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A digital raster graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) topographic map. The scanned image includes all map collar information. The image inside the map neatline is georeferenced to the surface of the Earth. The DRG can be used to collect, review, and revise other digital data, especially digital line graphs (DLG).
Alaska Natives depend on local natural resources for nutritional and, for many, spiritual health. As a result, public health in Alaska is strongly influenced by the relationship between people and their surrounding physical, chemical, and biological environments. Alaska is vast with diverse wildlife and plant communities that are valued as subsistence foods (fig. 1). These resources are supported by equally diverse ecosystems and their underpinning landforms and geologies. The U.S. Geological Survey (USGS) is attempting to integrate physical, chemical, and biological information to better describe current (2013) environments and project scenarios for the future. Integrating ecological data into the public health dialogue is challenging for the more than 280 rural communities of Alaska. This fact sheet reviews a recent USGS effort, the Geographic Information System (GIS) Native Health Project, to better incorporate scientific information into such dialogue.
Introduction: This document outlines a research framework for water resource managers and land-use planners in the four-state Connecticut River Watershed (CRW). It specifically focuses on developing the decision-support tools and data needed by managers in the watershed. The purpose of the Science Framework is to identify critical research issues and information required to better equip managers to make decisions on desirable changes in the CRW. This Science Framework is the result of a cooperative project between the U.S. Geological Survey (USGS), the University of Massachusetts at Amherst (UMass-Amherst), and the U.S. Fish and Wildlife Service (FWS). The cooperative project was guided by a Science Steering Committee (SC) and included several focus groups, a 70-person workshop in September 2004, and an open collaborative process by which the workshop outcomes were synthesized, written up, and then progressively refined through peer review. This document is the product of that collaborative process.
Pursuant to the Presidential Executive Order (EO) No. 13817, “A Federal Strategy to Ensure Secure and Reliable Supplies of Critical Minerals,” the Secretary of the Interior, in coordination with the Secretary of Defense, and in consultation with the heads of other relevant executive departments and agencies, was tasked with developing and submitting a draft list of minerals defined as “critical minerals” to the Federal Register within 60 days of the issue of the EO (December 20, 2017). Based on an analysis by the U.S. Geological Survey and other U.S. Government agencies, using multiple criteria, 35 minerals or mineral material groups have been identified that are currently (February 2018) considered critical. These include the following: aluminum (bauxite), antimony, arsenic, barite, beryllium, bismuth, cesium, chromium, cobalt, fluorspar, gallium, germanium, graphite (natural), hafnium, helium, indium, lithium, magnesium, manganese, niobium, platinum group metals, potash, rare earth elements group, rhenium, rubidium, scandium, strontium, tantalum, tellurium, tin, titanium, tungsten, uranium, vanadium, and zirconium. The categorization of minerals as critical may change during the course of the review process and is thus provisional.
The 2006 eruption of Augustine Volcano, Alaska, generated more than 3,500 earthquakes in a month-long time frame bracketing the most explosive period of activity. We examine two quantitative tools that, in retrospective analysis, were excellent indicators of imminent eruption. The first tool, referred to as the frequency index ( FI ), is based on a simple ratio of high- and low-frequency energy in an earthquake seismogram. It is a metric that allows us to quantify the differences between the canonical high-frequency, hybrid, and low-frequency volcanic earthquakes. FI values greater than -0.4 indicate earthquakes classically referred to as high-frequency or volcano-tectonic events. FI values less than -1.3 correspond to events usually referred to as low-frequency earthquakes. Because the FI is based on a ratio and not a spectral peak, hybrid earthquakes are successfully assigned FI values intermediate to these two classes. In this eruption, we find a remarkable correlation between events with FI less than -1.8 and explosive eruptions. The second tool we examine is based on repeating seismic waveforms identified through waveform cross-correlation. Although the vast majority of earthquakes during this eruption have unique waveforms, subsets of events exhibiting a high degree of similarity occur and are closely tied to explosive eruption events. Of the 13 large explosion events, seven were preceded by clusters of highly similar earthquakes. We apply the FI and correlation tools together to identify changes in high- and low-frequency earthquake occurrences and examine their relations to the precursory, explosive, and continuous phases of the eruption. We find that earthquakes that have low FI values and earthquakes exhibiting high degrees of similarity occur almost exclusively within hours of explosive eruptions and postulate that they occur as a result of the final ascent of magma in the volcanic edifice. Because neither of these methods requires analyst-reviewed earthquake locations, we believe that they have considerable potential as automated real-time volcano monitoring tools.
More than 800 wells in the glacial aquifer system of the Northern United States were sampled for arsenic as part of U.S. Geological Survey National Water-Quality Assessment (NAWQA) studies during 1991-2003. Elevated arsenic concentrations (greater than or equal to 10 micrograms per liter) were detected in 9 percent of samples. Elevated arsenic concentrations were associated with strongly reducing conditions. Of the samples classified as iron reducing or sulfate reducing, arsenic concentrations were elevated in 19 percent. Of the methanogenic samples, arsenic concentrations were elevated in 45 percent. In contrast, concentrations of arsenic were elevated in only 1 percent of oxic samples. Arsenic concentrations were also related to ground-water age. Elevated arsenic concentrations were detected in 34 percent of old waters (recharged before 1953) as compared to 4 percent of young waters (recharged since 1953). For samples classified as both old and methanogenic, elevated arsenic concentrations were detected in 62 percent of samples, as compared to 1 percent for samples classified as young and oxic. Arsenic concentrations were also correlated with well depth and concentrations of several chemical constituents, including (1) constituents linked to redox processes and (2) anions or oxyanions that sorb to iron oxides. Observations from the glacial aquifer system are consistent with the idea that the predominant source of arsenic is iron oxides and the predominant mechanism for releasing arsenic to the ground water is reductive desorption or reductive dissolution. Arsenic is also released from iron oxides under oxic conditions, but on a more limited basis and at lower concentrations. Logistic regression was used to investigate the relative significance of redox, ground-water age, depth, and other water-quality constituents as indicators of elevated arsenic concentrations in the glacial aquifer system. The single variable that explained the greatest amount of variation in the data was redox. Multivariate models that included a redox variable overestimated the percentage of samples with elevated arsenic concentrations because, even though elevated arsenic concentrations were associated with strongly reducing samples, not all strongly reducing samples had elevated arsenic concentrations. Arsenic concentrations and redox conditions differed among four broad areas of the glacial aquifer system. For the East, Central, and West-Central north areas, there was a trend of increasing arsenic concentrations that corresponded to an increase in reducing conditions. For the West-Central south area, arsenic concentrations in oxic samples were higher than for the other areas, possibly because of high concentrations of orthophosphate, which is linked to desorption of arsenic from iron oxides under oxic conditions. The observed differences in arsenic concentrations among broad areas of the glacial aquifer system were generally consistent with a conceptual model developed by Smedley and Kinniburg, who studied or reviewed studies of widespread arsenic contamination in Bangladesh, India, China, Vietnam, Hungary, Argentina, northern Chile and the Southwestern United States.
The widespread extent and continued construction of seawalls and bulkheads on Puget Sound's beaches has emerged as a significant issue in shoreline management and coastal restoration in the region. Concerns about the impacts of shoreline armoring and managing the potential risks to coastal property are in many ways similar to those in other places, but Puget Sound also poses unique challenges related to its sheltered setting, glacially formed geology, rich estuarine ecology, and historical development pattern. The effects of armoring on shorelines are complex, involving both physical and biological science and requiring consideration of the cumulative impacts of small-scale activities over large scales of space and time. In addition, the issue is controversial, as it often places strongly held private interests in protecting shoreline property against broad public mandates to preserve shorelines for public uses and to protect environmental resources. Communities making difficult decisions about regulating shoreline activities and prioritizing restoration projects need to be informed by the best science available. To address these issues, a scientific workshop was convened in May 2009, specifically to bring local and national experts together to review the state of the science regarding the physical and biological impacts of armoring on sheltered shorelines such as those of Puget Sound.
The Watershed Boundary Dataset (WBD) is a seamless, national hydrologic unit dataset developed using the guidelines and specifications outlined in this document. A hydrologic unit defines the areal extent of surface-water drainage to an outlet point on a dendritic stream network or to outlet points where the stream network is not dendritic. A hydrologic unit may represent all or only part of the total drainage area to the outlet point so that multiple hydrologic units may be required to define the entire drainage area for a given outlet. Hydrologic unit boundaries in the WBD are determined on the basis of topographic, hydrologic, and other relevant landscape characteristics without regard for administrative, political, or jurisdictional boundaries. The WBD seamlessly represents hydrologic units at six required and two optional hierarchical levels mapped at a minimum of 1:24,000-scale in the United States, except for in Hawaii, the Caribbean, and the Pacific Islands, which are at 1:25,000-scale, and in Alaska, where the data range from the minimum required 1:24,000-scale to 1:63,360-scale. Hydrologic units in the WBD provide a standardized base for water-resources organizations to locate, store, retrieve, and exchange hydrologic data; to index and inventory hydrologic data and information; to catalog water-data acquisition activities; and to use in a variety of other applications. The specifications and procedures established in this document are intended to provide guidelines and best practices to local, regional, and national partners for delineating and updating the hydrologic units of the WBD. Maintaining the WBD using consistent practices improves watershed management through efficient sharing of information and resources and by ensuring that digital geographic data can be used with other related geographic information system data. Edits and additions to the hydrologic units are reviewed against this specification prior to inclusion to the national WBD.
In 1991 the Trinity River Basin study unit was among the first 20 study units in which work began under full-scale program implementation of the National Water-Quality Assessment Program. A retrospective assessment was undertaken to review and analyze existing pesticide data and related environmental factors. Population and land-use data indicate human modifications to the landscape and hydrologic system of the study area during the period 1968–91. A variety of crops treated with pesticides were identified, with wheat and cotton accounting for the largest number of acres treated annually (541,250 and 519,870 acres, respectively). Agricultural-use estimates for the later period covered by this report (1988–90) indicate that 105 different pesticides were used and that 24 pesticides accounted for 75 percent of average agricultural use in the study area. Sorghum was treated by the largest number of the 24 mostused pesticides, and cotton was treated by the second largest number of those pesticides. Dimethoate and methyl parathion were the most heavily used of the organophosphate class pesticides. The herbicide 2,4–D was the most heavily used chlorophenoxy pesticide. Carbamate pesticides are used extensively in the study area, with carbaryl, carbofuran, methomyl, and thiodicarb accounting for the majority of the use of this class of pesticide. Miscellaneous pesticides included alachlor, arsenic acid, picloram, and glyphosate, among others. The data indicate that herbicide use generally is proportionally higher in the study area than in the Nation, and that insecticide use in the study area generally is proportionally lower than in the Nation. Eight different agencies collected the waterquality data used in this report. Samples were collected by all agencies at a combined total of 155 surface-water sites and 121 ground-water sites. The sampled media included water, bed sediment, and tissues of fish and other aquatic wildlife. Some 273 samples for analysis of the herbicide 2,4–D were collected as part of the city of Arlington’s data-collection program. The herbicide was detected in 74 percent of the samples, but none exceeded the Maximum Contamination Level for drinking water. Dallas Water Utilities collected pesticide samples during a storm in February 1977. Samples were collected at 17 sites with detections of some pesticides in over 50 percent of the samples. Diazinon was detected in 56 percent of samples and 2,4–D was found in 56 percent of samples. Texas Parks and Wildlife Department collected samples from fish tissue for analyses of organochlorine pesticides from 15 sites in the Dallas-Fort Worth area. Chlordane concentrations in some of the samples exceeded the Food and Drug Administration’s action level of 300 micrograms per kilogram. The Texas Water Commission collected ground-water samples in the study area during 1990 for the major types of pesticides and none were detected. No arsenic was detected in samples from 121 wells in or near the study area. Organochlorine and organophosphate samples were collected beginning in 1974 and ending in 1991. Concentrations of organochlorine pesticides in bed sediment decrease with increasing distance downstream from the Dallas-Fort Worth urban area. Pesticide samples collected by the U.S. Geological Survey indicated significant rank correlation between number of detects of chlordane and the percent of the contributing watershed classified as urban land use. Dieldrin in bed sediment samples, and lindane, diazinon, and malathion, in water samples, also were significantly correlated with urban land use. Chlordane and dieldrin were significantly correlated with distance downstream from the Dallas-Fort Worth urban area. Review of all available data showed that pesticides were detected to a substantial degree in various sample media over the time period covered by this report. The authors were able to locate little pesticide-sample data for ground water or for tributary streams because sampling efforts historically have been concentrated on the mainstem Trinity River.
This report summarizes a preliminary study of bed-material transport, vertical and lateral channel changes, and existing datasets for the Coquille River basin, which encompasses 2,745 km 2 (square kilometers) of the southwestern Oregon coast. This study, conducted to inform permitting decisions regarding instream gravel mining, revealed that: The 115.4-km-long study area on the South Fork and mainstem Coquille River can be divided into four reaches on the basis of topography and hydrology. In the fluvial (nontidal, or dominated by riverine processes) reaches on the South Fork Coquille River, the channel consists of bedrock and alluvium in the Powers Reach and mostly alluvium in the Broadbent Reach. In both fluvial reaches, the channel alternates between confined and unconfined segments and contains gravel bars. In the tidally affected Myrtle Point and Bandon Reaches, the channel consists of alluvial deposits and contains sparse gravel and sand bars as well as expansive mud flats and tidal marshes near the Coquille River mouth. The 15.4- and 14.6-km-long study areas on the Middle and North Forks of the Coquille River, respectively, were treated as distinct reaches. The channel beds consist of mixed bedrock and alluvium in the Bridge Reach on the Middle Fork Coquille River and alluvium in the Gravelford Reach on the North Fork Coquille River. Both of these reaches contain fewer bars than the Powers and Broadbent Reaches on the South Fork Coquille River and are predominately fluvial. Channel condition, bed-material transport, and the distribution and area of bars have likely been influenced by logging and splash damming, dredging and wood removal for navigation, historical and ongoing instream gravel mining, gold mining, fires, and mass movements. These anthropogenic and natural disturbances likely have varying effects on channel condition and sediment flux throughout the study area and over time. Available data include at least eight sets of aerial and orthophotographs that were taken of the study area from 1939 to 2011 that are available for assessing long-term changes in channel condition, bar area, and vegetation establishment patterns. Additionally, a high-resolution Light Detection And Ranging (LiDAR) survey conducted in 2008 for nearly the entire study area would be useful in future quantitative analyses of channel morphology and bed-material transport. Previous studies found (1) substantial bank erosion in the Broadbent Reach, resulting in banks with near vertical profiles and heights exceeding 7.6 m, (2) erosion of over 40,000 square meters of riparian land from 1939 to 1992, (3) incision along the South Fork Coquille River, and (4) potential for lateral channel migration at several locations along the mainstem and South Fork Coquille River. A review of deposited and mined bed-material estimates derived largely from repeat surveys at instream mining sites on the South Fork Coquille River indicates that bed material transported by the river tends to rebuild mined bar surfaces in most years. Reported annual deposition volumes for 1996–2009 indicate average transport of over 34,700 cubic meters per year (m 3 /yr) of bed material into the South Fork Coquille River study area. The spatial variation in the number and area of gravel bars is controlled by factors such as valley confinement, channel slope, basin geology, and tidal extent. The Powers and Broadbent Reaches of the South Fork Coquille River have the greatest abundance of gravel bars, likely owing to a substantial area of the South Fork Coquille River basin draining the gravel-producing Klamath Mountains geologic province. From 1939 to 2009, the fluvial reaches all had a net loss in bar area, ranging from 24 percent in the Powers Reach to 56 percent in the Bridge Reach. In the Powers and Broadbent Reaches, the declines in active bar area were associated primarily with vegetation establishment on bar surfaces and lateral bar erosion. The reductions in active bar area were attributed to vegetation establishment in the Bridge and Gravelford Reaches as well as some lateral bar erosion in the Bridge Reach. In contrast, the tidal Myrtle Point and Bandon Reaches had a net increase in bar area (28 and 29 percent, respectively) from 1939 to 2009. In the Myrtle Point Reach, these increases in bar area were primarily attributed to lateral channel migration that led to the deposition of bed material at newly formed bars. In the Bandon Reach, bar area increased primarily in the lower 5.4 km of the reach owing possibly to factors such as tide differences between the photographs and sediment deposition. Analyses of multiple channel cross sections along the South Fork Coquille River as well as historical stage-discharge data collected by the U.S. Geological Survey (USGS) at Powers, Oregon, indicate that the bed of the South Fork Coquille River has locally lowered, as much as 1.9 m from 1994 to 2008 for one site in the Broadbent Reach. Stage-discharge data indicate persistent incision at the Powers site since 1939 (with a net incision of about 0.3 m) that has been interrupted by episodic aggradation apparently corresponding with large floods. For the Bridge and Gravelford Reaches on the Middle and North Forks of the Coquille River, channel cross sections indicate a mix of aggradation and incision as well as bank erosion and deposition from 1992 to 2010 and 2000 to 2009, respectively. Cross sections in the tidal reaches indicate local incision of 0.4 m in at one site in the Myrtle Point Reach from 2004 to 2008 and 0.5 m at one site in in the Bandon Reach from 2000 to 2010. On the South Fork Coquille River, the median diameter of surface particles varied from 78.0 mm (millimeters) at China Flat Bar slightly upstream of the study area to 48.8 mm at Seals Bar in the Broadbent Reach. The armoring ratio (or ratio of the median grain sizes of the surface and subsurface layers) for Seals Bar was 3.5, indicating that the river’s transport capacity likely exceeds sediment supply at this site. Most fluvial reaches in the Coquille River study area are likely supply-limited, meaning that the river’s transport capacity exceeds the supply of bed-material, as indicated by the intermittent bedrock outcrops in the Powers and Bridge Reaches and the paucity of bars in the Bridge and Gravelford Reaches. The Broadbent Reach of the South Fork Coquille River may be presently and probably was historically transport-limited, meaning that bed-material transport is primarily a function of local transport capacity. However, the locally coarse bed texture, high armoring ratio measured at Seals Bar, and recent channel incision indicate that sediment supply has likely diminished relative to transport capacity in recent decades. Because of exceedingly low gradients, the tidal Myrtle Point and Bandon Reaches are transport limited. Bed material in these reaches is primarily sand and finer grain-size material, much of which is probably transported as suspended load from upstream reaches. The tidal reaches will be most susceptible to watershed conditions affecting the supply and transport of fine sediment. Compared to the nearby Chetco and Rogue Rivers and Hunter Creek on the southwestern Oregon coast, the Coquille River likely has lower overall transport of gravel bed material. While the conclusion of lower bed-material transport in the Coquille River is tentative in the absence of actual transport measurements or transport capacity calculations, empirical evidence including the much lower area and frequency of bars for most of the Coquille River study area and the head of tide reaching to RKM (river kilometer) 63.2 on the South Fork Coquille River supports this conclusion. More detailed investigations of bed-material transport rates and channel morphology would support assessments of lateral and vertical channel condition and longitudinal trends in bed material. Such assessments would be most practical for the Powers and Broadbent Reaches and relevant to several ongoing management and ecological issues pertaining to sand and gravel transport. The tidal Bandon and Myrtle Point Reaches may also be logical subjects for in-depth analyses of fine sediment deposition and transport (and associated channel and riparian conditions and processes) rather than coarse bed material.
General stream measurement work looking toward a comprehensive inventory of the water resources of the state has been continued during the biennium by the United States Geological Survey under the usual cooperative agreement with the State Engineer. Since 1909 Utah in company with many other states has made regular legislative appropriations for the purpose of assisting and hastening the determination of the water supply of the United States by the Geographical Survey. Because of the comparatively small Federal appropriations the scope of this wok in the individual states has been largely influenced by the amount of the state cooperation. The funds contributed by each state have all been expended within that state and matched as far as possible by funds of the Geographical Survey. Up to the present, however, the Federal funds have been insufficient to match the state contributions beyond a very limited amount and in many localities the large amount of work done has been made possible only by correspondingly large unmatched state appropriations. During this period the regular stream gaging work in Utah has been practically limited to that possible with approximately ten thousand dollars annually divided about equally between the state and Geological Survey with the government’s share including the cost at Washington of general supervision, and the review, editing, and publication of the records. This has been the maximum amount that it has been possible to allot any one state to meet state cooperation.
In environmental participatory modeling (PM), both computer and non-computer-based modeling techniques are used to aid participatory problem description, solution, and decision-making actions in environmental contexts. Although many PM case studies have been published, few efforts have sought to systematically describe and understand dominant PM processes or establish best practices for PM. As a first step, we have reviewed a random sample of environmental PM case study articles (n = 60) using a novel PM process evaluation instrument. We found that significant work likely remains for PM to fully support participatory and integrated planning processes. While PM reports systematically address knowledge integration and learning, they often neglect the facilitation of a multi-value perspective within a democratic process , and the integration across organizations within a governance system. If not reported, we suspect these aspects are also neglected in practice. We conclude with key research and practice issues for improving PM as an approach for real-world participatory planning and governance.
The glacial anticyclone theory, which William H. Hobbs propounded in 1910, is today still the only definitely formulated theory concerning the atmospheric movements that take place over an ice sheet of large extent. It stands chiefly on deductive grounds and contains several features that to climatologists as well as to glaciologists have always seemed questionable. Aside from the need of its verification for scientific reasons, there is now also urgent practical need for reliable information about the weather conditions that prevail over the ice sheet of Greenland, for Greenland lies athwart several of the great air routes of the future. In this paper, accordingly, the glacial anticyclone theory is first analyzed and then confronted with the facts of observation that are now at hand, especially those reported from the fixed meteorological stations which were maintained in the interior of Greenland during the 1930s. In this, the first part of the paper, the meteorological data from the Eismitte station of the German Wegener Expedition are reviewed. The second part will cover the areological data of that expedition and the similar material from the other ice‐cap stations. The conclusions reached are that there is no evidence of a virtually permanent “glacial anticyclone” centered over the Greenland ice sheet. On the contrary, there is consistent evidence from all parts of Greenland that the weather over the ice sheet is controlled by alternating cyclonic and anticyclonic movements. Cyclonic activity is most intense in southern Greenland and weakest in northern Greenland. The entire ice sheet is supplied with snow brought by rising maritime air masses, not by air descending from the upper troposphere. Aviators need not expect so much as a fifty‐fifty chance of meeting with good weather on flights across central Greenland, except for a few weeks in midsummer.
Review of: A Review and Synthesis of Effects of Alterations to the Water Temperature Regime on Freshwater Life Stages of Salmonids, with Special Reference to Chinook Salmon. By Dale A. McCullough. Columbia River Inter-Tribal Fish Commission. 22 February 1999. REPORT #: EPA 910-R-99-010.
The African continent contains approximately 5 percent of the world's proven recoverable reserves of coal (World Energy Council, 2007). Energy consumption in Africa is projected to grow at an annual rate of 2.3 percent from 2004 through 2030, while average consumption in first-world nations is expected to rise at 1.4 percent annually (Energy Information Administration, 2007). Coal reserves will undoubtedly continue to be part of Africa's energy portfolio as it grows in the future. A review of academic and industrial literature indicates that 27 nations in Africa contain coal-bearing rock. South Africa accounts for 96 percent of Africa's total proven recoverable coal reserves, ranking it sixth in the world. This report is a digital compilation of information on Africa's coal-bearing geology found in the literature and is intended to be used in small scale spatial investigations in a Geographic Information System (GIS) and as a visual aid for the discussion of Africa's coal resources. Many maps of African coal resources often include points for mine locations or regional scale polygons with generalized borders depicting basin edges. Point locations are detailed but provide no information regarding extent, and generalized polygons do not have sufficient detail. In this dataset, the polygons are representative of the actual coal-bearing lithology both in location and regional extent. Existing U.S. Geological Survey (USGS) digital geology datasets provide the majority of the base geologic polygons. Polygons for the coal-bearing localities were clipped from the base geology that represented the age and extent of the coal deposit as indicated in the literature. Where the 1:5,000,000-scale geology base layer's ages conflicted with those in the publications, polygons were generated directly from the regional African coal maps (1:500,000 scale, approximately) in the published material. In these cases, coal-bearing polygons were clipped to the literature's indicated coal extent, without regard to the underlying geology base or topographic constraints. Indication of the presence of African coal is based on multiple sources. However, the quality of the sources varies and there is often disagreement in the literature. This dataset includes the rank, age, and location of coal in Africa as well as the detailed source information responsible for each coal-bearing polygon. The dataset is not appropriate for use in resource assessments of any kind. Attributes necessary for tasks, such as number of coal seams, thickness of seams, and depth to coal are rarely provided in the literature and accordingly not represented in this data set. Small-scale investigations, representations and display uses are most appropriate for this product. This product is the first to show coal distribution as bounded by actual geologic contacts for the entire African continent. In addition to the spatial component of this dataset, complete references to source material are provided for each polygon, making this product a useful first step resource in African coal research. Greater detail regarding the creation of this dataset as well as the sources used is provided in the metadata file for the Africa_coal.shp file.
Chronic wasting disease (CWD) is a major concern for the management of North American cervid populations. This fatal prion disease has led to declines in populations which have high CWD prevalence and areas with both high and low infection rates have experienced economic losses in wildlife recreation and fears of potential spill-over into livestock or humans. Research from human and veterinary medicine has established that the prion protein gene ( Prnp ) encodes the protein responsible for transmissible spongiform encephalopathies (TSEs). Polymorphisms in the Prnp gene can lead to different prion forms that moderate individual susceptibility to and progression of TSE infection. Prnp genes have been sequenced in a number of cervid species including those currently infected by CWD (elk, mule deer, white-tailed deer, moose) and those for which susceptibility is not yet determined (caribou, fallow deer, sika deer). Over thousands of sequences examined, the Prnp gene is remarkably conserved within the family Cervidae; only 16 amino acid polymorphisms have been reported within the 256 amino acid open reading frame in the third exon of the Prnp gene. Some of these polymorphisms have been associated with lower rates of CWD infection and slower progression of clinical CWD. Here we review the body of research on Prnp genetics of North American cervids. Specifically, we focus on known polymorphisms in the Prnp gene, observed genotypic differences in CWD infection rates and clinical progression, mechanisms for genetic TSE resistance related to both the cervid host and the prion agent and potential for natural selection for CWD-resistance. We also identify gaps in our knowledge that require future research.
The U.S. Geological Survey has monitored the quality and quantity of streamflow at the Rocky Mountain Arsenal (RMA) northeast of Denver, Colorado, since the early 1990s in cooperation with the U.S. Army. This report, prepared in cooperation with the U.S. Fish and Wildlife Service, documents existing surface-water-quality conditions on the RMA. All RMA water-quality data for the Irondale Gulch and First Creek Basins adjacent to and on the RMA were reviewed. Where applicable, water-quality data were compared to State standards established by the Colorado Department of Public Health and Environment. At both the Havana Interceptor below 56th Avenue gaging station and the Uvalda Interceptor below 56th Avenue gaging station, all of the dissolved-oxygen concentrations met the State standard requiring at least 5.0 milligrams per liter (mg/L) of dissolved oxygen for the protection of aquatic life. In contrast, the dissolved-oxygen concentrations at the Peoria Interceptor below 56th Avenue gage commonly were less than 5.0 mg/L. Excluding one suspect concentration of 1.6 mg/L, the dissolved-oxygen concentrations for the First Creek Basin ranged from 4.2 to 12.6 mg/L. Excluding the one suspect value, three dissolved-oxygen concentrations failed to meet the State standard of 5.0 mg/L at the First Creek below Buckley Road site. At the Peoria Interceptor below 56th Avenue site, all pH values were within the range specified by the State standard (6.50-8.99). Results of seven sampling events at the Havana Interceptor below 56th Avenue gaging station indicated a pH greater than or equal to 9 (pH values of 9 or greater exceed the upper limit of the standard). No sampling events indicated a pH less than 6.50. Results from one sampling event at the Uvalda Interceptor below 56th Avenue indicated pH values outside the range specified by the State standard. The concentrations obtained for chloride, magnesium, and sodium generally were below 200 mg/L at all three Irondale Gulch monitoring stations for the entire period of record, but there were a few sampling events at each of these sites where much higher concentrations for these analytes were obtained. The median concentrations for calcium, magnesium, and sodium generally were higher at the First Creek below Buckley Road site than in the three Irondale Gulch sites, while the 90th percentile and maximum concentrations for magnesium and sodium generally were higher at the three Irondale Gulch sites than at the First Creek below Buckley Road site. The urban runoff flowing onto the RMA had low concentrations and few, if any, detections for most organic contaminants. Part of the reason for low detections of organic contaminants may be in how the samples are collected. The existing surface-water sampling program was not designed specifically to target storm runoff and therefore does not characterize water quality for all hydrologic regimes, most notably storm runoff. As a result, the existing data may not adequately represent potential contaminant transport onto the RMA. In addition, during stormwater-runoff events, the sites examined for this report frequently are subject to sharp increases in discharge, and just as quickly the discharge rapidly recedes. These types of transient flow events make water-quality sampling difficult, and none of the sites have a safe place to sample the higher flows that occur in any given year. As a result, most of the surface-water-quality samples were collected after the flow had decreased substantially from the peak flow, which may have transported much of the chemical contaminant load through the system. Thus, little is known about the water quality during the critical initial stormwater-runoff period when contaminants are most likely to be mobilized and transported through the stormwater conveyances past the locations where gaging stations are located.
The U.S. Geological Survey’s PAGER automated alert system provides rapid (10-20 min) loss estimates in terms of ranges of fatalities and economic impact for all significant earthquakes around the globe. In contrast, FEMA’s Hazus software, which is currently operated manually by FEMA personnel internally within several hours of any large domestic earthquake, provides more detailed loss information quantified in terms of physical damage to the building stock, as well as a broad range of social and economic consequences estimated at a much higher spatial resolution (census-tract level). Hazus was originally designed for FEMA’s mitigation planning, but has been used of late for post-earthquake situational awareness. While the quick alerts generated automatically by the PAGER system are a suitable way to initially identify consequences for earthquakes, there remains a need to provide detailed loss information for facilitating a wider array of post-earthquake decisions among emergency managers. As such, we have developed a prototype summary product that takes advantage of the benefits of both these loss models for significant domestic earthquakes. The signature product, a new twoPAGER report, will serve as a supplement to the widely deployed standard onePAGER product for all significant domestic earthquakes. Page one is the standard, automated PAGER alert content, with summary alert levels for overall fatality and economic loss estimates, as well as summary content on recent earthquakes, structure vulnerability, and historical secondary hazards. As soon as the Hazus run using the most up-to-date version of the USGS ShakeMap is completed and reviewed by both agencies, the second alert page will be generated and delivered via the USGS website as an update. This second page will contain a summary of the more comprehensive Hazus model results, including spatially distributed estimates of: affected population, economic impact, non-fatal injuries, displaced households, and damage to structures (including potential building safety evaluation requirements). This enhancement does not affect the timeliness and the importance of the initial (onePAGER) alerting content for significant earthquakes; however, the twoPAGER report will provide more detailed, damage and loss/impact content for the Nation in the critical hours following a damaging earthquake.