpa ) recruitment on the Middle Fork Willamette and McKenzie Rivers, western Oregon, that were hypothesized in earlier investigations. The SRP can use this information to plan future monitoring and scientific investigations, and to help mitigate the effects of dam operations on streamflow regimes, geomorphic processes, and biological communities, such as black cottonwood forests, in consultation with regional experts. The four tasks of this study were to: Compare the hydrograph from Water Year (WY) 2015 with hydrographs from WYs 2000–14 and the SRP flow recommendations, Assess short-term and system-wide changes in channel features and vegetation throughout the alluvial valley section of the Middle Fork Willamette River (2005–12), Examine changes in channel features and vegetation over two decades (1994–2014) for two short mapping zones on the Middle Fork Willamette and McKenzie Rivers, and Complete a field investigation of summer stage and the growth of black cottonwood and other vegetation on the Middle Fork Willamette and McKenzie Rivers in summer 2015.

Oregon↗