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Sample records for river region alaska

  1. Effects of recent volcanic eruptions on aquatic habitat in the Drift River, Alaska, USA: Implications at other Cook Inlet region volcanoes

    Science.gov (United States)

    Dorava, J.M.; Milner, A.M.

    1999-01-01

    Numerous drainages supporting productive salmon habitat are surrounded by active volcanoes on the west side of Cook Inlet in south-central Alaska. Eruptions have caused massive quantities of flowing water and sediment to enter the river channels emanating from glaciers and snowfields on these volcanoes. Extensive damage to riparian and aquatic habitat has commonly resulted, and benthic macroinvertebrate and salmonid communities can be affected. Because of the economic importance of Alaska's fisheries, detrimental effects on salmonid habitat can have significant economic implications. The Drift River drains glaciers on the northern and eastern flanks of Redoubt Volcano: During and following eruptions in 1989-1990, severe physical disturbances to the habitat features of the river adversely affected the fishery. Frequent eruptions at other Cook Inlet region volcanoes exemplify the potential effects of volcanic activity on Alaska's important commercial, sport, and subsistence fisheries. Few studies have documented the recovery of aquatic habitat following volcanic eruptions. The eruptions of Redoubt Volcano in 1989-1990 offered an opportunity to examine the recovery of the macroinvertebrate community. Macroinvertebrate community composition and structure in the Drift River were similar in both undisturbed and recently disturbed sites. Additionally, macroinvertebrate samples from sites in nearby undisturbed streams were highly similar to those from some Drift River sites. This similarity and the agreement between the Drift River macroinvertebrate community composition and that predicted by a qualitative model of typical macroinvertebrate communities in glacier-fed rivers indicate that the Drift River macroinvertebrate community is recovering five years after the disturbances associated with the most recent eruptions of Redoubt Volcano.

  2. RESEARCH: Effects of Recent Volcanic Eruptions on Aquatic Habitat in the Drift River, Alaska, USA: Implications at Other Cook Inlet Region Volcanoes.

    Science.gov (United States)

    DORAVA; MILNER

    1999-02-01

    / Numerous drainages supporting productive salmon habitat are surrounded by active volcanoes on the west side of Cook Inlet in south-central Alaska. Eruptions have caused massive quantities of flowing water and sediment to enter the river channels emanating from glaciers and snowfields on these volcanoes. Extensive damage to riparian and aquatic habitat has commonly resulted, and benthic macroinvertebrate and salmonid communities can be affected. Because of the economic importance of Alaska's fisheries, detrimental effects on salmonid habitat can have significant economic implications. The Drift River drains glaciers on the northern and eastern flanks of Redoubt Volcano. During and following eruptions in 1989-1990, severe physical disturbances to the habitat features of the river adversely affected the fishery. Frequent eruptions at other Cook Inlet region volcanoes exemplify the potential effects of volcanic activity on Alaska's important commercial, sport, and subsistence fisheries. Few studies have documented the recovery of aquatic habitat following volcanic eruptions. The eruptions of Redoubt Volcano in 1989-1990 offered an opportunity to examine the recovery of the macroinvertebrate community. Macroinvertebrate community composition and structure in the Drift River were similar in both undisturbed and recently disturbed sites. Additionally, macroinvertebrate samples from sites in nearby undisturbed streams were highly similar to those from some Drift River sites. This similarity and the agreement between the Drift River macroinvertebrate community composition and that predicted by a qualitative model of typical macroinvertebrate communities in glacier-fed rivers indicate that the Drift River macroinvertebrate community is recovering five years after the disturbances associated with the most recent eruptions of Redoubt Volcano. KEY WORDS: Aquatic habitat; Volcanoes; Lahars; Lahar-runout flows; Macroinvertebrates; Community structure; Community composition

  3. Geomorphology and river dynamics of the lower Copper River, Alaska

    Science.gov (United States)

    Brabets, Timothy P.; Conaway, Jeffrey S.

    2009-01-01

    Located in south-central Alaska, the Copper River drains an area of more than 24,000 square miles. The average annual flow of the river near its mouth is 63,600 cubic feet per second, but is highly variable between winter and summer. In the winter, flow averages approximately 11,700 cubic feet per second, and in the summer, due to snowmelt, rainfall, and glacial melt, flow averages approximately 113,000 cubic feet per second, an order of magnitude higher. About 15 miles upstream of its mouth, the Copper River flows past the face of Childs Glacier and enters a large, broad, delta. The Copper River Highway traverses this flood plain, and in 2008, 11 bridges were located along this section of the highway. The bridges cross several parts of the Copper River and in recent years, the changing course of the river has seriously damaged some of the bridges.Analysis of aerial photography from 1991, 1996, 2002, 2006, and 2007 indicates the eastward migration of a channel of the Copper River that has resulted in damage to the Copper River Highway near Mile 43.5. Migration of another channel in the flood plain has resulted in damage to the approach of Bridge 339. As a verification of channel change, flow measurements were made at bridges along the Copper River Highway in 2005–07. Analysis of the flow measurements indicate that the total flow of the Copper River has shifted from approximately 50 percent passing through the bridges at Mile 27, near the western edge of the flood plain, and 50 percent passing through the bridges at Mile 36–37 to approximately 5 percent passing through the bridges at Mile 27 and 95 percent through the bridges at Mile 36–37 during average flow periods.The U.S. Geological Survey’s Multi-Dimensional Surface-Water Modeling System was used to simulate water-surface elevation and velocity, and to compute bed shear stress at two areas where the Copper River is affecting the Copper River Highway. After calibration, the model was used to examine the

  4. 77 FR 4579 - Alaska Region's Subsistence Resource Commission (SRC) Program

    Science.gov (United States)

    2012-01-30

    ... DEPARTMENT OF THE INTERIOR National Park Service [NPS-AKR-DENA; 9924-PYS] Alaska Region's... public meeting for the National Park Service (NPS) Alaska Region's Subsistence Resource Commission (SRC..., Associate Regional Director, Resources and Subsistence, Alaska Region. [FR Doc. 2012-1877 Filed 1-27-12; 8...

  5. 77 FR 4581 - Alaska Region's Subsistence Resource Commission (SRC) Program

    Science.gov (United States)

    2012-01-30

    ... DEPARTMENT OF THE INTERIOR National Park Service [NPS-AKR-LACL; 9924-PYS] Alaska Region's... public meeting for the National Park Service (NPS) Alaska Region's Subsistence Resource Commission (SRC... Meeting Debora R. Cooper, Associate Regional Director, Resources and Subsistence, Alaska Region. [FR Doc...

  6. 77 FR 4578 - Alaska Region's Subsistence Resource Commission (SRC) Program

    Science.gov (United States)

    2012-01-30

    ... DEPARTMENT OF THE INTERIOR National Park Service [NPS-AKR-ANIA; 9924-PYS] Alaska Region's... public meeting for the National Park Service (NPS) Alaska Region's Subsistence Resource Commission (SRC..., Alaska Region. [FR Doc. 2012-1860 Filed 1-27-12; 8:45 am] BILLING CODE 4310-HE-P ...

  7. Alligator Rivers Region

    International Nuclear Information System (INIS)

    1992-01-01

    An introduction to the Alligator Rivers Region is presented. It contains general information regarding the physiography, climate, hydrology and mining of the region. The Alligator Rivers Region is within an ancient basin, the Pine Creek Geosyncline, which has an area of approximately 66000 km 2 . The Geosyncline has a history of mineral exploitation dating back to 1865, during which time 16 metals have been extracted (silver, arsenic, gold, bismuth, cadmium, cobalt, copper, iron, manganese, molybdenum, lead, tin, tantalum, uranium, tungsten, zinc). Uranium exploration in the Pine Creek Geosyncline was stimulated by the discovery in 1949 of secondary uranium mineralisation near Rum June, 70 km south-east of Darwin. This was followed by a decade of intense exploration activity resulting in the discoveries of economic uranium ore bodies at Rum Jungle and in the upper reaches of the South Alligator River Valley. All the known major uranium deposits of the East Alligator River uranium field have been discovered since 1969. The present known resources of the Geosyncline are approximately 360 000 tonnes of contained U 3 O 8 . 2 refs., 2 figs., 1 tab

  8. Remediating and Monitoring White Phosphorus Contamination at Eagle River Flats (Operable Unit C), Fort Richardson, Alaska

    National Research Council Canada - National Science Library

    Walsh, M. E; Racine, C. H; Collins, C. M; Walsh, M. R; Bailey, R. N

    2001-01-01

    .... Army Engineer District, Alaska, and U.S. Army Alaska, Public Works, describing the results of research, monitoring, and remediation efforts addressing the white phosphorus contamination in Eagle River Flats, an 865-ha estuarine salt marsh...

  9. Satellite Sounder Data Assimilation for Improving Alaska Region Weather Forecast

    Science.gov (United States)

    Zhu, Jiang; Stevens, E.; Zavodsky, B. T.; Zhang, X.; Heinrichs, T.; Broderson, D.

    2014-01-01

    Data assimilation has been demonstrated very useful in improving both global and regional numerical weather prediction. Alaska has very coarser surface observation sites. On the other hand, it gets much more satellite overpass than lower 48 states. How to utilize satellite data to improve numerical prediction is one of hot topics among weather forecast community in Alaska. The Geographic Information Network of Alaska (GINA) at University of Alaska is conducting study on satellite data assimilation for WRF model. AIRS/CRIS sounder profile data are used to assimilate the initial condition for the customized regional WRF model (GINA-WRF model). Normalized standard deviation, RMSE, and correlation statistic analysis methods are applied to analyze one case of 48 hours forecasts and one month of 24-hour forecasts in order to evaluate the improvement of regional numerical model from Data assimilation. The final goal of the research is to provide improved real-time short-time forecast for Alaska regions.

  10. Southwest Alaska Regional Geothermal Energy Project

    Energy Technology Data Exchange (ETDEWEB)

    Holdmann, Gwen [Univ. of Alaska, Fairbanks, AK (United States)

    2015-04-30

    The village of Elim, Alaska is 96 miles west of Nome, on the Seward Peninsula. The Darby Mountains north of the village are rich with hydrothermal systems associated with the Darby granitic pluton(s). In addition to the hot springs that have been recorded and studied over the last 100 years, additional hot springs exist. They are known through a rich oral history of the region, though they are not labeled on geothermal maps. This research primarily focused on Kwiniuk Hot Springs, Clear Creek Hot Springs and Molly’s Hot Springs. The highest recorded surface temperatures of these resources exist at Clear Creek Hot Springs (67°C). Repeated water sampling of the resources shows that maximum temperatures at all of the systems are below boiling.

  11. Monitoring winter flow conditions on the Ivishak River, Alaska : final report.

    Science.gov (United States)

    2017-09-01

    The Sagavanirktok River, a braided river on the Alaska North Slope, flows adjacent to the trans-Alaska pipeline for approximately 100 miles south of Prudhoe Bay. During an unprecedented flooding event in mid-May 2015, the pipeline was exposed in an a...

  12. Glaciers along proposed routes extending the Copper River Highway, Alaska

    Science.gov (United States)

    Glass, R.L.

    1996-01-01

    Three inland highway routes are being considered by the Alaska Department of Transportation and Public Facilities to connect the community of Cordova in southcentral Alaska to a statewide road system. The routes use part of a Copper River and Northwest Railway alignment along the Copper River through mountainous terrain having numerous glaciers. An advance of any of several glaciers could block and destroy the roadway, whereas retreating glaciers expose large quantities of unconsolidated, unvegetated, and commonly ice-rich sediments. The purpose of this study was to map historical locations of glacier termini near these routes and to describe hazards associated with glaciers and seasonal snow. Historical and recent locations of glacier termini along the proposed Copper River Highway routes were determined by reviewing reports and maps and by interpreting aerial photographs. The termini of Childs, Grinnell, Tasnuna, and Woodworth Glaciers were 1 mile or less from a proposed route in the most recently available aerial photography (1978-91); the termini of Allen, Heney, and Schwan Glaciers were 1.5 miles or less from a proposed route. In general, since 1911, most glaciers have slowly retreated, but many glaciers have had occasional advances. Deserted Glacier and one of its tributary glaciers have surge-type medial moraines, indicating potential rapid advances. The terminus of Deserted Glacier was about 2.1 miles from a proposed route in 1978, but showed no evidence of surging. Snow and rock avalanches and snowdrifts are common along the proposed routes and will periodically obstruct the roadway. Floods from ice-dammed lakes also pose a threat. For example, Van Cleve Lake, adjacent to Miles Glacier, is as large as 4.4 square miles and empties about every 6 years. Floods from drainages of Van Cleve Lake have caused the Copper River to rise on the order of 20 feet at Million Dollar Bridge.

  13. Mapping Soil Carbon in the Yukon Kuskokwim River Delta Alaska

    Science.gov (United States)

    Natali, S.; Fiske, G.; Schade, J. D.; Mann, P. J.; Holmes, R. M.; Ludwig, S.; Melton, S.; Sae-lim, N.; Jardine, L. E.; Navarro-Perez, E.

    2017-12-01

    Arctic river deltas are hotspots for carbon storage, occupying 10% of carbon stored in arctic permafrost. The Yukon Kuskokwim (YK) Delta, Alaska is located in the lower latitudinal range of the northern permafrost region in an area of relatively warm permafrost that is particularly vulnerable to warming climate. Active layer depths range from 50 cm on peat plateaus to >100 cm in wetland and aquatic ecosystems. The size of the soil organic carbon pool and vulnerability of the carbon in the YK Delta is a major unknown and is critically important as climate warming and increasing fire frequency may make this carbon vulnerable to transport to aquatic and marine systems and the atmosphere. To characterize the size and distribution of soil carbon pools in the YK Delta, we mapped the land cover of a 1910 km2 watershed located in a region of the YK Delta that was impacted by fire in 2015. The map product was the result of an unsupervised classification using the Weka K Means clustering algorithm implemented in Google's Earth Engine. Inputs to the classification were Worldview2 resolution optical imagery (1m), Arctic DEM (5m), and Sentinel 2 level 1C multispectral imagery, including NDVI, (10 m). We collected 100 soil cores (0-30 cm) from sites of different land cover and landscape position, including moist and dry peat plateaus, high and low intensity burned plateaus, fens, and drained lakes; 13 lake sediment cores (0-50 cm); and 20 surface permafrost cores (to 100 cm) from burned and unburned peat plateaus. Active layer and permafrost soils were analyzed for organic matter content, soil moisture content, and carbon and nitrogen pools (30 and 100 cm). Soil carbon content varied across the landscape; average carbon content values for lake sediments were 12% (5- 17% range), fens 26% (9-44%), unburned peat plateaus 41% (34-44%), burned peat plateaus 19% (7-34%). These values will be used to estimate soil carbon pools, which will be applied to the spatial extent of each

  14. Investigation of Alaska's uranium potential. Part 1. Reconnaissance program, West-Central Alaska and Copper River basin. Part 2. Uranium and thorium in granitic and alkaline rocks in Western Alaska

    International Nuclear Information System (INIS)

    Eakins, G.R.; Jones, B.K.; Forbes, R.B.

    1977-02-01

    A 6-week reconnaissance program was conducted in west-central Alaska and in the Copper River basin--Chitina River valley area to aid in determining the uranium potential of the state. Division personnel also submitted samples from the Healy, Eagle, and Charley River quadrangles. Collected were 916 stream-sediment samples and 427 bedrock samples for uranium, thorium, and potassium oxide determinations, and 565 water samples for uranium analyses. A statistical analysis of the determinations was made using a computer at the University of Alaska. Thresholds, anomalies, and U:Th ratios were calculated for eight separate regions. Anomalous values of the U, Th, and K 2 O, and radiometric measurements are discussed. A combination of all uranium exploration techniques is needed to locate potential uranium deposits in Alaska. Correlations between aerial and ground radiometric surveys and geochemical surveys were often lacking, indicating that each method may or may not be effective, depending on local conditions. One hundred and eight rock samples were selected from traverses across five plutons in western Alaska and analyzed for uranium, thorium, and potassium. The highest uranium concentrations detected were 86 and 92 ppM from a mineralized dike intrusion zone in the Selawik Lake Complex. Analysis of individual plutons yields strong correlations between mineralogy and radioactivity. The mineralogical variable that correlates with uranium or thorium varies from one pluton to the next. Based on these correlations, mineralogical guidelines are offered for the selection of uranium enriched variants in four of the five plutons

  15. Regional biomass stores and dynamics in forests of coastal Alaska

    Science.gov (United States)

    Mikhaill A. Yatskov; Mark E. Harmon; Olga N. Krankina; Tara M. Barrett; Kevin R. Dobelbower; Andrew N. Gray; Becky Fasth; Lori Trummer; Toni L. Hoyman; Chana M. Dudoit

    2015-01-01

    Coastal Alaska is a vast forested region (6.2 million ha) with the potential to store large amounts of carbon in live and dead biomass thus influencing continental and global carbon dynamics. The main objectives of this study were to assess regional biomass stores, examine the biomass partitioning between live and dead pools, and evaluate the effect of disturbance on...

  16. Southwest Alaska Regional Geothermal Energy Projec

    Energy Technology Data Exchange (ETDEWEB)

    Holdmann, Gwen [Univ. of Alaska, Fairbanks, AK (United States)

    2015-04-30

    Drilling and temperature logging campaigns between the late 1970's and early 1980’s measured temperatures at Pilgrim Hot Springs in excess of 90°C. Between 2010 and 2014 the University of Alaska used a variety of methods including geophysical surveys, remote sensing techniques, heat budget modeling, and additional drilling to better understand the resource and estimate the available geothermal energy.

  17. Indigenous observations of climate change in the Lower Yukon River Basin, Alaska

    Science.gov (United States)

    Herman-Mercer, Nicole M.; Schuster, Paul F.; Maracle, Karonhiakt'tie

    2011-01-01

    Natural science climate change studies have led to an overwhelming amount of evidence that the Arctic and Subarctic are among the world's first locations to begin experiencing climate change. Indigenous knowledge of northern regions is a valuable resource to assess the effects of climate change on the people and the landscape. Most studies, however, have focused on coastal Arctic and Subarctic communities with relatively little focus on inland communities. This paper relates the findings from fieldwork conducted in the Lower Yukon River Basin of Alaska in the spring of 2009. Semi-structured interviews were conducted with hunters and elders in the villages of St. Mary's and Pitka's Point, Alaska to document observations of climate change. This study assumes that scientific findings and indigenous knowledge are complementary and seeks to overcome the false dichotomy that these two ways of knowing are in opposition. The observed changes in the climate communicated by the hunters and elders of St. Mary's and Pitka's Point, Alaska are impacting the community in ways ranging from subsistence (shifting flora and fauna patterns), concerns about safety (unpredictable weather patterns and dangerous ice conditions), and a changing resource base (increased reliance on fossil fuels). Here we attempt to address the challenges of integrating these two ways of knowing while relating indigenous observations as described by elders and hunters of the study area to those described by scientific literature.

  18. 76 FR 41763 - Proposed Information Collection; Comment Request; Alaska Region Logbook Family of Forms

    Science.gov (United States)

    2011-07-15

    ... Collection; Comment Request; Alaska Region Logbook Family of Forms AGENCY: National Oceanic and Atmospheric... (NMFS) Alaska Region manages the United States (U.S.) groundfish fisheries of the Exclusive Economic.... NMFS Alaska Region requests information from participating groundfish participants. This information...

  19. Chena River Lakes Project, Fairbanks, Alaska. Overview of Tanana River Monitoring Research Studies Near Fairbanks, Alaska.

    Science.gov (United States)

    1984-01-01

    SOILS The regional soil association along both reaches is loamy, consisting of nearly level histic pergelic cryaquepts5 and typic cryofluvents6...are flooded occasionally. The histic pergelic cryaquepts occur in poorly drained, low areas such as meander scars. They have thick surface organic...rHistic pergelic cryaquepts: soils with texture ranging from gravelly sand to clay, color from gray to olive grey, thick organic matter on surface

  20. Geology of the Prince William Sound and Kenai Peninsula region, Alaska

    Science.gov (United States)

    Wilson, Frederic H.; Hults, Chad P.

    2012-01-01

    The Prince William Sound and Kenai Peninsula region includes a significant part of one of the world’s largest accretionary complexes and a small part of the classic magmatic arc geology of the Alaska Peninsula. Physiographically, the map area ranges from the high glaciated mountains of the Alaska and Aleutian Ranges and the Chugach Mountains to the coastal lowlands of Cook Inlet and the Copper River delta. Structurally, the map area is cut by a number of major faults and postulated faults, the most important of which are the Border Ranges, Contact, and Bruin Bay Fault systems. The rocks of the map area belong to the Southern Margin composite terrane, a Tertiary and Cretaceous or older subduction-related accretionary complex, and the Alaska Peninsula terrane. Mesozoic rocks between these two terranes have been variously assigned to the Peninsular or the Hidden terranes. The oldest rocks in the map area are blocks of Paleozoic age within the mélange of the McHugh Complex; however, the protolith age of the greenschist and blueschist within the Border Ranges Fault zone is not known. Extensive glacial deposits mantle the Kenai Peninsula and the lowlands on the west side of Cook Inlet and are locally found elsewhere in the map area. This map was compiled from existing mapping, without generalization, and new or revised data was added where available.

  1. Streamflow and streambed scour in 2010 at bridge 339, Copper River, Alaska

    Science.gov (United States)

    Conaway, Jeffrey S.; Brabets, Timothy P.

    2011-01-01

    The Copper River Highway traverses a dynamic and complex network of braided and readily erodible channels that constitute the Copper River Delta, Alaska, by way of 11 bridges. Over the past decade, several of these bridges and the highway have sustained serious damage from both high and low flows and channel instability. This investigation studying the impact of channel migration on the highway incorporates data from scour monitoring, lidar surveys, bathymetry, hydrology, and time-lapse photography.

  2. Timber resource statistics for the Copper River inventory unit, Alaska, 1968.

    Science.gov (United States)

    Karl M. Hegg

    1975-01-01

    This first intensive forest inventory of Alaska's Copper River Valley found a commercial forest area of 287,800 acres with 303.8 million cubic feet of growing stock. Additionally, a noncommercial stratum was examined that had substantial standing volume but did not meet the growth criteria for commercial forest land. This stratum contained 152,800 acres with a...

  3. Hydrogeochemical and stream sediment reconnaissance basic data for Meade River quadrangle, Alaska

    International Nuclear Information System (INIS)

    1981-01-01

    Field and laboratory data are presented for 515 water samples from the Meade River Quadrangle, Alaska. The samples were collected by Los Alamos National Laboratory; laboratory analysis and data reporting were performed by the Uranium Resource Evaluation Project at Oak Ridge, Tennessee

  4. Hydrogeochemical and stream sediment reconnaissance basic data for Charley River Quadrangle, Alaska

    International Nuclear Information System (INIS)

    1981-01-01

    Field and laboratory data are presented for 1322 water samples from the Charley River Quadrangle, Alaska. The samples were collected by Los Alamos National Laboratory; laboratory analysis and data reporting were performed by the Uranium Resource Evaluation Project at Oak Ridge, Tennessee

  5. A survey of sport fish use on the Copper River Delta, Alaska.

    Science.gov (United States)

    Dirk W. Lang

    2010-01-01

    Aerial counts, in-person interviews, and mail-in questionnaires were used to survey sport fish use during the coho salmon (Oncorhynchus kisutch Walbaum) season on the Copper River Delta, Alaska from 2002 through 2006. Angler counts provided an index of use on individual streams and were used to develop a spatial database exhibiting patterns of use...

  6. Behavior and reproductive success of Rock Sandpipers breeding on the Yukon-Kuskokwim River Delta, Alaska

    NARCIS (Netherlands)

    Johnson, Matthew; Conklin, J.R.; Johnson, Branden; McCaffery, Brian J.; Haig, Susan M.; Walters, Jeffrey R.

    2009-01-01

    We studied Rock Sandpiper (Calidris ptilocnemis) breeding behavior and monitored reproductive success from 1998 to 2005 on the Yukon-Kuskokwim River Delta, Alaska, USA. We banded 24 adults and monitored 45 nests. Annual return rate of adults ranged between 67 and 100%. Six pairs of Rock Sandpipers

  7. Fire behavior, weather, and burn severity of the 2007 Anaktuvuk River tundra fire, North Slope, Alaska

    Science.gov (United States)

    Benjamin M. Jones; Crystal A. Kolden; Randi Jandt; John T. Abatzoglu; Frank Urban; Christopher D. Arp

    2009-01-01

    In 2007, the Anaktuvuk River Fire (ARF) became the largest recorded tundra fire on the North Slope of Alaska. The ARF burned for nearly three months, consuming more than 100,000 ha. At its peak in early September, the ARF burned at a rate of 7000 ha d-1. The conditions potentially responsible for this large tundra fire include modeled record high...

  8. The United States National Climate Assessment - Alaska Technical Regional Report

    Science.gov (United States)

    Markon, Carl J.; Trainor, Sarah F.; Chapin, F. Stuart; Markon, Carl J.; Trainor, Sarah F.; Chapin, F. Stuart

    2012-01-01

    The Alaskan landscape is changing, both in terms of effects of human activities as a consequence of increased population, social and economic development and their effects on the local and broad landscape; and those effects that accompany naturally occurring hazards such as volcanic eruptions, earthquakes, and tsunamis. Some of the most prevalent changes, however, are those resulting from a changing climate, with both near term and potential upcoming effects expected to continue into the future. Alaska's average annual statewide temperatures have increased by nearly 4°F from 1949 to 2005, with significant spatial variability due to the large latitudinal and longitudinal expanse of the State. Increases in mean annual temperature have been greatest in the interior region, and smallest in the State's southwest coastal regions. In general, however, trends point toward increases in both minimum temperatures, and in fewer extreme cold days. Trends in precipitation are somewhat similar to those in temperature, but with more variability. On the whole, Alaska saw a 10-percent increase in precipitation from 1949 to 2005, with the greatest increases recorded in winter. The National Climate Assessment has designated two well-established scenarios developed by the Intergovernmental Panel on Climate Change (Nakicenovic and others, 2001) as a minimum set that technical and author teams considered as context in preparing portions of this assessment. These two scenarios are referred to as the Special Report on Emissions Scenarios A2 and B1 scenarios, which assume either a continuation of recent trends in fossil fuel use (A2) or a vigorous global effort to reduce fossil fuel use (B1). Temperature increases from 4 to 22°F are predicted (to 2070-2099) depending on which emissions scenario (A2 or B1) is used with the least warming in southeast Alaska and the greatest in the northwest. Concomitant with temperature changes, by the end of the 21st century the growing season is expected

  9. Genetics, recruitment, and migration patterns of Arctic Cisco (Coregonus autumnalis) in the Colville River, Alaska and Mackenzie River, Canada

    Science.gov (United States)

    Zimmerman, Christian E.; Ramey, Andy M.; Turner, S.; Mueter, Franz J.; Murphy, S.; Nielsen, Jennifer L.

    2013-01-01

    Arctic cisco Coregonus autumnalis have a complex anadromous life history, many aspects of which remain poorly understood. Some life history traits of Arctic cisco from the Colville River, Alaska, and Mackenzie River basin, Canada, were investigated using molecular genetics, harvest data, and otolith microchemistry. The Mackenzie hypothesis, which suggests that Arctic cisco found in Alaskan waters originate from the Mackenzie River system, was tested using 11 microsatellite loci and a single mitochondrial DNA gene. No genetic differentiation was found among sample collections from the Colville River and the Mackenzie River system using molecular markers (P > 0.19 in all comparisons). Model-based clustering methods also supported genetic admixture between sample collections from the Colville River and Mackenzie River basin. A reanalysis of recruitment patterns to Alaska, which included data from recent warm periods and suspected changes in atmospheric circulation patterns, still finds that recruitment is correlated to wind conditions. Otolith microchemistry (Sr/Ca ratios) confirmed repeated, annual movements of Arctic cisco between low-salinity habitats in winter and marine waters in summer.

  10. Environmental protection in the Alligator Rivers Region

    International Nuclear Information System (INIS)

    Riley, G.

    1989-01-01

    One of a series of articles on the work of the Office of the Supervising Scientist for the Alligator Rivers Region (OSS) and its Alligator Rivers Region Research Institute (ARRRI), this discusses the environmental protection function of the OSS and the role of the ARRRI in achieving this

  11. Development and Calibration of Two-Dimensional Hydrodynamic Model of the Tanana River near Tok, Alaska

    Science.gov (United States)

    Conaway, Jeffrey S.; Moran, Edward H.

    2004-01-01

    Bathymetric and hydraulic data were collected by the U.S. Geological Survey on the Tanana River in proximity to Alaska Department of Transportation and Public Facilities' bridge number 505 at mile 80.5 of the Alaska Highway. Data were collected from August 7-9, 2002, over an approximate 5,000- foot reach of the river. These data were combined with topographic data provided by Alaska Department of Transportation and Public Facilities to generate a two-dimensional hydrodynamic model. The hydrodynamic model was calibrated with water-surface elevations, flow velocities, and flow directions collected at a discharge of 25,600 cubic feet per second. The calibrated model was then used for a simulation of the 100-year recurrence interval discharge of 51,900 cubic feet per second. The existing bridge piers were removed from the model geometry in a second simulation to model the hydraulic conditions in the channel without the piers' influence. The water-surface elevations, flow velocities, and flow directions from these simulations can be used to evaluate the influence of the piers on flow hydraulics and will assist the Alaska Department of Transportation and Public Facilities in the design of a replacement bridge.

  12. Loess ecosystems of northern Alaska: Regional gradient and toposequence at Prudhoe Bay

    International Nuclear Information System (INIS)

    Walker, D.A.; Everett, K.R.

    1991-01-01

    Loess-dominated ecosystems cover ∼ 14% (11,000 km 2 ) of the Arctic Coastal Plain and much of the northern portion of the Arctic Foothills. Knowledge of this poorly known ecosystem is important for sound land-use planning of the expanding developments in the region and for understanding the paleoecological dynamics of eolian systems that once dominated much of northern Alaska. A conceptual alkaline-tundra toposequence includes eight common vegetation types and associated soils and vegetation downwind of the Sagavanirktok River. Properties of loess tundra important for land-use planning include: (1) its high ice content, which contributes to its susceptibility to thermokarst; (2) high salinities, which hamper revegetation efforts; and (3) presence of certain plant species such as Dryas intergrifolia, which are particularly sensitive to disturbance. The loess gradient provides a natural analogue for road dust, and extensive disturbance associated with oil-field development

  13. Water Quality in the Tanana River Basin, Alaska, Water Years 2004-06

    Science.gov (United States)

    Moran, Edward H.

    2007-01-01

    OVERVIEW This report contains water-quality data collected from 84 sites in Tanana River basin during water years 2004 through 2006 (October 2003 through September 2006) as part of a cooperative study between the U.S. Geological Survey (USGS) and Alaska Department of Environmental Conservation (ADEC) Alaska Monitoring and Assessment Program (AKMAP), supported in part through the U.S. Environmental Protection Agency (USEPA) Office of Water, Cooperative Assistance Agreement X7-97078801. A broad range of chemical analyses are presented for 93 sets of samples collected at 59 tributaries to the Tanana River and at 25 locations along the mainstem. These data are to provide a means to assess baseline characteristics and establish indicators that are ecologically important, affordable, and relevant to society.

  14. Species List of Alaskan Birds, Mammals, Fish, Amphibians, Reptiles, and Invertebrates. Alaska Region Report Number 82.

    Science.gov (United States)

    Taylor, Tamra Faris

    This publication contains a detailed list of the birds, mammals, fish, amphibians, reptiles, and invertebrates found in Alaska. Part I lists the species by geographical regions. Part II lists the species by the ecological regions of the state. (CO)

  15. Regional shoreline change and coastal erosion hazards in Arctic Alaska

    Science.gov (United States)

    Gibbs, Ann E.; Richmond, Bruce M.; Erikson, Li H.; Harden, E. Lynne; Wallendorf, Louise

    2011-01-01

    Historical shoreline positions along the mainland Beaufort Sea coast of Alaska were digitized and analyzed to determine the long-term rate of change. Average shoreline change rates and ranges from 1947 to the mid-2000s were determined every 50 meters between Barrow and Demarcation Point, at the U.S.-Canadian border. Results show that shoreline change rates are highly variable along the coast, with an average regional shoreline change rate of-2.0 m/yr and localized rates of up to -19 m/yr. The highest erosion rates were observed at headlands, points, and associated with breached thermokarst lakes. Areas of accretion were limited, and generally associated with spit extension and minor beach accretion. In general, erosion rates increase from east to west, with overall higher rates east of Harrison Bay.

  16. Varying boreal forest response to Arctic environmental change at the Firth River, Alaska

    International Nuclear Information System (INIS)

    Andreu-Hayles, Laia; D'Arrigo, Rosanne; Anchukaitis, Kevin J; Beck, Pieter S A; Goetz, Scott; Frank, David

    2011-01-01

    The response of boreal forests to anthropogenic climate change remains uncertain, with potentially significant impacts for the global carbon cycle, albedo, canopy evapotranspiration and feedbacks into further climate change. Here, we focus on tree-ring data from the Firth River site at treeline in northeastern Alaska, in a tundra–forest transition region where pronounced warming has already occurred. Both tree-ring width (TRW) and maximum latewood density (MXD) chronologies were developed to identify the nature of tree growth and density responses to climatic and environmental changes in white spruce (Picea glauca), a dominant Arctic treeline species. Good agreement was found between the interannual fluctuations in the TRW chronology and summer temperatures from 1901 to 1950, whereas no significant relationships were found from 1951 to 2001, supporting evidence of significant divergence between TRW and summer temperature in the second half of the 20th century. In contrast to this unstable climatic response in the TRW record, the high frequency July–August temperature signal in the MXD series seems reasonably stable through the 20th century. Wider and denser rings were more frequent during the 20th century, particularly after 1950, than in previous centuries. Finally, comparison between the tree-ring proxies and a satellite-derived vegetation index suggests that TRW and MXD correlate with vegetation productivity at the landscape level at different times of the growing season.

  17. Topographic soil wetness index derived from combined Alaska-British Columbia datasets for the Gulf of Alaska region

    Science.gov (United States)

    D'Amore, D. V.; Biles, F. E.

    2016-12-01

    The flow of water is often highlighted as a priority in land management planning and assessments related to climate change. Improved measurement and modeling of soil moisture is required to develop predictive estimates for plant distributions, soil moisture, and snowpack, which all play important roles in ecosystem planning in the face of climate change. Drainage indexes are commonly derived from GIS tools with digital elevation models. Soil moisture classes derived from these tools are useful digital proxies for ecosystem functions associated with the concentration of water on the landscape. We developed a spatially explicit topographically derived soil wetness index (TWI) across the perhumid coastal temperate rainforest (PCTR) of Alaska and British Columbia. Developing applicable drainage indexes in complex terrain and across broad areas required careful application of the appropriate DEM, caution with artifacts in GIS covers and mapping realistic zones of wetlands with the indicator. The large spatial extent of the model has facilitated the mapping of forest habitat and the development of water table depth mapping in the region. A key element of the TWI is the merging of elevation datasets across the US-Canada border where major rivers transect the international boundary. The unified TWI allows for seemless mapping across the international border and unified ecological applications. A python program combined with the unified DEM allows end users to quickly apply the TWI to all areas of the PCTR. This common platform can facilitate model comparison and improvements to local soil moisture conditions, generation of streamflow, and ecological site conditions. In this presentation we highlight the application of the TWI for mapping risk factors related to forest decline and the development of a regional water table depth map. Improved soil moisture maps are critical for deriving spatial models of changes in soil moisture for both plant growth and streamflow across

  18. Defining interactions of in-stream hydrokinetic devices in the Tanana River, Alaska

    Science.gov (United States)

    Johnson, J.; Toniolo, H.; Seitz, A. C.; Schmid, J.; Duvoy, P.

    2012-12-01

    The acceptance, performance, and sustainability of operating in-stream hydrokinetic power generating devices in rivers depends on the impact of the river environment on hydrokinetic infrastructure as well as its impact on the river environment. The Alaska Hydrokinetic Energy Research Center (AHERC) conducts hydrokinetic "impact" and technology studies needed to support a sustainable hydrokinetic industry in Alaska. These include completed and ongoing baseline studies of river hydrodynamic conditions (river stage, discharge, current velocity, power, and turbulence; suspended and bed load sediment transport), ice, fish populations and behavior, surface and subsurface debris flows, and riverbed conditions. Technology and methods studies to minimize the effect of debris flows on deployed turbine system are in-progress to determine their effectiveness at reducing the probability of debris impact, diverting debris and their affect on available river power for conversion to electricity. An anchor point has been placed in the main flow just upstream of Main (Figure 1) to support projects and in preparation for future projects that are being planned to examine hydrokinetic turbine performance including power conversion efficiency, turbine drag and anchor chain loads, wake generation and effects on fish. Baseline fish studies indicate that hydrokinetic devices at the test site will have the most potential interactions with Pacific salmon smolts during their down-migration to the ocean in May and June. At the AHERC test site, the maximum turbulent kinetic energy (TKE) occurs just down stream from the major river bends (e.g., 000 and near the railroad bridge [upper center of the figure]) and over a deep hole at 440 (Figure 1), Minimum TKE occurs between main and 800. River current velocity measurements and simulations of river flow from 000 downstream past the railroad bridge indicate that the most stable current in the river reach is between Main and 800. The stable current

  19. Palaeomagnetism of lower cretaceous tuffs from Yukon-Kuskokwim delta region, western Alaska

    Science.gov (United States)

    Globerman, B.R.; Coe, R.S.; Hoare, J.M.; Decker, J.

    1983-01-01

    During the past decade, the prescient arguments1-3 for the allochthoneity of large portions of southern Alaska have been corroborated by detailed geological and palaeomagnetic studies in south-central Alaska 4-9 the Alaska Peninsula10, Kodiak Island11,12 and the Prince William Sound area13 (Fig. 1). These investigations have demonstrated sizeable northward displacements for rocks of late Palaeozoic, Mesozoic, and early Tertiary age in those regions, with northward motion at times culminating in collision of the allochthonous terranes against the backstop of 'nuclear' Alaska14,15. A fundamental question is which parts of Alaska underwent significantly less latitudinal translation relative to the 'stable' North American continent, thereby serving as the 'accretionary nucleus' into which the displaced 'microplates'16 were eventually incorporated17,18? Here we present new palaeomagnetic results from tuffs and associated volcaniclastic rocks of early Cretaceous age from the Yukon-Kuskokwin delta region in western Alaska. These rocks were probably overprinted during the Cretaceous long normal polarity interval, although a remagnetization event as recent as Palaeocene cannot be ruled out. This overprint direction is not appreciably discordant from the expected late Cretaceous direction for cratonal North America. The implied absence of appreciable northward displacement for this region is consistent with the general late Mesozoic-early Tertiary tectonic pattern for Alaska, based on more definitive studies: little to no poleward displacement for central Alaska, though substantially more northward drift for the 'southern Alaska terranes' (comprising Alaska Peninsula, Kodiak Island, Prince William Sound area, and Matunuska Valley) since late Cretaceous to Palaeocene time. ?? 1983 Nature Publishing Group.

  20. AFSC/REFM: Alaska regional economic data collected through surveys 2004, 2005, 2009, Seung

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Commercially available regional economic data for Alaska fisheries [such as IMpact analysis for PLANning (IMPLAN)] are unreliable. Therefore, these data need to be...

  1. PBO Operations in Alaska and Cascadia, Combining Regions and Collaborating with our Regional Partners

    Science.gov (United States)

    Austin, K. E.; Boyce, E. S.; Dausz, K.; Feaux, K.; Mattioli, G. S.; Pyatt, C.; Willoughby, H.; Woolace, A. C.

    2015-12-01

    During the last year, the Alaska and the Cascadia regions of the EarthScope Plate Boundary Observatory (PBO) network were combined into a single management unit. While both remain distinct regions with their own challenges and engineering staff, every effort has been made to operate as a single team to improve efficiency and provide the highest possible data quality and uptime. Over the last several years a concerted effort has been made to work collaboratively with other institutions and stakeholders to defray ongoing costs by sharing staff and resources. UNAVCO currently operates four integrated GPS/seismic stations in collaboration with the Alaska Earthquake Center, eight with the Alaska Volcano Observatory, and three with the EarthScope TA. By the end of 2015, PBO and TA plan to install another 3 integrated and/or co-located geodetic and seismic systems. While most of these are designed around existing PBO stations, the 2014 installation at Middleton Island is a new station for both groups, providing PBO with an opportunity to expand geodetic data in Alaska. There were two major joint maintenance efforts in 2015:, the largest was a 5 day mission among PBO, AVO, and TA, which shared boat, helicopter, and staff on and around Augustine Volcano; the second, was a 10 day helicopter mission shared between AVO and PBO on Unimak Island. PBO Pacific Northwest is working closely with University of Washington to co-locate at least 9 Earthquake Early Warning Systems, which include the addition of strong motion sensors and high speed RT telemetry at PBO sites. The project is managed by University of Washington but UNAVCO is providing land contact information and infrastructure support. Summer 2015 upgrades include a complete overhaul of aging radio technology at two major networks and several small radio networks in Cascadia. The upgrades will increase reliability and enhance the speed of existing telemetry infrastructure and will continue through summer 2018.

  2. 27 CFR 9.47 - Hudson River Region.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Hudson River Region. 9.47... Hudson River Region. (a) Name. The name of the viticultural area described in this section is “Hudson River Region.” (b) Approved maps. The approved maps for determining the boundaries of Hudson River...

  3. Hydraulic survey and scour assessment of Bridge 524, Tanana River at Big Delta, Alaska

    Science.gov (United States)

    Heinrichs, Thomas A.; Langley, Dustin E.; Burrows, Robert L.; Conaway, Jeffrey S.

    2007-01-01

    Bathymetric and hydraulic data were collected August 26–28, 1996, on the Tanana River at Big Delta, Alaska, at the Richardson Highway bridge and Trans-Alaska Pipeline crossing. Erosion along the right (north) bank of the river between the bridge and the pipeline crossing prompted the data collection. A water-surface profile hydraulic model for the 100- and 500-year recurrence-interval floods was developed using surveyed information. The Delta River enters the Tanana immediately downstream of the highway bridge, causing backwater that extends upstream of the bridge. Four scenarios were considered to simulate the influence of the backwater on flow through the bridge. Contraction and pier scour were computed from model results. Computed values of pier scour were large, but the scour during a flood may actually be less because of mitigating factors. No bank erosion was observed at the time of the survey, a low-flow period. Erosion is likely to occur during intermediate or high flows, but the actual erosion processes are unknown at this time.

  4. Interactions between brown bears and chum salmon at McNeil River, Alaska

    Science.gov (United States)

    Peirce, Joshua M.; Otis, Edward O.; Wipfli, Mark S.; Follmann, Erich H.

    2013-01-01

    Predation on returning runs of adult salmon (Oncorhynchus spp.) can have a large influence on their spawning success. At McNeil River State Game Sanctuary (MRSGS), Alaska, brown bears (Ursus arctos) congregate in high numbers annually along the lower McNeil River to prey upon returning adult chum salmon (O. keta). Low chum salmon escapements into McNeil River since the late 1990s have been proposed as a potential factor contributing to concurrent declines in bear numbers. The objective of this study was to determine the extent of bear predation on chum salmon in McNeil River, especially on pre-spawning fish, and use those data to adjust the escapement goal for the river. In 2005 and 2006, 105 chum salmon were radiotagged at the river mouth and tracked to determine cause and location of death. Below the falls, predators consumed 99% of tagged fish, killing 59% of them before they spawned. Subsequently, the escapement goal was nearly doubled to account for this pre-spawning mortality and to ensure enough salmon to sustain both predators and prey. This approach to integrated fish and wildlife management at MRSGS can serve as a model for other systems where current salmon escapement goals may not account for pre-spawning mortality.

  5. Airborne gamma-ray spectrometer and magnetometer survey, Meade River Quadrangle, Alaska. Final report

    International Nuclear Information System (INIS)

    1981-02-01

    The results obtained from an airborne high sensitivity gamma-ray spectrometer and magnetometer survey over the Meade River map area of Alaska are presented. Based on the criteria outlined in the general section on interpretation, a total of eight uranium anomalies have been outlined on the interpretation map. Most of these are only weakly to moderately anomalous. Zones 3 and 7 are relatively better than the others though none of the anomalies are thought to be of any economic significance. No follow-up work is recommended

  6. Pacific Northwest ampersand Alaska Regional Bioenergy Program. 1992--1993 yearbook with 1994 activities

    International Nuclear Information System (INIS)

    1994-04-01

    The U.S. Department of Energy administers five Regional Bioenergy Programs to encourage regionally specific application of biomass and municipal waste-to-energy technologies to local needs, opportunities and potentials. The Pacific Northwest and Alaska region has taken up a number of applied research and technology projects, and supported and guided its five participating state energy programs. This report describes the Pacific Northwest and Alaska Regional Bioenergy Program, and related projects of the state energy agencies, and summarizes the results of technical studies. It also considers future efforts of this regional program to meet its challenging assignment

  7. Initial Quantification of Suspended Sediment Loads for Three Alaska North Slope Rivers

    Directory of Open Access Journals (Sweden)

    Erica Lamb

    2016-09-01

    Full Text Available This study provides an initial assessment of suspended sediment transport in three rivers on the Alaska North Slope. From 2011 to 2013, the Anaktuvuk (69°27′51.00′′ N, 151°10′07.00′′ W, Chandler (69°17′0.30′′ N, 151°24′16.14′′ W, and Itkillik (68°51′59.46′′ N, 150°2′24.00′′ W Rivers were monitored for a variety of hydrologic, meteorologic, and sedimentologic characteristics. Watershed response to summer precipitation events was examined for each river. Bed sediment grain-size distribution was calculated using a photographic grid technique. Mean sediment diameters were 27.1 and 41.5 mm (Samples A and B for the Chandler, 35.8 mm for the Anaktuvuk, and 65.0 mm for the Itkillik. Suspended sediment rating curves were developed for each river. Suspended sediment discharge was analyzed. In 2011 and 2013, most of the total annual suspended sediment transport occurred during spring melt and widespread rainfall events, respectively. The results show that each river reacts differently to environmental inputs such as rain and basin characteristics.

  8. Radiotelemetry to estimate stream life of adult chum salmon in the McNeil River, Alaska

    Science.gov (United States)

    Peirce, Joshua M.; Otis, Edward O.; Wipfli, Mark S.; Follmann, Erich H.

    2011-01-01

    Estimating salmon escapement is one of the fundamental steps in managing salmon populations. The area-under-the-curve (AUC) method is commonly used to convert periodic aerial survey counts into annual salmon escapement indices. The AUC requires obtaining accurate estimates of stream life (SL) for target species. Traditional methods for estimating SL (e.g., mark–recapture) are not feasible for many populations. Our objective in this study was to determine the average SL of chum salmon Oncorhynchus keta in the McNeil River, Alaska, through radiotelemetry. During the 2005 and 2006 runs, 155 chum salmon were fitted with mortality-indicating radio tags as they entered the McNeil River and tracked until they died. A combination of remote data loggers, aerial surveys, and foot surveys were used to determine the location of fish and provide an estimate of time of death. Higher predation resulted in tagged fish below McNeil Falls having a significantly shorter SL (12.6 d) than those above (21.9 d). The streamwide average SL (13.8 d) for chum salmon at the McNeil River was lower than the regionwide value (17.5 d) previously used to generate AUC indices of chum salmon escapement for the McNeil River. We conclude that radiotelemetry is an effective tool for estimating SL in rivers not well suited to other methods.

  9. 77 FR 11022 - Approval and Promulgation of Implementation Plans; State of Alaska; Regional Haze State...

    Science.gov (United States)

    2012-02-24

    ... protocol was developed. See Figure III.K.5-2 of the SIP submittal. Included Sources--Emission sources... Implementation Plan (SIP) revision, submitted by the State of Alaska on April 4, 2011, as meeting the.... Requirements for Regional Haze SIPs A. The CAA and the Regional Haze Rule B. Baseline, Natural Conditions, and...

  10. Medial moraines of glaciers of the Copper River Basin, Alaska: Discrete landslides dominate over other sources

    Science.gov (United States)

    Kargel, J. S.; Fischer, L.; Furfaro, R.; Huggel, C.; Korup, O.; Leonard, G. J.; Uhlmann, M.; Wessels, R. L.; Wolfe, D. F.

    2009-12-01

    Medial moraines are visually dominant structures of most large valley glaciers in the Copper River Basin (CRB), Alaska. Areally extensive but thin (usually rock falls and talus creep; rocks delivered via snow and ice avalanches; ingestion of lateral moraines along tributary convergences; and basal erosional debris. Evidence indicates that in CRB glaciers, discrete large avalanches predominate as the major contributors of moraine mass. Subglacial erosional debris is predominantly pulverized to small grain sizes and flushed. Many large, young avalanches exist on CRB glaciers. Evidence from colorimetry indicates that many medial moraines actually are landslides that have been sheared and swept downglacier, thus mimicking the form of other types of medial moraines formed where tributaries coalesce and flow down valley. Landcover classification of ASTER imagery, qualitative observations from air photos, and semiquantitative field-based estimations of rock color types indicate that on Allen Glacier, and other CRB glaciers, landslides are the sources of most medial moraines. On Allen and Root Glacier, for example, we see very few boulders with obvious signs of basal abrasion, whereas nearly all boulders exhibit signs of irregular fracture, for example in landslides. Such landslides have large effects on the thermal and mass balance of CRB glaciers, sometimes opposing or in other cases accentuating the effects of global/regional climate change. Considering the link between landslides and seismicity, and that Magnitude 8-9 earthquakes may occur nearby only about once a century, which is also the characteristic response time of large glaciers to climate shifts, seismicity must be considered along with climate change induced glacier responses in the CRB. Ultimately, climate has the final word, and already this is evident in the glacier record. Glacial flour is probably almost entirely from bed erosion. We will present estimates of the contributions of landslides and

  11. Vegetation and Environmental Gradients of the Prudhoe Bay Region, Alaska,

    Science.gov (United States)

    1985-09-01

    Agricultural Experiment Station, Palmer Research Cen- ter, University of Alaska, analyzed the soil nutrients. Tom Boldin , technician at the I University of...misidentified of the extract utilized the Technicon Autoanalyzer taxa. Most of these have been noted in the anno- industrial method No. 94-70W...orthophosphate in tated checklist of plants (Appendix A). water and wastewater). Nitrogen was analyzed with an extracting solution of 2N HCI and utilized

  12. Hydrology and modeling of flow conditions at Bridge 339 and Mile 38-43, Copper River Highway, Alaska

    Science.gov (United States)

    Brabets, Timothy P.

    2012-01-01

    The Copper River basin, the sixth largest watershed in Alaska, drains an area of 24,200 square miles in south-central Alaska. This large, glacier-fed river flows across a wide alluvial fan before it enters the Gulf of Alaska. The Copper River Highway, which traverses the alluvial fan, has been affected by channel planform reconfiguration. Currently (2012), two areas of the Copper River Highway are at risk: at Mile 38-43, the road grade is too low and the highway could be flooded by high flows of the Copper River, and at Mile 36, the main channel of the Copper River has migrated directly toward Bridge 339. Because Bridge 339 was not designed and built to convey the main flow of the Copper River, as much as 50 feet of scour occurred at the piers in 2011. The piers can no longer absorb the lateral or vertical loads, resulting in closure of the bridge and the Copper River Highway. The U.S. Geological Survey Flow and Sediment Transport with Morphologic Evolution of Channels (FaSTMECH) model was used to simulate the flow of the Copper River and produce simulations of depth, water-surface elevation, and velocity. At the Mile 38-43 area, FaSTMECH was used to analyze the effects of raising the road grade 5 feet, and at Mile 36, FaSTMECH was used to analyze the effects of constructing a channel to divert flow away from Bridge 339. Results from FaSTMECH indicate that if raising the road grade 5 feet in the Mile 38-43 area, a flood with an annual exceedance probability of 2 percent (400,000 cubic feet per second) would not overtop the highway. In the Bridge 339 area, results from FaSTMECH indicate that a design channel could divert flows as much as 100,000 cubic feet per second away from Bridge 339.

  13. Remote identification of maternal polar bear (Ursus maritimus) denning habitat on the Colville River Delta, Alaska

    Science.gov (United States)

    Blank, Justin J.

    High resolution digital aerial photographs (1 foot pixel size) of the Colville River Delta, Alaska were examined in 3D, with the use of a digital photogrammetric workstation. Topographic features meeting the criteria required for adequate snow accumulation, and subsequent construction of terrestrial polar bear maternal dens, were identified and digitized into an ArcGIS line shapefile. Effectiveness, efficiency, and accuracy were improved when compared to previous polar bear denning habitat efforts which utilized contact photo prints and a pocket stereoscope in other geographic areas of northern Alaska. Accuracy of photograph interpretation was systematically evaluated visually from the air with the use of a helicopter and physically on the ground. Results show that the mapping efforts were successful in identifying den habitat 91.3% of the time. Knowledge denning habitat can improve and inform decision making by managers and regulators when considering travel and development in the study area. An understanding of polar bear denning habitat extent and location will be a crucial tool for planning activities within the study area in a way that minimizes conflicts with maternal dens.

  14. Electronic tags and genetics explore variation in migrating steelhead kelts (oncorhynchus mykiss), Ninilchik river, Alaska

    Science.gov (United States)

    Nielsen, J.L.; Turner, S.M.; Zimmerman, C.E.

    2011-01-01

    Acoustic and archival tags examined freshwater and marine migrations of postspawn steelhead kelts (Oncorhynchus mykiss) in the Ninilchik River, Alaska, USA. Postspawn steelhead were captured at a weir in 2002-2005. Scale analysis indicated multiple migratory life histories and spawning behaviors. Acoustic tags were implanted in 99 kelts (2002-2003), and an array of acoustic receivers calculated the average speed of outmigration, timing of saltwater entry, and duration of residency in the vicinity of the river mouth. Ocean migration data were recovered from two archival tags implanted in kelts in 2004 (one male and one female). Archival tags documented seasonal differences in maximum depth and behavior with both fish spending 97% of time at sea <6 m depth (day and night). All study fish were double tagged with passive integrated transponder (PIT) tags implanted in the body cavity. Less than 4% of PIT tags were retained in postspawn steelhead. Molecular genetics demonstrated no significant differences in genetic population structure across years or among spawning life history types, suggesting a genetically panmictic population with highly diverse life history characteristics in the Ninilchik River.

  15. Forest dynamics in the temperate rainforests of Alaska: from individual tree to regional scales

    Science.gov (United States)

    Tara M. Barrett

    2015-01-01

    Analysis of remeasurement data from 1079 Forest Inventory and Analysis (FIA) plots revealed multi-scale change occurring in the temperate rainforests of southeast Alaska. In the western half of the region, including Prince William Sound, aboveground live tree biomass and carbon are increasing at a rate of 8 ( ± 2 ) percent per decade, driven by an increase in Sitka...

  16. 75 FR 59687 - Proposed Information Collection; Comment Request; Alaska Region Bering Sea & Aleutian Islands...

    Science.gov (United States)

    2010-09-28

    ... among harvesters, processors, and coastal communities and monitors the ``economic stability for... Collection; Comment Request; Alaska Region Bering Sea & Aleutian Islands (BSAI) Crab Economic Data Reports... CR Program's mandatory economic data collection report (EDR) used to assess the efficacy of the CR...

  17. Urban rivers as hotspots of regional nitrogen pollution

    International Nuclear Information System (INIS)

    Zhang, Xiaohong; Wu, Yiyun; Gu, Baojing

    2015-01-01

    Excess nitrogen inputs to terrestrial ecosystems via human activities have deteriorated water qualities on regional scales. Urban areas as settlements of over half global population, however, were usually not considered in the analysis of regional water pollution. Here, we used a 72-month monitoring data of water qualities in Hangzhou, China to test the role of urban rives in regional nitrogen pollution and how they response to the changes of human activities. Concentrations of ammonium nitrogen in urban rivers were 3–5 times higher than that in regional rivers. Urban rivers have become pools of reactive nitrogen and hotspots of regional pollution. Moreover, this river pollution is not being measured by current surface water monitoring networks that are designed to measure broader regional patterns, resulting in an underestimation of regional pollution. This is crucial to urban environment not only in China, but also in other countries, where urban rivers are seriously polluted. - Highlights: • Nitrogen concentrations in urban rivers are much higher than that in regional rivers. • Domestic wastewater is the main source of urban river pollution in Hangzhou. • Pollutant collecting and water diversion can sharply reduce the urban river pollution. - Urban river pollution is not being measured by the current monitoring networks that are designed to measure regional patterns causing an underestimation

  18. Braid-plain dynamics and bank erosion along the Matanuska River, Alaska

    Science.gov (United States)

    Curran, J. H.

    2009-12-01

    Braid-plain activity and geomorphic features in the Matanuska River in southcentral Alaska between 1949 and 2006 were examined to support a bank erosion hazard assessment. The glacial Matanuska River drains 6,500 km2 and is braided for 85 percent of its 150 km course, which parallels a major highway and flows through the towns of Sutton and Palmer, Alaska. The historical braid plain was defined as the envelope of areas with active channels, unvegetated bars, or vegetated bars with evidence of channels since 1949 and delineated in a GIS from 1949, 1962, and 2006 aerial orthoimagery. We created a strip map of bank height and composition (primarily bedrock and unconsolidated sediment) at braid-plain margins and outlined valley bottom features (terraces and tributary fans) adjacent to the braid plain to assess erodibility. Braid-plain dynamism has created a mosaic of extensive lightly vegetated bars interspersed with forested bars in strips along the banks and in small mid-channel positions. Abandoned channels filled with groundwater or tributary streamflow have created clearwater side channels within these bars that serve as the primary spawning location for chum, sockeye, and coho salmon in the Matanuska River basin. Erosion magnitudes for the periods 1949-1962 and 1962-2006 were computed as braid-plain expansion at transects across the historical braid-plain boundaries. Episodic, spatially distributed erosion and the antiquity of some eroded surfaces suggests that average annual erosion rates at a location are not adequate for assessing future erosion at that location in a braid plain. Lateral expansion caused bank erosion of 100 -275 m at 20 locations over the full period, about half at tributary fans and most occurring in a single time period. Minor growth of tributary fans constricted the braid plain, and emerging terraces have the potential to shrink the braid plain. Eroded banks included undated but pre-historic fluvial terraces and tributary fans. Where

  19. 76 FR 30956 - Outer Continental Shelf, Alaska OCS Region, Chukchi Sea Planning Area, Oil and Gas Lease Sale 193

    Science.gov (United States)

    2011-05-27

    ... Point Hope et al., v. Salazar, No. 1:08-cv-00004-RRB (D. Alaska)]. The sale was conducted in February... Continental Shelf, Alaska OCS Region, Chukchi Sea Planning Area, Oil and Gas Lease Sale 193 AGENCY: Bureau of...: BOEMRE announces the availability of a Revised Draft SEIS, OCS Oil and Gas Lease Sale 193, Chukchi Sea...

  20. Effect of ice formation and streamflow on salmon incubation habitat in the lower Bradley River, Alaska

    Science.gov (United States)

    Rickman, R.L.

    1996-01-01

    A minimum flow of 40 cubic feet per second is required in the lower Bradley River, near Homer, Alaska, from November 2 to April 30 to ensure adequate salmon egg incubation habitat. The study that determined this minimum flow did not account for the effects of ice formation on habitat. An investigation was made during periods of ice formation. Hydraulic properties and field water-quality data were measured in winter only from March 1993 to April 1995 at six transects in the lower Bradley River. Discharge in the lower Bradley River ranged from 42.6 to 73.0 cubic feet per second (average 57 cubic feet per second) with ice conditions ranging from near ice free to 100 percent ice cover. Stream water velocity and depth were adequate for habitat protection for all ice conditions and discharges. No relation was found between percent ice cover and mean velocity and depth for any given discharge and no trends were found with changes in discharge for a given ice condition. Velocity distribution within each transect varied significantly from one sampling period to the next. Mean depth and velocity at flows of 40 cubic feet per second or less could not be predicted. No consistent relation was found between the amount of wetted perimeter and percent ice cover. Intragravel-water temperature was slightly warmer than surface-water temperature. Surface and intragravel-water dissolved-oxygen levels were adequate for all flows and ice conditions. No apparent relation was found between dissolved-oxygen levels and streamflow or ice conditions. Excellent oxygen exchange was indicated throughout the study reach. Stranding potential of salmon fry was found to be low throughout the study reach. The limiting factors for determining the minimal acceptable flow limit appear to be stream-water velocity and depth, although specific limits could not be estimated because of the high flows that occurred during this study.

  1. Wind Energy Resource Assessment on Alaska Native Lands in Cordova Region of Prince William Sound

    Energy Technology Data Exchange (ETDEWEB)

    Whissel, John C. [Native Village of Eyak, Cordova, AK (United States); Piche, Matthew [Native Village of Eyak, Cordova, AK (United States)

    2015-06-29

    The Native Village of Eyak (NVE) has been monitoring wind resources around Cordova, Alaska in order to determine whether there is a role for wind energy to play in the city’s energy scheme, which is now supplies entirely by two run-of-the-river hydro plants and diesel generators. These data are reported in Appendices A and B. Because the hydro resources decline during winter months, and wind resources increase, wind is perhaps an ideal counterpart to round out Cordova’s renewable energy supply. The results of this effort suggests that this is the case, and that developing wind resources makes sense for our small, isolated community.

  2. Geomorphic Controls on Floodplain Soil Organic Carbon in the Yukon Flats, Interior Alaska, From Reach to River Basin Scales

    Science.gov (United States)

    Lininger, K. B.; Wohl, E.; Rose, J. R.

    2018-03-01

    Floodplains accumulate and store organic carbon (OC) and release OC to rivers, but studies of floodplain soil OC come from small rivers or small spatial extents on larger rivers in temperate latitudes. Warming climate is causing substantial change in geomorphic process and OC fluxes in high latitude rivers. We investigate geomorphic controls on floodplain soil OC concentrations in active-layer mineral sediment in the Yukon Flats, interior Alaska. We characterize OC along the Yukon River and four tributaries in relation to geomorphic controls at the river basin, segment, and reach scales. Average OC concentration within floodplain soil is 2.8% (median = 2.2%). Statistical analyses indicate that OC varies among river basins, among planform types along a river depending on the geomorphic unit, and among geomorphic units. OC decreases with sample depth, suggesting that most OC accumulates via autochthonous inputs from floodplain vegetation. Floodplain and river characteristics, such as grain size, soil moisture, planform, migration rate, and riverine DOC concentrations, likely influence differences among rivers. Grain size, soil moisture, and age of surface likely influence differences among geomorphic units. Mean OC concentrations vary more among geomorphic units (wetlands = 5.1% versus bars = 2.0%) than among study rivers (Dall River = 3.8% versus Teedrinjik River = 2.3%), suggesting that reach-scale geomorphic processes more strongly control the spatial distribution of OC than basin-scale processes. Investigating differences at the basin and reach scale is necessary to accurately assess the amount and distribution of floodplain soil OC, as well as the geomorphic controls on OC.

  3. Seroprevalence of Brucella antibodies in harbor seals in Alaska, USA, with age, regional, and reproductive comparisons.

    Science.gov (United States)

    Hoover-Miller, A; Dunn, J L; Field, C L; Blundell, G; Atkinson, S

    2017-09-20

    Populations of harbor seal Phoca vitulina in the Gulf of Alaska have dramatically declined during the past 4 decades. Numbers of seals in Glacier Bay, in southeast Alaska, USA, have also declined despite extensive protection. Causes of the declines and slow recovery are poorly understood. Brucellosis is a zoonotic disease that adversely affects reproduction in many domestic species. We measured the seroprevalence of Brucella antibodies in 554 harbor seals in 3 Alaska locations: Prince William Sound (PWS), Glacier Bay (GB), and Tracy Arm Fords Terror (TAFT) Wilderness Area. Objectives included testing for regional, sex, age, and female reproductive state differences in Brucella antibody seroprevalence, persistence in titers in recaptured seals, and differences in titers between mother seals and their pups. Overall, 52% of adults (AD), 53% of subadults (SA), 77% of yearlings (YRL), and 26% of Brucella. Results show higher seroprevalence (64%) for AD and SA seals in the depressed and declining populations in PWS and GB than in TAFT (29%). Lactating females were less likely to be seropositive than other AD females, including pregnant females. Further research is needed to seek evidence of Brucella infection in Alaskan harbor seals, identify effects on neonatal viability, and assess zoonotic implications for Alaska Natives who rely on harbor seals for food.

  4. The Federal Government and the Alligator Rivers Region

    International Nuclear Information System (INIS)

    BURTON, A.

    1989-01-01

    The administrative framework put in place by the Commonwealth and Northern Territory governments to monitor mining activities in the Alligator Rivers Region is presented. The key institutional element is the Coordinating Committee for the Alligator Rivers Region chaired and serviced by the Supervising Scientist and established through legislation

  5. Spatially explicit estimation of aboveground boreal forest biomass in the Yukon River Basin, Alaska

    Science.gov (United States)

    Ji, Lei; Wylie, Bruce K.; Brown, Dana R. N.; Peterson, Birgit E.; Alexander, Heather D.; Mack, Michelle C.; Rover, Jennifer R.; Waldrop, Mark P.; McFarland, Jack W.; Chen, Xuexia; Pastick, Neal J.

    2015-01-01

    Quantification of aboveground biomass (AGB) in Alaska’s boreal forest is essential to the accurate evaluation of terrestrial carbon stocks and dynamics in northern high-latitude ecosystems. Our goal was to map AGB at 30 m resolution for the boreal forest in the Yukon River Basin of Alaska using Landsat data and ground measurements. We acquired Landsat images to generate a 3-year (2008–2010) composite of top-of-atmosphere reflectance for six bands as well as the brightness temperature (BT). We constructed a multiple regression model using field-observed AGB and Landsat-derived reflectance, BT, and vegetation indices. A basin-wide boreal forest AGB map at 30 m resolution was generated by applying the regression model to the Landsat composite. The fivefold cross-validation with field measurements had a mean absolute error (MAE) of 25.7 Mg ha−1 (relative MAE 47.5%) and a mean bias error (MBE) of 4.3 Mg ha−1(relative MBE 7.9%). The boreal forest AGB product was compared with lidar-based vegetation height data; the comparison indicated that there was a significant correlation between the two data sets.

  6. Uranium concentrations in lake and stream waters and sediments from selected sites in the Susitna River Basin, Alaska

    International Nuclear Information System (INIS)

    Hill, D.E.

    1977-03-01

    During the summer of 1976, 141 water and 211 sediment samples were taken from 147 locations in the Susitna River basin in Alaska by the Geophysical Institute of the University of Alaska for the LASL. These samples were taken to provide preliminary information on the uranium concentrations in waters and sediments from the Susitna River basin and to test the analytical methods proposed for the NURE Hydrogeochemical and Stream Sediment Reconnaissance for uranium in Alaska. The uranium determinations resulting from the fluorometric analysis of the water samples and the delayed-neutron counting of the sediment samples are presented. The low levels of uranium in the water samples, many of which were below the detectable limit of the LASL fluorometric technique, indicate that a more sensitive analytical method is needed for the analysis of Alaskan water samples from this area. An overlay showing numbered sample locations and overlays graphically portraying the concentrations of uranium in the water and sediment samples, all at 1:250,000 scale for use with existing USGS topographic sheets, are also provided as plates

  7. Investigation of Alaska's uranium potential

    International Nuclear Information System (INIS)

    Eakins, G.R.

    1975-01-01

    Of the various geographical regions in Alaska that were examined in an exhaustive literary search for the possibility of uranium--either vein type or sedimentary--six offer encouragement: the Copper River Basin, the alkaline intrusive belt of west-central Alaska and Selawik Basin area, the Seward Peninsula, the Susitna Lowland, the coal-bearing basins of the north flank of the Alaska Range, the Precambrian gneisses of the USGS 1:250,000 Goodnews quadrangle, and Southeastern Alaska, which has the sole operating uranium mine in the state. Other areas that may be favorable for the presence of uranium include the Yukon Flats area, the Cook Inlet Basin, and the Galena Basin

  8. Pacific Northwest and Alaska Regional Bioenergy Program : Five Year Report, 1985-1990.

    Energy Technology Data Exchange (ETDEWEB)

    Pacific Northwest and Alaska Bioenergy Program (U.S.)

    1991-02-01

    This five-year report describes activities of the Pacific Northwest and Alaska Regional Bioenergy Program between 1985 and 1990. Begun in 1979, this Regional Bioenergy Program became the model for the nation's four other regional bioenergy programs in 1983. Within the time span of this report, the Pacific Northwest and Alaska Regional Bioenergy Program has undertaken a number of applied research and technology projects, and supported and guided the work of its five participating state energy programs. During this period, the Regional Bioenergy Program has brought together public- and private-sector organizations to promote the use of local biomass and municipal-waste energy resources and technologies. This report claims information on the mission, goals and accomplishments of the Regional Bioenergy Program. It describes the biomass projects conducted by the individual states of the region, and summarizes the results of the programs technical studies. Publications from both the state and regional projects are listed. The report goes on to consider future efforts of the Regional Bioenergy Program under its challenging assignment. Research activities include: forest residue estimates; Landsat biomass mapping; woody biomass plantations; industrial wood-fuel market; residential space heating with wood; materials recovery of residues; co-firing wood chips with coal; biomass fuel characterization; wood-boosted geothermal power plants; wood gasification; municipal solid wastes to energy; woodstove study; slash burning; forest depletion; and technology transfer. 9 figs., 6 tabs.

  9. A promising tool for subsurface permafrost mapping-An application of airborne geophysics from the Yukon River Basin, Alaska

    Science.gov (United States)

    Abraham, Jared E.

    2011-01-01

    Permafrost is a predominant physical feature of the Earth's Arctic and Subarctic clines and a major consideration encompassing ecosystem structure to infrastructure engineering and placement. Perennially frozen ground is estimated to cover about 85 percent of the state of Alaska where northern reaches are underlain with continuous permafrost and parts of interior Alaska are underlain by areas of discontinuous and (or) sporadic permafrost (fig. 1). The region of Interior Alaska, where permafrost is scattered among unfrozen ground, is a complex mosaic of terrains and habitats. Such diversity creates arrays of lakes and surface-water and groundwater patterns that continental populations of migratory waterfowl and internationally significant fisheries have adapted to over time. A road or pipeline might pass over frozen and unfrozen ground, affecting the types of materials and engineering approaches needed to sustain the infrastructure.

  10. Year-round Regional CO2 Fluxes from Boreal and Tundra Ecosystems in Alaska

    Science.gov (United States)

    Commane, R.; Lindaas, J.; Benmergui, J. S.; Luus, K. A.; Chang, R. Y. W.; Daube, B. C.; Euskirchen, E. S.; Henderson, J.; Karion, A.; Miller, J. B.; Miller, S. M.; Parazoo, N.; Randerson, J. T.; Sweeney, C.; Tans, P. P.; Thoning, K. W.; Veraverbeke, S.; Miller, C. E.; Wofsy, S. C.

    2016-12-01

    High-latitude ecosystems could release large amounts of carbon dioxide (CO2) to the atmosphere in a warmer climate. We derive temporally and spatially resolved year-round CO2 fluxes in Alaska from a synthesis of airborne and tower CO2 observations in 2012-2014. We find that tundra ecosystems were net sources of atmospheric CO2. We discuss these flux estimates in the context of long-term CO2 measurements at Barrow, AK, to asses the long term trend in carbon fluxes in the Arctic. Many Earth System Models incorrectly simulate net carbon uptake in Alaska presently. Our results imply that annual net emission of CO2 to the atmosphere may have increased markedly in this region of the Arctic in response to warming climate, supporting the view that climate-carbon feedback is strongly positive in the high Arctic.

  11. Philosophy of river problems: local to regional, static to mobile

    International Nuclear Information System (INIS)

    Jansky, L.

    1997-01-01

    According to the statistics, thirteen of the twenty-five major river basins in Europe are basins of transboundary rivers. The Danube river basin is largest transboundary river basin in Europe. Almost in each case the local and regional problems arise, like division of fishing rights (or rights on river beds), right to claim tolls on navigation, how to adjust boundaries if the channel moves, or rights to claim duty on crossing the river, or to build bridges, weirs, etc. All the above problems on a larger scale include also rights of non-contiguous lands (i.e. not fronting on the river) to use the river for navigation, for passage of migrating fish, to exploit river (e.g. bed sediments) without damage by one country or society to another below. Similarly, pollution and large-scale removal of water, are problems on regional or national levels. Disputes usually arise from the above, more or less exacerbated by their superimposition or other non-river problems, e.g. religion, politics, historical issues, recent aggression, relative prosperity, expanding economy vs. contrasting economy. May be cause or consequence of many of these. And somewhere here is likely the case of Gabcikovo on Danube between Slovakia and Hungary, as well. (author)

  12. Glacial Fluctuation in the Source Region of the Yangtze River

    International Nuclear Information System (INIS)

    Shengyi, Gao; Qingsong, Fan; Xi, Cao; Li, Ma

    2014-01-01

    Glaciers in the source region of the Yangtze River are not only water resources but also important energy and environmental resources. Glacial fluctuation is an important component of the study of changes in the natural environment, including climate change. We investigated the glaciers in the source region of the Yangtze River, and analyzed the fluctuations using multi-temporal remote sensing data. The trend in glacial fluctuation and the factors that influence it were determined. The results have implications for water resource management and environmental conservation in the Yangtze River region

  13. Sources and Reactivity of Terrestrial Organic Carbon to the Colville River Delta, Beaufort Sea, Alaska

    Science.gov (United States)

    Schreiner, K. M.; Bianchi, T. S.; Rosenheim, B. E.

    2014-12-01

    Terrestrial particulate organic carbon (tPOC) delivery to nearshore deltaic regions is an important mechanism of OC storage and burial, and continental margins worldwide account for approximately 90% of the carbon burial in the ocean. Increasing warming in the Arctic is leading to an acceleration of the hydrologic cycle, warming of permafrost, and broad shifts in vegetation. All of these changes are likely to affect the delivery, reactivity, and burial of tPOC in nearshore Arctic regions, making the Arctic an ideal place to study the effects of climate change on tPOC delivery. However, to date, most studies of tPOC delivery from North America to the Arctic Ocean have focused on large Arctic rivers like the Mackenzie and Yukon, and a significant portion of those watersheds lie in sub-Arctic latitudes, meaning that their tPOC delivery is likely not uniquely representative of the high Arctic tundra. Here, we focus on tPOC delivery by the Colville River, the largest North American river with a watershed that does not include sub-Arctic latitudes. Sediment samples from the river delta and nearby Simpson's Lagoon were taken in August of 2010 and subsequently fractionated by density, in order to study the delivery of both discrete and sediment-sorbed tPOC. Samples were analyzed for stable carbon isotopes, bulk radiocarbon, terrestrial biomarkers (including lignin-phenols, and other CuO reaction products), and aquatic biomarkers (algal pigments), and additionally a subset of the samples were analyzed by ramped pyrolysis-14C. Results show that tPOC delivery near the river mouth is sourced from coastal plain tundra, with additional delivery of tPOC from peat released into the lagoon from the seaward limit of the tundra by coastal erosion. Ramped pyrolysis-14C analysis also shows a clear differentiation between tPOC delivered by the river and tPOC delivered by coastal retreat in the lagoon. Additionally, a significant portion of the OC released by the Colville River is

  14. Colonial Education and Women of the Cross River Region of ...

    African Journals Online (AJOL)

    As a result, there is a gap to be filled in this respect, in the historiography of the Cross River region. This is the concern of this paper. The paper reveals that the women of present-day Cross River State contributed to the educational development of their communities in cash and kind. Even of greater importance is that a few ...

  15. Regional Cooperation Efforts in the Mekong River Basin: Mitigating river-related security threats and promoting regional development

    Directory of Open Access Journals (Sweden)

    Susanne Schmeier

    2009-01-01

    Full Text Available The development of international rivers is often perceived as leading to conflicts or even water wars. However, as the development of the Mekong River shows, cooperation has not only prevailed in the last decades, but River Basin Organizations (RBOs, established to mitigate river-related conflicts and/or develop the river basin, have also contributed to the emergence of more general cooperation structures, mainly by creating spill-over effects in other issue-areas, bringing cooperation to policy fields beyond the river itself. This article assesses the contribution of the Mekong River Commission (MRC and the Greater Mekong Sub-Region (GMS to the sustainable development of the Mekong Region as well as to the promotion of regional cooperation in mainland South-East Asia in general. --- Die Entwicklung grenzüberschreitender Flüsse wird oft mit Konflikten oder gar Kriegen um Wasser assoziiert. Wie jedoch die Entwicklung im Mekong-Becken zeigt, waren die vergangenen Jahrzehnte nicht nur von Kooperation gezeichnet, sondern Flussbeckenorganisationen konnten außerdem dazu beitragen, weitreichendere Kooperationsstrukturen zu entwickeln, die sich auf andere Politikfelder ausdehnen. Dieser Artikel beschäftigt sich mit dem Beitrag der Mekong River Commission (MRC und der Greater Mekong Sub-Region (GMS zur nachhaltigen Entwicklung in der Mekong Region sowie zur Förderung allgemeiner regionaler Kooperation im Festländischen Südostasien.

  16. Uranium hydrogeochemical and stream-sediment reconnaissance of the Utukok River NTMS quadrangle, Alaska

    International Nuclear Information System (INIS)

    Langfeldt, S.L.; Hardy, L.C.; D'Andrea, R.F. Jr.; Zinkl, R.J.; Shettel, D.L. Jr.

    1982-03-01

    This report presents results of a Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Utukok River NTMS quadrangle, Alaska. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form. These machine-readable data, as well as quarterly or semiannual program progress reports containing further information on the HSSR program in general, or on the Los Alamos National Laboratory (LANL) portion of the program in particular, are available from DOE's Technical Library at its Grand Junction Area Office. Presented in this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume; these data are, however, available on the magnetic tape. Appendices A and B describe the sample media and summarize the analytical results for each medium. The data have been subdivided by one of the Los Alamos National Laboratory sorting programs of Zinkl and others (1981a) into stream-sediment and lake-sediment samples. For each group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1;1,000,000 scale maps of pertinent elements have been included in this report. Also included are maps showing results of multivariate statistical analyses. Information on the field and analytical procedures used by the Los Alamos National Laboratory during sample collection and analysis may be found in any HSSR data release prepared by the Laboratory and will not be included in this report

  17. Does winter region affect spring arrival time and body mass of king eiders in northern Alaska?

    Science.gov (United States)

    Powell, Abby N.; Oppel, Steffen

    2009-01-01

    Events during the non-breeding season may affect the body condition of migratory birds and influence performance during the following breeding season. Migratory birds nesting in the Arctic often rely on endogenous nutrients for reproductive efforts, and are thus potentially subject to such carry-over effects. We tested whether king eider (Somateria spectabilis) arrival time and body mass upon arrival at breeding grounds in northern Alaska were affected by their choice of a winter region in the Bering Sea. We captured birds shortly after arrival on breeding grounds in early June 2002–2006 at two sites in northern Alaska and determined the region in which individuals wintered using satellite telemetry or stable isotope ratios of head feathers. We used generalized linear models to assess whether winter region explained variation in arrival body mass among individuals by accounting for sex, site, annual variation, and the date a bird was captured. We found no support for our hypothesis that either arrival time or arrival body mass of king eiders differed among winter regions. We conclude that wintering in different regions in the Bering Sea is unlikely to have reproductive consequences for king eiders in our study areas.

  18. Distribution of branched GDGTs in surface sediments from the Colville River, Alaska: Implications for the MBT'/CBT paleothermometer in Arctic marine sediments

    Science.gov (United States)

    Hanna, Andrea J. M.; Shanahan, Timothy M.; Allison, Mead A.

    2016-07-01

    Significant climate fluctuations in the Arctic over the recent past, and additional predicted future temperature changes, highlight the need for high-resolution Arctic paleoclimate records. Arctic coastal environments supplied with terrigenous sediment from Arctic rivers have the potential to provide annual to subdecadal resolution records of climate variability over the last few millennia. A potential tool for paleotemperature reconstructions in these marine sediments is the revised methylation index of branched tetraethers (MBT')/cyclization ratio of branched tetraethers (CBT) proxy based on branched glycerol dialkyl glycerol tetraethers (brGDGTs). In this study, we examine the source of brGDGTs in the Colville River, Alaska, and the adjacent Simpson Lagoon and reconstruct temperatures from Simpson Lagoon sediments to evaluate the applicability of this proxy in Arctic estuarine environments. The Colville catchment soils, fluvial sediments, and estuarine sediments contain statistically similar brGDGT distributions, indicating that the brGDGTs throughout the system are soil derived with little alteration from in situ brGDGT production in the river or coastal waters. Temperatures reconstructed from the MBT'/CBT indices for surface samples show good agreement with regional summer (June through September) temperatures, suggesting a seasonal bias in Arctic temperature reconstructions from the Colville system. In addition, we reconstruct paleotemperatures from an estuarine sediment core that spans the last 75 years, revealing an overall warming trend in the twentieth century that is consistent with trends observed in regional instrumental records. These results support the application of this brGDGT-based paleotemperature proxy for subdecadal-scale summer temperature reconstructions in Arctic estuaries containing organic material derived from sediment-laden, episodic rivers.

  19. 30 CFR 250.220 - If I propose activities in the Alaska OCS Region, what planning information must accompany the EP?

    Science.gov (United States)

    2010-07-01

    ... Region, what planning information must accompany the EP? 250.220 Section 250.220 Mineral Resources... activities in the Alaska OCS Region, what planning information must accompany the EP? If you propose exploration activities in the Alaska OCS Region, the following planning information must accompany your EP: (a...

  20. Estimating regional-scale methane flux and budgets using CARVE aircraft measurements over Alaska

    Directory of Open Access Journals (Sweden)

    S. Hartery

    2018-01-01

    Full Text Available Methane (CH4 is the second most important greenhouse gas but its emissions from northern regions are still poorly constrained. In this study, we analyze a subset of in situ CH4 aircraft observations made over Alaska during the growing seasons of 2012–2014 as part of the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE. Net surface CH4 fluxes are estimated using a Lagrangian particle dispersion model which quantitatively links surface emissions from Alaska and the western Yukon with observations of enhanced CH4 in the mixed layer. We estimate that between May and September, net CH4 emissions from the region of interest were 2.2 ± 0.5 Tg, 1.9 ± 0.4 Tg, and 2.3 ± 0.6 Tg of CH4 for 2012, 2013, and 2014, respectively. If emissions are only attributed to two biogenic eco-regions within our domain, then tundra regions were the predominant source, accounting for over half of the overall budget despite only representing 18 % of the total surface area. Boreal regions, which cover a large part of the study region, accounted for the remainder of the emissions. Simple multiple linear regression analysis revealed that, overall, CH4 fluxes were largely driven by soil temperature and elevation. In regions specifically dominated by wetlands, soil temperature and moisture at 10 cm depth were important explanatory variables while in regions that were not wetlands, soil temperature and moisture at 40 cm depth were more important, suggesting deeper methanogenesis in drier soils. Although similar environmental drivers have been found in the past to control CH4 emissions at local scales, this study shows that they can be used to generate a statistical model to estimate the regional-scale net CH4 budget.

  1. Estimating regional-scale methane flux and budgets using CARVE aircraft measurements over Alaska

    Science.gov (United States)

    Hartery, Sean; Commane, Róisín; Lindaas, Jakob; Sweeney, Colm; Henderson, John; Mountain, Marikate; Steiner, Nicholas; McDonald, Kyle; Dinardo, Steven J.; Miller, Charles E.; Wofsy, Steven C.; Chang, Rachel Y.-W.

    2018-01-01

    Methane (CH4) is the second most important greenhouse gas but its emissions from northern regions are still poorly constrained. In this study, we analyze a subset of in situ CH4 aircraft observations made over Alaska during the growing seasons of 2012-2014 as part of the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE). Net surface CH4 fluxes are estimated using a Lagrangian particle dispersion model which quantitatively links surface emissions from Alaska and the western Yukon with observations of enhanced CH4 in the mixed layer. We estimate that between May and September, net CH4 emissions from the region of interest were 2.2 ± 0.5 Tg, 1.9 ± 0.4 Tg, and 2.3 ± 0.6 Tg of CH4 for 2012, 2013, and 2014, respectively. If emissions are only attributed to two biogenic eco-regions within our domain, then tundra regions were the predominant source, accounting for over half of the overall budget despite only representing 18 % of the total surface area. Boreal regions, which cover a large part of the study region, accounted for the remainder of the emissions. Simple multiple linear regression analysis revealed that, overall, CH4 fluxes were largely driven by soil temperature and elevation. In regions specifically dominated by wetlands, soil temperature and moisture at 10 cm depth were important explanatory variables while in regions that were not wetlands, soil temperature and moisture at 40 cm depth were more important, suggesting deeper methanogenesis in drier soils. Although similar environmental drivers have been found in the past to control CH4 emissions at local scales, this study shows that they can be used to generate a statistical model to estimate the regional-scale net CH4 budget.

  2. Late Quaternary paleoenvironmental records from the Chatanika River valley near Fairbanks (Alaska)

    Science.gov (United States)

    Schirrmeister, Lutz; Meyer, Hanno; Andreev, Andrei; Wetterich, Sebastian; Kienast, Frank; Bobrov, Anatoly; Fuchs, Margret; Sierralta, Melanie; Herzschuh, Ulrike

    2016-09-01

    Perennially-frozen deposits are considered as excellent paleoenvironmental archives similar to lacustrine, deep marine, and glacier records because of the long-term and good preservation of fossil records under stable permafrost conditions. A permafrost tunnel in the Vault Creek Valley (Chatanika River Valley, near Fairbanks) exposes a sequence of frozen deposits and ground ice that provides a comprehensive set of proxies to reconstruct the late Quaternary environmental history of Interior Alaska. The multi-proxy approach includes different dating techniques (radiocarbon-accelerator mass spectrometry [AMS 14C], optically stimulated luminescence [OSL], thorium/uranium radioisotope disequilibria [230Th/U]), as well as methods of sedimentology, paleoecology, hydrochemistry, and stable isotope geochemistry of ground ice. The studied sequence consists of 36-m-thick late Quaternary deposits above schistose bedrock. Main portions of the sequence accumulated during the early and middle Wisconsin periods. The lowermost unit A consists of about 9-m-thick ice-bonded fluvial gravels with sand and peat lenses. A late Sangamon (MIS 5a) age of unit A is assumed. Spruce forest with birch, larch, and some shrubby alder dominated the vegetation. High presence of Sphagnum spores and Cyperaceae pollen points to mires in the Vault Creek Valley. The overlying unit B consists of 10-m-thick alternating fluvial gravels, loess-like silt, and sand layers, penetrated by small ice wedges. OSL dates support a stadial early Wisconsin (MIS 4) age of unit B. Pollen and plant macrofossil data point to spruce forests with some birch interspersed with wetlands around the site. The following unit C is composed of 15-m-thick ice-rich loess-like and organic-rich silt with fossil bones and large ice wedges. Unit C formed during the interstadial mid-Wisconsin (MIS 3) and stadial late Wisconsin (MIS 2) as indicated by radiocarbon ages. Post-depositional slope processes significantly deformed both, ground

  3. Bank storage buffers rivers from saline regional groundwater: an example from the Avon River Australia

    Science.gov (United States)

    Gilfedder, Benjamin; Hofmann, Harald; Cartwrighta, Ian

    2014-05-01

    Groundwater-surface water interactions are often conceptually and numerically modeled as a two component system: a groundwater system connected to a stream, river or lake. However, transient storage zones such as hyporheic exchange, bank storage, parafluvial flow and flood plain storage complicate the two component model by delaying the release of flood water from the catchment. Bank storage occurs when high river levels associated with flood water reverses the hydraulic gradient between surface water and groundwater. River water flows into the riparian zone, where it is stored until the flood water recede. The water held in the banks then drains back into the river over time scales ranging from days to months as the hydraulic gradient returns to pre-flood levels. If the frequency and amplitude of flood events is high enough, water held in bank storage can potentially perpetually remain between the regional groundwater system and the river. In this work we focus on the role of bank storage in buffering river salinity levels against saline regional groundwater on lowland sections of the Avon River, Victoria, Australia. We hypothesize that the frequency and magnitude of floods will strongly influence the salinity of the stream water as banks fill and drain. A bore transect (5 bores) was installed perpendicular to the river and were instrumented with head and electrical conductivity loggers measuring for two years. We also installed a continuous 222Rn system in one bore. This data was augmented with long-term monthly EC from the river. During high rainfall events very fresh flood waters from the headwaters infiltrated into the gravel river banks leading to a dilution in EC and 222Rn in the bores. Following the events the fresh water drained back into the river as head gradients reversed. However the bank water salinities remained ~10x lower than regional groundwater levels during most of the time series, and only slightly above river water. During 2012 SE Australia

  4. Natural versus anthropogenic dispersion of metals to the environment in the Wulik River area, western Brooks Range, northern Alaska

    Science.gov (United States)

    Kelley, K.D.; Hudson, T.

    2007-01-01

    Zinc-lead-silver mineral deposits in the Wulik River region, Alaska, contain an enormous accumulation of Zn. In addition to the giant deposits at Red Dog, at least nine other deposits are known. Natural weathering of these deposits has dispersed metals over a wide region over a long period of time (c. 10 000 years) through transport by stream and groundwater, stream sediments, formation of soils, and perhaps wind-blown atmospheric deposition from weathering of naturally enriched Pb-Zn surface deposits. Anthropogenic input also contributes metals to the environment. Mining of the Red Dog deposit, which began in 1989, produces fine-grained galena and sphalerite concentrates that are transported from the mine site by truck to a storage port facility. Wind-blown dispersion of concentrate dust along the road and around the port facility has been a source of local metal-rich surficial materials. Geochemical and mineralogical characteristics provide a means of distinguishing the natural versus anthropogenic metal sources. Soils over deposits have patterns of increasing metal contents with depth and proximity to the metal-bearing source, whereas ore concentrate dust is localized at the surface. The acidity produced by weathering of the sulphide deposits creates an environment in which elements such as Se and Mo are stable whereas Ca is not. Consequently, high Mo (up to 29 ppm) and Se (up to 17 ppm) and low Ca (<0.4%) concentrations characterize surficial materials near natural deposits. Acidic conditions also yield high Pb-Zn ratios (up to 70) because sphalerite is preferentially dissolved and Zn is mobilized during chemical weathering. In natural materials, secondary jarosite and anglesite are developed, and minor galena is etched and rounded due to a history of chemical and mechanical weathering. In contrast, dust-bearing samples have Pb/Zn ratios that are 0.4 or less, Ca contents are higher (0.2 to 3.6%), and Mo (<10 ppm) and Se (not detected) concentrations are low

  5. The influence of fall-spawning coho salmon (Oncorhynchus kisutch) on growth and production of juvenile coho salmon rearing in beaver ponds on the Copper River Delta, Alaska.

    Science.gov (United States)

    Dirk W. Lang; Gordon H. Reeves; James D. Hall; Mark S. Wipfli

    2006-01-01

    This study examined the influence of fall-spawning coho salmon (Oncorhynchrcs kisutch) on the density, growth rate, body condition, and survival to outmigration of juvenile coho salmon on the Copper River Delta, Alaska, USA. During the fall of 1999 and 2000, fish rearing in beaver ponds that received spawning salmon were compared with fish from...

  6. 78 FR 900 - Approval and Promulgation of Air Quality Implementation Plans; Alaska: Eagle River PM10

    Science.gov (United States)

    2013-01-07

    ... nonattainment area (Eagle River NAA) and the State's request to redesignate the area to attainment for the... NAAQS B. Eagle River NAA and Planning Background III. Requirements for Redesignation A. CAA Requirements... and LMPs A. Has the Eagle River NAA attained the applicable NAAQS? B. Does the Eagle River NAA have a...

  7. Hydrology and morphology of two river mouth regions (temperate Vistula Delta and subtropical Red River Delta

    Directory of Open Access Journals (Sweden)

    Zbigniew Pruszak

    2005-09-01

    Full Text Available The paper presents a comparative analysis of two different river mouths from two different geographical zones (subtropical and temperate climatic regions. One is the multi-branch and multi-spit mouth of the Red River on the Gulf of Tonkin (Vietnam, the other is the smaller delta of the river Vistula on a bay of the Baltic Sea (Poland. The analysis focuses on the similarities and differences in the hydrodynamics between these estuaries and the adjacent coastal zones, the features of sediment transport, and the long-term morphodynamics of the river outlets. Salinity and water level are also discussed, the latter also in the context of the anticipated global effect of accelerated sea level rise. The analysis shows that the climatic and environmental conditions associated with geographical zones give rise to fundamental differences in the generation and dynamic evolution of the river mouths.

  8. Hindcast storm events in the Bering Sea for the St. Lawrence Island and Unalakleet Regions, Alaska

    Science.gov (United States)

    Erikson, Li H.; McCall, Robert T.; van Rooijen, Arnold; Norris, Benjamin

    2015-01-01

    This study provides viable estimates of historical storm-induced water levels in the coastal communities of Gambell and Savoonga situated on St. Lawrence Island in the Bering Sea, as well as Unalakleet located at the head of Norton Sound on the western coast of Alaska. Gambell, Savoonga, and Unalakleet are small Native Villages that are regularly impacted by coastal storms but where little quantitative information about these storms exists. The closest continuous water-level gauge is at Nome, located more than 200 kilometers from both St. Lawrence Island and Unalakleet. In this study, storms are identified and quantified using historical atmospheric and sea-ice data and then used as boundary conditions for a suite of numerical models. The work includes storm-surge (temporary rise in water levels due to persistent strong winds and low atmospheric pressures) modeling in the Bering Strait region, as well as modeling of wave runup along specified sections of the coast in Gambell and Unalakleet. Modeled historical water levels are used to develop return periods of storm surge and storm surge plus wave runup at key locations in each community. It is anticipated that the results will fill some of the data void regarding coastal flood data in western Alaska and be used for production of coastal vulnerability maps and community planning efforts.

  9. Causes of environmental change in the Alligator Rivers region

    International Nuclear Information System (INIS)

    Skidmore, J.

    1990-01-01

    Covering some 28,000 square kilometres of the Northern Territory, the Alligator Rivers Region (ARR) includes the catchments of the East, South and West Alligator Rivers, and many small abandoned uranium mines. To introduce the problems of human impact on the ARR, the toxicologically significant aspects of the local environment were first examined, then the possible effects on it of mining and other human activities. It was found that the most deleterious impact on the region is not caused by mining but by human settlement, introduction of animals (notably the buffalo) and plants, the use of fire and tourism

  10. Gap winds and their effects on regional oceanography Part II: Kodiak Island, Alaska

    Science.gov (United States)

    Ladd, Carol; Cheng, Wei; Salo, Sigrid

    2016-10-01

    Frequent gap winds, defined here as offshore-directed flow channeled through mountain gaps, have been observed near Kodiak Island in the Gulf of Alaska (GOA). Gap winds from the Iliamna Lake gap were investigated using QuikSCAT wind data. The influence of these wind events on the regional ocean was examined using satellite and in situ data combined with Regional Ocean Modeling System (ROMS) model runs. Gap winds influence the entire shelf width (> 200 km) northeast of Kodiak Island and extend an additional 150 km off-shelf. Due to strong gradients in the along-shelf direction, they can result in vertical velocities in the ocean of over 20 m d-1 due to Ekman pumping. The wind events also disrupt flow of the Alaska Coastal Current (ACC), resulting in decreased flow down Shelikof Strait and increased velocities on the outer shelf. This disruption of the ACC has implications for freshwater transport into the Bering Sea. The oceanographic response to gap winds may influence the survival of larval fishes as Arrowtooth Flounder recruitment is negatively correlated with the interannual frequency of gap-wind events, and Pacific Cod recruitment is positively correlated. The frequency of offshore directed winds exhibits a strong seasonal cycle averaging 7 days per month during winter and 2 days per month during summer. Interannual variability is correlated with the Pacific North America Index and shows a linear trend, increasing by 1.35 days per year. An accompanying paper discusses part I of our study (Ladd and Cheng, 2016) focusing on gap-wind events flowing out of Cross Sound in the eastern GOA.

  11. Alligator Rivers Regions Research Institute research report 1983-84

    International Nuclear Information System (INIS)

    1984-01-01

    The Institute undertakes and coordinates research required to ensure the protection of the environment in the Alligator Rivers Region from any consequences resulting from the mining and processing of uranium ore. Research projects outlined are in aquatic biology, terrestrial ecology, analytical chemistry, environmental radioactivity and geomorphology

  12. Application of the multi-dimensional surface water modeling system at Bridge 339, Copper River Highway, Alaska

    Science.gov (United States)

    Brabets, Timothy P.; Conaway, Jeffrey S.

    2009-01-01

    The Copper River Basin, the sixth largest watershed in Alaska, drains an area of 24,200 square miles. This large, glacier-fed river flows across a wide alluvial fan before it enters the Gulf of Alaska. Bridges along the Copper River Highway, which traverses the alluvial fan, have been impacted by channel migration. Due to a major channel change in 2001, Bridge 339 at Mile 36 of the highway has undergone excessive scour, resulting in damage to its abutments and approaches. During the snow- and ice-melt runoff season, which typically extends from mid-May to September, the design discharge for the bridge often is exceeded. The approach channel shifts continuously, and during our study it has shifted back and forth from the left bank to a course along the right bank nearly parallel to the road.Maintenance at Bridge 339 has been costly and will continue to be so if no action is taken. Possible solutions to the scour and erosion problem include (1) constructing a guide bank to redirect flow, (2) dredging approximately 1,000 feet of channel above the bridge to align flow perpendicular to the bridge, and (3) extending the bridge. The USGS Multi-Dimensional Surface Water Modeling System (MD_SWMS) was used to assess these possible solutions. The major limitation of modeling these scenarios was the inability to predict ongoing channel migration. We used a hybrid dataset of surveyed and synthetic bathymetry in the approach channel, which provided the best approximation of this dynamic system. Under existing conditions and at the highest measured discharge and stage of 32,500 ft3/s and 51.08 ft, respectively, the velocities and shear stresses simulated by MD_SWMS indicate scour and erosion will continue. Construction of a 250-foot-long guide bank would not improve conditions because it is not long enough. Dredging a channel upstream of Bridge 339 would help align the flow perpendicular to Bridge 339, but because of the mobility of the channel bed, the dredged channel would

  13. Radioecological monitoring of transboundary rivers of the Central Asian Region

    International Nuclear Information System (INIS)

    Yuldashev, B.S.; Salikhbaev, U.S.; Kist, A.A.; Radyuk, D.S.; Vdovina, E.D.; Zhuk, L.I.

    2005-01-01

    Results of radioecological investigation of Central Asian rivers are presented. Investigation was done as part of the Navruz Project, a cooperative, transboundary river monitoring project involving rivers and institutions in Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan, and facilitated by Sandia National Laboratories in the United States. The study of waterborne radionuclides and metals concentrations in Central Asia is of particular interest because of the history of nuclear materials mining, fabrication, transport, and storage there, when it was part of the Soviet Union. This development left a legacy of radionuclides and metals contamination in some Central Asian regions, which poses a clear health hazard to populations who rely heavily upon surface water for agricultural irrigation and direct domestic consumption. (author)

  14. Southeast Alaska economics: a resource-abundant region competing in a global marketplace.

    Science.gov (United States)

    Lisa K. Crone

    2005-01-01

    Questions related to economics figured prominently in the priority information needs identified in the 1997 Tongass Land Management Plan. Follow-on studies in economics werc designed to improve understanding of aspects of the competitiveness of the Alaska forest sector, links between Alaska timber markets and other markets as evident in prices, and the relationship...

  15. Regional economic impacts of Grand Canyon river runners.

    Science.gov (United States)

    Hjerpe, Evan E; Kim, Yeon-Su

    2007-10-01

    Economic impact analysis (EIA) of outdoor recreation can provide critical social information concerning the utilization of natural resources. Outdoor recreation and other non-consumptive uses of resources are viewed as environmentally friendly alternatives to extractive-type industries. While outdoor recreation can be an appropriate use of resources, it generates both beneficial and adverse socioeconomic impacts on rural communities. The authors used EIA to assess the regional economic impacts of rafting in Grand Canyon National Park. The Grand Canyon region of northern Arizona represents a rural US economy that is highly dependent upon tourism and recreational expenditures. The purpose of this research is twofold. The first is to ascertain the previously unknown regional economic impacts of Grand Canyon river runners. The second purpose is to examine attributes of these economic impacts in terms of regional multipliers, leakage, and types of employment created. Most of the literature on economic impacts of outdoor recreation has focused strictly on the positive economic impacts, failing to illuminate the coinciding adverse and constraining economic impacts. Examining the attributes of economic impacts can highlight deficiencies and constraints that limit the economic benefits of recreation and tourism. Regional expenditure information was obtained by surveying non-commercial boaters and commercial outfitters. The authors used IMPLAN input-output modeling to assess direct, indirect, and induced effects of Grand Canyon river runners. Multipliers were calculated for output, employment, and income. Over 22,000 people rafted on the Colorado River through Grand Canyon National Park in 2001, resulting in an estimated $21,100,000 of regional expenditures to the greater Grand Canyon economy. However, over 50% of all rafting-related expenditures were not captured by the regional economy and many of the jobs created by the rafting industry are lower-wage and seasonal. Policy

  16. The Alaska Water Isotope Network (AKWIN): Precipitation, lake, river and stream dynamics

    Science.gov (United States)

    Rogers, M.; Welker, J. M.; Toohey, R.

    2011-12-01

    The hydrologic cycle is central to the structure and function of northern landscapes. The movement of water creates interactions between terrestrial, aquatic, marine and atmospheric processes. Understanding the processes and the spatial patterns that govern the isotopic (δ18O & δD) characteristics of the hydrologic cycle is especially important today as: a) modern climate/weather-isotope relations allow for more accurate interpretation of climate proxies and the calibration of atmospheric models, b) water isotopes facilitate understanding the role of storm tracks in regulating precipitation isotopic variability, c) water isotopes allow for estimates of glacial melt water inputs into aquatic systems, d) water isotopes allow for quantification of surface and groundwater interactions, e) water isotopes allow for quantification of permafrost meltwater use by plant communities, f) water isotopes aid in migratory bird forensics, g) water isotopes are critical to estimating field metabolic rates, h) water isotopes allow for crop and diet forensics and i) water isotopes can provide insight into evaporation and transpiration processes. As part of a new NSF MRI project at the Environment and Natural Resources Institute (ENRI) at the University of Alaska Anchorage and as an extension of the US Network for Isotopes in Precipitation (USNIP); we are forming AKWIN. The network will utilize long-term weekly sampling at Denali National Park and Caribou Poker Creek Watershed (USNIP sites-1989 to present), regular sampling across Alaska involving land management agencies (USGS, NPS, USFWS, EPA), educators, volunteers and citizen scientists, UA extended campuses, individual research projects, opportunistic sampling and published data to construct isoscapes and time series databases and information packages. We will be using a suite of spatial and temporal analysis methods to characterize water isotopes across Alaska and will provide web portals for data products. Our network is

  17. A limnological survey of the Alligator Rivers Region. 1. Diatoms (Bacillariophyceae) of the region

    International Nuclear Information System (INIS)

    Thomas, D.P.

    1983-08-01

    This study was undertaken as part of a study of the algae of the Alligator Rivers Region in general, and of the Magela Creek in particular, to support an investigation into the possible use of native algae as an indicator of any changes in water quality which might occur as a result of uranium mining and milling in the Region

  18. Dietary pathways through lizards of the Alligator Rivers Region

    International Nuclear Information System (INIS)

    James, C.D.; Morton, S.R.; Braithwaite, R.W.; Wombey, J.C.

    1984-07-01

    A broad survey of the diets of 46 species of terrestrial and arboreal lizards from the families Gekkonidae, Pygopodidae, Agamidae and Scincidae was carried out in the Alligator Rivers Region, and the diets of three of the species were examined in detail by monthly sampling near the Ranger uranium mine. The study shows that, in the event of contamination of the waterbodies, only two species of lizards face any risk of contamination through their food

  19. Plants of the Alligator Rivers Region, Northern Territory

    International Nuclear Information System (INIS)

    Cowie, I.D.; Finlayson, C.M.

    1986-01-01

    Published and unpublished lists of plants of the Alligator Rivers Region have been combined into a single, up-to-date check-list. The list has been designed to replace fragmented, regional listings with a single document suitable for use by both professional and amateur botanists. The list is ordered in the taxonomic sequence adopted for the Flora of Australia and includes 1346 species from 165 families. These are 1275 native and 71 alien species listed. Separate lists of rare species are given and discussed

  20. Plants of the Alligator Rivers Region, Northern Territory

    Energy Technology Data Exchange (ETDEWEB)

    Cowie, I D; Finlayson, C M

    1986-01-01

    Published and unpublished lists of plants of the Alligator Rivers Region have been combined into a single, up-to-date check-list. The list has been designed to replace fragmented, regional listings with a single document suitable for use by both professional and amateur botanists. The list is ordered in the taxonomic sequence adopted for the Flora of Australia and includes 1346 species from 165 families. These are 1275 native and 71 alien species listed. Separate lists of rare species are given and discussed.

  1. Regional seismic lines reprocessed using post-stack processing techniques; National Petroleum Reserve, Alaska

    Science.gov (United States)

    Miller, John J.; Agena, W.F.; Lee, M.W.; Zihlman, F.N.; Grow, J.A.; Taylor, D.J.; Killgore, Michele; Oliver, H.L.

    2000-01-01

    This CD-ROM contains stacked, migrated, 2-Dimensional seismic reflection data and associated support information for 22 regional seismic lines (3,470 line-miles) recorded in the National Petroleum Reserve ? Alaska (NPRA) from 1974 through 1981. Together, these lines constitute about one-quarter of the seismic data collected as part of the Federal Government?s program to evaluate the petroleum potential of the Reserve. The regional lines, which form a grid covering the entire NPRA, were created by combining various individual lines recorded in different years using different recording parameters. These data were reprocessed by the USGS using modern, post-stack processing techniques, to create a data set suitable for interpretation on interactive seismic interpretation computer workstations. Reprocessing was done in support of ongoing petroleum resource studies by the USGS Energy Program. The CD-ROM contains the following files: 1) 22 files containing the digital seismic data in standard, SEG-Y format; 2) 1 file containing navigation data for the 22 lines in standard SEG-P1 format; 3) 22 small scale graphic images of each seismic line in Adobe Acrobat? PDF format; 4) a graphic image of the location map, generated from the navigation file, with hyperlinks to the graphic images of the seismic lines; 5) an ASCII text file with cross-reference information for relating the sequential trace numbers on each regional line to the line number and shotpoint number of the original component lines; and 6) an explanation of the processing used to create the final seismic sections (this document). The SEG-Y format seismic files and SEG-P1 format navigation file contain all the information necessary for loading the data onto a seismic interpretation workstation.

  2. Feasibility analysis of a smart grid photovoltaics system for the subarctic rural region in Alaska

    Science.gov (United States)

    Yao, Lei

    A smart grid photovoltaics system was developed to demonstrate that the system is feasible for a similar off-grid rural community in the subarctic region in Alaska. A system generation algorithm and a system business model were developed to determine feasibility. Based on forecasts by the PV F-Chart software, a 70° tilt angle in winter, and a 34° tilt angle in summer were determined to be the best angles for electrical output. The proposed system's electricity unit cost was calculated at 32.3 cents/kWh that is cheaper than current unsubsidized electricity price (46.8 cents/kWh) in off-grid rural communities. Given 46.8 cents/kWh as the electricity unit price, the system provider can break even when 17.3 percent of the total electrical revenue through power generated by the proposed system is charged. Given these results, the system can be economically feasible during the life-cycle period. With further incentives, the system may have a competitive advantage.

  3. 76 FR 21404 - National Park Service Alaska Region's Subsistence Resource Commission (SRC) Program

    Science.gov (United States)

    2011-04-15

    ... National Park SRC will meet at the Shungnak Public School, 907-437-2151, in Shungnak, Alaska on Wednesday... changed, a notice will be published in local newspapers and announced on local radio stations prior to the...

  4. Genetic investigation of natural hybridization between rainbow and coastal cutthroat trout in the copper River Delta, Alaska

    Science.gov (United States)

    Williams, I.; Reeves, G.H.; Graziano, S.L.; Nielsen, J.L.

    2007-01-01

    Molecular genetic methods were used to quantify natural hybridization between rainbow trout Oncorhynchus mykiss or steelhead (anadromous rainbow trout) and coastal cutthroat trout O. clarkii clarkii collected in the Copper River delta, Southeast Alaska. Eleven locations were sampled to determine the extent of hybridization and the distribution of hybrids. Four diagnostic nuclear microsatellite loci and four species-specific simple sequence repeat markers were used in combination with restriction fragment length polymorphism analyses of NADH dehydrogenase 5/6 (ND5/6) mitochondrial DNA (mtDNA) to investigate the genetic structure of trout from both species and identify putative interspecific hybrids. Hybrids were found in 7 of the 11 streams sampled in the Copper River delta, the extent of hybridization across all streams varying from 0% to 58%. Hybrid trout distribution appeared to be nonrandom, most individuals of mixed taxonomic ancestry being detected in streams containing rainbow trout rather than in streams containing coastal cutthroat trout. Genotypic disequilibrium was observed among microsatellite loci in populations with high levels of hybridization. We found no significant correlation between unique stream channel process groups and the number of hybrid fish sampled. Eighty-eight percent of fish identified as first-generation hybrids (F1) in two populations contained coastal cutthroat trout mtDNA, suggesting directionality in hybridization. However, dominance of coastal cutthroat trout mtDNA was not observed at a third location containing F1 hybrids, indicating that interspecific mating behavior varied among locations. Backcrossed individuals were found in drainages lacking F1 hybrids and in populations previously thought to contain a single species. The extent and distribution of backcrossed individuals suggested that at least some hybrids are reproductively viable and backcrossed hybrid offspring move throughout the system.

  5. Stratigraphy and Facies of Cretaceous Schrader Bluff and Prince Creek Formations in Colville River Bluffs, North Slope, Alaska

    Science.gov (United States)

    Flores, Romeo M.; Myers, Mark D.; Houseknecht, David W.; Stricker, Gary D.; Brizzolara, Donald W.; Ryherd, Timothy J.; Takahashi, Kenneth I.

    2007-01-01

    Stratigraphic and sedimentologic studies of facies of the Upper Cretaceous rocks along the Colville River Bluffs in the west-central North Slope of Alaska identified barrier shoreface deposits consisting of vertically stacked, coarsening-upward parasequences in the Schrader Bluff Formation. This vertical stack of parasequence deposits represents progradational sequences that were affected by shoaling and deepening cycles caused by fluctuations of sea level. Further, the vertical stack may have served to stabilize accumulation of voluminous coal deposits in the Prince Creek Formation, which formed braided, high-sinuosity meandering, anastomosed, and low-sinuosity meandering fluvial channels and related flood plain deposits. The erosional contact at the top of the uppermost coarsening-upward sequence, however, suggests a significant drop of base level (relative sea level) that permitted a semiregional subaerial unconformity to develop at the contact between the Schrader Bluff and Prince Creek Formations. This drop of relative sea level may have been followed by a relative sea-level rise to accommodate coal deposition directly above the unconformity. This rise was followed by a second drop of relative sea level, with formation of incised valley topography as much as 75 ft deep and an equivalent surface of a major marine erosion or mass wasting, or both, either of which can be traced from the Colville River Bluffs basinward to the subsurface in the west-central North Slope. The Prince Creek fluvial deposits represent late Campanian to late Maastrichtian depositional environments that were affected by these base level changes influenced by tectonism, basin subsidence, and sea-level fluctuations.

  6. Changes in diets of river otters in Prince William Sound, Alaska: Effects of the Exxon Valdez oil spill

    International Nuclear Information System (INIS)

    Bowyer, R.T.; Testa, J.W.; Faro, J.B.; Schwartz, C.C.; Browning, J.B.

    1994-01-01

    The effects of the Exxon Valdez oil spill on the diets of river otters (Lutra canadensis) from oiled and nonoiled areas of Prince William Sound, Alaska, were examined in 1989 and 1990. On the basis of identification of prey remains in their feces, otters fed principally on marine, bottom-dwelling fishes. Marine gastropods, bivalves, and crustaceans composed most of the invertebrates in the diet of otters; freshwater and terrestrial food items seldom occurred in their feces. The diets of otters included 149 different taxa, most of which rarely occurred in their feces. Sixty-five taxa occurred ≥5 times in the combined data set. Species richness and diversity of prey remains in otter feces were similar on oiled and nonoiled study areas in late winter 1989 (before the oil spill) and during summer 1989 following the spill. By summer 1990, however, there were significant declines in the richness and diversity of species (mostly bony fish, molluscs, and bivalves) in otter diets on the oiled area. Likewise, the relative abundance of prey remains in otter feces showed strong differences between areas and years, and an area by year interaction. Members of the Perciformes and Archaeogastropoda declined from 1989 to 1990 on the oiled area while they increased on the nonoiled site; Malacostraca exhibited the opposite pattern. These outcomes, when considered with other data on body mass and blood chemistry, strongly suggest that some effects of the oil spill on otters were delayed. 14 refs., 6 figs., 1 tab

  7. Oceanographic studies in Harrison Bay and the Colville River Delta, Alaska, to support the development of oil spill response strategies

    International Nuclear Information System (INIS)

    Owens, E.H.; Taylor, E.; Hale, B.

    2003-01-01

    The risk of an oil spill resulting from the development of the Alpine oil field is considered to be low. The field is located on the North Slope of Alaska adjacent to the Alaskan Beaufort Sea and reaches coastal waters from the distributary channels of the Colville River Delta. The physical environmental (hydrodynamic) conditions that would affect the transport and fate of spilled oil was investigated to further reduce the risk. During the open-water season of 2001 in Harrison Bay, near shore current meters were deployed and data on weather and surface currents was analyzed. Ocean current and wind measurements were examined to evaluate the relationship between meteorology and water levels during the open-water season. The objective was to gain a better understanding of the near shore hydrodynamic processes at play in Harrison Bay, in order to plan the most appropriate spill response strategies. The results obtained indicate that surface currents within the bay adjacent to the Colville Delta are variable. They respond to wind forces as well as other possible mechanisms like estuarine circulation. The surface currents reach maximum speeds of 0.26 metre per second. For the late July-September deployment, the calculated net surface drift was a 0.02 metre per second current to the east southeast. In both Harrison Bay and Colville Delta, prevailing southwest and northeast winds, respectively, induced water level changes of more than 0.5 metre above and below the average. 7 refs., 3 tabs., 7 figs

  8. Rainbow trout movement behavior and habitat occupancy are influenced by sex and Pacific salmon presence in an Alaska river system

    Science.gov (United States)

    Fraley, Kevin M.; Falke, Jeffrey A.; McPhee, Megan V.; Prakash, Anupma

    2018-01-01

    We used spatially continuous field-measured and remotely-sensed aquatic habitat characteristics paired with weekly ground-based telemetry tracking and snorkel surveys to describe movements and habitat occupancy of adult rainbow trout (N = 82) in a runoff-fed, salmon-influenced southcentral Alaska river system. We found that during the ice-free feeding season (June through September) rainbow trout occurrence was associated more with fine-scale (channel unit) characteristics relative to coarse-scale (stream reach) variables. The presence of Pacific salmon (which provide an important seasonal food subsidy), and habitat size were particularly useful predictors. Weekly movement distance differed between pre- and post- spawning salmon arrival, but did not vary by sex. Habitat quality, season, and the arrival of spawning salmon influenced the likelihood of rainbow trout movement, and fish moved farther to seek out higher quality habitats. Because rainbow trout respond to habitat factors at multiple scales and seek out salmon-derived subsidies, it will be important to take a multiscale approach in protecting trout and salmon populations and managing the associated fisheries.

  9. Geochemistry of waters in the Valley of Ten Thousand Smokes region, Alaska

    Science.gov (United States)

    Keith, T.E.C.; Thompson, J.M.; Hutchinson, R.A.; White, L.D.

    1992-01-01

    Meteoric waters from cold springs and streams outside of the 1912 eruptive deposits filling the Valley of Ten Thousand Smokes (VTTS) and in the upper parts of the two major rivers draining the 1912 deposits have similar chemical trends. Thermal springs issue in the mid-valley area along a 300-m lateral section of ash-flow tuff, and range in temperature from 21 to 29.8??C in early summer and from 15 to 17??C in mid-summer. Concentrations of major and minor chemical constituents in the thermal waters are nearly identical regardless of temperature. Waters in the downvalley parts of the rivers draining the 1912 deposits are mainly mixtures of cold meteoric waters and thermal waters of which the mid-valley thermal spring waters are representative. The weathering reactions of cold waters with the 1912 deposits appear to have stabilized and add only subordinate amounts of chemical constituents to the rivers relative to those contributed by the thermal waters. Isotopic data indicate that the mid-valley thermal spring waters are meteoric, but data is inconclusive regarding the heat source. The thermal waters could be either from a shallow part of a hydrothermal system beneath the 1912 vent region or from an incompletely cooled, welded tuff lens deep in the 1912 ash-flow sheet of the upper River Lethe area. Bicarbonate-sulfate waters resulting from interaction of near-surface waters and the cooling 1953-1968 southwest Trident plug issue from thermal springs south of Katmai Pass and near Mageik Creek, although the Mageik Creek spring waters are from a well-established, more deeply circulating hydrothermal system. Katmai caldera lake waters are a result of acid gases from vigorous drowned fumaroles dissolving in lake waters composed of snowmelt and precipitation. ?? 1992.

  10. Alaska's indigenous muskoxen: a history

    Directory of Open Access Journals (Sweden)

    Peter C. Lent

    1998-03-01

    Full Text Available Muskoxen (Ovibos moschatus were widespread in northern and interior Alaska in the late Pleistocene but were never a dominant component of large mammal faunas. After the end of the Pleistocene they were even less common. Most skeletal finds have come from the Arctic Coastal Plain and the foothills of the Brooks Range. Archaeological evidence, mainly from the Point Barrow area, suggests that humans sporadically hunted small numbers of muskoxen over about 1500 years from early Birnirk culture to nineteenth century Thule culture. Skeletal remains found near Kivalina represent the most southerly Holocene record for muskoxen in Alaska. Claims that muskoxen survived into the early nineteenth century farther south in the Selawik - Buckland River region are not substantiated. Remains of muskox found by Beechey's party in Eschscholtz Bay in 1826 were almost certainly of Pleistocene age, not recent. Neither the introduction of firearms nor overwintering whalers played a significant role in the extinction of Alaska's muskoxen. Inuit hunters apparently killed the last muskoxen in northwestern Alaska in the late 1850s. Several accounts suggest that remnant herds survived in the eastern Brooks Range into the 1890s. However, there is no physical evidence or independent confirmation of these reports. Oral traditions regarding muskoxen survived among the Nunamiut and the Chandalar Kutchin. With human help, muskoxen have successfully recolonized their former range from the Seward Peninsula north, across the Arctic Slope and east into the northern Yukon Territory.

  11. Regional lead isotope study of a polluted river catchment: River Wear, Northern England, UK

    International Nuclear Information System (INIS)

    Shepherd, Thomas J.; Chenery, Simon R.N.; Pashley, Vanessa; Lord, Richard A.; Ander, Louise E.; Breward, Neil; Hobbs, Susan F.; Horstwood, Matthew; Klinck, Benjamin A.; Worrall, Fred

    2009-01-01

    High precision, lead isotope analyses of archived stream sediments from the River Wear catchment, northeast England (1986-88), provide evidence for three main sources of anthropogenic lead pollution; lead mining, industrial lead emissions and leaded petrol. In the upper catchment, pollution is totally controlled and dominated by large lead discharges from historic mining centres in the North Pennine Orefield ( 208 Pb/ 206 Pb, 207 Pb/ 206 Pb ratios range from 2.0744-2.0954 and 0.8413-0.8554 respectively). In the lower catchment, co-extensive with the Durham Coalfield and areas of high population density, pollution levels are lower and regionally more uniform. Isotope ratios are systematically higher than in the upper catchment ( 208 Pb/ 206 Pb, 207 Pb/ 206 Pb ratios range from 2.0856-2.1397 and 0.8554-0.8896 respectively) and far exceed values determined for the geogenic regional background. Here, the pollution is characterised by the atmospheric deposition of industrial lead and petrol lead. Lead derived from the combustion of coal, although present, is masked by the other two sources. Recent sediments from the main channel of the River Wear are isotopically indistinguishable from older, low order stream sediments of the North Pennine Orefield, indicating that contamination of the river by lead mining waste (up to several 1000 mg/kg Pb at some locations) continues to pose an environmental problem; a pattern that can be traced all the way to the tidal reach. Using within-catchment isotope variation and sediment lead concentrations, estimates can be made of the discharges from discrete mines or groups of mines to the overall level of lead pollution in the River Wear. As well as providing information pertinent to source apportionment and on-going catchment remediation measures, the database is a valuable resource for epidemiologists concerned with the health risks posed by environmental lead.

  12. Regional lead isotope study of a polluted river catchment: River Wear, Northern England, UK

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, Thomas J., E-mail: shepherdtj@aol.com [Department of Earth Sciences, University of Durham, Science Laboratories, Durham DH1 3LE (United Kingdom); Chenery, Simon R.N. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Pashley, Vanessa [NERC Isotope Geosciences Laboratory, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (United Kingdom); Lord, Richard A. [School of Science and Technology, University of Teesside, Middlesbrough, Tees Valley TS1 3BA (United Kingdom); Ander, Louise E.; Breward, Neil; Hobbs, Susan F. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Horstwood, Matthew [NERC Isotope Geosciences Laboratory, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (United Kingdom); Klinck, Benjamin A. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Worrall, Fred [Department of Earth Sciences, University of Durham, Science Laboratories, Durham DH1 3LE (United Kingdom)

    2009-08-15

    High precision, lead isotope analyses of archived stream sediments from the River Wear catchment, northeast England (1986-88), provide evidence for three main sources of anthropogenic lead pollution; lead mining, industrial lead emissions and leaded petrol. In the upper catchment, pollution is totally controlled and dominated by large lead discharges from historic mining centres in the North Pennine Orefield ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios range from 2.0744-2.0954 and 0.8413-0.8554 respectively). In the lower catchment, co-extensive with the Durham Coalfield and areas of high population density, pollution levels are lower and regionally more uniform. Isotope ratios are systematically higher than in the upper catchment ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios range from 2.0856-2.1397 and 0.8554-0.8896 respectively) and far exceed values determined for the geogenic regional background. Here, the pollution is characterised by the atmospheric deposition of industrial lead and petrol lead. Lead derived from the combustion of coal, although present, is masked by the other two sources. Recent sediments from the main channel of the River Wear are isotopically indistinguishable from older, low order stream sediments of the North Pennine Orefield, indicating that contamination of the river by lead mining waste (up to several 1000 mg/kg Pb at some locations) continues to pose an environmental problem; a pattern that can be traced all the way to the tidal reach. Using within-catchment isotope variation and sediment lead concentrations, estimates can be made of the discharges from discrete mines or groups of mines to the overall level of lead pollution in the River Wear. As well as providing information pertinent to source apportionment and on-going catchment remediation measures, the database is a valuable resource for epidemiologists concerned with the health risks posed by environmental lead.

  13. Power to the people - A regional utility's approach in rural Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, William [AVEC Canada (Canada)

    2011-07-01

    Avec is a non-profit firm working in various fields, such as building interties and capturing recovered heat. The aim of this paper is to give an overview of the company's approach in rural Alaska. The state and federal governments funded over 100 wind projects in Alaska in the 1980s and nearly all failed due to lack of maintenance and poor locations. Geographical and technical challenges included, among others, complex logistics, poor soils and low temperatures. Moreover, the availability of heavy construction equipment was key issue. The challenge was to have access to specialty equipment and wind assessment was critical. The geotechnical conditions also presented unique challenges. But there were benefits, like the reduction in carbon footprint and reduced exposure to oil spills. Future plans include evaluation of sites for future funding in several rural areas of western Alaska. Clearly, there are a very great number of challenges involved but the work and results are rewarding.

  14. Tanana River Monitoring and Research Program: Relationships Among Bank Recession, Vegetation, Soils, Sediments and Permafrost on the Tanana River Near Fairbanks, Alaska.

    Science.gov (United States)

    1984-07-01

    influencing bank erosion along the Tanana River. Soils The regional soil association along both reaches is loamy, consisting of nearly level histic pergelic ...conspicuous. Most areas of this association are flooded occasionally. The histic pergelic cryaquepts occur in poorly drained, low areas such as meander...great depth; usually occupy natural levees. 6Histic pergelic cryaquepts: soils with texture ranging from gravelly sand to clay, color from gray to

  15. 30 CFR 250.251 - If I propose activities in the Alaska OCS Region, what planning information must accompany the DPP?

    Science.gov (United States)

    2010-07-01

    ... Region, what planning information must accompany the DPP? 250.251 Section 250.251 Mineral Resources... Region, what planning information must accompany the DPP? If you propose development and production activities in the Alaska OCS Region, the following planning information must accompany your DPP: (a...

  16. Geochemical evidence for the origin of late Quaternary loess in central Alaska

    Science.gov (United States)

    Muhs, D.R.; Budahn, J.R.

    2006-01-01

    Loess is extensive in central Alaska, but there are uncertainties about its source and the direction of paleo-winds that deposited it. Both northerly and southerly winds have been inferred. The most likely sources of loess are the Tanana River (south), the Nenana River (southeast), and the Yukon River (north). Late Quaternary loess in central Alaska has immobile trace-element compositions (Cr/Sc, Th/Ta, Th/ Sc, Th/U, Eu/Eu*, GdN/YbN) that indicate derivation mostly from the Tanana River. However, other ratios (As/Sb, Zr/Hf, LaN/YbN) and quantitative modeling indicate that the Yukon River was also a source. During the last glacial period, there may have been a longer residence time of the Siberian and Canadian high-pressure cells, along with a strengthened Aleutian low-pressure cell. This would have generated regional-scale northeasterly winds and explains derivation of loess from the Yukon River. However, superim-posed upon this synoptic-scale circulation, there may have been strong, southerly katabatic winds from expanded glaciers on the northern flank of the Alaska Range. These winds could have provided eolian silt from the Tanana River. Yukon River and Tanana River sediments are highly calcareous, whereas Fairbanks-area loess is not. This suggests that carbonate leaching in loess kept ahead of sedimentation and that late Quaternary loess in central Alaska was deposited relatively slowly. ?? 2006 NRC Canada.

  17. Off-platform Silurian sequences in the Ambler River quadrangle: A section in Geologic studies in Alaska by the U.S. Geological Survey during 1987

    Science.gov (United States)

    Dumoulin, Julie A.; Harris, Anita G.

    1988-01-01

    Lithofacies changes in coeval upper Paleozoic rocks have been used to unravel the tectonic history of northern Alaska (for example, Mayfield and others, 1983). Conodont biostratigraphy and detailed petrologic studies are now revealing facies differences in lower Paleozoic rocks that can also be used to constrain their tectono-sedimentary framework (Dumoulin and Harris, 1987). A basic element of basin analysis is the discrimination of shallow-water shelf and platform sequences from deeper water slope and basinal deposits. This report documents several new localities of deeper water, off-platform Silurian deposits in the Ambler River quadrangle and briefly outlines some of their paleogeographic implications.

  18. The Alaskan mineral resource assessment program; background information to accompany folio of geologic and mineral resource maps of the Ambler River Quadrangle, Alaska

    Science.gov (United States)

    Mayfield, Charles F.; Tailleur, I.L.; Albert, N.R.; Ellersieck, Inyo; Grybeck, Donald; Hackett, S.W.

    1983-01-01

    The Ambler River quadrangle, consisting of 14,290 km2 (5,520 mi2) in northwest Alaska, was investigated by an interdisciplinary research team for the purpose of assessing the mineral resource potential of the quadrangle. This report provides background information for a folio of maps on the geology, reconnaissance geochemistry, aeromagnetics, Landsat imagery, and mineral resource evaluation of the quadrangle. A summary of the geologic history, radiometric dates, and fossil localities and a comprehensive bibliography are also included. The quadrangle contains jade reserves, now being mined, and potentially significant resources of copper, zinc, lead, and silver.

  19. A Regional Survey of River-plume Sedimentation on the Mississippi River Delta Front

    Science.gov (United States)

    Courtois, A. J.; Bentley, S. J.; Xu, K.; Georgiou, I. Y.; Maloney, J. M.; Miner, M. D.; Chaytor, J. D.; Smith, J.

    2017-12-01

    Many studies of the Mississippi River and Delta (MRD) have shown historic declines in sediment load reaching the main river distributaries over the last few decades. Recent studies also reported that 50% of the suspended load during floods is sequestered within the delta. While the impact of declining sediment load on wetland loss is well documented, submarine sedimentary processes on the delta front during this recent period of declining sediment load are understudied. To better understand modern sediment dispersal and deposition across the Mississippi River Delta Front, 31 multicores were collected in June 2017 from locations extending offshore from Southwest Pass, South Pass, and Pass a Loutre (the main river outlets) in water depths of 25-280 m. Core locations were selected based on multibeam bathymetry and morphology collected by the USGS in May 2017; the timing of collection coincided with the end of annual peak discharge on the Mississippi River. This multi-agency survey is the first to study delta-front sedimentary processes regionally with such a wide suite of tools. Target locations for coring included the dominant depositional environments: mudflow lobes, gullies, and undisturbed prodelta. Cores were subsampled at 2 cm intervals and analyzed for Beryllium-7 activity via gamma spectrometry; in such settings, Be-7 can be used as a tracer of sediment recently delivered from fluvial origin. Results indicate a general trend of declining Be-7 activity with increasing distance from source, and in deeper water. Inshore samples near Southwest Pass show the deepest penetration depth of Be-7 into the sediment (24-26 cm), which is a preliminary indicator of rapid seasonal sedimentation. Nearshore samples from South Pass exhibited similar Be-7 penetration depths, with results near Pass a Loutre to 14-16 cm depth. Be-7 remains detectable to 2 cm in water 206 m deep, approximately 20 km from South Pass. Sediment dispersal remains impressive offshore from all three

  20. Uranium hydrogeochemical and stream-sediment reconnaissance of the Charley River NTMS Quadrangle, Alaska. National Uranium Resource Evaluation

    International Nuclear Information System (INIS)

    1982-08-01

    This report presents results of a Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Charley River NTMS quadrangle, Alaska. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form. These machine-readable data, as well as quarterly or semiannual program progress reports containing further information on the HSSR program in general, or on the Los Alamos National Laboratory (LANL) portion of the program in particular, are available from DOE's Technical Library at its Grand Junction Area Office. Presented in this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume; these data are, however, available on the magnetic tape. Appendices A and B describe the sample media and summarize the analytical results for each medium. The data have been subdivided by one of the Los Alamos National Laboratory sorting programs of Zinkl and others (1981a) into groups of stream-sediment and lake-sediment ground-water samples. For each group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1:1,000,000 scale maps of pertinent elements have been included in this report. Also included are maps showing results of multivariate statistical analyses. Information on the field and analytical procedures used by the Los Alamos National Laboratory during sample collection and analysis may be found in any HSSR data release prepared by the Laboratory and will not be included in this report

  1. Uranium hydrogeochemical and stream sediment reconnaissance of the Kateel River NTMS Quadrangle, Alaska. National Uranium Resource Evaluation

    International Nuclear Information System (INIS)

    Hardy, L.C.; D'Andrea, R.F. Jr.; Zinkl, R.J.

    1982-08-01

    This report presents results of a Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Kateel River NTMS Quadrangle, Alaska. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form. These machine-readable data, as well as quarterly or semiannual program progress reports containing further information on the HSSR program in general, or on the Los Alamos National Laboratory (LANL) portion of the program in particular, are available from DOE's Technical Library at its Grand Junction Area Office. Presented in this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume; these data are, however, available on the magnetic tape. Appendices A and B describe the sample media and summarize the analytical results for each medium. The data have been subdivided by one of the Los Alamos National Laboratory sorting programs of Zinkl and others (1981a) into groups of stream-sediment, lake-sediment, stream-water, lake-water, and ground-water samples. For each group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1:1,000,000 scale maps of pertinent elements have been included in this report. Also included are maps showing results of multivariate statistical analyses. Information on the field and analytical procedures used by the Los Alamos National Laboratory during sample collection and analysis may be found in any HSSR data release prepared by the Laboratory and will not be included in this report

  2. Uranium hydrogeochemical and stream-sediment reconnaissance of the Black River NTMS Quadrangle, Alaska. National Uranium Resource Evaluation

    International Nuclear Information System (INIS)

    1982-08-01

    This report presents results of a Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Black River NTMS quadrangle, Alaska. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form. These machine-readable data, as well as quarterly or semiannual program progress reports containing further information on the HSSR program in general, or on the Los Alamos National Laboratory (LANL) portion of the program in particular, are available from DOE's Technical Library at its Grand Junction Area Office. Presented in this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume; these data are, however, available on the magnetic tape. Appendices A and B describe the sample media and summarize the analytical results for each medium. The data have been subdivided by one of the Los Alamos National Laboratory sorting programs of Zinkl and others (1981a) into groups of stream-sediment and lake-sediment samples. For each group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1:1,000,000 scale maps of pertinent elements have been included in this report. Also included are maps showing results of multivariate statistical analyses. Information on the field and analytical procedures used by the Los Alamos National Laboratory during sample collection and analysis may be found in any HSSR data release prepared by the Laboratory and will not be included in this report

  3. Uranium hydrogeochemical and stream-sediment reconnaissance of the Kantishna River NTMS quadrangle, Alaska. National Uranium Resource Evaluation

    International Nuclear Information System (INIS)

    Hardy, L.C.; D'Andrea, R.F. Jr.; Zinkl, R.J.

    1982-08-01

    This report presents results of a Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Kantishna River NTMS quadrangle, Alaska. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form. These machine-readable data, as well as quarterly or semiannual program progress reports containing further information on the HSSR program in general, or on the Los Alamos National Laboratory (LANL) portion of the program in particular, are available from DOE's Technical Library at its Grand Junction Area Office. Presented in this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume; these data are, however, available on the magnetic tape. Appendices A and B describe the sample media and summarize the analytical results for each medium. The data have been subdivided by one of the Los Alamos National Laboratory sorting programs of Zinkl and others (1981a) into groups of stream-sediment and lake-sediment samples. For each group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1:1,000,000 scale maps of pertinent elements have been included in this report. Also included are maps showing results of multivariate statistical analyses. Information on the field and analytical procedures used by the Los Alamos National Laboratory during sample collection and analysis may be found in any HSSR data release prepared by the Laboratory and will not be included in this report

  4. The Response of Tundra to Biophysical Changes Ten Years Following the Anaktuvuk River Fire, Arctic Foothills, Alaska.

    Science.gov (United States)

    Jones, B. M.; Miller, E. A.; Jandt, R.; Baughman, C. A.

    2017-12-01

    Ten years following a large and severe wildfire in the arctic foothills of the Brooks Range, Alaska, tundra is experiencing rapid biophysical changes. Plant communities are responding to primary disturbance by fire but also to ground-ice melt, terrain subsidence, and apparent increase in soil drainage or evapotranspiration.The Anaktuvuk River Fire burned about 104,000 ha in 2007, spreading over broad ranges in soils, topography, hydrography, and permafrost features. Fourteen marked transects were measured between 2008-2011 and again in 2017 for cover of ground-layer vegetation, tall shrub abundance, thaw depth, and soil properties. A complementary set of 11 reference transects surrounding the burn was also sampled.We observed much higher rates of thermokarst inside the burn than out. Even low severity burn areas experienced noticeable thaw subsidence. Mean annual ground temperature at 1 m depth has warmed 1.5°C relative to unburned tundra. In cases ice wedge troughs have deepened by more than 1 m in areas underlain by yedoma soils. Troughs were characterized by cracking soil and slumping tussocks, often into ponded water. Troughs and degraded ice features appear to be draining adjacent polygon centers leading to a general drying of the tundra. Tussockgrasses inside the burn continue to grow and flower vigorously, suggesting a continued flush of soil nutrients. Post-fire accumulation of organic material is generally fire greatly accelerates this succession. Records and observations suggest that lightning and ignitions are becoming more frequent north of the Brooks Range.Our monitoring of this burn over the last ten years reveals a story much more complicated than our team can tell, inviting involvement of other disciplines, particularly hydrology, soil and landform science, remote sensing, and wildlife and subsistence resource management.

  5. 76 FR 3653 - Alaska Region's Subsistence Resource Commission (SRC) Program; Public Meeting

    Science.gov (United States)

    2011-01-20

    ... subsistence management issues. The NPS SRC program is authorized under Title VIII, Section 808 of the Alaska...: 1. Call to order. 2. SRC Roll Call and Confirmation of Quorum. 3. Welcome and Introductions. 4... Board of Game Update. 12. Old Business. a. Subsistence Uses of Horns, Antlers, Bones and Plants EA...

  6. 78 FR 10546 - Approval and Promulgation of Implementation Plans; State of Alaska; Regional Haze State...

    Science.gov (United States)

    2013-02-14

    ..., 1200 Sixth Avenue, Seattle, WA 98101, (206) 553-1949. SUPPLEMENTARY INFORMATION: Definitions For the... tourism in Alaska, motoring techniques and coal combustion and other generalized concerns or comments... comments urging EPA to preserve the views at Denali National Park, and to ensure that tourism to pristine...

  7. 75 FR 51103 - Notice of Public Meetings for the National Park Service (NPS) Alaska Region's Subsistence...

    Science.gov (United States)

    2010-08-18

    ... SRC and Wrangell-St. Elias SRC plan to meet to develop and continue work on National Park Service (NPS... reconvene on Thursday, October 7, 2010, from 9 a.m. to 5 p.m. or until business is completed. This meeting will be held at Fast Eddy's Motel and Restaurant located at Mile 1313 on the Alaska Highway in Tok, AK...

  8. The Demographics of Travel in the Two Rivers-Ottauquechee Region

    Science.gov (United States)

    2009-02-19

    In March of 2008, the Two Rivers-Ottauquechee Regional Commission (TRORC) contracted with TranSystems, a consulting firm based in Montpelier, to conduct a regional transportation planning study for the region. Called the Demographics of Transportatio...

  9. Climate change impact on the river runoff: regional study for the Central Asian Region

    International Nuclear Information System (INIS)

    Agaitseva, Natalya

    2004-01-01

    increase is expected in evaporation from water surfaces of 15-20%. The most severe and climate conditions in the watershed area were predicted under the CCCM model. According to this model, if CO 2 concentration in the atmosphere is doubled, then the runoffs of the Syrdarya and Amudarya rivers are expected to be reduced by 28 and 40%, respectively. According to GFDL and GISS scenarios, presented.(Author)e experiencethe catchment area would increase by 3-4 o C and average annual precipitation volume by 10-15%. Under these scenarios, one could expect that no significant reduction in the Amudarya and Syrdarya runoff would occur. An air temperature rise of 1-2 o C will intensify the process of ice degradation. In 1957-180 glaciers in the Aral Sea river basins lost 115.5 km 3 Of ice (approximately 104 km 3 of water), which constituted almost 20 per cent of the 1957 ice reserve. By 2000 another 14 per cent of the 1957 reserve were lost. By 2020 glaciers will lose at least another 10 per cent of their initial volume. Calculations of regional climatic scenarios by the year 2030 also indicate persistence of present runoff volumes accompanied by an increase in fluctuations from year. Longer-term assessments are more pessimistic, since, along with increasing evaporation, water resource inputs (snow and glaciers in the mountains) are continuously shrinking. (Author)

  10. Catalogue of polar bear (Ursus maritimus) maternal den locations in the Beaufort Sea and neighboring regions, Alaska, 1910-2010

    Science.gov (United States)

    Durner, George M.; Fischbach, Anthony S.; Amstrup, Steven C.; Douglas, David C.

    2010-01-01

    This report presents data on the approximate locations and methods of discovery of 392 polar bear (Ursus maritimus) maternal dens found in the Beaufort Sea and neighboring regions between 1910 and 2010 that are archived by the U.S. Geological Survey, Alaska Science Center, Anchorage, Alaska. A description of data collection methods, biases associated with collection method, primary time periods, and spatial resolution are provided. Polar bears in the Beaufort Sea and nearby regions den on both the sea ice and on land. Standardized VHF surveys and satellite radio telemetry data provide a general understanding of where polar bears have denned in this region over the past 3 decades. Den observations made during other research activities and anecdotal reports from other government agencies, coastal residents, and industry personnel also are reported. Data on past polar bear maternal den locations are provided to inform the public and to provide information for natural resource agencies in planning activities to avoid or minimize interference with polar bear maternity dens.

  11. Environment Protection (Alligator Rivers Region) Act 1978, No.28

    International Nuclear Information System (INIS)

    1978-01-01

    The main object of this Act is to provide for the appointment of a Supervising Scientist responsible for supervising protection of the environment in the Alligator Rivers Region of the Northern Territory from the effects of uranium mining operations. His functions include advising the competent Minister on the effects of uranium mining operations on the environment and on standards, practices and procedures for its protection and restoration. The Act also sets up a Co-ordinating Committee responsible for programmes for research into the environmental effects of such mining operations and also keeping under review standards, practices and procedures for environmental protection in relation thereto. Finally the Act provides for the establishment of a Research Institute managed by the Supervising Scientist, to promote and assist in research as well as to collect information on the environmental effects of uranium mining operations. (NEA) [fr

  12. Analysis of pumping-induced unsaturated regions beneath aperennial river

    Energy Technology Data Exchange (ETDEWEB)

    Su, G.W.; Jasperse, J.; Seymour, D.; Constantz, J.; Zhou, Q.

    2007-05-15

    The presence of an unsaturated region beneath a streambedduring groundwater pumping near streams reduces the pumping capacity whenit reaches the well screens, changes flow paths, and alters the types ofbiological transformations in the streambed sediments. Athree-dimensional, multi-phase flow model of two horizontal collectorwells along the Russian River near Forestville, California was developedto investigate the impact of varying the ratio of the aquifer tostreambed permeability on (1) the formation of an unsaturated regionbeneath the stream, (2) the pumping capacity, (3) stream-water fluxesthrough the streambed, and (4) stream-water travel times to the collectorwells. The aquifer to streambed permeability ratio at which theunsaturated region was initially observed ranged from 10 to 100. The sizeof the unsaturated region beneath the streambed increased as the aquiferto streambed permeability ratio increased. The simulations also indicatedthat for a particular aquifer permeability, decreasing the streambedpermeability by only a factor of 2-3 from the permeability wheredesaturation initially occurred resulted in reducing the pumpingcapacity. In some cases, the stream-water fluxes increased as thestreambed permeability decreased. However, the stream water residencetimes increased and the fraction of stream water that reached that thewells decreased as the streambed permeability decreased, indicating thata higher streambed flux does not necessarily correlate to greaterrecharge of stream water around the wells.

  13. Physicochemical composition of water of Sirdariya River (within of Sogd region)

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.; Khakimov, N.; Murtazaev, Kh.; Sufiev, A.

    2010-01-01

    Present article is devoted to physicochemical composition of water of Sirdariya River (within of Sogd region). During 12 months the physicochemical composition of above mentioned river was studied by means of water sampling from 10 points of river. The analysis was conducted and it was defined that the main contaminants of the river are the plant facilities, the deposits of radioactive ores and agricultural grounds.

  14. Uranium concentrations in stream waters and sediments from selected sites in the eastern Seward Peninsula, Koyukuk, and Charley River areas, and across South-Central Alaska

    International Nuclear Information System (INIS)

    Sharp, R.R. Jr.; Hill, D.E.

    1978-04-01

    During the summer of 1975, a 6-week reconnaissance was conducted in widespread areas of Alaska as part of the National Uranium Resource Evaluation (NURE) program; Water, stream sediment, and bedrock samples were taken from the eastern Seward Peninsula, from north of Koyukuk River, from the Charley River area, and from across south central Alaska. This report contains the LASL uranium determinations resulting from fluorometric analysis of the water samples and delayed-neutron counting of the stream sediment samples. Results of total uranium for 611 water and 641 sediment samples, from 691 stream locations, are presented. Overlays showing the numbered sample locations and graphically portraying the concentrations of uranium in water and stream sediment samples, at 1:250,000 scale for use with existing National Topographic Map Series (NTMS) sheets and published geologic maps, are provided as plates. The main purposes of this work are to make the uranium data available to the public in the standard computer format used in the NURE Hydrogeochemical and Stream Sediment Reconnaissance (i.e., with a DOE sample number giving the latitude and longitude of each sample location) and to provide uranium concentration overlays at the standard scale of 1:250,000 adopted by the DOE for the NURE program. It also allows a plausible explanation of differences between the uranium values for sediment as determined by acid dissolution/extraction/fluorometry and by delayed-neutron counting that were noted in the earlier report

  15. Volcanoes of the Wrangell Mountains and Cook Inlet region, Alaska: selected photographs

    Science.gov (United States)

    Neal, Christina A.; McGimsey, Robert G.; Diggles, Michael F.

    2001-01-01

    Alaska is home to more than 40 active volcanoes, many of which have erupted violently and repeatedly in the last 200 years. This CD-ROM contains 97 digitized color 35-mm images which represent a small fraction of thousands of photographs taken by Alaska Volcano Observatory scientists, other researchers, and private citizens. The photographs were selected to portray Alaska's volcanoes, to document recent eruptive activity, and to illustrate the range of volcanic phenomena observed in Alaska. These images are for use by the interested public, multimedia producers, desktop publishers, and the high-end printing industry. The digital images are stored in the 'images' folder and can be read across Macintosh, Windows, DOS, OS/2, SGI, and UNIX platforms with applications that can read JPG (JPEG - Joint Photographic Experts Group format) or PCD (Kodak's PhotoCD (YCC) format) files. Throughout this publication, the image numbers match among the file names, figure captions, thumbnail labels, and other references. Also included on this CD-ROM are Windows and Macintosh viewers and engines for keyword searches (Adobe Acrobat Reader with Search). At the time of this publication, Kodak's policy on the distribution of color-management files is still unresolved, and so none is included on this CD-ROM. However, using the Universal Ektachrome or Universal Kodachrome transforms found in your software will provide excellent color. In addition to PhotoCD (PCD) files, this CD-ROM contains large (14.2'x19.5') and small (4'x6') screen-resolution (72 dots per inch; dpi) images in JPEG format. These undergo downsizing and compression relative to the PhotoCD images.

  16. Establishing a baseline for regional scale monitoring of eelgrass (Zostera marina) habitat on the lower Alaska Peninsula

    Science.gov (United States)

    Hogrefe, Kyle R.; Ward, David H.; Donnelly, Tyrone F.; Dau, Niels

    2014-01-01

    Seagrass meadows, one of the world’s most widespread and productive ecosystems, provide a wide range of services with real economic value. Worldwide declines in the distribution and abundance of seagrasses and increased threats to coastal ecosystems from climate change have prompted a need to acquire baseline data for monitoring and protecting these important habitats. We assessed the distribution and abundance of eelgrass (Zostera marina) along nearly 1200 km of shoreline on the lower Alaska Peninsula, a region of expansive eelgrass meadows whose status and trends are poorly understood. We demonstrate the effectiveness of a multi-scale approach by using Landsat satellite imagery to map the total areal extent of eelgrass while integrating field survey data to improve map accuracy and describe the physical and biological condition of the meadows. Innovative use of proven methods and processing tools was used to address challenges inherent to remote sensing in high latitude, coastal environments. Eelgrass was estimated to cover ~31,000 ha, 91% of submerged aquatic vegetation on the lower Alaska Peninsula, nearly doubling the known spatial extent of eelgrass in the region. Mapping accuracy was 80%–90% for eelgrass distribution at locations containing adequate field survey data for error analysis.

  17. White phosphorus at Eagle River Flats, Alaska: A case history of waterfowl mortality

    Science.gov (United States)

    Sparling, Donald W.; Hoffman, David J.; Rattner, Barnett A.; Burton, G. Allen; Cairns, John

    2003-01-01

    White phosphorus has a limited distribution in the environment because it only occurs where it has been directly used by humans. It is not transported aerially for any distance and, due to its density, has a limited ability to disperse through water. Therefore, it is not a contaminant of broad-scale concern. However, where it does occur, it can cause substantial mortality or critically injure populations of waterfowl. This chronic harm includes impaired liver and kidney functioning, decreased respiratory efficiency, increased susceptibility to predation, loss of body mass, general weakening and malaise, and curtailment of reproductive functioning. Lethal effects occur around 3---4 mg/kg or approximately 3-6 ingested particles; sublethal effects can occur with ingestion of as little as a single particle. The impact of P4 on waterfowl populations nesting around ERF has never been estimated. Even if direct mortality on ERF could be estimated accurately in ducks, the delayed toxicity of P4 in swans (and presumably other species that use small grit size) and the potential for swans to fly away after ingesting a lethal dose of P4 could greatly underestimate the overall mortality. Inhibition of laying, reduced fertility and hatchability, and teratogenesis in hens ingesting even a small amount of P4 could potentially have, an effect on populations greater than that exhibited by direct mortality. Predators such as bald eagles and gulls are also at risk due to the toxicity of pelletized, dissolved, and assimilated P4 in prey organisms. Although the U.S. Army stopped using P4 in wetlands in 1993 and remediation efforts have been underway since 1995, waterfowl mortality is expected to continue for several more years. Because Eagle River Flats is only one of several sites where P4 has been found in wetland conditions, further biological investigation is warranted at these other sites.

  18. Analytical data and sample locality map for aqua-regia leachates of stream sediments analyzed by ICP, and emission spectrographic and ICP results for many NURE stream sediments from the Killik River Quadrangle, Alaska

    International Nuclear Information System (INIS)

    Motooka, J.M.; Adrian, B.M.; Church, S.E.; McDougal, C.M.; Fife, J.B.

    1989-01-01

    A U.S. Geological Survey report is presented giving analytical data and sample locality map for aqua-regia leachates of stream sediments analyzed by ICP, and emission spectrographic and ICP results for many NURE stream sediments from the Killik River Quadrangle, Alaska

  19. Utilizing chromophoric dissolved organic matter measurements to derive export and reactivity of dissolved organic carbon exported to the Arctic Ocean: A case study of the Yukon River, Alaska

    Science.gov (United States)

    Spencer, R.G.M.; Aiken, G.R.; Butler, K.D.; Dornblaser, M.M.; Striegl, Robert G.; Hernes, P.J.

    2009-01-01

    The quality and quantity of dissolved organic matter (DOM) exported by Arctic rivers is known to vary with hydrology and this exported material plays a fundamental role in the biogeochemical cycling of carbon at high latitudes. We highlight the potential of optical measurements to examine DOM quality across the hydrograph in Arctic rivers. Furthermore, we establish chromophoric DOM (CDOM) relationships to dissolved organic carbon (DOC) and lignin phenols in the Yukon River and model DOC and lignin loads from CDOM measurements, the former in excellent agreement with long-term DOC monitoring data. Intensive sampling across the historically under-sampled spring flush period highlights the importance of this time for total export of DOC and particularly lignin. Calculated riverine DOC loads to the Arctic Ocean show an increase from previous estimates, especially when new higher discharge data are incorporated. Increased DOC loads indicate decreased residence times for terrigenous DOM in the Arctic Ocean with important implications for the reactivity and export of this material to the Atlantic Ocean. Citation: Spencer, R. G. M., G. R. Aiken, K. D. Butler, M. M. Dornblaser, R. G. Striegl, and P. J. Hernes (2009), Utilizing chromophoric dissolved organic matter measurements to derive export and reactivity of dissolved organic carbon exported to the Arctic Ocean: A case study of the Yukon River, Alaska, Geophys. Res. Lett., 36, L06401, doi:10.1029/ 2008GL036831. Copyright 2009 by the American Geophysical Union.

  20. Contamination profiles of perfluoroalkyl substances in five typical rivers of the Pearl River Delta region, South China.

    Science.gov (United States)

    Pan, Chang-Gui; Ying, Guang-Guo; Liu, You-Sheng; Zhang, Qian-Qian; Chen, Zhi-Feng; Peng, Feng-Jiao; Huang, Guo-Yong

    2014-11-01

    A survey on contamination profiles of eighteen perfluoroalkyl substances (PFASs) was performed via high performance liquid chromatography-tandem mass spectrometry for surface water and sediments from five typical rivers of the Pearl River Delta region, South China in summer and winter in 2012. The total concentrations of the PFASs in the water phase of the five rivers ranged from 0.14 to 346.72 ng L(-1). The PFAS concentrations in the water phase were correlated positively to some selected water quality parameters such as chemical oxygen demand (COD) (0.7913) and conductivity (0.5642). The monitoring results for the water samples showed significant seasonal variations, while those for the sediment samples showed no obvious seasonal variations. Among the selected 18 PFASs, perfluorooctane sulfonic acid (PFOS) was the dominant PFAS compound both in water and sediment for two seasons with its maximum concentration of 320.5 ng L(-1) in water and 11.4 ng g(-1) dry weight (dw) in sediment, followed by perfluorooctanoic acid (PFOA) with its maximum concentration of 26.48 ng L(-1) in water and 0.99 ng g(-1) dw in sediment. PFOS and PFOA were found at relatively higher concentrations in the Shima River and Danshui River than in the other three rivers (Xizhijiang River, Dongjiang River and Shahe River). The principal component analysis for the PFASs concentrations in water and sediment separated the sampling sites into two groups: rural and agricultural area, and urban and industrial area, suggesting the PFASs in the riverine environment were mainly originated from industrial and urban activities in the region. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Effect of root strength and soil saturation on hillslope stability in forests with natural cedar decline in headwater regions of SE Alaska.

    Science.gov (United States)

    Adelaide C. Johnson; Peter. Wilcock

    1998-01-01

    A natural decline in the population of yellow-cedar (Chamaecyparis nootkatensis) is occurring in pristine southeast Alaska forests and may be the most significant forest decline in the western United States. The frequency of landslides in cedar decline areas is three times larger than in areas of healthy forest. Three regions are investigated in...

  2. Evaluation of a wetland classification system devised for management in a region with a high cover of peatlands: an example from the Cook Inlet Basin, Alaska

    Science.gov (United States)

    The manuscript is part of an FY14 RAP product: "Functional Assessment of Alaska Peatlands in Cook Inlet Basin: A report to Region 10". This report included this technical information product which is a manuscript that has now been fully revised, reviewed and published...

  3. Fish distributions in the Rondegat River, Cape Floristic Region ...

    African Journals Online (AJOL)

    Alien fishes are considered the most serious threat to native headwater stream fishes in South Africa. A 4 km reach of the Rondegat River is the first section of a South African river to be rehabilitated through the attempted removal of alien fish by using the piscicide rotenone. The objectives of the current study were to ...

  4. Tephrochronology of the Brooks River Archaeological District, Katmai National Park and Preserve, Alaska: What can and cannot be done with tephra deposits

    Science.gov (United States)

    Riehle, J.R.; Dumond, D.E.; Meyer, C.E.; Schaaf, J.M.

    2000-01-01

    The Brooks River Archaeological District (BRAD) in Katmai National Park and Preserve is a classical site for the study of early humans in Alaska. Because of proximity to the active Aleutian volcanic arc, there are numerous tephra deposits in the BRAD, which are potentially useful for correlating among sites of archaeological investigations. Microprobe analyses of glass separates show, however, that most of these tephra deposits are heterogeneous mixtures of multiple glass populations. Some glasses are highly similar to pyroclasts of Aniakchak Crater (160 km to the south), others are similar to pyroclasts in the nearby Valley of Ten Thousand Smokes, and some are similar to no other tephra samples from the Alaska Peninsula. Moreover, tephra deposits in any one archaeological study site are not always similar to those from nearby sites, indicating inconsistent preservation of these mainly thin, fine-grained deposits. At least 15, late Holocene tephra deposits are inferred at the BRAD. Their heterogeneity is the result of either eruptions of mixed or heterogeneous magmas, like the 1912 Katmai eruption, or secondary mixing of closely succeeding tephra deposits. Because most cannot be reliably distinguished from one another on the basis of megascopic properties, their utility for correlations is limited. At least one deposit can be reliably identified because of its thickness (10 cm) and colour stratification. Early humans seem not to have been significantly affected by these tephra falls, which is not surprising in view of the resilience exhibited by both plants and animals following the 1912 Katmai eruption.

  5. Observations and first reports of saprolegniosis in Aanaakłiq, broad whitefish (Coregonus nasus), from the Colville River near Nuiqsut, Alaska

    Science.gov (United States)

    Sformo, Todd L.; Adams, Billy; Seigle, John C.; Ferguson, Jayde A.; Purcell, Maureen K.; Stimmelmayr, Raphaela; Welch, Joseph H.; Ellis, Leah M.; Leppi, Jason C.; George, John C.

    2017-12-01

    We report the first confirmed cases (2013-2016) of saprolegniosis caused by water mold from the genus Saprolegnia in Aanaakłiq, broad whitefish (Coregonus nasus), from the Colville River near Nuiqsut, Alaska. While this mold is known to be worldwide, these instances represent the first cases in Nuiqsut and only the second instance on a single fish on the North Slope, occurring in 1980. We describe the collaborative work on monitoring this emerging disease. Because fish constitute a critical component of the diet in Nuiqsut and fishing is an integral part of Inupiaq nutritional and cultural subsistence activities overall, individual subsistence fishers, local governmental entities, and Alaska Native organizations representing Nuiqsut requested an examination of affected fish and information on possible drivers of this emerging disease. The collaborative work described here ranges from recording fishermen observations, acquiring fish and mold specimens, histopathology, and molecular identification of the mold. This work, not currently grant-funded, begins with Native observation that incorporates western scientific methods and involves local, state, and federal departments as well as for-profit and non-profit organizations. Additionally, we report the more recent (2016) observation of this disease in a second species of whitefish, Pikuktuuq, humpback whitefish (Coregonus pidschain).

  6. The Pleistocene rivers of the English Channel region

    Science.gov (United States)

    Antoine, Pierre; Coutard, Jean-Pierre; Gibbard, Philip; Hallegouet, Bernard; Lautridou, Jean-Pierre; Ozouf, Jean-Claude

    2003-02-01

    The Pleistocene history of river systems that enter the English Channel from northern France and southern England is reviewed. During periods of low sea-level (cold stages) these streams were tributaries of the Channel River. In southern England the largest, the River Solent, is an axial stream that has drained the Hampshire Basin from the Early Pleistocene or late Pliocene. Other streams of southern England may be of similar antiquity but their records are generally short and their sedimentary history have been destroyed, as in northern Brittany, by coastal erosion and valley deepening as a consequence of tectonic uplift. In northern France, the Seine and Somme rivers have very well developed terrace systems recording incision that began at around 1 Ma. The uplift rate, deduced from the study of these terrace systems, is of 55 to 60 m myr-1 since the end of the Early Pleistocene. Generally the facies and sedimentary structures indicate that the bulk of the deposits in these rivers accumulated in braided river environments under periglacial climates in all the area around the Channel. Evolution of the rivers reflects their responses to climatic change, local geological structure and long-term tectonic activity. In this context the Middle Somme valley is characterised by a regular pattern in which incision occurs at the beginning of each glacial period within a general background of uplift. Nevertheless the response of the different rivers to climatic variations, uplift and sea-level changes is complex and variable according to the different parts of the river courses.

  7. Phytomass in southwest Alaska.

    Science.gov (United States)

    Bert R. Mead

    2000-01-01

    Phytomass tables are presented for southwest Alaska. The methods used to estimate plant weight and occurrence in the river basin are described and discussed. Average weight is shown for each sampled species of tree, shrub, grass, forb, lichen, and moss in 19 forest and 48 nonforest vegetation types. Species frequency of occurrence and species constancy within the type...

  8. Stream network geomorphology mediates predicted vulnerability of anadromous fish habitat to hydrologic change in southeast Alaska

    Science.gov (United States)

    Matthew R. Sloat; Gordon H. Reeves; Kelly R. Christiansen

    2016-01-01

    In rivers supporting Pacific salmon in southeast Alaska, USA, regional trends toward a warmer, wetter climate are predicted to increase mid- and late-21st-century mean annual flood size by 17% and 28%, respectively. Increased flood size could alter stream habitats used by Pacific salmon for reproduction, with negative consequences for the substantial economic, cultural...

  9. River water quality in the northern sugarcane-producing regions of ...

    African Journals Online (AJOL)

    2011-02-16

    Feb 16, 2011 ... Sugarcane production in South Africa occurs exclusively in the eastern regions of ... transboundary rivers, making their management internation- ...... KOEGELENBERG FH (2004) Irrigation User's Manual – Chapter 5: Water.

  10. Process analysis of regional aerosol pollution during spring in the Pearl River Delta region, China

    Science.gov (United States)

    Fan, Qi; Lan, Jing; Liu, Yiming; Wang, Xuemei; Chan, Pakwai; Hong, Yingying; Feng, Yerong; Liu, Yexin; Zeng, Yanjun; Liang, Guixiong

    2015-12-01

    A numerical simulation analysis was performed for three air pollution episodes in the Pearl River Delta (PRD) region during March 2012 using the third-generation air quality modeling system Models-3/CMAQ. The results demonstrated that particulate matter was the primary pollutant for all three pollution episodes and was accompanied by relatively low visibility in the first two episodes. Weather maps indicate that the first two episodes occurred under the influence of warm, wet southerly air flow systems that led to high humidity throughout the region. The liquid phase reaction of gaseous pollutants resulted in the generation of fine secondary particles, which were identified as the primary source of pollution in the first two episodes. The third pollution episode occurred during a warming period following a cold front. Relative humidity was lower during this episode, and coarse particles were the major pollution contributor. Results of process analysis indicated that emissions sources, horizontal transport and vertical transport were the primary factors affecting pollutant concentrations within the near-surface layer during all three episodes, while aerosol processes, cloud processes, horizontal transport and vertical transport had greater influence at approximately 900 m above ground. Cloud processes had a greater impact during the first two pollution episodes because of the higher relative humidity. In addition, by comparing pollution processes from different cities (Guangzhou and Zhongshan), the study revealed that the first two pollution episodes were the result of local emissions within the PRD region and transport between surrounding cities, while the third episode exhibited prominent regional pollution characteristics and was the result of regional pollutant transport.

  11. Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Inmachuk, Kugruk, Kiwalik, and Koyuk River drainages, Granite Mountain, and the northern Darby Mountains, Bendeleben, Candle, Kotzebue, and Solomon quadrangles, Alaska

    Science.gov (United States)

    Werdon, Melanie B.; Granitto, Matthew; Azain, Jaime S.

    2015-01-01

    The State of Alaska’s Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska’s statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. As part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly identify areas in Alaska with SCM potential. The USGS is also undertaking SCM-related geologic studies in Alaska through the federally funded Alaska Critical Minerals cooperative project. DGGS and USGS share the goal of evaluating Alaska’s strategic and critical minerals potential and together created a Letter of Agreement (signed December 2012) and a supplementary Technical Assistance Agreement (#14CMTAA143458) to facilitate the two agencies’ cooperative work. Under these agreements, DGGS contracted the USGS in Denver to reanalyze historical USGS sediment samples from Alaska. For this report, DGGS funded reanalysis of 653 historical USGS sediment samples from the statewide Alaska Geochemical Database Version 2.0 (AGDB2; Granitto and others, 2013). Samples were chosen from an area covering portions of the Inmachuk, Kugruk, Kiwalik, and Koyuk river drainages, Granite Mountain, and the northern Darby Mountains, located in the Bendeleben, Candle, Kotzebue, and Solomon quadrangles of eastern Seward Peninsula, Alaska (fig. 1). The USGS was responsible for sample retrieval from the National Geochemical Sample Archive (NGSA) in Denver, Colorado through the final quality assurance/quality control (QA/QC) of the geochemical analyses obtained through the USGS contract

  12. Ecological studies on the freshwater fishes of the Alligator Rivers Region, Northern Territory

    International Nuclear Information System (INIS)

    Bishop, K.A.; Allen, S.A.; Pollard, D.A.; Cook, M.G.

    1986-01-01

    The tropical climate of the Alligator Rivers Region of the Northern Territory has a distinctive Wet-Dry cycle resulting in seasonal flows in the creeks and rivers of its catchments. The present study, begun during August 1978, aimed at developing an ecological monitoring system that would detect changes in freshwater fish communities brought about by recent uranium mining and processing in the lowlands of the region

  13. Heavy metal contamination status and source apportionment in sediments of Songhua River Harbin region, Northeast China.

    Science.gov (United States)

    Li, Ning; Tian, Yu; Zhang, Jun; Zuo, Wei; Zhan, Wei; Zhang, Jian

    2017-02-01

    The Songhua River represents one of the seven major river systems in China. It flows through Harbin city with 66 km long, locating in the northern China with a longer winter time. This paper aimed to study concentration distributions, stability, risk assessment, and source apportionment of heavy metals including chromium (Cr), cadmium (Cd), lead (Pb), mercury (Hg), arsenic (As), copper (Cu), zinc (Zn), and nickel (Ni) in 11 selected sections of the Songhua River Harbin region. Results showed that Cr, Cd, Pb, Hg, and As exceeded their respective geochemical background values in sediments of most monitoring sections. Compared with other important rivers and lakes in China, Cr, Hg, Cd, and As pollutions in surface sediments were above medium level. Further analysis of chemical speciation indicated that Cr and As in surface sediments were relatively stable while Pb and Cd were easily bioavailable. Correlation analysis revealed sources of these metals except As might be identical. Pollution levels and ecological risks of heavy metals in surface sediments presented higher in the mainstream region (45° 47.0' N ~ 45° 53.3' N, 126° 37.0' E ~ 126° 42.1' E). Source apportionment found Hejiagou and Ashi River were the main contributors to metal pollution of this region. Thus, anthropogenic activities along the Hejiagou and Ashi River should be restricted in order to protect the Songhua River Harbin region from metal contamination.

  14. Life cycle costs for Alaska bridges.

    Science.gov (United States)

    2014-08-01

    A study was implemented to assist the Alaska Department of Transportation and Public Facilities (ADOT&PF) with life cycle costs for : the Alaska Highway Bridge Inventory. The study consisted of two parts. Part 1 involved working with regional offices...

  15. Increased wetness confounds Landsat-derived NDVI trends in the central Alaska North Slope region, 1985-2011

    Science.gov (United States)

    Raynolds, Martha K.; Walker, Donald A.

    2016-08-01

    Satellite data from the circumpolar Arctic have shown increases in vegetation indices correlated to warming air temperatures (e.g. Bhatt et al 2013 Remote Sensing 5 4229-54). However, more information is needed at finer scales to relate the satellite trends to vegetation changes on the ground. We examined changes using Landsat TM and ETM+ data between 1985 and 2011 in the central Alaska North Slope region, where the vegetation and landscapes are relatively well-known and mapped. We calculated trends in the normalized difference vegetation index (NDVI) and tasseled-cap transformation indices, and related them to high-resolution aerial photographs, ground studies, and vegetation maps. Significant, mostly negative, changes in NDVI occurred in 7.3% of the area, with greater change in aquatic and barren types. Large reflectance changes due to erosion, deposition and lake drainage were evident. Oil industry-related changes such as construction of artificial islands, roads, and gravel pads were also easily identified. Regional trends showed decreases in NDVI for most vegetation types, but increases in tasseled-cap greenness (56% of study area, greatest for vegetation types with high shrub cover) and tasseled-cap wetness (11% of area), consistent with documented degradation of polygon ice wedges, indicating that increasing cover of water may be masking increases in vegetation when summarized using the water-sensitive NDVI.

  16. Ecological restoration and effect investigation of a river wetland in a semi-arid region, China

    Science.gov (United States)

    Xu, S.; Jiang, X.; Liu, Y.; Fu, Y.; Zhao, Q.

    2015-05-01

    River wetlands are heavily impacted by human intervention. The degradation and loss of river wetlands has made the restoration of river ecosystems a top priority. How to rehabilitate rivers and their services has been a research focus. The main goal of it is to restore the river wetland ecosystems with ecological methods. The Gudong River was selected as a study site in Chaoyang city in this study. Based on the analysis of interference factors in the river wetland degradation, a set of restoration techniques were proposed and designed for regional water level control, including submerged dikes, ecological embankments, revegetation and dredging. The restoration engineering has produced good results in water quality, eco-environment, and landscape. Monthly reports of the Daling River show that the water quality of Gudong River was better than Grade III in April 2013 compared with Grade V in May 2012. The economic benefit after restoration construction is 1.71 million RMB per year, about 1.89 times that before. The ratio of economic value, social value and eco-environmental value is 1:4:23.

  17. River reach classification for the Greater Mekong Region at high spatial resolution

    Science.gov (United States)

    Ouellet Dallaire, C.; Lehner, B.

    2014-12-01

    River classifications have been used in river health and ecological assessments as coarse proxies to represent aquatic biodiversity when comprehensive biological and/or species data is unavailable. Currently there are no river classifications or biological data available in a consistent format for the extent of the Greater Mekong Region (GMR; including the Irrawaddy, the Salween, the Chao Praya, the Mekong and the Red River basins). The current project proposes a new river habitat classification for the region, facilitated by the HydroSHEDS (HYDROlogical SHuttle Elevation Derivatives at multiple Scales) database at 500m pixel resolution. The classification project is based on the Global River Classification framework relying on the creation of multiple sub-classifications based on different disciplines. The resulting classes from the sub-classification are later combined into final classes to create a holistic river reach classification. For the GMR, a final habitat classification was created based on three sub-classifications: a hydrological sub-classification based only on discharge indices (river size and flow variability); a physio-climatic sub-classification based on large scale indices of climate and elevation (biomes, ecoregions and elevation); and a geomorphological sub-classification based on local morphology (presence of floodplains, reach gradient and sand transport). Key variables and thresholds were identified in collaboration with local experts to ensure that regional knowledge was included. The final classification is composed 54 unique final classes based on 3 sub-classifications with less than 15 classes each. The resulting classifications are driven by abiotic variables and do not include biological data, but they represent a state-of-the art product based on best available data (mostly global data). The most common river habitat type is the "dry broadleaf, low gradient, very small river". These classifications could be applied in a wide range of

  18. Contamination with retinoic acid receptor agonists in two rivers in the Kinki region of Japan.

    Science.gov (United States)

    Inoue, Daisuke; Nakama, Koki; Sawada, Kazuko; Watanabe, Taro; Takagi, Mai; Sei, Kazunari; Yang, Min; Hirotsuji, Junji; Hu, Jianying; Nishikawa, Jun-ichi; Nakanishi, Tsuyoshi; Ike, Michihiko

    2010-04-01

    This study was conducted to investigate the agonistic activity against human retinoic acid receptor (RAR) alpha in the Lake Biwa-Yodo River and the Ina River in the Kinki region of Japan. To accomplish this, a yeast two-hybrid assay was used to elucidate the spatial and temporal variations and potential sources of RARalpha agonist contamination in the river basins. RARalpha agonistic activity was commonly detected in the surface water samples collected along two rivers at different periods, with maximum all-trans retinoic acid (atRA) equivalents of 47.6 ng-atRA/L and 23.5 ng-atRA/L being observed in Lake Biwa-Yodo River and Ina River, respectively. The results indicated that RARalpha agonists are always present and widespread in the rivers. Comparative investigation of RARalpha and estrogen receptor alpha agonistic activities at 20 stations along each river revealed that the spatial variation pattern of RARalpha agonist contamination was entirely different from that of the estrogenic compound contamination. This suggests that the effluent from municipal wastewater treatment plants, a primary source of estrogenic compounds, seemed not to be the cause of RARalpha agonist contamination in the rivers. Fractionation using high performance liquid chromatography (HPLC) directed by the bioassay found two bioactive fractions from river water samples, suggesting the presence of at least two RARalpha agonists in the rivers. Although a trial conducted to identify RARalpha agonists in the major bioactive fraction was not completed as part of this study, comparison of retention times in HPLC analysis and quantification with liquid chromatography-mass spectrometry analysis revealed that the major causative contaminants responsible for the RARalpha agonistic activity were not RAs (natural RAR ligands) and 4-oxo-RAs, while 4-oxo-RAs were identified as the major RAR agonists in sewage in Beijing, China. These findings suggest that there are unknown RARalpha agonists with high

  19. An earth remote sensing satellite- 1 Synthetic Aperture Radar Mosaic of the Tanana River Basin in Alaska

    Science.gov (United States)

    Wivell, Charles E.; Olmsted, Coert; Steinwand, Daniel R.; Taylor, Christopher

    1993-01-01

    Because the pixel location in a line of Synthetic Aperture Radar (SAR) image data is directly related to the distance the pixel is from the radar, terrain elevations cause large displacement errors in the geo-referenced location of the pixel. This is especially true for radar systems with small angles between the nadir and look vectors. Thus, to geo-register a SAR image accurately, the terrain of the area must be taken into account. (Curlander et al., 1987; Kwok et al., 1987, Schreier et al., 1990; Wivell et al., 1992). As part of the 1992 National Aeronautics and Space Administration's Earth Observing System Version 0 activities, a prototype SAR geocod-. ing and terrain correction system was developed at the US. Geological Survey's (USGS) E~os Data Center (EDC) in Sioux Falls, South Dakota. Using this system with 3-arc-second digital elevation models (DEMs) mosaicked at the ED^ Alaska Field Office, 21 ERS-I s.4~ scenes acquired at the Alaska SAR Facility were automatically geocoded, terrain corrected, and mosaicked. The geo-registered scenes were mosaicked using a simple concatenation.

  20. Regional Sediment Budget of the Columbia River Littoral Cell, USA

    Science.gov (United States)

    Buijsman, Maarten C.; Sherwood, C.R.; Gibbs, A.E.; Gelfenbaum, G.; Kaminsky, G.M.; Ruggiero, P.; Franklin, J.

    2002-01-01

    Summary -- In this Open-File Report we present calculations of changes in bathymetric and topographic volumes for the Grays Harbor, Willapa Bay, and Columbia River entrances and the adjacent coasts of North Beach, Grayland Plains, Long Beach, and Clatsop Plains for four intervals: pre-jetty - 1920s (Interval 1), 1920s - 1950s (Interval 2), 1950s - 1990s (Interval 3), and 1920s 1990s (Interval 4). This analysis is part of the Southwest Washington Coastal Erosion Study (SWCES), the goals of which are to understand and predict the morphologic behavior of the Columbia River littoral cell on a management scale of tens of kilometers and decades. We obtain topographic Light Detection and Ranging (LIDAR) data from a joint project by the U.S. Geological Survey (USGS), National Oceanic and Atmospheric Administration (NOAA), National Aeronautic and Space Administration (NASA), and the Washington State Department of Ecology (DOE) and bathymetric data from the U.S. Coast and Geodetic Survey (USC&GS), U.S. Army Corps of Engineers (USACE), USGS, and the DOE. Shoreline data are digitized from T-Sheets and aerial photographs from the USC&GS and National Ocean Service (NOS). Instead of uncritically adjusting each survey to NAVD88, a common vertical land-based datum, we adjust some surveys to produce optimal results according to the following criteria. First, we minimize offsets in overlapping surveys within the same era, and second, we minimize bathymetric changes (relative to the 1990s) in deep water, where we assume minimal change has taken place. We grid bathymetric and topographic datasets using kriging and triangulation algorithms, calculate bathymetric-change surfaces for each interval, and calculate volume changes within polygons that are overlaid on the bathymetric-change surfaces. We find similar morphologic changes near the entrances to Grays Harbor and the Columbia River following jetty construction between 1898 and 1916 at the Grays Harbor entrance and between 1885 and

  1. Engaging Local Communities in Arctic Observing Networks: A Collaborative Shoreline Change Risk WebGIS for Alaska's Arctic Slope Region

    Science.gov (United States)

    Brady, M.

    2017-12-01

    This study engaged local community stakeholders in Alaska's Arctic Slope Region to develop a web-based shoreline change risk geographic information system (WebGIS) in collaboration with the North Slope Borough and its residents. The value of the effort includes rich spatial documentation of local risks across the vast, remote, and rapidly changing shoreline, and identification of local manager information needs to direct WebGIS development. The study advances our understanding of shoreline change problems from the perspective of local Arctic communities beyond municipal impacts while building decision support. Over fifty local residents in three communities with collective coastal knowledge that extends across the National Petroleum Reserve - Alaska and Arctic National Wildlife Refuge shared their perspectives on hard copy maps. Sixteen managers provided usability perceptions of a beta WebGIS with shoreline change susceptibility information summarized at relevant asset locations such as subsistence camps. The hard copy maps with 300 "problem places" were digitized for analysis, which revealed problems across the coastline, especially challenges to boating for subsistence hunting such as shoaling cutting off access and creating hazards. The usability workshop revealed specific information needs including the need to monitor impacts at decommissioned national defense radar sites repurposed by locals to centralize oil and gas activity. These results were analyzed using an Instructional Systems Design (ISD) framework consisting of front-end and formative WebGIS evaluation phases. The front-end evaluation is the local input on hard copy maps, which provided local verification of coastal risks. The formative evaluation is the usability workshop with managers, which informed WebGIS development while promoting user buy-in. In terms of product and process, the local knowledge and information needs collected are significant because they establish local engagement with the

  2. Groundwater Discharges to Rivers in the Western Canadian Oil Sands Region

    Science.gov (United States)

    Ellis, J.; Jasechko, S.

    2016-12-01

    Groundwater discharges into rivers impacts the movement and fate of nutrients and contaminants in the environment. Understanding groundwater-surface water interactions is especially important in the western Canadian oil sands, where groundwater contamination risks are elevated and baseline water chemistry data is lacking, leading to substantial uncertainties about anthropogenic influences on local river quality. High salinity groundwater springs sourced from deep aquifers, comprised of Pleistocene-aged glacial meltwater, are known to discharge into many rivers in the oil sands. Understanding connections between deep aquifers and surficial waterways is important in order to determine natural inputs into these rivers and to assess the potential for injected wastewater or oil extraction fluids to enter surface waters. While these springs have been identified, their spatial distribution along rivers has not been fully characterized. Here we present river chemistry data collected along a number of major river corridors in the Canadian oil sands region. We show that saline groundwater springs vary spatially along the course of these rivers and tend to be concentrated where the rivers incise Devonian- or Cretaceous-aged aquifers along an evaporite dissolution front. Our results suggest that water sourced from Devonian aquifers may travel through bitumen-bearing Cretaceous units and discharge into local rivers, implying a strong groundwater-surface water connection in specialized locations. These findings indicate that oil sands process-affected waters that are injected at depth have the potential to move through these aquifers and reach the rivers at the surface at some time in the future. Groundwater-surface water interactions remain key to understanding the risks oil sands activities pose to aquatic ecosystems and downstream communities.

  3. Environment Protection (Alligator Rivers Region) Amendment Act 1987 - No 17 of 1987

    International Nuclear Information System (INIS)

    1987-01-01

    This Act amends the Environment Protection (Alligator Rivers Region) Act 1978. The amendments mainly concern definition of general mining operations and specification of the functions of the Supervisory Scientist and the Research Institute in relation to general mining in an environment conservation zone (parts of the Alligator Rivers Region). The 1978 Act provided for the appointment of a Supervising Scientist responsible for supervising protection of the environment against the effects of uranium mining in the Region, and for the creation of a Research Institute under his management. (NEA) [fr

  4. Mitochondrial DNA phylogeography of least cisco Coregonus sardinella in Alaska.

    Science.gov (United States)

    Padula, V M; Causey, D; López, J A

    2017-03-01

    This study presents the first detailed analysis of the mitochondrial DNA diversity of least cisco Coregonus sardinella in Alaska using a 678 bp segment of the control region (D-loop) of the mitochondrial genome. Findings suggest that the history of C. sardinella in Alaska differs from that of other species of Coregonus present in the state and surrounding regions. The examined populations of C. sardinella are genetically diverse across Alaska. Sixty-eight distinct mitochondrial haplotypes were identified among 305 individuals sampled from nine locations. The haplotype minimum spanning network and phylogeny showed a modest level of geographic segregation among haplotypes, suggesting high levels of on-going or recent connectivity among distant populations. Observed Φ ST values and the results of homogeneity and AMOVAs indicate incipient genetic differentiation between aggregations in three broad regional groups. Sites north of the Brooks Range formed one group, sites in the Yukon and Selawik Rivers formed a second group and sites south of the Yukon drainage formed the third group. Overall, the sequence data showed that a large proportion of mtDNA genetic variation in C. sardinella is shared across Alaska, but this variation is not homogeneously distributed across all regions and for all haplotype groups. © 2017 The Fisheries Society of the British Isles.

  5. Regional scale groundwater modelling study for Ganga River basin

    Science.gov (United States)

    Maheswaran, R.; Khosa, R.; Gosain, A. K.; Lahari, S.; Sinha, S. K.; Chahar, B. R.; Dhanya, C. T.

    2016-10-01

    Subsurface movement of water within the alluvial formations of Ganga Basin System of North and East India, extending over an area of 1 million km2, was simulated using Visual MODFLOW based transient numerical model. The study incorporates historical groundwater developments as recorded by various concerned agencies and also accommodates the role of some of the major tributaries of River Ganga as geo-hydrological boundaries. Geo-stratigraphic structures, along with corresponding hydrological parameters,were obtained from Central Groundwater Board, India,and used in the study which was carried out over a time horizon of 4.5 years. The model parameters were fine tuned for calibration using Parameter Estimation (PEST) simulations. Analyses of the stream aquifer interaction using Zone Budget has allowed demarcation of the losing and gaining stretches along the main stem of River Ganga as well as some of its principal tributaries. From a management perspective,and entirely consistent with general understanding, it is seen that unabated long term groundwater extraction within the study basin has induced a sharp decrease in critical dry weather base flow contributions. In view of a surge in demand for dry season irrigation water for agriculture in the area, numerical models can be a useful tool to generate not only an understanding of the underlying groundwater system but also facilitate development of basin-wide detailed impact scenarios as inputs for management and policy action.

  6. Genetic characterization of Kenai brown bears (Ursus arctos): Microsatellite and mitochondrial DNA control region variation in brown bears of the Kenai Peninsula, south central Alaska

    Science.gov (United States)

    Jackson, J.V.; Talbot, S.L.; Farley, S.

    2008-01-01

    We collected data from 20 biparentally inherited microsatellite loci, and nucleotide sequence from the maternally inherited mitochondrial DNA (mtDNA) control region, to determine levels of genetic variation of the brown bears (Ursus arctos L., 1758) of the Kenai Peninsula, south central Alaska. Nuclear genetic variation was similar to that observed in other Alaskan peninsular populations. We detected no significant inbreeding and found no evidence of population substructuring on the Kenai Peninsula. We observed a genetic signature of a bottleneck under the infinite alleles model (IAM), but not under the stepwise mutation model (SMM) or the two-phase model (TPM) of microsatellite mutation. Kenai brown bears have lower levels of mtDNA haplotypic diversity relative to most other brown bear populations in Alaska. ?? 2008 NRC.

  7. Reconnaissance from Fort Hamlin to Kotzebue Sound, Alaska, by way of Dall, Kanuti, Allen, and Kowak rivers

    Science.gov (United States)

    Mendenhall, W.C.

    1902-01-01

    The reconnaissance described in the following pages was carried out in pursuance of a plan which has been followed for some years by the United States Geological Survey in the topographic and geologic exploration of the little-known parts of Alaska and in the collection of such information as will be of value not only to the scientific world, but to the prospector, the miner, and the trader. Capital disappears and years are wasted by prospectors who push out beyond the shifting frontier and pursue their search for gold where gold is not to be expected, and lives are being continually lost because the location and character of trails, drainage ways, and mountain ranges and passes are unknown, or because the knowledge which a few possess is not in a form available for the use of others.

  8. Geologic map of the west-central Buffalo National River region, northern Arkansas

    Science.gov (United States)

    Hudson, Mark R.; Turner, Kenzie J.

    2014-01-01

    This map summarizes the geology of the west-central Buffalo National River region in the Ozark Plateaus region of northern Arkansas. Geologically, the region lies on the southern flank of the Ozark dome, an uplift that exposes oldest rocks at its center in Missouri. Physiographically, the map area spans the Springfield Plateau, a topographic surface generally held up by Mississippian cherty limestone and the higher Boston Mountains to the south, held up by Pennsylvanian rocks. The Buffalo River flows eastward through the map area, enhancing bedrock erosion of an approximately 1,600-ft- (490-m-) thick sequence of Ordovician, Mississippian, and Pennsylvanian carbonate and clastic sedimentary rocks that have been mildly deformed by a series of faults and folds. Quaternary surficial units are present as alluvial deposits along major streams, including a series of terrace deposits from the Buffalo River, as well as colluvium and landslide deposits mantling bedrock on hillslopes.

  9. Savannah River Region: Transition between the Gulf and Atlantic Coastal Plains. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Zullo, V.A.; Harris, W.B.; Price, V. [eds.

    1990-12-31

    The focus of the this conference of Coastal Plains geologists was on the Savannah River region of Georgia and South Carolina, and particularly on the geology of the US Department of Energy`s 300 square mile Savannah River Site (SRS) in western South Carolina. Current geological studies indicate that the Mesozoic-Cenozoic section in the Savannah River region is transitional between that of the Gulf Coastal Plain to the southwest and that of the Atlantic Coastal Plain to the northeast. With the transitional aspect of the region as its theme, the first session was devoted to overviews of Cretaceous and Paleogene geology in the Gulf and Atlantic Coastal Plains. Succeeding presentations and resulting discussions dealt with more specific problems in structural, lithostratigraphic, hydrological, biostratigraphic, and cyclostratigraphic analysis, and of correlation to standard stratigraphic frameworks. For these conference proceedings, individual papers have been processed separately for the Energy Data Base.

  10. Lower Colorado River Geographic Response Plan Web Mapping Service, Region 9, 2012, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — This map service is comprised of data related to Geographic Response Plans (GRPs) for the Lower Colorado River. Data layers were obtained from nationwide GIS...

  11. Reconstructing satellite images to quantify spatially explicit land surface change caused by fires and succession: A demonstration in the Yukon River Basin of interior Alaska

    Science.gov (United States)

    Huang, Shengli; Jin, Suming; Dahal, Devendra; Chen, Xuexia; Young, Claudia; Liu, Heping; Liu, Shuguang

    2013-01-01

    Land surface change caused by fires and succession is confounded by many site-specific factors and requires further study. The objective of this study was to reveal the spatially explicit land surface change by minimizing the confounding factors of weather variability, seasonal offset, topography, land cover, and drainage. In a pilot study of the Yukon River Basin of interior Alaska, we retrieved Normalized Difference Vegetation Index (NDVI), albedo, and land surface temperature (LST) from a postfire Landsat image acquired on August 5th, 2004. With a Landsat reference image acquired on June 26th, 1986, we reconstructed NDVI, albedo, and LST of 1987–2004 fire scars for August 5th, 2004, assuming that these fires had not occurred. The difference between actual postfire and assuming-no-fire scenarios depicted the fires and succession impact. Our results demonstrated the following: (1) NDVI showed an immediate decrease after burning but gradually recovered to prefire levels in the following years, in which burn severity might play an important role during this process; (2) Albedo showed an immediate decrease after burning but then recovered and became higher than prefire levels; and (3) Most fires caused surface warming, but cooler surfaces did exist; time-since-fire affected the prefire and postfire LST difference but no absolute trend could be found. Our approach provided spatially explicit land surface change rather than average condition, enabling a better understanding of fires and succession impact on ecological consequences at the pixel level.

  12. Modeling Behavior by Coastal River Otter (Lontra Canadensis in Response to Prey Availability in Prince William Sound, Alaska: A Spatially-Explicit Individual-Based Approach.

    Directory of Open Access Journals (Sweden)

    Shannon E Albeke

    Full Text Available Effects of climate change on animal behavior and cascading ecosystem responses are rarely evaluated. In coastal Alaska, social river otters (Lontra Canadensis, largely males, cooperatively forage on schooling fish and use latrine sites to communicate group associations and dominance. Conversely, solitary otters, mainly females, feed on intertidal-demersal fish and display mutual avoidance via scent marking. This behavioral variability creates "hotspots" of nutrient deposition and affects plant productivity and diversity on the terrestrial landscape. Because the abundance of schooling pelagic fish is predicted to decline with climate change, we developed a spatially-explicit individual-based model (IBM of otter behavior and tested six scenarios based on potential shifts to distribution patterns of schooling fish. Emergent patterns from the IBM closely mimicked observed otter behavior and landscape use in the absence of explicit rules of intraspecific attraction or repulsion. Model results were most sensitive to rules regarding spatial memory and activity state following an encounter with a fish school. With declining availability of schooling fish, the number of social groups and the time simulated otters spent in the company of conspecifics declined. Concurrently, model results suggested an elevation of defecation rate, a 25% increase in nitrogen transport to the terrestrial landscape, and significant changes to the spatial distribution of "hotspots" with declines in schooling fish availability. However, reductions in availability of schooling fish could lead to declines in otter density over time.

  13. Klawock Lagoon, Alaska Benthic Habitats 2011 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  14. Klawock Lagoon, Alaska Benthic Habitats 2011 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  15. Klawock Lagoon, Alaska Benthic Habitats 2011 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  16. Klawock Lagoon, Alaska Benthic Habitats 2011 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  17. Investigations of some regional river systems by INAA and X-ray fluorescence

    International Nuclear Information System (INIS)

    Drazhkovich, R.J.; Kukoch, A.

    1985-01-01

    Distribution of Zn, Hg, Sb, Cr, Fe, Sc and Co has been investigated in materials dissolved and suspended in the rivers Ibar, Zapadna Morava and Kamenica by means of INAA and X-ray fluorescence. Irradiation was made in VKG-channels of RA-nuclear reactor Vincha. Distribution coefficients were calculated, as well as contamination factors for investigated river regional systems in comparison to the uncontaminated water system. Data obtained indicate the possibility of utilization of these two analytical methods for investigation and control of biogeochemical and contamination processes in small regional water systems, especially important for modern studies in life sciences

  18. Apatite fission-track evidence for regional exhumation in the subtropical Eocene, block faulting, and localized fluid flow in east-central Alaska

    Science.gov (United States)

    Dusel-Bacon, Cynthia; Bacon, Charles R.; O'Sullivan, Paul B.; Day, Warren C.

    2016-01-01

    The origin and antiquity of the subdued topography of the Yukon–Tanana Upland (YTU), the physiographic province between the Denali and Tintina faults, are unresolved questions in the geologic history of interior Alaska and adjacent Yukon. We present apatite fission-track (AFT) results for 33 samples from the 2300 km2 western Fortymile district in the YTU in Alaska and propose an exhumation model that is consistent with preservation of volcanic rocks in valleys that requires base level stability of several drainages since latest Cretaceous–Paleocene time. AFT thermochronology indicates widespread cooling below ∼110 °C at ∼56–47 Ma (early Eocene) and ∼44–36 Ma (middle Eocene). Samples with ∼33–27, ∼19, and ∼10 Ma AFT ages, obtained near a major northeast-trending fault zone, apparently reflect hydrothermal fluid flow. Uplift and erosion following ∼107 Ma magmatism exposed plutonic rocks to different extents in various crustal blocks by latest Cretaceous time. We interpret the Eocene AFT ages to suggest that higher elevations were eroded during the Paleogene subtropical climate of the subarctic, while base level remained essentially stable. Tertiary basins outboard of the YTU contain sediment that may account for the required >2 km of removed overburden that was not carried to the sea by the ancestral Yukon River system. We consider a climate driven explanation for the Eocene AFT ages to be most consistent with geologic constraints in concert with block faulting related to translation on the Denali and Tintina faults resulting from oblique subduction along the southern margin of Alaska.

  19. Macroinvertebrate distribution and aquatic ecology in the Ruoergai (Zoige) Wetland, the Yellow River source region

    Science.gov (United States)

    Zhao, Na; Xu, Mengzhen; Li, Zhiwei; Wang, Zhaoyin; Zhou, Hanmi

    2017-09-01

    The Ruoergai (Zoige) Wetland, the largest plateau peatland in the world, is located in the Yellow River source region. The discharge of the Yellow River increases greatly after flowing through the Ruoergai Wetland. The aquatic ecosystem of the Ruoergai Wetland is crucial to the whole Yellow River basin. The Ruoergai wetland has three main kinds of water bodies: rivers, oxbow lakes, and marsh wetlands. In this study, macroinvertebrates were used as indicators to assess the aquatic ecological status because their assemblage structures indicate long-term changes in environments with high sensitivity. Field investigations were conducted in July, 2012 and in July, 2013. A total of 72 taxa of macroinvertebrates belonging to 35 families and 67 genera were sampled and identified. Insecta was the dominant group in the Ruoergai Basin. The alpha diversity of macroinvertebrates at any single sampling site was low, while the alpha diversity on a basin-wide scale was much higher. Macroinvertebrate assemblages in rivers, oxbow lakes, and marsh wetlands differ markedly. Hydrological connectivity was a primary factor causing the variance of the bio-community. The river channels had the highest alpha diversity of macroinvertebrates, followed by marsh wetlands and oxbow lakes. The density and biomass of Gastropoda, collector filterers, and scrapers increased from rivers to oxbow lakes and then to marsh wetlands. The river ecology was particular in the Ruoergai Wetland with the high beta diversity of macroinvertebrates, the low alpha diversity of macroinvertebrates, and the low taxa richness, density, and biomass of EPT (Ephemeroptera, Plecoptera, Trichoptera). To maintain high alpha diversity of macroinvertebrates macroinvertebrates in the Ruoergai Wetland, moderate connectivity of oxbow lakes and marsh wetlands with rivers and measures to control headwater erosion are both crucial.

  20. Solute geochemistry of the Snake River Plain regional aquifer system, Idaho and eastern Oregon

    International Nuclear Information System (INIS)

    Wood, W.W.; Low, W.H.

    1987-01-01

    Three geochemical methods were used to determine chemical reactions that control solute concentrations in the Snake River Plain regional aquifer system: (1) calculation of a regional solute balance within the aquifer and of mineralogy in the aquifer framework to identify solute reactions, (2) comparison of thermodynamic mineral saturation indices with plausible solute reactions, and (3) comparison of stable isotope ratios of the groundwater with those in the aquifer framework. The geothermal groundwater system underlying the main aquifer system was examined by calculating thermodynamic mineral saturation indices, stable isotope ratios of geothermal water, geothermometry, and radiocarbon dating. Water budgets, hydrologic arguments, and isotopic analyses for the eastern Snake River Plain aquifer system demonstrate that most, if not all, water is of local meteoric and not juvenile or formation origin. Solute balance, isotopic, mineralogic, and thermodynamic arguments suggest that about 20% of the solutes are derived from reactions with rocks forming the aquifer framework. Reactions controlling solutes in the western Snake river basin are believed to be similar to those in the eastern basin but the regional geothermal system that underlies the Snake river Plain contains total dissolved solids similar to those in the overlying Snake River Plain aquifer system but contains higher concentrations of sodium, bicarbonate, silica, fluoride, sulfate, chloride, arsenic, boron, and lithium, and lower concentrations of calcium, magnesium, and hydrogen. 132 refs., 30 figs., 27 tabs

  1. Cost-effectiveness of preventing dental caries and full mouth dental reconstructions among Alaska Native children in the Yukon–Kuskokwim delta region of Alaska

    Science.gov (United States)

    Atkins, Charisma Y.; Thomas, Timothy K.; Lenaker, Dane; Day, Gretchen M.; Hennessy, Thomas W.; Meltzer, Martin I.

    2016-01-01

    Objective We conducted a cost-effectiveness analysis of five specific dental interventions to help guide resource allocation. Methods We developed a spreadsheet-based tool, from the healthcare payer perspective, to evaluate the cost effectiveness of specific dental interventions that are currently used among Alaska Native children (6-60 months). Interventions included: water fluoridation, dental sealants, fluoride varnish, tooth brushing with fluoride toothpaste, and conducting initial dental exams on children caries treatments completed by a dental provider in the dental chair, while 161 children received FMDRs completed by a dental surgeon in an operating room. The average cost of treating dental caries in the dental chair was $1,467 (~258,000 per year); while the cost of treating FMDRs was $9,349 (~1.5 million per year). All interventions were shown to prevent caries and FMDRs; however tooth brushing prevented the greatest number of caries at minimum and maximum effectiveness with 1,433 and 1,910, respectively. Tooth brushing also prevented the greatest number of FMDRs (159 and 211) at minimum and maximum effectiveness. Conclusions All of the dental interventions evaluated were shown to produce cost savings. However, the level of that cost saving is dependent on the intervention chosen. PMID:26990678

  2. Evaluating signals of oil spill impacts, climate, and species interactions in Pacific herring and Pacific salmon populations in Prince William Sound and Copper River, Alaska.

    Directory of Open Access Journals (Sweden)

    Eric J Ward

    Full Text Available The Exxon Valdez oil spill occurred in March 1989 in Prince William Sound, Alaska, and was one of the worst environmental disasters on record in the United States. Despite long-term data collection over the nearly three decades since the spill, tremendous uncertainty remains as to how significantly the spill affected fishery resources. Pacific herring (Clupea pallasii and some wild Pacific salmon populations (Oncorhynchus spp. in Prince William Sound declined in the early 1990s, and have not returned to the population sizes observed in the 1980s. Discerning if, or how much of, this decline resulted from the oil spill has been difficult because a number of other physical and ecological drivers are confounded temporally with the spill; some of these drivers include environmental variability or changing climate regimes, increased production of hatchery salmon in the region, and increases in populations of potential predators. Using data pre- and post-spill, we applied time-series methods to evaluate support for whether and how herring and salmon productivity has been affected by each of five drivers: (1 density dependence, (2 the EVOS event, (3 changing environmental conditions, (4 interspecific competition on juvenile fish, and (5 predation and competition from adult fish or, in the case of herring, humpback whales. Our results showed support for intraspecific density-dependent effects in herring, sockeye, and Chinook salmon, with little overall support for an oil spill effect. Of the salmon species, the largest driver was the negative impact of adult pink salmon returns on sockeye salmon productivity. Herring productivity was most strongly affected by changing environmental conditions; specifically, freshwater discharge into the Gulf of Alaska was linked to a series of recruitment failures-before, during, and after EVOS. These results highlight the need to better understand long terms impacts of pink salmon on food webs, as well as the

  3. Climate Drivers of Spatiotemporal Variability of Precipitation in the Source Region of Yangtze River

    Science.gov (United States)

    Du, Y.; Berndtsson, R.; An, D.; Yuan, F.

    2017-12-01

    Variability of precipitation regime has significant influence on the environment sustainability in the source region of Yangtze River, especially when the vegetation degradation and biodiversity reduction have already occurred. Understanding the linkage between variability of local precipitation and global teleconnection patterns is essential for water resources management. Based on physical reasoning, indices of the climate drivers can provide a practical way of predicting precipitation. Due to high seasonal variability of precipitation, climate drivers of the seasonal precipitation also varies. However, few reports have gone through the teleconnections between large scale patterns with seasonal precipitation in the source region of Yangtze River. The objectives of this study are therefore (1) assessment of temporal trend and spatial variability of precipitation in the source region of Yangtze River; (2) identification of climate indices with strong influence on seasonal precipitation anomalies; (3) prediction of seasonal precipitation based on revealed climate indices. Principal component analysis and Spearman rank correlation were used to detect significant relationships. A feed-forward artificial neural network(ANN) was developed to predict seasonal precipitation using significant correlated climate indices. Different influencing climate indices were revealed for precipitation in each season, with significant level and lag times. Significant influencing factors were selected to be the predictors for ANN model. With correlation coefficients between observed and simulated precipitation over 0.5, the results were eligible to predict the precipitation of spring, summer and winter using teleconnections, which can improve integrated water resources management in the source region of Yangtze River.

  4. Regional effects of agricultural conservation practices on nutrient transport in the Upper Mississippi River Basin

    Science.gov (United States)

    Garcia, Ana Maria.; Alexander, Richard B.; Arnold, Jeffrey G.; Norfleet, Lee; White, Michael J.; Robertson, Dale M.; Schwarz, Gregory E.

    2016-01-01

    Despite progress in the implementation of conservation practices, related improvements in water quality have been challenging to measure in larger river systems. In this paper we quantify these downstream effects by applying the empirical U.S. Geological Survey water-quality model SPARROW to investigate whether spatial differences in conservation intensity were statistically correlated with variations in nutrient loads. In contrast to other forms of water quality data analysis, the application of SPARROW controls for confounding factors such as hydrologic variability, multiple sources and environmental processes. A measure of conservation intensity was derived from the USDA-CEAP regional assessment of the Upper Mississippi River and used as an explanatory variable in a model of the Upper Midwest. The spatial pattern of conservation intensity was negatively correlated (p = 0.003) with the total nitrogen loads in streams in the basin. Total phosphorus loads were weakly negatively correlated with conservation (p = 0.25). Regional nitrogen reductions were estimated to range from 5 to 34% and phosphorus reductions from 1 to 10% in major river basins of the Upper Mississippi region. The statistical associations between conservation and nutrient loads are consistent with hydrological and biogeochemical processes such as denitrification. The results provide empirical evidence at the regional scale that conservation practices have had a larger statistically detectable effect on nitrogen than on phosphorus loadings in streams and rivers of the Upper Mississippi Basin.

  5. Regional Effects of Agricultural Conservation Practices on Nutrient Transport in the Upper Mississippi River Basin.

    Science.gov (United States)

    García, Ana María; Alexander, Richard B; Arnold, Jeffrey G; Norfleet, Lee; White, Michael J; Robertson, Dale M; Schwarz, Gregory

    2016-07-05

    Despite progress in the implementation of conservation practices, related improvements in water quality have been challenging to measure in larger river systems. In this paper we quantify these downstream effects by applying the empirical U.S. Geological Survey water-quality model SPARROW to investigate whether spatial differences in conservation intensity were statistically correlated with variations in nutrient loads. In contrast to other forms of water quality data analysis, the application of SPARROW controls for confounding factors such as hydrologic variability, multiple sources and environmental processes. A measure of conservation intensity was derived from the USDA-CEAP regional assessment of the Upper Mississippi River and used as an explanatory variable in a model of the Upper Midwest. The spatial pattern of conservation intensity was negatively correlated (p = 0.003) with the total nitrogen loads in streams in the basin. Total phosphorus loads were weakly negatively correlated with conservation (p = 0.25). Regional nitrogen reductions were estimated to range from 5 to 34% and phosphorus reductions from 1 to 10% in major river basins of the Upper Mississippi region. The statistical associations between conservation and nutrient loads are consistent with hydrological and biogeochemical processes such as denitrification. The results provide empirical evidence at the regional scale that conservation practices have had a larger statistically detectable effect on nitrogen than on phosphorus loadings in streams and rivers of the Upper Mississippi Basin.

  6. 76 FR 58533 - Powder River Regional Coal Team Activities; Notice of Public Meeting in Casper, WY

    Science.gov (United States)

    2011-09-21

    ... meeting is open to the public. ADDRESSES: The meeting will be held at the Wyoming Oil and Gas Conservation... Right Lease Applications in New Mexico held by Ark Land Company, for competitive bidding rights in... Powder River Coal Production Region. Any party interested in providing comments or data related to...

  7. About temporal evolution of the geomagnetic field in the River Plate region

    International Nuclear Information System (INIS)

    Gianibelli, J.; Quaglino, L.

    2010-01-01

    Permanent Observatories network allows to study the total intensity of the magnetic field of the Earth surface to assess its annual change and inductive effects on networks of large pipes and pipelines. This paper is about the results of the significant decline in the River Plate region. The effects observed in this surface anomaly continue amplified and reaching minimum values

  8. Dissolved nitrogen in rivers: comparing pristine and impacted regions of Brazil

    Directory of Open Access Journals (Sweden)

    LA Martinelli

    Full Text Available Riverine nitrogen distribution is increasingly controlled by anthropogenic activities in their watersheds, regardless of spatial scale, climate, and geographical zone. Consequently, modelling efforts to predict the export of nitrogen from rivers worldwide have used attributes such as population density, land use, urbanization and sanitation. These models have greatly enhanced our understanding of the sources and fate of nitrogen added to terrestrial systems and transported to rivers and streams, especially for developed countries of the North temperate zone. However, much of the world's population lives in developing countries of the tropics, where the effects of human activities on riverine N exports are still poorly understood. In an effort to close this gap, we compare riverine nitrogen data from 32 Brazilian rivers draining two contrasting regions in this tropical country in terms of economic development - the State of São Paulo and the Amazon. Our data include nitrogen in different dissolved forms, such as Dissolved Inorganic Nitrogen (DIN and Dissolved Organic Nitrogen (DON. The results show that nitrogen concentrations decreased as river runoff increased in both study areas, and that concentrations were significantly higher in rivers draining the most economically developed region. The relationships between nitrogen concentrations and fluxes with demographic parameters such as population density were also determined and compared to those in temperate systems. In contrast to temperate watersheds, we found that nitrogen fluxes increased only after population densities were higher than 10 individuals per km².

  9. Chemical composition of black-watered rivers in the Amazons Region (Brazil)

    International Nuclear Information System (INIS)

    Horbe, Adriana M.C.; Santos, Ana G. da Silva

    2009-01-01

    Most investigations addressing Amazonian water chemistry are focused on the Solimoes, Amazonas and Negro rivers. Knowledge of the chemical composition of their smaller tributaries is restricted to some few, punctual data. The smaller rivers, that only present inputs from their catchments, are very important to understand the overall mechanisms controlling the chemistry of larger rivers of the region. With this objective the chemical composition of the principal Solimoes river black-watered tributaries in the western Brazilian Amazon during the low water period were determined. The data reveal the black water chemical composition to be highly variable and strongly influenced by the local geological environment: the Badajos basin being chemically more diluted; the Coari basin presenting higher SiO 2 contents, as well as smaller lakes having higher pH, conductivity, Ca 2+ , Mg 2+ and Sr, yet not as much as those found in the Solimoes river. The chemical composition of these waters is compatible with the low physical erosion and the region's highly leached tropical environment from which most soluble elements were quickly removed. (author)

  10. Ground-water resources in the tri-state region adjacent to the Lower Delaware River

    Science.gov (United States)

    Barksdale, Henry C.; Greenman, David W.; Lang, Solomon Max; Hilton, George Stockbridge; Outlaw, Donald E.

    1958-01-01

    The purpose of this report is to appraise and evaluate the groundwater resources of a tri-state region adjacent to the lower Delaware River that is centered around Philadelphia, Pa., and Camden, N. J., and includes Wilmington, Del., and Trenton, N.J. Specifically, the region includes New Castle County, Del.; Burlington, Camden, Gloucester, Mercer, and Salem Counties in New Jersey; and Bucks, Chester, Delaware, Montgomery, and Philadelphia Counties in Pennsylvania.

  11. U.S. Geological Survey 2011 assessment of undiscovered oil and gas resources of the Cook Inlet region, south-central Alaska

    Science.gov (United States)

    Stanley, Richard G.; Pierce, Brenda S.; Houseknecht, David W.

    2011-01-01

    The U.S. Geological Survey (USGS) has completed an assessment of the volumes of undiscovered, technically recoverable oil and gas resources in conventional and continuous accumulations in Cook Inlet. The assessment used a geology-based methodology and results from new scientific research by the USGS and the State of Alaska, Department of Natural Resources, Division of Geological and Geophysical Surveys and Division of Oil and Gas (DOG). In the Cook Inlet region, the USGS estimates mean undiscovered volumes of nearly 600 million barrels of oil, about 19 trillion cubic feet of gas, and about 46 million barrels of natural gas liquids.

  12. Heavy metals in the small rivers of Ternopil region under different types of anthropogenic pressure

    Directory of Open Access Journals (Sweden)

    O. Prokopchuk

    2016-03-01

    Full Text Available The dynamic of content and peculiarities of migration of heavy metals in small rivers of Ternopil region were analyzed (Zn, Mn, Fe, Co, Ni, Pb. It was determined that cobalt does not exceed maximum permissible levels, whereas the content of other metals exceed these levels at rates from 2 to 42 times the emission limit set by the fishing industry. The waters of Ternopil region are the richest in the compounds of iron and manganese by virtue of the lithological content of the researched water basins. The excess in Mn and Fe concentration in river water is caused by occurrence of these elements in abiotic components of river valleys, particularly in areas with iron and manganese, alluvial deposits, clay soils with ferrous metal compounds and leaching of elements from rock, soil and forest litter. As our research showed, increased metal content in water basins is caused by natural factors (river running through areas with ore and where leaching of ore occurs it, reaction of interstitial water, metals appearing in ground water run-off, anthropogenic (waste waters of industrial plants, agricultural outwash, fuel combustion and hydrochemical factors of the hydroecosystem itself (consumption and releasing of metals by hydrobionts, aquatic habitat pH, metals coming in from ground sediments, metals released from complexes with organic compounds, methylation of non-organic metal compounds. A comparative analysis of the pollution levels of Ternopil region water basins by heavy metals was completed. It was determined that the river most heavily contaminated by the content of nutrients and non-biogenic HM is the Zolota Lypa and the cleanest is the River Strypa, which allows us to recommend the use of water composition as a reference indicator in assessing the ecological state of the region’s surface waters.

  13. Visitor, State of Alaska

    Science.gov (United States)

    /Fishing License Get a Birth Certificate, Marriage License, etc. Alaska Permanent Fund Dividend Statewide Library Alaska Historical Society Alaska State Museum Sheldon Jackson Museum Industry Facts Agriculture

  14. 2005 Alaska Division of Geological & Geophysical Surveys Lidar: Unalakleet, Alaska

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This report is a summary of a LiDAR data collection over the community of Unalakleet, in the Norton Sound region of Alaska. The original data were collected on...

  15. Reemergence of rabies in the southern Han river region, Korea.

    Science.gov (United States)

    Oem, Jae-Ku; Kim, Seong-Hee; Kim, Yeon-Hee; Lee, Myoung-Heon; Lee, Kyoung-Ki

    2014-07-01

    Recently, 11 cases of animal rabies were reported in the southern region (Suwon and Hwaseong cities) of Gyeonggi Province, South Korea. The cases were temporally separated into two cases in dogs (Canis lupus familiaris) in spring 2012 and nine cases in domestic animals and wildlife in winter 2012-13. All carcasses were submitted for histopathologic examination and viral antigen identification. Sequences of the glycoprotein, nucleoprotein, and glycoprotein-large polymerase protein intergenic noncoding loci of the 11 strains were determined and compared with published reference sequences. All rabies strains were closely related to the Gangwon strains isolated in 2008-09, suggesting that the rabies virus strains isolated in Gyeonggi were introduced from Gangwon Province.

  16. Assessment of Water Quality of Subarnarekha River in Balasore Region, Odisha, India

    OpenAIRE

    A. A Karim; R. B Panda

    2014-01-01

    The present study was carried out to determine the water quality status of Subarnarekha River at Balasore region during pre-project period as Kirtania Port is proposed in this area. River water samples were analysed for physico-chemical parameters by following standard methods (APHA 1985) and the results showed their variations as follows: pH 7.3-7.8,Temperature 26.7-28.20C, Electrical Conductivity 392-514 µ mho ,Total suspended solids 118-148 mg/l, Total dissolved solids 241-285 mg/l, Alkali...

  17. Supervising Scientist for the Alligator Rivers Region Annual Report 1996-1997

    International Nuclear Information System (INIS)

    1997-01-01

    One of the most significant developments during the year was the submission by Energy Resources of Australia Ltd of its Environmental Impact Statement for Jabiluka. The proposal is significantly different in technical detail from the Ranger and Nabarlek mines owing to the proposal to mine underground. Evaluation of the Environmental Performance of the uranium mines of the Alligator Rivers Region continued, with twice-yearly Environmental Performance Reviews (EPR) of Ranger and Nabarlek, and results reported to the Alligator Rivers Region Advisory Committee (ARRAC). Ongoing technical consultations took place through meetings of the Ranger Minesite Technical Committee. Issues relating to water disposal were addressed through the Ranger Water Management Working Group. Submissions were made regarding the Jabiluka Environmental Impact Assessment process and technical advice was provided to the Environmental Assessment Branch of Environment Australia during the assessment. The organisation's research program has reflected strategic directions set last year by the Alligator Rivers Region Technical Committee (ARRTC) concerning environmental impacts of mining. Key projects assess radiation exposure by members of the public as a result of uranium mining, the effectiveness of artificial wetlands in the treatment of mine waters, and the development of methods to assess the effectiveness of options for rehabilitation. Development of the research program into wetlands protection and management continued, including establishment of a coordinated monitoring program to measure and assess coastal change as a benchmark for monitoring effects of climate change in the Alligator Rivers Region (a key part of a national network). Other research activities included water quality research for the National River Health Program and revision of the National Water Quality Management Strategy, Water Quality Guidelines for Fresh and Marine Waters and conclusion of research projects in the Mount

  18. Uranium hydrogeochemical and stream sediment reconnaissance data from the area of the Noatak and portions of the Baird Mountains and Ambler River Quadrangles, Alaska

    International Nuclear Information System (INIS)

    Aamodt, P.L.; Hill, D.E.; Sharp, R.R. Jr.

    1978-05-01

    During August 1976, a total of 876 natural waters and 861 bottom sediments were collected at a nominal density of one location each 23 km 2 from streams and small lakes throughout the Noatak NTMS quadrangle, the southern two-thirds of the Baird Mountains NTMS quadrangle, and in the southwest corner of the Ambler River NTMS quadrangle. These samples were collected as part of the National Uranium Resource Evaluation program in Alaska being conducted by the Los Alamos Scientific Laboratory (LASL). The field collection and treatment of the samples were performed following strict LASL specifications. Total uranium was measured in the waters by fluorometry and in the sediments by delayed-neutron counting, using stringent quality assurance controls at the LASL. The uranium contents of the waters ranged from below the detection limit of 0.02 parts per billion (ppB) to a high of 8.38 ppB, and the uranium contents of the sediments ranged from a low of 0.3 parts per million (ppM) to a high of 34.0 ppM. In general, the locations of waters containing relatively high uranium contents were found to occur in clusters, and particularly in the headwaters of streams draining the southern slopes of the Baird Mountains. Few sediments contained relatively high uranium contents. These usually occurred singly at isolated locations scattered throughout the area. No obvious association exists between the location of high-uranium waters and sediments anywhere in the study area. The geology, mineralogy, and hydrology of this area is only generally described in the literature; therefore, it is difficult to correlate these data with particular aspects of the physical environment where individual samples were collected. However, the data do indicate that certain areas underlaid by Paleozoic sedimentary rocks and granitic intrusives within the Baird Mountains and a quartz-pebble conglomerate in the Waring Mountains may warrant more detailed field investigations

  19. Columbia River System Operation Review final environmental impact statement. Appendix Q: Regional forum

    International Nuclear Information System (INIS)

    1995-11-01

    The System Operation Review (SOR) is a study and environmental compliance process being used by the three Federal agencies to analyze future operations of the system and river use issues. The goal of the SOR is to achieve a coordinated system operation strategy for the river that better meets the needs of all river users. This technical appendix addresses only the effects of alternative system operating strategies for managing the Columbia River system. The SOR is currently developing a System Operating Strategy (SOS) that will guide the physical operations of the Columbia River system. The SOR is also addressing the institutional arrangements that must be in place to make needed changes to the SOS in the future, or make interpretations of the strategy in the light of changing water conditions or river needs. For convenience, this future institutional arrangement is referred to as ''The Columbia River Regional Forum,'' or simply ''the Forum,'' even though the nature of this institution is still to be determined. This appendix and the Final Environmental Impact Statement (EIS) identify the Forum as an administrative process that will not result in impacts to the environment and will not require analysis in a NEPA context. The composition of and procedures followed by a decision making body cannot--in and of themselves--be used to predict a particular decision with definable impacts on the environment. Nevertheless, because of the relationship to the other SOR actions, the SOR lead agencies have prepared this Technical Appendix to provide opportunities for review and comment on the Forum alternatives

  20. Punctuated Sediment Discharge during Early Pliocene Birth of the Colorado River: Evidence from Regional Stratigraphy, Sedimentology, and Paleontology

    Science.gov (United States)

    Dorsey, Rebecca J.; O'Connell, Brennan; McDougall, Kristin; Homan, Mindy B.

    2018-01-01

    The Colorado River in the southwestern U.S. provides an excellent natural laboratory for studying the origins of a continent-scale river system, because deposits that formed prior to and during river initiation are well exposed in the lower river valley and nearby basinal sink. This paper presents a synthesis of regional stratigraphy, sedimentology, and micropaleontology from the southern Bouse Formation and similar-age deposits in the western Salton Trough, which we use to interpret processes that controlled the birth and early evolution of the Colorado River. The southern Bouse Formation is divided into three laterally persistent members: basal carbonate, siliciclastic, and upper bioclastic members. Basal carbonate accumulated in a tide-dominated marine embayment during a rise of relative sea level between 6.3 and 5.4 Ma, prior to arrival of the Colorado River. The transition to green claystone records initial rapid influx of river water and its distal clay wash load into the subtidal marine embayment at 5.4-5.3 Ma. This was followed by rapid southward progradation of the Colorado River delta, establishment of the earliest through-flowing river, and deposition of river-derived turbidites in the western Salton Trough (Wind Caves paleocanyon) between 5.3 and 5.1 Ma. Early delta progradation was followed by regional shut-down of river sand output between 5.1 and 4.8 Ma that resulted in deposition of marine clay in the Salton Trough, retreat of the delta, and re-flooding of the lower river valley by shallow marine water that deposited the Bouse upper bioclastic member. Resumption of sediment discharge at 4.8 Ma drove massive progradation of fluvial-deltaic deposits back down the river valley into the northern Gulf and Salton Trough. These results provide evidence for a discontinuous, start-stop-start history of sand output during initiation of the Colorado River that is not predicted by existing models for this system. The underlying controls on punctuated sediment

  1. Study of a conceptual nuclear energy center at Green River, Utah: regional considerations

    International Nuclear Information System (INIS)

    1982-01-01

    This document constitutes one segment of a feasibility study investigating the ramifications of constructing a nuclear energy center in an arid and remote Western region. This phase of the study discusses regional considerations involved in nuclear energy center development at Green River, Utah. Regional support for NEC development is assessed. In addition, possible regulatory constraints to NEC development are identified and analyzed. Possible resource allocation shortages resulting from NEC development are also considered. A comparison with a similar study on NEC development in the Southeastern United States is also included

  2. Climatic Atlas of the Outer Continental Shelf Waters and Coastal Regions of Alaska. Volume 2. Bering Sea. Revision

    Science.gov (United States)

    1988-01-01

    Joe D. Elms , for their editorial evaluation of the vironmental Assessmant Program. Additional depends to a large extent on weather condi- isopleth...waves, icing rates are open waters and coastal sectionsofAlaska.The temperatures less than 8°C, winds of 25 knots lower. icing causes slippery decks...thereby bias the oceanic climatology towards fair weather. A recent study by Elms (1986), in which he compared the Volunteer Observing Ship (VOS) data

  3. Identifying hotspots and management of critical ecosystem services in rapidly urbanizing Yangtze River Delta Region, China.

    Science.gov (United States)

    Cai, Wenbo; Gibbs, David; Zhang, Lang; Ferrier, Graham; Cai, Yongli

    2017-04-15

    Rapid urbanization has altered many ecosystems, causing a decline in many ecosystem services, generating serious ecological crisis. To cope with these challenges, we presented a comprehensive framework comprising five core steps for identifying and managing hotspots of critical ecosystem services in a rapid urbanizing region. This framework was applied in the case study of the Yangtze River Delta (YRD) Region. The study showed that there was large spatial heterogeneity in the hotspots of ecosystem services in the region, hotspots of supporting services and regulating services aggregately distributing in the southwest mountainous areas while hotspots of provisioning services mainly in the northeast plain, and hotspots of cultural services widespread in the waterbodies and southwest mountainous areas. The regionalization of the critical ecosystem services was made through the hotspot analysis. This study provided valuable information for environmental planning and management in a rapid urbanizing region and helped improve China's ecological redlines policy at regional scale. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Run-of-river power plants in Alpine regions: whither optimal capacity?

    Science.gov (United States)

    Lazzaro, Gianluca; Botter, Gianluca

    2015-04-01

    Hydropower is the major renewable electricity generation technology worldwide. The future expansion of this technology mostly relies on the development of small run-of-river projects, in which a fraction of the running flows is diverted from the river to a turbine for energy production. Even though small hydro inflicts a smaller impact on aquatic ecosystems and local communities compared to large dams, it cannot prevent stresses on plant, animal, and human well-being. This is especially true in mountain regions where the plant outflow is located several kilometers downstream of the intake, thereby inducing the depletion of river reaches of considerable length. Moreover, the negative cumulative effects of run-of-river systems operating along the same river threaten the ability of stream networks to supply ecological corridors for plants, invertebrates or fishes, and support biodiversity. Research in this area is severely lacking. Therefore, the prediction of the long-term impacts associated to the expansion of run-of-river projects induced by global-scale incentive policies remains highly uncertain. This contribution aims at providing objective tools to address the preliminary choice of the capacity of a run-of-river hydropower plant when the economic value of the plant and the alteration of the flow regime are simultaneously accounted for. This is done using the concepts of Pareto-optimality and Pareto-dominance, which are powerful tools suited to face multi-objective optimization in presence of conflicting goals, such as the maximization of the profitability and the minimization of the hydrologic disturbance induced by the plant in the river reach between the intake and the outflow. The application to a set of case studies belonging to the Piave River basin (Italy) suggests that optimal solutions are strongly dependent the natural flow regime at the plant intake. While in some cases (namely, reduced streamflow variability) the optimal trade-off between economic

  5. Regional implications of heat flow of the Snake River Plain, Northwestern United States

    Science.gov (United States)

    Blackwell, D. D.

    1989-08-01

    The Snake River Plain is a major topographic feature of the Northwestern United States. It marks the track of an upper mantle and crustal melting event that propagated across the area from southwest to northeast at a velocity of about 3.5 cm/yr. The melting event has the same energetics as a large oceanic hotspot or plume and so the area is the continental analog of an oceanic hotspot track such as the Hawaiian Island-Emperor Seamount chain. Thus, the unique features of the area reflect the response of a continental lithosphere to a very energetic hotspot. The crust is extensively modified by basalt magma emplacement into the crust and by the resulting massive rhyolite volcanism from melted crustal material, presently occurring at Yellowstone National Park. The volcanism is associated with little crustal extension. Heat flow values are high along the margins of the Eastern and Western Snake River Plains and there is abundant evidence for low-grade geothermal resources associated with regional groundwater systems. The regional heat flow pattern in the Western Snake River Plains reflects the influence of crustal-scale thermal refraction associated with the large sedimentary basin that has formed there. Heat flow values in shallow holes in the Eastern Snake River Plains are low due to the Snake River Plains aquifer, an extensive basalt aquifer where water flow rates approach 1 km/yr. Below the aquifer, conductive heat flow values are about 100 mW m -2. Deep holes in the region suggest a systematic eastward increase in heat flow in the Snake River Plains from about 75-90 mW m -2 to 90-110 mW m -2. Temperatures in the upper crust do not behave similarly because the thermal conductivity of the Plio-Pleistocene sedimentary rocks in the west is lower than that in the volcanic rocks characteristic of the Eastern Snake River Plains. Extremely high heat loss values (averaging 2500 mW m -2) and upper crustal temperatures are characteristic of the Yellowstone caldera.

  6. Regional transport of radioxenon released from the Chalk River Laboratories medical isotope facility

    International Nuclear Information System (INIS)

    Christine Johnson; Steven Biegalski

    2015-01-01

    An examination of proposed sampling sites near Chalk River Laboratories in Ontario, Canada is performed by considering the regional transport of radioxenon using atmospheric dispersion modeling. The local geography is considered, as are the local meteorological conditions during the summer months. In particular the impacts of predicted conditions on the imprinting of atmospheric radioxenon into the subsurface are considered and weighed against site proximity, geography, and geology. (author)

  7. Management of regional German river catchments (REGFLUD) impact of nitrogen reduction measures on the nitrogen load in the River Ems and the River Rhine.

    Science.gov (United States)

    Kunkel, R; Bogena, H; Goemann, H; Kreins, P; Wendland, F

    2005-01-01

    The REGFLUD-project, commissioned by Germany's Federal Research Ministry (BMBF), addresses the problem of reducing diffuse pollution from agricultural production. The objective of the project is the development and application of multi-criteria scientific methods, which are able to predict diffuse pollution in river basins subject to economic feasibility and social acceptability. The selected river basins (Ems and Rhine basins) cover a variety of landscape units with different hydrological, hydrogeological and socio-economic characteristics. This paper focuses on the analysis of the effects of certain policy measures to reduce diffuse pollution by nitrogen. For this purpose a model system consisting of an agricultural sector model, a water balance model and a residence time/denitrification model was developed and applied. First results indicate a wide range of annual nitrogen surpluses for the rural areas between less than 10 kg N/ha up to 200 kg N/ha or more depending on the type and intensity of farming. Compared to the level of nitrogen surpluses the level of nitrogen inputs into the surface waters is relatively moderate because of degradation processes during transport in soil and groundwater. Policy impact analysis for a nitrogen tax and a limitation of the livestock density stress the importance of regionally tailored measures.

  8. Uranium Hydrogeochemical and Stream Sediment Reconnaissance data from the area of the Teller, Bendeleben, Candle, and Kateel River Quadrangles, Seward Peninsula and vicinity, Alaska

    International Nuclear Information System (INIS)

    Sharp, R.R. Jr.; Hill, D.E.

    1978-05-01

    During July-August 1976, 2026 natural waters and 2085 bottom sediments were collected from 2209 sample locations (at a nominal density of one location each 23 km 2 ) on streams and small lakes throughout the Teller, Bendeleben, Candle, and western one-third of the Kateel River NTMS quadrangles, Alaska. Total uranium was measured in the waters by fluorometry and in the sediments and a few waters by delayed-neutron counting. The uranium content of the waters ranged from below the detection limit of 0.02 parts per billion (ppB) to a high of 14.50 ppB, averaging 0.44 ppB, and that of the sediments ranged from a low of 0.2 parts per million (ppM) to a high of 107.4 ppM, averaing 3.93 ppM. The uranium data for water and sediment are separately presented--as computer listings that include pertinent field measurements from each location, as graphically portrayed concentration overlays at 1:250,000 scale for each quadrangle, and as reduced figures showing contours drawn at various concentration levels for each quadrangle--and their areal distributions are compared and correlated with the known features and uranium showings. A test of increasingly detailed methods of data evaluation shows that the more extensive the evaluation, the more useful the reconnaissance uranium data are likely to be. The validity and potential usefulness of the HSSR uranium data are conclusively substantiated by the fact that evidence of all 23 of the reported uranium showings in the 50,000-km 2 study area can be discerned. Several new locations of interest for further field investigation are identified in each of the quadrangles, and most notably in the Bendeleben Mountains. However, the data presented would appear equally useful in guiding field investigation around the uranium occurrences already known, as noteworthy samples often come from close by but on tributary drainages adjacent, opposite, or above them

  9. The EO-1 hyperion and advanced land imager sensors for use in tundra classification studies within the Upper Kuparuk River Basin, Alaska

    Science.gov (United States)

    Hall-Brown, Mary

    The heterogeneity of Arctic vegetation can make land cover classification vey difficult when using medium to small resolution imagery (Schneider et al., 2009; Muller et al., 1999). Using high radiometric and spatial resolution imagery, such as the SPOT 5 and IKONOS satellites, have helped arctic land cover classification accuracies rise into the 80 and 90 percentiles (Allard, 2003; Stine et al., 2010; Muller et al., 1999). However, those increases usually come at a high price. High resolution imagery is very expensive and can often add tens of thousands of dollars onto the cost of the research. The EO-1 satellite launched in 2002 carries two sensors that have high specral and/or high spatial resolutions and can be an acceptable compromise between the resolution versus cost issues. The Hyperion is a hyperspectral sensor with the capability of collecting 242 spectral bands of information. The Advanced Land Imager (ALI) is an advanced multispectral sensor whose spatial resolution can be sharpened to 10 meters. This dissertation compares the accuracies of arctic land cover classifications produced by the Hyperion and ALI sensors to the classification accuracies produced by the Systeme Pour l' Observation de le Terre (SPOT), the Landsat Thematic Mapper (TM) and the Landsat Enhanced Thematic Mapper Plus (ETM+) sensors. Hyperion and ALI images from August 2004 were collected over the Upper Kuparuk River Basin, Alaska. Image processing included the stepwise discriminant analysis of pixels that were positively classified from coinciding ground control points, geometric and radiometric correction, and principle component analysis. Finally, stratified random sampling was used to perform accuracy assessments on satellite derived land cover classifications. Accuracy was estimated from an error matrix (confusion matrix) that provided the overall, producer's and user's accuracies. This research found that while the Hyperion sensor produced classfication accuracies that were

  10. Application of HEC-RAS for flood forecasting in perched river-A case study of hilly region, China

    Science.gov (United States)

    Sun, Pingping; Wang, Shuqian; Gan, Hong; Liu, Bin; Jia, Ling

    2017-04-01

    Flooding in small and medium rivers are seriously threatening the safety of human beings’ life and property. The simulation forecasting of the river flood and bank risk in hilly region has gradually become a hotspot. At present, there are few studies on the simulation of hilly perched river, especially in the case of lacking section flow data. And the method of how to determine the position of the levee breach along the river bank is not much enough. Based on the characteristics of the sections in hilly perched river, an attempt is applied in this paper which establishes the correlation between the flow profile computed by HEC-RAS model and the river bank. A hilly perched river in Lingshi County, Shanxi Province of China, is taken as the study object, the levee breach positions along the bank are simulated under four different design storm. The results show that the flood control standard of upper reach is high, which can withstand the design storm of 100 years. The current standard of lower reach is low, which is the flooding channel with high frequency. As the standard of current channel between the 2rd and the 11th section is low, levee along that channel of the river bank is considered to be heighten and reinforced. The study results can provide some technical support for flood proofing in hilly region and some reference for the reinforcement of river bank.

  11. International Trade, Pollution Accumulation and Sustainable Growth: A VAR Estimation from the Pearl River Delta Region

    Science.gov (United States)

    Zuo, Hui; Tian, Lu

    2018-03-01

    In order to investigate international trade influence in the regional environment. This paper constructs a vector auto-regression (VAR) model and estimates the equations with the environment and trade data of the Pearl River Delta Region. The major mechanisms to the lag are discussed and the fit simulation of the environmental change by the international impulse is given. The result shows that impulse of pollution-intensive export deteriorates the environment continuously and impulse of such import improves it. These effects on the environment are insignificantly correlated with contemporary regional income but significantly correlative to early-stage trade feature. To a typical trade-dependent economy, both export and import have hysteresis influence in the regional environment. The lagged impulse will change environmental development in the turning point, maximal pollution level and convergence.

  12. Mercury and arsenic in the gold mining regions of the Ankobra River basin in Ghana

    Science.gov (United States)

    Bannerman, W.; Potin-Gautier, M.; Amoureux, D.; Tellier, S.; Rambaud, A.; Babut, M.; Adimado, A.; Beinhoff, C.

    2003-05-01

    The river Ankobra flows through the principal gold mining centres in Western Ghana, draining a total area of 8272 km^2 to join the Atlantic ocean. Mercury is used by thousands of small-scale miners in the region to amalgamate gold. Ores mined in some deep shafts and surface mines are arsenopyrites and the region is marked by the presence of heaps of arsenic - rich mine tailings from both past and recent activities. This study was conducted to assess the impact of mining activities on the distribution and speciation of arsenic and mercury in the aquatic environment of the Ankobra River. In all, water (filtered and non-filtered) and bed sediments were collected from various locations within the watershed. Principal parameters investigated include total mercury, arsenic (III), arsenic (V), monomethylarsonic acid (MMAA) and dimethylarsinic acid (DMAA). Seasonal and spatial variations of these parameters were investigated. Quality control systems were adopted at both the environmental and analytical stages of the study. ln general, areas close to the mining centres are the most pollilited. As (V)/As (III) ratios in water are reversed after the first 100-km of the river length with the onset of industrial influence downstream.

  13. Population structure and genetic diversity of Sinibrama macrops from Ou River and Ling River based on mtDNA D-loop region analysis, China.

    Science.gov (United States)

    Zhao, Liangjie; Chenoweth, Erica L; Liu, Qigen

    2018-03-01

    In order to understand the influence of human activities such as habitat fragmentation on freshwater fish population evolution, we investigated and compared the genetic diversity and phylogeography of Sinibrama macrops populations in the Oujiang River and Ling River. Mitochondrial control region sequences (D-loop region) of 131 specimens from six populations were obtained and analyzed. The diversity of main stream in the Ou River was lower than that in Ling River. Changtan population showed the lowest diversity (H = 0.646 ± 0.077; π = 0.00060 ± 0.00820). Pairwise F ST , gene flow (Nm), and genetic distance (Da) indicated that Longquan and Changtan significantly differentiate from other populations. Nested clade phylogeographical analysis (NCPA) showed some clades and total cladogram experienced isolation by distance. In conclusion, the populations from severely fragmented Ou River have the lower diversity and more intense differentiation than that from the mainstream of Ling River, Changtan population present the lowest diversity and were isolated by the dam construction.

  14. Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology

    Science.gov (United States)

    Dorsey, Rebecca J.; O’Connell, Brennan; McDougall-Reid, Kristin; Homan, Mindy B.

    2018-01-01

    The Colorado River in the southwestern U.S. provides an excellent natural laboratory for studying the origins of a continent-scale river system, because deposits that formed prior to and during river initiation are well exposed in the lower river valley and nearby basinal sink. This paper presents a synthesis of regional stratigraphy, sedimentology, and micropaleontology from the southern Bouse Formation and similar-age deposits in the western Salton Trough, which we use to interpret processes that controlled the birth and early evolution of the Colorado River. The southern Bouse Formation is divided into three laterally persistent members: basal carbonate, siliciclastic, and upper bioclastic members. Basal carbonate accumulated in a tide-dominated marine embayment during a rise of relative sea level between ~ 6.3 and 5.4 Ma, prior to arrival of the Colorado River. The transition to green claystone records initial rapid influx of river water and its distal clay wash load into the subtidal marine embayment at ~ 5.4–5.3 Ma. This was followed by rapid southward progradation of the Colorado River delta, establishment of the earliest through-flowing river, and deposition of river-derived turbidites in the western Salton Trough (Wind Caves paleocanyon) between ~ 5.3 and 5.1 Ma. Early delta progradation was followed by regional shut-down of river sand output between ~ 5.1 and 4.8 Ma that resulted in deposition of marine clay in the Salton Trough, retreat of the delta, and re-flooding of the lower river valley by shallow marine water that deposited the Bouse upper bioclastic member. Resumption of sediment discharge at ~ 4.8 Ma drove massive progradation of fluvial-deltaic deposits back down the river valley into the northern Gulf and Salton Trough.These results provide evidence for a discontinuous, start-stop-start history of sand output during initiation of the Colorado River that is not predicted by existing models for this system. The underlying controls on

  15. K-Ar geochronology of the Survey Pass, Ambler River and Eastern Baird Mountains quadrangles, southwestern Brooks Range, Alaska

    Science.gov (United States)

    Turner, Donald L.; Forbes, R.B.; Mayfield, C.F.

    1978-01-01

    We report 76 previously unpublished K-Ar mineral ages from 47 metamorphic and igneous rocks in the southwestern Brooks Range. The pattern of radiometric ages is complex, reflecting the complex geologic history of this area. Local and regional radiometric evidence suggests that the southern Brooks Range schist belt has, at least in part, undergone a late Precambrian metamorphism and that the parent sedimentary and igneous rocks for the metamorphic rocks dated as late Precambrian are at least this old (Precambrian Z). This schist terrane experienced a major thermal event in mid-Cretaceous time, causing widespread resetting of nearly all K-Ar mica ages. A series of apparent ages intermediate between late Precambrian and mid-Cretaceous are interpreted as indicating varying amounts of partial argon loss from older rocks during the Cretaceous event. The schist belt is characterized by dominant metasediments and subordinate metabasites and metafelsites. Blueschists occur within the schist belt from the Chandalar quadrangle westward to the Baird Mountains quadrangle, but geologic evidence does not support the existence of a fossil subduction zone.

  16. A Study on Regional Frequency Analysis using Artificial Neural Network - the Sumjin River Basin

    Science.gov (United States)

    Jeong, C.; Ahn, J.; Ahn, H.; Heo, J. H.

    2017-12-01

    Regional frequency analysis means to make up for shortcomings in the at-site frequency analysis which is about a lack of sample size through the regional concept. Regional rainfall quantile depends on the identification of hydrologically homogeneous regions, hence the regional classification based on hydrological homogeneous assumption is very important. For regional clustering about rainfall, multidimensional variables and factors related geographical features and meteorological figure are considered such as mean annual precipitation, number of days with precipitation in a year and average maximum daily precipitation in a month. Self-Organizing Feature Map method which is one of the artificial neural network algorithm in the unsupervised learning techniques solves N-dimensional and nonlinear problems and be shown results simply as a data visualization technique. In this study, for the Sumjin river basin in South Korea, cluster analysis was performed based on SOM method using high-dimensional geographical features and meteorological factor as input data. then, for the results, in order to evaluate the homogeneity of regions, the L-moment based discordancy and heterogeneity measures were used. Rainfall quantiles were estimated as the index flood method which is one of regional rainfall frequency analysis. Clustering analysis using SOM method and the consequential variation in rainfall quantile were analyzed. This research was supported by a grant(2017-MPSS31-001) from Supporting Technology Development Program for Disaster Management funded by Ministry of Public Safety and Security(MPSS) of the Korean government.

  17. Fiscal Year 1988 program report: Alaska Water Research Center

    International Nuclear Information System (INIS)

    Kane, D.L.

    1990-01-01

    The contents of this study includes: water problems and issues of Alaska; program goals and priorities; research project synopses are: radium levels in, and removal from, ground waters of interior alaska; assessment of stream-flow sediment transport for engineering projects; productivity within deep glacial gravels under subarctic Alaska rivers; nitrogen-cycle dynamics in a subarctic lake; and the use of peat mounds for treatment of household waste water

  18. Impact of emission control on regional air quality in the Pearl Delta River region, southern China

    Science.gov (United States)

    Wang, N.; Xuejiao, D.

    2017-12-01

    The Pearl River Delta (PRD) in China has been suffering from air quality issues and the government has implemented a series of strategies in controlling emissions. In an attempt to provide scientific support for improving air quality, the paper investigates the concerning past-to-present air quality data and assesses air quality resulting from emission control. Statistical data revealed that energy consumption doubled from 2004 to 20014 and vehicle usage increased significantly from 2006 to 2014. Due to the effect of control efforts, primary emission of SO2, NOx and PM2.5 decreased resulting in ambient concentrations of SO2, NO2 and PM10 decreased by 66%, 20% and 24%, respectively. However, O3 increased 19% because of the increase of VOC emission. A chemical transport model, the Community Multi-scale Air Quality, was employed to evaluate the responses of nitrate, ammonium, SOA, PM2.5 and O3 to changes in NOx, VOC and NH3 emissions. Three scenarios, a baseline scenario, a CAP scenario (control strength followed as past tendency), and a REF scenario (strict control referred to latest policy and plans), were conducted to investigate the responses and mechanisms. NOx controlling scenarios showed that NOx, nitrate and PM2.5 reduced by 1.8%, 0.7% and 0.2% under CAP and reduced by 7.2%, 1.8% and 0.3% under REF, respectively. The results indicated that reducing NOx emission caused the increase of atmospheric oxidizability, which might result in a compensation of PM2.5 due to the increase of nitrate or sulfate. NH3 controlling scenarios showed that nitrate was sensitive to NH3 emission in PRD, with nitrate decreased by 0 - 10.6% and 0 - 48% under CAP and REF, respectively. Since controlling NH3 emissions not only reduced ammonium but also significantly reduced nitrate, the implement of NH3 controlling strategy was highly suggested. The VOC scenarios revealed that though SOA was not the major component of PM2.5, controlling VOC emission might take effect in southwestern PRD

  19. Reconnaissance for radioactive deposits in Alaska, 1953

    Science.gov (United States)

    Matzko, John J.; Bates, Robert G.

    1955-01-01

    During the summer of 1953 the areas investigated for radioactive deposits in Alaska were on Nikolai Creek near Tyonek and on Likes Creek near Seward in south-central Alaska where carnotite-type minerals had been reported; in the headwaters of the Peace River in the eastern part of the Seward Peninsula and at Gold Bench on the South Fork of the Koyukuk River in east-central Alaska, where uranothorianite occurs in places associated with base metal sulfides and hematite; in the vicinity of Port Malmesbury in southeastern Alaska to check a reported occurrence of pitchblende; and, in the Miller House-Circle Hot Springs area of east-central Alaska where geochemical studies were made. No significant lode deposits of radioactive materials were found. However, the placer uranothorianite in the headwaters of the Peace River yet remains as an important lead to bedrock radioactive source materials in Alaska. Tundra cover prevents satisfactory radiometric reconnaissance of the area, and methods of geochemical prospecting such as soil and vegetation sampling may ultimately prove more fruitful in the search for the uranothorianite-sulfide lode source than geophysical methods.

  20. Urbanization signatures in strong versus weak precipitation over the Pearl River Delta metropolitan regions of China

    International Nuclear Information System (INIS)

    Li Weibiao; Chen Sheng; Wen Zhiping; Wang Baomin; Chen Guixing; Sha Weimin; Luo Cong; Feng Yerong

    2011-01-01

    We assess the issues of urban effects on the precipitation over the Pearl River Delta (PRD) metropolitan regions of China. The spatial and temporal variations of strong versus weak precipitation over the PRD and surrounding nonurban areas are investigated. The results show that the urbanization signatures in strong precipitation are significantly different from those in weak precipitation over the urban areas. The PRD experiences more strong precipitation but less weak precipitation compared to surrounding nonurban regions. In addition, the strong precipitation over the PRD displays a pronounced seasonal variation. The seasonality of weak precipitation, however, is much weaker over the PRD compared to the surrounding nonurban regions. Moreover, a strengthening in the precipitation intensity, a reduction in the rainfall frequency and an increase in the convective precipitation as well as the afternoon precipitation are found over the urban areas, which are probably associated with the abundance in strong precipitation and the deficit in weak precipitation over the PRD.

  1. Alligator Rivers Region Research Institute: annual research summary 1989-1990

    International Nuclear Information System (INIS)

    1991-01-01

    The Alligator Rivers Region Research Institute (ARRRI) research activities are associated with an assessment of environmental effect of mining in the region. While emphasis on baseline research is now much reduced, some projects are still necessary because of significant changes in the Magela Creek system, because new areas of proposed mining have been identified (e.g. Coronation Hill) and because the emphasis now being placed on rehabilitation research requires a sound knowledge of the Region's flora. The ARRRI rehabilitation research program has concentrated on the Ranger mine site, principally because it is at a critical planning stage where detailed research information is required. With regard to the development of techniques, research at the Institute has led to the development of specific analytical methods or protocols that can be used in assessing environmental impact. 39 tabs., 42 figs

  2. Problems of communicating radiation doses to aboriginal members of the public in the Alligator Rivers Region

    International Nuclear Information System (INIS)

    McLaughlin, D.

    1985-01-01

    Since the early 1970s, Aboriginal people of the Alligator Rivers Region have had to come to grips with the effects of uranium mining at Nabarlek and Ranger. One element in their cost-benefit approach to mine operations has been the expectation that bush foods in the region will not be contaminated by the mining operations. Recent studies on radionuclide concentrations in freshwater mussels (Velesunio angasi) in the region have shown this species, and perhaps others, to be efficient accumulators of radium. Information concerning natural radium accumulation in mussels and accompanying health risk estimates have been conveyed to Aboriginal people of the area and such information transfer has not been without its problems. Application of the ALARA principle to environmental management of the effluent pathways needs to consider Aboriginal expectations

  3. Recognition of key regions for restoration of phytoplankton communities in the Huai River basin, China

    Science.gov (United States)

    Zhao, Changsen; Liu, Changming; Xia, Jun; Zhang, Yongyong; Yu, Qiang; Eamus, Derek

    2012-02-01

    SummaryHealthy phytoplankton communities are the basis of healthy water ecosystems, and form the foundation of many freshwater food webs. Globally many freshwater ecosystems are degraded because of intensive human activities, so water ecosystem restoration is a burning issue worldwide. Selection of key regions for phytoplankton-related restoration is crucial for an effective aquatic eco-restoration. This paper presents a practical method for identification of key regions for phytoplankton-related restoration, using random forests (RFs) method to cluster sites based on dominance, biodiversity, water chemistry and ecological niche. We sampled phytoplankton for species richness and relative abundance and water quality in the Huai River basin (HRB), China to determine the phytoplankton communities' composition and structure and characterize of their ecological niches. A wider mean niche breadth of a species usually leads to a greater overlap with the niche of other species. Using these data and water quality indices, we identified the key regions for phytoplankton-related river restoration activities. Results indicate that our method for recognition of key regions is effective and practical and its application to the HRB identified the Northern Plain area as the key region for restoration. This area is severely polluted and contributes significantly to the HRB phytoplankton communities. Phytoplankton in this region is highly adaptable to environmental change and therefore will be relatively unharmed by environmental instability induced by restoration measures. During restoration, indices of water temperature, total phosphorus and chemical oxygen demand can be altered with little negative influence on phytoplankton communities, but measures that increase ammonia-nitrogen concentration would be highly detrimental. These results will provide valuable information for policy makers and stakeholders in water ecosystem restoration and sustainable basin management in the HRB.

  4. Regional contribution to PM1 pollution during winter haze in Yangtze River Delta, China.

    Science.gov (United States)

    Tang, Lili; Yu, Hongxia; Ding, Aijun; Zhang, Yunjiang; Qin, Wei; Wang, Zhuang; Chen, Wentai; Hua, Yan; Yang, Xiaoxiao

    2016-01-15

    To quantify regional sources contributing to submicron particulate matter (PM1) pollution in haze episodes, on-line measurements combining two modeling methods, namely, positive matrix factorization (PMF) and backward Lagrangian particle dispersion modeling (LPDM), were conducted for the period of one month in urban Nanjing, a city located in the western part of Yangtze River Delta (YRD) region of China. Several multi-day haze episodes were observed in December 2013. Long-range transport of biomass burning from the southwestern YRD region largely contributed to PM1 pollution with more than 25% of total organics mass in a lasting heavy haze. The LPDM analysis indicates that regional transport is a main source contributing to secondary low-volatility production. The high-potential source regions of secondary low-volatility production are mainly located in areas to the northeast of the city. High aerosol pollution was mainly contributed by regional transport associated with northeastern air masses. Such regional transport on average accounts for 46% of total NR-PM1 with sulfate and aged low-volatility organics being the largest fractions (>65%). Copyright © 2015 Elsevier B.V. All rights reserved.

  5. CLASSIFICATION OF BENTHIC BIOCENOSES OF THE LOWLAND RIVER TUDOVKA (TVER REGION, RUSSIA USING COMMUNITY FEATURES

    Directory of Open Access Journals (Sweden)

    M. Schletterer

    2017-01-01

    Full Text Available Within the joint Russian-Austrian monitoring programme “REFCOND_VOLGA (2006 – 20XX”, monitoring sites were established in the headwaters of the Volga (Tver Region. River Tudovka, a right tributary to the Volga River, was included within this monitoring programme as its catchment is partly protected and has only few anthropogenic activities. The monitoring activities include physico-chemical and hydraulic parameters as well as biota with a focus is on benthic organisms (diatoms and macrozoobenthos. In this work, the longitudinal patterns in community structure are classified in the lowland river Tudovka using a novel feature-based approach taken from signal processing theory. The method first clusters field sampling data into longitudinal classes (upper, middle, lower course. Community features based on the relative frequency of individual species occurring per class are then generated. We apply both generative and discriminative classification methods. The application of generative methods provides data models which predict the probability of a new sample to belong to an existing class. In contrast, discriminative approaches search for differences between classes and allocate new data accordingly. Leveraging both methods allows for the creation of stable classifications. On this basis we show how the community features can be used to predict the longitudinal class. The community features approach also allows for a robust cross-comparison of investigation reaches over time. In cases where suitable long-term data set are available, predictive models using this approach can also be developed.

  6. Regional variation in the intensity of humpback whale predation on Pacific herring in the Gulf of Alaska

    Science.gov (United States)

    Moran, J. R.; Heintz, R. A.; Straley, J. M.; Vollenweider, J. J.

    2018-01-01

    We modeled the biomass of Pacific herring (Clupea pallasii) consumed by humpback whales (Megaptera novaeangliae) to determine if whales are preventing the recovery of some herring populations in the Gulf of Alaska. We estimated consumption, by whales, of two depressed (Lynn Canal, Prince William Sound) and one robust (Sitka Sound) herring populations during fall/winter of 2007-2008 and 2008-2009. Consumption estimates relied on observations of whale abundance, prey selection, and herring energy content along with published data on whale size and metabolic rate. Herring biomass removed by whales was compared with independent estimates of herring abundance to assess the impact of predation on each population. Whales removed a greater proportion of the total biomass of herring available in Lynn Canal and Prince William Sound than in Sitka Sound. Biomass removals were greatest in Prince William Sound where we observed the largest number of whales foraging on herring. The biomass of herring consumed in Prince William Sound approximated the biomass lost to natural mortality over winter as projected by age-structured stock assessments. Though whales also focused their foraging on herring during the fall in Lynn Canal, whales were less abundant resulting in lower estimated consumption rates. Whales were more abundant in Sitka Sound than in Lynn Canal but foraged predominately on euphausiids. Herring abundance was greater in Sitka Sound, further reducing the overall impact on the herring population. These data indicate that the focused predation in Prince William Sound can exert top-down controlling pressure, but whale populations are not a ubiquitous constraint on forage fish productivity in the Gulf of Alaska at this time.

  7. Regional precipitation trend analysis at the Langat River Basin, Selangor, Malaysia

    Science.gov (United States)

    Palizdan, Narges; Falamarzi, Yashar; Huang, Yuk Feng; Lee, Teang Shui; Ghazali, Abdul Halim

    2014-08-01

    Various hydrological and meteorological variables such as rainfall and temperature have been affected by global climate change. Any change in the pattern of precipitation can have a significant impact on the availability of water resources, agriculture, and the ecosystem. Therefore, knowledge on rainfall trend is an important aspect of water resources management. In this study, the regional annual and seasonal precipitation trends at the Langat River Basin, Malaysia, for the period of 1982-2011 were examined at the 95 % level of significance using the regional average Mann-Kendall (RAMK) test and the regional average Mann-Kendall coupled with bootstrap (RAMK-bootstrap) method. In order to identify the homogeneous regions respectively for the annual and seasonal scales, firstly, at-site mean total annual and separately at-site mean total seasonal precipitation were spatialized into 5 km × 5 km grids using the inverse distance weighting (IDW) algorithm. Next, the optimum number of homogeneous regions (clusters) is computed using the silhouette coefficient approach. Next, the homogeneous regions were formed using the K-mean clustering method. From the annual scale perspective, all three regions showed positive trends. However, the application of two methods at this scale showed a significant trend only in the region AC1. The region AC2 experienced a significant positive trend using only the RAMK test. On a seasonal scale, all regions showed insignificant trends, except the regions I1C1 and I1C2 in the Inter-Monsoon 1 (INT1) season which experienced significant upward trends. In addition, it was proven that the significance of trends has been affected by the existence of serial and spatial correlations.

  8. Paleocene origin of the cockroach families Blaberidae and Corydiidae: Evidence from Amur River region of Russia.

    Science.gov (United States)

    Vršanský, Peter; Vidlička, L'Ubomír; Barna, Peter; Bugdaeva, Eugenia; Markevich, Valentina

    2013-01-01

    Morphna paleo sp. n., the earliest winged representative of any living cockroach genus and the earliest representative of the family Blaberidae, is described from the Danian Arkhara-Boguchan coal mine in the Amur River region (Russian Far East). The branched Sc and A suggest Ectobiidae (=Blattellidae) probably is not the ancestral family because Blaberidae were derived directly from the extinct family Mesoblattindae. The associated Danian locality Belaya Gora yielded Ergaula stonebut sp. n., the earliest record of the family Corydiidae. Both species belong to genera codominant in the Messel locality, thus validating their dominance in early Cenozoic assemblages.

  9. A regional neural network model for predicting mean daily river water temperature

    Science.gov (United States)

    Wagner, Tyler; DeWeber, Jefferson Tyrell

    2014-01-01

    Water temperature is a fundamental property of river habitat and often a key aspect of river resource management, but measurements to characterize thermal regimes are not available for most streams and rivers. As such, we developed an artificial neural network (ANN) ensemble model to predict mean daily water temperature in 197,402 individual stream reaches during the warm season (May–October) throughout the native range of brook trout Salvelinus fontinalis in the eastern U.S. We compared four models with different groups of predictors to determine how well water temperature could be predicted by climatic, landform, and land cover attributes, and used the median prediction from an ensemble of 100 ANNs as our final prediction for each model. The final model included air temperature, landform attributes and forested land cover and predicted mean daily water temperatures with moderate accuracy as determined by root mean squared error (RMSE) at 886 training sites with data from 1980 to 2009 (RMSE = 1.91 °C). Based on validation at 96 sites (RMSE = 1.82) and separately for data from 2010 (RMSE = 1.93), a year with relatively warmer conditions, the model was able to generalize to new stream reaches and years. The most important predictors were mean daily air temperature, prior 7 day mean air temperature, and network catchment area according to sensitivity analyses. Forest land cover at both riparian and catchment extents had relatively weak but clear negative effects. Predicted daily water temperature averaged for the month of July matched expected spatial trends with cooler temperatures in headwaters and at higher elevations and latitudes. Our ANN ensemble is unique in predicting daily temperatures throughout a large region, while other regional efforts have predicted at relatively coarse time steps. The model may prove a useful tool for predicting water temperatures in sampled and unsampled rivers under current conditions and future projections of climate

  10. MACROZOOBENTHOS OF MOUNTAIN RIVERS OF THE TRANSCARPATHIAN REGION AS A FORAGE BASE OF BENTHOPHAGOUS FISHES AND SAPROBITY INDICATOR

    Directory of Open Access Journals (Sweden)

    S. Kruzhylina

    2014-12-01

    Full Text Available Purpose. To study qualitative and qualitative indices of macrozoobenthos as one of main components of the forage base of benthophagous fishes in mountain river reaches of the Transcarpathian region and determination of their saprobity level. Methodology. Thhj,9.e study was carried out in summer period of 2009 in mountain river reaches of the Tisa river catchment. Zoobenthos samples were collected by a Surber sampler (25 × 25 cm on the bottoms of different fractions with different water flow rate (riffle, run, pool. Collection, processing and interpretation of the obtained data was carried out according to generally accepted hydrobiological methods developed for mountain river studies. Saprobity was of the studied rivers was calculated by Pantle-Buck formula. The Zelinka-Marvan saprobity index was used for calculations. Findings. Qualitative and quantitative macrozoobenthos indices have been studied. The number of zoobenthos on the investigated river sections ranged from 416 to 7712 ind./m2 with biomasses from 2.96 to 83.84 g/m2. The major portion of the zoobenthic biomass in the majority of rivers was due to caddis fly larvae composing up to 93% of the total biomass. An important role in the total biomass of the zoobenthos also belonged to mayfly (up to 53% and stonefly (up to 55% larvae and in lower degree amphipods (up to 39%, chironomid larvae (up to 14% and aquatic coleopterans (up to 5%. According to the calculated potential fish productivity, the mountain rivers can be apparently separated into three groups: little productive (4.2–12.7 kg/ha, medium productive (13.2–21.6 kg/ha and high productive (25.3–85.3 kg/ha. Mountain river reaches of the Transcarpathian region were found to belong to pure χ-saprobic, and о- і β-mesosaprobic zones, the saprobity index in which ranged from 0.35 (Rika river to 1.7 (Shipot river. Originality. For further calculation and assessment of brown trout (Salmo trutta and European grayling (Thymallus

  11. Groundwater recharge, circulation and geochemical evolution in the source region of the Blue Nile River, Ethiopia

    International Nuclear Information System (INIS)

    Kebede, Seifu; Travi, Yves; Alemayehu, Tamiru; Ayenew, Tenalem

    2005-01-01

    Geochemical and environmental isotope data were used to gain the first regional picture of groundwater recharge, circulation and its hydrochemical evolution in the upper Blue Nile River basin of Ethiopia. Q-mode statistical cluster analysis (HCA) was used to classify water into objective groups and to conduct inverse geochemical modeling among the groups. Two major structurally deformed regions with distinct groundwater circulation and evolution history were identified. These are the Lake Tana Graben (LTG) and the Yerer Tullu Wellel Volcanic Lineament Zone (YTVL). Silicate hydrolysis accompanied by CO 2 influx from deeper sources plays a major role in groundwater chemical evolution of the high TDS Na-HCO 3 type thermal groundwaters of these two regions. In the basaltic plateau outside these two zones, groundwater recharge takes place rapidly through fractured basalts, groundwater flow paths are short and they are characterized by low TDS and are Ca-Mg-HCO 3 type waters. Despite the high altitude (mean altitude ∼2500 masl) and the relatively low mean annual air temperature (18 deg. C) of the region compared to Sahelian Africa, there is no commensurate depletion in δ 18 O compositions of groundwaters of the Ethiopian Plateau. Generally the highland areas north and east of the basin are characterized by relatively depleted δ 18 O groundwaters. Altitudinal depletion of δ 18 O is 0.1%o/100 m. The meteoric waters of the Blue Nile River basin have higher d-excess compared to the meteoric waters of the Ethiopian Rift and that of its White Nile sister basin which emerges from the equatorial lakes region. The geochemically evolved groundwaters of the YTVL and LTG are relatively isotopically depleted when compared to the present day meteoric waters reflecting recharge under colder climate and their high altitude

  12. Groundwater recharge, circulation and geochemical evolution in the source region of the Blue Nile River, Ethiopia

    Energy Technology Data Exchange (ETDEWEB)

    Kebede, Seifu [Laboratory of Hydrogeology, University of Avignon, 33 Rue Louis Pasteur, 84000 Avignon (France) and Department of Geology and Geophysics, Addis Ababa University, P.O. Box 1176, Addis Ababa (Ethiopia)]. E-mail: seifu.kebede@univ-avignon.fr; Travi, Yves [Laboratory of Hydrogeology, University of Avignon, 33 Rue Louis Pasteur, 84000 Avignon (France); Alemayehu, Tamiru [Department of Geology and Geophysics, Addis Ababa University, P.O. Box 1176, Addis Ababa (Ethiopia); Ayenew, Tenalem [Department of Geology and Geophysics, Addis Ababa University, P.O. Box 1176, Addis Ababa (Ethiopia)

    2005-09-15

    Geochemical and environmental isotope data were used to gain the first regional picture of groundwater recharge, circulation and its hydrochemical evolution in the upper Blue Nile River basin of Ethiopia. Q-mode statistical cluster analysis (HCA) was used to classify water into objective groups and to conduct inverse geochemical modeling among the groups. Two major structurally deformed regions with distinct groundwater circulation and evolution history were identified. These are the Lake Tana Graben (LTG) and the Yerer Tullu Wellel Volcanic Lineament Zone (YTVL). Silicate hydrolysis accompanied by CO{sub 2} influx from deeper sources plays a major role in groundwater chemical evolution of the high TDS Na-HCO {sub 3} type thermal groundwaters of these two regions. In the basaltic plateau outside these two zones, groundwater recharge takes place rapidly through fractured basalts, groundwater flow paths are short and they are characterized by low TDS and are Ca-Mg-HCO {sub 3} type waters. Despite the high altitude (mean altitude {approx}2500 masl) and the relatively low mean annual air temperature (18 deg. C) of the region compared to Sahelian Africa, there is no commensurate depletion in {delta} {sup 18}O compositions of groundwaters of the Ethiopian Plateau. Generally the highland areas north and east of the basin are characterized by relatively depleted {delta} {sup 18}O groundwaters. Altitudinal depletion of {delta} {sup 18}O is 0.1%o/100 m. The meteoric waters of the Blue Nile River basin have higher d-excess compared to the meteoric waters of the Ethiopian Rift and that of its White Nile sister basin which emerges from the equatorial lakes region. The geochemically evolved groundwaters of the YTVL and LTG are relatively isotopically depleted when compared to the present day meteoric waters reflecting recharge under colder climate and their high altitude.

  13. Time-Series Analysis of Remotely-Sensed SeaWiFS Chlorophyll in River-Influenced Coastal Regions

    Science.gov (United States)

    Acker, James G.; McMahon, Erin; Shen, Suhung; Hearty, Thomas; Casey, Nancy

    2009-01-01

    The availability of a nearly-continuous record of remotely-sensed chlorophyll a data (chl a) from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) mission, now longer than ten years, enables examination of time-series trends for multiple global locations. Innovative data analysis technology available on the World Wide Web facilitates such analyses. In coastal regions influenced by river outflows, chl a is not always indicative of actual trends in phytoplankton chlorophyll due to the interference of colored dissolved organic matter and suspended sediments; significant chl a timeseries trends for coastal regions influenced by river outflows may nonetheless be indicative of important alterations of the hydrologic and coastal environment. Chl a time-series analysis of nine marine regions influenced by river outflows demonstrates the simplicity and usefulness of this technique. The analyses indicate that coastal time-series are significantly influenced by unusual flood events. Major river systems in regions with relatively low human impact did not exhibit significant trends. Most river systems with demonstrated human impact exhibited significant negative trends, with the noteworthy exception of the Pearl River in China, which has a positive trend.

  14. Economic growth and change in southeast Alaska.

    Science.gov (United States)

    Rhonda Mazza

    2004-01-01

    This report focuses on economic trends since the 1970s in rural southeast Alaska. These trends are compared with those in the Nation and in nonmetropolitan areas of the country to determine the extent to which the economy in rural southeast Alaska is affected by regional activity and by larger market forces. Many of the economic changes occurring in rural southeast...

  15. The State of Alaska Agency Directory

    Science.gov (United States)

    Administrative Services Division of Banking and Securities Division of Community & Regional Affairs Division Services Public Notices Alaska Communities Resident Working Finding Work in Alaska Private Industry Jobs Development Environmental Conservation Fish and Game Governor's Office Health and Social Services Labor and

  16. Western Alaska ESI: SOCECON (Socioeconomic Resource Points and Lines)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains human-use resource data for airports, mining sites, area boundaries, and scenic rivers in Western Alaska. Vector points and lines in this data...

  17. State of Alaska

    Science.gov (United States)

    Assistance Center Occupations Requiring Licenses Corporations Employer Information Alaska's Job Bank/Alaska Assistance Center Alaska's Job Bank Occupations Requiring Licenses Corporations Unemployment Insurance Tax Child Care Child Protection Denali KidCare Food Stamps Poison Control Seasonal Flu Immunization

  18. Detection of petroleum contamination in river sediments from Quebec City region using GC-IRMS

    International Nuclear Information System (INIS)

    Rogers, K.M.; Savard, M.M.

    1999-01-01

    Isotopic analysis by compound specific gas chromatography-isotope ratio mass spectrometry (GC-IRMS) is used to detect and characterize petroleum pollution in surficial sediments along the St Lawrence River, near Quebec City. Unusually mature n-alkane distributions have been found in some recent intertidal sediments in the region. GC-IRMS results suggest that the n-alkanes are not derived from indigenous organic sources because they carry delta 13 C values between -30.0 and -27.0 per mille, as well as very small isotopic differences between odd and even numbered n-alkanes, which are both typically associated with petroleum products. Comparison of these sediments with bunker fuel, an oil used in the shipping industry, has shown a close isotopic correlation in some sites, which is further supported by biomarkers. Overall, the contamination has been dispersed along the river but is generally localized around the industrial region where hydrocarbon transfer from shore storage to ships takes place. This study illustrates how GC-IRMS can be used effectively in the detection and characterization of petroleum pollutants in sediments. (author)

  19. Measurement and Prediction of Regional Tourism Sustainability: An Analysis of the Yangtze River Economic Zone, China

    Directory of Open Access Journals (Sweden)

    Canmian Liu

    2018-04-01

    Full Text Available In view of sustainable development of tourism, this paper firstly constructs a more comprehensive and scientific index system from the economical/societal/resource-related/environmental aspects of tourism and evaluates the sustainable and comprehensive development level of tourism in 11 provinces and cities of the Yangtze River economic zone by using the weighted TOPSIS (The Technique for Order Preference by Similarity to an Ideal Solution method; secondly, it analyzes the coupling coordination evolution relationship between tourism and the economy/society/resources/environment in different provinces and cities of the Yangtze river economic zone based on the coupling coordination model from the spatio-temporal dimension; and finally, it predicts the coupling coordination degree of the provinces and cities in the region in the next few years by the grey model (1,1 and puts forward some countermeasures and suggestions. According to the study, this method provides an effective reference to the study on the sustainable development of tourism and is very significant for learning the sustainable development of regional tourism and establishing specific and scientific countermeasures for improvement.

  20. Managing the three-rivers headwater region, china: from ecological engineering to social engineering.

    Science.gov (United States)

    Fang, Yiping

    2013-09-01

    The three-rivers headwater region (THRHR) of Qinghai province, China plays a key role as source of fresh water and ecosystem services for central and eastern China. Global warming and human activities in the THRHR have threatened the ecosystem since the 1980s. Therefore, the Chinese government has included managing of the THRHR in the national strategy since 2003. The State Integrated Test and Demonstration Region of the THRHR highlights the connection with social engineering (focus on improving people's livelihood and well-being) in managing nature reserves. Based on this program, this perspective attempts a holistic analysis of the strategic role of the THRHR, requirements for change, indices of change, and approaches to change. Long-term success of managing nature reserves requires effective combination of ecological conservation, economic development, and social progress. Thus, the philosophy of social engineering should be employed as a strategy to manage the THRHR.

  1. Visualizing ecological sensitivity assessment of Huangnan, in the Three-river Region, China, based on GIS

    Science.gov (United States)

    Meng, Xia; Guo, Luo

    2017-07-01

    Huangnan Tibetan Autonomous Prefecture is located in the three-river source region (the TRSR) in the Qinghai-Tibetan Plateau, China, which is characterized with ecological sensitivity and vulnerability. In the paper, we integrated remote sensing images, field investigation and social-economic data , and with the help of analytic hierarchy process (AHP) and comprehensive index methods, a sensitivity assessment system was built to calculate ecological sensitivity scores and assign levels for the study area. Results show that: areas which are moderately or even highly ecologically sensitive account for 54.02%, distributed in south, north and northeast of study area and those that have most apparent ecological sensitivity are mainly located in Zeekog, northwest of Huangnan while other counties enjoy relatively lower sensitivity. The results will facilitate future region management and planning for decision-makers.

  2. Diets and abundances of aquatic and semi-aquatic reptiles in the Alligator Rivers Region

    International Nuclear Information System (INIS)

    Shine, R.

    1986-01-01

    The mining and milling of uranium in the Alligator River Region in the Northern Territory has raised the possibility that heavy metals and radionuclides might escape into the aquatic system and be accumulated by the reptilian fauna. Aquatic and semi-aquatic reptiles are regularly eaten by Aboriginal people of the region, and data on diets and reproduction of these species, as well as on their dispersion and abundance, are essential before the possibility that reptiles might act as pathways for these contaminants to Aboriginals can be assessed. The objectives of this study were to provide quantitative data on the diets of filesnakes, sand goannas and water goannas, to provide information on seasonal changes in their abundance and distribution within the Magela Creek system; and to describe their reproductive cycles

  3. Emission inventory of anthropogenic air pollutants and VOC species in the Yangtze River Delta region, China

    Directory of Open Access Journals (Sweden)

    C. Huang

    2011-05-01

    Full Text Available The purpose of this study is to develop an emission inventory for major anthropogenic air pollutants and VOC species in the Yangtze River Delta (YRD region for the year 2007. A "bottom-up" methodology was adopted to compile the inventory based on major emission sources in the sixteen cities of this region. Results show that the emissions of SO2, NOx, CO, PM10, PM2.5, VOCs, and NH3 in the YRD region for the year 2007 are 2392 kt, 2293 kt, 6697 kt, 3116 kt, 1511 kt, 2767 kt, and 459 kt, respectively. Ethylene, mp-xylene, o-xylene, toluene, 1,2,4-trimethylbenzene, 2,4-dimethylpentane, ethyl benzene, propylene, 1-pentene, and isoprene are the key species contributing 77 % to the total ozone formation potential (OFP. The spatial distribution of the emissions shows the emissions and OFPs are mainly concentrated in the urban and industrial areas along the Yangtze River and around Hangzhou Bay. The industrial sources, including power plants other fuel combustion facilities, and non-combustion processes contribute about 97 %, 86 %, 89 %, 91 %, and 69 % of the total SO2, NOx, PM10, PM2.5, and VOC emissions. Vehicles take up 12.3 % and 12.4 % of the NOx and VOC emissions, respectively. Regarding OFPs, the chemical industry, domestic use of paint & printing, and gasoline vehicles contribute 38 %, 24 %, and 12 % to the ozone formation in the YRD region.

  4. A simple method to predict regional fish abundance: an example in the McKenzie River Basin, Oregon

    Science.gov (United States)

    D.J. McGarvey; J.M. Johnston

    2011-01-01

    Regional assessments of fisheries resources are increasingly called for, but tools with which to perform them are limited. We present a simple method that can be used to estimate regional carrying capacity and apply it to the McKenzie River Basin, Oregon. First, we use a macroecological model to predict trout densities within small, medium, and large streams in the...

  5. Tectono-Thermal History Modeling and Reservoir Simulation Study of the Nenana Basin, Central Alaska: Implications for Regional Tectonics and Geologic Carbon Sequestration

    Science.gov (United States)

    Dixit, Nilesh C.

    Central Interior Alaska is an active tectonic deformation zone highlighted by the complex interactions of active strike-slip fault systems with thrust faults and folds of the Alaska Range fold-and-thrust belt. This region includes the Nenana basin and the adjacent Tanana basin, both of which have significant Tertiary coal-bearing formations and are also promising areas (particularly the Nenana basin) with respect to hydrocarbon exploration and geologic carbon sequestration. I investigate the modern-day crustal architecture of the Nenana and Tanana basins using seismic reflection, aeromagnetic and gravity anomaly data and demonstrate that the basement of both basins shows strong crustal heterogeneity. The Nenana basin is a deep (up to 8 km), narrow transtensional pull-apart basin that is deforming along the left-lateral Minto Flats fault zone. The Tanana basin has a fundamentally different geometry and is a relatively shallow (up to 2 km) asymmetrical foreland basin with its southern, deeper side controlled by the northern foothills of the central Alaska Range. NE-trending strike-slip faults within the Tanana basin are interpreted as a zone of clockwise crustal block rotation. Seismic refection data, well data, fracture data and apatite fission track data further constrain the tectonic evolution and thermal history of the Nenana basin. The Nenana basin experienced four distinct tectonic phases since Late Paleocene time. The basin initiated as a narrow half-graben structure in Late Paleocene with accumulation of greater than 6000 feet of sediments. The basin was then uplifted, resulting in the removal of up to 5000 feet of Late Paleocene sediments in Eocene to Oligocene time. During Middle to Late Miocene time, left lateral strike-slip faulting was superimposed on the existing half-graben system. Transtensional deformation of the basin began in the Pliocene. At present, Miocene and older strata are exposed to temperatures > 60°C in the deeper parts of the Nenana

  6. The influence of local oil exploration and regional wildfires on summer 2015 aerosol over the North Slope of Alaska

    Directory of Open Access Journals (Sweden)

    J. M. Creamean

    2018-01-01

    Full Text Available The Arctic is warming at an alarming rate, yet the processes that contribute to the enhanced warming are not well understood. Arctic aerosols have been targeted in studies for decades due to their consequential impacts on the energy budget, both directly and indirectly through their ability to modulate cloud microphysics. Even with the breadth of knowledge afforded from these previous studies, aerosols and their effects remain poorly quantified, especially in the rapidly changing Arctic. Additionally, many previous studies involved use of ground-based measurements, and due to the frequent stratified nature of the Arctic atmosphere, brings into question the representativeness of these datasets aloft. Here, we report on airborne observations from the US Department of Energy Atmospheric Radiation Measurement (ARM program's Fifth Airborne Carbon Measurements (ACME-V field campaign along the North Slope of Alaska during the summer of 2015. Contrary to previous evidence that the Alaskan Arctic summertime air is relatively pristine, we show how local oil extraction activities, 2015's central Alaskan wildfires, and, to a lesser extent, long-range transport introduce aerosols and trace gases higher in concentration than previously reported in Arctic haze measurements to the North Slope. Although these sources were either episodic or localized, they serve as abundant aerosol sources that have the potential to impact a larger spatial scale after emission.

  7. Origin of last-glacial loess in the western Yukon-Tanana Upland, central Alaska, USA

    Science.gov (United States)

    Muhs, Daniel; Pigati, Jeffrey S.; Budahn, James R.; Skipp, Gary L.; Bettis, E. Arthur; Jensen, Britta

    2018-01-01

    Loess is widespread over Alaska, and its accumulation has traditionally been associated with glacial periods. Surprisingly, loess deposits securely dated to the last glacial period are rare in Alaska, and paleowind reconstructions for this time period are limited to inferences from dune orientations. We report a rare occurrence of loess deposits dating to the last glacial period, ~19 ka to ~12 ka, in the Yukon-Tanana Upland. Loess in this area is very coarse grained (abundant coarse silt), with decreases in particle size moving south of the Yukon River, implying that the drainage basin of this river was the main source. Geochemical data show, however, that the Tanana River valley to the south is also a likely distal source. The occurrence of last-glacial loess with sources to both the south and north is explained by both regional, synoptic-scale winds from the northeast and opposing katabatic winds that could have developed from expanded glaciers in both the Brooks Range to the north and the Alaska Range to the south. Based on a comparison with recent climate modeling for the last glacial period, seasonality of dust transport may also have played a role in bringing about contributions from both northern and southern sources.

  8. Hydrochemistry of the Parauari-Maues Acu river basin (Amazon region, Brazil)

    International Nuclear Information System (INIS)

    Bringel, S.R.B.

    1980-08-01

    The chemical composition of the Parauari-Maues Acu basin is studied through the determination of pH, calcium, magnesium, iron, chloride, sodium, potassium, zinc, copper and manganese. Four expeditions were made and samples were collected in 16 different points of the main course. Chemical analysis of the rivers waters shows seasonal flutuations of the concentrations of the elements in the main river as well as in the main afluents like Nambi river, Amana river and Urupadi river. (Author) [pt

  9. Climatic variability of river outflow in the Pantanal region and the influence of sea surface temperature

    Science.gov (United States)

    Silva, Carlos Batista; Silva, Maria Elisa Siqueira; Ambrizzi, Tércio

    2017-07-01

    This paper investigates possible linear relationships between climate, hydrology, and oceanic surface variability in the Pantanal region (in South America's central area), over interannual and interdecadal time ranges. In order to verify the mentioned relations, lagged correlation analysis and linear adjustment between river discharge at the Pantanal region and sea surface temperature were used. Composite analysis for atmospheric fields, air humidity flux divergence, and atmospheric circulation at low and high levels, for the period between 1970 and 2003, was analyzed. Results suggest that the river discharge in the Pantanal region is linearly associated with interdecadal and interannual oscillations in the Pacific and Atlantic oceans, making them good predictors to continental hydrological variables. Considering oceanic areas, 51 % of the annual discharge in the Pantanal region can be linearly explained by mean sea surface temperature (SST) in the Subtropical North Pacific, Tropical North Pacific, Extratropical South Pacific, and Extratropical North Atlantic over the period. Considering a forecast approach in seasonal scale, 66 % of the monthly discharge variance in Pantanal, 3 months ahead of SST, is explained by the oceanic variables, providing accuracy around 65 %. Annual discharge values in the Pantanal region are strongly related to the Pacific Decadal Oscillation (PDO) variability (with 52 % of linear correlation), making it possible to consider an interdecadal variability and a consequent subdivision of the whole period in three parts: 1st (1970-1977), 2nd (1978-1996), and 3rd (1997-2003) subperiods. The three subperiods coincide with distinct PDO phases: negative, positive, and negative, respectively. Convergence of humidity flux at low levels and the circulation pattern at high levels help to explain the drier and wetter subperiods. During the wetter 2nd subperiod, the air humidity convergence at low levels is much more evident than during the other two

  10. Managing Environmental Flows for Impounded Rivers in Semi-Arid Regions- A Habitat Suitability Index (HSI) Approach for the Assessment of River Habitat for Salmonid Populations

    Science.gov (United States)

    Pai, H.; Sivakumaran, K.; Villamizar, S. R.; Flanagan, J.; Guo, Q.; Harmon, T. C.

    2013-12-01

    Balancing ecosystem health in water-scarce, agriculturally dominated river basins remains a challenge. In dry water years, maintaining conditions for restored and sustained indigenous fish populations (a frequently used indicator for ecosystem health) is particularly challenging. Competing human demands include urban and agricultural water supplies, hydropower, and flood control. In many semi-arid regions, increasing drought intensity and frequency under future climate scenarios will combine with population increases to water scarcity. The goal of this work is to better understand how reservoir releases affect fish habitat and overall river aquatic ecosystem quality. Models integrating a diverse array of physical and biological processes and system state are used to forecast the river ecosystem response to changing drivers. We propose a distributed parameter-based Habitat Suitability Index (HSI) approach for assessing fish habitat quality. Our river ecosystem HSI maps are based on a combination of the following: (1) In situ data describing stream flow and water quality conditions; (2) Spatial observations, including surveyed cross-sections, aerial imagery and digital elevation maps (DEM) of the river and its riparian corridor; and (3) Simulated spatially distributed water depths, flow velocities, and temperatures estimated from 1D and 2D river flow and temperature models (HEC-RAS and CE-QUAL-W2, respectively). With respect to (2), image processing schemes are used to classify and map key habitat features, namely riparian edge and shallow underwater vegetation. HSI maps can be modified temporally to address specific life cycle requirements of indicator fish species. Results are presented for several reaches associated with the San Joaquin River Restoration Project, focusing on several components of the Chinook salmon life cycle. HSI maps and interpretations are presented in the context of a range of prescribed reservoir release hydrographs linked to California water

  11. Simulation of river plume behaviors in a tropical region: Case study of the Upper Gulf of Thailand

    Science.gov (United States)

    Yu, Xiaojie; Guo, Xinyu; Morimoto, Akihiko; Buranapratheprat, Anukul

    2018-02-01

    River plumes are a general phenomenon in coastal regions. Most previous studies focus on river plumes in middle and high latitudes with few studies examining those in low latitude regions. Here, we apply a numerical model to the Upper Gulf of Thailand (UGoT) to examine a river plume in low latitudes. Consistent with observational data, the modeled plume has seasonal variation dependent on monsoon conditions. During southwesterly monsoons, the plume extends northeastward to the head of the gulf; during northeasterly monsoons, it extends southwestward to the mouth of the gulf. To examine the effects of latitude, wind and river discharge on the river plume, we designed several numerical experiments. Using a middle latitude for the UGoT, the bulge close to the river mouth becomes smaller, the downstream current flows closer to the coast, and the salinity in the northern UGoT becomes lower. The reduction in the size of the bulge is consistent with the relationship between the offshore distance of a bulge and the Coriolis parameter. Momentum balance of the coastal current is maintained by advection, the Coriolis force, pressure gradient and internal stresses in both low and middle latitudes, with the Coriolis force and pressure gradient enlarged in the middle latitude. The larger pressure gradient in the middle latitude is induced by more offshore freshwater flowing with the coastal current, which induces lower salinity. The influence of wind on the river plume not only has the advection effects of changing the surface current direction and increasing the surface current speed, but also decreases the current speed due to enhanced vertical mixing. Changes in river discharge influence stratification in the UGoT but have little effect on the behavior of the river plume.

  12. Regional hydrology of the Dolores River Basin, eastern Paradox Basin, Colorado and Utah

    International Nuclear Information System (INIS)

    Weir, J.E. Jr.; Maxfield, E.B.; Zimmerman, E.A.

    1983-01-01

    The Dolores River Basin, is in the eastern part of the Paradox Basin and includes the eastern slope of the La Sal Mountains, the western slopes of the Rico and La Plata Mountains, and the southwest flank of the Uncompahgre Plateau. The climate of this area is more humid than most of the surrounding Colorado Plateau region. Precipitation ranges from slightly 200 mm/yr to 1000 mm/yr; the estimated volume of water falling on the area is 4000 x 10 6 cm 3 /yr. Of this total, about 600 x 10 6 cm 3 /yr is runoff; 190 x 10 6 cm 3 /yr recharges the upper ground-water system; and an estimated 55 x 10 6 cm 3 returns to the atmosphere via evapotranspiration from stream valleys. The remainder evaporates. Principal hydrogeologic units are permeable sandstone and limestone and nearly impermeable salt (halitic) deposits. Structurally, the area is dominated by northwest-trending salt anticlines and contiguous faults paralleled by synclinal structures. The Uncompahgre Plateau lies along the north and northeast sides of the area. The instrusive masses that form the La Sal Mountains are laccoliths with bysmaliths and other complex intrusive forms comprising, in gross form, moderately faulted omal structures. Intrusive rocks underlie the La Plata and Rico Mountains along the southeastern edge of the area. These geologic structures significantly modify ground-water flow patterns in the upper ground-water system, but have no conspicuous effect on the flow regime in the lower ground-water system. The water in the upper ground-water system generally is fresh except where it is affected by evaporite dissolution from salt anticlines. The water of the lower ground-water system is slightly saline to briny. Water quality of the Dolores River is slightly saline to fresh, based on dissolved chemical constituents; some of the smaller tributaries of the river have saline water

  13. Regional dynamics of persistent organic pollutants (POPs) in the Pearl River Delta, China: Implications and perspectives

    International Nuclear Information System (INIS)

    Zhang Kai; Zhang Baozhong; Li Shaomeng; Zeng, Eddy Y.

    2011-01-01

    The mass transport budgets of 1,1,1-trichloro-2,2-bis(chlorophenyl)ethane (p,p'-DDT) and decabromodiphenyl ether (BDE-209) in the Pearl River Delta, South China were calculated based on previously collected data. Residual p,p'-DDT, mostly related to historical use, has largely settled into soil (780,000 kg), while the soil BDE-209 inventory (44,000 kg) is considerably smaller. Conversely, large amounts of BDE-209 currently used in numerous commercial products have resulted in a much higher atmospheric depositional flux of BDE-209 (28,100 kg/yr) relative to p,p'-DDT (310 kg/yr). The soil inventory of p,p'-DDT is predicted to decrease to half of its current value after 22 years, and the percent area containing soil p,p'-DDT at levels exceeding the effects range-medium (27 ng/g) will decrease from 40% to 20%. Finally, soil BDE-209 inventory will reach an equilibrium value of 940 tons in ∼60 years, when BDE-209 levels in 50% of soil will be above an equivalent risk guideline value (125 ng/g). - Highlights: → Transport budgets of p,p'-DDT and BDE-209 in the Pearl River Delta were built. → Dry aerial deposition is the dominant route to transport p,p'-DDT and BDE-209. → Soil inventory of p,p'-DDT is much larger than that of BDE-209. → Soil inventory of p,p'-DDT would decline to half of its current value in 22 years. → Soil BDE-209 inventory is expected to reach an equilibrium value in ∼60 years. - Regional dynamics of p,p'-DDT and BDE-209 in the Pearl River Delta (South China) are examined and used to predict temporal variances.

  14. Global surveys of reservoirs and lakes from satellites and regional application to the Syrdarya river basin

    International Nuclear Information System (INIS)

    Jean-François, Crétaux; Adalbert, Arsen; Muriel, Bergé-Nguyen; Sylvain, Biancamaria; Mélanie, Becker

    2015-01-01

    Large reservoirs along rivers regulate downstream flows to generate hydropower but may also store water for irrigation and urban sectors. Reservoir management therefore becomes critical, particularly for transboundary basins, where coordination between riparian countries is needed. Reservoir management is even more important in semiarid regions where downstream water users may be totally reliant on upstream reservoir releases. If the water resources are shared between upstream and downstream countries, potentially opposite interests arise as is the case in the Syrdarya river in Central Asia. In this case study, remote sensing data (radar altimetry and optical imagery) are used to highlight the potential of satellite data to monitor water resources: water height, areal extent and storage variations. New results from 20 years of monitoring using satellites over the Syrdarya basin are presented. The accuracy of satellite data is 0.6 km 3 using a combination of MODIS data and satellite altimetry, and only 0.2 km 3 with Landsat images representing 2–4% of average annual reservoir volume variations in the reservoirs in the Syrdarya basin. With future missions such as Sentinel-3A (S3A), Sentinel-3B (S3B) and surface water and ocean topography (SWOT), significant improvement is expected. The SWOT mission’s main payload (a radar interferometer in Ka band) will furthermore provide 2D maps of water height, reservoirs, lakes, rivers and floodplains, with a temporal resolution of 21 days. At the global scale, the SWOT mission will cover reservoirs with areal extents greater than 250  ×  250 m with 20 cm accuracy. (letter)

  15. Global surveys of reservoirs and lakes from satellites and regional application to the Syrdarya river basin

    Science.gov (United States)

    Jean-François, Crétaux; Sylvain, Biancamaria; Adalbert, Arsen; Muriel, Bergé-Nguyen; Mélanie, Becker

    2015-01-01

    Large reservoirs along rivers regulate downstream flows to generate hydropower but may also store water for irrigation and urban sectors. Reservoir management therefore becomes critical, particularly for transboundary basins, where coordination between riparian countries is needed. Reservoir management is even more important in semiarid regions where downstream water users may be totally reliant on upstream reservoir releases. If the water resources are shared between upstream and downstream countries, potentially opposite interests arise as is the case in the Syrdarya river in Central Asia. In this case study, remote sensing data (radar altimetry and optical imagery) are used to highlight the potential of satellite data to monitor water resources: water height, areal extent and storage variations. New results from 20 years of monitoring using satellites over the Syrdarya basin are presented. The accuracy of satellite data is 0.6 km3 using a combination of MODIS data and satellite altimetry, and only 0.2 km3 with Landsat images representing 2-4% of average annual reservoir volume variations in the reservoirs in the Syrdarya basin. With future missions such as Sentinel-3A (S3A), Sentinel-3B (S3B) and surface water and ocean topography (SWOT), significant improvement is expected. The SWOT mission’s main payload (a radar interferometer in Ka band) will furthermore provide 2D maps of water height, reservoirs, lakes, rivers and floodplains, with a temporal resolution of 21 days. At the global scale, the SWOT mission will cover reservoirs with areal extents greater than 250 × 250 m with 20 cm accuracy.

  16. Spatial Differentiation of Landscape Values in the Murray River Region of Victoria, Australia

    Science.gov (United States)

    Zhu, Xuan; Pfueller, Sharron; Whitelaw, Paul; Winter, Caroline

    2010-05-01

    This research advances the understanding of the location of perceived landscape values through a statistically based approach to spatial analysis of value densities. Survey data were obtained from a sample of people living in and using the Murray River region, Australia, where declining environmental quality prompted a reevaluation of its conservation status. When densities of 12 perceived landscape values were mapped using geographic information systems (GIS), valued places clustered along the entire river bank and in associated National/State Parks and reserves. While simple density mapping revealed high value densities in various locations, it did not indicate what density of a landscape value could be regarded as a statistically significant hotspot or distinguish whether overlapping areas of high density for different values indicate identical or adjacent locations. A spatial statistic Getis-Ord Gi* was used to indicate statistically significant spatial clusters of high value densities or “hotspots”. Of 251 hotspots, 40% were for single non-use values, primarily spiritual, therapeutic or intrinsic. Four hotspots had 11 landscape values. Two, lacking economic value, were located in ecologically important river red gum forests and two, lacking wilderness value, were near the major towns of Echuca-Moama and Albury-Wodonga. Hotspots for eight values showed statistically significant associations with another value. There were high associations between learning and heritage values while economic and biological diversity values showed moderate associations with several other direct and indirect use values. This approach may improve confidence in the interpretation of spatial analysis of landscape values by enhancing understanding of value relationships.

  17. Extending airborne electromagnetic surveys for regional active layer and permafrost mapping with remote sensing and ancillary data, Yukon Flats ecoregion, central Alaska

    Science.gov (United States)

    Pastick, Neal J.; Jorgenson, M. Torre; Wylie, Bruce K.; Minsley, Burke J.; Ji, Lei; Walvoord, Michelle Ann; Smith, Bruce D.; Abraham, Jared D.; Rose, Joshua R.

    2013-01-01

    Machine-learning regression tree models were used to extrapolate airborne electromagnetic resistivity data collected along flight lines in the Yukon Flats Ecoregion, central Alaska, for regional mapping of permafrost. This method of extrapolation (r = 0.86) used subsurface resistivity, Landsat Thematic Mapper (TM) at-sensor reflectance, thermal, TM-derived spectral indices, digital elevation models and other relevant spatial data to estimate near-surface (0–2.6-m depth) resistivity at 30-m resolution. A piecewise regression model (r = 0.82) and a presence/absence decision tree classification (accuracy of 87%) were used to estimate active-layer thickness (ALT) (remote sensing and map data. At site scale, the predicted ALTs were similar to those previously observed for different vegetation types. At the landscape scale, the predicted ALTs tended to be thinner on higher-elevation loess deposits than on low-lying alluvial and sand sheet deposits of the Yukon Flats. The ALT and permafrost maps provide a baseline for future permafrost monitoring, serve as inputs for modelling hydrological and carbon cycles at local to regional scales, and offer insight into the ALT response to fire and thaw processes.

  18. Geochemical evidence for seasonal controls on the transportation of Holocene loess, Matanuska Valley, southern Alaska, USA

    Science.gov (United States)

    Muhs, Daniel; Budahn, James R.; Skipp, Gary L.; McGeehin, John

    2016-01-01

    Loess is a widespread Quaternary deposit in Alaska and loess accretion occurs today in some regions, such as the Matanuska Valley. The source of loess in the Matanuska Valley has been debated for more than seven decades, with the Knik River and the Matanuska River, both to the east, being the leading candidates and the Susitna River, to the west, as a less favorable source. We report here new stratigraphic, mineralogic, and geochemical data that test the competing hypotheses of these river sources. Loess thickness data are consistent with previous studies that show that a source or sources lay to the east, which rules out the Susitna River as a source. Knik and Matanuska River silts can be distinguished using Sc–Th–La, LaN/YbN vs. Eu/Eu∗, Cr/Sc, and As/Sb. Matanuska Valley loess falls clearly within the range of values for these ratios found in Matanuska River silt. Dust storms from the Matanuska River are most common in autumn, when river discharge is at a minimum and silt-rich point bars are exposed, wind speed from the north is beginning to increase after a low-velocity period in summer, snow depth is still minimal, and soil temperatures are still above freezing. Thus, seasonal changes in climate and hydrology emerge as critical factors in the timing of aeolian silt transport in southern Alaska. These findings could be applicable to understanding seasonal controls on Pleistocene loess accretion in Europe, New Zealand, South America, and elsewhere in North America.

  19. Impacts of urban and industrial development on Arctic land surface temperature in Lower Yenisei River Region.

    Science.gov (United States)

    Li, Z.; Shiklomanov, N. I.

    2015-12-01

    Urbanization and industrial development have significant impacts on arctic climate that in turn controls settlement patterns and socio-economic processes. In this study we have analyzed the anthropogenic influences on regional land surface temperature of Lower Yenisei River Region of the Russia Arctic. The study area covers two consecutive Landsat scenes and includes three major cities: Norilsk, Igarka and Dudingka. Norilsk industrial region is the largest producer of nickel and palladium in the world, and Igarka and Dudingka are important ports for shipping. We constructed a spatio-temporal interpolated temperature model by including 1km MODIS LST, field-measured climate, Modern Era Retrospective-analysis for Research and Applications (MERRA), DEM, Landsat NDVI and Landsat Land Cover. Those fore-mentioned spatial data have various resolution and coverage in both time and space. We analyzed their relationships and created a monthly spatio-temporal interpolated surface temperature model at 1km resolution from 1980 to 2010. The temperature model then was used to examine the characteristic seasonal LST signatures, related to several representative assemblages of Arctic urban and industrial infrastructure in order to quantify anthropogenic influence on regional surface temperature.

  20. Summary of the Snake River plain Regional Aquifer-System Analysis in Idaho and eastern Oregon

    Science.gov (United States)

    Lindholm, G.F.

    1996-01-01

    Regional aquifers underlying the 15,600-square-mile Snake River Plain in southern Idaho and eastern Oregon was studied as part of the U.S. Geological Survey's Regional Aquifer-System Analysis program. The largest and most productive aquifers in the Snake River Plain are composed of Quaternary basalt of the Snake River Group, which underlies most of the 10,8000-square-mile eastern plain. Aquifer tests and simulation indicate that transmissivity of the upper 200 feet of the basalt aquifer in the eastern plain commonly ranges from about 100,000 to 1,000,000 feet squared per day. However, transmissivity of the total aquifer thickness may be as much as 10 million feet squared per day. Specific yield of the upper 200 feet of the aquifer ranges from about 0.01 to 0.20. Average horizontal hydraulic conductivity of the upper 200 feet of the basalt aquifer ranges from less than 100 to 9,000 feet per day. Values may be one to several orders of magnitude higher in parts in individual flows, such as flow tops. Vertical hydraulic conductivity is probably several orders of magnitude lower than horizontal hydraulic conductivity and is generally related to the number of joints. Pillow lava in ancestral Snake River channels has the highest hydraulic conductivity of all rock types. Hydraulic conductivity of the basalt decreases with depth because of secondary filling of voids with calcite and silica. An estimated 80 to 120 million acre-feet of water is believed to be stored in the upper 200 feet of the basalt aquifer in the eastern plain. The most productive aquifers in the 4,800-square-mile western plain are alluvial sand and gravel in the Boise River valley. Although aquifer tests indicate that transmissivity of alluvium in the Boise River valley ranges from 5,000 to 160,000 feet squared per day, simulation suggests that average transmissivity of the upper 500 feet is generally less than 20,000 feet squared per day. Vertically averaged horizontal hydraulic conductivity of the upper

  1. Dissolved inorganic carbon, total alkalinity, pH, nutrients, and other variables collected from surface only or profile discrete sampling observations using Niskin bottle and other instruments in the Gulf of Alaska region from 2007-05-19 to 2013-07-22 (NCEI Accession 0132049)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archival package includes environmental data from the Gulf of Alaska region. Samples were collected between May 2007 and July 2013.

  2. Regional hydrology of the Green River-Moab area, northwestern Paradox Basin, Utah

    International Nuclear Information System (INIS)

    Rush, F.E.; Whitfield, M.S.; Hart, I.M.

    1982-12-01

    The Green River-Moab area encompasses about 7800 square kilometers or about 25% of the Paradox basin. The entire Paradox basin is a part of the Colorado Plateaus that is underlain by a thick sequence of evaporite (salt) beds of Pennsylvanian age. The rock units that underlie the area have been grouped into hydrogeologic units based on their water-transmitting ability. Confining beds consist of evaporite beds of mostly salt, and overlying and underlying thick sequences of rocks with minimal permeability; above and below these confining beds are aquifers. The upper Mesozoic sandstone aquifer, probably is the most permeable hydrogeologic unit of the area and is the subject of this investigation. The principal component of groundwater outflow from this aquifer probably is subsurface flow to regional streams (the Green and Colorado Rivers) and is about 100 million cubic meters per year. All other components of outflow are relatively small. The average annual recharge to the aquifer is about 130 million cubic meters, of which about 20 million cubic meters is from local precipitation. For the lower aquifer, all recharge and discharge probably is by subsurface flow and was not estimated. The aquifers are generally isolated from the evaporite beds by the bounding confining beds; as a result, most ground water has little if any contact with the evaporites. Brines are present in the confining beds, but solution of beds of salt probably is very slow in most parts of the area. No brine discharges have been identified

  3. Ecological studies on the freshwater fishes of the Alligator Rivers region, Northern Territory

    International Nuclear Information System (INIS)

    Bishop, K.A.; Allen, S.A.; Pollard, D.A.; Cook, M.G.

    1990-01-01

    The tropical climate of the Alligator Rivers Region (ARR) has a distinctive wet-dry cycle , resulting in seasonal flows in the creeks and rivers of its catchments. The present study, begun in August 1978, was aimed at developing an ecological monitoring system that would detect any changes to the freshwater fish communities brought about by recent uranium mining and processing in the lowlands of the ARR. The focus of the synecological studies, was a description of spatial and temporal patterns in the community structure of the fish fauna. Interpretation of these patterns was made possible by the collection of detailed environmental data from the study sites. It was found that of the ARR seasonal changes in environmental conditions were so marked that they often obscured the effects of environmental gradients along a watercourse and differing environmental conditions characteristics of different types of waterbody. Hence it may not be entirely satisfactory to define environmental zones in these catchments based on overall environmental conditions through the whole seasonal cycle, because changes in any one such zone between seasons result in very marked changes in the fish communities of habitats in that zone. 34 refs., 22 tabs., 45 figs., 3 maps

  4. McCall Glacier record of Arctic climate change: Interpreting a northern Alaska ice core with regional water isotopes

    Science.gov (United States)

    Klein, E. S.; Nolan, M.; McConnell, J.; Sigl, M.; Cherry, J.; Young, J.; Welker, J. M.

    2016-01-01

    We explored modern precipitation and ice core isotope ratios to better understand both modern and paleo climate in the Arctic. Paleoclimate reconstructions require an understanding of how modern synoptic climate influences proxies used in those reconstructions, such as water isotopes. Therefore we measured periodic precipitation samples at Toolik Lake Field Station (Toolik) in the northern foothills of the Brooks Range in the Alaskan Arctic to determine δ18O and δ2H. We applied this multi-decadal local precipitation δ18O/temperature regression to ∼65 years of McCall Glacier (also in the Brooks Range) ice core isotope measurements and found an increase in reconstructed temperatures over the late-20th and early-21st centuries. We also show that the McCall Glacier δ18O isotope record is negatively correlated with the winter bidecadal North Pacific Index (NPI) climate oscillation. McCall Glacier deuterium excess (d-excess, δ2H - 8*δ18O) values display a bidecadal periodicity coherent with the NPI and suggest shifts from more southwestern Bering Sea moisture sources with less sea ice (lower d-excess values) to more northern Arctic Ocean moisture sources with more sea ice (higher d-excess values). Northern ice covered Arctic Ocean McCall Glacier moisture sources are associated with weak Aleutian Low (AL) circulation patterns and the southern moisture sources with strong AL patterns. Ice core d-excess values significantly decrease over the record, coincident with warmer temperatures and a significant reduction in Alaska sea ice concentration, which suggests that ice free northern ocean waters are increasingly serving as terrestrial precipitation moisture sources; a concept recently proposed by modeling studies and also present in Greenland ice core d-excess values during previous transitions to warm periods. This study also shows the efficacy and importance of using ice cores from Arctic valley glaciers in paleoclimate reconstructions.

  5. Impact of remote oceanic forcing on Gulf of Alaska sea levels and mesoscale circulation

    Science.gov (United States)

    Melsom, Arne; Metzger, E. Joseph; Hurlburt, Harley E.

    2003-11-01

    We examine the relative importance of regional wind forcing and teleconnections by an oceanic pathway for impact on interannual ocean circulation variability in the Gulf of Alaska. Any additional factors that contribute to this variability, such as freshwater forcing from river runoff, are disregarded. The study is based on results from numerical simulations, sea level data from tide gauge stations, and sea surface height anomalies from satellite altimeter data. At the heart of this investigation is a comparison of ocean simulations that include and exclude interannual oceanic teleconnections of an equatorial origin. Using lagged correlations, the model results imply that 70-90% of the interannual coastal sea level variance in the Gulf of Alaska can be related to interannual sea levels at La Libertad, Equador. These values are higher than the corresponding range from sea level data, which is 25-55%. When oceanic teleconnections from the equatorial Pacific are excluded in the model, the explained variance becomes about 20% or less. During poleward propagation the coastally trapped sea level signal in the model is less attenuated than the observed signal. In the Gulf of Alaska we find well-defined sea level peaks in the aftermath of El Niño events. The interannual intensity of eddies in the Gulf of Alaska also peaks after El Niño events; however, these maxima are less clear after weak and moderate El Niño events. The interannual variations in eddy activity intensity are predominantly governed by the regional atmospheric forcing.

  6. Geothermal energy in Alaska: site data base and development status

    Energy Technology Data Exchange (ETDEWEB)

    Markle, D.

    1979-04-01

    The following are presented: the history of geothermal energy in Alaska; a history of Alaska land ownership; legal and institutional barriers; and economics. Development, the socio-economic and physical data concerning geothermal energy are documented by regions. The six regions presented are those of the present Alaska State Planning Activities and those of the Federal Land Use Commission. Site data summaries of the one hundred and four separate geothermal spring locations are presented by these regions. (MHR)

  7. Science-policy interplay: Air quality management in the Pearl River Delta region and Hong Kong

    Science.gov (United States)

    Zhong, Liuju; Louie, Peter K. K.; Zheng, Junyu; Yuan, Zibing; Yue, Dingli; Ho, Josephine W. K.; Lau, Alexis K. H.

    2013-09-01

    The information provided by the scientific studies and control measures implemented in the Pearl River Delta (PRD) region of China reveals that tremendous progress has been made in the understanding of regional air pollution issues and the deployment of mitigation measures for alleviating these problems. Given the unparalleled rapid economic growth in the PRD over the past two decades, such progress was only made possible by strong, science-based support and the partnerships between government and research institutions in the region and overseas. Researchers from these partnership programs and related studies have deployed cutting-edge expertise and experience in various crucial mainland China and mainland China/Hong Kong-level projects. China recognizes the importance of protecting the environment and cleaning up the air in the pursuit of sustainable growth and economic development. To avoid falling into a cycle of event-driven clean-up efforts, China has recently taken a major step and updated the national ambient air quality standards. Clearly, China is implementing an increasing number of evidence-based policies to address air pollution problems. Thus, to bring a fresh impetus at a national level, the PRD must maintain and augment the Hong Kong-mainland collaborative momentum, inducing a "whole-China" effort to clean up air pollution. To strengthen the science-based support system and ensure continuous and concerted effort in implementing the regional multi-pollutant control strategy, there must be an overarching and integral Hong Kong-Guangdong science consortium framework supporting the formulation of regional policy and control measures built on common goals under the "one country, two systems" principle. The "PRD Approach" of the air quality management regime reflected regional cooperative efforts in synchronous air pollutant control, catalyzed the crucial role of information disclosure and subtly transformed the air quality management approach to overcome

  8. CSI : Alaska

    International Nuclear Information System (INIS)

    Letwin, S.

    2005-01-01

    This presentation emphasized the need for northern gas supply at a time when conventional natural gas supplies are decreasing and demand is growing. It highlighted the unique qualifications of Enbridge Inc. in creating an infrastructure to move the supply to where it is in most demand. Enbridge has substantial northern experience and has a unique approach for the construction of the Alaskan Gas Pipeline which entails cooperation, stability and innovation (CSI). Enbridge's role in the joint venture with AltaGas and Inuvialuit Petroleum was discussed along with its role in the construction of the first Canadian pipeline in 1985. The 540 mile pipeline was buried in permafrost. A large percentage of Enbridge employees are of indigenous descent. Enbridge recognizes that the amount of capital investment and the associated risk needed for the Alaska Gas Pipeline will necessitate a partnership of producers, pipeline companies, Native organizations, the State of Alaska, market participants and other interested parties. 9 figs

  9. Improving Shade Modelling in a Regional River Temperature Model Using Fine-Scale LIDAR Data

    Science.gov (United States)

    Hannah, D. M.; Loicq, P.; Moatar, F.; Beaufort, A.; Melin, E.; Jullian, Y.

    2015-12-01

    Air temperature is often considered as a proxy of the stream temperature to model the distribution areas of aquatic species water temperature is not available at a regional scale. To simulate the water temperature at a regional scale (105 km²), a physically-based model using the equilibrium temperature concept and including upstream-downstream propagation of the thermal signal was developed and applied to the entire Loire basin (Beaufort et al., submitted). This model, called T-NET (Temperature-NETwork) is based on a hydrographical network topology. Computations are made hourly on 52,000 reaches which average 1.7 km long in the Loire drainage basin. The model gives a median Root Mean Square Error of 1.8°C at hourly time step on the basis of 128 water temperature stations (2008-2012). In that version of the model, tree shadings is modelled by a constant factor proportional to the vegetation cover on 10 meters sides the river reaches. According to sensitivity analysis, improving the shade representation would enhance T-NET accuracy, especially for the maximum daily temperatures, which are currently not very well modelized. This study evaluates the most efficient way (accuracy/computing time) to improve the shade model thanks to 1-m resolution LIDAR data available on tributary of the LoireRiver (317 km long and an area of 8280 km²). Two methods are tested and compared: the first one is a spatially explicit computation of the cast shadow for every LIDAR pixel. The second is based on averaged vegetation cover characteristics of buffers and reaches of variable size. Validation of the water temperature model is made against 4 temperature sensors well spread along the stream, as well as two airborne thermal infrared imageries acquired in summer 2014 and winter 2015 over a 80 km reach. The poster will present the optimal length- and crosswise scale to characterize the vegetation from LIDAR data.

  10. Practical possibility to manage radiation pollution on the examples of the region of Krivoy Rog and Loire river

    Energy Technology Data Exchange (ETDEWEB)

    Sizonenko, V. [Institute of General Energy of NAS of Ukraine (Ukraine)

    2014-07-01

    Uranium deposit placed near-by Zoltje Vody City in the region of Krivoy Rog is one of most on territory of Ukraine. One of main mining objects of the city is a mine 'Nova', which works mine of ferrous and uranium ores. Mine water which is pumped out on a surface is saturated by uranium is used for the technological necessities of mining complex and finally is thrown down in a Zoltaja River. This results in contamination of waters of Ingulets River (tributary of the Dnieper River) and Karachunovskoe reservoir - of the basic source of water-supply of whole region. The paper will show possibilities for managing of possible consequences of accidental events of volley inflow of the muddy mine waters in Zoltaja River, prognostication of possible consequences of such catastrophic situations. The computer model of the water system of region Zoltje Vody City - Krivoy Rog City has been developed with usage of the new box model of incomplete inter-fusion with lagging argument. It gave the opportunity for accurate prognostication and short time of preparedness. Examples of prognostication of levels of concentrations of radionuclide ({sup 238}U) in waters of the Ingulets River, Zoltaja River and Karachunovskoe reservoir depending on the discharges of water of rivers and modes (regulation and catastrophic) of polluted water kick of mine 'Nova' are demonstrated. Possibilities of water protection actions are explored at the catastrophic discharge of mine water to Zoltaja River. Protection action is dilution by waters from the storage pool of Ingulets River. Such measures in many cases enable to access to safe and adequate water and sanitation services during the catastrophic events. The practical efforts for mitigation of consequences of the protracted catastrophic manmade influence on a water environment and possibilities of rehabilitation of the water system in the whole region of Krivoy Rog were analyzed in the work. The research of emissions tritium in the

  11. Estimating Error in SRTM Derived Planform of a River in Data-poor Region and Subsequent Impact on Inundation Modeling

    Science.gov (United States)

    Bhuyian, M. N. M.; Kalyanapu, A. J.

    2017-12-01

    Accurate representation of river planform is critical for hydrodynamic modeling. Digital elevation models (DEM) often falls short in accurately representing river planform because they show the ground as it was during data acquisition. But, water bodies (i.e. rivers) change their size and shape over time. River planforms are more dynamic in undisturbed riverine systems (mostly located in data-poor regions) where remote sensing is the most convenient source of data. For many of such regions, Shuttle Radar Topographic Mission (SRTM) is the best available source of DEM. Therefore, the objective of this study is to estimate the error in SRTM derived planform of a river in a data-poor region and estimate the subsequent impact on inundation modeling. Analysis of Landsat image, SRTM DEM and remotely sensed soil data was used to classify the planform activity in an 185 km stretch of the Kushiyara River in Bangladesh. In last 15 years, the river eroded about 4.65 square km and deposited 7.55 square km area. Therefore, current (the year 2017) river planform is significantly different than the SRTM water body data which represents the time of SRTM data acquisition (the year 2000). The rate of planform shifting significantly increased as the river traveled to downstream. Therefore, the study area was divided into three reaches (R1, R2, and R3) from upstream to downstream. Channel slope and meandering ratio changed from 2x10-7 and 1.64 in R1 to 1x10-4 and 1.45 in R3. However, more than 60% erosion-deposition occurred in R3 where a high percentage of Fluvisols (98%) and coarse particles (21%) were present in the vicinity of the river. It indicates errors in SRTM water body data (due to planform shifting) could be correlated with the physical properties (i.e. slope, soil type, meandering ratio etc.) of the riverine system. The correlations would help in zoning activity of a riverine system and determine a timeline to update DEM for a given region. Additionally, to estimate the

  12. VOCs and OVOCs distribution and control policy implications in Pearl River Delta region, China

    Science.gov (United States)

    Louie, Peter K. K.; Ho, Josephine W. K.; Tsang, Roy C. W.; Blake, Donald R.; Lau, Alexis K. H.; Yu, Jian Zhen; Yuan, Zibing; Wang, Xinming; Shao, Min; Zhong, Liuju

    2013-09-01

    Ambient air measurements of volatile organic compounds (VOCs) and oxygenated volatile organic compounds (OVOCs) were conducted and characterised during a two-year grid study in the Pearl River Delta (PRD) region of southern China. The present grid study pioneered the systematic investigation of the nature and characteristics of complex VOC and OVOC sources at a regional scale. The largest contributing VOCs, accounting over 80% of the total VOCs mixing ratio, were toluene, ethane, ethyne, propane, ethene, butane, benzene, pentane, ethylbenzene, and xylenes. Sub-regional VOC spatial characteristics were identified, namely: i) relatively fresh pollutants, consistent with elevated vehicular and industrial activities, around the PRD estuary; and ii) a concentration gradient with higher mixing ratios of VOCs in the west as compared with the eastern part of PRD. Based on alkyl nitrate aging determination, a high hydroxyl radical (OH) concentration favoured fast hydrocarbon reactions and formation of locally produced ozone. The photochemical reactivity analysis showed aromatic hydrocarbons and alkenes together consisted of around 80% of the ozone formation potential (OFP) among the key VOCs. We also found that the OFP from OVOCs should not be neglected since their OFP contribution was more than one-third of that from VOCs alone. These findings support the choice of current air pollution control policy which focuses on vehicular sources but warrants further controls. Industrial emissions and VOCs emitted by solvents should be the next targets for ground-level ozone abatement.

  13. Business, State of Alaska

    Science.gov (United States)

    Investment Advisors Business Law Charitable Gaming Division of Banking & Securities Laws Relating to Skip to content State of Alaska myAlaska My Government Resident Business in Alaska Visiting Alaska State Government Jobs Federal Jobs Starting a Small Business Living Get a Driver License Get a Hunting

  14. Alaska Community Transit

    Science.gov (United States)

    Grant Information Human Services Funding 5310 5316 (Repealed) 5317 (Repealed) Alaska Mental Health Trust Department of Transportation & Public Facilities/ Alaska Community Transit Search DOT&PF State of Alaska Photo banner DOT&PF> Program Development > Alaska Community Transit Home About Us

  15. Alaska State Trails Program

    Science.gov (United States)

    Recreation Search DNR State of Alaska Home Menu Parks Home Alaska State Trails Boating Safety Design and Home / Alaska State Trails Alaska State Trails Program Trails in the Spotlight Glacier Lake and Saddle Trails in Kachemak State Park Glacier Lake A Popular route joins the Saddle and Glacier Lake Trails. The

  16. Characteristics of carbonaceous aerosol in PM 2.5: Pearl Delta River Region, China

    Science.gov (United States)

    Huang, H.; Ho, K. F.; Lee, S. C.; Tsang, P. K.; Ho, Steven Sai Hang; Zou, C. W.; Zou, S. C.; Cao, J. J.; Xu, H. M.

    2012-02-01

    Simultaneous measurements of atmospheric organic carbon (OC), elemental carbon (EC) and water-soluble organic carbon (WSOC) were made at four sampling sites, namely Guangzhou (GZ), Zhaoqing (ZQ), PolyU Campus (PU) and Hok Tsui (HT), in the Pearl River Delta (PRD) region between 14 August 2006 and 28 August 2007. The highest concentrations of total carbon (TC) were found at the medium-scale roadside site (PU) and the lowest were found at the regional-scale site (HT). Among the four sampling sites, the average WSOC at ZQ showed the highest concentrations, while the lowest were seen at HT. OC and EC concentrations revealed spring/summer minima and autumn/winter maxima at all sites except PU, which had a consistently high EC concentration all over the year. The highest WSOC/OC ratio was found at ZQ with an average of 0.41, suggesting that the OC was more oxidized in the atmosphere of the semi-rural site. The lowest WSOC/OC was found at the roadside site of PU. Moreover, the WSOC/OC ratio increased in autumn, when the photochemical reactions are the most active in the PRD region. This can be attributed to aging and atmospheric processing of the organic compounds during their transportation, or to the formation of secondary organic aerosol (SOA). Average annual secondary organic carbon (SOC) concentrations in PM2.5 were estimated to be 2.2 and 3.5 μg m- 3 for GZ and ZQ, comprising 33.5% and 42.8% of the corresponding OC concentrations, respectively. The results indicate that SOC is significant in the PRD region, and its formation mostly occurs within the region.

  17. Recruiting first generation college students into the Geosciences: Alaska's EDGE project

    Science.gov (United States)

    Prakash, A.; Connor, C.

    2008-12-01

    Funded in 2005-2008, by the National Science Foundation's Geoscience Education Division, the Experiential Discoveries in Geoscience Education (EDGE) project was designed to use glacier and watershed field experiences as venues for geospatial data collected by Alaska's grade 6-12 middle and high school teachers and their students. EDGE participants were trained in GIS and learned to analyze geospatial data to answer questions about the warming Alaska environment and to determine rates of ongoing glacier recession. Important emphasis of the program was the recruitment of Alaska Native students of Inupiat, Yup'ik, Athabascan, and Tlingit populations, living in both rural and urban areas around the state. Twelve of Alaska's 55 school districts have participated in the EDGE program. To engage EDGE students in the practice of scientific inquiry, each was required to carry out a semester scale research project using georeferenced data, guided by their EDGE teacher and mentor. Across Alaska students investigated several Earth systems processes including freezing conditions of lake ice; the changes in water quality in storm drains after rainfall events; movements of moose, bears, and bison across Alaskan landscapes; changes in permafrost depth in western Alaska; and the response of migrating waterfowl to these permafrost changes. Students correlated the substrate beneath their schools with known earthquake intensities; measured cutbank and coastal erosion on northern rivers and southeastern shorelines; tracked salmon infiltration of flooded logging roads; noted the changing behavior of eagles during late winter salmon runs; located good areas for the use of tidal power for energy production; tracked the extent and range of invasive plant species with warming; and the change of forests following deglaciation. Each cohort of EDGE students and teachers finished the program by attended a 3-day EDGE symposium at which students presented their research projects first in a

  18. Evolution of regional stress state based on faulting and folding near the pit river, Shasta county, California

    Science.gov (United States)

    Austin, Lauren Jean

    We investigate the evolution of the regional stress state near the Pit River, northern California, in order to understand the faulting style in a tectonic transition zone and to inform the hazard analysis of Fault 3432 near the Pit 3 Dam. By analyzing faults and folds preserved in and adjacent to a diatomite mine north of the Pit River, we have determined principal stress directions preserved during the past million years. We find that the stress state has evolved from predominantly normal to strike slip and most recently to reverse, which is consistent with regional structures such as the extensional Hat Creek Fault to the south and the compressional folding of Mushroom Rock to the north. South of the Pit River, we still observe normal and strike slip faults, suggesting that changes in stress state are moving from north to south through time.

  19. Dissolution and Release of Gaseous Nitrogen (N2, N2O) in the Source Region of the Yellow River

    Science.gov (United States)

    Zhang, L.; Xia, X.; Wang, J.

    2017-12-01

    Nitrogen is an important biogenic element. The migration and transformation of nitrogen in rivers is an important process affecting global nitrogen cycling and greenhouse gas emissions. However, there is a lack of research on nitrogen removal and greenhouse gas emission characteristics of high altitude rivers. In this work, the spatial and temporal variations of dissolved nitrogen (N2 and N2O) concentrations, saturation, and release flux as well as their responses to environmental factors were studied in the Yellow River source area, a typical high altitude river. The results showed that the dissolved concentrations of N2 and N2O in the rivers were 8.24-137.75 μmol.L-1 and 2.57-31.94 nmol.L-1, respectively. N2 and N2O saturation were greater than 100% for all the sampling sites, indicating that the river is a release source for atmosphere N2 and N2O. Correspondingly, the fluxes of N2 and N2O from river water to atmosphere were 24.12-1606.57 mmol (m2.d) -1 and 12.96-276.81 μmol (m2.d) -1, respectively. Generally, the dissolution concentration and release flux of N2 and N2O in July were larger than that in May. The concentrations of N2 and N2O in river water were related to the environmental factors, and the dissolved concentration of N2 in the surface water was significantly positively correlated with water temperature, NH4+-N and total inorganic nitrogen (DIN) (p<0.01). The dissolved concentration of N2O was significantly positively correlated with the content of suspended particulates, DO, and DIN (p<0.01). Thus, DIN is a key factor in the process of N2 and N2O formation. This study can help to understand the nitrogen cycling in high-altitude rivers and provide basic data for a comprehensive assessment of global river nitrogen loss. Key Words: Source Region of the Yellow River; Gaseous Nitrogen; Nitrogen loss; High altitude river

  20. Resilience of Alaska's Boreal Forest to Climatic Change

    Science.gov (United States)

    Chapin, F. S., III; McGuire, A. D.; Ruess, R. W.; Hollingsworth, T. N.; Mack, M. C.; Johnstone, J. F.; Kasischke, E. S.; Euskirchen, E. S.; Jones, J. B.; Jorgenson, M. T.; hide

    2010-01-01

    This paper assesses the resilience of Alaska s boreal forest system to rapid climatic change. Recent warming is associated with reduced growth of dominant tree species, plant disease and insect outbreaks, warming and thawing of permafrost, drying of lakes, increased wildfire extent, increased postfire recruitment of deciduous trees, and reduced safety of hunters traveling on river ice. These changes have modified key structural features, feedbacks, and interactions in the boreal forest, including reduced effects of upland permafrost on regional hydrology, expansion of boreal forest into tundra, and amplification of climate warming because of reduced albedo (shorter winter season) and carbon release from wildfires. Other temperature-sensitive processes for which no trends have been detected include composition of plant and microbial communities, long-term landscape-scale change in carbon stocks, stream discharge, mammalian population dynamics, and river access and subsistence opportunities for rural indigenous communities. Projections of continued warming suggest that Alaska s boreal forest will undergo significant functional and structural changes within the next few decades that are unprecedented in the last 6000 years. The impact of these social ecological changes will depend in part on the extent of landscape reorganization between uplands and lowlands and on policies regulating subsistence opportunities for rural communities.

  1. Seasonally and regionally determined indication potential of bioassays in contaminated river sediments.

    Science.gov (United States)

    Hilscherová, Klára; Dusek, Ladislav; Sídlová, Tereza; Jálová, Veronika; Cupr, Pavel; Giesy, John P; Nehyba, Slavomír; Jarkovský, Jirí; Klánová, Jana; Holoubek, Ivan

    2010-03-01

    River sediments are a dynamic system, especially in areas where floods occur frequently. In the present study, an integrative approach is used to investigate the seasonal and spatial dynamics of contamination of sediments from a regularly flooded industrial area in the Czech Republic, which presents a suitable model ecosystem for pollutant distribution research at a regional level. Surface sediments were sampled repeatedly to represent two different hydrological situations: spring (after the peak of high flow) and autumn (after longer period of low flow). Samples were characterized for abiotic parameters and concentrations of priority organic pollutants. Toxicity was assessed by Microtox test; genotoxicity by SOS-chromotest and green fluorescent protein (GFP)-yeast test; and the presence of compounds with specific mode of action by in vitro bioassays for dioxin-like activity, anti-/androgenicity, and anti-/estrogenicity. Distribution of organic contaminants varied among regions and seasonally. Although the results of Microtox and genotoxicity tests were relatively inconclusive, all other specific bioassays led to statistically significant regional and seasonal differences in profiles and allowed clear separation of upstream and downstream regions. The outcomes of these bioassays indicated an association with concentrations of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) as master variables. There were significant interrelations among dioxin-like activity, antiandrogenicity and content of organic carbon, clay, and concentration of PAHs and PCBs, which documents the significance of abiotic factors in accumulation of pollutants. The study demonstrates the strength of the specific bioassays in indicating the changes in contamination and emphasizes the crucial role of a well-designed sampling plan, in which both spatial and temporal dynamics should be taken into account, for the correct interpretations of information in risk assessments.

  2. High resolution of black carbon and organic carbon emissions in the Pearl River Delta region, China.

    Science.gov (United States)

    Zheng, Junyu; He, Min; Shen, Xingling; Yin, Shasha; Yuan, Zibing

    2012-11-01

    A high-resolution regional black carbon (BC) and organic carbon (OC) emission inventory for the year 2009 was developed for the Pearl River Delta (PRD) region, China, based on the collected activity data and the latest emission factors. PM(2.5), BC and OC emissions were estimated to be 303 kt, 39 kt and 31 kt, respectively. Industrial processes were major contributing sources to PM(2.5) emissions. BC emissions were mainly from mobile sources, accounting for 65.0%, while 34.1% of OC emissions were from residential combustion. The primary OC/BC ratios for individual cities in the PRD region were dependent on the levels of economic development due to differences in source characteristics, with high ratios in the less developed cities and low ratios in the central and southern developed areas. The preliminary temporal profiles were established, showing the highest OC emissions in winter and relatively constant BC emissions throughout the year. The emissions were spatially allocated into grid cells with a resolution of 3 km × 3 km. Large amounts of BC emissions were distributed over the central-southern PRD city clusters, while OC emissions exhibited a relatively even spatial distribution due to the significant biomass burning emissions from the outlying area of the PRD region. Uncertainties in carbonaceous aerosol emissions were usually higher than in other primary pollutants like SO(2), NO(x), and PM(10). One of the key uncertainty sources was the emission factor, due to the absence of direct measurements of BC and OC emission rates. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Regional Ecological Risk Assessment in the Huai River Watershed during 2010–2015

    Directory of Open Access Journals (Sweden)

    Yan Lu

    2017-12-01

    Full Text Available Ecosystem deterioration has been and is still a serious threat to human survival and regional economic development. Theoretical and methodological challenges exist in assessing ecological risk of watershed ecosystem that is imposed by natural changes or human activities. To fill this research gap, this research proposes an interdisciplinary and quantitative methodology based on some techniques such as the Procedure for Ecological Tiered Assessment of Risk (PETAR, the Entropy, and the Celluar Automata Markov (CA-Markov. We focused on six vulnerable environmental variables, namely land-use change, water quantity, water quality, gross domestic product (GDP, environmental pollutants, and soil erosion in the Huai River watershed in the Henan Province in order to build multi-dimensional quantitative method. Further, the Coupling Coordination Degree Model is constructed, and the “threshold index” is also addressed to reflect the limitation of ecological risk. Our results show that the spatio-temperal distribution of the eco-environmental quality has greatly varied across this study area during different time spans. Natural eco-environmental quality has moderately degraded in 70% of this study area (mainly agricultural region, at a prefectural level from 2000 to 2010, and has slightly improved over the agricultural region (<170 m above sea level during 2010–2015. However, when considering negative stressors from human social system on the natural ecosystem, the extent and distribution of the ecological risk varied across the whole area during 2000–2015. The results show that there was almost 90.40% of this region under the ecological risk, with varying extents over the study time, e.g., Kaifeng, Shangqiu, Xuchang, and Xinyang, with a moderate deterioration in the eco-environmental quality, and Zhengzhou with a slight deterioration in the eco-environmental quality. This paper provides a valuable perspective for governments at all levels to manage

  4. Towards a publicly available, map-based regional software tool to estimate unregulated daily streamflow at ungauged rivers

    Directory of Open Access Journals (Sweden)

    S. A. Archfield

    2013-01-01

    Full Text Available Streamflow information is critical for addressing any number of hydrologic problems. Often, streamflow information is needed at locations that are ungauged and, therefore, have no observations on which to base water management decisions. Furthermore, there has been increasing need for daily streamflow time series to manage rivers for both human and ecological functions. To facilitate negotiation between human and ecological demands for water, this paper presents the first publicly available, map-based, regional software tool to estimate historical, unregulated, daily streamflow time series (streamflow not affected by human alteration such as dams or water withdrawals at any user-selected ungauged river location. The map interface allows users to locate and click on a river location, which then links to a spreadsheet-based program that computes estimates of daily streamflow for the river location selected. For a demonstration region in the northeast United States, daily streamflow was, in general, shown to be reliably estimated by the software tool. Estimating the highest and lowest streamflows that occurred in the demonstration region over the period from 1960 through 2004 also was accomplished but with more difficulty and limitations. The software tool provides a general framework that can be applied to other regions for which daily streamflow estimates are needed.

  5. Towards a publicly available, map-based regional software tool to estimate unregulated daily streamflow at ungauged rivers

    Science.gov (United States)

    Archfield, Stacey A.; Steeves, Peter A.; Guthrie, John D.; Ries, Kernell G.

    2013-01-01

    Streamflow information is critical for addressing any number of hydrologic problems. Often, streamflow information is needed at locations that are ungauged and, therefore, have no observations on which to base water management decisions. Furthermore, there has been increasing need for daily streamflow time series to manage rivers for both human and ecological functions. To facilitate negotiation between human and ecological demands for water, this paper presents the first publicly available, map-based, regional software tool to estimate historical, unregulated, daily streamflow time series (streamflow not affected by human alteration such as dams or water withdrawals) at any user-selected ungauged river location. The map interface allows users to locate and click on a river location, which then links to a spreadsheet-based program that computes estimates of daily streamflow for the river location selected. For a demonstration region in the northeast United States, daily streamflow was, in general, shown to be reliably estimated by the software tool. Estimating the highest and lowest streamflows that occurred in the demonstration region over the period from 1960 through 2004 also was accomplished but with more difficulty and limitations. The software tool provides a general framework that can be applied to other regions for which daily streamflow estimates are needed.

  6. K-Ar geology, geochemistry and geochronology from the Maria River region dikes, Parana State southeastern part, Brazil

    International Nuclear Information System (INIS)

    Silva Junior, Renato Oliveira da; Dall'Agnol, Roberto; Oliveira, Elson Paiva de

    1996-01-01

    The paper synthesizes the geological, petrographical, geochemical and geochronological data from the Maria River region dikes, situated at the southeastern part of the Para State, Brazil. It identifies five groups of dikes and determines the age of these dikes, through the Potassium-Argon (K-Ar) methodology

  7. Paleoecology of late-glacial peats from the bering land bridge, Chukchi Sea shelf region, northwestern Alaska

    Science.gov (United States)

    Elias, S.A.; Short, S.K.; Phillips, R.L.

    1992-01-01

    Insect fossils and pollen from late Pleistocene nonmarine peat layers were recovered from cores from the shelf region of the Chukchi Sea at depths of about 50 m below sea level. The peats date to 11,300-11,000 yr B.P. and provide a limiting age for the regional Pleistocene-Holocene marine transgression. The insect fossils are indicative of arctic coastal habitats like those of the Mackenzie Delta region (mean July temperatures = 10.6-14??C) suggesting that 11,000 yr ago the exposed Chukchi Sea shelf had a climate substantially warmer than modern coastal regions of the Alaskan north slope. The pollen spectra are consistent with the age assignment to the Birch Interval (14,000-9000 yr B.P.). The data suggest a meadow-like graminoid tundra with birch shrubs and some willow shrubs growing in sheltered areas. ?? 1992.

  8. Volatile Organic Compound (VOC) measurements in the Pearl River Delta (PRD) region, China

    Science.gov (United States)

    Liu, Ying; Shao, Min; Lu, Sihua; Chang, Chih-Chung; Wang, Jia-Lin; Chen, Gao

    2008-03-01

    We measured levels of ambient volatile organic compounds (VOCs) at seven sites in the Pearl River Delta (PRD) region of China during the Air Quality Monitoring Campaign spanning 4 October to 3 November 2004. Two of the sites, Guangzhou (GZ) and Xinken (XK), were intensive sites at which we collected multiple daily canister samples. The observations reported here provide a look at the VOC distribution, speciation, and photochemical implications in the PRD region. Alkanes constituted the largest percentage (>40%) in mixing ratios of the quantified VOCs at six sites; the exception was one major industrial site that was dominated by aromatics (about 52%). Highly elevated VOC levels occurred at GZ during two pollution episodes; however, the chemical composition of VOCs did not exhibit noticeable changes during these episodes. We calculated the OH loss rate to estimate the chemical reactivity of all VOCs. Of the anthropogenic VOCs, alkenes played a predominant role in VOC reactivity at GZ, whereas the contributions of reactive aromatics were more important at XK. Our preliminary analysis of the VOC correlations suggests that the ambient VOCs at GZ came directly from local sources (i.e., automobiles); those at XK were influenced by both local emissions and transportation of air mass from upwind areas.

  9. Emergy Synthesis and Regional Sustainability Assessment: Case Study of Pan-Pearl River Delta in China

    Directory of Open Access Journals (Sweden)

    Guomin Li

    2014-08-01

    Full Text Available In this paper, emergy analysis is used in association with the ternary diagrams and geographic information system (GIS tools to improve the evaluation of sustainability for the Pan-Pearl River Delta (PPRD region. Emergy accounting of PPRD is estimated, and various emergy-based indicators are reported. Ternary diagrams are drawn to provide a graphical representation of the emergy accounting data. Finally, the GIS tools are employed to assist in the emergy-based spatial analysis, and emergy density based on flat land area is mapped to reflect the intensity of emergy use in human activity areas. Results show the following: (1 the current development path of the PPRD region, with the value of emergy sustainability index (ESI = 0.227 significantly lower than one, is unsustainable in the long run; (2 Guangdong has the lowest ESI value (0.071, and the ESI values of Fujian, Guangxi, Hunan and Jiangxi are lower than 0.5, indicating that the economy in these provinces overly relies on non-renewable and imported resources; (3 Guizhou has a high emergy yield rate and is thus the main energy supplier in PPRD; and (4 among the nine provinces in PPRD, only Hainan has an ESI value (2.145 higher than one.

  10. Estimation of underground river water availability based on rainfall in the Maros karst region, South Sulawesi

    Science.gov (United States)

    Arsyad, Muhammad; Ihsan, Nasrul; Tiwow, Vistarani Arini

    2016-02-01

    Maros karst region, covering an area of 43.750 hectares, has water resources that determine the life around it. Water resources in Maros karst are in the rock layers or river underground in the cave. The data used in this study are primary and secondary data. Primary data includes characteristics of the medium. Secondary data is rainfall data from BMKG, water discharge data from the PSDA, South Sulawesi province in 1990-2010, and the other characteristics data Maros karst, namely cave, flora and fauna of the Bantimurung Bulusaraung National Park. Data analysis was conducted using laboratory test for medium characteristics Maros karst, rainfall and water discharge were analyzed using Minitab Program 1.5 to determine their profile. The average rainfall above 200 mm per year occurs in the range of 1999 to 2005. The availability of the water discharge at over 50 m3/s was happened in 1993 and 1995. Prediction was done by modeling Autoregressive Integrated Moving Average (ARIMA), with the rainfall data shows that the average precipitation for four years (2011-2014) will sharply fluctuate. The prediction of water discharge in Maros karst region was done for the period from January to August in 2011, including the type of 0. In 2012, the addition of the water discharge started up in early 2014.

  11. Geochemical evolution of groundwater in the Western Delta region of River Godavari, Andhra Pradesh, India

    Science.gov (United States)

    Nageswara Rao, P. V.; Appa Rao, S.; Subba Rao, N.

    2017-05-01

    The present study on geochemical evolution of groundwater is taken up to assess the controlling processes of water chemistry in the Western Delta region of the River Godavari (Andhra Pradesh), which is one of the major rice-producing centers in India. The study region is underlain by coarse sand with black clay (buried channels), black silty clay of recent origin (floodplain) and gray/white fine sand of modern beach sediment of marine source (coastal zone), including brown silty clay with fine sand (paleo-beach ridges). Groundwater is mostly brackish and very hard. It is characterized by Na+ > Mg2+ > Ca2+:HCO3 - > Cl- > SO4 2- > NO3 -, Na+ > Mg2+ > Ca2+:Cl- > HCO3 - > SO4 2-, and Mg2+ > Na+ > Ca2+ > or Cl- > or > SO4 2- facies. The ionic relations (Ca2+ + Mg2+:HCO3 -, Ca2+ + Mg2+:SO4 2- + HCO3 -, Na+ + K+:TC, Na+ + K+:Cl- + SO4 2-, HCO3 -:TC, HCO3 -:Ca2+ + Mg2+, Na+:Cl- and Na+:Ca2+) indicate that the rock weathering, mineral dissolution, evaporation and ion exchange are the processes to control the aquifer chemistry. Anthropogenic and marine sources are also the supplementary factors for brackish water quality. These observations are further supported by Gibbs mechanisms that control the water chemistry. Thus, the study suggests that the initial quality of groundwater of geogenic origin has been subsequently modified by the influences of anthropogenic and marine sources.

  12. DDT concentration in fish from the Tapajós River in the Amazon region, Brazil.

    Science.gov (United States)

    Mendes, Rosivaldo de Alcântara; Lopes, Anna Sylmara da Costa; de Souza, Larissa Costa; Lima, Marcelo de Oliveira; Santos, Lourivaldo da Silva

    2016-06-01

    DDT and metabolites were measured in six species of fish collected from the Tapajós River in the village of Barreiras, near the town of Itaituba in the Brazilian Amazon region. The selected fish were the most consumed and economically important to the local people. DDT was used frequently in this region for malaria control. Fish samples were analyzed after extraction by microwave-assisted extraction in hexane/acetone (8:2, v/v) by gas chromatography with electron capture detector. Residues of op'-DDT and pp'-DDT and metabolites were detected, including pp'-DDE, pp'-DDD, op'-DDT, and op'-DDE, in 98% of the samples, with a greater abundance of pp'-DDT. Total DDT levels were 7.1-249.5 ng g(-1) wet weight (w.w). The DDE/DDT ratio was low, indicating recent exposure to DDT. The study area that may be related to generated waste used in public health campaigns to combat mosquitos (Anopheles spp.), still present in the Amazon environment, that transmit malaria. DDT levels and metabolites found in fish species do not present risks to human health because they are below acceptable limits for consumption. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Expected changes in future temperature extremes and their elevation dependency over the Yellow River source region

    Directory of Open Access Journals (Sweden)

    Y. Hu

    2013-07-01

    Full Text Available Using the Statistical DownScaling Model (SDSM and the outputs from two global climate models, we investigate possible changes in mean and extreme temperature indices and their elevation dependency over the Yellow River source region for the two future periods 2046–2065 and 2081–2100 under the IPCC SRES A2, A1B and B1 emission scenarios. Changes in interannual variability of mean and extreme temperature indices are also analyzed. The validation results show that SDSM performs better in reproducing the maximum temperature-related indices than the minimum temperature-related indices. The projections show that by the middle and end of the 21st century all parts of the study region may experience increases in both mean and extreme temperature in all seasons, along with an increase in the frequency of hot days and warm nights and with a decrease in frost days. By the end of the 21st century, interannual variability increases in all seasons for the frequency of hot days and warm nights and in spring for frost days while it decreases for frost days in summer. Autumn demonstrates pronounced elevation-dependent changes in which around six out of eight indices show significant increasing changes with elevation.

  14. Simulation of the Impacts of Urbanization on Winter Meteorological Fields over the Pearl River Delta Region

    Directory of Open Access Journals (Sweden)

    Naixing Luo

    2017-01-01

    Full Text Available The influences of urbanization on weather in Guangdong Province, China, were studied using the Weather Research and Forecasting model from 31 December 2009 through 3 January 2010. Model outputs were compared with extensive monitoring of meteorological data to examine the simulation ability. Model results between tests (with and without land-use change show that the urbanization had major effects on meteorological fields across nearly the entire Pearl River Delta region and particularly in urban areas. Studied fields (wind speed, temperature, precipitation, and sensible and latent heat fluxes were affected by the urbanization of the PRD region. The major influences occurred in urban areas, where wind speeds decreased greatly, while the daytime surface upward sensible heat flux clearly increased. Unlike the sensible heat flux, the latent heat flux had a nonmonotonic increase or decrease. As a consequence of the two heat fluxes, 2-m temperature varied with location and time. Change of precipitation was complex. The main rain band became more concentrated, while precipitation decreased upwind of the urban area and increased downwind.

  15. Regional Frequency Analysis of Extreme Dry Spells during Rainy Season in the Wei River Basin, China

    Directory of Open Access Journals (Sweden)

    Dunxian She

    2016-01-01

    Full Text Available Our research analyzes the regional changes of extreme dry spell, represented by the annual maximum dry spell length (noted as AMDSL during the rainy season in the Wei River Basin (WRB of China for 1960–2014 using the L-moments method. The mean AMDSL values increase from the west to the east of the WRB, suggesting a high dry risk in the east compared to the west in the WRB. To investigate the regional frequency more reasonably, the WRB is clustered into four homogenous subregions via the K-means method and some subjective adjustments. The goodness-of-fit test shows that the GEV, PE3, and GLO distribution can be accepted as the “best-fit” model for subregions 1 and 4, subregion 2, and subregion 3, respectively. The quantiles of AMDSL under various return levels figure out a similar spatial distribution with mean AMDSL. We also find that the dry risk in subregion 2 and subregion 4 might be higher than that in subregion 1. The relationship between ENSO events and extreme dry spell events in the rainy season with cross wavelet analysis method proves that ENSO events play a critical role in triggering extreme dry events during rainy season in the WRB.

  16. Volatile Organic Compound (VOC measurements in the Pearl River Delta (PRD region, China

    Directory of Open Access Journals (Sweden)

    Chih-chung Chang

    2008-03-01

    Full Text Available We measured levels of ambient volatile organic compounds (VOCs at seven sites in the Pearl River Delta (PRD region of China during the Air Quality Monitoring Campaign spanning 4 October to 3 November 2004. Two of the sites, Guangzhou (GZ and Xinken (XK, were intensive sites at which we collected multiple daily canister samples. The observations reported here provide a look at the VOC distribution, speciation, and photochemical implications in the PRD region. Alkanes constituted the largest percentage (>40% in mixing ratios of the quantified VOCs at six sites; the exception was one major industrial site that was dominated by aromatics (about 52%. Highly elevated VOC levels occurred at GZ during two pollution episodes; however, the chemical composition of VOCs did not exhibit noticeable changes during these episodes. We calculated the OH loss rate to estimate the chemical reactivity of all VOCs. Of the anthropogenic VOCs, alkenes played a predominant role in VOC reactivity at GZ, whereas the contributions of reactive aromatics were more important at XK. Our preliminary analysis of the VOC correlations suggests that the ambient VOCs at GZ came directly from local sources (i.e., automobiles; those at XK were influenced by both local emissions and transportation of air mass from upwind areas.

  17. Regional tree growth and inferred summer climate in the Winnipeg River basin, Canada, since AD 1783

    Science.gov (United States)

    St. George, Scott; Meko, David M.; Evans, Michael N.

    2008-09-01

    A network of 54 ring-width chronologies is used to estimate changes in summer climate within the Winnipeg River basin, Canada, since AD 1783. The basin drains parts of northwestern Ontario, northern Minnesota and southeastern Manitoba, and is a key area for hydroelectric power production. Most chronologies were developed from Pinus resinosa and P. strobus, with a limited number of Thuja occidentalis, Picea glauca and Pinus banksiana. The dominant pattern of regional tree growth can be recovered using only the nine longest chronologies, and is not affected by the method used to remove variability related to age or stand dynamics from individual trees. Tree growth is significantly, but weakly, correlated with both temperature (negatively) and precipitation (positively) during summer. Simulated ring-width chronologies produced by a process model of tree-ring growth exhibit similar relationships with summer climate. High and low growth across the region is associated with cool/wet and warm/dry summers, respectively; this relationship is supported by comparisons with archival records from early 19th century fur-trading posts. The tree-ring record indicates that summer droughts were more persistent in the 19th and late 18th century, but there is no evidence that drought was more extreme prior to the onset of direct monitoring.

  18. Stream fish colonization but not persistence varies regionally across a large North American river basin

    Science.gov (United States)

    Wheeler, Kit; Wengerd, Seth J.; Walsh, Stephen J.; Martin, Zachary P.; Jelks, Howard L.; Freeman, Mary C.

    2018-01-01

    Many species have distributions that span distinctly different physiographic regions, and effective conservation of such taxa will require a full accounting of all factors that potentially influence populations. Ecologists recognize effects of physiographic differences in topography, geology and climate on local habitat configurations, and thus the relevance of landscape heterogeneity to species distributions and abundances. However, research is lacking that examines how physiography affects the processes underlying metapopulation dynamics. We used data describing occupancy dynamics of stream fishes to evaluate evidence that physiography influences rates at which individual taxa persist in or colonize stream reaches under different flow conditions. Using periodic survey data from a stream fish assemblage in a large river basin that encompasses multiple physiographic regions, we fit multi-species dynamic occupancy models. Our modeling results suggested that stream fish colonization but not persistence was strongly governed by physiography, with estimated colonization rates considerably higher in Coastal Plain streams than in Piedmont and Blue Ridge systems. Like colonization, persistence was positively related to an index of stream flow magnitude, but the relationship between flow and persistence did not depend on physiography. Understanding the relative importance of colonization and persistence, and how one or both processes may change across the landscape, is critical information for the conservation of broadly distributed taxa, and conservation strategies explicitly accounting for spatial variation in these processes are likely to be more successful for such taxa.

  19. Heavy metal contamination in some mining communities within the Jimi River basin in Ashanti Region, Ghana

    International Nuclear Information System (INIS)

    Akabzaa, T.M.; Banoeng-Yakubu, B.; Seyire, J.S.

    2005-01-01

    The study assesses heavy metals contamination of some communities along the Jim River Basin in the Ashanti Region. The Jim River Basin is within the mining concession of Ashanti Goldfields Company (AGC) Limited, now Anglogold Ashanti. The selected communities receive drainage and effluent from mining, processing and waste containment facilities of AGC and from the activities of illegal small scale miners (galamseys) in the area. Representative samples of water from streams, boreholes, hand-dug wells, stream and over bank sediments, and fruits were analyzed for Mn, Cu, Zn, Ni, Pb and Cd using the Unicam 969 Atomic Absorption Spectrometer (AAS). Fe was determined by ion chromatography, As by an ARL 341 hydride-generator and Hg by cold vapour Atomic Fluorescence Spectrometry. Protracted periods of underground mining, recent extensive surface mining and intensified illegal mining activities were identified as major sources of augmented levels of heavy metals in water, sediment and fruit samples. Sediments and fruits exhibit higher concentration of determined metals than water. Cu, Cd, Zn, and Ni, are generally low in water samples, while Fe, As and Mn are generally high, particularly in stream water and ranged from < 0.002 to 17.100mg/l, 0.001 to 6.318mg/l and <0.001 to 2.584mg/l respectively. Metal concentrations were highest in sediments. Fe values in sediments ranged from 2210-50180 mg/kg and averaged 28270mg/kg, Hg between 0.26 to 3.02 mg/kg and averaged 1.21mg/kg while arsenic ranged between 0.24-to 7591.58mg/kg and averaged 1746.51mg/kg. Heavy metals in fruit samples were considered indicative of their bioavailability. Some fruits showed extremely high concentrations Hg, Zn and As. High heavy metal concentrations are generally coincident with areas of past and/ or of active mining and processing activities. (author)

  20. Modeling Regional Soil Water Balance in Farmland of the Middle Reaches of Heihe River Basin

    Directory of Open Access Journals (Sweden)

    Jiang Li

    2017-11-01

    Full Text Available Quantifying components of soil water balance in farmland of the middle reaches of Heihe River Basin is essential for efficiently scheduling and allocating limited water resources for irrigation in this arid region. A soil water balance model based on empirical assumptions in the vadose zone of farmland was developed and simulation results were compared/validated with results by the numerical model HYDRUS-1D. Results showed a good coherence between the simulated results of the water balance models and the HYDRUS-1D model in soil water storage, evapotranspiration, deep percolation and groundwater recharge, which indicated that the water balance model was suitable for simulating soil water movement in the study area. Considering the spatial distribution of cropping patterns, groundwater depth and agricultural management, ArcGIS was applied for the pre-/post-processing of the water balance model to quantify the spatial distribution of components of soil water balance in the major cropland in middle reaches of Heihe River Basin. Then, distributions of components of soil water balance in the major cropland under different water-saving irrigation practices during the growing season were predicted and discussed. Simulation results demonstrated that evapotranspiration of the main crops would be more prominently influenced by irrigation quota under deep groundwater depth than that under shallow groundwater depth. Groundwater recharge would increase with the increase of irrigation quota and decrease with the increase of groundwater depth. In general, when groundwater depth reached 3 m, groundwater recharge from root zone was negligible for spring wheat. While when it reached 6 m, groundwater recharge was negligible for maize. Water-saving irrigation practices would help to reduce groundwater recharge with a slight decrease of crop water consumption.

  1. An Experience of Statistical Method Application in Forest Survey at Angara River Region in 1932

    Directory of Open Access Journals (Sweden)

    L. N. Vashchuk

    2014-10-01

    Full Text Available Report of the Angara forest economic expedition of forest economic survey in 1932 on the left bank of the Angara River has been found. The survey covered a part of Krasnoyarsk Territory and Irkutsk region, a total area of 18641.8 thousand ha. The report describes technology of forest inventory and achievements that have not previously been published. The survey was conducted by statistical method, which consisted of a sample by a continuous forest inventory enumeration of trees on sample plots (SP, arranged in an array on a particular system, followed by mathematical-statistical recalculation of the sample results to the entire survey. To do this, strip finders (sights were cut in the latitudinal direction at a distance from one another at 16 km. On the hacked sights, by every 2 km, 0.1 ha (10 × 100 m SP were established. In total 32 forest inventory sights were hacked, with total length of 9931 km, which incorporated 4817 SP. The accuracy of forest resources’ inventory characteristics determining also was investigated using smaller sample plots. For this purpose, each of the SP were cut to smaller area of 0.01 ha (10 × 10 m, where independent continuous enumeration of trees was conducted, andsample trees were cut, measured and bucked to the assortments, to explore the tree stand assortment structure. At each «sample cutting area» all the trees were felled out from 44 cm and above DBH. At half of the sample plot with 5 × 10 m size, located in the eastern end, all the trees were felled out and measured from 24 cm and above DBH. Every four «sample cutting area» in the fifth, all the trees with 12 cm and above DBH were cut down and measured. According to the results of the work, a detailed description of forest resources in the whole Angara river basin, and across 17 forest exploitation areas was completed.

  2. Lower Colorado River Geographic Response Plan Restricted Web Mapping Service, Region 9, 2012, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — This map service is comprised of data related to Geographic Response Plans (GRPs) for the Lower Colorado River. Data layers were contributed by various stakeholders...

  3. Regional severe particle pollution and its association with synoptic weather patterns in the Yangtze River Delta region, China

    Science.gov (United States)

    Shu, Lei; Xie, Min; Gao, Da; Wang, Tijian; Fang, Dexian; Liu, Qian; Huang, Anning; Peng, Liwen

    2017-11-01

    Regional air pollution is significantly associated with dominant weather systems. In this study, the relationship between the particle pollution over the Yangtze River Delta (YRD) region and weather patterns is investigated. First, the pollution characteristics of particles in the YRD are studied using in situ monitoring data (PM2.5 and PM10) in 16 cities and Terra/MODIS AOD (aerosol optical depth) products collected from December 2013 to November 2014. The results show that the regional mean value of AOD is high in the YRD, with an annual mean value of 0.71±0.57. The annual mean particle concentrations in the cities of Jiangsu Province all exceed the national air quality standard. The pollution level is higher in inland areas, and the highest concentrations of PM2.5 and PM10 are 79 and 130 µg m-3, respectively, in Nanjing. The PM2.5 : PM10 ratios are typically high, thus indicating that PM2.5 is the overwhelmingly dominant particle pollutant in the YRD. The wintertime peak of particle concentrations is tightly linked to the increased emissions during the heating season as well as adverse meteorological conditions. Second, based on NCEP (National Center for Environmental Prediction) reanalysis data, synoptic weather classification is conducted and five typical synoptic patterns are objectively identified. Finally, the synthetic analysis of meteorological fields and backward trajectories are applied to further clarify how these patterns impact particle concentrations. It is demonstrated that air pollution is more or less influenced by high-pressure systems. The relative position of the YRD to the anti-cyclonic circulation exerts significant effects on the air quality of the YRD. The YRD is largely influenced by polluted air masses from the northern and the southern inland areas when it is located at the rear of the East Asian major trough. The significant downward motion of air masses results in stable weather conditions, thereby hindering the diffusion of air

  4. Observations of the vegetation of the Atigun River floodplain as affected by the crude oil spill from the Trans-Alaska Pipeline

    Data.gov (United States)

    Department of the Interior — This report is a summary of the results of botanical investigation conducted along the Atigun River, associated side channels and tributaries during the period 26 –...

  5. Hydrochemical and isotopic studies in two neighboring river basins in semiarid regions of Minas Gerais

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Vinícius G.; Moreira, Rubens M.; Carvalho, Carlos A., E-mail: vinicius.ferreira@cdtn.br, E-mail: rubens@cdtn.br, E-mail: cacf@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Serviço de Meio Ambiente

    2017-07-01

    Groundwater is the largest reservoir of fresh water on Earth and the depletion of aquifer systems is a reality, both in semi-arid and humid regions. The hydrology of watersheds is a field of study that is concerned with the movement of waters from the rains and its physical-chemical changes. Groundwater resources in these regions are a sensitive issue, requiring careful management to avoid quality degradation. The present study focuses the groundwater system at the interface of the Pandeiros and Peruaçu river basins in the northwest region of Minas Gerais State. The methods used were the evaluations of the hydrochemistry, as well as isotopic, and physicochemical parameters, allied to geological studies to investigate surface and groundwater, their possible interactions and spatial distribution. The hydrochemical results correlated with the physicochemical measurements show water contrasts in the study area, which is geologically composed from bottom to top by gneisses and granites (Januaria Complex), limestone and siltstones (Bambuí Group), sandstones and eluvial sediments (Urucuia Group), eluvio-coluvial cover and alluvial deposits. It has been observed that waters in the context of sandstones and siliceous sediments are sodium bicarbonate waters, slightly acidic pH and low in TDS, whereas waters in pedological / geologic context of limestones are calcium bicarbonate waters exhibiting basic pH and high TDS. The deuterium (D) and oxygen-18 signatures of the groundwater are compared to the global meteoric water line (GMWL). The average values of the isotopes in the study area are slightly variable, indicating that the isotopic signatures are related to rainfall precipitation. It has been possible to suggest an evaporation line pattern starting from the position of springs, passing though streams and finally ending in the lagoon. The local evaporation line can be represented by the equation δD = 5,8 δ{sup 18}O - 2,4. (author)

  6. Regionalizing Aquatic Ecosystems Based on the River Subbasin Taxonomy Concept and Spatial Clustering Techniques

    Directory of Open Access Journals (Sweden)

    Jiahu Zhao

    2011-11-01

    Full Text Available Aquatic ecoregions were increasingly used as spatial units for aquatic ecosystem management at the watershed scale. In this paper, the principle of including land area, comprehensiveness and dominance, conjugation and hierarchy were selected as regionalizing principles. Elevation and drainage density were selected as the regionalizing indicators for the delineation of level I aquatic ecoregions, and percent of construction land area, percent of cultivated land area, soil type and slope for the level II. Under the support of GIS technology, the spatial distribution maps of the two indicators for level I and the four indicators for level II aquatic ecoregion delineation were generated from the raster data based on the 1,107 subwatersheds. River subbasin taxonomy concept, two-step spatial clustering analysis approach and manual-assisted method were used to regionalize aquatic ecosystems in the Taihu Lake watershed. Then the Taihu Lake watershed was divided into two level I aquatic ecoregions, including Ecoregion I1 and Ecoregion I2, and five level II aquatic subecoregions, including Subecoregion II11, Subecoregion II12, Subecoregion II21, Subecoregion II22 and Subecoregion II23. Moreover, the characteristics of the two level I aquatic ecoregions and five level II aquatic subecoregions in the Taihu Lake watershed were summarized, showing that there were significant differences in topography, socio-economic development, water quality and aquatic ecology, etc. The results of quantitative comparison of aquatic life also indicated that the dominant species of fish, benthic density, biomass, dominant species, Shannon-Wiener diversity index, Margalef species richness index, Pielou evenness index and ecological dominance showed great spatial variability between the two level I aquatic ecoregions and five level II aquatic subecoregions. It reflected the spatial heterogeneities and the uneven natures of aquatic ecosystems in the Taihu Lake watershed.

  7. 'Extra-regional' strike-slip fault systems in Chile and Alaska: the North Pacific Rim orogenic Stream vs. Beck's Buttress

    Science.gov (United States)

    Redfield, T. F.; Scholl, D. W.; Fitzgerald, P. G.

    2010-12-01

    The ~2000 km long Denali Fault System (DFS) of Alaska is an example of an extra-regional strike-slip fault system that terminates in a zone of widely-distributed deformation. The ~1200 km long Liquiñe-Ofqui Fault Zone (LOFZ) of Patagonia (southern Chile) is another. Both systems are active, having undergone large-magnitude seismic rupture is 2002 (DFS) and 2007 (LOFZ). Both systems appear to be long-lived: the DFS juxtaposes terranes that docked in at least early Tertiary time, whilst the central LOFZ appears to also record early Tertiary or Mesozoic deformation. Both fault systems comprise a relatively well-defined central zone where individual fault traces can be identified from topographic features or zones of deformed rock. In both cases the proximal and distal traces are much more diffuse tributary and distributary systems of individual, branching fault traces. However, since their inception the DFS and LOFZ have followed very different evolutionary paths. Copious Alaskan paleomagnetic data are consistent with vertical axis small block rotation, long-distance latitudinal translation, and a recently-postulated tectonic extrusion towards a distributary of subordinate faults that branch outward towards the Aleution subduction zone (the North Pacific Rim orogenic Stream; see Redfield et al., 2007). Paleomagnetic data from the LOFZ region are consistent with small block rotation but preclude statistically-significant latitudinal transport. Limited field data from the southernmost LOFZ suggest that high-angle normal and reverse faults dominate over oblique to strike-slip structures. Rather than the high-angle oblique 'slivering regime' of the southeasternmost DFS, the initiation of the LOFZ appears to occur across a 50 to 100 km wide zone of brittly-deformed granitic and gneissic rock characterized by bulk compression and vertical pathways of exhumation. In both cases, relative plate motions are consistent with the hypothetical style, and degree, of offset, leading

  8. Temporal fluctuation of multidrug resistant salmonella typhi haplotypes in the mekong river delta region of Vietnam.

    Directory of Open Access Journals (Sweden)

    Kathryn E Holt

    2011-01-01

    Full Text Available typhoid fever remains a public health problem in Vietnam, with a significant burden in the Mekong River delta region. Typhoid fever is caused by the bacterial pathogen Salmonella enterica serovar Typhi (S. Typhi, which is frequently multidrug resistant with reduced susceptibility to fluoroquinolone-based drugs, the first choice for the treatment of typhoid fever. We used a GoldenGate (Illumina assay to type 1,500 single nucleotide polymorphisms (SNPs and analyse the genetic variation of S. Typhi isolated from 267 typhoid fever patients in the Mekong delta region participating in a randomized trial conducted between 2004 and 2005.the population of S. Typhi circulating during the study was highly clonal, with 91% of isolates belonging to a single clonal complex of the S. Typhi H58 haplogroup. The patterns of disease were consistent with the presence of an endemic haplotype H58-C and a localised outbreak of S. Typhi haplotype H58-E2 in 2004. H58-E2-associated typhoid fever cases exhibited evidence of significant geo-spatial clustering along the Sông H u branch of the Mekong River. Multidrug resistance was common in the established clone H58-C but not in the outbreak clone H58-E2, however all H58 S. Typhi were nalidixic acid resistant and carried a Ser83Phe amino acid substitution in the gyrA gene.the H58 haplogroup dominates S. Typhi populations in other endemic areas, but the population described here was more homogeneous than previously examined populations, and the dominant clonal complex (H58-C, -E1, -E2 observed in this study has not been detected outside Vietnam. IncHI1 plasmid-bearing S. Typhi H58-C was endemic during the study period whilst H58-E2, which rarely carried the plasmid, was only transient, suggesting a selective advantage for the plasmid. These data add insight into the outbreak dynamics and local molecular epidemiology of S. Typhi in southern Vietnam.

  9. Radionuclide content in the Upper Vistula River sediments in a coal mining region in Poland (east-central Europe)

    International Nuclear Information System (INIS)

    Jasinska, M.; Mietelski, J.W.; Pociask-Karteczka, J.

    1998-01-01

    Hard coal mining activity is one of the Technologically Enhanced Natural Radiation sources introduced more than a hundred years ago in the southern part of Poland. This study of radionuclides (K-40, Ra-226, Ra-228) in river sediments showed the principal factors determining the specific activity of radionuclides are distance from mines and sorption by clay particles in river sediments. The K-40 specific activity varies between 185 and 595 Bq/kg. The highest Ra-228 and Ra-226 specific activities, 280-610 and 205-415 Bq/kg, respectively, were detected in sediments of the Vistula in the vicinity of Silesia region. 7 refs., 1 fig., 3 tabs

  10. Alaska Child Support Services Division

    Science.gov (United States)

    Payments Online! The CSSD Business Services Portal offers employers the convenience of paying child support ://my.Alaska.gov. Reporting online will save you time and money! If your business already has a myAlaska account Skip to content State of Alaska myAlaska My Government Resident Business in Alaska Visiting Alaska

  11. Early mixed farming of millet and rice 7800 years ago in the Middle Yellow River region, China.

    Directory of Open Access Journals (Sweden)

    Jianping Zhang

    Full Text Available The Peiligang Culture (9000-7000 cal. yr BP in the Middle Yellow River region, North China, has long been considered representative of millet farming. It is still unclear, however, if broomcorn millet or foxtail millet was the first species domesticated during the Peiligang Culture. Furthermore, it is also unknown whether millet was cultivated singly or together with rice at the same period. In this study, phytolith analysis of samples from the Tanghu archaeological site reveals early crop information in the Middle Yellow River region, China. Our results show that broomcorn millet was the early dry farming species in the Peiligang Culture at 7800 cal. yr BP, while rice cultivation took place from 7800 to 4500 cal. yr BP. Our data provide new evidence of broomcorn millet and rice mixed farming at 7800 cal. yr BP in the Middle Yellow River region, which has implications for understanding the domestication process of the two crops, and the formation and continuance of the Ancient Yellow River Civilization.

  12. Flood Zoning Simulation by HEC-RAS Model (Case Study: Johor River-Kota Tinggi Region)

    OpenAIRE

    ShahiriParsa, Ahmad; Heydari, Mohammad; Sadeghian, Mohammad Sadegh; Moharrampour, Mahdi

    2015-01-01

    Flooding of rivers has caused many human and financial losses. Hence, studies and research on the nature of the river is inevitable.However, the behavior of rivers hasmany complexities and in this respect, computer models are efficient tools in order to study and simulate the behavior of rivers with the least possible cost. In this paper, one-dimensional model HEC-RAS was used to simulate the flood zoning in the Kota Tinggi district in Johor state. Implementation processes of the zoning on ca...

  13. Geologic map of the upper Arkansas River valley region, north-central Colorado

    Science.gov (United States)

    Kellogg, Karl S.; Shroba, Ralph R.; Ruleman, Chester A.; Bohannon, Robert G.; McIntosh, William C.; Premo, Wayne R.; Cosca, Michael A.; Moscati, Richard J.; Brandt, Theodore R.

    2017-11-17

    This 1:50,000-scale U.S. Geological Survey geologic map represents a compilation of the most recent geologic studies of the upper Arkansas River valley between Leadville and Salida, Colorado. The valley is structurally controlled by an extensional fault system that forms part of the prominent northern Rio Grande rift, an intra-continental region of crustal extension. This report also incorporates new detailed geologic mapping of previously poorly understood areas within the map area and reinterprets previously studied areas. The mapped region extends into the Proterozoic metamorphic and intrusive rocks in the Sawatch Range west of the valley and the Mosquito Range to the east. Paleozoic rocks are preserved along the crest of the Mosquito Range, but most of them have been eroded from the Sawatch Range. Numerous new isotopic ages better constrain the timing of both Proterozoic intrusive events, Late Cretaceous to early Tertiary intrusive events, and Eocene and Miocene volcanic episodes, including widespread ignimbrite eruptions. The uranium-lead ages document extensive about 1,440-million years (Ma) granitic plutonism mostly north of Buena Vista that produced batholiths that intruded an older suite of about 1,760-Ma metamorphic rocks and about 1,700-Ma plutonic rocks. As a result of extension during the Neogene and possibly latest Paleogene, the graben underlying the valley is filled with thick basin-fill deposits (Dry Union Formation and older sediments), which occupy two sub-basins separated by a bedrock high near the town of Granite. The Dry Union Formation has undergone deep erosion since the late Miocene or early Pliocene. During the Pleistocene, ongoing steam incision by the Arkansas River and its major tributaries has been interrupted by periodic aggradation. From Leadville south to Salida as many as seven mapped alluvial depositional units, which range in age from early to late Pleistocene, record periodic aggradational events along these streams that are

  14. Geochronology of granitoids and gnaisses from the Rio Maria, Mata Geral farm and Itacaiunas river regions, southern Para, Brazil

    International Nuclear Information System (INIS)

    Montalvao, R.M.G. de; Tassinari, C.C.G.; Bezerra, P.E.L.; Prado, P.

    1984-01-01

    Granitoids and gneisses occurring at Rio Maria, Mata Geral farm and Itacaiunas river regions, southern Para, underwent radiometric age determinations by Rb/Sr method using conventional isochrons. Results obtained from the Rio Maria and Mata Geral farm regions allowed te establishment of a reference 2,600 my Rb/Sr isochron with an initial Sr 87 /Sr 86 ratio of 0.7009. This result resembles the one obtained for granitoids and gneisses hosting rocks of the Serra do Inaja greenstone belt, located some what south of this area, which yielded, in Rb/Sr isochron, a radiometric age of 2,696 + - 79 my with an initial Sr 87 /Sr 86 ratio of 0.701. Results obtained from the Itacaiunas river region allowed for the establishment of a Rb/Sr referential isochron of 2,480 + - 40 my wth an initial Sr 87 /.Sr 86 ratio of 0.7072. Due to low initial ratios, it is suggested that the rocks from the Rio Maria, Mata Geral farm and Serra do Inaja regions formed from Mafic crust or superior mantle reworking, while those from the Itacaiunas river region, due to a high initial ratio, result from reworking at high crustal levels. (Author) [pt

  15. Hydrogeological modelling of the eastern region of Areco river locally detailed on Atucha I and II nuclear power plants area

    International Nuclear Information System (INIS)

    Grattone, Natalia I.; Fuentes, Nestor O.

    2009-01-01

    Water flow behaviour of Pampeano aquifer was modeled using Visual Mod-flow software Package 2.8.1 with the assumption of a free aquifer, within the region of the Areco river and extending to the rivers of 'Canada Honda' and 'de la Cruz'. Steady state regime was simulated and grid refinement allows obtaining locally detailed calculation in the area of Atucha I and II Nuclear power plants, in order to compute unsteady situations as the consequence of water flow variations from and to the aquifer, enabling the model to study the movement of possible contaminant particles in the hydrogeologic system. In this work the effects of rivers action, the recharge conditions and the flow lines are analyzed, taking always into account the range of reliability of obtained results, considering the incidence of uncertainties introduced by data input system, the estimates and interpolation of parameters used. (author)

  16. Provision of educational service with the use of distance technologies for disabled persons (case study: the state of Alaska and Nothern regions of the Russian Federation

    Directory of Open Access Journals (Sweden)

    V. A. Lipatov

    2016-01-01

    Full Text Available The distance education contributes to the solution of educational problems of disabled persons. The study of foreign experience is extremely important. North American universities saved up a wide experience in this sphere. Unlike self-made software products created by many Russian universities, Blackboard is the leading educational software package that professionally helps to solve educational problems of disabled persons. The international University of the Arctic has a growing interest in the use of information communication technologies and open educational resources and networks. In 2008 the subject network of University of the Arctic on distance education and e-learning began to function. The Internet and distance learning creates a new opportunity for disabled persons. Main goal: Whether distance education on Alaska and in Northern and Siberian regions of the Russian Federation promotes the solution of educational problems of the North for disabled persons. Main research problems: to reveal modern educational Arctic problems for disabled persons; to analyse specifics of remote education; to analyse a question of distance training of the circumpolar North; to carry out the comparative analysis of distance training on Alaska and in Russian northern and the Siberian regions; to analyse a contribution of distance training to wider problems of the Arctic policy and management. Relevance of work: The Arctic Human Development Report I specifi es that there are very few circumpolar researches in the fi eld of education, including for disabled persons. This article can begin initial discussion of a subject which can be in addition studied in future works. An emerging trend for Arctic education is its increasing accessibility. Accessibility is about students being able to take classes and fulfi ll their potential, that is, it concerns their possibilities for attending school, both physically and culturally. Even though this

  17. Comparison of sediment pollution in the rivers of the Hungarian Upper Tisza Region using non-destructive analytical techniques

    International Nuclear Information System (INIS)

    Osan, Janos; Toeroek, Szabina; Alfoeldy, Balint; Alsecz, Anita; Falkenberg, Gerald; Baik, Soo Yeun; Van Grieken, Rene

    2007-01-01

    The rivers in the Hungarian Upper Tisza Region are frequently polluted mainly due to mining activities in the catchment area. At the beginning of 2000, two major mining accidents occurred in the Romanian part of the catchment area due to the failure of a tailings dam releasing huge amounts of cyanide and heavy metals to the rivers. Surface sediment as well as water samples were collected at six sites in the years 2000-2003, from the northeast-Hungarian section of the Tisza, Szamos and Tur rivers. The sediment pollution of the rivers was compared based on measurements of bulk material and selected single particles, in order to relate the observed compositions and chemical states of metals to the possible sources and weathering of pollution. Non-destructive X-ray analytical methods were applied in order to obtain different kinds of information from the same samples or particles. In order to identify the pollution sources, their magnitude and fate, complementary analyses were carried out. Heterogeneous particulate samples were analyzed from a large geographical territory and a 4-year time period. Individual particles were analyzed only from the 'hot' samples that showed elevated concentrations of heavy metals. Particles that were classified as anthropogenic were finally analyzed to identify trace concentrations and chemical states of heavy metals. Although the Tisza river was affected by water pollution due to the two major mining accidents at the beginning of 2000, the concentration of heavy metals in sediments decreased to the mineral background level 1 year after the pollution event. In the tributaries Szamos and Tur, however, no significant decrease of the heavy metal concentrations was observed in the recent years, indicating a continuous pollution. Among the water suspended particles collected from river Tur, fibers of unknown origin were observed by electron microscopy; these particles were aluminosilicates enriched in Zn and Mn. Cd was also concentrated in

  18. Hydrologic cycle and dynamics of aquatic macrophytes in two intermittent rivers of the semi-arid region of Brazil

    Directory of Open Access Journals (Sweden)

    F. Pedro

    Full Text Available The dynamics of aquatic macrophytes in intermittent rivers is generally related to the characteristics of the resistance and resilience of plants to hydrologic disturbances of flood and drought. In the semi-arid region of Brazil, intermittent rivers and streams are affected by disturbances with variable intensity, frequency, and duration throughout their hydrologic cycles. The aim of the present study is to determine the occurrence and variation of biomass of aquatic macrophyte species in two intermittent rivers of distinct hydrologic regimes. Their dynamics were determined with respect to resistance and resilience responses of macrophytes to flood and drought events by estimating the variation of biomass and productivity throughout two hydrologic cycles. Twenty-one visits were undertaken in the rewetting, drying, and drought phases in a permanent puddle in the Avelós stream and two temporary puddles in the Taperoá river, state of Paraíba, Northeast Brazil. The sampling was carried out by using the square method. Floods of different magnitudes occurred during the present study in the river and in the stream. The results showed that floods and droughts are determining factors in the occurrence of macrophytes and in the structure of their aquatic communities. The species richness of the aquatic macrophyte communities was lower in the puddles of the river and stream subject to flood events, when compared to areas where the run-off water is retained. At the beginning of the recolonization process, the intensity of the floods was decisive in the productivity and biomass of the aquatic macrophytes in the Taperoá river and the Avelós stream. In intermediate levels of disturbance, the largest values of productivity and biomass and the shortest time for starting the recolonization process occurred.

  19. On the Relationship between Holocene Geomorphic Evolution of Rivers and Prehistoric Settlements Distribution in the Songshan Mountain Region of China

    Directory of Open Access Journals (Sweden)

    Peng Lu

    2017-01-01

    Full Text Available This paper deals with the study of Holocene geomorphic evolution of rivers around Songshan Mountain in relation to human frequentation in Prehistoric periods. The investigations were performed by means of an integration of GIS data processing; field surveys and particle size analysis. In 8000–3000 aBP; in the Songshan Mountain Region, large-scale river sedimentation occurred. This increased the elevation of river beds that were higher than today. After 3000 aBP; the upper reaches of the rivers experienced a down cut; while the lower reaches experienced continuing sedimentation. The data on the elevation of prehistoric settlements above the river levels were obtained from Digital Elevation Models (DEMs. These data were corrected according to the evolutionary features of fluvial landforms in order to obtain synchronous elevations above river levels of prehistoric settlements. The relationship between sediment distribution and the Holocene geomorphic evolution was investigated through the statistical analysis of the elevation above the river levels. Outputs from our analyses enabled us to differentiate three evolutionary stages. During the first one, related to Peiligang culture (9000–7500 aBP, populations mainly settled on both hilly relief and high plateaus depending on their agriculture production modes. During the second stage, from Yangshao (7500–5000 aBP to the Longshan period (5000–4000 aBP, settlements were mainly distributed on mountainous areas and hilly lands to avoid flooding and to develop agriculture. Finally, during the Xiashang culture (4000–3000 aBP, a large number of settlements migrated to the plain area to facilitate trade of goods and cultural exchanges.

  20. Identification of fish nursery areas in a free tributary of an impoundment region, upper Uruguay River, Brazil

    Directory of Open Access Journals (Sweden)

    Patrícia Alves da Silva

    Full Text Available This study aims to determine the importance of different environments of the Ligeiro River (upper Uruguay River, Brazil in fish reproduction. For this purpose, three environments (sampling sites were selected: rapids, a pool, and the mouth of the Ligeiro River. Ichthyoplankton, zooplankton, and benthos were sampled six times per month from September, 2006 to March, 2007. Zooplankton and ichthyoplankton samples were collected early in the evening with plankton nets (64 µm and 500 µm, respectively. Benthos samples were also collected early in the evening with a Van Veen dredge. Local abiotic variables (temperature, dissolved oxygen, pH, electrical conductivity, water speed, alkalinity, water hardness, and water transparency were measured simultaneously with the biotic data sampling and were complemented by regional variables (water flow and precipitation. A total of 43,475 eggs and 2,269 larvae were captured. Of these larvae, 80.1% were in the pre-flexion and larval yolk stages. Digestive tract content showed that the greatest degree of repletion among the larvae in more advanced phases occurred in the pool environment. Water speed was the main characteristic used to differentiate the river's rapids and mouth from the pool. The abundance of zooplankton and benthos was not related to the distribution of densities among the different components of the ichthyoplankton. A greater abundance of eggs and larvae with yolk was found in the rapids and river mouth. Ordination analyses showed a connection between the advanced stage larvae and the pool environment. In conclusion, the rapids and river mouth of the Ligeiro River's are important locations for fish reproduction, particularly in regard to spawning and drifting of the ichthyoplankton's initial stages, whereas the pool represents a nursery place for larval growth.

  1. Assessment of regional air quality resulting from emission control in the Pearl River Delta region, southern China.

    Science.gov (United States)

    Wang, N; Lyu, X P; Deng, X J; Guo, H; Deng, T; Li, Y; Yin, C Q; Li, F; Wang, S Q

    2016-12-15

    To evaluate the impact of emission control measures on the air quality in the Pearl River Delta (PRD) region of South China, statistic data including atmospheric observations, emissions and energy consumptions during 2006-2014 were analyzed, and a Weather Research and Forecasting - Community Multi-scale Air Quality (WRF-CMAQ) model was used for various scenario simulations. Although energy consumption doubled from 2004 to 2014 and vehicle number significantly increased from 2006 to 2014, ambient SO 2 , NO 2 and PM 10 were reduced by 66%, 20% and 24%, respectively, mainly due to emissions control efforts. In contrast, O 3 increased by 19%. Model simulations of three emission control scenarios, including a baseline (a case in 2010), a CAP (a case in 2020 assuming control strength followed past control tendency) and a REF (a case in 2020 referring to the strict control measures based on recent policy/plans) were conducted to investigate the variations of air pollutants to the changes in NO x , VOCs and NH 3 emissions. Although the area mean concentrations of NO x , nitrate and PM 2.5 decreased under both NO x CAP (reduced by 1.8%, 0.7% and 0.2%, respectively) and NO x REF (reduced by 7.2%, 1.8% and 0.3%, respectively), a rising of PM 2.5 was found in certain areas as reducing NO x emissions elevated the atmospheric oxidizability. Furthermore, scenarios with NH 3 emission reductions showed that nitrate was sensitive to NH 3 emissions, with decreasing percentages of 0-10.6% and 0-48% under CAP and REF, respectively. Controlling emissions of VOCs reduced PM 2.5 in the southwestern PRD where severe photochemical pollution frequently occurred. It was also found that O 3 formation in PRD was generally VOCs-limited while turned to be NO x -limited in the afternoon (13:00-17:00), suggesting that cutting VOCs emissions would reduce the overall O 3 concentrations while mitigating NO x emissions in the afternoon could reduce the peak O 3 levels. Copyright © 2016 Elsevier B

  2. [Work-related accidents in traditional fishermen from the Medium Araguaia River region, Tocantins, Brazil].

    Science.gov (United States)

    Garrone Neto, Domingos; Cordeiro, Ricardo Carlos; Haddad, Vidal

    2005-01-01

    This is a cross-sectional study of work-related accidents among traditional fishermen in the Medium Araguaia River region of Tocantins, Brazil. From June to August 2002, fishermen from the Municipality of Araguacema were interviewed about the organization of their work activities and work-related accidents during the previous six months. Of the 92 participating fishermen, 56 reported having suffered a work-related accident (annual incidence was 82.6%). Some 95.7% of those interviewed did not regularly pay social security insurance as self-employed workers and were not aware of their social rights and duties. For fishermen reporting accidents, this proportion was 98.2%. Approximately 23.0% had another work activity, mainly as construction workers (47.6%) or sport-fishing guides (23.9%). Injuries inflicted by aquatic animals were the main form of accidents (about 86.0%). From these results, it is apparent that accidents from aquatic animals are an important health hazard, in some cases causing temporary work incapacity.

  3. Quebec region's shoreline segmentation in the St. Lawrence River : response tool for oil spills

    International Nuclear Information System (INIS)

    Laforest, S.; Martin, V.

    2004-01-01

    Environment Canada, the Canadian Coast Guard, and the Eastern Canada Response Corporation are developing and refining pre-spill databases containing information about physical shoreline characteristics. Automated links between these pre-spill shoreline characteristic databases and computerized shoreline assessment tools have also been created using Geographical Information System (GIS) technology. The pre-spill databases can be used for planning shoreline cleanup operations. A training exercise, designed to evaluate a spill management system integrating the Quebec region pre-spill shoreline database and the ShoreAssess R shoreline assessment system was performed by Eastern Canada Response Corporation during an aerial survey where shoreline was segmented into digitized information. The cartography of segmentation covers the fluvial part of the St. Lawrence River. The oil spill-oriented database includes geomorphologic information from the supratidal to the lower intertidal zones. It also includes some statistical information and other requirements for cleanup operations. The computerized shoreline assessment tools made it possible to evaluate the length and type of shoreline that would potentially be impacted by oil. The tools also made it possible to assess the shoreline treatment methods most likely to be used, and evaluate the probable duration of the cleanup operation. The training exercise demonstrated that the integration of the databases is a valuable tool during the early phases of an oil spill response. 9 refs., 3 figs

  4. Environmental lead pollution threatens the children living in the Pearl River Delta region, China.

    Science.gov (United States)

    Chen, Jianmin; Tong, Yongpeng; Xu, Jiazhang; Liu, Xiaoli; Li, Yulan; Tan, Mingguang; Li, Yan

    2012-09-01

    The objective of this study is to determine children's blood lead levels and identify sources of lead exposure. Childhood lead exposure constitutes a major pediatric health problem today in China. A blood lead screening survey program for children in the age group of 2-12 years residing in Pearl River Delta region, south of China, was carried out from Dec 2007 to Jan 2008. Blood lead levels and lead isotope ratios of a total of 761 participants were assessed by inductively coupled plasma mass spectroscopy. Measurements of urban environmental samples for source identification of children lead exposure were also performed. The geometric mean value of the children's blood lead levels was 57.05 μg/L, and 9.6% of them were higher than 100 μg/L. The blood lead levels were still much higher than those in developed countries. Based on the data of environmental lead source inventories, lead isotopic tracing revealed that there is about 6.7% past used gasoline Pb embedded in Shenzhen residential dust and about 15.6% in Guangzhou dust, respectively.

  5. River-damming, late-Quaternary rockslides in the Ötz Valley region (Tyrol, Austria)

    Science.gov (United States)

    Dufresne, A.; Ostermann, M.; Preusser, F.

    2018-06-01

    The Ötz Valley and adjacent regions in Tyrol (Austria) have been repeatedly affected by large rockslope failures following deglaciation. Six rockslides, each over 107 m3 in volume, were emplaced into the Ötz and Inn valleys, five of which formed persistent rockslide dams. Even though catastrophic rockslope failures are short-lived events (commonly minutes) they can have long-lasting impacts on the landscape. For example, large fans have built in the Ötz Valley and knickpoints persist at the former dam sites even though the Ötz River has eroded through the deposits during the past thousands of years; exact age-constraints of rockslide dam failure, however, are still scarce. Empirical, geomorphic stability indices from the literature successfully identified the least and the most stable dams of this group, whereas the rest remain inconclusive with some indices variably placing the dams in the stable, unstable, and uncertain categories. This shows (a) that further index calibrations and (b) better age constraints on dam formation and failure are needed, and (c) that the exact processes of dam failure are not always trivial to pinpoint for ancient (partially) breached dams. This study is a contribution towards better constraining the nature and landscape impact of dam formation following large rockslope failures.

  6. Regional-scale controls on dissolved nitrous oxide in the Upper Mississippi River

    Science.gov (United States)

    Turner, P.A.; Griffis, T.J.; Baker, J.M.; Lee, X.; Crawford, John T.; Loken, Luke C.; Venterea, R.T.

    2016-01-01

    The U.S. Corn Belt is one of the most intensive agricultural regions of the world and is drained by the Upper Mississippi River (UMR), which forms one of the largest drainage basins in the U.S. While the effects of agricultural nitrate (NO3-) on water quality in the UMR have been well documented, its impact on the production of nitrous oxide (N2O) has not been reported. Using a novel equilibration technique, we present the largest data set of freshwater dissolved N2O concentrations (0.7 to 6 times saturation) and examine the controls on its variability over a 350 km reach of the UMR. Driven by a supersaturated water column, the UMR was an important atmospheric N2O source (+68 mg N2ONm-2 yr-1) that varies nonlinearly with the NO3-concentration. Our analyses indicated that a projected doubling of the NO3-concentration by 2050 would cause dissolved N2O concentrations and emissions to increase by about 40%.

  7. A database of radionuclide activity and metal concentrations for the Alligator Rivers Region uranium province.

    Science.gov (United States)

    Doering, Che; Bollhöfer, Andreas

    2016-10-01

    This paper presents a database of radionuclide activity and metal concentrations for the Alligator Rivers Region (ARR) uranium province in the Australian wet-dry tropics. The database contains 5060 sample records and 57,473 concentration values. The data are for animal, plant, soil, sediment and water samples collected by the Environmental Research Institute of the Supervising Scientist (ERISS) as part of its statutory role to undertake research and monitoring into the impacts of uranium mining on the environment of the ARR. Concentration values are provided in the database for 11 radionuclides ( 227 Ac, 40 K, 210 Pb, 210 Po, 226 Ra, 228 Ra, 228 Th, 230 Th, 232 Th, 234 U, 238 U) and 26 metals (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Rb, S, Sb, Se, Sr, Th, U, V, Zn). Potential uses of the database are discussed. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  8. Developing a Validated Long-Term Satellite-Based Albedo Record in the Central Alaska Range to Improve Regional Hydroclimate Reconstructions

    Science.gov (United States)

    Kreutz, K. J.; Godaire, T. P.; Burakowski, E. A.; Winski, D.; Campbell, S. W.; Wang, Z.; Sun, Q.; Hamilton, G. S.; Birkel, S. D.; Wake, C. P.; Osterberg, E. C.; Schaaf, C.

    2015-12-01

    Mountain glaciers around the world, particularly in Alaska, are experiencing significant surface mass loss from rapid climatic shifts and constitute a large proportion of the cryosphere's contribution to sea level rise. Surface albedo acts as a primary control on a glacier's mass balance, yet it is difficult to measure and quantify spatially and temporally in steep, mountainous settings. During our 2013 field campaign in Denali National Park to recover two surface to bedrock ice cores, we used an Analytical Spectral Devices (ASD) FieldSpec4 Standard Resolution spectroradiometer to measure incoming solar radiation, outgoing surface reflectance and optical grain size on the Kahiltna Glacier and at the Kahiltna Base Camp. A Campbell Scientific automatic weather station was installed on Mount Hunter (3900m) in June 2013, complementing a longer-term (2008-present) station installed at Kahiltna Base Camp (2100m). Use of our in situ data aids in the validation of surface albedo values derived from Moderate Resolution Imaging Spectroradiometer (MODIS) and Landsat satellite imagery. Comparisons are made between ASD FieldSpec4 ground measurements and 500m MODIS imagery to assess the ability of MODIS to capture the variability of surface albedo across the glacier surface. The MODIS MCD43A3 BRDF/Albedo Product performs well at Kahiltna Base Camp (albedo (10-28% relative to ASD data) appear to occur along the Kahiltna Glacier due to the snow-free valley walls being captured in the 500m MODIS footprint. Incorporating Landsat imagery will strengthen our interpretations and has the potential to produce a long-term (1982-present) validated satellite albedo record for steep and mountainous terrain. Once validation is complete, we will compare the satellite-derived albedo record to the Denali ice core accumulation rate, aerosol records (i.e. volcanics and biomass burning), and glacier mass balance data. This research will ultimately contribute to an improved understanding of the

  9. Regionalization Study of Satellite based Hydrological Model (SHM) in Hydrologically Homogeneous River Basins of India

    Science.gov (United States)

    Kumari, Babita; Paul, Pranesh Kumar; Singh, Rajendra; Mishra, Ashok; Gupta, Praveen Kumar; Singh, Raghvendra P.

    2017-04-01

    A new semi-distributed conceptual hydrological model, namely Satellite based Hydrological Model (SHM), has been developed under 'PRACRITI-2' program of Space Application Centre (SAC), Ahmedabad for sustainable water resources management of India by using data from Indian Remote Sensing satellites. Entire India is divided into 5km x 5km grid cells and properties at the center of the cells are assumed to represent the property of the cells. SHM contains five modules namely surface water, forest, snow, groundwater and routing. Two empirical equations (SCS-CN and Hargreaves) and water balance method have been used in the surface water module; the forest module is based on the calculations of water balancing & dynamics of subsurface. 2-D Boussinesq equation is used for groundwater modelling which is solved using implicit finite-difference. The routing module follows a distributed routing approach which requires flow path and network with the key point of travel time estimation. The aim of this study is to evaluate the performance of SHM using regionalization technique which also checks the usefulness of a model in data scarce condition or for ungauged basins. However, homogeneity analysis is pre-requisite to regionalization. Similarity index (Φ) and hierarchical agglomerative cluster analysis are adopted to test the homogeneity in terms of physical attributes of three basins namely Brahmani (39,033 km km^2)), Baitarani (10,982 km km^2)) and Kangsabati (9,660 km km^2)) with respect to Subarnarekha (29,196 km km^2)) basin. The results of both homogeneity analysis show that Brahmani basin is the most homogeneous with respect to Subarnarekha river basin in terms of physical characteristics (land use land cover classes, soiltype and elevation). The calibration and validation of model parameters of Brahmani basin is in progress which are to be transferred into the SHM set up of Subarnarekha basin and results are to be compared with the results of calibrated and validated

  10. Paleoseismic study of the Cathedral Rapids fault in the northern Alaska Range near Tok, Alaska

    Science.gov (United States)

    Koehler, R. D.; Farrell, R.; Carver, G. A.

    2010-12-01

    The Cathedral Rapids fault extends ~40 km between the Tok and Robertson River valleys and is the easternmost fault in a series of active south-dipping imbricate thrust faults which bound the northern flank of the Alaska Range. Collectively, these faults accommodate a component of convergence transferred north of the Denali fault and related to the westward (counterclockwise) rotation of the Wrangell Block driven by relative Pacific/North American plate motion along the eastern Aleutian subduction zone and Fairweather fault system. To the west, the system has been defined as the Northern Foothills Fold and Thrust Belt (NFFTB), a 50-km-wide zone of east-west trending thrust faults that displace Quaternary deposits and have accommodated ~3 mm/yr of shortening since latest Pliocene time (Bemis, 2004). Over the last several years, the eastward extension of the NFFTB between Delta Junction and the Canadian border has been studied by the Alaska Division of Geological & Geophysical Surveys to better characterize faults that may affect engineering design of the proposed Alaska-Canada natural gas pipeline and other infrastructure. We summarize herein reconnaissance field observations along the western part of the Cathedral Rapids fault. The western part of the Cathedral Rapids fault extends 21 km from Sheep Creek to Moon Lake and is characterized by three roughly parallel sinuous traces that offset glacial deposits of the Illinoian to early Wisconsinan Delta glaciations and the late Wisconsinan Donnelly glaciation, as well as, Holocene alluvial deposits. The northern trace of the fault is characterized by an oversteepened, beveled, ~2.5-m-high scarp that obliquely cuts a Holocene alluvial fan and projects into the rangefront. Previous paleoseismic studies along the eastern part of the Cathedral Rapids fault and Dot “T” Johnson fault indicate multiple latest Pleistocene and Holocene earthquakes associated with anticlinal folding and thrust faulting (Carver et al., 2010

  11. Simulation of Regional Ground-Water Flow in the Suwannee River Basin, Northern Florida and Southern Georgia

    Science.gov (United States)

    Planert, Michael

    2007-01-01

    The Suwannee River Basin covers a total of nearly 9,950 square miles in north-central Florida and southern Georgia. In Florida, the Suwannee River Basin accounts for 4,250 square miles of north-central Florida. Evaluating the impacts of increased development in the Suwannee River Basin requires a quantitative understanding of the boundary conditions, hydrogeologic framework and hydraulic properties of the Floridan aquifer system, and the dynamics of water exchanges between the Suwannee River and its tributaries and the Floridan aquifer system. Major rivers within the Suwannee River Basin are the Suwannee, Santa Fe, Alapaha, and Withlacoochee. Four rivers west of the Suwannee River are the Aucilla, the Econfina, the Fenholloway, and the Steinhatchee; all drain to the Gulf of Mexico. Perhaps the most notable aspect of the surface-water hydrology of the study area is that large areas east of the Suwannee River are devoid of channelized, surface drainage; consequently, most of the drainage occurs through the subsurface. The ground-water flow system underlying the study area plays a critical role in the overall hydrology of this region of Florida because of the dominance of subsurface drain-age, and because ground-water flow sustains the flow of the rivers and springs. Three principal hydrogeologic units are present in the study area: the surficial aquifer system, the intermediate aquifer system, and the Floridan aquifer system. The surficial aquifer system principally consists of unconsoli-dated to poorly indurated siliciclastic deposits. The intermediate aquifer system, which contains the intermediate confining unit, lies below the surficial aquifer system (where present), and generally consists of fine-grained, uncon-solidated deposits of quartz sand, silt, and clay with interbedded limestone of Miocene age. Regionally, the intermediate aquifer system and intermediate con-fining unit act as a confining unit that restricts the exchange of water between the over

  12. Influence of land cover on riverine dissolved organic carbon concentrations and export in the Three Rivers Headwater Region of the Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Ma, Xiaoliang; Liu, Guimin; Wu, Xiaodong; Smoak, Joseph M; Ye, Linlin; Xu, Haiyan; Zhao, Lin; Ding, Yongjian

    2018-07-15

    The Qinghai-Tibetan plateau (QTP) stores a large amount of soil organic carbon and is the headwater region for several large rivers in Asia. Therefore, it is important to understand the influence of environmental factors on river water quality and the dissolved organic carbon (DOC) export in this region. We examined the water physico-chemical characteristics, DOC concentrations and export rates of 7 rivers under typical land cover types in the Three Rivers Headwater Region during August 2016. The results showed that the highest DOC concentrations were recorded in the rivers within the catchment of alpine wet meadow and meadow. These same rivers had the lowest total suspended solids (TSS) concentrations. The rivers within steppe and desert had the lowest DOC concentrations and highest TSS concentrations. The discharge rates and catchment areas were negatively correlated with DOC concentrations. The SUVA 254 values were significantly negatively correlated with DOC concentrations. The results suggest that the vegetation degradation, which may represent permafrost degradation, can lead to a decrease in DOC concentration, but increasing DOC export and soil erosion. In addition, some of the exported DOC will rapidly decompose in the river, and therefore affect the regional carbon cycle, as well as the water quality in the source water of many large Asian rivers. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Modelling and Analysis of Hydrodynamics and Water Quality for Rivers in the Northern Cold Region of China.

    Science.gov (United States)

    Tang, Gula; Zhu, Yunqiang; Wu, Guozheng; Li, Jing; Li, Zhao-Liang; Sun, Jiulin

    2016-04-08

    In this study, the Mudan River, which is the most typical river in the northern cold region of China was selected as the research object; Environmental Fluid Dynamics Code (EFDC) was adopted to construct a new two-dimensional water quality model for the urban sections of the Mudan River, and concentrations of COD(Cr) and NH₃N during ice-covered and open-water periods were simulated and analyzed. Results indicated that roughness coefficient and comprehensive pollutant decay rate were significantly different in those periods. To be specific, the roughness coefficient in the ice-covered period was larger than that of the open-water period, while the decay rate within the former period was smaller than that in the latter. In addition, according to the analysis of the simulated results, the main reasons for the decay rate reduction during the ice-covered period are temperature drop, upstream inflow decrease and ice layer cover; among them, ice sheet is the major contributor of roughness increase. These aspects were discussed in more detail in this work. The model could be generalized to hydrodynamic water quality process simulation researches on rivers in other cold regions as well.

  14. Modelling and Analysis of Hydrodynamics and Water Quality for Rivers in the Northern Cold Region of China

    Directory of Open Access Journals (Sweden)

    Gula Tang

    2016-04-01

    Full Text Available In this study, the Mudan River, which is the most typical river in the northern cold region of China was selected as the research object; Environmental Fluid Dynamics Code (EFDC was adopted to construct a new two-dimensional water quality model for the urban sections of the Mudan River, and concentrations of CODCr and NH3N during ice-covered and open-water periods were simulated and analyzed. Results indicated that roughness coefficient and comprehensive pollutant decay rate were significantly different in those periods. To be specific, the roughness coefficient in the ice-covered period was larger than that of the open-water period, while the decay rate within the former period was smaller than that in the latter. In addition, according to the analysis of the simulated results, the main reasons for the decay rate reduction during the ice-covered period are temperature drop, upstream inflow decrease and ice layer cover; among them, ice sheet is the major contributor of roughness increase. These aspects were discussed in more detail in this work. The model could be generalized to hydrodynamic water quality process simulation researches on rivers in other cold regions as well.

  15. Centennial- to decadal-scale monsoon precipitation variations in the upper Hanjiang River region, China over the past 6650 years

    Science.gov (United States)

    Tan, Liangcheng; Cai, Yanjun; Cheng, Hai; Edwards, Lawrence R.; Gao, Yongli; Xu, Hai; Zhang, Haiwei; An, Zhisheng

    2018-01-01

    The upper Hanjiang River region is the recharge area of the middle route of South-to-North Water Transfer Project. The region is under construction of the Hanjiang-Weihe River Water Transfer Project in China. Monsoon precipitation variations in this region are critical to water resource and security of China. In this study, high-resolution monsoon precipitation variations were reconstructed in the upper Hanjiang River region over the past 6650 years from δ18O and δ13C records of four stalagmites in Xianglong cave. The long term increasing trend of stalagmite δ18O record since the middle Holocene is consistent with other speleothem records from monsoonal China. This trend follows the gradually decreasing Northern Hemisphere summer insolation, which indicates that solar insolation may control the orbital-scale East Asian summer monsoon (EASM) variations. Despite the declined EASM intensity since the middle Holocene, local precipitation may not have decreased remarkably, as revealed by the δ13C records. A series of centennial- to decadal-scale cyclicity was observed, with quasi-millennium-, quasi-century-, 57-, 36- and 22-year cycles by removing the long-term trend of stalagmite δ18O record. Increased monsoon precipitation during periods of 4390-3800 a BP, 3590-2960 a BP, 2050-1670 a BP and 1110-790 a BP had caused four super-floods in the upper reach of Hanjiang River. Dramatically dry climate existed in this region during the 5.0 ka and 2.8 ka events, coinciding with notable droughts in other regions of monsoonal China. Remarkably intensified and southward Westerly jet, together with weakened summer monsoon, may delay the onset of rainy seasons, resulting in synchronous decreasing of monsoon precipitation in China during the two events. During the 4.2 ka event and the Little Ice Age, the upper Hanjiang River region was wet, which was similar to the climate conditions in central and southern China, but was the opposite of drought observed in northern China. We

  16. Simulation of regional-scale groundwater flow in the Azul River basin, Buenos Aires Province, Argentina

    Science.gov (United States)

    Varni, Marcelo R.; Usunoff, Eduardo J.

    A three-dimensional modular model (MODFLOW) was used to simulate groundwater flow in the Azul River basin, Buenos Aires Province, Argentina, in order to assess the correctness of the conceptual model of the hydrogeological system. Simulated heads satisfactorily match observed heads in the regional water-table aquifer. Model results indicate that: (1) groundwater recharge is not uniform throughout the region but is best represented by three recharge rates, decreasing downgradient, similar to the distribution of soils and geomorphological characteristics; and (2) evapotranspiration rates are larger than previous estimates, which were made by using the Thornthwaite-Mather method. Evapotranspiration rates estimated by MODFLOW agree with results of independent studies of the region. Model results closely match historical surface-flow records, thereby suggesting that the model description of the aquifer-river relationship is correct. Résumé Un modèle modulaire tridimensionnel (MODFLOW) a été utilisé pour simuler les écoulements souterrains dans le bassin de la rivière Azul (Province de Buenos Aires, Argentine), dans le but d'évaluer la justesse du modèle conceptuel du système hydrogéologique. La piézométrie simulée s'ajuste de façon satisfaisante à celle observée pour l'ensemble de la nappe. Les résultats du modèle indiquent que: (1) la recharge de la nappe n'est pas uniforme sur toute la région, mais qu'elle est mieux approchée par trois valeurs différentes, décroissant vers l'aval-gradient, en suivant la même distribution que les sols et les caractéristiques géomorphologiques et (2) l'évapotranspiration est nettement plus importante que prévu initialement à partir de la méthode de Thornthwaite-Mather. Les valeurs d'évapotranspiration fournies par MODFLOW concordent bien avec les résultats d'autres études portant sur la région. Les résultats du modèle reproduisent convenablement les chroniques de débit des écoulements de surface

  17. When local extinction and colonization of river fishes can be predicted by regional occupancy: the role of spatial scales.

    Directory of Open Access Journals (Sweden)

    Benjamin Bergerot

    Full Text Available Predicting which species are likely to go extinct is perhaps one of the most fundamental yet challenging tasks for conservation biologists. This is particularly relevant for freshwater ecosystems which tend to have the highest proportion of species threatened with extinction. According to metapopulation theories, local extinction and colonization rates of freshwater subpopulations can depend on the degree of regional occupancy, notably due to rescue effects. However, relationships between extinction, colonization, regional occupancy and the spatial scales at which they operate are currently poorly known.And Findings: We used a large dataset of freshwater fish annual censuses in 325 stream reaches to analyse how annual extinction/colonization rates of subpopulations depend on the regional occupancy of species. For this purpose, we modelled the regional occupancy of 34 fish species over the whole French river network and we tested how extinction/colonization rates could be predicted by regional occupancy described at five nested spatial scales. Results show that extinction and colonization rates depend on regional occupancy, revealing existence a rescue effect. We also find that these effects are scale dependent and their absolute contribution to colonization and extinction tends to decrease from river section to larger basin scales.In terms of management, we show that regional occupancy quantification allows the evaluation of local species extinction/colonization dynamics and reduction of local extinction risks for freshwater fish species implies the preservation of suitable habitats at both local and drainage basin scales.

  18. When local extinction and colonization of river fishes can be predicted by regional occupancy: the role of spatial scales.

    Science.gov (United States)

    Bergerot, Benjamin; Hugueny, Bernard; Belliard, Jérôme

    2013-01-01

    Predicting which species are likely to go extinct is perhaps one of the most fundamental yet challenging tasks for conservation biologists. This is particularly relevant for freshwater ecosystems which tend to have the highest proportion of species threatened with extinction. According to metapopulation theories, local extinction and colonization rates of freshwater subpopulations can depend on the degree of regional occupancy, notably due to rescue effects. However, relationships between extinction, colonization, regional occupancy and the spatial scales at which they operate are currently poorly known. And Findings: We used a large dataset of freshwater fish annual censuses in 325 stream reaches to analyse how annual extinction/colonization rates of subpopulations depend on the regional occupancy of species. For this purpose, we modelled the regional occupancy of 34 fish species over the whole French river network and we tested how extinction/colonization rates could be predicted by regional occupancy described at five nested spatial scales. Results show that extinction and colonization rates depend on regional occupancy, revealing existence a rescue effect. We also find that these effects are scale dependent and their absolute contribution to colonization and extinction tends to decrease from river section to larger basin scales. In terms of management, we show that regional occupancy quantification allows the evaluation of local species extinction/colonization dynamics and reduction of local extinction risks for freshwater fish species implies the preservation of suitable habitats at both local and drainage basin scales.

  19. Non-methane hydrocarbon characteristics of motor vehicular emissions in the Pearl River Delta region

    Science.gov (United States)

    Tsai, Wai Yan

    2007-12-01

    Air pollution problem in Hong Kong and the Pearl River Delta (PRD) region has raised much concern from the public in recent years. The primary aim of this research is to use field measurement data to characterize non-methane hydrocarbons (NMHCs) in emission from motor vehicles. Fuel vapor compositions for several commonly used vehicular fuels in Hong Kong, Macau, Guangzhou and Zhuhai were analyzed in 2003, and they are believed to be the first one reported for the PRD region. These profiles were used to study the impact of evaporative loss of the fuels on air quality. From the roadside and tunnel samples collected in the four cities mentioned above from 2000 to 2003, results showed that vehicular engine combustion was a main NMHC source, while gasoline evaporative losses also contributed much to the total NMHC emission, besides, LPG leakage was also found to be significant from the tunnel measurement data collected in Hong Kong. Characteristics of vehicular engine exhaust emissions were also studied. Measurements of diesel emission showed a large influence on the emission profile due to the change of diesel compositions. The E/E ratios implied that gasoline-powered vehicles in Hong Kong were equipped with well functioning catalysts, while those in Guangzhou and Zhuhai, especially the motorcycles, were found dirtier in NMHC emission. Although the E/E ratios showed that private cars in Hong Kong had high combustion efficiency, the existence of significant amounts of unburned gasoline in their exhaust stream pointed out that they still had low fuel economy. From the results of a simple model, it was found that the evaporative losses of gasoline and LPG contributed much to the total NMHC pollution from vehicle. The preliminary results from the dynamometer study conducted in Hong Kong showed large variations of exhaust characteristics for private cars and taxis during different driving speeds. The results can be used as scientific basis for regulatory parties in

  20. Regional economic analysis of current and proposed management alternatives for Rappahannock River Valley National Wildlife Refuge

    Science.gov (United States)

    Koontz, Lynne; Sexton, Natalie; Donovan, Ryan

    2009-01-01

    The National Wildlife Refuge System Improvement Act of 1997 requires all units of the National Wildlife Refuge System to be managed under a Comprehensive Conservation Plan. The Comprehensive Conservation Plan must describe the desired future conditions of a refuge and provide long-range guidance and management direction to achieve refuge purposes. The Rappahannock River Valley National Wildlife Refuge (refuge) is in the process of developing a range of management goals, objectives, and strategies for the Comprehensive Conservation Plan. The Comprehensive Conservation Plan for the refuge must contain an analysis of expected effects associated with current and proposed refuge management strategies. The purpose of this study was to assess the regional economic implications associated with draft Comprehensive Conservation Plan management strategies. Special interest groups and local residents often criticize a change in refuge management, especially if there is a perceived negative impact to the local economy. Having objective data on economic impacts may show that these fears are overstated. Quite often, the extent of economic benefits a refuge provides to a local community is not fully recognized, yet at the same time the effects of negative changes is overstated. Spending associated with refuge recreational activities, such as wildlife viewing and hunting, can generate considerable tourist activity for surrounding communities. Additionally, refuge personnel typically spend considerable amounts of money purchasing supplies in local stores, repairing equipment and purchasing fuel at the local service stations, and reside and spend their salaries in the local community. For refuge Comprehensive Conservation Plan planning, a regional economic assessment provides a means of estimating how current management (no action alternative) and proposed management activities (alternatives) could affect the local economy. This type of analysis provides two critical pieces of

  1. Ecosystem Carbon Emissions from 2015 Forest Fires in Interior Alaska

    Science.gov (United States)

    Potter, Christopher S.

    2018-01-01

    In the summer of 2015, hundreds of wildfires burned across the state of Alaska, and consumed more than 1.6 million ha of boreal forest and wetlands in the Yukon-Koyukuk region. Mapping of 113 large wildfires using Landsat satellite images from before and after 2015 indicated that nearly 60% of this area was burned at moderate-to-high severity levels. Field measurements near the town of Tanana on the Yukon River were carried out in July of 2017 in both unburned and 2015 burned forested areas (nearly adjacent to one-another) to visually verify locations of different Landsat burn severity classes (low, moderate, or high). Results: Field measurements indicated that the loss of surface organic layers in boreal ecosystem fires is a major factor determining post-fire soil temperature changes, depth of thawing, and carbon losses from the mineral topsoil layer. Measurements in forest sites showed that soil temperature profiles to 30 cm depth at burned forest sites increased by an average of 8o - 10o C compared to unburned forest sites. Sampling and laboratory analysis indicated a 65% reduction in soil carbon content and a 58% reduction in soil nitrogen content in severely burned sample sites compared to soil mineral samples from nearby unburned spruce forests. Conclusions: Combined with nearly unprecedented forest areas severely burned in the Interior region of Alaska in 2015, total ecosystem fire emission of carbon to the atmosphere exceeded most previous estimates for the state.

  2. Hydrologic Conditions that Influence Streamflow Losses in a Karst Region of the Upper Peace River, Polk County, Florida

    Science.gov (United States)

    Metz, P.A.; Lewelling, B.R.

    2009-01-01

    The upper Peace River from Bartow to Fort Meade, Florida, is described as a groundwater recharge area, reflecting a reversal from historical groundwater discharge patterns that existed prior to the 1950s. The upper Peace River channel and floodplain are characterized by extensive karst development, with numerous fractures, crevasses, and sinks that have been eroded in the near-surface and underlying carbonate bedrock. With the reversal in groundwater head gradients, river water is lost to the underlying groundwater system through these karst features. An investigation was conducted to evaluate the hydrologic conditions that influence streamflow losses in the karst region of the upper Peace River. The upper Peace River is located in a basin that has been altered substantially by phosphate mining and increases in groundwater use. These alterations have changed groundwater flow patterns and caused streamflow declines through time. Hydrologic factors that have had the greatest influence on streamflow declines in the upper Peace River include the lowering of the potentiometric surfaces of the intermediate aquifer system and Upper Floridan aquifer beneath the riverbed elevation due to below-average rainfall (droughts), increases in groundwater use, and the presence of numerous karst features in the low-water channel and floodplain that enhance the loss of streamflow. Seepage runs conducted along the upper Peace River, from Bartow to Fort Meade, indicate that the greatest streamflow losses occurred along an approximate 2-mile section of the river beginning about 1 mile south of the Peace River at Bartow gaging station. Along the low-water and floodplain channel of this 2-mile section, there are about 10 prominent karst features that influence streamflow losses. Losses from the individual karst features ranged from 0.22 to 16 cubic feet per second based on measurements made between 2002 and 2007. The largest measured flow loss for all the karst features was about 50 cubic

  3. Characterizing and modelling river channel migration rates at a regional scale: Case study of south-east France.

    Science.gov (United States)

    Alber, Adrien; Piégay, Hervé

    2017-11-01

    An increased awareness by river managers of the importance of river channel migration to sediment dynamics, habitat complexity and other ecosystem functions has led to an advance in the science and practice of identifying, protecting or restoring specific erodible corridors across which rivers are free to migrate. One current challenge is the application of these watershed-specific goals at the regional planning scales (e.g., the European Water Framework Directive). This study provides a GIS-based spatial analysis of the channel migration rates at the regional-scale. As a case study, 99 reaches were sampled in the French part of the Rhône Basin and nearby tributaries of the Mediterranean Sea (111,300 km 2 ). We explored the spatial correlation between the channel migration rate and a set of simple variables (e.g., watershed area, channel slope, stream power, active channel width). We found that the spatial variability of the channel migration rates was primary explained by the gross stream power (R 2  = 0.48) and more surprisingly by the active channel width scaled by the watershed area. The relationship between the absolute migration rate and the gross stream power is generally consistent with the published empirical models for freely meandering rivers, whereas it is less significant for the multi-thread reaches. The discussion focused on methodological constraints for a regional-scale modelling of the migration rates, and the interpretation of the empirical models. We hypothesize that the active channel width scaled by the watershed area is a surrogate for the sediment supply which may be a more critical factor than the bank resistance for explaining the regional-scale variability of the migration rates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Geomorphological assessment of sites and impoundments for the long term containment of uranium mill tailings in the Alligator Rivers Region

    International Nuclear Information System (INIS)

    East, T.J.

    1986-01-01

    This paper presents a program of current and future research into those geomorphological processes likely to affect the long term containment of uranium mill tailings in the Alligator Rivers Region of the Northern Territory. Research is directed at three main areas: identification of geomorphic hazards at proposed impoundment sites; determination of erosion rates on impoundment slopes; and prediction of patterns of fluvial dispersal of released tailings. Each necessitates consideration of present and future geomorphic processes

  5. Alaska volcanoes guidebook for teachers

    Science.gov (United States)

    Adleman, Jennifer N.

    2011-01-01

    Alaska’s volcanoes, like its abundant glaciers, charismatic wildlife, and wild expanses inspire and ignite scientific curiosity and generate an ever-growing source of questions for students in Alaska and throughout the world. Alaska is home to more than 140 volcanoes, which have been active over the last 2 million years. About 90 of these volcanoes have been active within the last 10,000 years and more than 50 of these have been active since about 1700. The volcanoes in Alaska make up well over three-quarters of volcanoes in the United States that have erupted in the last 200 years. In fact, Alaska’s volcanoes erupt so frequently that it is almost guaranteed that an Alaskan will experience a volcanic eruption in his or her lifetime, and it is likely they will experience more than one. It is hard to imagine a better place for students to explore active volcanism and to understand volcanic hazards, phenomena, and global impacts. Previously developed teachers’ guidebooks with an emphasis on the volcanoes in Hawaii Volcanoes National Park (Mattox, 1994) and Mount Rainier National Park in the Cascade Range (Driedger and others, 2005) provide place-based resources and activities for use in other volcanic regions in the United States. Along the lines of this tradition, this guidebook serves to provide locally relevant and useful resources and activities for the exploration of numerous and truly unique volcanic landscapes in Alaska. This guidebook provides supplemental teaching materials to be used by Alaskan students who will be inspired to become educated and prepared for inevitable future volcanic activity in Alaska. The lessons and activities in this guidebook are meant to supplement and enhance existing science content already being taught in grade levels 6–12. Correlations with Alaska State Science Standards and Grade Level Expectations adopted by the Alaska State Department of Education and Early Development (2006) for grades six through eleven are listed at

  6. Heavy Metal Pollution in a Soil-Rice System in the Yangtze River Region of China.

    Science.gov (United States)

    Liu, Zhouping; Zhang, Qiaofen; Han, Tiqian; Ding, Yanfei; Sun, Junwei; Wang, Feijuan; Zhu, Cheng

    2015-12-22

    Heavy metals are regarded as toxic trace elements in the environment. Heavy metal pollution in soil or rice grains is of increasing concern. In this study, 101 pairs of soil and rice samples were collected from the major rice-producing areas along the Yangtze River in China. The soil properties and heavy metal (i.e., Cd, Hg, Pb and Cr) concentrations in the soil and rice grains were analyzed to evaluate the heavy metal accumulation characteristics of the soil-rice systems. The results showed that the Cd, Hg, Pb and Cr concentrations in the soil ranged from 0.10 to 4.64, 0.01 to 1.46, 7.64 to 127.56, and 13.52 to 231.02 mg·kg(-)¹, respectively. Approximately 37%, 16%, 60% and 70% of the rice grain samples were polluted by Cd, Hg, Pb, and Cr, respectively. The degree of heavy metal contamination in the soil-rice systems exhibited a regional variation. The interactions among the heavy metal elements may also influence the migration and accumulation of heavy metals in soil or paddy rice. The accumulation of heavy metals in soil and rice grains is related to a certain extent to the pH and soil organic matter (SOM). This study provides useful information regarding heavy metal accumulation in soil to support the safe production of rice in China. The findings from this study also provide a robust scientific basis for risk assessments regarding ecological protection and food safety.

  7. Sources and characteristics of carbonaceous aerosol in two largest cities in Pearl River Delta Region, China

    Science.gov (United States)

    Duan, Jingchun; Tan, Jihua; Cheng, Dingxi; Bi, Xinhui; Deng, Wenjing; Sheng, Guoying; Fu, Jiamo; Wong, M. H.

    PM 2.5 samples were collected at five sites in Guangzhou and Hong Kong, Pearl River Delta Region (PRDR), China in both summer and winter during 2004-2005. Elemental carbon (EC) and organic carbon (OC) in these samples were measured. The OC and EC concentrations ranked in the order of urban Guangzhou > urban Hong Kong > background Hong Kong. Total carbonaceous aerosol (TCA) contributed less to PM 2.5 in urban Guangzhou (32-35%) than that in urban Hong Kong (43-57%). The reason may be that, as an major industrial city in South China, Guangzhou would receive large amount of inorganic aerosol from all kinds of industries, however, as a trade center and seaport, urban Hong Kong would mainly receive organic aerosol and EC from container vessels and heavy-duty diesel trucks. At Hong Kong background site Hok Tsui, relatively lower contribution of TCA to PM 2.5 may result from contributions of marine inorganic aerosol and inland China pollutant. Strong correlation ( R2=0.76-0.83) between OC and EC indicates minor fluctuation of emission and the secondary organic aerosol (SOA) formation in urban Guangzhou. Weak correlation between OC and EC in Hong Kong can be related to the impact of the long-range transported aerosol from inland China. Averagely, secondary OC (SOC) concentrations were 3.8-5.9 and 10.2-12.8 μg m -3, respectively, accounting for 21-32% and 36-42% of OC in summer and winter in Guangzhou. The average values of 4.2-6.8% for SOA/ PM 2.5 indicate that SOA was minor component in PM 2.5 in Guangzhou.

  8. Heavy Metal Pollution in a Soil-Rice System in the Yangtze River Region of China

    Directory of Open Access Journals (Sweden)

    Zhouping Liu

    2015-12-01

    Full Text Available Heavy metals are regarded as toxic trace elements in the environment. Heavy metal pollution in soil or rice grains is of increasing concern. In this study, 101 pairs of soil and rice samples were collected from the major rice-producing areas along the Yangtze River in China. The soil properties and heavy metal (i.e., Cd, Hg, Pb and Cr concentrations in the soil and rice grains were analyzed to evaluate the heavy metal accumulation characteristics of the soil-rice systems. The results showed that the Cd, Hg, Pb and Cr concentrations in the soil ranged from 0.10 to 4.64, 0.01 to 1.46, 7.64 to 127.56, and 13.52 to 231.02 mg·kg−1, respectively. Approximately 37%, 16%, 60% and 70% of the rice grain samples were polluted by Cd, Hg, Pb, and Cr, respectively. The degree of heavy metal contamination in the soil-rice systems exhibited a regional variation. The interactions among the heavy metal elements may also influence the migration and accumulation of heavy metals in soil or paddy rice. The accumulation of heavy metals in soil and rice grains is related to a certain extent to the pH and soil organic matter (SOM. This study provides useful information regarding heavy metal accumulation in soil to support the safe production of rice in China. The findings from this study also provide a robust scientific basis for risk assessments regarding ecological protection and food safety.

  9. Pollen flow of wheat under natural conditions in the Huanghuai River Wheat Region, China

    Science.gov (United States)

    Sun, Ai-Qing; Zhang, Chun-Qing; Wu, Cheng-Lai; Gao, Qing-Rong

    2015-01-01

    abstract The transgenic pollen spread is the main pathway of transgenic plant gene flow. The maximum distance of pollen dispersal (horizontal), the spatial dynamics of pollen movement (vertical), and the patterns of pollen dispersal are important considerations in biosafety assessments of genetically modified crops. To evaluate wheat (Triticum aestivum) pollen dispersal, we measured the pollen suspension velocity and analyzed pollen dispersal patterns under natural conditions in the Huanghuai River wheat-growing region in 2009. The pollen suspension velocity was 0.3–0.4 m/s. The highest pollen densities were detected in the north, northwest, and south of the pollen source. Pollen was dispersed over distances greater than 245 m in the northwest and northeast directions. At the pollen source center, pollen density decreased with increasing vertical height. In the north of the pollen source, the pollen density from 65 m to 225 m showed a wave-mode decrease with increasing height. The horizontal transport of pollen over longer distances fitted polynomial equations. In the north, the pollen density was highest at 45 m from the pollen source, and decreased with increasing distance. In the northwest, the pollen density showed a double-peak trend. In the northeast, pollen density was highest from 45 m to 125 m from the source. Wind speeds greater than the pollen suspension velocity and the duration of continuous gusts were the main factors affecting pollen dispersal. This information will be useful for determining the spatial isolation distances for hybrid seed production and for the commercial production of transgenic wheat. PMID:25658025

  10. Heavy Metal Pollution in a Soil-Rice System in the Yangtze River Region of China

    Science.gov (United States)

    Liu, Zhouping; Zhang, Qiaofen; Han, Tiqian; Ding, Yanfei; Sun, Junwei; Wang, Feijuan; Zhu, Cheng

    2015-01-01

    Heavy metals are regarded as toxic trace elements in the environment. Heavy metal pollution in soil or rice grains is of increasing concern. In this study, 101 pairs of soil and rice samples were collected from the major rice-producing areas along the Yangtze River in China. The soil properties and heavy metal (i.e., Cd, Hg, Pb and Cr) concentrations in the soil and rice grains were analyzed to evaluate the heavy metal accumulation characteristics of the soil-rice systems. The results showed that the Cd, Hg, Pb and Cr concentrations in the soil ranged from 0.10 to 4.64, 0.01 to 1.46, 7.64 to 127.56, and 13.52 to 231.02 mg·kg−1, respectively. Approximately 37%, 16%, 60% and 70% of the rice grain samples were polluted by Cd, Hg, Pb, and Cr, respectively. The degree of heavy metal contamination in the soil-rice systems exhibited a regional variation. The interactions among the heavy metal elements may also influence the migration and accumulation of heavy metals in soil or paddy rice. The accumulation of heavy metals in soil and rice grains is related to a certain extent to the pH and soil organic matter (SOM). This study provides useful information regarding heavy metal accumulation in soil to support the safe production of rice in China. The findings from this study also provide a robust scientific basis for risk assessments regarding ecological protection and food safety. PMID:26703698

  11. Effects of the Changiang river discharge on the change in ocean and atmosphere over the East Asian region

    Science.gov (United States)

    Kim, M. H.; Lim, Y. J.; Kang, H. S.; Kim, B. J.; Cho, C.

    2017-12-01

    This study investigates the effects of freshwater from the Changiang river basin over the East Asian region for summer season. To do this, we simulated global seasonal forecasting system (GloSea5) of KMA (Korea Meteorology Administration). GloSea5 consists of atmosphere, ocean, sea ice and land model. Also, it has river routing model (TRIP), which links between land and ocean using freshwater. It is very important component in long-term forecast because of be able to change the air-sea interaction. To improve more the freshwater performance over the East Asian region, we realistically modified the river mouth, direction and storage around Changiang river basin of TRIP in GloSea5. Here, the comparison study among the no freshwater forcing experiment to ocean model (TRIP-OFF), the operated original file based freshwater coupled experiment (TRIP-ON) and the improved one (TRIP-MODI) has been carried out and the results are evaluated against the reanalysis data. As a result, the amount of fresh water to the Yellow Sea increase in TRIP-ON experiment and it attributes to the improvement of bias and RMSE of local SST over the East Asia. The implementation of the realistic river related ancillary files (TRIP-MODI) improves the abnormal salinity distribution around the Changjiang river gate and its related SST reduces cold bias about 0.37˚C for July over the East Sea. Warm SST over this region is caused by barrier layer (BL). Freshwater flux and salinity changes can create a pronounced salinity-induced mixed layer (ML) above the top of the thermocline. The layer between the base of the ML and the top of the thermocline is called a barrier layer (BL), because it isolates the warm surface water from cold deep water. In addition, the improved fresh water forcing can lead to the change in the local volume transport from the Kuroshio to the Strait of Korea and Changed the transport and SST over the Straits of Korea have correlation 0.57 at 95% confidence level. For the

  12. The parasite community of gobiid fishes (Actinopterygii: Gobiidae) from the Lower Volga River region

    Czech Academy of Sciences Publication Activity Database

    Kvach, Yuriy; Boldyrev, V.; Lohner, R.; Stepien, C. A.

    2015-01-01

    Roč. 70, č. 7 (2015), s. 948-957 ISSN 0006-3088 Institutional support: RVO:68081766 Keywords : Gobiidae * parasites * Volga River * Caspian Sea * introduced species Subject RIV: EG - Zoology Impact factor: 0.719, year: 2015

  13. Regional Sediment Analysis of Mississippi River Sediment Transport and Hydrographic Survey Data

    National Research Council Canada - National Science Library

    Thorne, Colin

    2002-01-01

    The cumulative impacts of human occupation and development of watersheds, combined with engineering works on river channels have significantly disrupted the dynamic equilibrium of many stream systems and ecosystem...

  14. Environmental Assessment for the construction and operation of the Three Rivers Solid Waste Authority regional waste management center at the Savannah River Site

    International Nuclear Information System (INIS)

    1995-12-01

    This Environmental Assessment (EA) has been prepared by the US Department of Energy (DOE) to assess the potential environmental impacts associated with the construction and operation of a landfill and technology center for regionally-generated municipal solid waste at the Savannah River Site (SRS) near Aiken, South Carolina. The facility would serve the municipal solid waste disposal needs for SRS and at least nine of the surrounding counties who currently comprise the Three Rivers Solid Waste Authority (TRSWA). Additional counties could become included in the proposed action at some future date. Current Federal and state requirements do not afford individual counties and municipalities within the region encompassing SRS the ability to efficiently or economically operate modern waste management facilities. In addition, consolidation of regional municipal solid waste at one location would have the benefit of reducing the duplicity of environmental consequences associated with the construction and operation of county-level facilities. The option to seek a combined disposal and technology development facility based on a regionally-cooperative effort was selected as a viable alternative to the existing individual SRS or county disposal activities. This document was prepared in compliance with the National Environmental Policy Act (NEPA) of 1969, as amended, the requirements of the Council on Environmental Quality Regulations for Implementing NEPA (40 CFR Part 1021). NEPA requires the assessment of environmental consequences of Federal actions that may affect the quality of the human environment. Based on the potential for impacts described for impacts described herein, DOE will either publish a Finding of No Significant Impact or prepare an environmental impact statement (EIS)

  15. Light Absorption of Brown Carbon Aerosol in the Pearl River Delta Region of China

    Science.gov (United States)

    Huang, X.

    2015-12-01

    X.F. Huang, J.F. Yuan, L.M. Cao, J. Cui, C.N. Huang, Z.J. Lan and L.Y. He Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, ChinaCorresponding author. Tel.: +86 755 26032532; fax: +86 755 26035332. E-mail address: huangxf@pku.edu.cn (X. F. Huang). Abstract: The strong spectral dependence of light absorption of brown carbon (BrC) aerosol has been recognized in recent decades. The Absorption Angstrom Exponent (AAE) of ambient aerosol was widely used in previous studies to attribute light absorption of brown carbon at shorter wavelengths, with a theoretical assumption that the AAE of black carbon (BC) aerosol equals to unit. In this study, the AAE method was improved by statistical extrapolation based on ambient measurements in the polluted seasons in typical urban and rural areas in the Pearl River Delta (PRD) region of China. A three-wavelength photoacoustic soot spectrometer (PASS-3) and an aerosol mass spectrometer (AMS) were used to explore the relationship between the ambient measured AAE and the ratio of organic aerosol to BC aerosol, in order to extract the more realistic AAE by pure BC aerosol, which were found to be 0.86, 0.82 and 1.02 at 405nm and 0.70, 0.71, and 0.86 at 532nm in the campaigns of urban-winter, urban-fall, and rural-fall, respectively. Roadway tunnel experiment results further supported the effectiveness of the obtained AAE for pure BC aerosol. In addition, biomass burning experiments proved higher spectral dependence of more-BrC environment and further verified the reliability of the instruments' response. Then, the average light absorption contribution of BrC aerosol was calculated to be 11.7, 6.3 and 12.1% (with total relative uncertainty of 7.5, 6.9 and 10.0%) at 405nm and 10.0, 4.1 and 5.5% (with total relative uncertainty of 6.5, 8.6 and 15.4%) at 532nm of the three campaigns, respectively. These results indicate that the

  16. Assessing regional climate simulations of the last 30 years (1982-2012) over Ganges-Brahmaputra-Meghna River Basin

    Science.gov (United States)

    Khandu; Awange, Joseph L.; Anyah, Richard; Kuhn, Michael; Fukuda, Yoichi

    2017-10-01

    The Ganges-Brahmaputra-Meghna (GBM) River Basin presents a spatially diverse hydrological regime due to it's complex topography and escalating demand for freshwater resources. This presents a big challenge in applying the current state-of-the-art regional climate models (RCMs) for climate change impact studies in the GBM River Basin. In this study, several RCM simulations generated by RegCM4.4 and PRECIS are assessed for their seasonal and interannual variations, onset/withdrawal of the Indian monsoon, and long-term trends in precipitation and temperature from 1982 to 2012. The results indicate that in general, RegCM4.4 and PRECIS simulations appear to reasonably reproduce the mean seasonal distribution of precipitation and temperature across the GBM River Basin, although the two RCMs are integrated over a different domain size. On average, the RegCM4.4 simulations overestimate monsoon precipitation by {˜ }26 and {˜ }5% in the Ganges and Brahmaputra-Meghna River Basin, respectively, while PRECIS simulations underestimate (overestimate) the same by {˜ }7% ({˜ }16%). Both RegCM4.4 and PRECIS simulations indicate an intense cold bias (up to 10° C) in the Himalayas, and are generally stronger in the RegCM4.4 simulations. Additionally, they tend to produce high precipitation between April and May in the Ganges (RegCM4.4 simulations) and Brahmaputra-Meghna (PRECIS simulations) River Basins, resulting in early onset of the Indian monsoon in the Ganges River Basin. PRECIS simulations exhibit a delayed monsoon withdrawal in the Brahmaputra-Meghna River Basin. Despite large spatial variations in onset and withdrawal periods across the GBM River Basin, the basin-averaged results agree reasonably well with the observed periods. Although global climate model (GCM) driven simulations are generally poor in representing the interannual variability of precipitation and winter temperature variations, they tend to agree well with observed precipitation anomalies when driven by

  17. Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska

    Science.gov (United States)

    Jones, B. M.; Tape, K. D.; Nitze, I.; Arp, C. D.; Grosse, G.; Zimmerman, C. E.

    2017-12-01

    Landscape-scale impacts of climate change in the Arctic include increases in growing season length, shrubby vegetation, winter river discharge, snowfall, summer and winter water temperatures, and decreases in river and lake ice thickness. Combined, these changes may have created conditions that are suitable for beaver colonization of low Arctic tundra regions. We developed a semi-automated workflow that analyzes Landsat imagery time series to determine the extent to which beavers may have colonized permafrost landscapes in arctic Alaska since 1999. We tested this approach on the Lower Noatak, Wulik, and Kivalina river watersheds in northwest Alaska and identified 83 locations representing potential beaver activity. Seventy locations indicated wetting trends and 13 indicated drying trends. Verification of each site using high-resolution satellite imagery showed that 80 % of the wetting locations represented beaver activity (damming and pond formation), 11 % were unrelated to beavers, and 9 % could not readily be distinguished as being beaver related or not. For the drying locations, 31 % represented beaver activity (pond drying due to dam abandonment), 62 % were unrelated to beavers, and 7 % were undetermined. Comparison of the beaver activity database with historic aerial photography from ca. 1950 and ca. 1980 indicates that beavers have recently colonized or recolonized riparian corridors in northwest Alaska. Remote sensing time series observations associated with the migration of beavers in permafrost landscapes in arctic Alaska include thermokarst lake expansion and drainage, thaw slump initiation, ice wedge degradation, thermokarst shore fen development, and possibly development of lake and river taliks. Additionally, beaver colonization in the Arctic may alter channel courses, thermal regimes, hyporheic flow, riparian vegetation, and winter ice regimes that could impact ecosystem structure and function in this region. In particular, the combination of beaver

  18. Environmental surveillance monitoring in the Alligator Rivers Region. Report for the six months period ending 30 September 1996

    International Nuclear Information System (INIS)

    1996-01-01

    This report outlines the activities of the Northern Territory Supervising Authorities in meeting their responsibilities for environmental management and surveillance, occupational safety, relating to uranium mining and environment protection in the Alligator Rivers Region. Environmental monitoring was carried out at the Nabarlek Mine, which site has now been rehabilitated and revegetated, and at Ranger, the only mine currently operating in the region. Other uranium projects such as Jabiluka and Koongarra have been delayed due to the former Commonwealth Government's 'three mines policy'. 4 tabs., 10 figs

  19. Regional development of river basins in the Olkiluoto-Pyhaejaervi Area, SW Finland, 2000 BP - 8000 AP

    International Nuclear Information System (INIS)

    Ojala, A.E.K.; Virkki, H.; Palmu, J.-P.; Hokkanen, K.; Kaija, J.

    2006-12-01

    Biosphere assessment forms one of the main components in Posiva's Safety Case portfolio and includes analyses of terrain and ecosystem development. Shoreline displacement and changes in surface hydrology form one part of these analyses. In this report, the regional development of the Olkiluoto-Pyhaejaervi area in the time period 2000 BP - 8000 AP was examined by taking into account changes in the surface flow patterns of the Lapinjoki and Eurajoki river basins. A hydrological model, EULA, was developed and applied to investigate the past and future hydrological regimes and changes in the Olkiluoto-Pyhaejaervi study area. As detailed assessment of erosion and sedimentation effects were not within the scope of this study, only their general effects were evaluated. The digital elevation models (DEM) for different time stages (2000, 1500, 1000 and 500 BP; 100, 300, 500, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500, 5000, 6000, 7000 and 8000 AP) were compiled taking into account the land uplift and tilting of the Earth's crust. With the aid of various sophisticated GIS tools, the boundaries of the main river basins, the flow patterns of rivers and development of lakes during each stage were modelled. The yearly discharge rates of rivers Eurajoki and Lapinjoki were also evaluated with the assumption that present climatic features prevail during the whole time period 2000 BP - 8000 AP. Finally, the probability of significant changes in the surface water flow routes were estimated during different stages. (orig.)

  20. Pasvik River Watercourse, Barents Region: Pollution Impacts and Ecological Responses. Investigations in 1993

    Energy Technology Data Exchange (ETDEWEB)

    Traaen, T; Moiseenko, T; Sandimirov, S and others

    1994-12-31

    The Pasvik River is one of the largest rivers in the Northern Fennoscandia and constitutes the border between Norway and Russia, with catchment area in Finland, Norway and Russia. Besides being strongly regulated for hydroelectric power production, the river is polluted by the smelter in Nikel and other industrial activities and by domestic sewage from the settlements on both sides of the border. This document discusses the pollution of the river and the ecological responses. The two main areas of concern are heavy metals and eutrophication. Very high content of heavy metals in water, lake sediments, macrophytes and fish was found in Kuetsyarvi. Extensive toxic effects were documented on the fish population in the lake. The toxic effects are less than expected from the concentration of heavy metals, which is due to high calcium content, organic matter and eutrophication. Eutrophication is due to the domestic sewage from settlements within the water catchment. Kuetsyarvi has eutrophic status, the lower parts of the Pasvik River have oligo-mesotrophic status according to phosphorus concentrations, and the composition of the planktonic and benthic communities. Because of increased and stabilized water level from hydroelectric power regulations, increased abundance of macrophytes and zoobenthos in shallow areas also have occurred. 77 refs., 32 figs., 28 tabs.

  1. Numerical model to quantify biogenic volatile organic compound emissions: The Pearl River Delta region as a case study.

    Science.gov (United States)

    Wang, Xuemei; Situ, Shuping; Chen, Weihua; Zheng, Junyu; Guenther, Alex; Fan, Qi; Chang, Ming

    2016-08-01

    This article compiles the actual knowledge of the biogenic volatile organic compound (BVOC) emissions estimated using model methods in the Pearl River Delta (PRD) region, one of the most developed regions in China. The developed history of BVOC emission models is presented briefly and three typical emission models are introduced and compared. The results from local studies related to BVOC emissions have been summarized. Based on this analysis, it is recommended that local researchers conduct BVOC emission studies systematically, from the assessment of model inputs, to compiling regional emission inventories to quantifying the uncertainties and evaluating the model results. Beyond that, more basic researches should be conducted in the future to close the gaps in knowledge on BVOC emission mechanisms, to develop the emission models and to refine the inventory results. This paper can provide a perspective on these aspects in the broad field of research associated with BVOC emissions in the PRD region. Copyright © 2016. Published by Elsevier B.V.

  2. River terrace development in the NE Mediterranean region (Syria and Turkey): Patterns in relation to crustal type

    Science.gov (United States)

    Bridgland, David R.; Demir, Tuncer; Seyrek, Ali; Daoud, Mohamad; Abou Romieh, Mohammad; Westaway, Rob

    2017-06-01

    It is widely recognized that the optimal development of river terraces globally has been in the temperate latitudes, with NW and Central Europe being areas of particular importance for the preservation of such archives of Quaternary environmental change. There is also a growing consensus that the principal drivers of terrace formation have been climatic fluctuation against a background of progressive (but variable) uplift. Nonetheless river terraces are widely preserved in the Mediterranean region, where they have often been attributed to the effects of neotectonic activity, with a continuing debate about the relative significance of fluctuating temperature (glacials-interglacials) and precipitation (pluvials-interpluvials). Research in Syria and southern-central Turkey (specifically in the valleys of the Tigris and Ceyhan in Turkey, the Kebir in Syria and the trans-border rivers Orontes and Euphrates) has underlined the importance of uplift rates in dictating the preservation pattern of fluvial archives and has revealed different patterns that can be related to crustal type. The NE Mediterranean coastal region has experienced unusually rapid uplift in the Late Quaternary. The relation between the Kebir terraces and the staircase of interglacial raised beaches preserved along the Mediterranean coastline of NW Syria reinforces previous conclusions that the emplacement of the fluvial terrace deposits in the Mediterranean has occurred during colder climatic episodes.

  3. Groundwater conservation and monitoring activities in the middle Brenta River plain (Veneto Region, Northern Italy: preliminary results about aquifer recharge

    Directory of Open Access Journals (Sweden)

    Andrea Sottani

    2014-09-01

    Full Text Available In the middle Brenta River plain there is a unconfined aquifer that represents an important groundwater resource in Veneto region. In this area the main groundwater recharge factor is related to the stream seepage: the water dispersion from the Brenta river is active with variable intensity from the foothill to the alignment Nove di Bassano - Cartigliano (Province of Vicenza. In order to mitigate the expected groundwater effects, due to future important waterworks withdrawals provided by the regional water resources management plans, an experimental project of Managed Aquifer Recharge has started, by means of the realization of some river transversal ramps. The construction of pilot works, partially completed, were preceded by a specific hydrogeological monitoring program, aimed to the evaluation of the effectiveness of the MAR actions in terms of comparison between pre-and post-operam conditions. Thanks to the development of a site-specific methodology, aimed to the quantification of the artificial infiltration rate, and after some years of monitoring controls of the hydrological and hydrogeological regimes, it is now possible to evaluate the extent and the rate of the recharge effects in groundwater due to ramps realization. The monitoring plan will be continued in the medium-long term. Some innovative approaches, based for example on the use of groundwater temperature measurements as recharge tracer, will help to validate the preliminary results.

  4. Water quality of the Chokosna, Gilahina, Lakina Rivers, and Long Lake watershed along McCarthy Road, Wrangell-St. Elias National Park and Preserve, Alaska, 2007-08

    Science.gov (United States)

    Brabets, Timothy P.; Ourso, Robert T.; Miller, Matthew P.; Brasher, Anne M. D.

    2011-01-01

    The Chokosna, Gilahina, and Lakina River basins, and the Long Lake watershed are located along McCarthy Road in Wrangell–St. Elias National Park and Preserve. The rivers and lake support a large run of sockeye (red) salmon that is important to the commercial and recreational fisheries in the larger Copper River. To gain a better understanding of the water quality conditions of these watersheds, these basins were studied as part of a cooperative study with the National Park Service during the open water periods in 2007 and 2008. Water type of the rivers and Long Lake is calcium bicarbonate with the exception of that in the Chokosna River, which is calcium bicarbonate sulfate water. Alkalinity concentrations ranged from 63 to 222 milligrams per liter, indicating a high buffering capacity in these waters. Analyses of streambed sediments indicated that concentrations of the trace elements arsenic, chromium, and nickel exceed levels that might be toxic to fish and other aquatic organisms. However, these concentrations reflect local geology rather than anthropogenic sources in this nearly pristine area. Benthic macroinvertebrate qualitative multi-habitat and richest targeted habitat samples collected from six stream sites along McCarthy Road indicated a total of 125 taxa. Insects made up the largest percentage of macroinvertebrates, totaling 83 percent of the families found. Dipterans (flies and midges) accounted for 43 percent of all macroinvertebrates found. Analysis of the macroinvertebrate data by non-metric multidimensional scaling indicated differences between (1) sites at Long Lake and other stream sites along McCarthy Road, likely due to different basin characteristics, (2) the 2007 and 2008 data, probably from the higher rainfall in 2008, and (3) macroinvertebrate data collected in south-central Alaska, which represents a different climate zone. The richness, abundance, and community composition of periphytic algae taxa was variable between sampling sites

  5. Characterization of CDOM of river waters in China using fluorescence excitation-emission matrix and regional integration techniques

    Science.gov (United States)

    Zhao, Ying; Song, Kaishan; Shang, Yingxin; Shao, Tiantian; Wen, Zhidan; Lv, Lili

    2017-08-01

    The spatial characteristics of fluorescent dissolved organic matter (FDOM) components in river waters in China were first examined by excitation-emission matrix spectra and fluorescence regional integration (FRI) with the data collected during September to November between 2013 and 2015. One tyrosine-like (R1), one tryptophan-like (R2), one fulvic-like (R3), one microbial protein-like (R4), and one humic-like (R5) components have been identified by FRI method. Principal component analysis (PCA) was conducted to assess variations in the five FDOM components (FRί (ί = 1, 2, 3, 4, and 5)) and the humification index for all 194 river water samples. The average fluorescence intensities of the five fluorescent components and the total fluorescence intensities FSUM differed under spatial variation among the seven major river basins (Songhua, Liao, Hai, Yellow and Huai, Yangtze, Pearl, and Inflow Rivers) in China. When all the river water samples were pooled together, the fulvic-like FR3 and the humic-like FR5 showed a strong positive linear relationship (R2 = 0.90, n = 194), indicating that the two allochthonous FDOM components R3 and R5 may originate from similar sources. There is a moderate strong positive correlation between the tryptophan-like FR2 and the microbial protein-like FR4 (R2 = 0.71, n = 194), suggesting that parts of two autochthonous FDOM components R2 and R4 are likely from some common sources. However, the total allochthonous substance FR(3+5) and the total autochthonous substances FR(1+2+4) exhibited a weak correlation (R2 = 0.40, n = 194). Significant positive linear relationships between FR3 (R2 = 0.69, n = 194), FR5 (R2 = 0.79, n = 194), and chromophoric DOM (CDOM) absorption coefficient a(254) were observed, which demonstrated that the CDOM absorption was dominated by the allochthonous FDOM components R3 and R5.

  6. [Emission factors and PM chemical composition study of biomass burning in the Yangtze River Delta region].

    Science.gov (United States)

    Tang, Xi-Bin; Huang, Cheng; Lou, Sheng-Rong; Qiao, Li-Ping; Wang, Hong-Li; Zhou, Min; Chen, Ming-hua; Chen, Chang-Hong; Wang, Qian; Li, Gui-Ling; Li, Li; Huang, Hai-Ying; Zhang, Gang-Feng

    2014-05-01

    The emission characteristics of five typical crops, including wheat straw, rice straw, oil rape straw, soybean straw and fuel wood, were investigated to explore the gas and particulates emission of typical biomass burning in Yangzi-River-Delta area. The straws were tested both by burning in stove and by burning in the farm with a self-developed measurement system as open burning sources. Both gas and fine particle pollutants were measured in this study as well as the chemical composition of fine particles. The results showed that the average emission factors of CO, NO, and PM2,5 in open farm burning were 28.7 g.kg -1, 1.2 g.kg-1 and 2.65 g kg-1 , respectively. Due to insufficient burning in the low oxygen level environment, the emission factors of stove burning were higher than those of open farm burning, which were 81.9 g kg-1, 2. 1 g.kg -1 and 8.5 gkg -1 , respectively. Oil rape straw had the highest emission factors in all tested straws samples. Carbonaceous matter, including organic carbon(OC) and element carbon(EC) , was the foremost component of PM2, 5from biomass burning. The average mass fractions of OC and EC were (38.92 +/- 13.93)% and (5.66 +/-1.54)% by open farm burning and (26.37 +/- 10. 14)% and (18.97 +/- 10.76)% by stove burning. Water soluble ions such as Cl-and K+ had a large contribution. The average mass fractions of CI- and K+ were (13.27 +/-6. 82)% and (12.41 +/- 3.02)% by open farm burning, and were (16.25 +/- 9.34)% and (13.62 +/- 7.91)% by stove burning. The K +/OC values of particles from wheat straw, rice straw, oil rape straw and soybean straw by open farm burning were 0. 30, 0. 52, 0. 49 and 0. 15, respectively, which can be used to evaluate the influence on the regional air quality in YRD area from biomass burning and provide direct evidence for source apportionment.

  7. Reconnaissance survey of site 7 of the proposed Three Rivers Regional Landfill and Technology Center, Savannah River Site, Aiken County, South Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Cabak, M.A.; Beck, M.L.; Gillam, C.; Sassaman, K.E.

    1996-02-01

    This report documents the archaeological investigation of Site 7 of the proposed Three Rivers Regional Landfill and Technology Center in Aiken County on the United States Department of Energy`s Savannah River Site (SRS) in Aiken and Barnwell Counties, South Carolina. Pedestrian and subsurface survey techniques were used to investigate the 1,403-acre project area. Survey resulted in the discovery of 23 previously unrecorded sites and 11 occurrences; six previously recorded sites were also investigated. These sites consist of six prehistoric sites, nine historic sites, and 14 sites with both prehistoric and historic components. Sites locations and project area boundaries are provided on a facsimile of a USGS 7.5 topographic map. The prehistoric components consist of very small, low-density lithic and ceramic scatters; most contain less than 10 artifacts. Six of the prehistoric components are of unknown cultural affiliation, the remaining prehistoric sites were occupied predominately in the Woodland period. The historic sites are dominated by postbellum/modem home places of tenant and yeoman farmers but four historic sites were locations of antebellum house sites (38AK136, 38AK613, 38AK660, and 38AK674). The historic sites also include an African-American school (38AK677).

  8. Uranium budget of the Thames River, Ontario, Great Lakes Region: partitioning between dissolved and microorganism components

    International Nuclear Information System (INIS)

    Mann, H.; Fyfe, W.S.

    1987-01-01

    The average level of dissolved U in the Thames River of southern Ontario is 1.45 ± 0.61 ppb, representing about twice the global mean riverine U solute concentration of 0.6 ppb. Systematic seasonal variations of dissolved U occur, peaking over the fall and winter months September-February, contrasting with depressed levels during the spring and summer: the winter and fall peaks correlate with higher discharge rates during thawing and rainfall maxima respectively, and the peak during thawing is probably indigenous to a transient melt-water surge. Whereas variations in discharge rate of up to 100-fold occur over a year, the magnitude of differences in aqueous U are at most a factor of 2, such that the U supply to the river is over-compensated for by extra water in the river system. Algae are abundant in Thames River waters at all seasons, constituting a significant fraction of the suspended > 0.45-μm particulates: they have enhanced U contents of 10 3 -10 5 times that of the river water, and an average of 28,000 ppb U. The average weight of suspended algae in river water is 9.7 mg l -1 (± 6.6 1σ), and these microorganisms carry ∼ 15% of the total riverine U flux. A correlation exists between levels of dissolved U and the U abundance of suspended algae, implying a relatively uniform partitioning of U between algae and water of 2x10 4 . 13 refs.; 7 figs.; 2 tabs

  9. Cross-scale intercomparison of climate change impacts simulated by regional and global hydrological models in eleven large river basins

    Energy Technology Data Exchange (ETDEWEB)

    Hattermann, F. F.; Krysanova, V.; Gosling, S. N.; Dankers, R.; Daggupati, P.; Donnelly, C.; Flörke, M.; Huang, S.; Motovilov, Y.; Buda, S.; Yang, T.; Müller, C.; Leng, G.; Tang, Q.; Portmann, F. T.; Hagemann, S.; Gerten, D.; Wada, Y.; Masaki, Y.; Alemayehu, T.; Satoh, Y.; Samaniego, L.

    2017-01-04

    Ideally, the results from models operating at different scales should agree in trend direction and magnitude of impacts under climate change. However, this implies that the sensitivity of impact models designed for either scale to climate variability and change is comparable. In this study, we compare hydrological changes simulated by 9 global and 9 regional hydrological models (HM) for 11 large river basins in all continents under reference and scenario conditions. The foci are on model validation runs, sensitivity of annual discharge to climate variability in the reference period, and sensitivity of the long-term average monthly seasonal dynamics to climate change. One major result is that the global models, mostly not calibrated against observations, often show a considerable bias in mean monthly discharge, whereas regional models show a much better reproduction of reference conditions. However, the sensitivity of two HM ensembles to climate variability is in general similar. The simulated climate change impacts in terms of long-term average monthly dynamics evaluated for HM ensemble medians and spreads show that the medians are to a certain extent comparable in some cases with distinct differences in others, and the spreads related to global models are mostly notably larger. Summarizing, this implies that global HMs are useful tools when looking at large-scale impacts of climate change and variability, but whenever impacts for a specific river basin or region are of interest, e.g. for complex water management applications, the regional-scale models validated against observed discharge should be used.

  10. Divergent Developmental Trajectories and Strategic Coupling in the Pearl River Delta: Where Is a Sustainable Way of Regional Economic Growth?

    Directory of Open Access Journals (Sweden)

    Yi Liu

    2017-10-01

    Full Text Available This paper interprets regional economic sustainability in the context of the globalization of late-coming regions. Drawing upon the concept of strategic coupling from economic geography, this paper proposes two types of strategic coupling, captive and proactive coupling, for better understanding regional sustainability and resilience through the experiences of the Pearl River Delta in China. It finds that sub-regional economies under captive coupling become highly dependent on exogenous growth and are vulnerable to external shocks. This trajectory looks less sustainable according to the general understanding, but it interestingly shows better resilience during and after the 2008 global financial crisis. In contrast, the ones under proactive coupling are less volatile, but growing much slower and are less resilient. By reporting these regional economic dynamics, this paper argues that sustainability in late-coming regions cannot be explained by either intra-regional forces or the means of global integration alone. In contrast, it has to be explained by the combination of both; the alleged strategic coupling in which economic growth and learning happens. This paper thus calls for greater attention to strategic coupling, the trade-off of globalization and resilience for understanding regional sustainability, rather than purely focusing on resource utilization and ecological balance.

  11. Concordance between macrophytes and macroinvertebrates in a Mediterranean river of central Apennine region.

    Science.gov (United States)

    Traversetti, Lorenzo; Scalici, Massimiliano; Ginepri, Valeria; Manfrin, Alessandro; Ceschin, Simona

    2014-05-01

    The main aim of this study was to improve the knowledge about the concordance among macrophytes and macroinvertebrates to provide complementary information and facilitate the procedures for quality assessment of river ecosystems. Macrophytes and macroinvertebrates were collected in 11 sampling sites along a central Apennine calcareous river in October 2008 and June 2009. The concordance between the two biomonitoring groups was tested according to several environmental parameters. The comparison of data matrix similarities by Mantel test showed differences in the assemblage of macrophytes and macroinvertebrates along the river since correlation values were 0.04, p > 0.05 in October 2008 and 0.39, p > 0.05 in June 2009. The study revealed lack of concordance between the two groups, emphasizing that the information provided by macrophytes and macroinvertebrates does not overlap in terms of response to environmental parameters. Indeed, the two different biological groups resulted useful descriptors of different parameters. Together, they could represent a complementary tool to reflect the river environmental quality.

  12. River water quality in the northern sugarcane-producing regions of ...

    African Journals Online (AJOL)

    Sugarcane is the major irrigated crop with regards to area cultivated in the Crocodile, Komati-Lomati and Pongola River catchments. Increasing demand for and use of water resources in these catchments has led to concerns about deterioration in water quality. In this study, chemical water quality data obtained from the ...

  13. Alaska Public Offices Commission, Department of Administration, State of

    Science.gov (United States)

    Visiting Alaska State Employees State of Alaska Department of Administration Alaska Public Offices Commission Alaska Department of Administration, Alaska Public Offices Commission APOC Home Commission Filer ; AO's Contact Us Administration > Alaska Public Offices Commission Alaska Public Offices Commission

  14. Cambrian trilobites with Siberian affinities, southwestern Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, A.R.; Egbert, R.M.; Sullivan, R.; Knoth, J.S.

    1985-02-01

    Cambrian trilobites occur in two levels (about 7 m apart) in the core of a large, complex anticlinal structure in the area between the Taylor Mountains and the Hoholitna River in southwestern Alaska. The lower collection contains Erbia, Macannaia (a species close to Soviet forms described as Pagetia ferox Lermontova), two species of Kootenia (including one perhaps cospecific with forms from the central Brooks range), and several species of ptychoparioid trilobites. It is clear that biogeographic affinities are with the transitional facies of the eastern Siberian platform and the south Siberian foldbelt. In Soviet terms, the age of the collection falls in a disputed interval called latest Early Cambrian (Tojonian) by some authors, and earliest Middle Cambrian (Amgan) by others. In North American terms, Macannaia is known only from early Middle Cambrian beds. The younger collection contains abundant agnostids, a variety of conocoryphids, Paradoxides, and several species of ptychoparioid trilobites. This is an assemblage of undoubted late Middle Cambrian age, comparable to faunas described from the Maya State of the Siberian platform and the Paradoxides paradoxissimus Stage of the Baltic region. Both faunas are from ocean-facing or outer shelf environments. None of the key non-agnostid or non-pagetiid elements have been seen previously in deposits of Cambrian North America.

  15. 75 FR 48298 - Groundfish Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea/Aleutian Islands Crab...

    Science.gov (United States)

    2010-08-10

    ... exclusion memorandum may be obtained from the Alaska Region website at http://alaskafisheries.noaa.gov... 680-SHELLFISH FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA 1. The authority citation for part...

  16. Case history of the discovery of the Jabiluka uranium deposits, East Alligator River region, Northern Territory of Australia

    International Nuclear Information System (INIS)

    Rowntree, J.C.; Mosher, D.V.

    1976-01-01

    Pancontinental Mining Limited acquired exploration rights over an area in the East Alligator River Region, Northern Territory, Australia, in 1970. Subsequently, Getty Oil Development Company Limited acquired a substantial minority interest in the property. The Jabiluka deposits were discovered during the course of exploration and are currently the largest of the four major uranium deposits in the East Alligator River Region. This region at present contains 24% of the western world's reasonably assured resources of uranium. The exploration techniques employed during primary and secondary exploration on the property between 1971 and 1975 and during the delineation of the Jabiluka deposits are discussed in detail. The case history illustrates the exploration philosophy which was successfully employed on the Jabiluka property. The philosophy encompasses the following points: The need for an assessment on the limits of airborne radiometric surveys; the necessity for detection and evaluation of point source anomalies; the necessity for exploration along extensions of favourable lithologies; and the desirability of modification of exploration techniques on different types of anomalies. Some aspects of this philosophy may be useful in exploration for similar stratabound uranium deposits in other areas. (author)

  17. Regional and Household Adaptation Strategies to Climate Extremes: the Case Study of the Beava River Basin, the Czech Republic

    Science.gov (United States)

    Duží, Barbora; Stojanov, Robert; Vikhrov, Dmytro

    2013-04-01

    We investigate regional and household adaptation strategies in the region affected by climate extremes, focusing on floods occurrence during past 15 years period. The main research question is: What is the overall state of adaptation measurements to climate extremes on the Bečva river basin? Target area is located along upper and middle part of the Bečva river basin in the east of the Czech Republic. The main theoretical concepts draw from differentiations between coping/adaptation strategies to climate extremes and theory of focusing event as a starter of changes in attention and agenda of problem solution. We apply mixed empirical research and case study approach. First we use qualitative research to serve as an initial entrance to the issue, to find out the perception of adaptation progress and preparedness to climate extremes on regional level. We conducted deep interviews (N=20) with relevant stakeholders. We proceed with quantitative research through the conducting face-to face questionnaires with household residents (N=305) in no, low and no risk area in relation to flood occurrence. We designed set of questions to find out relation among experiences with flood, the level of damages and applied emergency and adaptation measurements.

  18. Spatio-temporal variation of precipitation in the Three-River Headwater Region from 1961 to 2010

    Institute of Scientific and Technical Information of China (English)

    YI Xiangsheng; LI Guosheng; YIN Yanyu

    2013-01-01

    Based on a monthly dataset of precipitation time series (1961-2010) from 12 meteorological stations across the Three-River Headwater Region (THRHR) of Qinghai Province,China,the spatio-temporal variation and abrupt change analysis of precipitation were examined by using moving average,linear regression,spline interpolation,the Mann-Kendall test and so on.Major conclusions were as follows.(1) The long-term annual and seasonal precipitation in the study area indicated an increasing trend with some oscillations during 1961-2010; however,the summer precipitation in the Lantsang (Lancang) River Headwater Region (LARHR),and the autumn precipitation in the Yangtze River Headwater Region (YERHR) of the THRHR decreased in the same period.(2) The amount of annual precipitation in the THRHR and its three sub-headwater regions was greater in the 1980s and 2000s.The springs were fairly wet after the 1970s,while the summers were relatively wet in the 1960s,1980s and 2000s.In addition,the amount of precipitation in the autumn was greater in the 1970s and 1980s,but it was relatively less for the winter precipitation,except in the 1990s.(3) The normal values of spring,summer,winter and annual precipitation in the THRHR and its three sub-headwater regions all increased,but the normal value of summer precipitation in the LARHR had a negative trend and the normal value of winter precipitation declined in general.(4) The spring and winter precipitation increased in most of the THRHR.The summer,autumn and annual precipitation increased mainly in the marginal area of the west and north and decreased in the regions of Yushu,Zaduo,Jiuzhi and Banma.(5) The spring and winter precipitation in the THRHR and its three sub-headwater regions showed an abrupt change,except for the spring precipitation in the YARHR.The abrupt changes of spring precipitation were mainly in the late 1980s and early 1990s,while the abrupt changes of winter precipitation were primary in the mid-to late 1970s

  19. Tropospheric aerosols radiation feedback on the climate of Pearl River Delta Region using an air quality model

    Science.gov (United States)

    Nduka, I. C.

    2016-12-01

    The Pearl River Delta (PRD) region, one of the most vibrant economic regions in China has been witnessing rapid population, economic and structural growth and development. It is also one of the regions mostly polluted with trace gases and particulates. Recent reviews show large uncertainties in climate modification studies, indicating the need for further investigations, such as the role of tropospheric aerosols on direct and indirect climate modification. The aim of this research is to appraise the impacts of tropospheric aerosols on the climate of PRD region. An integrated air quality downscale meteorology and air quality from regional scale (27km) to local scale (3km). The model will be evaluated for both meteorology and air quality by comparing model results with measurements. The radiative forcing of tropospheric aerosols will also be determined so as to estimate the feedbacks and impacts on the climate. This research, when completed, is expected to improve our understanding of tropospheric aerosol-cloud thermodynamic interactions at regional and local scales, thus enhancing our knowledge of the regional and local climate system, which is anticipated to provide critical references for formulating sustainable environment and air quality policies.

  20. Crustal Structure beneath Alaska from Receiver Functions

    Science.gov (United States)

    Zhang, Y.; Li, A.

    2017-12-01

    The crustal structure in Alaska has not been well resolved due to the remote nature of much of the state. The USArray Transportable Array (TA), which is operating in Alaska and northwestern Canada, significantly increases the coverage of broadband seismic stations in the region and allows for a more comprehensive study of the crust. We have analyzed P-receiver functions from earthquake data recorded by 76 stations of the TA and AK networks. Both common conversion point (CCP) and H-K methods are used to estimate the mean crustal thickness. The results from the CCP stacking method show that the Denali fault marks a sharp transition from thick crust in the south to thin crust in the north. The thickest crust up to 52 km is located in the St. Elias Range, which has been formed by oblique collision between the Yakutat microplate and North America. A thick crust of 48 km is also observed beneath the eastern Alaska Range. These observations suggest that high topography in Alaska is largely compensated by the thick crust root. The Moho depth ranges from 28 km to 35 km beneath the northern lowlands and increases to 40-45 km under the Books Range. The preliminary crustal thickness from the H-K method generally agrees with that from the CCP stacking with thicker crust beneath high mountain ranges and thinner crust beneath lowlands and basins. However, the offshore part is not well constrained due to the limited coverage of stations. The mean Vp/Vs ratio is around 1.7 in the Yukon-Tanana terrane and central-northern Alaska. The ratio is about 1.9 in central and southern Alaska with higher values at the Alaska Range, Wrangell Mountains, and St. Elias Range. Further data analyses are needed for obtaining more details of the crustal structure in Alaska to decipher the origin and development of different tectonic terranes.

  1. Modeling of Regionalized Emissions (MoRE into Water Bodies: An Open-Source River Basin Management System

    Directory of Open Access Journals (Sweden)

    Stephan Fuchs

    2017-03-01

    Full Text Available An accurate budget of substance emissions is fundamental for protecting freshwater resources. In this context, the European Union asks all member states to report an emission inventory of substances for river basins. The river basin management system MoRE (Modeling of Regionalized Emissions was developed as a flexible open-source instrument which is able to model pathway-specific emissions and river loads on a catchment scale. As the reporting tool for the Federal Republic of Germany, MoRE is used to model annual emissions of nutrients, heavy metals, micropollutants like polycyclic aromatic hydrocarbons (PAH, Bis(2-ethylhexylphthalate (DEHP, and certain pharmaceuticals. Observed loads at gauging stations are used to validate the calculated emissions. In addition to its balancing capabilities, MoRE can consider different variants of input data and quantification approaches, in order to improve the robustness of different modeling approaches and to evaluate the quality of different input data. No programming skills are required to set up and run the model. Due to its flexible modeling base, the effect of reduction measures can be assessed. Within strategic planning processes, this is relevant for the allocation of investments or the implementation of specific measures to reduce the overall pollutant emissions into surface water bodies and therefore to meet the requirements of water policy.

  2. Alaska Kids' Corner, State of Alaska

    Science.gov (United States)

    /Fishing License Get a Birth Certificate, Marriage License, etc. Alaska Permanent Fund Dividend Statewide shocks of wheat represent Alaskan agriculture. The fish and the seals signify the importance of fishing

  3. Glaciers of North America - Glaciers of Alaska

    Science.gov (United States)

    Molnia, Bruce F.

    2008-01-01

    Glaciers cover about 75,000 km2 of Alaska, about 5 percent of the State. The glaciers are situated on 11 mountain ranges, 1 large island, an island chain, and 1 archipelago and range in elevation from more than 6,000 m to below sea level. Alaska's glaciers extend geographically from the far southeast at lat 55 deg 19'N., long 130 deg 05'W., about 100 kilometers east of Ketchikan, to the far southwest at Kiska Island at lat 52 deg 05'N., long 177 deg 35'E., in the Aleutian Islands, and as far north as lat 69 deg 20'N., long 143 deg 45'W., in the Brooks Range. During the 'Little Ice Age', Alaska's glaciers expanded significantly. The total area and volume of glaciers in Alaska continue to decrease, as they have been doing since the 18th century. Of the 153 1:250,000-scale topographic maps that cover the State of Alaska, 63 sheets show glaciers. Although the number of extant glaciers has never been systematically counted and is thus unknown, the total probably is greater than 100,000. Only about 600 glaciers (about 1 percent) have been officially named by the U.S. Board on Geographic Names (BGN). There are about 60 active and former tidewater glaciers in Alaska. Within the glacierized mountain ranges of southeastern Alaska and western Canada, 205 glaciers (75 percent in Alaska) have a history of surging. In the same region, at least 53 present and 7 former large ice-dammed lakes have produced jokulhlaups (glacier-outburst floods). Ice-capped volcanoes on mainland Alaska and in the Aleutian Islands have a potential for jokulhlaups caused by subglacier volcanic and geothermal activity. Because of the size of the area covered by glaciers and the lack of large-scale maps of the glacierized areas, satellite imagery and other satellite remote-sensing data are the only practical means of monitoring regional changes in the area and volume of Alaska's glaciers in response to short- and long-term changes in the maritime and continental climates of the State. A review of the

  4. Agro-extractivist value chains and regional development: the case of the Lower Tocantins River in the Brazilian Amazon

    OpenAIRE

    Dürr, Jochen

    2014-01-01

    The Lower Tocantins river region offers a wide range of agricultural and extractive products like açaí palm fruits, pepper, oil palms and manioc, which are produced for local and national consumption and for exports. These products do not only generate value added in the agricultural sector, but also indirectly in other sectors like agro-industry and commerce. The value chains of agricultural and extractive products form the basis of the rural economy and hence for the development of the nine...

  5. Parasitism of the isopod Artystone trysibia in the fish Chaetostoma dermorhynchum from the Tena River (Amazonian region, Ecuador).

    Science.gov (United States)

    Junoy, Juan

    2016-01-01

    The isopod Artystone trysibia Schioedte, 1866 is described by using a collection of specimens that were found parasitizing loricariid fish Chaetostoma dermorhynchum Boulenger, 1887 in the Tena River (Napo province, Ecuador, Amazonian region). Additionally to freshly collected specimens, complementary data of the parasite was obtained from preserved fishes at Ecuadorian museums. This is the first record of A. trysibia in Ecuador, and the most upstream location for the species. The new host fish, Chaetostoma dermorhynchum, is used locally as food. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Multi-scale response of runoff to climate fluctuation in the headwater region of Kaidu River in Xinjiang of China

    Science.gov (United States)

    Bai, Ling; Chen, Zhongsheng; Xu, Jianhua; Li, Weihong

    2016-08-01

    Based on the hydrological and meteorological data in the headwater region of the Kaidu River during 1960-2009, the multi-scale characteristics of runoff variability were analyzed using the ensemble empirical mode decomposition method (EEMD), and the aim is to investigate the oscillation mode structure characteristics of runoff change and its response to climate fluctuation at different time scales. Results indicated that in the past 50 years, the overall runoff of Kaidu River in Xinjiang has showed a significant nonlinear upward trend, and its changes have obviously exhibited an inter-annual scale (quasi-3 and quasi-6-year) and inter-decadal scale (quasi-10 and quasi-25-year). Variance contribution rates of each component manifested that the inter-decadal change had been playing a more important role in the overall runoff change for Kaidu River, and the reconstructed inter-annual variation trend could describe the fluctuation state of the original runoff anomaly during the study period. The reconstructed inter-decadal variability effectively revealed that the runoff for Kaidu River changed over the years, namely the states of abundance and low water period appear alternately. In addition, we found that runoff has a positive correlation to precipitation and temperature at different time scales, but they are most significant and relevant at inter-decadal scale, indicating the inter-decadal scale is most suitable for investigating the responses of runoff dynamics to climate fluctuation. At the same time, the results also suggested that EEMD is an effective method to analyze the multi-scale characteristics of nonlinear and non-stationary signal.

  7. Effect of ecological restoration and climate change on ecosystems: a case study in the Three-Rivers Headwater Region, China.

    Science.gov (United States)

    Jiang, Chong; Zhang, Linbo

    2016-06-01

    The Three-Rivers Headwater Region (TRHR) is the headwater of the Yangtze River Basin (YARB), Yellow River Basin (YRB), and Lancang River Basin (LRB); it is known as China's 'Water Tower' owing to its important supply of freshwater. In order to assess ecosystem changes in the TRHR during 2000-2012, we systematically and comprehensively evaluated a combination of model simulation results and actual observational data. The results showed the following: (1) Ecosystem pattern was relatively stable during 2000-2010, with a slight decrease in farmland and desert areas, and a slight increase in grassland and wetland/water-body areas. (2) A warmer and wetter climate, and ecological engineering, caused the vegetation cover and productivity to significantly improve. (3) Precipitation was the main controlling factor for streamflow. A significant increase in precipitation during 2000-2012 resulted in an obvious increase in annual and seasonal streamflow. Glacier melting also contributed to the streamflow increase. (4) The total amount of soil conservation increased slightly from 2000 to 2012. The increase in precipitation caused rainfall erosivity to increase, which enhanced the intensity of soil erosion. The decrease in wind speed decreased wind erosion and the frequency of sandstorms. (5) The overall habitat quality in the TRHR was stable between 2000 and 2010, and the spatial pattern exhibited obvious heterogeneity. In some counties that included nature reserves, habitat quality was slightly higher in 2010 than in 2000, which reflected the effectiveness of the ecological restoration. Overall, the aforementioned ecosystem changes are the combined results of ecological restoration and climate change, and they are likely a local and temporary improvement, rather than a comprehensive and fundamental change. Therefore, more investments and efforts are needed to preserve natural ecosystems.

  8. Spatial and temporal variability in the Quality of Surface water in a semi-arid mediterranean region (river orontes- Lebanon)

    International Nuclear Information System (INIS)

    SLIM, K.; SAAD, Z.; KAZPARD, V.; EL SAMAD, O.; NASREDDINE, M.

    2004-01-01

    The Orontes River is an international river, with its headwaters in Lebanon, its middle section in Syria and its mouth in Turkey. Fresh surface waters were sampled monthly during the year 2000 and analyzed for major ions and for trace metals. Sea-salt aerosols in rainwater partially influence the major ion composition in the river. The concentration of major cations and anions fall within the range of the most common natural Concentration of major ion assemblages established for world river(MCNC), with a cation and anion dominance in the order of Ca > Mg > Na> K and HCO3 > SO4 > Cl, which tend to be predominantly influenced by chemical weathering of rocks and minerals in a semi-arid region. Ca and HCO3 are mostly derived from the dissolution of carbonate rocks. The sources of SO4 could be attributed to anhydrite minerals and to anthropogenic impact from fertilizers. Increases in nutrient concentrations are attributed mainly to the increasing influence of agricultural runoff. δ18 0/ δH plots shows that the data either fits the Mediterranean Meteoric Water Line(MMWL) or have elevated values that indicate evaporative isotope enrichment in a semi-arid climate. The correlation matrix for trace elements shows a high coefficient of correlation for Fe, Zn and Cu indicating that these elements could be controlled by the same chemistry in water. The bicarbonate-alkaline type of Orontes surface water contribute to the formation of trace metals-carbonate complexes such as FeCO3(aq) and ZnCO3 (aq). The good correlation between Pb, Cd and Cr reflects the effect of increasing urbanization in the catchments. (author)

  9. Isotope hydrology study of Kalamos region (Attiki) and of the Assopos river basin

    International Nuclear Information System (INIS)

    Leontiadis, J.L.

    1980-10-01

    The isotopic composition of the water was used to determine the mechanism of recharge of the Assopos river basin and that of the Kalamos springs issuing brackish water near the coast. The results of the study permitted the catchment of the water before its salinization. A quantity of 73000 m 3 per day is now pumped and used as additional drinkable water for the major area of Athens covering about the 1/6 of the corresponding mean daily consumption. (T.A.)

  10. Alaska Consumer Protection Unit

    Science.gov (United States)

    Drafting Manual Attorney General Opinions Executive Branch Ethics Criminal Justice Alaska Medicaid Fraud make wise purchasing decisions and avoid becoming victims of consumer fraud. The site also includes

  11. Regulatory Commission of Alaska

    Science.gov (United States)

    Map Help Regulatory Commission of Alaska Login Forgot Password Arrow Image Forgot password? View Cart login Procedures for Requesting Login For Consumers General Information Telephone Electric Natural Gas

  12. Development and application of a novel method for regional assessment of groundwater contamination risk in the Songhua River Basin.

    Science.gov (United States)

    Nixdorf, Erik; Sun, Yuanyuan; Lin, Mao; Kolditz, Olaf

    2017-12-15

    The main objective of this study is to quantify the groundwater contamination risk of Songhua River Basin by applying a novel approach of integrating public datasets, web services and numerical modelling techniques. To our knowledge, this study is the first to establish groundwater risk maps for the entire Songhua River Basin, one of the largest and most contamination-endangered river basins in China. Index-based groundwater risk maps were created with GIS tools at a spatial resolution of 30arc sec by combining the results of groundwater vulnerability and hazard assessment. Groundwater vulnerability was evaluated using the DRASTIC index method based on public datasets at the highest available resolution in combination with numerical groundwater modelling. As a novel approach to overcome data scarcity at large scales, a web mapping service based data query was applied to obtain an inventory for potential hazardous sites within the basin. The groundwater risk assessment demonstrated that contamination risk. These areas were mainly located in the vast plain areas with hotspots particularly in the Changchun metropolitan area. Moreover, groundwater levels and pollution point sources were found to play a significantly larger impact in assessing these areas than originally assumed by the index scheme. Moderate contamination risk was assigned to 27% of the aquifers, predominantly associated with less densely populated agricultural areas. However, the majority of aquifer area in the sparsely populated mountain ranges displayed low groundwater contamination risk. Sensitivity analysis demonstrated that this novel method is valid for regional assessments of groundwater contamination risk. Despite limitations in resolution and input data consistency, the obtained groundwater contamination risk maps will be beneficial for regional and local decision-making processes with regard to groundwater protection measures, particularly if other data availability is limited. Copyright

  13. Differential environmental impacts on small and medium size rivers from center of São Paulo State, Brazil, and regional management perspectives

    Directory of Open Access Journals (Sweden)

    Paula Caroline dos Reis Oliveira

    2014-12-01

    Full Text Available AIM: This study aimed to evaluate, comparatively, the influence of distinct environmental impacts in the watershed on the rivers Capivara, Lavapés, Araquá and Pardo and the transference of effects downstream. METHODS: The limnological/water quality study was carried out in rainy (March/2007 and dry (September/2007 seasons, considering 17 sampling stations. RESULTS: Variables such as channel width and depth, water velocity and temperature increased towards the river's mouth; water transparency, velocity and dissolved oxygen were higher in the upstream regions. Light penetration was total at most sampling stations and pH was predominantly acid. The sampling stations impacted by pollution sources, Lavapés and Araquá Rivers, exhibited higher values of electric conductivity, suspended solids, total nitrogen, nitrate, nitrite, ammonium, total dissolved phosphorus, BOD, and thermotolerant coliforms. Higher values of electric conductivity, turbidity and suspended solids were observed in the rainy season, whereas higher chlorophyll concentrations occurred in the dry season. The Lavapés River exhibits the worst environmental condition, while Capivara River is under better state of conservation. This study shows that it is urgent the implementation of measures for preservation and restoration of these regional aquatic ecosystems. All studied rivers were influenced by seasonal variation, sewage discharges and by watershed use and occupation. The TSI is a good analysis tool. The studied rivers export organic matter and TN, TP and SS loads to Tietê and Paranapanema rivers. CONCLUSIONS: This study show the importance of river management and that the accelerated degradation of the river systems indicates the little progress of the Brazilian legislation in terms of preservation and good management practices and that the interface between science, law, management and conservation need to be improved.

  14. Source areas and chemical composition of fine particulate matter in the Pearl River Delta region of China

    Science.gov (United States)

    Hagler, G. S. W.; Bergin, M. H.; Salmon, L. G.; Yu, J. Z.; Wan, E. C. H.; Zheng, M.; Zeng, L. M.; Kiang, C. S.; Zhang, Y. H.; Lau, A. K. H.; Schauer, J. J.

    Fine particulate matter (PM 2.5) was measured for 4 months during 2002-2003 at seven sites located in the rapidly developing Pearl River Delta region of China, an area encompassing the major cities of Hong Kong, Shenzhen and Guangzhou. The 4-month average fine particulate matter concentration ranged from 37 to 71 μg m -3 in Guangdong province and from 29 to 34 μg m -3 in Hong Kong. Main constituents of fine particulate mass were organic compounds (24-35% by mass) and sulfate (21-32%). With sampling sites strategically located to monitor the regional air shed patterns and urban areas, specific source-related fine particulate species (sulfate, organic mass, elemental carbon, potassium and lead) and daily surface winds were analyzed to estimate influential source locations. The impact of transport was investigated by categorizing 13 (of 20 total) sampling days by prevailing wind direction (southerly, northerly or low wind-speed mixed flow). The vicinity of Guangzhou is determined to be a major source area influencing regional concentrations of PM 2.5, with levels observed to increase by 18-34 μg m -3 (accounting for 46-56% of resulting particulate levels) at sites immediately downwind of Guangzhou. The area near Guangzhou is also observed to heavily impact downwind concentrations of lead. Potassium levels, related to biomass burning, appear to be controlled by sources in the northern part of the Pearl River Delta, near rural Conghua and urban Guangzhou. Guangzhou appears to contribute 5-6 μg m -3 of sulfate to downwind locations. Guangzhou also stands out as a significant regional source of organic mass (OM), adding 8.5-14.5 μg m -3 to downwind concentrations. Elemental carbon is observed to be strongly influenced by local sources, with highest levels found in urban regions. In addition, it appears that sources outside of the Pearl River Delta contribute a significant fraction of overall fine particulate matter in Hong Kong and Guangdong province. This is evident

  15. Effects of sediment quality on macroinvertebrates in the Sunraysia region of the Murray-Darling Rivers, Australia

    Energy Technology Data Exchange (ETDEWEB)

    Sharley, David J. [Centre for Environmental Stress and Adaptation Research-Hoffmann Laboratory, Zoology Department, University of Melbourne, Level 2, Bio 21 Institute, 30 Flemington Road, Parkville, Victoria 3010 (Australia)], E-mail: sharleyd@unimelb.edu.au; Hoffmann, Ary A. [Centre for Environmental Stress and Adaptation Research-Hoffmann Laboratory, Zoology Department, University of Melbourne, Level 2, Bio 21 Institute, 30 Flemington Road, Parkville, Victoria 3010 (Australia); Pettigrove, Vincent [Research and Technology, Melbourne Water, PO Box 4342, Melbourne, Victoria 3001 (Australia)

    2008-12-15

    A field-based microcosm approach was tested to identify deterioration of sediment quality in waterways using freshwater macroinvertebrates. The method can potentially identify the nature of contaminants based on species-specific responses. Sediments were collected from the Murray and Darling Rivers and irrigation drains within the Sunraysia region of south-eastern Australia and compared to non-polluted reference sediment. Clean sediments were also spiked with fertiliser to test whether nutrients affected the aquatic fauna. Seven of the eight sediments from the Sunraysia region had a negative impact on the macroinvertebrates, in particular sediment from the Darling River, which supported an impoverished fauna. Three species of chironomid showed varied responses to sediment quality and, although it was hypothesised that nutrients may have impacted on the macroinvertebrate fauna, the results suggest that other pollutants are also involved. The field-based microcosm method proved effective for determining the impact of sediment quality on indigenous macroinvertebrates. - Sediment quality effects on freshwater macroinvertebrates are isolated.

  16. Using NASA's Giovanni System to Simulate Time-Series Stations in the Outflow Region of California's Eel River

    Science.gov (United States)

    Acker, James G.; Shen, Suhung; Leptoukh, Gregory G.; Lee, Zhongping

    2012-01-01

    Oceanographic time-series stations provide vital data for the monitoring of oceanic processes, particularly those associated with trends over time and interannual variability. There are likely numerous locations where the establishment of a time-series station would be desirable, but for reasons of funding or logistics, such establishment may not be feasible. An alternative to an operational time-series station is monitoring of sites via remote sensing. In this study, the NASA Giovanni data system is employed to simulate the establishment of two time-series stations near the outflow region of California s Eel River, which carries a high sediment load. Previous time-series analysis of this location (Acker et al. 2009) indicated that remotely-sensed chl a exhibits a statistically significant increasing trend during summer (low flow) months, but no apparent trend during winter (high flow) months. Examination of several newly-available ocean data parameters in Giovanni, including 8-day resolution data, demonstrates the differences in ocean parameter trends at the two locations compared to regionally-averaged time-series. The hypothesis that the increased summer chl a values are related to increasing SST is evaluated, and the signature of the Eel River plume is defined with ocean optical parameters.

  17. Effects of sediment quality on macroinvertebrates in the Sunraysia region of the Murray-Darling Rivers, Australia

    International Nuclear Information System (INIS)

    Sharley, David J.; Hoffmann, Ary A.; Pettigrove, Vincent

    2008-01-01

    A field-based microcosm approach was tested to identify deterioration of sediment quality in waterways using freshwater macroinvertebrates. The method can potentially identify the nature of contaminants based on species-specific responses. Sediments were collected from the Murray and Darling Rivers and irrigation drains within the Sunraysia region of south-eastern Australia and compared to non-polluted reference sediment. Clean sediments were also spiked with fertiliser to test whether nutrients affected the aquatic fauna. Seven of the eight sediments from the Sunraysia region had a negative impact on the macroinvertebrates, in particular sediment from the Darling River, which supported an impoverished fauna. Three species of chironomid showed varied responses to sediment quality and, although it was hypothesised that nutrients may have impacted on the macroinvertebrate fauna, the results suggest that other pollutants are also involved. The field-based microcosm method proved effective for determining the impact of sediment quality on indigenous macroinvertebrates. - Sediment quality effects on freshwater macroinvertebrates are isolated

  18. Influence of Plastic Covering on the Microclimate in Vineyards in the São Francisco River Valley Region

    Directory of Open Access Journals (Sweden)

    Mário de Miranda Vilas Boas Ramos Leitão

    Full Text Available Abstract Data from field experiments conducted in table grape vineyards variety of Festival in Petrolina-PE in the period from September 19 to October 12, 2010 were used to evaluate the influence of plastic cover on microclimate conditions of vineyards in São Francisco River Valley region. Three treatments were studied: canopies without plastic cover (WC; with plastic cover positioned at 50 cm (PC50, and at 100 cm (PC100 above canopy. The results indicate that the plastic cover prevented the passage of about 40% of the global and net radiation, retained the relative humidity inside the canopy, generated an increase of air temperature and marked reduction in wind speed over the canopy of treatment PC50. However, treatment PC100 had a higher incidence of short wavelength and net radiation under canopy (on the berries than WC and PC50 treatments, resulting in more favorable weather conditions, providing about 40% greater productivity in this treatment. Therefore, the vineyard with plastic cover placed at 100 cm above canopy represents a more suitable alternative to the climatic conditions of the region of the São Francisco River Valley.

  19. Assessment on the Effect of Climate Change on Streamflow in the Source Region of the Yangtze River, China

    Directory of Open Access Journals (Sweden)

    Huanqing Bian

    2017-01-01

    Full Text Available Tuotuo River basin, known as the source region of the Yangtze River, is the key area where the impact of climate change has been observed on many of the hydrological processes of this central region of the Tibetan Plateau. In this study, we examined six Global Climate Models (GCMs under three Representative Concentration Pathways (RCPs scenarios. First, the already impacted climate change was analyzed, based on the historical data available and then, the simulation results of the GCMs and RCPs were used for future scenario assessments. Results indicated that the annual mean temperature will likely be increased, ranging from −0.66 °C to 6.68 °C during the three future prediction periods (2020s, 2050s and 2080s, while the change in the annual precipitation ranged from −1.18% to 66.14%. Then, a well-known distributed hydrological soil vegetation model (DHSVM was utilized to evaluate the effects of future climate change on the streamflow dynamics. The seasonal mean streamflows, predicted by the six GCMs and the three RCPs scenarios, were also shown to likely increase, ranging from −0.52% to 22.58%. Watershed managers and regulators can use the findings from this study to better implement their conservation practices in the face of climate change.

  20. Improving regional climate and hydrological forecasting following the record setting flooding across the Lake Ontario - St. Lawrence River system

    Science.gov (United States)

    Gronewold, A.; Seglenieks, F.; Bruxer, J.; Fortin, V.; Noel, J.

    2017-12-01

    In the spring of 2017, water levels across Lake Ontario and the upper St. Lawrence River exceeded record high levels, leading to widespread flooding, damage to property, and controversy over regional dam operating protocols. Only a few years earlier, water levels on Lakes Superior, Michigan, and Huron (upstream of Lake Ontario) had dropped to record low levels leading to speculation that either anthropogenic controls or climate change were leading to chronic water loss from the Great Lakes. The contrast between low water level conditions across Earth's largest lake system from the late 1990s through 2013, and the rapid rise prior to the flooding in early 2017, underscores the challenges of quantifying and forecasting hydrologic impacts of rising regional air and water temperatures (and associated changes in lake evaporation) and persistent increases in long-term precipitation. Here, we assess the hydrologic conditions leading to the recent record flooding across the Lake Ontario - St. Lawrence River system, with a particular emphasis on understanding the extent to which those conditions were consistent with observed and anticipated changes in historical and future climate, and the extent to which those conditions could have been anticipated through improvements in seasonal climate outlooks and hydrological forecasts.

  1. Linking Backbarrier Lacustrine Stratigraphy with Spatial Dynamics of Shoreline Retreat in a Rapidly Subsiding Region of the Mississippi River Delta

    Science.gov (United States)

    Dietz, M.; Liu, K. B.; Bianchette, T. A.; Yao, Q.

    2017-12-01

    The shoreline along the northern Gulf of Mexico is rapidly retreating as coastal features of abandoned Mississippi River delta complexes erode and subside. Bay Champagne is located in the Caminada-Moreau headland, a region of shoreline west of the currently active delta that has one of the highest rates of retreat and land loss. As a result, this site has transitioned from a stable, circular inland lake several kilometers from the shore to a frequently perturbed, semi-circular backbarrier lagoon, making it ideal to study the environmental effects of progressive land loss. Analyses of clastic layers in a series of sediment cores collected at this site over the past decade indicate the lake was less perturbed in the past and has become increasingly more sensitive to marine incursion events caused by tropical cyclones. Geochemical and pollen analyses of these cores also reveal profound changes in environmental and chemical conditions in Bay Champagne over the past century as the shoreline has retreated. Through relating stratigraphy to spatial changes observed from satellite imagery, this study attempts to identify the tipping point at which Bay Champagne began the transition from an inland lake to a backbarrier environment, and to determine the rate at which this transition occurred. Results will be used to develop a model of the environmental transition experienced by a rapidly retreating coastline and to predict how other regions of the Mississippi River deltaic system could respond to future shoreline retreat.

  2. Palms and Palm Communities in the Upper Ucayali River Valley - a Little-Known Region in the Amazon Basin

    DEFF Research Database (Denmark)

    Balslev, Henrik; Eiserhardt, Wolf L.; Kristiansen, Thea

    2010-01-01

    The Amazon region and its palms are inseparable. Palms make up such an important part of the rain forest ecosystem that it is impossible to imagine the Amazon basin without them. Palms are visible in the canopy and often fill up the forest understory. Palms – because of their edible fruits...... – are cornerstone species for the survival of many animals, and palms contribute substantially to forest inventories in which they are often among the ten most important families. Still, the palms and palm communities of some parts of the Amazon basin remain poorly studied and little known. We travelled to a little......-explored corner of the western Amazon basin, the upper Ucayali river valley. There, we encountered 56 different palms, 18 of which had not been registered for the region previously, and 21 of them were found 150–400 km beyond their previously known limits....

  3. Chronology of Miocene-Pliocene deposits at Split Mountain Gorge, Southern California: A record of regional tectonics and Colorado River evolution

    Science.gov (United States)

    Dorsey, R.J.; Fluette, A.; McDougall, K.; Housen, B.A.; Janecke, S.U.; Axen, G.J.; Shirvell, C.R.

    2007-01-01

    Late Miocene to early Pliocene deposit at Split Mountain Gorge, California, preserve a record of basinal response to changes in regional tectonics, paleogeography, and evolution of the Colorado River. The base of the Elephant Trees Formation, magnetostratigraphically dated as 8.1 ?? 0.4 Ma, provides the earliest well-dated record of extension in the southwestern Salton Trough. The oldest marine sediments are ca. 6.3 Ma. The nearly synchronous timing of marine incursion in the Salton Trough and northern Gulf of California region supports a model for localization of Pacific-North America plate motion in the Gulf ca. 6 Ma. The first appearance of Colorado River sand at the Miocene-Pliocene boundary (5.33 Ma) suggests rapid propagation of the river to the Salton Trough, and supports a lake-spillover hypothesis for initiation of the lower Colorado River. ?? 2007 Geological Society of America.

  4. Geology, selected geophysics, and hydrogeology of the White River and parts of the Great Salt Lake Desert regional groundwater flow systems, Utah and Nevada

    Science.gov (United States)

    Rowley, Peter D.; Dixon, Gary L.; Watrus , James M.; Burns, Andrews G.; Mankinen, Edward A.; McKee, Edwin H.; Pari, Keith T.; Ekren, E. Bartlett; Patrick , William G.; Comer, John B.; Inkenbrandt, Paul C.; Krahulec, K.A.; Pinnell, Michael L.

    2016-01-01

    The east-central Great Basin near the Utah-Nevada border contains two great groundwater flow systems. The first, the White River regional groundwater flow system, consists of a string of hydraulically connected hydrographic basins in Nevada spanning about 270 miles from north to south. The northernmost basin is Long Valley and the southernmost basin is the Black Mountain area, a valley bordering the Colorado River. The general regional groundwater flow direction is north to south. The second flow system, the Great Salt Lake Desert regional groundwater flow system, consists of hydrographic basins that straddle

  5. Why is the Arkavathy River drying? A multiple hypothesis approach in a data scarce region

    Science.gov (United States)

    Srinivasan, V.; Thompson, S.; Madhyastha, K.; Penny, G.; Jeremiah, K.; Lele, S.

    2015-01-01

    The developing world faces unique challenges in achieving water security as it is disproportionately exposed to stressors such as climate change while also undergoing demographic growth, agricultural intensification and industrialization. Investigative approaches are needed that can inform sound policy development and planning to address the water security challenge in the context of data scarcity. We investigated the "predictions under change" problem in the Thippagondanahalli (TG Halli) catchment of the Arkavathy sub-basin in South India. River inflows into the TG Halli reservoir have declined since the 1970s, and the reservoir is currently operating at only 20% of its built capacity. The mechanisms responsible for the drying of the river are not understood, resulting in uncoordinated and potentially counter-productive management responses. The objective of this study was to investigate potential explanations of the drying trend and thus obtain predictive insight. We used a multiple working hypothesis approach to investigate the decline in inflow into TG Halli reservoir. Five hypotheses were tested using data from field surveys and reliable secondary sources: (1) changes in rainfall amount, timing and storm intensity, (2) rising temperatures, (3) increased groundwater extraction, (4) expansion of eucalyptus plantations, and (5) increased fragmentation of the river channel. Our results indicate that proximate anthropogenic drivers of change such as groundwater pumping, expansion of eucalyptus plantations, and to a lesser extent channel fragmentation, are much more likely to have caused the decline in surface flows in the TG Halli catchment than changing climate. The case study shows that direct human interventions play a significant role in altering the hydrology of watersheds. The multiple working hypotheses approach presents a systematic way to quantify the relative contributions of anthropogenic drivers to hydrologic change. The approach not only yields a

  6. Analysis of heavy metal flow in the river Przemsza, Katowice region, using macrophytes

    Energy Technology Data Exchange (ETDEWEB)

    Lewander, M.

    1995-06-01

    The river Przemsza, in southern Poland, was investigated with the aim to determine the flow of Cd, Pb and Zn between the submerged macrophytes Potamogeton pectinatus and Myriophyllum verticillatum, sediment and water, and to find out if a pollution gradient was present along the investigated part of the river. In order to determine the uptake of heavy metals from water and sediment macrophytes were planted in pots along the river, in unpolluted and polluted sediment during six weeks in the summer of 1993. After harvesting the plants were dried, wet digested and analysed by atomic absorption spectrophotometry. Parallel in situ experiments and outdoor experiments in sealed jars were performed. No significant decreased pollution gradient in the sediment or the macrophytes content could be detected. However, the water concentration of Zn decreased slightly along the gradient and in both experiments Pb concentration in the water also decreased. The concentrations of metals in the plants and sediments were probably depending on local stream conditions as well as increasing organic content. The study suggests that the macrophytes took up metals both from water and sediment. The unpolluted sediment accumulated Pb and Zn in both experiments, while Cd was accumulated in the in situ experiment. Metal concentration in the polluted sediment decreased during the study period, either due to plant uptake or loss to the water. Metals lost from the polluted sediment to the water were taken up by the plant shoots. Lead mainly accumulated in the roots while Zn accumulated in the plant shoots, and Cd was distributed almost equally between shoots and roots. 18 refs, 2 figs, 6 tabs

  7. Economic Analysis of the Impacts of Climate-Induced Changes in River Flow on Hydropower and Fisheries in Himalayan region.

    Science.gov (United States)

    Khadka Mishra, S.; Hayse, J.; Veselka, T.; Yan, E.; Kayastha, R. B.; McDonald, K.; Steiner, N.; Lagory, K.

    2017-12-01

    Climate-mediated changes in melting of snow and glaciers and in precipitation patterns are expected to significantly alter the water flow of rivers at various spatial and temporal scales. Hydropower generation and fisheries are likely to be impacted annually and over the century by the seasonal as well as long-term changes in hydrological conditions. In order to quantify the interactions between the drivers of climate change, the hydropower sector and the ecosystem we developed an integrated assessment framework that links climate models with process-based bio-physical and economic models. This framework was applied to estimate the impacts of changes in snow and glacier melt on the stream flow of the Trishuli River of the High Mountain Asia Region. Remotely-sensed data and derived products, as well as in-situ data, were used to quantify the changes in snow and glacier melt. The hydrological model was calibrated and validated for stream flows at various points in the Trishuli river in order to forecast conditions at the location of a stream gauge station upstream of the Trishuli hydropower plant. The flow of Trishuli River was projected to increase in spring and decrease in summer over the period of 2020-2100 under RCP 8.5 and RCP 4.5 scenarios as compared to respective mean seasonal discharge observed over 1981-2014. The simulated future annual mean stream flow would increase by 0.6 m3/s under RCP 8.5 scenario but slightly decrease under RCP 4.5. The Argonne Hydropower Energy and Economic toolkit was used to estimate and forecast electricity generation at the Trishuli power plant under various flow conditions and upgraded infrastructure. The increased spring flow is expected to increase dry-season electricity generation by 18% under RCP 8.5 in comparison to RCP 4.5. A fishery suitability model developed for the basin indicated that fishery suitability in the Trishuli River would be greater than 70% of optimal, even during dry months under both RCP 4.5 and RCP 8

  8. Regional Hydrology of the Green River-Moab Area, Northwestern Paradox Basin, Utah

    OpenAIRE

    United States Geological Survey

    1982-01-01

    The Green River-Moab area encompasses about 7,800 square kilometers or about 25 percent of the Paradox basin. The entire Paradox basin is a part of the Colorado Plateaus that is underlain by a thick sequence of evaporite (salt) beds of Pennsylvanian age. The rock units that underlie the area have been grouped into hydrogeologic units based on their water-transmitting ability. Confining beds consist of evaporite beds of mostly salt, and overlying and underlying thick sequences of rocks with...

  9. Impact of river stage prediction methods on stream-aquifer exchanges in a hydro(geo)logical model at the regional scale

    Science.gov (United States)

    Saleh, F.; Flipo, N.; de Fouquet, C.

    2012-04-01

    The main objective of this study is to provide a realistic simulation of river stage in regional river networks in order to improve the quantification of stream-aquifer exchanges and better assess the associated aquifer responses that are often impacted by the magnitude and the frequency of the river stage fluctuations. The study focuses on the Oise basin (17 000 km2, part of the 65 000 km2 Seine basin in Northern France) where stream-aquifer exchanges cannot be assessed directly by experimental methods. Nowadays numerical methods are the most appropriate approaches for assessing stream-aquifer exchanges at this scale. A regional distributed process-based hydro(geo)logical model, Eau-Dyssée, is used, which aims at the integrated modeling of the hydrosystem to manage the various elements involved in the quantitative and qualitative aspects of water resources. Eau-Dyssée simulates pseudo 3D flow in aquifer systems solving the diffusivity equation with a finite difference numerical scheme. River flow is simulated with a Muskingum model. In addition to the in-stream discharge, a river stage estimate is needed to calculate the water exchange at the stream-aquifer interface using the Darcy law. Three methods for assessing in-stream river stages are explored to determine the most appropriate representation at regional scale over 25 years (1980-2005). The first method consists in defining rating curves for each cell of a 1D Saint-Venant hydraulic model. The second method consists in interpolating observed rating curves (at gauging stations) onto the river cells of the hydro(geo)logical model. The interpolation technique is based on geostatistics. The last method assesses river stage using Manning equation with a simplified rectangular cross-section (water depth equals the hydraulic radius). Compared to observations, the geostatistical and the Manning methodologies lead to slightly less accurate (but still acceptable) results offering a low computational cost opportunity

  10. Pre-ABoVE: Arctic Alaska Vegetation, Geobotanical, Physiographic Data, 1993-2005

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides the spatial distributions of vegetation types, geobotanical characteristics, and physiographic features for the Arctic tundra region of Alaska...

  11. Simulation of regional temperature change effect of land cover change in agroforestry ecotone of Nenjiang River Basin in China

    Science.gov (United States)

    Liu, Tingxiang; Zhang, Shuwen; Yu, Lingxue; Bu, Kun; Yang, Jiuchun; Chang, Liping

    2017-05-01

    The Northeast China is one of typical regions experiencing intensive human activities within short time worldwide. Particularly, as the significant changes of agriculture land and forest, typical characteristics of pattern and process of agroforestry ecotone change formed in recent decades. The intensive land use change of agroforestry ecotone has made significant change for regional land cover, which had significant impact on the regional climate system elements and the interactions among them. This paper took agroforestry ecotone of Nenjiang River Basin in China as study region and simulated temperature change based on land cover change from 1950s to 1978 and from 1978 to 2010. The analysis of temperature difference sensitivity to land cover change based on Weather Research and Forecasting (WRF) model showed that the land cover change from 1950s to 1978 induced warming effect over all the study area, including the change of grassland to agriculture land, grassland to deciduous broad-leaved forest, and deciduous broad-leaved forest to shrub land. The land cover change from 1978 to 2010 induced cooling effect over all the study area, including the change of deciduous broad-leaved forest to agriculture land, grassland to agriculture land, shrub land to agriculture land, and deciduous broad-leaved forest to grassland. In addition, the warming and cooling effect of land cover change was more significant in the region scale than specific land cover change area.

  12. Occurrence and transport of 17 perfluoroalkyl acids in 12 coastal rivers in south Bohai coastal region of China with concentrated fluoropolymer facilities

    International Nuclear Information System (INIS)

    Wang, Pei; Lu, Yonglong; Wang, Tieyu; Fu, Yaning; Zhu, Zhaoyun; Liu, Shijie; Xie, Shuangwei; Xiao, Yang; Giesy, John P.

    2014-01-01

    Perfluoroalkyl acids (PFAAs) are emerging contaminants that have raised great concern in recent years. While PFAAs manufacturing becomes regulated in developed countries, production has been partly shifted to China. Eight fluoropolymer manufacturing facilities located in the South Bohai coastal region, one of the most populated areas of China, have been used to manufacture PFAA-related substances since 2001. The environmental consequence of the intensive production of PFAAs in this region remains largely unknown. We analyzed 17 PFAAs in twelve coastal rivers of this region, and found staggeringly high concentrations of perfluorooctanoic acid (PFOA) ranging from 0.96 to 4534.41 ng/L. The highest concentration was observed in the Xiaoqing River which received effluents from certain fluoropolymer facilities. Principal component analysis indicated similar sources of several perfluoroalkyl carboxylic acids (PFCAs) in all rivers, which indicated that atmospheric transport, wastewater treatment and surface runoff also acted as important supplements to direct discharge to surface water. - Highlights: • PFAAs were detected in rapidly urbanized regions. • PFOA was found predominant followed by short chain PFCAs. • Fluoropolymer facilities were associated with PFAAs contamination. • Higher PFAAs levels were found near the PTFE production facilities. • Diffusion of PFAAs from rivers to the sea was influenced by tide and current. - High level of PFOA was detected in the river water due to the fluoropolymer industries in South Bohai coastal region

  13. Tourism in rural Alaska

    Science.gov (United States)

    Katrina Church-Chmielowski

    2007-01-01

    Tourism in rural Alaska is an education curriculum with worldwide relevance. Students have started small businesses, obtained employment in the tourism industry and gotten in touch with their people. The Developing Alaska Rural Tourism collaborative project has resulted in student scholarships, workshops on website development, marketing, small...

  14. Renewable Energy in Alaska

    Energy Technology Data Exchange (ETDEWEB)

    2013-03-01

    This report examines the opportunities, challenges, and costs associated with renewable energy implementation in Alaska and provides strategies that position Alaska's accumulating knowledge in renewable energy development for export to the rapidly growing energy/electric markets of the developing world.

  15. Alaska Administrative Manual

    Science.gov (United States)

    Search the Division of Finance site DOF State of Alaska Finance Home Content Area Accounting Charge Cards Division of Finance is to provide accounting, payroll, and travel services for State government Top Department of Administration logo Alaska Department of Administration Division of Finance Search

  16. LearnAlaska Portal

    Science.gov (United States)

    Search the Division of Finance site DOF State of Alaska Finance Home Content Area Accounting Charge Cards Mission Statement The mission of the Division of Finance is to provide accounting, payroll, and travel Top Department of Administration logo Alaska Department of Administration Division of Finance Search

  17. Floristic and structural status of forests in permanent preservation areas of Moju river basin, Amazon region.

    Science.gov (United States)

    Oliveira, J C; Vieira, I C G; Almeida, A S; Silva, C A

    2016-01-01

    The goal of this study is to analyze the floristic patterns and the structure of disturbed and undisturbed upland forests, in Permanent Preservation Areas (PPAs) along the Moju river, in the Brazilian state of Pará. Trees with a diameter equal to or larger than 10cm at 1.30m from the ground (DBH) ≥10cm were analyzed for the upper stratum. For the middle stratum, individuals with DBH between 4.99 and 9.99cm were sampled. Forty-five families and 221 species were found in disturbed forests, and 43 families and 208 species in undisturbed forests. Floristic similarity was high between strata and between forest types, with values above 50%. Similarity was highest between middle strata. The most species-abundant families in undisturbed forests were Fabaceae, Sapotaceae, Chrysobalanaceae and Myrtaceae; the species with the highest density there were Eschweilera grandiflora, Licania sclerophylla and Zygia cauliflora. In disturbed forests, the dominant families were Fabaceae, Sapotaceae, Lecythidaceae and Melastomataceae. The Shannon-Wiener diversity index was 3.21 for undisturbed forests and 2.85 for disturbed forests. Non-metric multidimensional scaling (MDS) analysis did not group the forests by their floristic composition in both upper and middle strata. Overall, the PPA forests along the Moju river, even if disturbed, did not show major floristic changes but substantially change their structural characteristics.

  18. Floristic and structural status of forests in permanent preservation areas of Moju river basin, Amazon region

    Directory of Open Access Journals (Sweden)

    J. C. Oliveira

    Full Text Available Abstract The goal of this study is to analyze the floristic patterns and the structure of disturbed and undisturbed upland forests, in Permanent Preservation Areas (PPAs along the Moju river, in the Brazilian state of Pará. Trees with a diameter equal to or larger than 10cm at 1.30m from the ground (DBH ≥10cm were analyzed for the upper stratum. For the middle stratum, individuals with DBH between 4.99 and 9.99cm were sampled. Forty-five families and 221 species were found in disturbed forests, and 43 families and 208 species in undisturbed forests. Floristic similarity was high between strata and between forest types, with values above 50%. Similarity was highest between middle strata. The most species-abundant families in undisturbed forests were Fabaceae, Sapotaceae, Chrysobalanaceae and Myrtaceae; the species with the highest density there were Eschweilera grandiflora, Licania sclerophylla and Zygia cauliflora. In disturbed forests, the dominant families were Fabaceae, Sapotaceae, Lecythidaceae and Melastomataceae. The Shannon-Wiener diversity index was 3.21 for undisturbed forests and 2.85 for disturbed forests. Non-metric multidimensional scaling (MDS analysis did not group the forests by their floristic composition in both upper and middle strata. Overall, the PPA forests along the Moju river, even if disturbed, did not show major floristic changes but substantially change their structural characteristics.

  19. Source apportionment and health effect of NO_x over the Pearl River Delta region in southern China

    International Nuclear Information System (INIS)

    Lu, Xingcheng; Yao, Teng; Li, Ying; Fung, Jimmy C.H.; Lau, Alexis K.H.

    2016-01-01

    As one of the most notorious atmospheric pollutants, NO_x not only promotes the formation of ozone but also has adverse health effects on humans. It is therefore of great importance to study the sources of NO_x and its effects on human health. The Comprehensive Air Quality Model (CAMx) modeling system and ozone source apportionment technology (OSAT) were used to study the contribution of NO_x from different emission sources over southern China. The results indicate that heavy duty diesel vehicles (HDDVs) and industrial point sources are the two major local NO_x sources, accounting for 30.8% and 18.5% of local NO_x sources, respectively. In Hong Kong, marine emissions contributed around 43.4% of local NO_x in 2011. Regional transport is another important source of this pollutant, especially in February and November, and it can contribute over 30% of ambient NO_x on average. Power plant point emission is an significant regional source in Zhuhai, Zhongshan and Foshan. The total emission sources are estimated to cause 2119 (0–4405) respiratory deaths and 991 (0–2281) lung cancer deaths due to long-term exposure to NO_x in the Pearl River Delta region. Our results suggest that local governments should combine their efforts and vigorously promote further reduction of NO_x emissions, especially for those sources that make a substantial contribution to NO_x emissions and affect human health: HDDV, LDGV, industrial point sources and marine sources. - Highlights: • WRF-CAMx modeling system with OSAT was used to study the source of NO_x over Pearl River Delta region in China. • The results indicated that local emission and regional transportation are important contributors for NO_x in this region. • Heavy duty diesel vehicle, marine emission and industrial point source are three important contribution sectors. • Long-term exposure to NO_x is estimated to cause 2119 respiratory deaths and 991 lung cancer deaths in PRD during 2011. - Result indicated that heavy duty

  20. Bringing It All Together: The Southeast Alaska Music Festival.

    Science.gov (United States)

    Howey, Brad

    2003-01-01

    Describes the Southeast Alaska Music Festival discussing topics such as the role of the host school, the communities and schools within the region, and scoring procedures at the Festival. Includes a festival schedule. (CMK)

  1. Quantifying the streamflow response to frozen ground degradation in the source region of the Yellow River within the Budyko framework

    Science.gov (United States)

    Wang, Taihua; Yang, Hanbo; Yang, Dawen; Qin, Yue; Wang, Yuhan

    2018-03-01

    The source region of the Yellow River (SRYR) is greatly important for water resources throughout the entire Yellow River Basin. Streamflow in the SRYR has experienced great changes over the past few decades, which is closely related to the frozen ground degradation; however, the extent of this influence is still unclear. In this study, the air freezing index (DDFa) is selected as an indicator for the degree of frozen ground degradation. A water-energy balance equation within the Budyko framework is employed to quantify the streamflow response to the direct impact of climate change, which manifests as changes in the precipitation and potential evapotranspiration, as well as the impact of frozen ground degradation, which can be regarded as part of the indirect impact of climate change. The results show that the direct impact of climate change and the impact of frozen ground degradation can explain 55% and 33%, respectively, of the streamflow decrease for the entire SRYR from Period 1 (1965-1989) to Period 2 (1990-2003). In the permafrost-dominated region upstream of the Jimai hydrological station, the impact of frozen ground degradation can explain 71% of the streamflow decrease. From Period 2 (1990-2003) to Period 3 (2004-2015), the observed streamflow did not increase as much as the precipitation; this could be attributed to the combined effects of increasing potential evapotranspiration and more importantly, frozen ground degradation. Frozen ground degradation could influence streamflow by increasing the groundwater storage when the active layer thickness increases in permafrost-dominated regions. These findings will help develop a better understanding of the impact of frozen ground degradation on water resources in the Tibetan Plateau.

  2. Increasing trends in rainfall-runoff erosivity in the Source Region of the Three Rivers, 1961-2012.

    Science.gov (United States)

    Wang, Yousheng; Cheng, Congcong; Xie, Yun; Liu, Baoyuan; Yin, Shuiqing; Liu, Yingna; Hao, Yanfang

    2017-08-15

    As the head source of the two longest rivers in China and the longest river in Southeast Asia, the East Qinghai-Tibetan Plateau (QTP) is experiencing increasing thaw snowmelt and more heavy precipitation events under global warming, which might lead to soil erosion risk. To understand the potential driving force of soil erosion and its relationship with precipitation in the context of climate change, this study analyzed long-term variations in annual rainfall-runoff erosivity, a climatic index of soil erosion, by using the Mann-Kendall statistical test and Theil and Sen's approach in the Source Region of the Three Rivers during 1961-2012. The results showed the followings: (i) increasing annual rainfall-runoff erosivity was observed over the past 52years, with a mean relative trend index (RT 1 ) value of 12.1%. The increasing trend was more obvious for the latest two decades: RT 1 was nearly three times larger than that over the entire period; (ii) more precipitation events and a higher precipitation amount were the major forces for the increasing rainfall-runoff erosivity; (iii) similar rising trends in sediment yields, which corresponded to rainfall-runoff erosivity under slightly increasing vegetation coverage in the study area, implied a large contribution of rainfall-runoff erosivity to the increasing sediment yields; and (iv) high warming rates increased the risk of soil destruction, soil erosion and sediment yields. Conservation measures, such as enclosing grassland, returning grazing land to grassland and rotation grazing since the 1980s, have maintained vegetation coverage and should be continued and strengthened. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. An Agent-Based Reasoning of Impacts of Regional Climate Changes on Land Use Changes in the Three-River Headwaters Region of China

    Directory of Open Access Journals (Sweden)

    Tao Zhang

    2013-01-01

    Full Text Available The land surface in Three-River Headwaters Region (TRHR, a typical ecological fragile zone of China, is quite sensitive to the climate changes which will destabilize certain ecosystem services valuable to the entire nation and neighboring countries. This study aimed to analyze the impacts of climate changes and agents’ adaptive behaviors on the regional land use changes with the agent based model (ABM. First, the main agents were extracted according to the production resources endowments and socioeconomic background. Then the agents’ land use behaviors were analyzed and parameterized. Thereafter, the ABM model was built to simulate the impacts of the climate changes on the regional land use changes and agents’ economic benefits. The results showed that the land use changes were mainly characterized by the increase of grassland and decrease of unused land area. Besides, the agents would get more wealth under the scenario without climate changes in the long term, even though the total income is lower than that under the scenario with climate changes. In addition, the sensitivity analysis indicated that the model is sensitive to the climatic conditions, market price of agricultural and animal husbandry products, government subsidies, and cost control.

  4. A comparative study of artificial neural network, adaptive neuro fuzzy inference system and support vector machine for forecasting river flow in the semiarid mountain region

    Science.gov (United States)

    He, Zhibin; Wen, Xiaohu; Liu, Hu; Du, Jun

    2014-02-01

    Data driven models are very useful for river flow forecasting when the underlying physical relationships are not fully understand, but it is not clear whether these data driven models still have a good performance in the small river basin of semiarid mountain regions where have complicated topography. In this study, the potential of three different data driven methods, artificial neural network (ANN), adaptive neuro fuzzy inference system (ANFIS) and support vector machine (SVM) were used for forecasting river flow in the semiarid mountain region, northwestern China. The models analyzed different combinations of antecedent river flow values and the appropriate input vector has been selected based on the analysis of residuals. The performance of the ANN, ANFIS and SVM models in training and validation sets are compared with the observed data. The model which consists of three antecedent values of flow has been selected as the best fit model for river flow forecasting. To get more accurate evaluation of the results of ANN, ANFIS and SVM models, the four quantitative standard statistical performance evaluation measures, the coefficient of correlation (R), root mean squared error (RMSE), Nash-Sutcliffe efficiency coefficient (NS) and mean absolute relative error (MARE), were employed to evaluate the performances of various models developed. The results indicate that the performance obtained by ANN, ANFIS and SVM in terms of different evaluation criteria during the training and validation period does not vary substantially; the performance of the ANN, ANFIS and SVM models in river flow forecasting was satisfactory. A detailed comparison of the overall performance indicated that the SVM model performed better than ANN and ANFIS in river flow forecasting for the validation data sets. The results also suggest that ANN, ANFIS and SVM method can be successfully applied to establish river flow with complicated topography forecasting models in the semiarid mountain regions.

  5. City-specific vehicle emission control strategies to achieve stringent emission reduction targets in China's Yangtze River Delta region.

    Science.gov (United States)

    Zhang, Shaojun; Wu, Ye; Zhao, Bin; Wu, Xiaomeng; Shu, Jiawei; Hao, Jiming

    2017-01-01

    The Yangtze River Delta (YRD) region is one of the most prosperous and densely populated regions in China and is facing tremendous pressure to mitigate vehicle emissions and improve air quality. Our assessment has revealed that mitigating vehicle emissions of NOx would be more difficult than reducing the emissions of other major vehicular pollutants (e.g., CO, HC and PM 2.5 ) in the YRD region. Even in Shanghai, where the emission control implemented are more stringent than in Jiangsu and Zhejiang, we observed little to no reduction in NOx emissions from 2000 to 2010. Emission-reduction targets for HC, NOx and PM 2.5 are determined using a response surface modeling tool for better air quality. We design city-specific emission control strategies for three vehicle-populated cities in the YRD region: Shanghai and Nanjing and Wuxi in Jiangsu. Our results indicate that even if stringent emission control consisting of the Euro 6/VI standards, the limitation of vehicle population and usage, and the scrappage of older vehicles is applied, Nanjing and Wuxi will not be able to meet the NOx emissions target by 2020. Therefore, additional control measures are proposed for Nanjing and Wuxi to further mitigate NOx emissions from heavy-duty diesel vehicles. Copyright © 2016. Published by Elsevier B.V.

  6. Variation of Runoff and Precipitation in the Hekou-Longmen Region of the Yellow River Based on Elasticity Analysis

    Directory of Open Access Journals (Sweden)

    Erhui Li

    2014-01-01

    Full Text Available Precipitation is very important to the formation of runoff, and studying of runoff variation and its response to precipitation has practical significance to sustainable utilization of water resources. The study used Mann-Kendall test, anomaly accumulation method, and precipitation elasticity of runoff method to analyze the changes in the relation of precipitation and runoff and the contribution of precipitation to runoff change in the Hekou-Longmen region (from 1957 to 2010, Huangfuchuan watershed (from 1954 to 2010, and Yanhe watershed (from 1952 to 2010 in the middle reaches of the Yellow River. The results showed that runoff appeared a significant decreasing trend (P=0.01 while it was not significant in precipitation in all study areas. In particular, the reductions of average annual runoff in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed were 72.7%, 87.5%, and 32.2%, respectively, during 2000–2010 compared to the 1950s. There existed two abrupt change points of the runoff in the Hekou-Longmen region and Huangfuchuan watershed, which were detected in 1979 and 1998. But in the Yanhe watershed only one abrupt change point was found in 1996. The precipitation elasticities of runoff were 1.11, 1.09, and 1.26, respectively, and the contributions of precipitation on runoff reduction were 26.4%, 17.9%, and 31.6%, respectively, in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed.

  7. Variation of Runoff and Precipitation in the Hekou-Longmen Region of the Yellow River Based on Elasticity Analysis

    Science.gov (United States)

    Li, Erhui; Mu, Xingmin; Zhao, Guangju; Gao, Peng; Shao, Hongbo

    2014-01-01

    Precipitation is very important to the formation of runoff, and studying of runoff variation and its response to precipitation has practical significance to sustainable utilization of water resources. The study used Mann-Kendall test, anomaly accumulation method, and precipitation elasticity of runoff method to analyze the changes in the relation of precipitation and runoff and the contribution of precipitation to runoff change in the Hekou-Longmen region (from 1957 to 2010), Huangfuchuan watershed (from 1954 to 2010), and Yanhe watershed (from 1952 to 2010) in the middle reaches of the Yellow River. The results showed that runoff appeared a significant decreasing trend (P = 0.01) while it was not significant in precipitation in all study areas. In particular, the reductions of average annual runoff in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed were 72.7%, 87.5%, and 32.2%, respectively, during 2000–2010 compared to the 1950s. There existed two abrupt change points of the runoff in the Hekou-Longmen region and Huangfuchuan watershed, which were detected in 1979 and 1998. But in the Yanhe watershed only one abrupt change point was found in 1996. The precipitation elasticities of runoff were 1.11, 1.09, and 1.26, respectively, and the contributions of precipitation on runoff reduction were 26.4%, 17.9%, and 31.6%, respectively, in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed. PMID:24955424

  8. Variation of runoff and precipitation in the Hekou-Longmen region of the Yellow River based on elasticity analysis.

    Science.gov (United States)

    Li, Erhui; Mu, Xingmin; Zhao, Guangju; Gao, Peng; Shao, Hongbo

    2014-01-01

    Precipitation is very important to the formation of runoff, and studying of runoff variation and its response to precipitation has practical significance to sustainable utilization of water resources. The study used Mann-Kendall test, anomaly accumulation method, and precipitation elasticity of runoff method to analyze the changes in the relation of precipitation and runoff and the contribution of precipitation to runoff change in the Hekou-Longmen region (from 1957 to 2010), Huangfuchuan watershed (from 1954 to 2010), and Yanhe watershed (from 1952 to 2010) in the middle reaches of the Yellow River. The results showed that runoff appeared a significant decreasing trend (P = 0.01) while it was not significant in precipitation in all study areas. In particular, the reductions of average annual runoff in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed were 72.7%, 87.5%, and 32.2%, respectively, during 2000-2010 compared to the 1950s. There existed two abrupt change points of the runoff in the Hekou-Longmen region and Huangfuchuan watershed, which were detected in 1979 and 1998. But in the Yanhe watershed only one abrupt change point was found in 1996. The precipitation elasticities of runoff were 1.11, 1.09, and 1.26, respectively, and the contributions of precipitation on runoff reduction were 26.4%, 17.9%, and 31.6%, respectively, in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed.

  9. Assessment of transboundary environmental effects in the Pearl River Delta Region: Is there a role for strategic environmental assessment?

    International Nuclear Information System (INIS)

    Marsden, Simon

    2011-01-01

    China's EIA Law does not require transboundary proposals to be assessed, despite recognition of this globally, for example in the Espoo Convention and Kiev Protocol, and in the European EIA and SEA Directives. In a transboundary context assessment within a state is unusual, as regulating these effects is primarily about the relationship between states. However where a state has more than one legal system such as in the Pearl River Delta (PRD) Region of southern China, transboundary effects should also be addressed. Yet despite the geographical connections between Guangdong Province in mainland China (where the EIA Law applies) and the Hong Kong and Macau Special Administrative Regions (which have their own provisions, neither of which requires transboundary assessments), EIA and SEA are carried out separately. Coordinated or joint approaches to transboundary assessment are generally absent, with the legal autonomy of Hong Kong and Macau a major constraint. As a result institutional responses at the policy level have developed. The article considers global experiences with regulating transboundary EIA and SEA, and analyses potential application to land use, transport and air and water planning in the PRD Region. If applied, benefits may include prevention or mitigation of cumulative effects, broader public participation, and improvements to environmental governance. The PRD Region experience may encourage China to conduct and coordinate EIA and SEA processes with neighbouring states, which has been non-existent or extremely limited to date.

  10. [Process of land use transition and its impact on regional ecological quality in the Middle Reaches of Heihe River, China].

    Science.gov (United States)

    Wang, Fu Hong; Zhao, Rui Feng; Zhang, Li Hua; Li, Hong Wei

    2017-12-01

    Land use transition is one of the main drivers of regional ecosystem change in arid area, which directly affects human well-being. Based on the satellite images of 1987, 2001 and 2016, the change detection assessment model and ecological response model were used to analyze the process of land use transition and response of ecological quality during 1987-2016 in the ecologically fragile middle reaches of the Heihe River. The results showed that the land use change was significant during 1987-2016 and the total change increased significantly, as well as the continuous increase of the cultivated land and construction land. There was a strong tendency of transform from grassland to cultivated land, while the tendency of transforming unused land to other land classes was not strong under a random process of gain or loss. During 1987-2016, the ecological quality of the study area displayed a decreasing trend as a whole and the ecological land decreased by 2.8%. The land use transition with the greatest impact on the ecological environment degradation was the transition of the grassland to the cultivated land and unused land. Therefore, in order to promote the sustainable use of regional land resources and to improve the regional ecological quality, it is necessary to allocate the proportion of production land and ecological land according to the regional water resources.

  11. Regional water table (2016) in the Mojave River and Morongo groundwater basins, southwestern Mojave Desert, California

    Science.gov (United States)

    Dick, Meghan; Kjos, Adam

    2017-12-07

    From January to April 2016, the U.S. Geological Survey (USGS), the Mojave Water Agency, and other local water districts made approximately 1,200 water-level measurements in about 645 wells located within 15 separate groundwater basins, collectively referred to as the Mojave River and Morongo groundwater basins. These data document recent conditions and, when compared with older data, changes in groundwater levels. A water-level contour map was drawn using data measured in 2016 that shows the elevation of the water table and general direction of groundwater movement for most of the groundwater basins. Historical water-level data stored in the USGS National Water Information System (https://waterdata.usgs.gov/nwis/) database were used in conjunction with data collected for this study to construct 37 hydrographs to show long-term (1930–2016) and short-term (1990–2016) water-level changes in the study area.

  12. SECURITY RISKS, MYTHS IN A TRANSITIONING SUB-NATIONAL REGIONAL ECONOMY (CROSS RIVER STATE AND IMAGINATIVE GEOGRAPHIES OF NIGERIA

    Directory of Open Access Journals (Sweden)

    J. K. UKWAYI

    2015-03-01

    Full Text Available The emergence of an “international community” through accumulation of perceived risks that contrasts with those risks (of considerably lower levels of seriousness compared to those perceived constitutes one of the interesting (or intriguing subjects of risks and disaster studies surrounding the 9/11 era. The constructions of “imaginative geographies”, have frequently been biased in the practices that underlie the mapping of the foreign places tend to put-down the affected regions in their “paintings” for the global community. The latter are subsequently “demonized” in their ratings of competence for participating in world trade, tourism, travel, among other social/cultural, and economic and political activities. The objective of this article is to highlight how the exaggeration of risks (contrasted to actually existing/lived risks, practices that are frequently associated with such adverse “imaginative geographies” poses sub-national regional development dilemma in Nigeria’s Niger Delta. We trace the roots of adverse “imaginative geographies” of Nigeria to the Abacha dictatorship (1993-1997. Then we highlight the mixed characteristics of the Niger Delta conditions during the “return of positive image recapture” by Nigeria’s federal government (re-democratisation of the Fourth Republic, 1999-present, re-branding campaigns; as well as adverse conditions present. Most significantly, we show that despite these adversities, a combination of favorable geographical size, differentiation, sub-national regional security programme formulation and management taking aims at diversification have created “large oases” of peace and security in Cross River State, a part of the Niger Delta that has been completely unscathed by insurgencies of the nearby sub-national region and further away national origin. Apart from identifying sub-national regions qualifying for delisting from “adverse imaginative geographies” due to

  13. Distribution of polycyclic aromatic hydrocarbons in thirty typical soil profiles in the Yangtze River Delta region, east China

    International Nuclear Information System (INIS)

    Ping, L.F.; Luo, Y.M.; Zhang, H.B.; Li, Q.B.; Wu, L.H.

    2007-01-01

    Polycyclic aromatic hydrocarbons (PAHs) were quantified in 30 soil profiles from the Yangtze River Delta Region, in east China. Relative concentrations of PAH compounds with different benzene rings and ratios of fluoranthene to fluoranthene plus pyrene and benz(a)anthracene to benz(a)anthracene plus chrysene were used to identify the possible sources of soil PAHs. Total concentrations of 15 PAHs in topsoils ranged from 8.6 to 3881 μg kg -1 with an average of 397 μg kg -1 . Half of the soil samples were considered to be contaminated with PAHs (>200 μg kg -1 ) and two sampling sites were heavily polluted by PAHs with concentrations >1000 μg kg -1 . Phenanthrene was found in soils below a depth of 100 cm in half of the sampling sites, but the detectable ratio of benzo(a)pyrene decreased sharply from 100% in topsoil to 0 in the 4th horizon. - The information was provided on levels, distributions, and possible sources of PAHs in the soils of Yangtze River Delta area

  14. Regional evapotranspiration estimation based on a two-layer remote-sensing scheme in Shahe River basin

    International Nuclear Information System (INIS)

    Yin, Jian; Wang, Huixiao

    2014-01-01

    Land surface evapotranspiration (ET) derived from remote sensing data has significant meaning for plant growth monitoring, crop yield assessment, disaster monitoring and understanding energy and water cycle in river basin area and surrounding regions. In the study, we developed a land surface ET remote sensing retrieval system to estimate the daily ET in Shahe river basin using the TM/ETM+ images. The system is based on the two-layer ET model and includes three parts: inversion of the evaporation ration using two-layer model, calculation of total daily net radiation, and estimation of daily ET based on evaporation fraction method. The results show that the average daily ET is about 2.28mm of the typical days in spring, and 2.97mm in summer, 1.59mm in autumn, and 0.5mm in winter. The ET in upstream areas covered by forest is higher than that in the downstream covered by settlement and farmland. In summer the difference of ET between the upper reaches and lower reaches is smaller compared to the other three seasons. The measurements by large aperture scintillometer and eddy correlation instrument were used for validation. By comparing the observed data with the estimated data, we found the estimation system had a high precision with the relative error between 0 and 16% (mean error of 11.1%), and the variance 0.77mm

  15. Integrative taxonomy supports new candidate fish species in a poorly studied neotropical region: the Jequitinhonha River Basin.

    Science.gov (United States)

    Pugedo, Marina Lages; de Andrade Neto, Francisco Ricardo; Pessali, Tiago Casarim; Birindelli, José Luís Olivan; Carvalho, Daniel Cardoso

    2016-06-01

    Molecular identification through DNA barcoding has been proposed as a way to standardize a global biodiversity identification system using a partial sequence of the mitochondrial COI gene. We applied an integrative approach using DNA barcoding and traditional morphology-based bioassessment to identify fish from a neotropical region possessing low taxonomic knowledge: the Jequitinhonha River Basin (Southeastern Brazil). The Jequitinhonha River Basin (JRB) has a high rate of endemism and is considered an area of high priority for fish conservation, with estimates indicating the presence of around 110 native and non-indigenous species. DNA barcodes were obtained from 260 individuals belonging to 52 species distributed among 35 genera, 21 families and 6 orders, including threatened and rare species such as Rhamdia jequitinhonha and Steindachneridion amblyurum. The mean Kimura two-parameter genetic distances within species, genera and families were: 0.44, 12.16 and 20.58 %, respectively. Mean intraspecific genetic variation ranged from 0 to 11.43 %, and high values (>2 %) were recovered for five species. Species with a deep intraspecific distance, possibly flagging overlooked taxa, were detected within the genus Pimelodella. Fifteen species, only identified to the genus level, had unique BINs, with a nearest neighbor distance over 2 % and therefore, potential new candidate species supported by DNA barcoding. The integrative taxonomy approach using DNA barcoding and traditional taxonomy may be a remedy to taxonomy impediment, accelerating species identification by flagging potential new candidate species and to adequately conserve the megadiverse neotropical ichthyofauna.

  16. Assessment of climate change impact on hydrological extremes in two source regions of the Nile River Basin

    Directory of Open Access Journals (Sweden)

    M. T. Taye

    2011-01-01

    Full Text Available The potential impact of climate change was investigated on the hydrological extremes of Nyando River and Lake Tana catchments, which are located in two source regions of the Nile River basin. Climate change scenarios were developed for rainfall and potential evapotranspiration (ETo, considering 17 General Circulation Model (GCM simulations to better understand the range of possible future change. They were constructed by transferring the extracted climate change signals to the observed series using a frequency perturbation downscaling approach, which accounts for the changes in rainfall extremes. Projected changes under two future SRES emission scenarios A1B and B1 for the 2050s were considered. Two conceptual hydrological models were calibrated and used for the impact assessment. Their difference in simulating the flows under future climate scenarios was also investigated.

    The results reveal increasing mean runoff and extreme peak flows for Nyando catchment for the 2050s while unclear trend is observed for Lake Tana catchment for mean volumes and high/low flows. The hydrological models for Lake Tana catchment, however, performed better in simulating the hydrological regimes than for Nyando, which obviously also induces a difference in the reliability of the extreme future projections for both catchments. The unclear impact result for Lake Tana catchment implies that the GCM uncertainty is more important for explaining the unclear trend than the hydrological models uncertainty. Nevertheless, to have a better understanding of future impact, hydrological models need to be verified for their credibility of simulating extreme flows.

  17. Symposium Proceedings: Tapping into natural gas production and infrastructure opportunities in the Alaska North Slope, Mackenzie Delta and Beaufort Sea Regions

    International Nuclear Information System (INIS)

    2001-01-01

    This Symposium was organized by the Canadian Institute to bring together stakeholders and other interested parties from governments, industry and the investment community to discuss the resource and development potential of Arctic natural gas fields, and related investment and regulatory matters. Various pipeline route alternatives, Aboriginal perspectives on development of natural resources, differences in regulatory regimes, and the need to consider the social and cultural aspects of development also received full exposure. Other than welcoming addresses by political leaders of the two territories and of the State of Alaska, discussions were informal, hence the text of presentations is not available. Nevertheless, the speaking notes and viewgraphs included in this volume, are good indicators of the range of topics and the depth and nature of the discussions which took place

  18. A Decade of Shear-Wave Splitting Observations in Alaska

    Science.gov (United States)

    Bellesiles, A. K.; Christensen, D. H.; Abers, G. A.; Hansen, R. A.; Pavlis, G. L.; Song, X.

    2010-12-01

    Over the last decade four PASSCAL experiments have been conducted in different regions of Alaska. ARCTIC, BEAAR and MOOS form a north-south transect across the state, from the Arctic Ocean to Price Williams Sound, while the STEEP experiment is currently deployed to the east of that line in the St Elias Mountains of Southeastern Alaska. Shear-wave splitting observations from these networks in addition to several permanent stations of the Alaska Earthquake Information Center were determined in an attempt to understand mantle flow under Alaska in a variety of different geologic settings. Results show two dominant splitting patterns in Alaska, separated by the subducted Pacific Plate. North of the subducted Pacific Plate fast directions are parallel to the trench (along strike of the subducted Pacific Plate) indicating large scale mantle flow in the northeast-southwest direction with higher anisotropy (splitting times) within the mantle wedge. Within or below the Pacific Plate fast directions are normal to the trench in the direction of Pacific Plate convergence. In addition to these two prominent splitting patterns there are several regions that do not match either of these trends. These more complex regions which include the results from STEEP could be due to several factors including effects from the edge of the Pacific Plate. The increase of station coverage that Earthscope will bring to Alaska will aid in developing a more complete model for anisotropy and mantle flow in Alaska.

  19. Impact of city effluents on water quality of Indus River: assessment of temporal and spatial variations in the southern region of Khyber Pakhtunkhwa, Pakistan.

    Science.gov (United States)

    Khan, Ilham; Khan, Azim; Khan, Muhammad Sohail; Zafar, Shabnam; Hameed, Asma; Badshah, Shakeel; Rehman, Shafiq Ur; Ullah, Hidayat; Yasmeen, Ghazala

    2018-04-04

    The impact of city effluents on water quality of Indus River was assessed in the southern region of Khyber Pakhtunkhwa, Pakistan. Water samples were collected in dry (DS) and wet (WS) seasons from seven sampling zones along Indus River and the physical, bacteriological, and chemical parameters determining water quality were quantified. There were marked temporal and spatial variations in the water quality of Indus River. The magnitude of pollution was high in WS compared with DS. The quality of water varied across the sampling zones, and it greatly depended upon the nature of effluents entering the river. Water samples exceeded the WHO permissible limits for pH, EC, TDS, TS, TSS, TH, DO, BOD, COD, total coliforms, Escherichia coli, Ca 2+ , Mg 2+ , NO 3 - , and PO 4 2- . Piper analysis indicated that water across the seven sampling zones along Indus River was alkaline in nature. Correlation analyses indicated that EC, TDS, TS, TH, DO, BOD, and COD may be considered as key physical parameters, while Na + , K + , Ca 2+ , Mg 2+ , Cl - , F - , NO 3 - , PO 4 2- , and SO 4 2- as key chemical parameters determining water quality, because they were strongly correlated (r > 0.70) with most of the parameters studied. Cluster analysis indicated that discharge point at Shami Road is the major source of pollution impairing water quality of Indus River. Wastewater treatment plants must be installed at all discharge points along Indus River for protecting the quality of water of this rich freshwater resource in Pakistan.

  20. Simulation of the Regional Ground-Water-Flow System and Ground-Water/Surface-Water Interaction in the Rock River Basin, Wisconsin

    Science.gov (United States)

    Juckem, Paul F.

    2009-01-01

    A regional, two-dimensional, areal ground-water-flow model was developed to simulate the ground-water-flow system and ground-water/surface-water interaction in the Rock River Basin. The model was developed by the U.S. Geological Survey (USGS), in cooperation with the Rock River Coalition. The objectives of the regional model were to improve understanding of the ground-water-flow system and to develop a tool suitable for evaluating the effects of potential regional water-management programs. The computer code GFLOW was used because of the ease with which the model can simulate ground-water/surface-water interactions, provide a framework for simulating regional ground-water-flow systems, and be refined in a stepwise fashion to incorporate new data and simulate ground-water-flow patterns at multiple scales. The ground-water-flow model described in this report simulates the major hydrogeologic features of the modeled area, including bedrock and surficial aquifers, ground-water/surface-water interactions, and ground-water withdrawals from high-capacity wells. The steady-state model treats the ground-water-flow system as a single layer with hydraulic conductivity and base elevation zones that reflect the distribution of lithologic groups above the Precambrian bedrock and a regionally significant confining unit, the Maquoketa Formation. In the eastern part of the Basin where the shale-rich Maquoketa Formation is present, deep ground-water flow in the sandstone aquifer below the Maquoketa Formation was not simulated directly, but flow into this aquifer was incorporated into the GFLOW model from previous work in southeastern Wisconsin. Recharge was constrained primarily by stream base-flow estimates and was applied uniformly within zones guided by regional infiltration estimates for soils. The model includes average ground-water withdrawals from 1997 to 2006 for municipal wells and from 1997 to 2005 for high-capacity irrigation, industrial, and commercial wells. In addition

  1. Accumulation, transfer, and environmental risk of soil mercury in a rapidly industrializing region of the Yangtze River Delta, China

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Biao; Yan, Lianxiang; Sun, Weixia; Zhao, Yongcun; Shi, Xuezheng [Chinese Academy of Sciences, Nanjing (China). State Key Lab. of Soil and Sustainable Agriculture; Wang, Mei [Chinese Academy of Sciences, Nanjing (China). State Key Lab. of Soil and Sustainable Agriculture; Graduate Univ. of the Chinese Academy of Sciences, Beijing (China); Weindorf, David C. [Louisiana State Univ., Baton Rouge, LA (United States). AgCenter

    2011-06-15

    Purpose: Mercury (Hg) accumulation and transfer in soil ecosystems has been altered on local, regional, and even global scales, and their environmental risk has increasingly been a concern to the public and the scientific community. Materials and methods: A county level region in Zhangjiagang County, the Yangtze River Delta (YRD) region of China and a factory with Hg-contaminated wastewater discharging within the region were selected to study the accumulation, bioavailability, and transfer of Hg from different sources in soils and crops under rapid industrialization, urbanization, and intensive agricultural activities. Regional soil samples close to and away from factories and local soil and crop samples around a typical factory were collected in the YRD region of China. Soil and crop Hg and basic soil properties were examined. Results and discussion: Significant soil Hg accumulation was found in soils away from factories regardless of Cambosols (Entisols) and Anthrosols (Inceptisols), while the mobile HCl-extractable Hg (HCl-Hg) were greater in soils closer to factories due to a decrease and increase in soil pH and organic matter. A high level of soil total Hg (T-Hg) was found around the factory, and soil and crop Hg accumulation in the vicinity of the factory was localized with an exponential decrease as distance away from the wastewater discharge outlet increased. Although Hg accumulated in these soils, the T-Hg levels at only a few sampling sites in acidic Anthrosols area were found to exceed the second most stringent critical value of Chinese Environmental Quality Standards for Soils. Conclusions: Considering the cessation of Hg-containing agrochemicals and limitation of effects of industrial activities on Hg accumulation, more attention should be paid to the changes in soil properties and crop rotations than controlling the pathways of Hg entering soils because the current environmental risk is mobilization of accumulated soil Hg. (orig.)

  2. Alpine grassland soil organic carbon stock and its uncertainty in the three rivers source region of the Tibetan Plateau.

    Directory of Open Access Journals (Sweden)

    Xiaofeng Chang

    Full Text Available Alpine grassland of the Tibetan Plateau is an important component of global soil organic carbon (SOC stocks, but insufficient field observations and large spatial heterogeneity leads to great uncertainty in their estimation. In the Three Rivers Source Region (TRSR, alpine grasslands account for more than 75% of the total area. However, the regional carbon (C stock estimate and their uncertainty have seldom been tested. Here we quantified the regional SOC stock and its uncertainty using 298 soil profiles surveyed from 35 sites across the TRSR during 2006-2008. We showed that the upper soil (0-30 cm depth in alpine grasslands of the TRSR stores 2.03 Pg C, with a 95% confidence interval ranging from 1.25 to 2.81 Pg C. Alpine meadow soils comprised 73% (i.e. 1.48 Pg C of the regional SOC estimate, but had the greatest uncertainty at 51%. The statistical power to detect a deviation of 10% uncertainty in grassland C stock was less than 0.50. The required sample size to detect this deviation at a power of 90% was about 6-7 times more than the number of sample sites surveyed. Comparison of our observed SOC density with the corresponding values from the dataset of Yang et al. indicates that these two datasets are comparable. The combined dataset did not reduce the uncertainty in the estimate of the regional grassland soil C stock. This result could be mainly explained by the underrepresentation of sampling sites in large areas with poor accessibility. Further research to improve the regional SOC stock estimate should optimize sampling strategy by considering the number of samples and their spatial distribution.

  3. Investigating the Impacts of Landuse-landcover (LULC Change in the Pearl River Delta Region on Water Quality in the Pearl River Estuary and Hong Kong’s Coast

    Directory of Open Access Journals (Sweden)

    Hongyan Xi

    2009-11-01

    Full Text Available Water quality information in the coastal region of Hong Kong and the Pearl River Estuary (PRE is of great concern to the local community. Due to great landuse-landcover (LULC changes with rapid industrialization and urbanization in the Pearl River Delta (PRD region, water quality in the PRE has worsened during the last 20 years. Frequent red tide and harmful algal blooms have occurred in the estuary and its adjacent coastal waters since the 1980s and have caused important economic losses, also possibly threatening to the coastal environment, fishery, and public health in Hong Kong. In addition, recent literature shows that water nutrients in Victoria Harbor of Hong Kong have been proven to be strongly influenced by both the Pearl River and sewage effluent in the wet season (May to September, but it is still unclear how the PRE diluted water intrudes into Victoria Harbor. Due to the cloudy and rainy conditions in the wet season in Hong Kong, ASAR images will be used to monitor the PRE river plumes and track the intruding routes of PRE water nutrients. In this paper, we first review LULC change in the PRD and then show our preliminary results to analyze water quality spatial and temporal information from remote observations with different sensors in the coastal region and estuary. The study will also emphasizes on time series of analysis of LULC trends related to annual sediment yields and critical source areas of erosion for the PRD region since the 1980s.

  4. The presence of Praomys, Lophuromys, and Deomys species (Muridae, Mammalia) in the forest blocks separated by the Congo River and its tributaries (Kisangani region, Democratic Republic of Congo)

    DEFF Research Database (Denmark)

    Katuala, Pionus G B; Kennis, Jan; Nicolas, Violaine

    2008-01-01

    Praomys (four species), Lophuromys (four) and Deomys (one) are among the most common Muridae in the Kisangani region. To establish whether or not rivers constitute dispersal barriers for these rodents, we investigated the presence of these genera and their species in eight localities that are eit......Praomys (four species), Lophuromys (four) and Deomys (one) are among the most common Muridae in the Kisangani region. To establish whether or not rivers constitute dispersal barriers for these rodents, we investigated the presence of these genera and their species in eight localities...

  5. Report on airborne radioactivity surveys and the uranium deposits in the Red River region of Texas and Oklahoma

    International Nuclear Information System (INIS)

    Blair, R.G.; Stehle, F.T.; Levich, R.A.

    1973-11-01

    The U. S. Atomic Energy Commission conducted an airborne radioactivity survey of the Red River region of Texas and Oklahoma beginning in December 1955 and ending in May 1956. All or parts of Archer, Clay, and Montague Counties in northern Texas and Carter, Cotton, Jefferson, and Stephens Counties in southern Oklahoma were surveyed. Particular attention was paid to those areas where exposures are found of red beds of the Permian Wichita Group. Field examinations were conducted of anomalies discovered by airborne reconnaissance as well as those reported by private individuals. Forty localities were examined, the majority in sandstones, siltstones, or conglomerates. Uranium and copper minerals were identified at several localities. Ferruginous staining, bleaching of the sandstone color, calcium carbonate cement, and carbonized plant remains are common to the deposits

  6. Environmental changes and human work in the region of the Upper Paraná River floodplain: processes and interactions

    Directory of Open Access Journals (Sweden)

    EA. Tomanik

    Full Text Available The environment and society constitute a complex of elements and interactions. Thus, an understanding of the processes in which the environment and psychosocial elements are involved may not be gained from knowledge of just one isolated variable. Based on such premises, the present paper, which summarizes the results of a series of studies, adopts work relationships as its main focus, but in addition, it has two complementary objectives. One is to present some analyses on the interaction between human actions and the environmental changes that have been taking place in the region of the Upper Paraná River floodplain and in its boundaries. A secondary aim is to show how those two factors have been changing people's working and living conditions and the identity configuration of some of the human groups that live at that site.

  7. Influence of uranium and thorium in the natural radioactivity in shales from the middle Amazon river region

    International Nuclear Information System (INIS)

    Ferro, A.L.

    1982-02-01

    The feasibility of using the fission track registration technique in the determination of the uranium and thorium content in shales from the middle Amazon river region is studied. The above technique permits, through the determination of the uranium concentration, to establish a correlation between the uranium content and the organic matter present in the shale. In establishing the ratio between the fission tracks due to 238 U and 235 U, the sample was contaminated with natural uranium and analized, so that no modifications on the analysis conditions might change or distort the results. The experimental results were satisfactory and they may contribute to the study of the industrial exploration of these energy sources as well as to the analysis of problems related to environmental control. (Author) [pt

  8. Calcium and magnesium isotope systematics in rivers draining the Himalaya-Tibetan-Plateau region: Lithological or fractionation control?

    Science.gov (United States)

    Tipper, Edward T.; Galy, Albert; Bickle, Mike J.

    2008-02-01

    In rivers draining the Himalaya-Tibetan-Plateau region, the 26Mg/ 24Mg ratio has a range of 2‰ and the 44Ca/ 42Ca ratio has a range of 0.6‰. The average δ26Mg values of tributaries from each of the main lithotectonic units (Tethyan Sedimentary Series (TSS), High Himalayan Crystalline Series (HHCS) and Lesser Himalayan Series (LHS)) are within 2 standard deviation analytical uncertainty (0.14‰). The consistency of average riverine δ26Mg values is in contrast to the main rock types (limestone, dolostone and silicate) which range in their average δ26Mg values by more than 2‰. Tributaries draining the dolostones of the LHS differ in their δ44Ca values compared to tributaries from the TSS and HHCS. The chemistry of these river waters is strongly influenced by dolostone (solute Mg/Ca close to unity) and both δ26Mg (-1.31‰) and δ44Ca (0.64‰) values are within analytical uncertainty of the LHS dolostone. These are the most elevated δ44Ca values in rivers and rock reported so far demonstrating that both riverine and bedrock δ44Ca values may show greater variability than previously thought. Although rivers draining TSS limestone have the lowest δ26Mgandδ44Ca values at -1.41 and 0.42‰, respectively, both are offset to higher values compared to bedrock TSS limestone. The average δ26Mg value of rivers draining mainly silicate rock of the HHCS is -1.25‰, lower by 0.63‰ than the average silicate rock. These differences are consistent with a fractionation of δ26Mg values during silicate weathering. Given that the proportion of Mg exported from the Himalaya as solute Mg is small, the difference in 26Mg/ 24Mg ratios between silicate rock and solute Mg reflects the 26Mg/ 24Mg isotopic fractionation factor ( αsilicate-dissolvedMg) between silicate and dissolved Mg during incongruent silicate weathering. The value of αsilicate-dissolvedMg of 0.99937 implies that in the TSS, solute Mg is primarily derived from silicate weathering, whereas the source of Ca

  9. Cold Lake-Beaver River water management study update: Report of the Cold Lake Regional Water Management Task Force

    International Nuclear Information System (INIS)

    1994-01-01

    The Cold Lake Regional Water Management Task Force was formed in 1992, comprising representatives from local governments, aboriginal groups, the oil industry, and the public. The Task Force's mandate was to advise Alberta Environmental Protection on updating the Cold Lake-Beaver River Water Management Plan, taking into acocunt the views and concerns of the public, industry, and local governments. Industrial water use was found to be the key issue to be addressed in the plan update, so the Task Force focused on reviewing industrial water supply options and developing recommendations on the appropriate water supply to meet long-term requirements. A subcommittee was established to monitor groundwater use by the heavy oil industry. This committee took readings at Imperial Oil's water production and observation wells on a biweekly basis. Nine options for supplying industrial water requirements were examined and evaluated using criteria including supply reliability, economic factors, and impacts on other users and the environment. The Task Force found that the preferred source of water for industrial use is the North Saskatchewan River, to be accessed by a water pipeline. The second and less desirable source of water for industrial use would be a system of weirs on Cold or Primrose Lakes and Wolf Lake, supplemented by the use of brackish water to the maximum extent possible. In the interim, industry was recommended to maximize its use of brackish water and continue to use surface and ground water within existing license limits. Other recommendations were to form provincial or regional boards to oversee water use and issue water licenses, to treat water as a resource, and to establish a fee for industrial use of water. 3 figs., 5 tabs

  10. Using an ensemble of regional climate models to assess climate change impacts on water scarcity in European river basins.

    Science.gov (United States)

    Gampe, David; Nikulin, Grigory; Ludwig, Ralf

    2016-12-15

    Climate change will likely increase pressure on the water balances of Mediterranean basins due to decreasing precipitation and rising temperatures. To overcome the issue of data scarcity the hydrological relevant variables total runoff, surface evaporation, precipitation and air temperature are taken from climate model simulations. The ensemble applied in this study consists of 22 simulations, derived from different combinations of four General Circulation Models (GCMs) forcing different Regional Climate Models (RCMs) and two Representative Concentration Pathways (RCPs) at ~12km horizontal resolution provided through the EURO-CORDEX initiative. Four river basins (Adige, Ebro, Evrotas and Sava) are selected and climate change signals for the future period 2035-2065 as compared to the reference period 1981-2010 are investigated. Decreased runoff and evaporation indicate increased water scarcity over the Ebro and the Evrotas, as well as the southern parts of the Adige and the Sava, resulting from a temperature increase of 1-3° and precipitation decrease of up to 30%. Most severe changes are projected for the summer months indicating further pressure on the river basins already at least partly characterized by flow intermittency. The widely used Falkenmark indicator is presented and confirms this tendency and shows the necessity for spatially distributed analysis and high resolution projections. Related uncertainties are addressed by the means of a variance decomposition and model agreement to determine the robustness of the projections. The study highlights the importance of high resolution climate projections and represents a feasible approach to assess climate impacts on water scarcity also in regions that suffer from data scarcity. Copyright © 2016. Published by Elsevier B.V.

  11. Risk Assessment on Dietary Exposure to Aflatoxin B1 in Post-Harvest Peanuts in the Yangtze River Ecological Region

    Science.gov (United States)

    Ding, Xiaoxia; Wu, Linxia; Li, Peiwu; Zhang, Zhaowei; Zhou, Haiyan; Bai, Yizhen; Chen, Xiaomei; Jiang, Jun

    2015-01-01

    Based on the 2983 peanut samples from 122 counties in six provinces of China’s Yangtze River ecological region collected between 2009–2014, along with the dietary consumption data in Chinese resident nutrition and health survey reports from 2002 and 2004, dietary aflatoxin exposure and percentiles in the corresponding statistics were calculated by non-parametric probability assessment, Monte Carlo simulation and bootstrap sampling methods. Average climatic conditions in the Yangtze River ecological region were calculated based on the data from 118 weather stations via the Thiessen polygon method. The survey results found that the aflatoxin contamination of peanuts was significantly high in 2013. The determination coefficient (R2) of multiple regression reflected by the aflatoxin B1 content with average precipitation and mean temperature in different periods showed that climatic conditions one month before harvest had the strongest impact on aflatoxin B1 contamination, and that Hunan and Jiangxi provinces were greatly influenced. The simulated mean aflatoxin B1 intake from peanuts at the mean peanut consumption level was 0.777–0.790 and 0.343–0.349 ng/(kg·d) for children aged 2–6 and standard adults respectively. Moreover, the evaluated cancer risks were 0.024 and 0.011/(100,000 persons·year) respectively, generally less than China’s current liver cancer incidence of 24.6 cases/(100,000 persons·year). In general, the dietary risk caused by peanut production and harvest was low. Further studies would focus on the impacts of peanut circulation and storage on aflatoxin B1 contamination risk assessment in order to protect peanut consumers’ safety and boost international trade. PMID:26501322

  12. Integrated Studies of a Regional Ozone Pollution Synthetically Affected by Subtropical High and Typhoon System in the Yangtze River Delta Region, China

    Science.gov (United States)

    Xie, M.; Shu, L.

    2017-12-01

    Severe high ozone (O3) episodes usually have close relations to synoptic systems. A regional continuous O3 pollution episode was detected over the Yangtze River Delta (YRD) region in China during August 7-12, 2013, in which the O3 concentrations in more than half of the cities exceeded the national air quality standard. By means of the observational analysis and the WRF/CMAQ numerical simulation, the characteristics and the essential impact factors of the typical regional O3 pollution are investigated. The observational analysis shows that the atmospheric subsidence dominated by Western Pacific subtropical high plays a crucial role in the formation of high-level O3. In addition, when the YRD cities at the front of Typhoon Utor, the periphery circulation of typhoon system can enhance the downward airflows and cause more serious air pollution. But when the typhoon system weakens the subtropical high, the prevailing southeasterly surface wind leads to the mitigation of the O3 pollution. The Integrated Process Rate (IPR) analysis incorporated in CMAQ is applied to further illustrate the combined influence of subtropical high and typhoon system in this O3 episode. The results show that the vertical diffusion (VDIF) and the gas-phase chemistry (CHEM) are two major contributors to O3 formation. On August 10-11, the cities close to the sea are apparently affected by the typhoon system, with the contribution of VDIF increasing to 28.45 ppb/h in Shanghai and 19.76 ppb/h in Hangzhou. When the YRD region is under the control of the typhoon system, the contribution values of all individual processes decrease to a low level in all cities. These results provide an insight for the O3 pollution synthetically impacted by the Western Pacific subtropical high and the tropical cyclone system.

  13. Statistical Seasonal Rainfall Forecast in the Neuquén River Basin (Comahue Region, Argentina

    Directory of Open Access Journals (Sweden)

    Marcela Hebe González

    2015-05-01

    Full Text Available A detailed statistical analysis was performed at the Neuquén river basin using precipitation data for 1980–2007. The hydrological year begins in March with a maximum in June associated with rainfall and another relative maximum in October derived from snow-break. General features of the rainy season and the excess or deficits thereof are analyzed using standardized precipitation index (SPI for a six-month period in the basin. The SPI has a significant cycle of 14.3 years; the most severe excess (SPI greater than 2 has a return period of 25 years, while the most severe droughts (SPI less than −2 have a return period of 10 years. The SPI corresponding to the rainy season (April–September (SPI9 has no significant trend and is used to classify wet/dry years. In order to establish the previous circulation patterns associated with interannual SPI9 variability, the composite fields of wet and dry years are compared. There is a tendency for wet (dry periods to take place during El Niño (La Niña years, when there are positive anomalies of precipitable water over the basin, when the zonal flow over the Pacific Ocean is weakened (intensified and/or when there are negative pressure anomalies in the southern part of the country and Antarctic sea. Some prediction schemes using multiple linear regressions were performed. One of the models derived using the forward stepwise method explained 42% of the SPI9 variance and retained two predictors related to circulation over the Pacific Ocean: one of them shows the relevance of the intensity of zonal flow in mid-latitudes, and the other is because of the influence of low pressure near the Neuquén River basin. The cross-validation used to prove model efficiency showed a correlation of 0.41 between observed and estimated SPI9; there was a probability of detection of wet (dry years of 80% (65% and a false alarm relation of 25% in both cases.

  14. The Impact of the Aerosol Direct Radiative Forcing on Deep Convection and Air Quality in the Pearl River Delta Region

    Science.gov (United States)

    Liu, Z.; Yim, Steve H. L.; Wang, C.; Lau, N. C.

    2018-05-01

    Literature has reported the remarkable aerosol impact on low-level cloud by direct radiative forcing (DRF). Impacts on middle-upper troposphere cloud are not yet fully understood, even though this knowledge is important for regions with a large spatial heterogeneity of emissions and aerosol concentration. We assess the aerosol DRF and its cloud response in June (with strong convection) in Pearl River Delta region for 2008-2012 at cloud-resolving scale using an air quality-climate coupled model. Aerosols suppress deep convection by increasing atmospheric stability leading to less evaporation from the ground. The relative humidity is reduced in middle-upper troposphere due to induced reduction in both evaporation from the ground and upward motion. The cloud reduction offsets 20% of the aerosol DRF. The weaker vertical mixing further increases surface aerosol concentration by up to 2.90 μg/m3. These findings indicate the aerosol DRF impact on deep convection and in turn regional air quality.

  15. Rapid Global River Flood Risk Assessment under Climate and Socioeconomic Scenarios: An Extreme Case of Eurasian region

    Science.gov (United States)

    Kwak, Young-joo; Magome, Jun; Hasegawa, Akira; Iwami, Yoichi

    2017-04-01

    Causing widespread devastation with massive economic damage and loss of human lives, flood disasters hamper economic growth and accelerate poverty particularly in developing countries. Globally, this trend will likely continue due to increase in flood magnitude and lack of preparedness for extreme events. In line with risk reduction efforts since the early 21st century, the monitors and governors of global river floods should pay attention to international scientific and policy communities for support to facilitate evidence-based policy making with a special interest in long-term changes due to climate change and socio-economic effects. Although advanced hydrological inundation models and risk models have been developed to reveal flood risk, hazard, exposure, and vulnerability at a river basin, it is obviously hard to identify the distribution and locations of continent-level flood risk based on national-level data. Therefore, we propose a methodological possibility for rapid global flood risk assessment with the results from its application to the two periods, i.e., Present (from 1980 to 2004) and Future (from 2075 to 2099). The method is particularly designed to effectively simplify complexities of a hazard area by calculating the differential inundation depth using GFID2M (global flood inundation depth 2-dimension model), despite low data availability. In this research, we addressed the question of which parts in the Eurasian region (8E to 180E, 0N to 60N) can be found as high-risk areas in terms of exposed population and economy in case of a 50-year return period flood. Economic losses were estimated according to the Shared Socioeconomic Pathways (SSP) scenario, and the flood scale was defined using the annual maximum daily river discharge under the extreme conditions of climate change simulated with MRI-AGCM3.2S based on the Representative Concentration Pathways (RCP8.5) emissions scenario. As a preliminary result, the total potential economic loss in the

  16. Rethinking the longitudinal stream temperature paradigm: region-wide comparison of thermal infrared imagery reveals unexpected complexity of river temperatures

    Science.gov (United States)

    We used an extensive dataset of remotely sensed summertime river temperature to compare longitudinal profiles (temperature versus distance) for 54 rivers in the Pacific Northwest. We evaluated (1) how often profiles fit theoretical expectations of asymptotic downstream warming, a...

  17. Influence of synoptic condition and holiday effects on VOCs and ozone production in the Yangtze River Delta region, China

    Science.gov (United States)

    Xu, Zhengning; Huang, Xin; Nie, Wei; Chi, Xuguang; Xu, Zheng; Zheng, Longfei; Sun, Peng; Ding, Aijun

    2017-11-01

    Both anthropogenic emission and synoptic conditions play important roles in ozone (O3) formation and accumulation. In order to understand the influence of synoptic condition and holiday effects on ozone production in the Yangtze River Delta region, China, concentrations of speciated volatile organic compounds (VOCs) and O3 as well as other relevant trace gases were simultaneously measured at the Station for Observing Regional Processes of the Earth System (SORPES) in Nanjing around the National Day holidays of China in 2014, which featured substantial change of emissions and dominated by typical anti-cyclones. Different groups of VOC species and their chemical reactivities were comprehensively analyzed. We observed clear diurnal variations of short alkenes during the measurement period, considerable amount of short alkenes were observed during night (more than 10 ppb) while almost no alkenes were measured during daytime, which might be attributed to different chemical processes. The obvious enhancement of the VOC tracers during the National Day holidays (Oct. 1st-Oct. 7th) indicated that the holiday effect strongly influenced the distribution of VOC profile and chemical reactivity in the atmosphere. At the same time, two meso-scale anticyclone processes were also observed during the measurement period. The synoptic condition contributed to the accumulation of VOCs and other precursors, which consequently impacted the ozone production in this region. The integrated influence of synoptic and holiday effects was also analyzed with an Observation Based Model (OBM) based on simplified MCM (Master Chemical Mechanism) chemical mechanism. The calculated relative increment reactivity (RIR) of different VOC groups revealed that during the holidays, this region was in VOC-limited regime and the variation of RIR shows a close linkage to the development and elimination of anti-cyclones, indicating an in-negligible contribution of synoptic effect toward ozone production in this

  18. Alaska Resource Data File, Nabesna quadrangle, Alaska

    Science.gov (United States)

    Hudson, Travis L.

    2003-01-01

    Descriptions of the mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska.

  19. Geology and Geochemistry of the Poco de Fora region-Curaca river valley-Bahia-Brazil

    International Nuclear Information System (INIS)

    Figueiredo, M.C.H. de.

    1976-01-01

    In the Poco de Fora region level rocks of light metamorphism, from Caraiba group, corresponding to: - a meta-sedimentar sequence from Lower Pre-cambrian (Archean) - maphic-ultramaphic bodies with Fe and Cu sulphides of volcanogenic origin, and - sienitic ortho-gneiss. Geological, petrographic, geochemistry and geochronological studies were done. The sienitic-intrusion, from the upper crust, occur during the Archean-beginning of the Proterozoic. All the region was re-mobilized, and the sienitic was metamorphosed during Transamazonic Orogeny (2.200 to 1.800 m.y.). (C.D.G.) [pt

  20. Earthquake Hazard and Risk in Alaska

    Science.gov (United States)

    Black Porto, N.; Nyst, M.

    2014-12-01

    Alaska is one of the most seismically active and tectonically diverse regions in the United States. To examine risk, we have updated the seismic hazard model in Alaska. The current RMS Alaska hazard model is based on the 2007 probabilistic seismic hazard maps for Alaska (Wesson et al., 2007; Boyd et al., 2007). The 2015 RMS model will update several key source parameters, including: extending the earthquake catalog, implementing a new set of crustal faults, updating the subduction zone geometry and reoccurrence rate. First, we extend the earthquake catalog to 2013; decluster the catalog, and compute new background rates. We then create a crustal fault model, based on the Alaska 2012 fault and fold database. This new model increased the number of crustal faults from ten in 2007, to 91 faults in the 2015 model. This includes the addition of: the western Denali, Cook Inlet folds near Anchorage, and thrust faults near Fairbanks. Previously the subduction zone was modeled at a uniform depth. In this update, we model the intraslab as a series of deep stepping events. We also use the best available data, such as Slab 1.0, to update the geometry of the subduction zone. The city of Anchorage represents 80% of the risk exposure in Alaska. In the 2007 model, the hazard in Alaska was dominated by the frequent rate of magnitude 7 to 8 events (Gutenberg-Richter distribution), and large magnitude 8+ events had a low reoccurrence rate (Characteristic) and therefore didn't contribute as highly to the overall risk. We will review these reoccurrence rates, and will present the results and impact to Anchorage. We will compare our hazard update to the 2007 USGS hazard map, and discuss the changes and drivers for these changes. Finally, we will examine the impact model changes have on Alaska earthquake risk. Consider risk metrics include average annual loss, an annualized expected loss level used by insurers to determine the costs of earthquake insurance (and premium levels), and the

  1. EarthScope Transportable Array Siting Outreach Activities in Alaska and Western Canada

    Science.gov (United States)

    Dorr, P. M.; Gardine, L.; Tape, C.; McQuillan, P.; Cubley, J. F.; Samolczyk, M. A.; Taber, J.; West, M. E.; Busby, R.

    2015-12-01

    The EarthScope Transportable Array is deploying about 260 stations in Alaska and western Canada. IRIS and EarthScope are partnering with the Alaska Earthquake Center, part of the University of Alaska's Geophysical Institute, and Yukon College to spread awareness of earthquakes in Alaska and western Canada and the benefits of the Transportable Array for people living in these regions. We provide an update of ongoing education and outreach activities in Alaska and Canada as well as continued efforts to publicize the Transportable Array in the Lower 48. Nearly all parts of Alaska and portions of western Canada are tectonically active. The tectonic and seismic variability of Alaska, in particular, requires focused attention at the regional level, and the remoteness and inaccessibility of most Alaskan and western Canadian villages and towns often makes frequent visits difficult. When a community is accessible, every opportunity to engage the residents is made. Booths at state fairs and large cultural gatherings, such as the annual convention of the Alaska Federation of Natives, are excellent venues to distribute earthquake information and to demonstrate a wide variety of educational products and web-based applications related to seismology and the Transportable Array that residents can use in their own communities. Meetings and interviews with Alaska Native Elders and tribal councils discussing past earthquakes has led to a better understanding of how Alaskans view and understand earthquakes. Region-specific publications have been developed to tie in a sense of place for residents of Alaska and the Yukon. The Alaska content for IRIS's Active Earth Monitor emphasizes the widespread tectonic and seismic features and offers not just Alaska residents, but anyone interested in Alaska, a glimpse into what is going on beneath their feet. The concerted efforts of the outreach team will have lasting effects on Alaskan and Canadian understanding of the seismic hazard and

  2. Invasive sweetclover (Melilotus alba) impacts native seeding recruitment along floodplains of interior Alaska

    Science.gov (United States)

    Blaine T. Spellman; Tricia L. Wurtz

    2011-01-01

    Sweetclover (Melilotus alba) is a nonnative legume that has formed dense and extensive patches along several rivers in Alaska. Our research objective was to determine if sweetclover impacts recruitment of native seedlings in floodplain habitats. To determine if sweetclover impacted recruitment, we conducted a removal experiment along two rivers in...

  3. Climate Change Impact Assessment for Surface Transportation in the Pacific Northwest and Alaska

    Science.gov (United States)

    2012-01-01

    The states in the Pacific Northwest and Alaska region share interconnected transportation networks for people, goods, and services that support the : regional economy, mobility, and human safety. Regional weather has and will continue to affect the p...

  4. The nitrogen cycle in highly urbanized tropical regions and the effect of river-aquifer interactions: The case of Jakarta and the Ciliwung River

    Science.gov (United States)

    Costa, Diogo; Burlando, Paolo; Priadi, Cindy; Shie-Yui, Liong

    2016-09-01

    Groundwater is extensively used in Jakarta to compensate for the limited public water supply network. Recent observations show a rise in nitrate (NO3-) levels in the shallow aquifer, thus pointing at a potential risk for public health. The detected levels are still below national and international regulatory limits for drinking water but a strategy is necessary to contain the growing problem. We combine 3 years of available data in the Ciliwung River, the major river flowing through Jakarta, with a distributed river-aquifer interaction model to characterise the impact of urbanisation on the N-cycle of both surface and groundwater systems. Results show that the N-cycle in the river-aquifer system is heterogeneous in space, seasonal dependent (i.e. flow regime) and strongly affected by urban pollution. Results suggest also that although the main sources of N related groundwater pollution are leaking septic tanks, the aquifer interaction with the Ciliwung River may locally have a strong effect on the concentrations. In the general context of pollution control in urban areas, this study demonstrates how advanced process-based models can be efficiently used in combination with field measurements to bring new insights into complex contamination problems. These are essential for more effective and integrated management of water quality in river-aquifer systems.

  5. Phytomass in southeast Alaska.

    Science.gov (United States)

    Bert R. Mead

    1998-01-01

    Phytomass tables are presented for the southeast Alaska archipelago. Average phytomass for each sampled species of tree, shrub, grass, forb, lichen, and moss in 10 forest and 4 nonforest vegetation types is shown.

  6. Geothermal Technologies Program: Alaska

    Energy Technology Data Exchange (ETDEWEB)

    2005-02-01

    This fact sheets provides a summary of geothermal potential, issues, and current development in Alaska. This fact sheet was developed as part of DOE's GeoPowering the West initiative, part of the Geothermal Technologies Program.

  7. Employee, State of Alaska

    Science.gov (United States)

    Business Resources Division of Corporations, Business & Professional Licensing Dept. of Commerce Benefits Resources State Employee Directory State Calendar State Training: LearnAlaska State Travel Manager) Web Mail (Outlook) Login Who to Call Health Insurance Insurance Benefits Health and Optional

  8. Development of a global river-coastal coupling model and its application to flood simulation in Asian mega-delta regions

    Science.gov (United States)

    Ikeuchi, Hiroaki; Hirabayashi, Yukiko; Yamazaki, Dai; Muis, Sanne; Ward, Philip; Verlaan, Martin; Winsemius, Hessel; Kanae, Shinjiro

    2017-04-01

    The world's mega-delta regions and estuaries are susceptible to various water-related disasters, such as river flooding and storm surge. Moreover, simultaneous occurrence of them would be more devastating than a situation where they occur in isolation. Therefore, it is important to provide information about compound risks of fluvial and coastal floods at a large scale, both their statistical dependency as well as their combined resulting flooding in delta regions. Here we report on a first attempt to address this issue globally by developing a method to couple a global river model (CaMa-Flood) and a global tide and surge reanalysis (GTSR) dataset. A state-of-the-art global river routing model, CaMa-Flood, was modified to represent varying sea levels due to tides and storm surges as downstream boundary condition, and the GTSR dataset was post-processed to serve as inputs to the CaMa-Flood river routing simulation and a long-term simulation was performed to incorporate the temporal dependency between coastal tide and surge on the one hand, and discharge on the other. The coupled model was validated against observations, showing better simulation results of water levels in deltaic regions than simulation without GTSR. For example in the Ganges Delta, correlation coefficients were increased by 0.06, and root mean square errors were reduced by 0.22 m. Global coupling simulations revealed that storm surges affected river water levels in coastal regions worldwide, especially in low-lying flat areas with increases in water level larger than 0.5 m. By employing enhanced storm surge simulation with tropical storm tracks, we also applied the model to examine impacts of past hurricane and cyclone storm events on river flood inundation.

  9. Estimation of reservoir inflow in data scarce region by using Sacramento rainfall runoff model - A case study for Sittaung River Basin, Myanmar

    Science.gov (United States)

    Myo Lin, Nay; Rutten, Martine

    2017-04-01

    The Sittaung River is one of four major rivers in Myanmar. This river basin is developing fast and facing problems with flood, sedimentation, river bank erosion and salt intrusion. At present, more than 20 numbers of reservoirs have already been constructed for multiple purposes such as irrigation, domestic water supply, hydro-power generation, and flood control. The rainfall runoff models are required for the operational management of this reservoir system. In this study, the river basin is divided into (64) sub-catchments and the Sacramento Soil Moisture Accounting (SAC-SMA) models are developed by using satellite rainfall and Geographic Information System (GIS) data. The SAC-SMA model has sixteen calibration parameters, and also uses a unit hydrograph for surface flow routing. The Sobek software package is used for SAC-SMA modelling and simulation of river system. The models are calibrated and tested by using observed discharge and water level data. The statistical results show that the model is applicable to use for data scarce region. Keywords: Sacramento, Sobek, rainfall runoff, reservoir

  10. Evaluation of Unmanned Aircraft System (UAS) to Monitor Forest Health Conditions in Alaska

    Science.gov (United States)

    Webley, P. W.; Hatfield, M. C.; Heutte, T. M.; Winton, L. M.

    2017-12-01

    US Forest Service Alaska Region Forest Health Protection (FHP) and University of Alaska Fairbanks (UAF), Alaska Center for Unmanned Aircraft Systems Integration (ACUASI) are evaluating the capability of Unmanned Aerial Systems (UAS, "drone" informally) to monitor forest health conditions in Alaska's Interior Region. On July 17-20 2017, FHP and ACUASI deployed two different UAS at permanent forest inventory plots managed by the UAF programs Bonanza Creek Long Term Ecological Research (LTER) and Cooperative Alaska Forest Inventory (CAFI). The purpose of the mission was to explore capabilities of UAS for evaluating aspen tree mortality at inaccessible locations and at a scale and precision not generally achievable with currently used ground- or air-based methods. Drawing from experience gained during the initial 2016 campaign, this year emphasized the efficient use of UAS to accomplish practical field research in a variety of realistic situations. The vehicles selected for this years' effort included the DJI Matrice quadcopter with the Zenmuse-X3 camera to quickly capture initial video of the site and tree conditions; followed by the ING Responder (single rotor electric helicopter based on the Gaui X7 airframe) outfitted with a Nikon D810 camera to collect high-resolution stills suitable for construction of orthomosaic models. A total of 12 flights were conducted over the campaign, with two full days dedicated to the Delta Junction Gerstle River Intermediate (GRI) sites and the remaining day at the Bonanza Creek site. In addition to demonstrating the ability of UAS to operate safely and effectively in various canopy conditions, the effort also validated the ability of teams to deliver UAS and scientific payloads into challenging terrain using all-terrain vehicles (ATV) and foot traffic. Analysis of data from the campaign is underway. Because the permanent plots have been recently evaluated it is known that nearly all aspen mortality is caused by an aggressive canker

  11. Impact of {sup 210}PB from Osamu Utsumi mine on sediment of rivers in Caldas Region, Minas Gerais

    Energy Technology Data Exchange (ETDEWEB)

    Dutra, Pedro Henrique; Menezes, Maria Angela B.C. de; Moreira, Rubens Martins; Carvalho Filho, Carlos Alberto de, E-mail: phd@cdtn.br, E-mail: menezes@cdtn.br, E-mail: rubens@cdtn.br, E-mail: cacf@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    The Osamu Utsumi Mine of the Industrias Nucleares do Brasil (INB) is located in Caldas region, Minas Gerais, Brazil. It is a uranium mining and is in process of shutdown, decommissioning stage. CDTN/CNEN (Nuclear Technology Development Center, sponsored by Brazilian Commission for Nuclear Energy) is participating in this decommission step. One contribution will be the characterization of the environmental liability, determining the impact on the environment caused by mining activities. Several radionuclides are being analysed in diversified matrixes, however, this paper is about determination of {sup 210}Pb in sediment of rivers. One reason to analyse {sup 210}Pb is due to its long half-life (22.3 years) that may point out the carrier of {sup 222}Rn, {sup 226}Ra, {sup 228}Ra, even U, in the region. Besides, it may be used to date sediment. The methodology applied to determine the {sup 210}Pb activity in sediment was gamma spectrometry that was established at CDTN during the development of this study. The results confirmed the impact of the uranium mining on the environment. (author)

  12. [Prediction and simulation of urban area expansion in Pearl River Delta Region under the RCPs climate scenarios].

    Science.gov (United States)

    Jiang, Oun-ou; Deng, Xiang-zheng; Ke, Xin-li; Zhao, Chun-hong; Zhang, Wei

    2014-12-01

    The sizes and number of cities in China are increasing rapidly and complicated changes of urban land use system have occurred as the social economy develops rapidly. This study took the urban agglomeration of Pearl River Delta Region as the study area to explore the driving mechanism of dynamic changes of urban area in the urbanization process under the joint influence of natural environment and social economic conditions. Then the CA (cellular automata) model was used to predict and simulate the urban area changes until 2030 under the designed scenarios of planning and RCPs (representative concentration pathways). The results indicated that urbanization was mainly driven by the non-agricultural population growth and social-economic development, and the transportation had played a fundamental role in the whole process, while the areas with high elevation or steep slope restricted the urbanization. Besides, the urban area would keep an expanding trend regardless of the scenarios, however, the expanding speed would slow down with different inflection points under different scenarios. The urban expansion speed increased in the sequence of the planning scenario, MESSAGE scenario and AIM scenario, and that under the MESSAGE climate scenario was more consistent with the current urban development trend. In addition, the urban expansion would mainly concentrate in regions with the relatively high urbanization level, e.g., Guangzhou, Dongguan, Foshan, Shenzhen, Zhanjiang and Chaoshan.

  13. Impact of 210PB from Osamu Utsumi mine on sediment of rivers in Caldas Region, Minas Gerais

    International Nuclear Information System (INIS)

    Dutra, Pedro Henrique; Menezes, Maria Angela B.C. de; Moreira, Rubens Martins; Carvalho Filho, Carlos Alberto de

    2013-01-01

    The Osamu Utsumi Mine of the Industrias Nucleares do Brasil (INB) is located in Caldas region, Minas Gerais, Brazil. It is a uranium mining and is in process of shutdown, decommissioning stage. CDTN/CNEN (Nuclear Technology Development Center, sponsored by Brazilian Commission for Nuclear Energy) is participating in this decommission step. One contribution will be the characterization of the environmental liability, determining the impact on the environment caused by mining activities. Several radionuclides are being analysed in diversified matrixes, however, this paper is about determination of 210 Pb in sediment of rivers. One reason to analyse 210 Pb is due to its long half-life (22.3 years) that may point out the carrier of 222 Rn, 226 Ra, 228 Ra, even U, in the region. Besides, it may be used to date sediment. The methodology applied to determine the 210 Pb activity in sediment was gamma spectrometry that was established at CDTN during the development of this study. The results confirmed the impact of the uranium mining on the environment. (author)

  14. Mining in the Alligator Rivers Region, northern Australia: Assessing potential and actual effects on ecosystem and human health

    International Nuclear Information System (INIS)

    Dam, R.A. van; Humphrey, C.L.; Martin, P.

    2002-01-01

    This paper presents an overview of issues related to surface water contamination arising from uranium mining activities in the Alligator Rivers Region (ARR) of northern Australia, and a program of research and monitoring that must assess the potential and actual effects on ecosystem and human health. The program of assessing effects on aquatic ecosystems involves a four-tiered approach including the derivation of local water quality guideline trigger values, direct toxicity assessment of mine waters prior to their release, creekside or in situ monitoring for early warning of adverse effects during mine water release, and longer-term monitoring of macroinvertebrate and fish communities. Bioaccumulation in aquatic biota is also assessed, and is an issue of importance not only to ecosystem health, but also to the health of local Aboriginal people. The aquatic animals they consume represent potential sources of radiological dose, and as a result, a major component of the program to assess potential effects on human health is the prediction of doses to Aboriginal people living downstream of mining activities. Acknowledging the assumptions and uncertainties, the calculation of concentration factors for local aquatic (and other) food sources allows the prediction of potential radiological exposure to people following hypothetical mine water releases. The approaches described form the basis of best-practice protocols that are relevant at both regional and national levels

  15. From fresh to marine waters: characterization and fate of dissolved organic matter in the Lena River delta region, Siberia

    Directory of Open Access Journals (Sweden)

    Rafael eGonçalves-Araujo

    2015-12-01

    Full Text Available Connectivity between the terrestrial and marine environment in the Artic is changing as a result of climate change, influencing both freshwater budgets and the supply of carbon to the sea. This study characterizes the optical properties of dissolved organic matter (DOM within the Lena Delta region and evaluates the behavior of DOM across the fresh water-marine gradient. Six fluorescent components (four humic-like; one marine humic-like; one protein-like were identified by Parallel Factor Analysis (PARAFAC with a clear dominance of allochthonous humic-like signals. Colored DOM (CDOM and dissolved organic carbon (DOC were highly correlated and had their distribution coupled with hydrographical conditions. Higher DOM concentration and degree of humification were associated with the low salinity waters of the Lena River. Values decreased towards the higher salinity Laptev Sea shelf waters. Results demonstrate different responses of DOM mixing in relation to the vertical structure of the water column, as reflecting the hydrographical dynamics in the region. Two mixing curves for DOM were apparent. In surface waters above the pycnocline there was a sharper decrease in DOM concentration in relation to salinity indicating removal. In the bottom water layer the DOM decrease within salinity was less. We propose there is a removal of DOM occurring primarily at the surface layer, which is likely driven by photodegradation and flocculation.

  16. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China

    Science.gov (United States)

    Zhang, Ling; Nan, Zhuotong; Xu, Yi; Li, Shuo

    2016-01-01

    Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995–2014) and near future (2015–2024), by combining two land use models (i.e., Markov chain model and Dyna-CLUE) with a hydrological model (i.e., SWAT). The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses. PMID:27348224

  17. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China.

    Science.gov (United States)

    Zhang, Ling; Nan, Zhuotong; Xu, Yi; Li, Shuo

    2016-01-01

    Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995-2014) and near future (2015-2024), by combining two land use models (i.e., Markov chain model and Dyna-CLUE) with a hydrological model (i.e., SWAT). The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses.

  18. Correlates of Alaska Native Fatal and Nonfatal Suicidal Behaviors 1990-2001

    Science.gov (United States)

    Wexler, Lisa; Hill, Ryan; Bertone-Johnson, Elizabeth; Fenaughty, Andrea

    2008-01-01

    Factors correlated with suicidal behavior in a predominately Alaska Native region of Alaska are described, and the correlates relating to fatal and nonfatal suicide behaviors in this indigenous population are distinguished. Suicide data from the region (1990-2001) were aggregated and compared to 2000 U.S. Census Data using chi-squared tests.…

  19. Evaluation of regional-scale water level simulations using various river routing schemes within a hydrometeorological modelling framework for the preparation of the SWOT mission

    Science.gov (United States)

    Häfliger, V.; Martin, E.; Boone, A. A.; Habets, F.; David, C. H.; Garambois, P. A.; Roux, H.; Ricci, S. M.; Thévenin, A.; Berthon, L.; Biancamaria, S.

    2014-12-01

    The ability of a regional hydrometeorological model to simulate water depth is assessed in order to prepare for the SWOT (Surface Water and Ocean Topography) mission that will observe free surface water elevations for rivers having a width larger than 50/100 m. The Garonne river (56 000 km2, in south-western France) has been selected owing to the availability of operational gauges, and the fact that different modeling platforms, the hydrometeorological model SAFRAN-ISBA-MODCOU and several fine scale hydraulic models, have been extensively evaluated over two reaches of the river. Several routing schemes, ranging from the simple Muskingum method to time-variable parameter kinematic and diffusive waves schemes with time varying parameters, are tested using predetermined hydraulic parameters. The results show that the variable flow velocity scheme is advantageous for discharge computations when compared to the original Muskingum routing method. Additionally, comparisons between water level computations and in situ observations led to root mean square errors of 50-60 cm for the improved Muskingum method and 40-50 cm for the kinematic-diffusive wave method, in the downstream Garonne river. The error is larger than the anticipated SWOT resolution, showing the potential of the mission to improve knowledge of the continental water cycle. Discharge computations are also shown to be comparable to those obtained with high-resolution hydraulic models over two reaches. However, due to the high variability of river parameters (e.g. slope and river width), a robust averaging method is needed to compare the hydraulic model outputs and the regional model. Sensitivity tests are finally performed in order to have a better understanding of the mechanisms which control the key hydrological processes. The results give valuable information about the linearity, Gaussianity and symetry of the model, in order to prepare the assimilation of river heights in the model.

  20. Future changes in peak river flows across northern Eurasia as inferred from an ensemble of regional climate projections under the IPCC RCP8.5 scenario

    Science.gov (United States)

    Shkolnik, Igor; Pavlova, Tatiana; Efimov, Sergey; Zhuravlev, Sergey

    2018-01-01

    Climate change simulation based on 30-member ensemble of Voeikov Main Geophysical Observatory RCM (resolution 25 km) for northern Eurasia is used to drive hydrological model CaMa-Flood. Using this modeling framework, we evaluate the uncertainties in the future projection of the peak river discharge and flood hazard by 2050-2059 relative to 1990-1999 under IPCC RCP8.5 scenario. Large ensemble size, along with reasonably high modeling resolution, allows one to efficiently sample natural climate variability and increase our ability to predict future changes in the hydrological extremes. It has been shown that the annual maximum river discharge can almost double by the mid-XXI century in the outlets of major Siberian rivers. In the western regions, there is a weak signal in the river discharge and flood hazard, hardly discernible above climate variability. Annual maximum flood area is projected to increase across Siberia mostly by 2-5% relative to the baseline period. A contribution of natural climate variability at different temporal scales to the uncertainty of ensemble prediction is discussed. The analysis shows that there expected considerable changes in the extreme river discharge probability at locations of the key hydropower facilities. This suggests that the extensive impact studies are required to develop recommendations for maintaining regional energy security.

  1. CONFLICT OF AQUATIC RESOURCES AND ITS UNDERLYING CAUSES: A CASE STUDY FROM DONAN RIVER AREA, SEGARA ANAKAN REGION, CILACAP, CENTRAL JAVA

    Directory of Open Access Journals (Sweden)

    Taufik Budhi Pramono

    2009-04-01

    Full Text Available This research aimed to know internally conflict on the use of aquatic  resources at around Donan River, Segara Anakan region Cilacap.  Using on fisheries resources was not free against potential conflict among the user or with its interest’s one related to that resources.  The lack on capability of identified conflict would be a limiting factor for the implementation on the fisheries resources management program.  The research was hold in the region of Segara Anakan, Donan River from August until October 2005.  The data collection techniques applied in this survey included questionnaire; observation; in-depth interview with leaders of fisherman organizations; and focus group discussion. Quantitative data was analyzed by descriptive statistics.  The research showed that fisherman’s community along Donan River line were not out of inside potentially conflict among inter micro-micro, intra micro-micro and intra micro-macro.  This potential conflict were appeared because of presence on the different perception belong to its authority access against Donan River and their open system on the fisheries resources management.Keywords : Conflict, Donan River, Aquatic Resources, Fisherman Community

  2. Distribution and mobility of mercury in soils of a gold mining region, Cuyuni river basin, Venezuela.

    Science.gov (United States)

    Santos-Francés, F; García-Sánchez, A; Alonso-Rojo, P; Contreras, F; Adams, M

    2011-04-01

    An extensive and remote gold mining region located in the East of Venezuela has been studied with the aim of assessing the distribution and mobility of mercury in soil and the level of Hg pollution at artisanal gold mining sites. To do so, soils and pond sediments were sampled at sites not subject to anthropological influence, as well as in areas affected by gold mining activities. Total Hg in regionally distributed soils ranged between 0.02 mg kg(-1) and 0.40 mg kg(-1), with a median value of 0.11 mg kg(-1), which is slightly higher than soil Hg worldwide, possibly indicating long-term atmospheric input or more recent local atmospheric input, in addition to minor lithogenic sources. A reference Hg concentration of 0.3