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Sample records for salt lake tunisia

  1. Studies on the Biodiversity of Halophilic Microorganisms Isolated from El-Djerid Salt Lake (Tunisia under Aerobic Conditions

    Directory of Open Access Journals (Sweden)

    Abdeljabbar Hedi

    2009-01-01

    Full Text Available Bacterial and archaeal aerobic communities were recovered from sediments from the shallow El-Djerid salt lake in Tunisia, and their salinity gradient distribution was established. Six samples for physicochemical and microbiological analyses were obtained from 6 saline sites in the lake for physico-chemical and microbiological analyses. All samples studied were considered hypersaline with NaCl concentration ranging from 150 to 260 g/L. A specific halophilic microbial community was recovered from each site, and characterization of isolated microorganisms was performed via both phenotypic and phylogenetic approaches. Only one extreme halophilic organism, domain Archaea, was isolated from site 4 only, whereas organisms in the domain Bacteria were recovered from the five remaining sampling sites that contained up to 250 g/L NaCl. Members of the domain Bacteria belonged to genera Salicola, Pontibacillus, Halomonas, Marinococcus, and Halobacillus, whereas the only member of domain Archaea isolated belonged to the genus Halorubrum. The results of this study are discussed in terms of the ecological significance of these microorganisms in the breakdown of organic matter in Lake El-Djerid and their potential for industry applications.

  2. Great Salt Lake, Utah

    Science.gov (United States)

    Stephens, Doyle W.; Gardner, Joe F.

    1999-01-01

    This document is intended as a source of general information and facts about Great Salt Lake, Utah. This U.S. Geological Survey information sheet answers frequently asked questions about Great Salt Lake. Topics include: History, salinity, brine shrimp, brine flies, migratory birds, and recreation. Great Salt Lake, the shrunken remnant of prehistoric Lake Bonneville, has no outlet. Dissolved salts accumulate in the lake by evaporation. Salinity south of the causeway has ranged from 6 percent to 27 percent over a period of 22 years (2 to 7 times saltier than the ocean). The high salinity supports a mineral industry that extracts about 2 million tons of salt from the lake each year. The aquatic ecosystem consists of more than 30 species of organisms. Harvest of its best-known species, the brine shrimp, annually supplies millions of pounds of food for the aquaculture industry worldwide. The lake is used extensively by millions of migratory and nesting birds and is a place of solitude for people. All this occurs in a lake that is located at the bottom of a 35,000-square-mile drainage basin that has a human population of more than 1.5 million.

  3. Salting our freshwater lakes

    Science.gov (United States)

    Bartlett, Sarah L.; Burke, Samantha M.; Doubek, Jonathan P.; Krivak-Tetley, Flora E.; Skaff, Nicholas K.; Summers, Jamie C.; Farrell, Kaitlin J.; McCullough, Ian M.; Morales-Williams, Ana M.; Roberts, Derek C.; Ouyang, Zutao; Scordo, Facundo; Hanson, Paul C.; Weathers, Kathleen C.

    2017-01-01

    The highest densities of lakes on Earth are in north temperate ecosystems, where increasing urbanization and associated chloride runoff can salinize freshwaters and threaten lake water quality and the many ecosystem services lakes provide. However, the extent to which lake salinity may be changing at broad spatial scales remains unknown, leading us to first identify spatial patterns and then investigate the drivers of these patterns. Significant decadal trends in lake salinization were identified using a dataset of long-term chloride concentrations from 371 North American lakes. Landscape and climate metrics calculated for each site demonstrated that impervious land cover was a strong predictor of chloride trends in Northeast and Midwest North American lakes. As little as 1% impervious land cover surrounding a lake increased the likelihood of long-term salinization. Considering that 27% of large lakes in the United States have >1% impervious land cover around their perimeters, the potential for steady and long-term salinization of these aquatic systems is high. This study predicts that many lakes will exceed the aquatic life threshold criterion for chronic chloride exposure (230 mg L−1), stipulated by the US Environmental Protection Agency (EPA), in the next 50 y if current trends continue. PMID:28396392

  4. Early Holocene Great Salt Lake

    Science.gov (United States)

    Oviatt, Charles G.; Madsen, David B.; Miller, David; Thompson, Robert S.; McGeehin, John P.

    2015-01-01

    Shorelines and surficial deposits (including buried forest-floor mats and organic-rich wetland sediments) show that Great Salt Lake did not rise higher than modern lake levels during the earliest Holocene (11.5–10.2 cal ka BP; 10–9 14C ka BP). During that period, finely laminated, organic-rich muds (sapropel) containing brine-shrimp cysts and pellets and interbedded sodium-sulfate salts were deposited on the lake floor. Sapropel deposition was probably caused by stratification of the water column — a freshwater cap possibly was formed by groundwater, which had been stored in upland aquifers during the immediately preceding late-Pleistocene deep-lake cycle (Lake Bonneville), and was actively discharging on the basin floor. A climate characterized by low precipitation and runoff, combined with local areas of groundwater discharge in piedmont settings, could explain the apparent conflict between evidence for a shallow lake (a dry climate) and previously published interpretations for a moist climate in the Great Salt Lake basin of the eastern Great Basin.

  5. Tunisia.

    Science.gov (United States)

    1987-02-01

    In 1986, Tunisia's population was 7,424,000, with an annual growth rate of 2.5%. The infant mortality rate was 90/1000 and life expectancy averages 58 years. The work force of 1,810,000 is distributed as follows: agriculture, 30.5%; manufacturing, 16.5%; services, 15.0%; construction and mining, 11.4%; and other, 26.6%. The gross domestic product was US$8.35 billion in 1985, with a per capita income (1986) of $1163. The Destourian Socialist Party has been the governing party in Tunisia since independence. Tunisia is a leader in the Arab world in the promotion of equal status for women under the law and the government supports an active family planning program. Tunisia's economy depends on oil, agriculture, phosphates, worker remittances, and tourism for economic growth. In response to an economic crisis in 1985-86, measures to restructure the economy were instituted, including basic commodity price increases, limits on wage increases, import liberalization, and price control modifications. Unemployment, aggravated by a rapidly growing work force, is a major problem in Tunisia. An estimated 50% of the potential work force is unemployed or underemployed.

  6. Monitoring Change in Great Salt Lake

    Science.gov (United States)

    Naftz, David; Angeroth, Cory; Freeman, Michael; Rowland, Ryan; Carling, Gregory

    2013-08-01

    Great Salt Lake is the largest hypersaline lake in the Western Hemisphere and the fourth largest terminal lake in the world (Figure 1). The open water and adjacent wetlands of the Great Salt Lake ecosystem support millions of migratory waterfowl and shorebirds from throughout the Western Hemisphere [Aldrich and Paul, 2002]. In addition, the area is of important economic value: Brine shrimp (Artemia franciscana) residing in Great Salt Lake support an aquaculture shrimp cyst industry with annual revenues as high as $60 million.

  7. Tunisia

    OpenAIRE

    World Bank

    2017-01-01

    As Tunisia emerges from the Arab Spring, its new constitution explicitly recognizes the rights of the child and the responsibility of both the State and parents to act in the child’s best interest to guarantee dignity, healthcare, protection, and education. In accordance with these guarantees, the Tunisian Ministry of Women, Family, and Childhood (MFFE) has utilized the Systems Approach for ...

  8. Some Lake Level Control Alternatives for the Great Salt Lake

    OpenAIRE

    Allen, Marvin E.; Christensen, Ronald K.; Riley, J. Paul

    1983-01-01

    Fluctuations of the level of the Great Salt Lake cause large changes in both surface area and shoreline. Developments adjacent to the lake have been damaged by both high and low lake levels; and unless measures are implemented to regulate lake level fluctuations or otherwise to protect these developments, damages will continue. Various possible managment alternatives for mitigating potential damages from lake leve...

  9. Monitoring change in Great Salt Lake

    Science.gov (United States)

    Naftz, David L.; Angeroth, Cory E.; Freeman, Michael L.; Rowland, Ryan C.; Carling, Gregory

    2013-01-01

    Despite the ecological and economic importance of Great Salt Lake, only limited water quality monitoring has occurred historically. To change this, new monitoring stations and networks—gauges of lake level height and rate of inflow, moored buoys, and multiple lake-bottom sensors—will provide important information that can be used to make informed decisions regarding future management of the Great Salt Lake ecosystem.

  10. Reactive halogen species above salt lakes and salt pans

    OpenAIRE

    Holla, Robert

    2013-01-01

    Salt lakes can be found on all continents and saline soils cover 2.5% of the land surface of the earth (FAO, 2012). This thesis investigates the presence of reactive halogen species (RHS) above salt lakes and saline soils to evaluate their relevance for tropospheric chemistry of the planetary boundary layer. Ground-based MAX-DOAS and LP-DOAS measurements were conducted at salt lakes and two other sites with high halogen content. Prior to this work, RHS were found at three salt ...

  11. Anaglyph, Salt Lake City, Utah

    Science.gov (United States)

    2002-01-01

    The 2002 Winter Olympics are hosted by Salt Lake City at several venues within the city, in nearby cities, and within the adjacent Wasatch Mountains. This anaglyph image provides a stereoscopic map view of north central Utah that includes all of these Olympic sites. In the south, next to Utah Lake, Provo hosts the ice hockey competition. In the north, northeast of the Great Salt Lake, Ogden hosts curling and the nearby Snowbasin ski area hosts the downhill events. In between, southeast of the Great Salt Lake, Salt Lake City hosts the Olympic Village and the various skating events. Further east, across the Wasatch Mountains, the Park City ski resort hosts the bobsled, ski jumping, and snowboarding events. The Winter Olympics are always hosted in mountainous terrain. This view shows the dramatic landscape that makes the Salt Lake City region a world-class center for winter sports.The stereoscopic effect of this anaglyph was created by first draping a Landsat satellite image over a Shuttle Radar Topography Mission digital elevation model and then generating two differing perspectives, one for each eye. When viewed through special glasses, the result is a vertically exaggerated view of Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and cover the right eye with a blue filter.Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and will substantially help in analyzing the large and growing Landsat image archive, managed by the U.S. Geological Survey (USGS).Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed

  12. BAIA VERDE - SLANIC PRAHOVA SALTED LAKES COMPLEX

    Directory of Open Access Journals (Sweden)

    Monica SAVA

    2009-12-01

    Full Text Available Baia Verde – Slanic Prahova Lakes Complex have been formed by water accumulation resulted out of infiltrated salted water from bell shaped surface salt mines dated XVII century (1685. Such lakes, as per their method of formation, can be also found in other places from the SubCarpathians area (Telega – Prahova, Ocnele Mari – Valcea, Transilvanian Depression (Ocna Sibiului, Turda, Sovata, Ocna Dejului, etc.. Water contact with diapires, in the places where have always existed such mining explorations and exploitation, has determined the formation of salted lakes having balneary and therapeutically qualities and sometimes the development of a heliothermic / mezothermic bed. At Slanic – Prahova besides the three lakes known as Baia Verde 1, 2 and 3, there is also the lake Baia Baciului situated at the border of “Salt Mountain” which represented the first objective for capitalization of the balnear and therapeutically potential of the area.

  13. Albian salt-tectonics in Central Tunisia: Evidences for an Atlantic-type passive margin

    Science.gov (United States)

    Jaillard, Etienne; Bouillin, Jean-Pierre; Ouali, Jamel; Dumont, Thierry; Latil, Jean-Louis; Chihaoui, Abir

    2017-11-01

    Tunisia is part of the south-Tethyan margin, which comprises Triassic evaporites and a thick series of Jurassic and Cretaceous, mainly marine deposits, related to the Tethyan rifting evolution. A survey of various Cretaceous outcrops of central Tunisia (Kasserine-El Kef area), combined with literature descriptions, shows that the style of Albian deformation changes from the proximal (South) to the distal part (North) of the margin. The southern part is dominated by tilted blocks and growth faults, which evolve to the north to turtle-back and roll-over structures. Farther North, deformation is dominated by the extrusion of diapirs and salt walls. Such a distribution of deformation strongly suggests that the whole sedimentary cover glided northward on the Triassic evaporites during Albian times, as described for the Atlantic passive margin or for the Gulf of Mexico. Subsequently, these halokinetic structures have been folded during Alpine compressional tectonics.

  14. Early Holocene Great Salt Lake, USA

    Science.gov (United States)

    Oviatt, Charles G.; Madsen, David B.; Miller, David M.; Thompson, Robert S.; McGeehin, John P.

    2015-07-01

    Shorelines and surficial deposits (including buried forest-floor mats and organic-rich wetland sediments) show that Great Salt Lake did not rise higher than modern lake levels during the earliest Holocene (11.5-10.2 cal ka BP; 10-9 14C ka BP). During that period, finely laminated, organic-rich muds (sapropel) containing brine-shrimp cysts and pellets and interbedded sodium-sulfate salts were deposited on the lake floor. Sapropel deposition was probably caused by stratification of the water column - a freshwater cap possibly was formed by groundwater, which had been stored in upland aquifers during the immediately preceding late-Pleistocene deep-lake cycle (Lake Bonneville), and was actively discharging on the basin floor. A climate characterized by low precipitation and runoff, combined with local areas of groundwater discharge in piedmont settings, could explain the apparent conflict between evidence for a shallow lake (a dry climate) and previously published interpretations for a moist climate in the Great Salt Lake basin of the eastern Great Basin.

  15. 75 FR 22892 - Environmental Impact Statement: Salt Lake County, UT

    Science.gov (United States)

    2010-04-30

    ... Federal Highway Administration Environmental Impact Statement: Salt Lake County, UT AGENCY: Federal... transportation improvement project in Salt Lake County, Utah. FOR FURTHER INFORMATION CONTACT: Edward Woolford, Environmental Program Manager, Federal Highway Administration, 2520 West 4700 South, Suite 9A, Salt Lake City...

  16. 75 FR 9476 - Environmental Impact Statement: Salt Lake County, UT

    Science.gov (United States)

    2010-03-02

    ... Federal Highway Administration Environmental Impact Statement: Salt Lake County, UT AGENCY: Federal... transportation improvement project in Salt Lake County, Utah. FOR FURTHER INFORMATION CONTACT: Bryan Dillon, Area Engineer, Federal Highway Administration, 2520 West 4700 South, Suite 9A, Salt Lake City, UT 84118...

  17. Microseisms from the Great Salt Lake

    Science.gov (United States)

    Goddard, K. J.; Koper, K. D.; Burlacu, V.

    2014-12-01

    Dept. of Geology and Geophysics, University of Utah, Salt Lake City, UT, 84112, USA We performed frequency-dependent polarization and power analysis on continuous ambient seismic energy recorded by broadband seismic stations that were part of the Utah Regional Seismic Network (UU) for the years of 2001-2013. The number of broadband seismometers increased from 10 to 28 in this time period. As expected, at all 28 stations the single and double frequency peaks caused by microseisms were observed in the range of 3-20 s. At four of the stations located around the Great Salt Lake (BGU, HVU, NOQ, and SPU) an additional noise peak was intermittently observed in the period range of 0.8-1.2 s. This noise peak was strongest at SPU, a station located on the tip of a peninsula jutting into the lake from the north, and weakest at NOQ, a station located a few kilometers south of the lake in the Oquirrh Mountains. The noise peaks occur in both daytime and nighttime, and have durations lasting from a couple of hours to multiple days. They occur more frequently in the spring, summer, and fall, and less commonly in the winter. The occurrences of noise peaks in the summer show a day night pattern and seem to reach a peak during the night. The time dependence of this 1-s seismic noise was compared to records of wind speed measured at 1-hr intervals from nearby meteorological stations run by the NWS, and to lake level gage height measurements made by the USGS. Correlations with wind speed and lake level were done for every month of the year in 2013. Results showed that the correlations with wind varied throughout the year from a high of 0.49 in November to a low of 0.20 in the month of January. The correlation with lake level also varied throughout the year and the strongest correlation was found in the month of December with a correlation of 0.43. While these correlation values are statistically significant, neither wind nor lake level can completely explain the seismic observations

  18. Virus-host interactions in salt lakes.

    Science.gov (United States)

    Porter, Kate; Russ, Brendan E; Dyall-Smith, Michael L

    2007-08-01

    Natural hypersaline waters are widely distributed around the globe, as both continental surface waters and sea floor lakes, the latter being maintained by the large density difference between the hypersaline and overlying marine water. Owing to the extreme salt concentrations, close to or at saturation (approximately 35%, w/v), such waters might be expected to be devoid of life but, in fact, maintain dense populations of microbes. The majority of these microorganisms are halophilic prokaryotes belonging to the Domain Archaea, 'haloarchaea'. Viruses infecting haloarchaea are a vital part of hypersaline ecosystems, in many circumstances outnumbering cells by 10-100-fold. However, few of these 'haloviruses' have been isolated and even fewer have been characterised in molecular detail. In this review, we explore the methods used by haloviruses to replicate within their hosts and consider the implications of haloviral-haloarchaeal interactions for salt lake ecology.

  19. Distribution of organic contamination of sediments from Ichkeul Lake and Bizerte Lagoon, Tunisia.

    Science.gov (United States)

    Ben Salem, Fida; Ben Said, Olfa; Mahmoudi, Ezzeddine; Duran, Robert; Monperrus, Mathilde

    2017-09-14

    Analyses of organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and butyl tins (BuSn) were conducted on sediments from Ichkeul Lake-Bizerte Lagoon watershed (Tunisia). A total of 59 compounds (16 PAHs, 12 PCBs, 22 OCPs and 9 BuSn) were measured in 40 surface sediment samples collected during two campaigns. High concentrations of total PAHs were identified in the lagoon ranging from 122 to 19600ng·g(-1). Several OCPs, including endrin, dieldrin, and lindane (Hexachlorocyclohexane or HCH or BHC) were found in high concentrations in Ichkeul Lake, ranging from 28 to 2012ngg(-1). PAHs and OCPs varied seasonally, in response to the complex hydrology of the watershed. The concentrations of total PCBs ranged between 0.04 and 10.653ngg(-1) and suggests low total PCBs sediment contamination, when compared to most international criteria. Total BuSn concentrations range between 67 and 526ng·g(-1), which are relatively low when compared to most international criteria and ecological risk assessments. This is the first study of organic contamination in Ichkeul Lake (RAMSAR and UNESCO World Heritage site). Copyright © 2017. Published by Elsevier Ltd.

  20. How Do Changes to the Railroad Causeway in Utah's Great Salt Lake Affect Water and Salt Flow?: e0144111

    National Research Council Canada - National Science Library

    James S White; Sarah E Null; David G Tarboton

    2015-01-01

      Managing terminal lake elevation and salinity are emerging problems worldwide. We contribute to terminal lake management research by quantitatively assessing water and salt flow for Utah's Great Salt Lake...

  1. Stereo Pair, Salt Lake City, Utah

    Science.gov (United States)

    2002-01-01

    The 2002 Winter Olympics are hosted by Salt Lake City at several venues within the city, in nearby cities, and within the adjacent Wasatch Mountains. This image pair provides a stereoscopic map view of north central Utah that includes all of these Olympic sites. In the south, next to Utah Lake, Provo hosts the ice hockey competition. In the north, northeast of the Great Salt Lake, Ogden hosts curling and the nearby Snowbasin ski area hosts the downhill events. In between, southeast of the Great Salt Lake, Salt Lake City hosts the Olympic Village and the various skating events. Further east, across the Wasatch Mountains, the Park City ski resort hosts the bobsled, ski jumping, and snowboarding events. The Winter Olympics are always hosted in mountainous terrain. This view shows the dramatic landscape that makes the Salt Lake City region a world-class center for winter sports.This stereoscopic image was generated by draping a Landsat satellite image over a Shuttle Radar Topography Mission digital elevation model. Two differing perspectives were then calculated, one for each eye. They can be seen in 3-D by viewing the left image with the right eye and the right image with the left eye (cross-eyed viewing or by downloading and printing the image pair and viewing them with a stereoscope. When stereoscopically merged, the result is a vertically exaggerated view of Earth's surface in its full three dimensions.Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and will substantially help in analyzing the large and growing Landsat image archive, managed by the U.S. Geological Survey (USGS).Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR

  2. Salt Lake Community College Strategic Vision, September 2001-June 2006.

    Science.gov (United States)

    Salt Lake Community Coll., UT.

    This document reviews July 2001 findings from a team of Salt Lake Community College administrators, faculty, and staff who were appointed by the college President to prepare a strategic plan that defines the strategic vision of Salt Lake Community College. The team utilized a planning process that began with an evaluation of the external and…

  3. SALT LAKES OF THE AFRICAN RIFT SYSTEM: A VALUABLE ...

    African Journals Online (AJOL)

    dell

    ABSTRACT. The Tanzanian rift system salt lakes present significant cultural, ecological, recreational and economical values. Beyond the wealth of minerals, resources of these rift salt lakes include unique wildlife, for instance Lesser Flamingo (Phoenicopterus minor) and Cichlids (Alcolapia spp), which adapted chemically ...

  4. 78 FR 27872 - Proposed Amendment of Class E Airspace; Salt Lake City, UT

    Science.gov (United States)

    2013-05-13

    ... Federal Aviation Administration 14 CFR Part 71 Proposed Amendment of Class E Airspace; Salt Lake City, UT...: This action proposes to modify Class E airspace at Salt Lake City International Airport, Salt Lake City... operations at Salt Lake City International Airport. This action also would adjust the geographic coordinates...

  5. 77 FR 49712 - Amendment to Class B Airspace; Salt Lake City, UT

    Science.gov (United States)

    2012-08-17

    ... Federal Aviation Administration 14 CFR Part 71 RIN 2120-AA66 Amendment to Class B Airspace; Salt Lake City... modifies the Salt Lake City, UT, Class B airspace to contain aircraft conducting Instrument Flight Rules (IFR) instrument approach procedures to Salt Lake City International Airport (SLC), Salt Lake City, UT...

  6. Production of magnesium from Great Salt Lake, Utah USA

    OpenAIRE

    Tripp, Thomas G.

    2009-01-01

    Magnesium metal has been commercially produced from the waters of Great Salt Lake since 1972. Worldwide use of magnesium has markedly increased over the last twenty years due to its unique properties of low density and high strength. Great Salt Lake is a valuable resource for the recovery of magnesium minerals due to its chemical composition, natural geography/climate and proximity to transportation and markets. US Magnesium LLC and its predecessors have overcome various technical challenges ...

  7. Great Salt Lake basins study unit

    Science.gov (United States)

    Waddell, Kidd M.; Baskin, Robert L.

    1994-01-01

    In 1991, the U.S. Geological Survey (USGS) began implementing a full-scale National Water-Quality Assessment (NAWQA) Program.The long-term goals of the NAWQA Program are to describe the status and trends in the quality of a large, representative part of the Nation’s surface- and ground-water resources and to provide a sound, scientific understanding of the primary natural and human factors that affect the quality of these resources. In meeting these goals, the program will produce a wealth of water-quality information that will be useful to policy makers and managers at Federal, State, and local levels.A major design feature of the NAWQA Program will enable water-quality information at different areal scales to be integrated. A major component of the program is study-unit investigations, which ae the principal building blocks of the program upon which national-level assessment activities will be based. The 60 study-unit investigations that make up the program are hydrologic systems that include principal river basins and aquifer systems throughout the Nation. These study units cover areas from less than 1.000 to greater than 60,000 mi2 and incorporate from about 60 to 70 percent of the Nation’s water use and population served by public water supply. In 1993, assessment activities began in the Great Salt Lake Basins NAWQA study unit.

  8. Triassic salt sheets of Mezzouna, Central Tunisia: New comments on Late Cretaceous halokinesis and geodynamic evolution of the northern African margin

    Science.gov (United States)

    Dhahri, Ferid; Boukadi, Noureddine

    2017-05-01

    Two discrete Triassic salt sheets have been discovered within the Coniacian-Santonian series near the salt wall of Mezzouna, central Tunisia. The structure and the lithology of these sheets suggest two halokinetic episodes giving respectively 1) Triassic evaporitic rocks flows over a sloped basin floor resulting in probable salt glacier, and 2) redeposition of erosional debris from the nearby salt wall of Mezzouna, transported and then deposited next to the wall. This finding is used to precise the halokinetic events and the geodynamic evolution of the northern African margin near the Pelagian block between southeastern Tunisia and Tripolitania during Late Cretaceous. A discussion of the halokinesis-related structures is also attempted with emphasize of their genetic mechanisms and temporal development as inferred from geological mapping and new field data.

  9. The effects of restricted circulation on the salt balance of Great Salt Lake, Utah

    Science.gov (United States)

    Waddell, K.M.; Bolke, E.L.

    1973-01-01

    During the 1970-1972 water years a net load of dissolved solids of 0.26 billion tons moved from the south to north part of Great Salt Lake, Utah, through the causeway of the Southern Pacific Transportation Co. The load loss from the south part during the 1972 water year was only 0.01 billion tons, thus indicating that the salt balance between the two parts of the lake was near equilibrium for inflow conditions such as those of 1972.

  10. Great Salt Lake Past and Present: Elevation and Salinity Changes to Utah's Great Salt Lake from Railroad Causeway Alterations

    OpenAIRE

    White, James S.

    2015-01-01

    In 1959, Union Pacific Railroad constructed a rock-filled causeway bisecting Utah’s Great Salt Lake, separating the lake into a north and south arm. Flow between the two arms was limited to two 4.6 meter wide culverts installed during original construction, an 88 meter breach opening installed in 1984, and the semi porous boulder and gravel causeway material. The south arm receives nearly all streamflows entering Great Salt Lake and a salinity gradient between the two arms developed over time...

  11. [Microbial diversity of salt lakes in Badain Jaran desert].

    Science.gov (United States)

    Li, Lu; Hao, Chunbo; Wang, Lihua; Pei, Lixin

    2015-04-04

    We characterized procaryotic biodiversity, community structure and the relationship between the community structure and environmental factors of salt lakes in Badain Jaran desert, Inner Mongolia, China. We constructed 16S rRNA gene clone libraries by molecular biology techniques to analyze the procaryotic phylogenetic relationships, and used R language to compare the community structure of haloalkalophiles in the salt lakes. Water in this region has a high salinity ranging from 165 to 397 g/L. The water is strongly alkaline with pH value above 10. The microbial diversity and community structure of the salt lakes are obviously different. The diversity of bacteria is more abundant than that of archaea. The main categories of bacteria in the samples are Gammaproteobacteria, Bacteroidetes, Alphaproteobacteria, Firmicute and Verrucomicrobia, whereas all archaea only belong to Halobacteriaceae of Euryarchaeota. Salinity is the most important environmental factor influencing the bacterial community structure, whereas the archaea community structure was influenced comprehensively by multiple environmental factors.

  12. Draft Mercury Aquatic Wildlife Benchmarks for Great Salt Lake ...

    Science.gov (United States)

    This document describes the EPA Region 8's rationale for selecting aquatic wildlife dietary and tissue mercury benchmarks for use in interpreting available data collected from the Great Salt Lake and surrounding wetlands. EPA Region 8 has conducted a literature review to update and refine the aquatic wildlife dietary and tissue benchmarks for mercury that may be used for data assessment until water quality criteria can be derived. The document describes how aquatic wildlife dietary and tissue benchmarks for mercury have been compiled for existing literature sources and the approach for how they will be used to evaluate whether the Great Salt Lake and surrounding wetlands meet its designated use for aquatic wildlife.

  13. Clean Cities Award Winning Coalition: Salt Lake City

    Energy Technology Data Exchange (ETDEWEB)

    ICF Kaiser

    1999-05-20

    Since its designation as a national Clean City in 1994, Salt Lake Clean Cities has put more than 2,600 alternative fuel vehicles (AFVs) on community streets. The 82 business, nonprofit, and government agencies that comprise the coalition are all dedicated to cleaning the air by reducing vehicle exhaust. Salt Lake Clean Cities has the third largest compressed natural gas and propane-refueling infrastructure in the country, with 98 locations available. They sponsor an annual ''Spring Soiree'' to increase public awareness about the program and educate the public about the benefits of alternative fuel and AFVs.

  14. Investigations on boron isotopic geochemistry of salt lakes in Qaidam basin, Qinghai

    Digital Repository Service at National Institute of Oceanography (India)

    Xiao, Y.K.; Shirodkar, P.V.; Liu, W.G.; Wang, Y.H.; Jin, L.

    The isotopic compositions of boron in salt lakes located in Qaidam Basin, Qinghai, have been determined using the procedure of thermal ionization mass spectrometry of cesium borate with graphite loading. The salt lakes were controlled by evaporation...

  15. 75 FR 73983 - Proposed Modification of the Salt Lake City, UT, Class B Airspace Area; Public Meetings

    Science.gov (United States)

    2010-11-30

    ... Federal Aviation Administration 14 CFR Part 71 Proposed Modification of the Salt Lake City, UT, Class B... Terminal, 397 North 2370 West, Salt Lake City, UT 84116. (3) The meeting on Thursday, February 3, 2011... Lake City TRACON, Salt Lake City ATCT/TRACON, 1201 North 4000 West, Salt Lake City, UT 84116. (801) 325...

  16. 78 FR 76781 - Proposed Modification of Class B Airspace; Salt Lake City, UT

    Science.gov (United States)

    2013-12-19

    ...; Salt Lake City, UT AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... Salt Lake City Class B surface area and the Hill Air Force Base (AFB) Class D airspace area. This... north and south through the Salt Lake Valley over Interstate 15. DATES: Comments must be received on or...

  17. 78 FR 2434 - Notice of Inventory Completion: Natural History Museum of Utah, Salt Lake City, UT

    Science.gov (United States)

    2013-01-11

    ... National Park Service Notice of Inventory Completion: Natural History Museum of Utah, Salt Lake City, UT..., Salt Lake City, UT 84108, telephone (801) 581-3876. SUPPLEMENTARY INFORMATION: Notice is here given in..., Salt Lake City, UT 84108, telephone (801) 581-3876, before February 11, 2013. Repatriation of the human...

  18. 78 FR 2430 - Notice of Inventory Completion: Natural History Museum of Utah, Salt Lake City, UT

    Science.gov (United States)

    2013-01-11

    ... National Park Service Notice of Inventory Completion: Natural History Museum of Utah, Salt Lake City, UT... February 11, 2013. ADDRESSES: Duncan Metcalfe, Natural History Museum of Utah, 301 Wakara Way, Salt Lake... funerary objects should contact Duncan Metcalfe, Natural History Museum of Utah, 301 Wakara Way, Salt Lake...

  19. 78 FR 45848 - Amendment of Class E Airspace; Salt Lake City, UT

    Science.gov (United States)

    2013-07-30

    ... Federal Aviation Administration 14 CFR Part 71 Amendment of Class E Airspace; Salt Lake City, UT AGENCY... airspace at Salt Lake City, UT, to accommodate aircraft using Area Navigation (RNAV) Global Positioning... procedures at Salt Lake City International Airport. This improves the safety and management of Instrument...

  20. 76 FR 28074 - Notice of Inventory Completion: Utah Museum of Natural History, Salt Lake City, UT

    Science.gov (United States)

    2011-05-13

    ... National Park Service Notice of Inventory Completion: Utah Museum of Natural History, Salt Lake City, UT... inventory of human remains in the possession and control of the Utah Museum of Natural History, Salt Lake... Natural History, 1390 E. Presidents Circle, Salt Lake City, UT 84112, telephone (801) 581-3876, before...

  1. 76 FR 52905 - Proposed Amendment to Class B Airspace; Salt Lake City, UT

    Science.gov (United States)

    2011-08-24

    ... (NPRM). SUMMARY: This action proposes to modify Salt Lake City, UT, Class B airspace to contain aircraft conducting Instrument Flight Rules (IFR) instrument approach procedures to Salt Lake City International Airport (SCL), Salt Lake City, UT. The FAA is taking this action to improve the flow of air traffic...

  2. Salt Lake City, Utah: Solar in Action (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2011-10-01

    This brochure provides an overview of the challenges and successes of Salt Lake City, UT, a 2007 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given.

  3. Salt Lake hospital survives close brush with twister, power outage.

    Science.gov (United States)

    Magyar, C J

    1999-01-01

    LDS Hospital in Salt Lake City found that dealing with wounded and casualties from a natural disaster is just one problem; dealing with the natural disaster itself can be a whole other problem. A great success story in the midst of this summer's terrible tornado which hit Utah's capitol.

  4. Conceptual Model for Selenium Cycling in the Great Salt Lake

    Science.gov (United States)

    Johnson, W. P.; Conover, M. R.; Wurtsbaugh, W. A.; Adams, J.

    2006-12-01

    The conceptual model for Selenium cycling in the Great Salt Lake was developed to guide investigations in support of determining an open water selenium standard for the Great Salt Lake. The motivation to determine this particular selenium standard derives from public concern for a plan to allow disposal of reverse osmosis (RO) concentrate in the GSL, which would contain elevated concentrations of major and trace elements, including selenium. The development of an open water standard for selenium requires a working knowledge of the biological significance of existing selenium concentrations in the Great Salt Lake, as well as a working understanding of the likely changes of these concentrations over time given existing and proposed loads to the system. This working knowledge" is being represented in a conceptual model that accounts for selenium in various stocks" in the system (e.g. water, sediment, biota) and the flow" of selenium between stocks (e.g., precipitation and settling, volatilization, bioconcentration). It illustrates the critical pathway of selenium in the Great Salt Lake from water, to microorganisms, to brine shrimp and brine flies, to birds, and to their eggs. It also addresses the complexity of the GSL system: a) Spatially diverse, being comprised by four distinct bays and two layers, with major differences in salinity among their waters. b) Temporally dynamic, due to seasonal and inter-annual variations in runoff. The conceptual model is presently descriptive, but will serve as the basis for a semi-quantitative model that will be fed by data accumulated during subsequent investigations.

  5. Volatile Selenium Flux in the Great Salt Lake

    Science.gov (United States)

    Diaz, X.; Johnson, W. P.

    2006-12-01

    Volatilization of selenium has been proven to be the major source of selenium vapor from oceans and estuaries and it may be the major mechanism of permanent selenium removal from the Great Salt Lake (other than brine shrimp harvest). However, the volatilization flux of selenium from the Great Salt Lake has not been previously measured due to challenges of analysis in this hyper-saline environment. This work presents results from recent field studies examining the spatial distribution of volatile selenium (geographical and with depth) in the South Arm (main body) of the Great Salt Lake. The analyses involved collection of volatile selenium in a cryo-focusing trap system via sparging with helium. The cryo-trapped volatile selenium was digested with nitric acid and analyzed by ICP-MS. The results show concentrations of volatile selenium that are much greater than values reported for marine estuaries and oceans. Volatile selenium flux to the atmosphere was determined using mass transport equations corrected to simulate the highly saline environment of the South Arm of the Great Salt Lake.

  6. RadNet Air Data From Salt Lake City, UT

    Science.gov (United States)

    This page presents radiation air monitoring and air filter analysis data for Salt Lake City, UT from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.

  7. Physico-chemical and Microbiological Monitoring of Solotvino Salt Lakes

    Directory of Open Access Journals (Sweden)

    Chonka Y.

    2013-09-01

    Full Text Available Healing properties of salt lakes are due to physico-chemical and bacterial composition. So important is the study of physical and chemical properties of the water for the development of medical technologies and treatments of monitoring observations of the properties in terms of environmental issues.

  8. Disaster Preparedness: Lessons from the 2002 Salt Lake City Olympics.

    Science.gov (United States)

    Heaps, Richard A.

    Between February 7 and February 24, 2002, Utah and Salt Lake City hosted the Winter Olympics. Due to the bombing at the 1996 Summer Olympics in Atlanta and the emotional fallout that resulted, it was recommended that the Utah Psychological Association and Utah Red Cross plan for such an occurrence and organize a coordinated Disaster Mental Health…

  9. Water and salt balance of Great Salt Lake, Utah, and simulation of water and salt movement through the causeway

    Science.gov (United States)

    Wold, Steven R.; Thomas, Blakemore E.; Waddell, Kidd M.

    1997-01-01

    The water and salt balance of Great Salt Lake primarily depends on the amount of inflow from tributary streams and the conveyance properties of a causeway constructed during 1957-59 that divides the lake into the south and north parts. The conveyance properties of the causeway originally included two culverts, each 15 feet wide, and the permeable rock-fill material.During 1980-86, the salt balance changed as a result of record high inflow that averaged 4,627,000 acre-feet annually and modifications made to the conveyance properties of the causeway that included opening a 300-foot-wide breach. In this study, a model developed in 1973 by Waddell and Bolke to simulate the water and salt balance of the lake was revised to accommodate the high water-surface altitude and modifications made to the causeway. This study, done by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of State Lands and Forestry, updates the model with monitoring data collected during 1980-86. This report describes the calibration of the model and presents the results of simulations for three hypothetical 10-year periods.During January 1, 1980, to July 31, 1984, a net load of 0.5 billion tons of dissolved salt flowed from the south to the north part of the lake primarily as a result of record inflows. From August 1, 1984, when the breach was opened, to December 31,1986, a net load of 0.3 billion tons of dissolved salt flowed from the north to the south part of the lake primarily as a result of the breach.For simulated inflow rates during a hypothetical 10-year period resulting in the water-surface altitude decreasing from about 4,200 to 4,192 feet, there was a net movement of about 1.0 billion tons of dissolved salt from the south to the north part, and about 1.7 billion tons of salt precipitated in the north part. For simulated inflow rates during a hypothetical 10-year period resulting in a rise in water-surface altitude from about 4,200 to 4

  10. The ways of transformation of salt production from the saline lakes of Apsheron peninsula

    OpenAIRE

    В. А. Мамедов; Х. Х. Халилова

    2016-01-01

    The issues of salt production at salt lakes of Apsheron Peninsula in Azerbaijan are reviewed here. The paper objective is to examine the brine formation process and analyze the ways of transformation of salt extraction from the lakes of Apsheron Peninsula under ever increasing industrial development and urbanization. The research on ecological state of salt lakes at the peninsula have shown that the decades-long development of oil and gas and other industries had a dramatical impact on the na...

  11. Method for estimating road salt contamination of Norwegian lakes

    Science.gov (United States)

    Kitterød, Nils-Otto; Wike Kronvall, Kjersti; Turtumøygaard, Stein; Haaland, Ståle

    2013-04-01

    Consumption of road salt in Norway, used to improve winter road conditions, has been tripled during the last two decades, and there is a need to quantify limits for optimal use of road salt to avoid further environmental harm. The purpose of this study was to implement methodology to estimate chloride concentration in any given water body in Norway. This goal is feasible to achieve if the complexity of solute transport in the landscape is simplified. The idea was to keep computations as simple as possible to be able to increase spatial resolution of input functions. The first simplification we made was to treat all roads exposed to regular salt application as steady state sources of sodium chloride. This is valid if new road salt is applied before previous contamination is removed through precipitation. The main reasons for this assumption are the significant retention capacity of vegetation; organic matter; and soil. The second simplification we made was that the groundwater table is close to the surface. This assumption is valid for major part of Norway, which means that topography is sufficient to delineate catchment area at any location in the landscape. Given these two assumptions, we applied spatial functions of mass load (mass NaCl pr. time unit) and conditional estimates of normal water balance (volume of water pr. time unit) to calculate steady state chloride concentration along the lake perimeter. Spatial resolution of mass load and estimated concentration along the lake perimeter was 25 m x 25 m while water balance had 1 km x 1 km resolution. The method was validated for a limited number of Norwegian lakes and estimation results have been compared to observations. Initial results indicate significant overlap between measurements and estimations, but only for lakes where the road salt is the major contribution for chloride contamination. For lakes in catchments with high subsurface transmissivity, the groundwater table is not necessarily following the

  12. Water and salt balance of Great Salt Lake, Utah, and simulation of water and salt movement through the causeway, 1987-98

    Science.gov (United States)

    Loving, Brian L.; Miller, Craig W.; Waddell, Kidd M.

    2000-01-01

    The Southern Pacific Transportation Company completed a rock-fill causeway across Great Salt Lake in 1959. The effect of the causeway was to change the water and salt balance of Great Salt Lake by creating two separate but interconnected parts of the lake, with more than 95 percent of freshwater surface inflow entering the lake south of the causeway.The water and salt balance of Great Salt Lake primarily depends on the amount of inflow from tributary streams and the conveyance properties of the causeway that divides the lake into south and north parts. The conveyance properties of the causeway consist of two 15-foot-wide culverts, a 290-foot-wide breach, and permeable rock-fill material.

  13. The Younger Dryas phase of Great Salt Lake, Utah, USA

    Science.gov (United States)

    Oviatt, Charles G.; Miller, D.M.; McGeehin, J.P.; Zachary, C.; Mahan, S.

    2005-01-01

    Field investigations at the Public Shooting Grounds (a wildlife-management area on the northeastern shore of Great Salt Lake) and radiocarbon dating show that the Great Salt Lake rose to the Gilbert shoreline sometime between 12.9 and 11.2 cal ka. We interpret a ripple-laminated sand unit exposed at the Public Shooting Grounds, and dated to this time interval, as the nearshore sediments of Great Salt Lake deposited during the formation of the Gilbert shoreline. The ripple-laminated sand is overlain by channel-fill deposits that overlap in age (11.9-11.2 cal ka) with the sand, and by wetland deposits (11.1 to 10.5 cal ka). Consistent accelerator mass spectrometry radiocarbon ages were obtained from samples of plant fragments, including those of emergent aquatic plants, but mollusk shells from spring and marsh deposits yielded anomalously old ages, probably because of a variable radiocarbon reservoir effect. The Bonneville basin was effectively wet during at least part of the Younger Dryas global-cooling interval, however, conflicting results from some Great Basin locations and proxy records indicate that the regional effects of Younger Dryas cooling are still not well understood. ?? 2005 Elsevier B.V. All rights reserved.

  14. Microbial Biogeography of Six Salt Lakes in Inner Mongolia, China, and a Salt Lake in Argentina ▿ †

    Science.gov (United States)

    Pagaling, Eulyn; Wang, Huanzhi; Venables, Madeleine; Wallace, Andrew; Grant, William D.; Cowan, Don A.; Jones, Brian E.; Ma, Yanhe; Ventosa, Antonio; Heaphy, Shaun

    2009-01-01

    We used cultivation-independent methods to investigate the prokaryotic biogeography of the water column in six salt lakes in Inner Mongolia, China, and a salt lake in Argentina. These lakes had different salt compositions and pH values and were at variable geographic distances, on both local and intercontinental scales, which allowed us to explore the microbial community composition within the context of both contemporary environmental conditions and geographic distance. Fourteen 16S rRNA gene clone libraries were constructed, and over 200 16S rRNA gene sequences were obtained. These sequences were used to construct biotic similarity matrices, which were used in combination with environmental similarity matrices and a distance matrix in the Mantel test to discover which factors significantly influenced biotic similarity. We showed that archaeal biogeography was influenced by contemporary environmental factors alone (Na+, CO32−, and HCO3− ion concentrations; pH; and temperature). Bacterial biogeography was influenced both by contemporary environmental factors (Na+, Mg2+, and HCO3− ion concentrations and pH) and by geographic distance. PMID:19648369

  15. Culture conditions and salt effects on essential oil composition of sweet marjoram (Origanum majorana) from Tunisia.

    Science.gov (United States)

    Baâtour, Olfa; Tarchoune, Imen; Mahmoudi, Hela; Nassri, Nawel; Abidi, Wissal; Kaddour, Rym; Hamdaoui, Ghaith; Nasri-Ayachi, Mouhiba Ben; Lachaâl, Mohtar; Marzouk, Brahim

    2012-06-01

    O. majorana shoots were investigated for their essential oil (EO) composition. Two experiments were carried out; the first on hydroponic medium in a culture chamber and the second on inert sand in a greenhouse for 20 days. Plants were cultivated for 17 days in hydroponic medium supplemented with NaCl 100 mmol L⁻¹. The results showed that the O. majorana hydroponic medium offered higher essential oil yield than that from the greenhouse. The latter increased significantly in yield (by 50 %) under saline constraint while it did not change in the culture chamber. Under greenhouse conditions and in the absence of salt treatment, the major constituents were terpinen-4-ol and trans-sabinene hydrate. However, in the culture chamber, the major volatile components were cis-sabinene hydrate and terpinen-4-ol. In the presence of NaCl, new compounds appeared, such as eicosane, spathulenol, eugenol, and phenol. In addition, in the greenhouse, with or without salt, a very important change of trans-sabinene hydrate concentration in EO occurred, whereas in the culture chamber change appeared in cis-sabinene hydrate content.

  16. How Do Changes to the Railroad Causeway in Utah's Great Salt Lake Affect Water and Salt Flow?

    Directory of Open Access Journals (Sweden)

    James S White

    Full Text Available Managing terminal lake elevation and salinity are emerging problems worldwide. We contribute to terminal lake management research by quantitatively assessing water and salt flow for Utah's Great Salt Lake. In 1959, Union Pacific Railroad constructed a rock-filled causeway across the Great Salt Lake, separating the lake into a north and south arm. Flow between the two arms was limited to two 4.6 meter wide rectangular culverts installed during construction, an 88 meter opening (referred to locally as a breach installed in 1984, and the semi porous material of the causeway. A salinity gradient developed between the two arms of the lake over time because the south arm receives approximately 95% of the incoming streamflow entering Great Salt Lake. The north arm is often at, or near, salinity saturation, averaging 317 g/L since 1966, while the south is considerably less saline, averaging 142 g/L since 1966. Ecological and industrial uses of the lake are dependent on long-term salinity remaining within physiological and economic thresholds, although optimal salinity varies for the ecosystem and between diverse stakeholders. In 2013, Union Pacific Railroad closed causeway culverts amid structural safety concerns and proposed to replace them with a bridge, offering four different bridge designs. As of summer 2015, no bridge design has been decided upon. We investigated the effect that each of the proposed bridge designs would have on north and south arm Great Salt Lake elevation and salinity by updating and applying US Geological Survey's Great Salt Lake Fortran Model. Overall, we found that salinity is sensitive to bridge size and depth, with larger designs increasing salinity in the south arm and decreasing salinity in the north arm. This research illustrates that flow modifications within terminal lakes cannot be separated from lake salinity, ecology, management, and economic uses.

  17. How Do Changes to the Railroad Causeway in Utah's Great Salt Lake Affect Water and Salt Flow?

    Science.gov (United States)

    White, James S; Null, Sarah E; Tarboton, David G

    2015-01-01

    Managing terminal lake elevation and salinity are emerging problems worldwide. We contribute to terminal lake management research by quantitatively assessing water and salt flow for Utah's Great Salt Lake. In 1959, Union Pacific Railroad constructed a rock-filled causeway across the Great Salt Lake, separating the lake into a north and south arm. Flow between the two arms was limited to two 4.6 meter wide rectangular culverts installed during construction, an 88 meter opening (referred to locally as a breach) installed in 1984, and the semi porous material of the causeway. A salinity gradient developed between the two arms of the lake over time because the south arm receives approximately 95% of the incoming streamflow entering Great Salt Lake. The north arm is often at, or near, salinity saturation, averaging 317 g/L since 1966, while the south is considerably less saline, averaging 142 g/L since 1966. Ecological and industrial uses of the lake are dependent on long-term salinity remaining within physiological and economic thresholds, although optimal salinity varies for the ecosystem and between diverse stakeholders. In 2013, Union Pacific Railroad closed causeway culverts amid structural safety concerns and proposed to replace them with a bridge, offering four different bridge designs. As of summer 2015, no bridge design has been decided upon. We investigated the effect that each of the proposed bridge designs would have on north and south arm Great Salt Lake elevation and salinity by updating and applying US Geological Survey's Great Salt Lake Fortran Model. Overall, we found that salinity is sensitive to bridge size and depth, with larger designs increasing salinity in the south arm and decreasing salinity in the north arm. This research illustrates that flow modifications within terminal lakes cannot be separated from lake salinity, ecology, management, and economic uses.

  18. Great Salt Lake Microbial Communities: The Foundation of a Terminal Lake Ecosystem

    Science.gov (United States)

    Baxter, B. K.; Acord, M.; Riddle, M. R.; Avery, B.

    2006-12-01

    Great Salt Lake (GSL) is a natural hypersaline ecosystem and a terminal lake of substantial size. The dramatic fluctuation in water levels and salinity creates an ecological backdrop selective for organisms with a high degree of adaptability. At the macro level, the biodiversity of the GSL ecosystem is simple, due to the limitations of an extreme saline environment: Birds eat the two invertebrates of the lake, and the invertebrates eat phytoplankton. However, analysis of the microbial level reveals an enormous diversity of species interacting with one another and the ecosystem as a whole. Our cultivation, biochemical tests, microscopy and DNA sequencing yielded data on dozens of isolates. These data demonstrate novel species, and possibly genera, living in the lake. In addition, we have discovered viruses (bacteriophage) that prey on the microorganisms. Preliminary data on bacteria dwelling in the gut of the brine shrimp, Artemia franciscana, link these prokaryotic organisms to the food chain for the first time. All of these results taken together open the door for the discussion of the significance of the microbial level of terminal lake ecosystem, particularly in light of lake water contamination and bioremediation possibilities.

  19. 77 FR 56608 - Designation for the Pocatello, ID; Evansville, IN; and Salt Lake City, UT Areas

    Science.gov (United States)

    2012-09-13

    ... Designation for the Pocatello, ID; Evansville, IN; and Salt Lake City, UT Areas AGENCY: Grain Inspection....... 10/1/2012 9/30/2015 Ohio Valley Evansville, IN (812) 423-9010... 10/1/2012 9/30/2015 Utah Salt Lake...

  20. Effect of Dried Lake Salt (Kanwa) on Lipid profile and Heart ...

    African Journals Online (AJOL)

    Peripatum cardiomyopathy is a devastating form of cardiac failure affecting women mainly in their last month of pregnancy or early postpartum with high incidence in Northern Nigeria where the consumption of dried lake salt postpartum is high. The current work was designed to study the effect of dried lake salt on lipid ...

  1. Geochemistry and Mineralogy of Western Australian Salt Lake Sediments: Implications for Meridiani Planum on Mars.

    Science.gov (United States)

    Ruecker, A; Schröder, C; Byrne, J; Weigold, P; Behrens, S; Kappler, A

    2016-07-01

    Hypersaline lakes are characteristic for Western Australia and display a rare combination of geochemical and mineralogical properties that make these lakes potential analogues for past conditions on Mars. In our study, we focused on the geochemistry and mineralogy of Lake Orr and Lake Whurr. While both lakes are poor in organic carbon (Lake Orr and from 5.4 to 6.3 in Lake Whurr sediments. Lake Whurr sediments were dominated by orange and red sediment zones in which the main Fe minerals were identified as hematite, goethite, and tentatively jarosite and pyrite. Lake Orr was dominated by brownish and blackish sediments where the main Fe minerals were goethite and another paramagnetic Fe(III)-phase that could not be identified. Furthermore, a likely secondary Fe(II)-phase was observed in Lake Orr sediments. The mineralogy of these two salt lakes in the sampling area is strongly influenced by events such as flooding, evaporation, and desiccation, processes that explain at least to some extent the observed differences between Lake Orr and Lake Whurr. The iron mineralogy of Lake Whurr sediments and the high salinity make this lake a suitable analogue for Meridiani Planum on Mars, and in particular the tentative identification of pyrite in Lake Whurr sediments has implications for the interpretation of the Fe mineralogy of Meridiani Planum sediments. Western Australia-Salt lakes-Jarosite-Hematite-Pyrite-Mars analogue. Astrobiology 16, 525-538.

  2. Analysis of Summer Ozone Concentration in the Salt Lake Valley

    Science.gov (United States)

    Long, Katherine Ansley

    Observations and analyses of ozone concentrations and near-surface wind are examined during the latter half of June 2015 when the highest ozone levels of the 2015 summer were observed in the urban areas of northern Utah referred to locally as the Wasatch Front. A novel mix of ozone observations from sensors at fixed sites as well as mobile platforms (vehicles, light rail car, and news helicopter) help to define the spatiotemporal distribution of ozone along the Wasatch Front and the nearby Great Salt Lake. The ozone and wind observations are assimilated separately using a two-dimensional variational analysis system to obtain ozone and 10-m wind analyses at 1-km horizontal resolution every hour to determine the best representation of ozone distribution throughout the region. Two case studies are used to illustrate the diurnal evolution and transportation of ozone concentrations relative to local wind circulations driven primarily by lake-land and mountain-valley thermal contrasts. Ozone pollution roses at the fixed sensor locations for day and night periods and composites of the 1-km resolution analyses during the 15-day period as a function of time of day help to define common diurnal patterns. This study provides information on how ozone is distributed throughout the region and indicates that areas of high ozone concentrations are a function of the complex interaction of thermal flows in urban, rural, and lake boundary layers.

  3. 78 FR 6832 - Notice of Mailing Address Change for the Utah State Office, Salt Lake City, UT

    Science.gov (United States)

    2013-01-31

    ... Bureau of Land Management Notice of Mailing Address Change for the Utah State Office, Salt Lake City, UT... of Land Management (BLM), Utah State Office, in Salt Lake City, Utah, will be changing from P.O. Box 45155-0155 to 440 West 200 South, Suite 500, Salt Lake City, Utah 84101-1345. The proposed date will be...

  4. Analysis of seasonal characteristics of Sambhar Salt Lake, India, from digitized Space Shuttle photography

    Science.gov (United States)

    Lulla, Kamlesh P.; Helfert, Michael R.

    1989-01-01

    Sambhar Salt Lake is the largest salt lake (230 sq km) in India, situated in the northwest near Jaipur. Analysis of Space Shuttle photographs of this ephemeral lake reveals that water levels and lake basin land-use information can be extracted by both the digital and manual analysis techniques. Seasonal characteristics captured by the two Shuttle photos used in this study show that additional land use/cover categories can be mapped from the dry season photos. This additional information is essential for precise cartographic updates, and provides seasonal hydrologic profiles and inputs for potential mesoscale climate modeling. This paper extends the digitization and mensuration techniques originally developed for space photography and applied to other regions (e.g., Lake Chad, Africa, and Great Salt Lake, USA).

  5. Salt Lake Community College Veterans Services: A Model of Serving Veterans in Higher Education

    Science.gov (United States)

    Ahern, Aaron; Foster, Michael; Head, Darlene

    2015-01-01

    This chapter outlines the birth and growth of a veterans' program in Salt Lake City, Utah, and discusses next steps in spurring additional innovations and advancements to improve service for student veterans in community colleges.

  6. Seepage study of six canals in Salt Lake County, Utah, 1982-1983

    Science.gov (United States)

    Herbert, L.R.; Cruff, R.W.; Waddell, K.M.

    1985-01-01

    A study of selected reaches of the Utah and Salt Lake, Utah Lake Distributing, Provo Reservoir, Draper Irrigation, East Jordan, and Jordan and Salt Lake City Canals in Salt Lake County, Utah, was made to determine gains or losses of flow in those reaches. Three to five sets of seepage measurements were made on each canal during 1982 or 1983. Adjustments for fluctuations in flow were made from information obtained from water-stage recorders operated at selected locations during the time of each seepage run.The study showed an overall net loss of about 9.5 cubic feet per second in the Utah and Salt Lake Canal, 11.0 cubic feet per second in the Utah Lake Distributing canal, 20.5 cubic feet per second in the Provo Reservoir canal, 1.5 cubic feet per second in the Draper Irrigation Canal, and 4.0 cubic feet per second in the East Jordan canal. It also showed a net gain of about 6.0 cubic feet per second in the Jordan and Salt Lake City Canal. The gains and losses are attributed primarily to the relation of the canals to the depth of the water table near the canals.

  7. Added value from 576 years of tree-ring records in the prediction of the Great Salt Lake level

    Science.gov (United States)

    Robert R. Gillies; Oi-Yu Chung; S.-Y. Simon Wang; R. Justin DeRose; Yan Sun

    2015-01-01

    Predicting lake level fluctuations of the Great Salt Lake (GSL) in Utah - the largest terminal salt-water lake in the Western Hemisphere - is critical from many perspectives. The GSL integrates both climate and hydrological variations within the region and is particularly sensitive to low-frequency climate cycles. Since most hydroclimate variable records cover...

  8. Tree-ring reconstruction of the level of Great Salt Lake, USA

    Science.gov (United States)

    R. Justin DeRose; Shih-Yu Wang; Brendan M. Buckley; Matthew F. Bekker

    2014-01-01

    Utah's Great Salt Lake (GSL) is a closed-basin remnant of the larger Pleistocene-age Lake Bonneville. The modern instrumental record of the GSL-level (i.e. elevation) change is strongly modulated by Pacific Ocean coupled ocean/atmospheric oscillations at low frequency, and therefore reflects the decadalscale wet/dry cycles that characterize the region. A within-...

  9. Microbial Diversity of the Hypersaline Sidi Ameur and Himalatt Salt Lakes of the Algerian Sahara

    OpenAIRE

    Boutaiba, Saad; Hacene, Hocine; Bidle, Kelly A.; Maupin-Furlow, Julie A.

    2011-01-01

    Microbial populations within hypersaline lakes often exhibit high activities of photosynthesis, dissimilatory sulphate reduction and other processes and, thus, can have profound impacts on biogeochemical cycles of carbon, nitrogen, sulphur and other important elements within arid lands. To further understand these types of ecosystems, the physicochemical and biological properties of Sidi Ameur and Himalatt Salt Lakes in the Algerian Sahara were examined and compared. Both lakes were relativel...

  10. Arcellacea (testate amoebae) as bio-indicators of road salt contamination in lakes.

    Science.gov (United States)

    Roe, Helen M; Patterson, R Timothy

    2014-08-01

    Winter deicing operations occur extensively in mid- to high-latitude metropolitan regions around the world and result in a significant reduction in road accidents. Deicing salts can, however, pose a major threat to water quality and aquatic organisms. In this paper, we examine the utility of Arcellacea (testate amoebae) for monitoring lakes that have become contaminated by winter deicing salts, particularly sodium chloride. We analysed 50 sediment samples and salt-related water property variables (chloride concentrations; conductivity) from 15 lakes in the Greater Toronto Area and adjacent areas of southern Ontario, Canada. The sampled lakes included lakes in proximity to major highways and suburban roads and control lakes in forested settings away from road influences. Samples from the most contaminated lakes, with chloride concentrations in excess of 400 mg/l and conductivities of >800 μS/cm, were dominated by species typically found in brackish and/or inhospitable lake environments and by lower faunal diversities (lowest Shannon diversity index values) than samples with lower readings. Q-R-mode cluster analysis and detrended correspondence analysis (DCA) resulted in the recognition of four assemblage groupings. These reflect varying levels of salt contamination in the study lakes, along with other local influences, including nutrient loading. The response to nutrients can, however, be isolated if the planktic eutrophic indicator species Cucurbitella tricuspis is removed from the counts. The findings show that the group has considerable potential for biomonitoring in salt-contaminated lakes, and their presence in lake sediment cores may provide significant insights into long-term benthic community health, which is integral for remedial efforts.

  11. Holiday CO2: Inference from the Salt Lake City data

    Science.gov (United States)

    Ryoo, J.; Fung, I. Y.; Ehleringer, J. R.; Stephens, B. B.

    2013-12-01

    A network of high-frequency CO2 sensors has been established in Salt Lake City (SLC), Utah (http://co2.utah.edu/), and the annual/monthly pattern of CO2 variability is consistent with a priori estimates of CO2 fluxes (McKain et al., 2012). Here we ask if short-term changes in anthropogenic sources can be detected, and present a case study of Thanksgiving holiday, when traffic and energy use patterns are expected to be different from that during the rest of the month. CO2 mole fraction is much higher during the Thanksgiving holidays than the other days in November 2008 for all 5 sites in SLC, and a similar pattern is found in other years. Taking into account that the wind speed is relatively low in downtown SLC compared to the other SLC sites, the downtown site is further investigated to minimize the meteorological influence on CO2. In order to understand the relative contributions to the high level of CO2 during the Thanksgiving holidays, we carried out a multiple linear regression (MLR) analysis of the rate of CO2 change against various sources. Mobile CO2 sources are assumed to be proportional to local traffic data and residential CO2 sources are assumed to depend exponentially on temperature. Vulcan data were used to specify the other anthropogenic sources (commercial, industrial, nonroad, electricity, aircraft, and cement). The MLR analysis shows that during the Thanksgiving holidays CO2 contributions from residential and commercial CO2 are larger than that during the rest of November, and mobile sources represent only a relatively small contribution. The study demonstrates the feasibility of detecting changes in urban source contributions using high-frequency measurements in combination with daily PBL height and local traffic volume data.

  12. Halomonas xiaochaidanensis sp. nov., isolated from a salt lake sediment.

    Science.gov (United States)

    Liu, Wen; Zhang, Guojing; Xian, Wendong; Yang, Jian; Yang, Lingling; Xiao, Min; Jiang, Hongchen; Li, Wen-Jun

    2016-10-01

    A short-rod-shaped moderately halophilic bacterium, designated CUG 00002(T), was isolated from the sediment of Xiaochaidan salt lake in Qinghai Province, China by using R2A medium. The cells were Gram-staining negative, aerobic, forming creamy and circular colonies with diameters of 2-3 mm on R2A agar when incubated at 30 °C for 3 days. 16S rRNA gene-based phylogenetic analysis indicated that strain CUG 00002(T) belonged to the genus Halomonas in the class Gammaproteobacteria, showing highest sequence similarity of 97.1 and 96.7 % to Halomonas mongoliensis Z-7009(T) (=DSM 17332=VKM B2353) and Halomonas shengliensis SL014B-85(T) (=CGMCC 1.6444(T)=LMG 23897(T)), respectively. The predominant isoprenoid quinone was ubiquinone-9 (Q9), and the major fatty acids were C16:0, summed feature 3 (comprising C16:1 ω7c and/or C16:1 ω6c) and summed feature 8 (comprising C18:1 ω7c or C18:1 ω6c). The genomic DNA G+C content of strain CUG 00002(T) was 61.8 mol%. The above characteristics were consistent with the placement of the organism in the genus Halomonas. The level of DNA-DNA relatedness between CUG 00002(T) and its most closely related strain H. mongoliensis Z-7009(T) was 41.0 ± 1.6 %. Based on the results of phenotypic, phylogenetic and biochemical analyses, strain CUG 00002(T) represents a novel species of the genus Halomonas, for which the name Halomonas xiaochaidanensis sp. nov. is proposed. The type strain is CUG 00002(T) (=CCTCC AB 2014152(T)=KCTC 42685(T)).

  13. Quality and sources of ground water used for public supply in Salt Lake Valley, Salt Lake County, Utah, 2001

    Science.gov (United States)

    Thiros, Susan A.; Manning, Andrew H.

    2004-01-01

    Ground water supplies about one-third of the water used by the public in Salt Lake Valley, Utah. The occurrence and distribution of natural and anthropogenic compounds in ground water used for public supply in the valley were evaluated. Water samples were collected from 31 public-supply wells in 2001 and analyzed for major ions, trace elements, radon, nutrients, dissolved organic carbon, methylene blue active substances, pesticides, and volatile organic compounds. The samples also were analyzed for the stable isotopes of water (oxygen-18 and deuterium), tritium, chlorofluorocarbons, and dissolved gases to determine recharge sources and ground-water age.Dissolved-solids concentration ranged from 157 to 1,280 milligrams per liter (mg/L) in water from the 31 public-supply wells. Comparison of dissolved-solids concentration of water sampled from the principal aquifer during 1988-92 and 1998-2002 shows a reduction in the area where water with less than 500 mg/L occurs. Nitrate concentration in water sampled from 12 of the 31 public-supply wells was higher than an estimated background level of 2 mg/L, indicating a possible human influence. At least one pesticide or pesticide degradation product was detected at a concentration much lower than drinking-water standards in water from 13 of the 31 wells sampled. Chloroform was the most frequently detected volatile organic compound (17 of 31 samples). Its widespread occurrence in deeper ground water is likely a result of the recharge of chlorinated public-supply water used to irrigate lawns and gardens in residential areas of Salt Lake Valley.Environmental tracers were used to determine the sources of recharge to the principal aquifer used for public supply in the valley. Oxygen-18 values and recharge temperatures computed from dissolved noble gases in the ground water were used to differentiate between mountain and valley recharge. Maximum recharge temperatures in the eastern part of the valley generally are below the range

  14. Brine Shrimp Ecology In The Great Salt Lake, Utah

    OpenAIRE

    Wurtsbaugh, Wayne A.

    1995-01-01

    Hypersaline lakes are noted for their simple communities which facilitate understanding ecological interactions (Williams et al. 1990; Wurtsbaugh 1992; Jellison and Melack 1988). Nevertheless, we still cannot easily predict how environmental changes will effect the population dynamics in these lakes, at least in part because even these simple ecosystems may be more complex than we .realize. Many hypersaline lakes are dominated by the brine shrimp Artemia spp. The production of brine shrimp is...

  15. DIVERSITY OF CULTIVABLE MICROORGANISMS IN THE EASTERN PART OF URMIA SALT LAKE, IRAN

    Directory of Open Access Journals (Sweden)

    Fereshteh Jookar Kashi

    2014-08-01

    Full Text Available In this study we employed culture techniques to study microbial diversity in Urmia Lake, a hypersaline lake in northwest of Iran. Water, soil and salt samples were taken from the Eastern part of Urmia Salt Lake in September 2011. A total of 11 water samples and 30 soil and salt samples were taken from 41 sites in the Lake. Bacterial isolates were cultured on different growth media and taxonomically affiliated based on their 16S rDNA gene sequence. Three hundred bacterial isolates were obtained from samples collected. Of these, 53 bacterial isolates were selected for sequencing and phylogenetic analysis, based on their growth characteristics and colony morphology. Results showed that these 53 isolates represented 39 species, belonging to 18 genera (Bacillus, Oceanobacillus, Thalassobacillus, Planomicrobium, Halobacillus, Planococcus, Terribacillus, Staphylococcus, Piscibacillus, Virgibacillus, Gracilibacillus, Ornithinibacillus, Halomonas, Pseudomonas, Providencia, Salicola, Psychrobacter, Kocuria and they were from 9 families (Bacillaceae, Planococcaceae, Staphylococcaceae, Halomonadaceae, Pseudomonadaceae, Enterobacteriaceae, Moraxellaceae, Alteromonadaceae, Micrococcaceae pertaining to three phyla (Actinobacteria 1.8%, Firmicutes 78.6%, Proteobacteria 21.4%. The present study showed that Urmia Lake is a rich source for moderately halophilic and halotolerant bacteria. The phylogenetic analysis of sequences from Urmia Lake had some common 16S rDNA sequences from other hypersaline lakes previously reported.

  16. Jeotgalicoccus halophilus sp. nov., isolated from salt lakes.

    Science.gov (United States)

    Liu, Wen-Yan; Jiang, Lin-Lin; Guo, Chun-Jing; Yang, Su Sheng

    2011-07-01

    Two slightly halophilic bacterial strains, C1-52(T) and YD-9, were isolated from Daban and Aiding salt lakes in Xinjiang, China, respectively. The isolates were gram-positive, non-endospore-forming, non-motile, facultatively anaerobic cocci. Colonies were pale yellow, and a light pink, diffusible pigment was produced after a few additional days of incubation. The isolates grew optimally with 2-3 % (w/v) NaCl, at pH 7.5 and at 30-35 °C. The peptidoglycan type was L-Lys-Gly(3-4)-L-Ala(Gly). The menaquinones were MK-7 (83.2 %) and MK-6 (16.8 %). The major fatty acids (>10 %) were anteiso-C(15 : 0) and iso-C(15 : 0). The DNA G+C content of strains C1-52(T) and YD-9 was 41.2 and 41.0 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains C1-52(T) and YD-9 were closely related to Jeotgalicoccus psychrophilus YKJ-115(T) (98.0 and 97.1 % 16S rRNA gene sequence similarity, respectively), followed by Jeotgalicoccus halotolerans YKJ-101(T) (97.1 and 96.8 %). Strains C1-52(T) and YD-9 shared, respectively, 20 and 11 % DNA-DNA relatedness with J. halotolerans JCM 11198(T) and 8 and 13 % with J. psychrophilus JCM 11199(T). DNA-DNA relatedness between the isolates was 91 %. On the basis of phenotypic and phylogenetic distinctiveness, strains C1-52(T) and YD-9 belonged to the same species, which should be placed in the genus Jeotgalicoccus as a novel species. The name Jeotgalicoccus halophilus sp. nov. is proposed, with the type strain C1-52(T) ( = CGMCC 1.8911(T)  = NBRC 105788(T)).

  17. Streptomyces lonarensis sp. nov., isolated from Lonar Lake, a meteorite salt water lake in India.

    Science.gov (United States)

    Sharma, Trupti K; Mawlankar, Rahul; Sonalkar, Vidya V; Shinde, Vidhya K; Zhan, Jing; Li, Wen-Jun; Rele, Meenakshi V; Dastager, Syed G; Kumar, Lalitha Sunil

    2016-02-01

    A novel alkaliphilic actinomycete, strain NCL716(T), was isolated from a soil sample collected from the vicinity of Lonar Lake, an alkaline salt water meteorite lake in Buldhana district of Maharashtra State in India. The strain was characterised using a polyphasic taxonomic approach which confirmed that it belongs to the genus Streptomyces. Growth was observed over a pH range of 7-11 at 28 °C. The cell wall was found to contain LL-diaminopimelic acid and traces of meso-diaminopimelic acid. The major fatty acid components were identified as iso-C16:0 (46.8 %), C17:1 (12.4 %), anteiso-C15:0 (5.1 %) and anteiso-C17:1 (4.8 %). The major polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylinositol. The major menaquinones were determined to be MK-9 (H6) (70.3 %), MK-9 (H4) (15.5 %) and MK-9 (H8) (7.2 %). The G+C content of the DNA of the type strain was determined to be 71.4 mol %. The 16S rRNA gene sequence has been deposited in GenBank with accession number FJ919811. Although the 16S rRNA gene sequence analysis revealed that strain NCL716(T) shares >99 % similarity with that of Streptomyces bohaiensis strain 11A07(T), DNA-DNA hybridization revealed only 33.2 ± 3.0 % relatedness between them. Moreover, these two strains can be readily distinguished by some distinct phenotypic characteristics. Hence, on the basis of phenotypic and genetic analyses, it is proposed that strain NCL716(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces lonarensis sp. nov., is proposed. The type strain is NCL 716(T) (=DSM 42084(T) = MTCC 11708(T) = KCTC 39684(T)).

  18. Speciation of cadmium mixed ligand complexes in salt water lakes ...

    African Journals Online (AJOL)

    Amalgam voltammetry has been used to study heavy metal interaction in model lake water in KNO3 at 23 oC at concentration levels of genuine lake water. The hanging drop amalgam electrode was prepared in situ before exchanging the medium for the sample solution. Half-wave potentials at two metal ion concentrations ...

  19. Remote Sensing as a Tool to Track Algal Blooms in the Great Salt Lake, Utah, USA

    Science.gov (United States)

    Bradt, S. R.; Wurtsbaugh, W. A.; Naftz, D.; Moore, T.; Haney, J.

    2006-12-01

    The Great Salt Lake is a large hypersaline, terminal water body in northern Utah, USA. The lake has both a significant economic importance to the local community as a source of brine shrimp and mineral resources, as well as, an ecological importance to large numbers of migratory waterfowl. Due to nutrient input from sewage treatment plants, sections of the Great Salt Lake are subjected to highly eutrophic conditions. One of the main tributaries, Farmington Bay, experiences massive blooms of cyanobacteria which can reach concentrations in excess of 300 mg l-1 in the bay. Effects of these blooms can be observed stretching into the rest of the lake. The detrimental outcomes of the blooms include unsightly scums, foul odor and the danger of cyanobacterial toxins. While the blooms have an obvious effect on Farmington Bay, it is quite possible that the cyanobacteria impact a much wider area of the lake as currents move eutrophic water masses. Of particular interest is the reaction of brine shrimp to the plumes of cyanobacteria-rich water leaving Farmington Bay. We are employing remote sensing as a tool to map the distribution of algae throughout the lake and produce lake-wide maps of water quality on a regular basis. On-lake reflectance measurements have been coupled with MODIS satellite imagery to produce a time series of maps illustrating changes in algal distribution. The successes and shortcomings of our remote sensing technique will be a central topic of this presentation.

  20. Microbial Diversity of the Hypersaline Sidi Ameur and Himalatt Salt Lakes of the Algerian Sahara.

    Science.gov (United States)

    Boutaiba, Saad; Hacene, Hocine; Bidle, Kelly A; Maupin-Furlow, Julie A

    2011-10-01

    Microbial populations within hypersaline lakes often exhibit high activities of photosynthesis, dissimilatory sulphate reduction and other processes and, thus, can have profound impacts on biogeochemical cycles of carbon, nitrogen, sulphur and other important elements within arid lands. To further understand these types of ecosystems, the physicochemical and biological properties of Sidi Ameur and Himalatt Salt Lakes in the Algerian Sahara were examined and compared. Both lakes were relatively neutral in pH (7.2 to 7.4) and high in salt, at 12% and 20 % (w/v) salinity for Himalatt and Sidi Ameur Lakes, respectively, with dominant ions of sodium and chloride. The community compositions of microbes from all three domains (Bacteria, Archaea and Eukarya) were surveyed through the use of 16S and 18S ribosomal gene amplification and clone library clustering using amplified ribosomal DNA restriction analysis (ARDRA) in conjunction with DNA sequencing and analysis. A high level of microbial diversity, particularly among the bacteria of the Himalatt Salt Lake and archaea of Sidi Ameur Lake, was found within these environments. Representatives from all known halophilic bacterial phyla as well as 6 different genera of halophilic archaea were identified. Moreover, several apparently novel phylotypes among both archaea and bacteria were revealed.

  1. Changes in lake levels, salinity and the biological community of Great Salt Lake (Utah, USA), 1847-1987

    Science.gov (United States)

    Stephens, D.W.

    1990-01-01

    Great Salt Lake is the fourth largest terminal lake in the world, with an area of about 6000 square kilometers at its historic high elevation. Since its historic low elevation of 1277.52 meters in 1963, the lake has risen to a new historic high elevation of 1283.77 meters in 1986-1987, a net increase of about 6.25 meters. About 60 percent of this increase, 3.72 meters, has occurred since 1982 in response to greater than average precipitation and less than average evaporation. Variations in salinity have resulted in changes in the composition of the aquatic biological community which consists of bacteria, protozoa, brine shrimp and brine flies. These changes were particularly evident following the completion of a causeway in 1959 which divided the lake. Subsequent salinities in the north part of the lake have ranged from 16 to 29 percent and in the south part from 6 to 28 percent. Accompanying the rise in lake elevation from 1982 to 1987 have been large decreases in salinity of both parts of the lake. This has resulted in changes in the biota from obligate halophiles, such as Dunaliella salina and D. viridis, to opportunistic forms such as a blue-green alga (Nodularia spumigena). The distribution and abundance of brine shrimp (Artemia salina) in the lake also have followed closely the salinity. In 1986, when the salinity of the south part of the lake was about 6 percent, a population of brackish-water killifish (Lucania parva) was observed along the shore near inflow from a spring. ?? 1990 Kluwer Academic Publishers.

  2. 78 FR 65356 - Notice of Mailing/Street Address Change for the BLM-Utah West Desert District and Salt Lake Field...

    Science.gov (United States)

    2013-10-31

    ... and Salt Lake Field Offices AGENCY: Bureau of Land Management, Interior. ACTION: Notice. SUMMARY: The mailing/street address for the Bureau of Land Management (BLM), West Desert District and Salt Lake Field Offices will be changing from 2370 South 2300 West, Salt Lake City, UT 84119-2022, to 2370 South Decker...

  3. 76 FR 47613 - Board Meeting: September 13-14, 2011-Salt Lake City, UT; the U.S. Nuclear Waste Technical Review...

    Science.gov (United States)

    2011-08-05

    ... REVIEW BOARD Board Meeting: September 13-14, 2011--Salt Lake City, UT; the U.S. Nuclear Waste Technical... Technical Review Board will hold a public meeting in Salt Lake City, Utah, on Tuesday, September 13, and....m. and will be held at the Little America Hotel; 500 South Main Street; Salt Lake City, Utah 84101...

  4. Contribution of GIS to evaluate surface water pollution by heavy metals: Case of Ichkeul Lake (Northern Tunisia)

    Science.gov (United States)

    Yazidi, Amira; Saidi, Salwa; Ben Mbarek, Nabiha; Darragi, Fadila

    2017-10-01

    The concentrations of nutrients and heavy elements in the surface water of the lake Ichkeul, main wadis which feed directly and thermal springs that flow into the lake, are measured to evaluate these chemical elements. There are used to highlight the interactions between these different aquatic compartments of Ichkeul. All metal concentrations in lake water, except Cu, were lower than the maximum permitted concentration for the protection of aquatic life. The results show that the highest concentrations are located in the eastern and south-eastern part of the lake where the polluted water comes from the lagoon of Bizerte through the wadi Tinja as well as from the city of Mateur through the wadi Joumine. The pollution indices and especially the heavy metal evaluation index (HEI) show high pollution specially located at the mouths of wadis and an increase of heavy metal concentrations, as a result of uncontrolled releases of domestic and industrial wastewater.

  5. Adequacy Assessment of a Universal Salt Iodization Program Two Decades after Its Implementation: A National Cross-Sectional Study of Iodine Status among School-Age Children in Tunisia.

    Science.gov (United States)

    Doggui, Radhouene; El Ati-Hellal, Myriam; Traissac, Pierre; Lahmar, Lilia; El Ati, Jalila

    2016-12-25

    In the framework of a worldwide policy to eliminate iodine deficiency (ID) disorders, universal salt iodization was adopted in Tunisia two decades ago. The present study aims to evaluate this strategy, using both performance and impact indicators. A total of 1560 children, aged 6-12 years, were randomly sampled using a national, two-stage, stratified, cross-sectional cluster survey in 2012. Urinary iodine concentration (UIC) of the subjects, and household salt iodine content, were analyzed. The national median UIC was 220 µg/L (95% confidence interval (CI): 199-241), indicating an acceptable iodine status at the population level. Only 11.4% (95% CI: 8.6-14.9) of the children had UIC 90% of households. Regular monitoring of iodized salt production lines must be strengthened with involvement by producers.

  6. Highland High School Vocational Television; a Salt Lake Schools Exemplary Vocational Program.

    Science.gov (United States)

    Nagle, LaMar C.

    The Highland High School (Salt Lake City, Utah) vocational television production program was designed to provide students with marketable skills in color television studio operation. Among the skills covered in the program were camera set-up and operation, video engineering, production switching, directing, television lighting, audio engineering,…

  7. A STUDY OF THE NEED FOR A JUNIOR COLLEGE IN THE SALT LAKE METROPOLITAN AREA.

    Science.gov (United States)

    SMITH, RALPH B.

    A POPULATION INCREASE OF 71 PERCENT IS EXPECTED IN UTAH BETWEEN 1960 AND 1980. THE GREATEST GROWTH IS EXPECTED IN THE SALT LAKE METROPOLITAN AREA. THE COLLEGE AGE GROUP (18 TO 21 YEARS) WILL INCREASE BY 80 PERCENT BETWEEN 1960 AND 1970. IF CONSERVATIVE ESTIMATES ARE USED, THE PROPOSED JUNIOR COLLEGE COULD EXPECT AN ENROLLMENT OF APPROXIMATELY…

  8. The aspen mortality summit; December 18 and 19, 2006; Salt Lake City, UT

    Science.gov (United States)

    Dale L. Bartos; Wayne D. Shepperd

    2010-01-01

    The USDA Forest Service Rocky Mountain Research Station sponsored an aspen summit meeting in Salt Lake City, Utah, on December 18 and19, 2006, to discuss the rapidly increasing mortality of aspen (Populus tremuloides) throughout the western United States. Selected scientists, university faculty, and managers from Federal, State, and non-profit agencies with experience...

  9. Chemical quality of ground water in Salt Lake Valley, Utah, 1969-85

    Science.gov (United States)

    Waddell, K.M.; Seiler, R.L.; Solomon, D.K.

    1987-01-01

    During 1979-84, 35 wells completed in the principal aquifer in the Salt Lake Valley, Utah, that had been sampled during 1962-67 were resampled to determine if water-quality changes had occurred. The dissolved-solids concentration of the water from 13 of the wells has increased by more than 10 percent since 1962-67.

  10. National Water-Quality Assessment Program: Great Salt Lake basins study unit

    Science.gov (United States)

    Waddell, Kidd M.

    1999-01-01

    The Great Salt Lake Basins NAWQA study will increase the scientific understanding of the factors that influence surface- and ground-water quality. This information will benefit water-resources managers that need, but often lack, the data required to implement effective water-quality management actions and evaluate long-term changes in water quality.

  11. Textural variation within Great Salt Lake algal mounds: Chapter 8.5 in Stromatolites

    Science.gov (United States)

    1976-01-01

    This chapter discusses textural variation within the Great Salt Lake algal mounds. Great Salt Lake algal mounds contain: (1) a framework of non-skeletal, algally induced aragonite precipitates; (2) internal sediment; and (3) inorganic cement. These three elements create a variety of laminated, poorly laminated, and unlaminated internal textures. Interior framework precipitates bear little resemblance to the present living film of the mound surface. Internal texture of the mounds is believed to be largely relict and to have resulted from precipitation by algae different than those presently living at the surface. The most probable cause of local extinction of the algal flora is change in brine salinity. Precipitated blue-green algal structures in ancient rocks may indicate other than normal marine salinity and near shore sedimentation. Extreme variation of internal texture reflects extreme environmental variability typical of closed basin lakes. Recognition of mounds similar to those in the Great Salt Lake can be a first step toward recognition of ancient hyper-saline lake deposits, if such an interpretation is substantiated by consideration of the entire depositional milieu of precipitated algal mounds.

  12. Evolution and Growth Competition of Salt Fingers in Saline Lake with Slight Wind Shear

    Science.gov (United States)

    Yang, Ray-Yeng; Hwung, Hwung-Hweng; Shugan, Igor

    2010-05-01

    Since the discover of double-diffusive convection by Stommel, Arons & Blanchard (1956), 'evidence has accumulated for the widespread presence of double-diffusion throughout the ocean' and for its 'significant effects on global water-mass structure and the thermohaline convection' (Schmitt, 1998). The salt-fingering form of double-diffusion has particularly attracted interest because of salt-finger convection being now widely recognized as an important mechanism for mixing heat and salt both vertically and laterally in the ocean and saline lake. In oceanographic situations or saline lake where salt fingers may be an important mechanism for the transport of heat and salt in the vertical, velocity shears may also be present. Salt finger convection is analogous to Bénard convection in that the kinetic energy of the motions is obtained from the potential energy stored in the unstable distribution of a stratifying component. On the basis of the thermal analogy it is of interest to discover whether salt fingers are converted into two-dimensional sheets by the wind shear, and how the vertical fluxes of heat and salt are changed by the wind shear. Salt finger convection under the effect of steady wind shear is theoretically examined in this paper. The evolution of developing in the presence of a vertical density gradient disturbance and the horizontal Couette flow is considered near the onset of salt fingers in the saline lake under a moderate rate of wind shear. We use velocity as the basic variable and solve the pressure Poisson equation in terms of the associated Green function. Growth competition between the longitudinal rolls (LR) and the transverse rolls (TR), whose axes are respectively in the direction parallel to and perpendicular to the Couette flow, is investigated by the weakly nonlinear analysis of coupled-mode equations. The results show that the TR mode is characterized in some range of the effective Rayleigh number, and that the stability is dominated by

  13. TOURISM PLANNING OPPORTUNITIES FOR THE SALT LAKES OF OCNELE MARI AND OCNIŢA

    Directory of Open Access Journals (Sweden)

    POPESCU ANTOANETA-CARINA

    2012-03-01

    Full Text Available Tourism Planning Opportunities for The Salt Lakes of Ocnele Mari and Ocniţa. Ocnele Mari used to be a popular balneal tourism destination in the Southern region of Romania, Oltenia. Due to the hilly climate and the two balneal establishments of Ocnele Mari and Ocniţa, tourists could find the necessary natural cure factors for rheumatic and cardiovascular diseases. However, the salt from Ocnele Mari was also used for industrial purposes, being extracted through solution mining, which proved to be detrimental to the environment. Salt underground dissolution caused land subsidence and landslide in the area, together with the formation of large salt lakes. Security became an issue, the number of tourists diminished and the balneal equipment became obsolete because of lack of modernization investment. Under these circumstances, on the basis of field work, we have reached the conclusion that a better planning of the resort and of the salt lakes would contribute to the economic development of the region.

  14. Mercury in the Air, Water and Biota at the Great Salt Lake (Utah, USA)

    Science.gov (United States)

    Peterson, C.; Gustin, M. S.

    2008-12-01

    The Great Salt Lake, Utah (USA), is the fourth largest terminal lake on Earth and a stop-over location for 35 million birds on the Pacific Flyway. Recently, the Utah Department of Health and Utah Division of Wildlife Resources issued tissue mercury (Hg) consumption advisories for several species of birds that consume the lake's brine shrimp. Sources of Hg to the lake are the watershed and the atmosphere, and we hypothesized that the chemistry of the air above the Great Salt Lake would facilitate atmospheric deposition of Hg to the water. Because little information was available on Hg at the Great Salt Lake, and to begin to test this hypothesis, we measured atmospheric elemental (Hg0) and reactive gaseous mercury (RGM) concentrations as well as Hg concentrations in water and brine shrimp five times over a year. Surrogate surfaces and a dry deposition model were applied to estimate the amount of Hg that could be input to the lake surface. We found that atmospheric Hg0 and RGM concentrations were comparable to global ambient background values and those measured in rural areas (respectively). Both Hg0 and RGM exhibited regular diel variability, and no consistent seasonal periods of depleted or elevated values were observed. Based on these findings, local factors are thought to be important in generating elevated RGM concentrations that could be deposited to the lake. Model estimated deposition velocities for RGM to the lake ranged from 0.9 to 3.0 cm sec-1, with an estimated 19 kg of Hg deposited annually. Total Hg and methyl Hg concentrations in surface waters of the lake were consistent throughout the year (3.8 ± 0.8 ng L- 1 and 0.93 ± 0.59 ng L-1, respectively) and not significantly elevated relative to natural waters; however, the percent methyl Hg to total Hg was high (25 to 50%). Brine shrimp Hg concentrations were 384 ppb and had a statistically significant increase from early summer to fall. Based on modeled dry deposition and estimated wet deposition, the

  15. Long-distance flights and high-risk breeding by nomadic waterbirds on desert salt lakes.

    Science.gov (United States)

    Pedler, Reece D; Ribot, Raoul F H; Bennett, Andrew T D

    2018-02-01

    Understanding and conserving mobile species presents complex challenges, especially for animals in stochastic or changing environments. Nomadic waterbirds must locate temporary water in arid biomes where rainfall is highly unpredictable in space and time. To achieve this they need to travel over vast spatial scales and time arrival to exploit pulses in food resources. How they achieve this is an enduring mystery.  We investigated these challenges in the colonial-nesting Banded Stilt (Cladorhynchus leucocephalus), a nomadic shorebird of conservation concern. Hitherto, Banded Stilts were hypothesized to have only 1-2 chances to breed during their long lifetime, when flooding rain fills desert salt lakes, triggering mass-hatching of brine shrimp. Over 6 years, we satellite tagged 57 individuals, conducted 21 aerial surveys to detect nesting colonies on 14 Australian desert salt lakes, and analyzed 3 decades of Landsat and MODIS satellite imagery to quantify salt-lake flood frequency and extent. Within days of distant inland rainfall, Banded Stilts flew 1,000-2,000 km to reach flooded salt lakes. On arrival, females laid over half their body weight in eggs. We detected nesting episodes across the species' range at 7 times the frequency reported during the previous 80 years. Nesting colonies of thousands formed following minor floods, yet most were subsequently abandoned when the water rapidly evaporated prior to egg hatching. Satellite imagery revealed twice as many flood events sufficient for breeding-colony initiation as recorded colonies, suggesting that nesting at remote sites has been underdetected. Individuals took risk on uncertain breeding opportunities by responding to frequent minor flood events between infrequent extensive flooding, exemplifying the extreme adaptability and trade-offs of species exploiting unstable environments. The conservation challenges of nest predation by overabundant native gulls and anthropogenic modifications to salt lakes filling

  16. THE EVOLUTION OF THE SALT LAKES FROM OCNA ŞUGATAG BETWEEN RISK AND CAPITALIZATION

    Directory of Open Access Journals (Sweden)

    G. ŞERBAN

    2015-10-01

    Full Text Available The diapir anticline microdepression of Ocna Şugatag underwent an accelerated transformation immediately after the end of salt mining (at the beginning of the 1960s. During this period of over 50 years of evolution, lake basins formed and disappeared, either naturally, in small sinkholes, or mostly due to the collapse of salt mine adits or chambers, which led to the creation of large-sized lake basins. There is an accelerated dynamics of these basins, as indicated by the sliding of part of the banks at a pace of 0.5-1.5 meters/year. The collapse of the mines is far from over, because the largest mines (Mihai and Dragoş are partly affected and the pillars supporting the ceiling of the adits have a small diameter. Given the present conditions, when the underground brine is used for bathing and treatment purposes, in short time it is possible that new lakes emerge, even larger than the already existing ones. From the point of view of the lake potential, there are important differences, according to the degree of salinity of the water and the more or less accelerated dynamics of the lake basins. The latest two years witnessed an important development of the tourism infrastructure in the analysed area, as well as arrangements of the lakes, which determined a significant increase in the number of tourists searching for outdoor bathing, especially during week-ends.

  17. Speciation of cadmium mixed ligand complexes in salt water lakes

    Directory of Open Access Journals (Sweden)

    John L. Kituyi

    2003-06-01

    Full Text Available Amalgam voltammetry has been used to study heavy metal interaction in model lake water in KNO3 at 23 oC at concentration levels of genuine lake water. The hanging drop amalgam electrode was prepared in situ before exchanging the medium for the sample solution. Half-wave potentials at two metal ion concentrations were measured, one at the actual concentration in the lake while the other at a much lower one. The experimentally determined shifts in half-wave potentials are used to compute several formation constants. At the natural [CO32-] of 0.5 M in the lake, the main contributor to the speciation of cadmium is [Cd(CO3Cl2]2-. At high [Cd2+], the DPASV detects the presence of free Cd2+ ions, hence, potential polluting effect, while the amalgam reports [Cd(CO32Cl] 3- to be dominant above [CO32-] = 0.8 M. There is a variation in the number of complexes detected, their stabilities and percentage distribution in the two methods. Cd2+ ion concentration also affects the number of complexes formed and their stabilities.

  18. Abundance, population structure and production of macro-invertebrate shredders in a Mediterranean brackish lagoon, Lake Ichkeul, Tunisia

    Science.gov (United States)

    Casagranda, Caterina; Dridi, Mohamed Sadok; Boudouresque, Charles François

    2006-02-01

    Abundance, population structure and production of the macro-invertebrates belonging to the functional feeding group of the shredders were studied in the Ichkeul wetland, northern Tunisia, from July 1993 to April 1994. Mean above-ground macrophyte biomass was at a maximum in September followed by a complete breakdown of the Potamogeton pectinatus L. meadow from October onward due to high salinity following an exceptionally dry winter. Only the meadow of Ruppia cirrhosa (Petagna) Grande at Tinja remained in place. Abundance of Gammarus aequicauda (Martynov 1931), Idotea chelipes (Pallas 1766) and Sphaeroma hookeri Leach 1814 was significantly related to the R. cirrhosa biomass. Gammarus aequicauda presented two recruitment periods in spring and autumn, and S. hookeri a third one in winter. The population of I. chelipes was renewed during winter by continued reproduction without any spring generation. Recruitment of all three species was not very successful during the study period. Life span of all three species was between 12 and 15 months. Despite their relatively low biomass and production rate, the shredders have a key function in processing macrophyte matter to different trophic levels through fragmentation and accelerating the decomposition of macrophyte biomass accumulated at the end of the growth season in the Ichkeul lagoon.

  19. Microbial Composition and Preliminary Age of Ooids from the Great Salt Lake, Utah

    Science.gov (United States)

    Piazza, O.; Corsetti, F. A.; Stamps, B. W.; Stevenson, B. S.; Bardsley, A.; Hammond, D. E.; Nunn, H. S.; Berelson, W.; Spear, J. R.

    2016-12-01

    Ooids (laminated coated grains) are common in the geologic record in lacustrine and marine systems. Traditionally interpreted as abiogenic precipitates, recent work suggests that microbial metabolism/byproducts may enhance the calcium carbonate precipitation of some ooids. Thus, the processes that govern ooid formation remain enigmatic, making it difficult to assess their significance as biosigntatures and environmental indicators in modern/ancient environments. The Great Salt Lake, Utah, provides a unique environment to assess the microbial community and growth rate of aragonitic ooids. Ooids collected near Antelope Island were first sieved into coarse, medium, and fine size fractions. One aliquot of each fraction was left untreated and another was washed with ethanol to remove the biomass/biofilm from the exterior. The microbial communities of each aliquot and the surrounding lake water were compared using small subunit rRNA gene sequencing. Since 50% of the ooids studied contain nuclei that were fecal pellets from the Great Salt Lake Artemia (brine shrimp), Artemia pellets were also collected and sequenced to compare to the ooids and the lake water. 228Ra/226Ra of ooids and lake water was measured to evaluate ooid age. Preliminary 228Ra/226Ra results indicate that ooid growth has occurred in the last few decades. Alphaproteobacteria, Deltaproteobacteria, Planctomycetes, and Bacteriodetes were the most abundant bacterial taxa present within ooid samples. In contrast, the lake water was significantly different in composition, dominated by the halophilic Halobacteria (Euryarchaeota). Both the treated and untreated ooids had a microbial community that more closely resembled the composition of the Artemia fecal pellets than the Great Salt Lake water. We conclude that 1) preliminary dating using a novel chronometer suggests very recent ooid formation, and 2) nuclei composition may skew the results when investigating ooid microbial communities.

  20. Microbial community structure and diversity within hypersaline Keke Salt Lake environments.

    Science.gov (United States)

    Han, Rui; Zhang, Xin; Liu, Jing; Long, Qifu; Chen, Laisheng; Liu, Deli; Zhu, Derui

    2017-11-01

    Keke Salt Lake is located in the Qaidamu Basin of China. It is a unique magnesium sulfate-subtype hypersaline lake that exhibits a halite domain ecosystem, yet its microbial diversity has remained unstudied. Here, the microbial community structure and diversity was investigated via high-throughput sequencing of the V3-V5 regions of 16S rRNA genes. A high diversity of operational taxonomic units was detected for Bacteria and Archaea (734 and 747, respectively), comprising 21 phyla, 43 classes, and 201 genera of Bacteria and 4 phyla, 4 classes, and 39 genera of Archaea. Salt-saturated samples were dominated by the bacterial genera Bacillus (51.52%-58.35% relative abundance), Lactococcus (9.52%-10.51%), and Oceanobacillus (8.82%-9.88%) within the Firmicutes phylum (74.81%-80.99%), contrasting with other hypersaline lakes. The dominant Archaea belonged to the Halobacteriaceae family, and in particular, the genera (with an abundance of >10% of communities) Halonotius, Halorubellus, Halapricum, Halorubrum, and Natronomonas. Additionally, we report the presence of Nanohaloarchaeota and Woesearchaeota in Qinghai-Tibet Plateau lakes, which has not been previously documented. Total salinity (especially Mg 2+ , Cl - , Na + , and K + ) mostly correlated with taxonomic distribution across samples. These results expand our understanding of microbial resource utilization within hypersaline lakes and the potential adaptations of dominant microorganisms that allow them to inhabit such environments.

  1. Sapropels in the Great Salt Lake basin: Indicators of massive groundwater-discharge events

    Science.gov (United States)

    Oviatt, C. G.

    2012-12-01

    Two stratigraphic intervals of finely laminated, organic-rich muds (referred to as sapropels), which in places are interbedded with mirabilite (Na2SO4 10H2O) and/or halite (NaCl), are present in cores of sediments from the floor of Great Salt Lake, UT (GSL). The muds vary in thickness, including the interbedded salt, from less than 0.5 m to over 10 m (in the case of the younger sapropel in the north arm of GSL). They contain brine-shrimp cysts and well-defined laminations less than 1 mm thick. Immediately after recovery in cores, the muds are pure black, but they oxidize to brown colors after a few days of exposure to the atmosphere. Organic-carbon contents in the younger sapropel are 3-5 %, and nitrogen percentages range from about 0.2 to 0.4. The sapropels are overlain by muds deposited in shallow hypersaline lakes, and overlie sediments of deep, freshwater lakes. Independent evidence from radiocarbon ages and shoreline chronology indicates that the upper sapropel was deposited while the lake was shallow (less than 25 m deep; average maximum depth of modern GSL is ~10 m; maximum depth of Lake Bonneville is >300 m). The age of the upper sapropel is about 10-11.5 cal ka, and it was deposited immediately following the regression of Lake Bonneville, which filled the basin during marine oxygen-isotope stage 2. The older sapropel directly overlies sediments of a deep lake that is likely correlative with oxygen-isotope stage 6. A hypothesis to explain sapropel deposition is that groundwater that had been stored in mountain aquifers during the high-lake periods was discharged onto the basin floor where it ran into the lake and formed a freshwater cap on the saline water; organic matter that settled to the bottom of the lake from the surface exhausted dissolved oxygen and accumulated on the bottom of the stratified lake. The ages of spring and wetland deposits at numerous localities around the basin are consistent with this hypothesis. This hypothetical cause for sapropel

  2. Design and evaluation of expanded polystyrene geofoam embankments for the I-15 reconstruction project, Salt Lake City, Utah.

    Science.gov (United States)

    2012-10-01

    The report discusses the design and 10-year performance evaluations of Expanded Polystyrene (EPS) Geofoam embankment constructed for the I-15 Reconstruction Project in Salt Lake City, Utah between 1998 and 2002. It contains methods to evaluate the al...

  3. Sedimentary characteristics and depositional model of a Paleocene-Eocene salt lake in the Jiangling Depression, China

    Science.gov (United States)

    Yu, Xiaocan; Wang, Chunlian; Liu, Chenglin; Zhang, Zhaochong; Xu, Haiming; Huang, Hua; Xie, Tengxiao; Li, Haonan; Liu, Jinlei

    2015-11-01

    We studied the sedimentary characteristics of a Paleocene-Eocene salt lake in the Jiangling Depression through field core observation, thin section identification, scanning electron microscopy, and X-ray diffraction analysis. On the basis of sedimentary characteristics we have summarized the petrological and mineralogical characteristics of the salt lake and proposed 9 types of grade IV salt rhythms. The deposition shows a desalting to salting order of halite-argillaceous-mudstone-mud dolostonemud anhydrock-glauberite-halite. The relationship among grade IV rhythms, water salinity and climate fluctuations was analyzed. Based on the analysis of the relationship between boron content and mudstone color and by combining the mineralogy and sedimentary environment characteristics, we propose that the early and late Paleocene Shashi Formation in the Jiangling Depression was a paleolacustrine depositional environment with a high salt content, which is a representation of the shallow water salt lake depositional model. The middle Paleocene Shashi Formation and the early Eocene Xingouzui Formation were salt and brackish sedimentary environments with low salt content in a deep paleolake, which represents a deep salt lake depositional model.

  4. Large branchiopods (Branchiopoda: Anostraca, Notostraca and Spinicaudata from the salt lakes of Algeria

    Directory of Open Access Journals (Sweden)

    Boudjéma SAMRAOUI

    2006-08-01

    Full Text Available We conducted a survey of large branchiopods (Crustacea, Branchiopoda of the major salt lakes of Algeria, particularly those of the eastern Hauts Plateaux. The aim of the survey was to complement a previous survey that focused on the freshwater habitats of Numidia, northeast Algeria. The study revealed 8 species, with one taxon new to Algeria and North Africa (Chirocephalus salinus. Data on the status, phenology and habitats of collected and previously known species are presented for 19 taxa. The distribution of many species has been greatly extended and the co-occurrence of Artemia tunisiana and Branchinella spinosa has been recorded. The studied salt lakes, owing to a large production of fairy shrimps, support a great number of wintering and breeding waterbirds, but are subject to increasing human pressure.

  5. Connections Between Cold Air Pools and Mountain Valley Fog Events in Salt Lake City

    Science.gov (United States)

    Chachere, Catherine N.; Pu, Zhaoxia

    2016-09-01

    The aim of this study is to investigate the connection between cold air pools and fog events in Salt Lake City, Utah, United States. Statistical analyses are conducted using soundings and reported automated surface observing system data from Salt Lake International Airport for the last eighteen cold seasons (October to March, during 1997-2015). A Chi-square test of independence is performed on identified cold air pool, and fog events to determine whether the two events are correlated. Conditional probabilities are then computed to investigate the occurrence of fog, given the presence of a cold pool. These probabilities are compared against that of random fog generation in the mid-winter. It is concluded that the dependence between cold air pools and fog events is statistically significant. The presence of a cold pool makes the formation of fog more likely than random generation.

  6. Chronic toxicity of arsenic to the Great Salt Lake brine shrimp, Artemia franciscana.

    Science.gov (United States)

    Brix, Kevin V; Cardwell, Rick D; Adams, William J

    2003-02-01

    We determined the chronic toxicity of arsenic (sodium arsenate) to the Great Salt Lake brine shrimp, Artemia franciscana. Chronic toxicity was determined by measuring the adverse effects of arsenic on brine shrimp growth, survival, and reproduction under intermittent flow-through conditions. The study commenced with shrimp growth rather than an arsenic effect. This study represents one of the few full life cycle toxicity tests conducted with brine shrimp.

  7. Food Habits of Wintering Waterfowl on the Great Salt Lake, Utah

    OpenAIRE

    Vest, Josh L.; Conover, Michael R.

    2010-01-01

    Two invertebrates, brine shrimp (Artemia franciscana) and brine flies (Ephydridac), occur in great densities in the Great Salt Lake (GSL) but it is unknown whether ducks forage extensively on them during winter or rely on freshwater food. Common Goldeneye (Bucephala clangula), Northern Shoveler (Anas clypeala) and Green-winged Teal (Anas crecca) were collected from the GSL during winters 2004–05 and 2005–06 to evaluate their food habits. Brine shrimp and brine flies comprised more than 70% of...

  8. Large-eddy simulations of a Salt Lake Valley cold-air pool

    Science.gov (United States)

    Crosman, Erik T.; Horel, John D.

    2017-09-01

    Persistent cold-air pools are often poorly forecast by mesoscale numerical weather prediction models, in part due to inadequate parameterization of planetary boundary-layer physics in stable atmospheric conditions, and also because of errors in the initialization and treatment of the model surface state. In this study, an improved numerical simulation of the 27-30 January 2011 cold-air pool in Utah's Great Salt Lake Basin is obtained using a large-eddy simulation with more realistic surface state characterization. Compared to a Weather Research and Forecasting model configuration run as a mesoscale model with a planetary boundary-layer scheme where turbulence is highly parameterized, the large-eddy simulation more accurately captured turbulent interactions between the stable boundary-layer and flow aloft. The simulations were also found to be sensitive to variations in the Great Salt Lake temperature and Salt Lake Valley snow cover, illustrating the importance of land surface state in modelling cold-air pools.

  9. A review on salt lake city, Kolkata, India: Master planning and realization

    Directory of Open Access Journals (Sweden)

    Tošković Dobrivoje

    2008-01-01

    Full Text Available Motivation for construction of Salt Lake City comes from the circumstances characterizing life in Calcutta known by its social, political and cultural activities. Among many problems, the City was faced with poverty and overcrowding. West Bengal Government realized that serious steps have to be taken to resolve the situation. One of the biggest actions of the Government was creation of so called 'NEDECO' Plan for reclamation certain area of the Salted Lakes, followed by the tender for urban planning. The enterprise for water ways Ivan Milutinović was considered the most convenient for both: reclamation and planning. The Conceptualization covers the Main Aims and interests forming plan basis where three factors were selected: urban character, new vs old town, inhabitants and town growth. Follows Existing Land Use Pattern of the Municipal Area. The realization of the Salt Lake Master Plan, as a part of the Municipal Area, is shown through an Overview of Achieved Infrastructure covering Roads, Water Supply, Sewerage, Area Level Storm Water Drainage, Solid Waste Management and, finally, through the Other Municipal Services, such as: Administrative Infrastructure, Health Infrastructure, Greeneries, Water bodies, Socio-Cultural Infrastructure. .

  10. Biostrome communities and mercury and selenium bioaccumulation in the Great Salt Lake (Utah, USA).

    Science.gov (United States)

    Wurtsbaugh, Wayne A; Gardberg, Jodi; Izdepski, Caleb

    2011-09-15

    The Great Salt Lake has a salinity near 150 g/L and is habitat for over 200 species of migratory birds. The diet of many of these birds is dependent on the food web of carbonaceous biostromes (stromatolites) that cover 260 km(2) of the lake's littoral zone. We investigated the biostrome community to understand their production processes and to assess whether they are a potential vector for bioconcentration of high mercury and selenium levels in the lake. The periphyton community of the biostromes was >99% colonial cyanobacteria. Periphyton chlorophyll levels averaged 900 mg m(-2) or nine times that of the lake's phytoplankton. Lake-wide estimates of chlorophyll suggest that their production is about 30% of that of the phytoplankton. Brine fly (Ephydra gracilis) larval densities on the biostromes increased from 7000 m(-2) in June to 20000m(-2) in December. Pupation and adult emergence halted in October and larvae of various instars overwintered at temperatures fly larvae, pupae, and adults were, respectively, 152, 189, 379 and 659 ηg g(-1) dry weight, suggesting that bioconcentration is only moderate in the short food web and through fly developmental stages. However, common goldeneye ducks (Bucephala clangula) that feed primarily on brine fly larvae at the Great Salt Lake had concentrations near 8000 ηg Hg g(-1) dry weight in muscle tissue. Data from a previous study indicated that selenium concentrations in periphyton, brine fly larvae and goldeneye liver tissue were high (1700, 1200 and 24,000 ηg g(-1), respectively) and Hg:Se molar ratios were birds and humans that consume them. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Anthropogenic impacts on the water and salt budgets of St Lucia estuarine lake in South Africa

    Science.gov (United States)

    Lawrie, Robynne A.; Stretch, Derek D.

    2011-05-01

    Lake St Lucia in South Africa is part of a UNESCO World Heritage site and a Ramsar wetland of international importance. Like many coastal wetlands worldwide, anthropogenic activities including catchment land-use changes, water diversions/abstractions, and manipulation of the mouth state have significantly affected its functioning over the past century. Questions concerning its sustainability have motivated a re-evaluation of management decisions made in the past and of options for the future. A model for the water and salt budgets has therefore been used to investigate "what if" scenarios in terms of past anthropogenic interventions. In particular, simulations allow us to evaluate the effects of diverting the Mfolozi river from St Lucia on the functioning of the system and on the occurrence of various water level/salinity states that drive the biological functioning of the ecosystem. In the past, when the St Lucia estuary and the Mfolozi river had a combined inlet, the mouth was predominantly open. The lake had relatively stable water levels but variable salinities that increased during dry conditions due to evaporative losses and saltwater inflows from the sea. If the mouth closed, the Mfolozi flow was diverted into the lake which reduced salinities and maintained or increased water levels. Simulations indicate that without a link to the Mfolozi the lake system would naturally have a mainly closed inlet with lower average salinities but more variable water levels. During dry conditions water levels would reduce and result in desiccation of large areas of the lake as has recently occurred. We conclude that the artificial separation of the St Lucia and Mfolozi inlets underpins the most significant impacts on the water & salt budget of the lake and that its reversal is key to the sustainability of the system.

  12. The sedimentary organic matter from a Lake Ichkeul core (far northern Tunisia): Rock-Eval and biomarker approach

    Science.gov (United States)

    Affouri, Hassène; Sahraoui, Olfa

    2017-05-01

    The vertical distributions of bulk and molecular biomarker composition in samples from a ca. 156 cm sediment core from Lake Ichkeul were determined. Bulk analysis (Rock-Eval pyrolysis, carbonate, lipid extraction) and molecular analysis of saturated fractions were used to characterize the nature, preservation conditions and input of sedimentary organic matter (OM) to this sub-wet lake environment. The sediments are represented mainly by gray-black silty-clay facies where the carbonate (CaCO3) content varies in a range of 10-30% dry sediment. Rock-Eval pyrolysis revealed a homogeneous total organic carbon (TOC) content of ca. 1% sediment, but with down core fluctuation, indicating different anoxic conditions at different depths and material source variation. The values show three periods of relative enrichment, exceeding ca. 1%, at 146-134 cm, 82 cm and 14-0 cm depth. The low Hydrogen Index (HI) values [<119 mg hydrocarbon (HC)/g TOC)] were characteristic of continental Type III OM. The Tmax values in the range 415-420 °C were characteristic of immature OM at an early diagenetic stage. The distributions of n-alkanes (C17 to C34), isoprenoid (iso) alkanes (pristane and phytane), terpanes and steranes showed that the OM is a mixture of marine algal and bacterial source and emergent and floating higher plant origin. In addition, the distributions, as well as several biomarker ratios (n-alkanes, iso-alkanes/n-alkanes), showed that the OM is a mixture of immature and mature. Significant downcore fluctuation was observed in the molecular composition. This indicates intense microbial activity below ca. 50 cm core depth under an anoxic and brackish environment.

  13. Dealing with uncertainty and limited data availability at Lake Tiberias, Israel: Imaging salt diapir using hydrogeological data

    Science.gov (United States)

    Inbar, Nimrod; Rosenthal, Eliyahu; Flexer, Akiva; Möller, Peter; Siebert, Christian; Guttman, Joseph; Yellin-Dror, Annat; Magri, Fabien

    2016-04-01

    Direct data of the Tiberias Basin (TB) deep-seated stratigraphy is limited. Therefore, imaging of suspected underlying salt deposits and their structure is carried out based on salt tectonics theory and shallow seismic data interpretation. It is supported by the geochemistry of surrounding springs and numerical modeling of fluid transport processes within the basin. The Tiberias Basin (TB) is a narrow pull-apart basin located along the Dead Sea Transform. It encompasses Lake Tiberias, which is the largest fresh water lake in the Levant. Saline onshore and offshore springs and seepages are known to contribute considerable amount of salt to the lake endangering its water quality. Since the early 1980's, deep-seated salt deposits are known to exist in the Tiberias basin subsurface as a result of one deep exploration borehole. Interpretation of onshore seismic data at the southern part of the basin reveals its structure and distribution. However, offshore seismic interpretation is debatable and leads to uncertainty regarding the structure and distribution of salt deposits under the lake. The results of the current study suggest that a salt diapir rises under the lake, piercing through the basin-fill adjacent to the western boundary fault of the basin. Chemical analyses show that some springs at the western shore of the Lake contain indications of dissolved halite. In addition, numerical modeling of brine flow suggests that shallow salt domes can allow brine plumes to reach the surface and discharge along the western coast. These results allow imaging and support the hypothesis regarding the occurrences of shallow salt structures in the vicinity of the lake and contribute valuable information for sustainable management of its water.

  14. Organic geochemistry and brine composition in Great Salt, Mono, and Walker Lakes

    Science.gov (United States)

    Domagalski, J.L.; Orem, W.H.; Eugster, H.P.

    1989-01-01

    Samples of Recent sediments, representing up to 1000 years of accumulation, were collected from three closed basin lakes (Mono Lake, CA, Walker Lake, NV, and Great Salt Lake, UT) to assess the effects of brine composition on the accumulation of total organic carbon, the concentration of dissolved organic carbon, humic acid structure and diagenesis, and trace metal complexation. The Great Salt Lake water column is a stratified Na-Mg-Cl-SO4 brine with low alkalinity. Algal debris is entrained in the high density (1.132-1.190 g/cc) bottom brines, and in this region maximum organic matter decomposition occurs by anaerobic processes, with sulfate ion as the terminal electron acceptor. Organic matter, below 5 cm of the sediment-water interface, degrades at a very slow rate in spite of very high pore-fluid sulfate levels. The organic carbon concentration stabilizes at 1.1 wt%. Mono Lake is an alkaline (Na-CO3-Cl-SO4) system. The water column is stratified, but the bottom brines are of lower density relative to the Great Salt Lake, and sedimentation of algal debris is rapid. Depletion of pore-fluid sulfate, near l m of core, results in a much higher accumulation of organic carbon, approximately 6 wt%. Walker Lake is also an alkaline system. The water column is not stratified, and decomposition of organic matter occurs by aerobic processes at the sediment-water interface and by anaerobic processes below. Total organic carbon and dissolved organic carbon concentrations in Walker Lake sediments vary with location and depth due to changes in input and pore-fluid sulfate concentrations. Nuclear magnetic resonance studies (13C) of humic substances and dissolved organic carbon provide information on the source of the Recent sedimentary organic carbon (aquatic vs. terrestrial), its relative state of decomposition, and its chemical structure. The spectra suggest an algal origin with little terrestrial signature at all three lakes. This is indicated by the ratio of aliphatic to

  15. First recorded proliferation of Coolia monotis (Meunier, 1919) in the North Lake of Tunis (Tunisia) correlation with environmental factors.

    Science.gov (United States)

    Armi, Zina; Turki, Souad; Trabelsi, Elbahri; Ben Maiz, Naceur

    2010-05-01

    Coolia monotis is a potentially toxic epiphytic dinoflagellate widespread along the Mediterranean coasts, where it is frequently detected year round at low concentrations. However, it only proliferates recurrently in some localities. The North Lake of Tunis is one of the affected areas in the southwestern part of the Mediterranean Sea. This site is one of the most productive aquatic Tunisian areas (Recreational Fisheries and shellfish collecting). In the south part of this area of study, recurrent C. monotis proliferation (5 x10(5) cells per liter) took place in late spring and early summer of 2006. During this proliferation, the spatial distribution of C. monotis species, phytoplankton community, and abiotic factors were studied. The composition of the phytoplankton community exhibited a clear dominance of dinoflagellates over other genera. We suggest that proliferation development of C. monotis was linked to climatic conditions, water temperature (r = 0.24, p < 0.05) and high concentrations of nitrogenous nutrients, essentially NH(4)(+) (r = 0.18, p < 0.05) and NO(3)(-) (r = 0.21, p < 0.05).

  16. Sources of inflow and nature of redistribution of90Sr in the salt lakes of the Crimea.

    Science.gov (United States)

    Mirzoyeva, N Yu; Arkhipova, S I; Kravchenko, N V

    2017-11-04

    At the first time for the period after the Chernobyl NPP accident the nature of the redistribution of the 90 Sr concentrations in components of the ecosystems of the salt lakes of the Crimea were identified and described. Concentration of 90 Sr in water of the salt lakes depends on the sources of the inflow this radionuclide into aquatic ecosystems and salinity level of lakes water. Until April 2014 the flow of the Dnieper river water through the Northern-Crimean canal was more important factor of contamination of salt lakes of the Crimea by 90 Sr, than atmospheric fallout of this radionuclide after the Chernobyl NPP accident. Concentrations of 90 Sr in water of the salt lakes of the Crimea exceeded 2.4-156.5 times its concentrations in their bottom sediments. The 90 Sr dose commitments to hydrophytes, which were sampled from the salt lakes of the Crimea have not reached values which could impact them during entire the after-accident period. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Feeding spectra of Arctodiaptomus salinus (Calanoida, Copepoda) using fatty acid trophic markers in seston food in two salt lakes in South Siberia (Khakasia, Russia)

    NARCIS (Netherlands)

    Tolomeev, A.; Sushchik, N.N.; Gulati, R.D.; Makhutova, O.N.; Kalacheva, G.S.; Zotina, T.A.

    2010-01-01

    During two vegetation seasons (2004–2005), we compared feeding spectra of Arctodiaptomus salinus (Calanoida, Copepoda) populations inhabiting two neighboring salt lakes, Shira and Shunet, Khakasia, Russia, using fatty acid (FA) trophic markers. Sestonic FA composition in two lakes moderately

  18. A salt diapir-related Mississippi Valley-type deposit: The Bou Jaber Pb-Zn-Ba-F deposit, Tunisia: Fluid inclusion and isotope study

    Science.gov (United States)

    Bouhlel, Salah; Leach, David; Johnson, Craig A.; Marsh, Erin; Salmi-Laouar, Sihem; Banks, David A.

    2016-01-01

    The Bou Jaber Ba-F-Pb-Zn deposit is located at the edge of the Bou Jaber Triassic salt diapir in the Tunisia Salt Diapir Province. The ores are unconformity and fault-controlled and occur as subvertical column-shaped bodies developed in dissolution-collapse breccias and in cavities within the Late Aptian platform carbonate rocks, which are covered unconformably by impermeable shales and marls of the Fahdene Formation (Late Albian–Cenomanian age). The host rock is hydrothermally altered to ankerite proximal to and within the ore bodies. Quartz, as fine-grained bipyramidal crystals, formed during hydrothermal alteration of the host rocks. The ore mineral assemblage is composed of barite, fluorite, sphalerite, and galena in decreasing abundance. The ore zones outline distinct depositional events: sphalerite-galena, barite-ankerite, and fluorite. Fluid inclusions, commonly oil-rich, have distinct fluid salinities and homogenization temperatures for each of these events: sphalerite-galena (17 to 24 wt% NaCl eq., and Th from 112 to 136 °C); ankerite-barite (11 to 17 wt% NaCl eq., and Th from 100 to 130 °C); fluorite (19 to 21 wt% NaCl eq., Th from 140 to 165 °C). The mean temperature of the ore fluids decreased from sphalerite (125 °C) to barite (115 °C) and increased during fluorite deposition (152 °C); then decreased to ∼110 °C during late calcite precipitation. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses of fluid inclusions in fluorite are metal rich (hundreds to thousands ppm Pb, Zn, Cu, Fe) but the inclusions in barite are deficient in Pb, Zn, Cu, Fe. Inclusions in fluorite have Cl/Br and Na/Br ratios of several thousand, consistent with dissolution of halite while the inclusions analysed in barite have values lower than seawater which are indicative of a Br-enriched brine derived from evaporation plus a component of halite dissolution. The salinity of the barite-hosted fluid inclusions is less than obtained

  19. A salt diapir-related Mississippi Valley-type deposit: the Bou Jaber Pb-Zn-Ba-F deposit, Tunisia: fluid inclusion and isotope study

    Science.gov (United States)

    Bouhlel, Salah; Leach, David L.; Johnson, Craig A.; Marsh, Erin; Salmi-Laouar, Sihem; Banks, David A.

    2016-08-01

    The Bou Jaber Ba-F-Pb-Zn deposit is located at the edge of the Bou Jaber Triassic salt diapir in the Tunisia Salt Diapir Province. The ores are unconformity and fault-controlled and occur as subvertical column-shaped bodies developed in dissolution-collapse breccias and in cavities within the Late Aptian platform carbonate rocks, which are covered unconformably by impermeable shales and marls of the Fahdene Formation (Late Albian-Cenomanian age). The host rock is hydrothermally altered to ankerite proximal to and within the ore bodies. Quartz, as fine-grained bipyramidal crystals, formed during hydrothermal alteration of the host rocks. The ore mineral assemblage is composed of barite, fluorite, sphalerite, and galena in decreasing abundance. The ore zones outline distinct depositional events: sphalerite-galena, barite-ankerite, and fluorite. Fluid inclusions, commonly oil-rich, have distinct fluid salinities and homogenization temperatures for each of these events: sphalerite-galena (17 to 24 wt% NaCl eq., and Th from 112 to 136 °C); ankerite-barite (11 to 17 wt% NaCl eq., and Th from 100 to 130 °C); fluorite (19 to 21 wt% NaCl eq., Th from 140 to 165 °C). The mean temperature of the ore fluids decreased from sphalerite (125 °C) to barite (115 °C) and increased during fluorite deposition (152 °C); then decreased to ˜110 °C during late calcite precipitation. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses of fluid inclusions in fluorite are metal rich (hundreds to thousands ppm Pb, Zn, Cu, Fe) but the inclusions in barite are deficient in Pb, Zn, Cu, Fe. Inclusions in fluorite have Cl/Br and Na/Br ratios of several thousand, consistent with dissolution of halite while the inclusions analysed in barite have values lower than seawater which are indicative of a Br-enriched brine derived from evaporation plus a component of halite dissolution. The salinity of the barite-hosted fluid inclusions is less than obtained simply by the

  20. Computer program to simulate the salt balance between the north and south parts of Great Salt Lake, Utah

    Science.gov (United States)

    Waddell, K.M.; Bolke, E.L.

    1975-01-01

    This report presents a computer simulation program that was used by Waddell and Bolke (1973) to predict the salt balance between the north and south parts of Great Salt Lake, Utah, for either existing or modified culvert openings (fig. 1). The development of the program, its accuracy and limitations, are described in the above report, which was prepared as part of a study conducted by the U.S. Geological Survey in cooperation with the Utah Geological and Mineral Survey. Users of this program should consider it an addendum to the report by Waddell and Bolke (1973).Although this program has been tested by its contributor, no warranty, expressed or implied, is made by the contributor or the Government, as to the functioning of the program and related program material, nor shall the fact of distribution constitute any such warranty, and no responsibility is assumed by the contributor or the Government, in connection therewith.The FORTRAN IV program listing (table 1) defines the constants and variables necessary for understanding the mechanics and the output from the program.

  1. Actinomycetes Diversity among rRNA Gene Clones and Cellular Isolates from Sambhar Salt Lake, India

    Directory of Open Access Journals (Sweden)

    A. K. Yadav

    2013-01-01

    Full Text Available The vertical stratification of actinomycetes diversity in Sambhar salt lake (India’s largest salt lake was investigated by using cultivable and uncultivable approaches. The isolates from cultured approaches were clustered on the basis of cultural, morphological, biochemical, and cell wall characteristics, and results were further strengthened by 16S rDNA-RFLP into five major groups. 16S rDNA sequencing of the representative isolates from each clusters was identified as belonging to Streptomyces, Actinopolyspora, Microbispora, Saccharopolyspora, and Actinoplanes genera, while culture independent group was established as Streptomyces (130 clones, 20 OTUs, Micromonospora (96 clones, 7 OTUs, Streptosporangium (79 clones, 9 OTUs, Thermomonospora (46 clones, 8 OTUs, and Dactylosporangium (58 clones, 8 OTUs. The diversity assessment using Shannon and Wiener index was found to be 1.55, 1.52, 1.55, and 1.49 from surface lake water, at depth of 1.5 m, shallow layer of water with algal population, and finally at depth of 2.5 m, respectively. We observed diversity in terms of the species richness as Streptomyces is dominant genus in both culture dependent and culture independent techniques followed by Microbispora (culture dependent methods and Micromonospora (culture independent method genera, respectively.

  2. Mercury and selenium contamination in waterbird eggs and risk to avian reproduction at Great Salt Lake, Utah

    Science.gov (United States)

    Ackerman, Joshua T.; Herzog, Mark P.; Hartman, Christopher A.; Isanhart, John P.; Herring, Garth; Vaughn, Sharon; Cavitt, John F.; Eagles-Smith, Collin A.; Browers, Howard; Cline, Chris; Vest, Josh

    2015-01-01

    The wetlands of the Great Salt Lake ecosystem are recognized regionally, nationally, and hemispherically for their importance as breeding, wintering, and migratory habitat for diverse groups of waterbirds. Bear River Migratory Bird Refuge is the largest freshwater component of the Great Salt Lake ecosystem and provides critical breeding habitat for more than 60 bird species. However, the Great Salt Lake ecosystem also has a history of both mercury and selenium contamination, and this pollution could reduce the health and reproductive success of waterbirds. The overall objective of this study was to evaluate the risk of mercury and selenium contamination to birds breeding within Great Salt Lake, especially at Bear River Migratory Bird Refuge, and to identify the waterbird species and areas at greatest risk to contamination. We sampled eggs from 33 species of birds breeding within wetlands of Great Salt Lake during 2010 ̶ 2012 and focused on American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), Forster’s terns (Sterna forsteri), white-faced ibis (Plegadis chihi), and marsh wrens (Cistothorus palustris) for additional studies of the effects of contaminants on reproduction.

  3. Microbial life in the Lake Medee, the largest deep-sea salt-saturated formation.

    Science.gov (United States)

    Yakimov, Michail M; La Cono, Violetta; Slepak, Vladlen Z; La Spada, Gina; Arcadi, Erika; Messina, Enzo; Borghini, Mireno; Monticelli, Luis S; Rojo, David; Barbas, Coral; Golyshina, Olga V; Ferrer, Manuel; Golyshin, Peter N; Giuliano, Laura

    2013-12-19

    Deep-sea hypersaline anoxic lakes (DHALs) of the Eastern Mediterranean represent some of the most hostile environments on our planet. We investigated microbial life in the recently discovered Lake Medee, the largest DHAL found to-date. Medee has two unique features: a complex geobiochemical stratification and an absence of chemolithoautotrophic Epsilonproteobacteria, which usually play the primary role in dark bicarbonate assimilation in DHALs interfaces. Presumably because of these features, Medee is less productive and exhibits reduced diversity of autochthonous prokaryotes in its interior. Indeed, the brine community almost exclusively consists of the members of euryarchaeal MSBL1 and bacterial KB1 candidate divisions. Our experiments utilizing cultivation and [(14)C]-assimilation, showed that these organisms at least partially rely on reductive cleavage of osmoprotectant glycine betaine and are engaged in trophic cooperation. These findings provide novel insights into how prokaryotic communities can adapt to salt-saturated conditions and sustain active metabolism at the thermodynamic edge of life.

  4. Halotolerant extremophile bacteria from the Great Salt Lake for recycling pollutants in microbial fuel cells

    Science.gov (United States)

    Grattieri, Matteo; Suvira, Milomir; Hasan, Kamrul; Minteer, Shelley D.

    2017-07-01

    The treatment of hypersaline wastewater (approximately 5% of the wastewater worldwide) cannot be performed by classical biological techniques. Herein the halotolerant extremophile bacteria obtained from the Great Salt Lake (Utah) were explored in single chamber microbial fuel cells with Pt-free cathodes for more than 18 days. The bacteria samples collected in two different locations of the lake (Stansbury Bay and Antelope Island) showed different electrochemical performances. The maximum achieved power output of 36 mW m-2 was from the microbial fuel cell based on the sample originated from Stansbury Bay, at a current density of 820 mA m-2. The performances throughout the long-term operation are discussed and a bioelectrochemical mechanism is proposed.

  5. A multi-proxy record of volume in the Great Salt Lake over the Holocene

    Science.gov (United States)

    Nielson, K. E.; Bowen, G. J.; Toney, J. L.; Tarozo, R.; Huang, Y.; Bowen, B.

    2010-12-01

    Continental paleoclimate records for the Holocene are essential for understanding the influence of climate modes on terrestrial settings. Terminal lakes, like the Great Salt Lake, UT (GSL) are particularly well suited for examining changes in water balance in response to large scale climate change. We present records of lipid abundance and hydrogen isotope data; hydrogen and oxygen isotope variability in brine shrimp cysts; carbonate oxygen and carbon isotopes; and variability in mineralogy from reflectance spectrometry in a core spanning 9 to 2 ka bp from the GSL. The isotopic value of lake waters are inferred from the cyst isotope records. The oxygen isotopic composition of cysts decreases slowly by about 2 ‰ from the beginning of the record (approx. 9 ka bp) to about 6 ka, and is highly variable after about 4.5 ka bp. This gradual isotopic decrease suggests increased water input into the GSL up to the Mid-Holocene and more variable inputs after. Some portion of the decrease is likely attributable to a reestablishment of equilibrium with local precipitation sources following the rapid evaporation of Lake Bonneville at the end of the Pleistocene. Carbonate oxygen and carbon isotope ratios co-vary before 5.5 ka and after 4.5 ka, and are anti-correlated between, suggesting a major restructuring of the hydrologic regime in the Mid-Holocene. Distributions of lipid and n

  6. Revisiting the Salt Lake City Olympic scandal: Would the outcome be different today?

    Directory of Open Access Journals (Sweden)

    Mark Dodds

    2016-04-01

    Full Text Available Many international sport organizations face bribery scandals resulting from its event bidding process. The International Olympic Committee (IOC faced this type of scandal with the 2002 Olympic Winter Games. Two members of the Salt Lake City Organizing Committee (SLOC faced 15 criminal charges from providing more than US$1.2 million in cash and gifts to entice IOC members to support its bid. Ultimately both SLOC members were acquitted of all charges. Can a new interpretation of the United States’ anti-bribery law, the Foreign Corrupt Practices Act (FCPA, be effective in preventing similar sport scandals?

  7. Perspective View with Landsat Overlay, Salt Lake City Olympics Venues, Utah

    Science.gov (United States)

    2002-01-01

    The 2002 Winter Olympics are hosted by Salt Lake City at several venues within the city, in nearby cities, and within the adjacent Wasatch Mountains. This computer generated perspective image provides a northward looking 'view from space' that includes all of these Olympic sites. In the south, next to Utah Lake, Provo hosts the ice hockey competition. In the north, northeast of the Great Salt Lake, Ogden hosts curling, and the nearby Snow Basin ski area hosts the downhill events. In between, southeast of the Great Salt Lake, Salt Lake City hosts the Olympic Village and the various skating events. Further east, across the Wasatch Mountains, the Park City area ski resorts host the bobsled, ski jumping, and snowboarding events. The Winter Olympics are always hosted in mountainous terrain. This view shows the dramatic landscape that makes the Salt Lake City region a world-class center for winter sports.This 3-D perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM) and a Landsat 5 satellite image mosaic. Topographic expression is exaggerated four times.For a full-resolution, annotated version of this image, please select Figure 1, below: [figure removed for brevity, see original site] Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and will substantially help in analyzing the large and growing Landsat image archive, managed by the U.S. Geological Survey (USGS).Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60

  8. Prokaryotic diversity in Aran-Bidgol salt lake, the largest hypersaline playa in Iran.

    Science.gov (United States)

    Makhdoumi-Kakhki, Ali; Amoozegar, Mohammad Ali; Kazemi, Bahram; Pašić, Lejla; Ventosa, Antonio

    2012-01-01

    Prokaryotic diversity in Aran-Bidgol salt lake, a thalasohaline lake in Iran, was studied by fluorescence in situ hybridization (FISH), cultivation techniques, denaturing gradient gel electrophoresis (DGGE) of PCR-amplified fragments of 16S rRNA genes and 16S rRNA gene clone library analysis. Viable counts obtained (2.5-4 × 10(6) cells mL(-1)) were similar to total cell abundance in the lake determined by DAPI direct count (3-4×10(7) cells mL(-1)). The proportion of Bacteria to Archaea in the community detectable by FISH was unexpectedly high and ranged between 1:3 and 1:2. We analyzed 101 archaeal isolates and found that most belonged to the genera Halorubrum (55%) and Haloarcula (18%). Eleven bacterial isolates obtained in pure culture were affiliated with the genera Salinibacter (18.7%), Salicola (18.7%) and Rhodovibrio (35.3%). Analysis of inserts of 100 clones from the eight 16S rRNA clone libraries constructed revealed 37 OTUs. The majority (63%) of these sequences were not related to any previously identified taxa. Within this sampling effort we most frequently retrieved phylotypes related to Halorhabdus (16% of archaeal sequences obtained) and Salinibacter (36% of bacterial sequences obtained). Other prokaryotic groups that were abundant included representatives of Haloquadratum, the anaerobic genera Halanaerobium and Halocella, purple sulfur bacteria of the genus Halorhodospira and Cyanobacteria.

  9. Physical Monitoring of Flow Into and Within Great Salt Lake, Utah

    Science.gov (United States)

    Kenney, T. A.; Naftz, D. L.; Perschon, W. C.

    2006-12-01

    Great Salt Lake (GSL) is the hydrologic terminus for the eastern part of the Great Basin. As the largest inland waterbody in the Western United States, GSL plays a critical ecologic role for many migratory bird species. In terms of harvest quantity and quality, the brine shrimp (Artemia) fishery of GSL is among the strongest in the world. The characteristic of GSL as a hydrologic sink amplifies anthropogenic activities throughout the basin, most specifically activities that occur along its eastern and southern shores, the urban corridor of the Wasatch Front. In 1959 GSL was divided into north and south parts by a rock-fill railroad causeway. Since then, an extreme density gradient between the north and south part exists as a result of limited conveyance of water from the south part where more than 95 percent of the total freshwater input occurs (Loving, and others, 2000). To date, little is known about the loading and cycling of various chemical constituents associated with human activities including nutrients, selenium, and mercury. Hydroacoustic technology, specifically acoustic Doppler technology, is currently being used to obtain a better physical understanding of GSL. Since 1999, stratified bi-directional discharge has been measured at the causeway breach with an acoustic Doppler current profiler. From these measurements, net flow components to the north and south have been used to assess the movement of water and salt through the causeway. Low hydraulic gradients and variable backwater conditions at the two largest inflows to GSL required the deployment of in-situ acoustic Doppler velocity meters to accurately compute continuous discharge, critical for constituent loading analyses. These discharge records, computed using the index velocity method, show sensitivity to large wind events that can lead to a complete reversal of flow. Velocity profiles acquired during two multi-day water-quality synoptic sampling runs with acoustic Doppler current profilers have

  10. Composition and secondary formation of fine particulate matter in the Salt Lake Valley: winter 2009.

    Science.gov (United States)

    Kuprov, Roman; Eatough, Delbert J; Cruickshank, Tyler; Olson, Neal; Cropper, Paul M; Hansen, Jaron C

    2014-08-01

    Under the National Ambient Air Quality Standards (NAAQS), put in place as a result of the Clean Air Amendments of 1990, three regions in the state of Utah are in violation of the NAAQS for PM10 and PM2.5 (Salt Lake County, Ogden City, and Utah County). These regions are susceptible to strong inversions that can persist for days to weeks. This meteorology, coupled with the metropolitan nature of these regions, contributes to its violation of the NAAQS for PM during the winter. During January-February 2009, 1-hr averaged concentrations of PM10-2.5, PM2.5, NO(x), NO2, NO, O3, CO, and NH3 were measured. Particulate-phase nitrate, nitrite, and sulfate and gas-phase HONO, HNO3, and SO2 were also measured on a 1-hr average basis. The results indicate that ammonium nitrate averages 40% of the total PM2.5 mass in the absence of inversions and up to 69% during strong inversions. Also, the formation of ammonium nitrate is nitric acid limited. Overall, the lower boundary layer in the Salt Lake Valley appears to be oxidant and volatile organic carbon (VOC) limited with respect to ozone formation. The most effective way to reduce ammonium nitrate secondary particle formation during the inversions period is to reduce NO(x) emissions. However, a decrease in NO(x) will increase ozone concentrations. A better definition of the complete ozone isopleths would better inform this decision. Implications: Monitoring of air pollution constituents in Salt Lake City, UT, during periods in which PM2.5 concentrations exceeded the NAAQS, reveals that secondary aerosol formation for this region is NO(x) limited. Therefore, NO(x) emissions should be targeted in order to reduce secondary particle formation and PM2.5. Data also indicate that the highest concentrations of sulfur dioxide are associated with winds from the north-northwest, the location of several small refineries.

  11. Tunisia: Current Issues

    Science.gov (United States)

    2009-11-19

    Tunisia. AQIM later claimed responsibility for kidnapping two Austrian tourists in Tunisia in February 2008. Algerian and Tunisian authorities have...liberalization with the coming free-trade zone with the EU; and privatization. The textile sector has since shifted to higher quality goods. The tourism sector...between the last quarter of 2008 and the first quarter of 2009. Tourism receipts and 16

  12. Marinimicrobium haloxylanilyticum sp. nov., a new moderately halophilic, polysaccharide-degrading bacterium isolated from Great Salt Lake, Utah

    DEFF Research Database (Denmark)

    Fogh Møller, Mette; Kjeldsen, Kasper Urup; Ingvorsen, Kjeld

    2010-01-01

    A new moderately halophilic, strictly aerobic, Gram-negative bacterium, strain SX15T, was isolated from hypersaline surface sediment of the southern arm of Great Salt Lake (Utah, USA). The strain grew on a number of carbohydrates and carbohydrate polymers such as xylan, starch, carboxymethyl...

  13. 77 FR 13074 - Opportunity for Designation in the Pocatello, ID; Evansville, IN; and Salt Lake City, UT Areas...

    Science.gov (United States)

    2012-03-05

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE Grain Inspection, Packers and Stockyards Administration Opportunity for Designation in the Pocatello, ID; Evansville, IN; and Salt Lake City, UT Areas; Request for Comments on the Official Agencies Servicing These...

  14. Differential Staffing Patterns with Job Analyses and Operational Procedures for Salt Lake City School District Media Centers.

    Science.gov (United States)

    Hodkin, Katherine Story

    Duties of the staff of media centers in the Salt Lake City School District and an analysis of task performances by position are listed. Positions included are: (1) head of the school media center/school media specialist, (2) school media center technician, (3) school media center aide, and (4) student aides. Twenty general district operational…

  15. Heterotrophic denitrification at extremely high salt and pH by haloalkaliphilic Gammaproteobacteria from hypersaline soda lakes

    NARCIS (Netherlands)

    Shapovalova, A.A.; Khijniak, T.V.; Tourova, T.P.; Muyzer, G.; Sorokin, Y.

    2008-01-01

    In this paper we describe denitrification at extremely high salt and pH in sediments from hypersaline alkaline soda lakes and soda soils. Experiments with sediment slurries demonstrated the presence of acetate-utilizing denitrifying populations active at in situ conditions. Anaerobic enrichment

  16. Lateral spread hazard mapping of the northern Salt Lake Valley, Utah, for a M7.0 scenario earthquake

    Science.gov (United States)

    Olsen, M.J.; Bartlett, S.F.; Solomon, B.J.

    2007-01-01

    This paper describes the methodology used to develop a lateral spread-displacement hazard map for northern Salt Lake Valley, Utah, using a scenario M7.0 earthquake occurring on the Salt Lake City segment of the Wasatch fault. The mapping effort is supported by a substantial amount of geotechnical, geologic, and topographic data compiled for the Salt Lake Valley, Utah. ArcGIS?? routines created for the mapping project then input this information to perform site-specific lateral spread analyses using methods developed by Bartlett and Youd (1992) and Youd et al. (2002) at individual borehole locations. The distributions of predicted lateral spread displacements from the boreholes located spatially within a geologic unit were subsequently used to map the hazard for that particular unit. The mapped displacement zones consist of low hazard (0-0.1 m), moderate hazard (0.1-0.3 m), high hazard (0.3-1.0 m), and very high hazard (> 1.0 m). As expected, the produced map shows the highest hazard in the alluvial deposits at the center of the valley and in sandy deposits close to the fault. This mapping effort is currently being applied to the southern part of the Salt Lake Valley, Utah, and probabilistic maps are being developed for the entire valley. ?? 2007, Earthquake Engineering Research Institute.

  17. End-Permian mass extinction caused by high volatile halogenated gases from giant salt lakes?

    Science.gov (United States)

    Lisitsyna, Lidia; Weissflog, Ludwig

    2010-05-01

    Climatic and paleotoxicological processes, which caused mass extinction (ME) approx. 250 Ma ago may also play a decisive role in the present day sixth large-scale ME of species, caused by mankind. The speed with which the currently ME is taking effect is higher by a factor of 1000 than that of 100 years ago (8th UN Conference on Biological Diversity in 2006, Djoghlaf, 2006). The worldwide increasing temperature and dryness incorporated in climate change are already leading to progressive desertification and to an increase in number and surface areas of hyper saline salt lakes, salt lagoons, saline marshlands and sabkhas. Furthermore the predicted sea level rise by approx. 1 m (even up to 6 m according to more recent assumptions) leads to an expansion or new formation of salt ecosystems caused by flooding of coastal areas and hinterland. Particularly in regions with current and/or future semiarid and arid climatic features this will lead, amongst others, to increased emissions of naturally formed phytotoxic VHCs. Additionally, wind and storms will transport large quantities of salt (dust) from surfaces of these parched hyper saline salt ecosystems for uptake in so far unsalinated soils. An example of this is currently apparent in Central Asia, where several hundred thousand metric tons of salt dust are picked up every year from the former sea floor of the drying-up Aral Sea, the Kara-Bogaz-Gol and saline marshlands of Caspian Sea and transported several thousand kilometers [Orlovsky and Orlovsky, 2001]. In combination with increasing temperatures, intensive radiation and increasing input of man-made pollutants, desert areas of Central Asia are expanding ever faster. In this context it has to be borne in mind that today's observations only refer to a timeframe of a few years or decades. The developments at end-Permian, on the other hand, encompass approx. 100,000 years. In this respect, the current state of art does not permit any definite statements as to what

  18. Simulation of Saline Groundwater Resources Surrounding Salt Lake in Fars Province of Iran

    Science.gov (United States)

    Khayyat Kholghi, Majid; Bastani, Mehrdad; Rakhshandeoroo, Gholamreza

    2010-05-01

    One of the most salty lakes in Iran is located in North-East of Fars province with Electrical Conductivities (EC) of up to 61420 μmhos/cm where water supply depends severely on groundwater resources. Increasing demand for freshwater and overexploitation of the aquifer has caused a drawdown in groundwater levels followed by a seawater intrusion into the coastal aquifer in the vicinity of salt lake. Because of invalid appropriate groundwater flow and solute transport parameter values of the coastal system, studying and modelling of saltwater intrusion in this region is in some way complicated. These unknown parameters are consisted of hydraulic conductivity, porosity, specific storage coefficient and longitudinal dispersivity. In this research, it is tried to facilitate study this problem by means of SEAWAT code, which is suitable for variable-density groundwater flow modelling. In the process of calibrating the simulation and estimating the required unknown parameters, an attempt at inverse modelling of a seawater intrusion system is made by using genetic algorithm method as the optimization procedure. The auto-calibration objective function is defined with the root mean square errors (RMSE) between the observed and the simulated values. The observed data are consisted of both hydraulic heads and concentrations obtained from observation wells. Firstly, the SEAWAT code has been used for forward solution part of salt water intrusion phenomena and then a program is written in MATLAB for coupling the forward and inverse processes. In the developed code, the flow and transport parameters are estimated simultaneously in steady and transient states. Using these estimated parameters in the structure of the simulation consequences more accurate results and more trustable model for next applications in management of the coastal aquifer. Key words seawater intrusion; saline groundwater resources; SEAWAT; genetic algorithm; Fars province

  19. Weather and eared grebe winter migration near the Great Salt Lake, Utah.

    Science.gov (United States)

    Williams, Augusta A; Laird, Neil F

    2017-10-18

    This study provides insight from the use of weather radar observations to understand the characteristics of the eared grebe migration near the Great Salt Lake (GSL) and provides unique information on weather conditions connected to these migration events. Doppler weather radar measurements from the Salt Lake City, Utah WSR-88D radar site (KMTX), along with meteorological surface and rawinsonde data, were used to identify and examine 281 eared grebe migration events across 15 winters from 1997/1998 through 2011/2012. An average of about 19 migration events occurred each winter with considerable interannual variability, as well as large variance in the spatial area and number of birds departing the GSL during each event. The migration events typically occurred during clear sky conditions in the presence of surface high pressure and colder than average surface temperatures. Migration events began 55 min after sunset, on average across the winter seasons, and in one case we demonstrate that an extended, nonstop flight was initiated of the departing eared grebes to northern Mexico. Eared grebes leaving the GSL largely flew above the freezing level with a mean northerly tailwind at flight altitude of 3.1 m s -1 and a westerly, cross-flight wind of 5.0 m s -1 while having an average flight speed at cruising altitude of 16.9 m s -1 , or 61 km h -1 . In addition to determining the variability of meteorological conditions during migration events across the 15 winters, atmospheric conditions during the largest migration event observed are presented and discussed.

  20. Weather and eared grebe winter migration near the Great Salt Lake, Utah

    Science.gov (United States)

    Williams, Augusta A.; Laird, Neil F.

    2017-10-01

    This study provides insight from the use of weather radar observations to understand the characteristics of the eared grebe migration near the Great Salt Lake (GSL) and provides unique information on weather conditions connected to these migration events. Doppler weather radar measurements from the Salt Lake City, Utah WSR-88D radar site (KMTX), along with meteorological surface and rawinsonde data, were used to identify and examine 281 eared grebe migration events across 15 winters from 1997/1998 through 2011/2012. An average of about 19 migration events occurred each winter with considerable interannual variability, as well as large variance in the spatial area and number of birds departing the GSL during each event. The migration events typically occurred during clear sky conditions in the presence of surface high pressure and colder than average surface temperatures. Migration events began 55 min after sunset, on average across the winter seasons, and in one case we demonstrate that an extended, nonstop flight was initiated of the departing eared grebes to northern Mexico. Eared grebes leaving the GSL largely flew above the freezing level with a mean northerly tailwind at flight altitude of 3.1 m s-1 and a westerly, cross-flight wind of 5.0 m s-1 while having an average flight speed at cruising altitude of 16.9 m s-1, or 61 km h-1. In addition to determining the variability of meteorological conditions during migration events across the 15 winters, atmospheric conditions during the largest migration event observed are presented and discussed.

  1. Reconnaissance of the shallow-unconfined aquifer in Salt Lake Valley, Utah

    Science.gov (United States)

    Seiler, R.L.; Waddell, K.M.

    1984-01-01

    The shallow-unconfined aquifer in Salt Lake (Jordan) Valley, Utah, seldom is used for domestic or industrial purposes because it yields water slowly and is readily contaminated. The water in the aquifer, however, can flood basements and is a potential source of contamination to other water supplies. In about one-half of the valley, water in the shallow-unconfined aquifer is less than 10 feet below land surface. The general direction of flow in the shallow aquifer is toward the Jordan River. Water levels in the north part of the valley and along the Jordan River are highest in March or April and in the south part of the valley are highest in late summer. The smallest concentrations of dissolved solids in water from wells along the east side of the valley, and the greatest concentrations are in the northwest part of the valley near the Great Salt Lake. Large dissolved-solids concentrations are found near some landfills and tailings areas. Nitrate-nitrogen concentrations ranged from less than 0.1 to 86 milligrams per liter and nitrate-nitrogen concentrations from less than 0.02 to 0.85 milligram per liter. Some of the largest nitrate-nitrogen concentrations were found in water wells near animal pens. The greatest concentrations of trace elements generally came from wells near landfills and tailings area. The greatest measured concentration of cadmium was 200 microgram per liter, of mercury 0.1 microgram per liter, of lead 46 micrograms per liter, of iron 37,000 micrograms per liter and of arsenic 360 micrograms per liter. Synthetic organic chemicals were found in water from several wells. The greatest measured concentration of benzene was 400 micrograms per liter, of phenol 660 micrograms per liter, of 1,1 dichloroethane 20 micrograms per liter, of tichloroethylene 8 micrograms per liter , and of chloroethylene, 11 micrograms per liter. The greatest concentrations were in water from wells near landfills. (USGS)

  2. Reconstructing historical changes in the environmental health of watersheds by using sediment cores from lakes and reservoirs in Salt Lake Valley, Utah

    Science.gov (United States)

    Naftz, David L.; Stephens, Doyle W.; Callender, Edward; Van Metre, Peter C.

    2000-01-01

    The Great Salt Lake Basins study area of the National Water-Quality Assessment (NAWQA) program, which began in 1997, is increasing the scientific understanding of factors that affect surface-water quality within the study-area boundaries (fig. 1). One way to improve the understanding of these factors is to look at historical trends in existing water-quality data. Unfortunately, short record lengths, in- consistent analytical methods, numerous measurements at less than detection levels, and questionable accuracy limit the usefulness of historical monitoring data for most trace inorganic and organic contaminants found in streams, rivers, and lakes in the study area.

  3. Paleogeographic significance of the Cardium, Potamids and Foraminifera living in intra-continental salt lakes of North Africa (Sahara Quaternary, Egypt Present lakes)

    Science.gov (United States)

    Plaziat, J.-C.

    The widespread Cardium ( Cerastoderma) fauna of Quaternary lakes of the Sahara gave rise to the "Saharian seas" hypothesis. Present Egyptian (Fayum, Siwa) and Algerian Holocene salt lakes show an evolution from a fresh water fauna to a Cardium, Potamids and Foraminifera fauna in spite of their considerable distance from the Mediterranean sea and their altitude above sea level. The inevitable conclusion is that thalassoid or so-called margino-littoral faunas cannot be used as indicative of sea connection, or even proximity, in ancient deposits.

  4. Estimating selenium removal by sedimentation from the Great Salt Lake, Utah

    Science.gov (United States)

    Oliver, W.; Fuller, C.; Naftz, D.L.; Johnson, W.P.; Diaz, X.

    2009-01-01

    The mass of Se deposited annually to sediment in the Great Salt Lake (GSL) was estimated to determine the significance of sedimentation as a permanent Se removal mechanism. Lake sediment cores were used to qualitatively delineate sedimentation regions (very high to very low), estimate mass accumulation rates (MARs) and determine sediment Se concentrations. Sedimentation regions were defined by comparison of isopach contours of Holocene sediment thicknesses to linear sedimentation rates determined via analysis of 210Pb, 226Ra, 7Be and 137Cs activity in 20 short cores (10 cm). These MARs in the upper 1-2 cm of each long core ranged from 0.019 to 0.105 gsed/cm2/a. Surface sediment Se concentrations in the upper 1 or 2 cm of each long core ranged from 0.79 to 2.47 mg/kg. Representative MARs and Se concentrations were used to develop mean annual Se removal by sedimentation in the corresponding sedimentation region. The spatially integrated Se sedimentation rate was estimated to be 624 kg/a within a range of uncertainty between 285 and 960 kg/a. Comparison to annual Se loading and other potential removal processes suggests burial by sedimentation is not the primary removal process for Se from the GSL. ?? 2009 Elsevier Ltd.

  5. Comparison of Radiocarbon Ages for Multiproxy Paleoclimate Reconstruction of the Great Salt Lake, Utah

    Science.gov (United States)

    Nielson, K. E.; Bowen, G. J.; Eglinton, T. I.

    2008-12-01

    Multiproxy paleoclimate reconstructions from high sedimentation-rate systems offer promising opportunities to deconvolve multiple aspects climate system response to past forcing. However, the time-equivalence of proxies must be established before such reconstructions can be usefully interpreted. Differences in source ages, transport pathways, and surface residence times for substrates may lead to differences in lag times between proxy formation and deposition, compromising comparative analysis of data from multiple proxies. We used multi-substrate radiocarbon dating to investigate the potential for multi-proxy reconstruction of Holocene changes in the volume of the Great Salt Lake (GSL), Utah, based on the stable isotope composition of organic and inorganic substrates in lake sediment cores. Among potential substrates for this work are normal alkanes of vascular higher plant and algal origin, fossil cysts of lake-dwelling brine shrimp (Artemia), and micritic aragonite. Radiocarbon ages for all organic substrates (alkanes, cysts) sampled at any given core depth are concordant within analytical uncertainty and are similar to ages determined on land-plant debris and filamentous algae isolated from the sediment. Inorganic carbonate, in contrast, is depleted in 14C compare to the organic proxies, giving ages that were apparently 2000 to 3000 years older, likely due to winnowing and re-deposition of carbonate at the core site. These results suggest that the maximum temporal resolution achievable through analysis of mineral substrates is on the order of several millennia. Although the limited precision of the radiocarbon analysis precludes precise determination of the maximum potential resolution of organic-proxy based climate reconstructions, the relatively high sedimentation rates (50--150 cm/kyr) and age-equivalence of the substrates analyzed implies that sub- centennial scale resolution should be achievable throughout much of the Holocene portion of the GSL

  6. Potential for Waterborne and Invertebrate Transmission of West Nile Virus in the Great Salt Lake, Utah.

    Science.gov (United States)

    Lund, Melissa; Shearn-Bochsler, Valerie; Dusek, Robert J; Shivers, Jan; Hofmeister, Erik

    2017-07-15

    In November and December of 2013, a large mortality event involving 15,000 to 20,000 eared grebes ( Podiceps nigricollis ) occurred at the Great Salt Lake (GSL), UT. The onset of the outbreak in grebes was followed by a mortality event in >86 bald eagles ( Haliaeetus leucocephalus ). During the die-off, West Nile virus (WNV) was detected by reverse transcription-PCR (RT-PCR) or viral culture in the carcasses of grebes and eagles submitted to the National Wildlife Health Center. However, no activity of mosquitoes, the primary vectors of WNV, was detected by the State of Utah's WNV monitoring program. The transmission of WNV has rarely been reported during the winter in North America in the absence of known mosquito activity; however, the size of this die-off, the habitat in which it occurred, and the species involved are unique. We experimentally investigated whether WNV could survive in water with a high salt content, as found at the GSL, and whether brine shrimp, the primary food of migrating eared grebes on the GSL, could have played a role in the transmission of WNV to feeding birds. We found that WNV can survive up to 72 h at 4°C in water containing 30 to 150 ppt NaCl, and brine shrimp incubated with WNV in 30 ppt NaCl may adsorb WNV to their cuticle and, through feeding, infect epithelial cells of their gut. Both mechanisms may have potentiated the WNV die-off in migrating eared grebes on the GSL. IMPORTANCE Following a major West Nile virus die-off of eared grebes and bald eagles at the Great Salt Lake (GSL), UT, in November to December 2013, this study assessed the survival of West Nile virus (WNV) in water as saline as that of the GSL and whether brine shrimp, the major food for migrating grebes, could have played a role as a vector for the virus. While mosquitoes are the major vector of WNV, under certain circumstances, transmission may occur through contaminated water and invertebrates as food. Copyright © 2017 American Society for Microbiology.

  7. Modelling water and salt balances in a deep, groundwater-throughflow lake-Lake Purrumbete, southeastern Australia

    National Research Council Canada - National Science Library

    Yihdego, Yohannes; Webb, John; Leahy, Paul

    2016-01-01

    .... A modified difference water budget method for lakes, that estimates net groundwater flux through the difference between the level of the lake and the water table, along with the specific yield...

  8. Development of a Site-specific Standard for Selenium in Open Waters of Great Salt Lake, Utah

    Science.gov (United States)

    Moellmer, W. O.; Miller, T.; Ohlendorf, H.; Denbleyker, J.

    2006-12-01

    The Great Salt Lake (GSL) is a unique terminal lake located adjacent to a rapidly growing metropolitan area in the western United States. The open water of the GSL is protected for its current beneficial uses through the application of a narrative criteria clause in the state water quality standards. The Utah Department of Environmental Quality (DEQ) initiated a process in 2004 to develop a site-specific numeric water quality standard for selenium for the open waters of the GSL to balance protection of the GSL's unique ecology and beneficial uses with burgeoning development. The process the DEQ initiated included the formation of a Great Salt Lake Water Quality Steering Committee and a Science Panel to identify the studies required, manage the studies and finally recommend a site-specific standard. Great Salt Lake Water Quality Steering Committee. The DEQ established the GSL Water Quality Steering Committee (Steering Committee) to provide a forum for stakeholders to assist in guiding the process of developing numeric standards for the lake. This group consists of federal and state regulatory agencies, other public entities, conservation organizations, recreation groups, and industrial users of the lake. Great Salt Lake Science Panel. The DEQ established the GSL Science Panel (Science Panel) to advise the DEQ and Steering Committee and provide overall technical direction and review for the program. The Science Panel is composed of 9 members representing federal and state regulatory agencies, industry and academia. The purpose of the panel is to identify data gaps in the literature, design and oversee scientific investigations to fill critical data gaps, and finally recommend a numeric water quality standard to the Steering Committee. Studies Currently Underway. A partnership of researchers—including local and national experts from education and industry—are collaborating with the DEQ, the Steering Committee, and the Science Panel to complete the studies required

  9. Modeling the Dynamics of the Great Salt Lake as an Integrator of Regional Hydrologic and Climate Processes?

    Science.gov (United States)

    Mohammed, I. N.; Tarboton, D. G.

    2005-12-01

    The Great Salt Lake (GSL), Utah, is the fourth largest, perennial, terminal lake in the world. The Great Salt Lake (GSL) level fluctuates due to the balance between inflows and outflows. These fluctuations are of interest whether they are high (flooding hazards) or low (economic impacts). Inflows are due to streamflow, primarily from the Bear River (54%), Weber River (18%) and Jordan/Provo River (28%) systems. Inflows also include precipitation directly on the lake and groundwater both from the East and West sides. The only outflow is evaporation that is controlled by the climate and area of the lake that changes with level. The GSL reached historic high levels above 1284 m in 1873 and 1986. A historic low at 1278 m occurred in 1963. These fluctuations represent the integrated effect of climate and hydrologic processes as well as the dynamic interaction between lake volume, area and salinity that impact evaporation from the lake. The topographic area-volume relationship in the GSL plays a role in the system dynamics because area is a control on the evaporation outflux. This paper examines the relationships between Basin climate (precipitation and temperature), Inflows to the lake (primarily streamflow) and outflows (evaporation). The role played by the topographic elevation-area-volume relationship on lake dynamics and the correspondence between modes in volume and area distributions and peaks in the area-volume derivative was examined. We derived, using a steady state approximation, the relationship between distributions of lake volume and lake area and the area-volume derivative from the topography/bathymetry. This analysis showed that both the topography/bathymetry and multimodality in the area distribution are required to explain the observed multimodality in the volume distribution. We also separated lake volume changes into increases in the spring (due to spring runoff) and declines in the fall (due to evaporation) and then related these volume changes to

  10. Inputs and internal cycling of nitrogen to a causeway influenced, hypersaline lake, Great Salt Lake, Utah, USA

    Science.gov (United States)

    Naftz, David L.

    2017-01-01

    Nitrogen inputs to Great Salt Lake (GSL), located in the western USA, were quantified relative to the resident nitrogen mass in order to better determine numeric nutrient criteria that may be considered at some point in the future. Total dissolved nitrogen inputs from four surface-water sources entering GSL were modeled during the 5-year study period (2010–2014) and ranged from 1.90 × 106 to 5.56 × 106 kg/year. The railroad causeway breach was a significant conduit for the export of dissolved nitrogen from Gilbert to Gunnison Bay, and in 2011 and 2012, net losses of total nitrogen mass from Gilbert Bay via the Causeway breach were 9.59 × 105 and 1.51 × 106 kg. Atmospheric deposition (wet + dry) was a significant source of nitrogen to Gilbert Bay, exceeding the dissolved nitrogen load contributed via the Farmington Bay causeway surface-water input by >100,000 kg during 2 years of the study. Closure of two railroad causeway culverts in 2012 and 2013 likely initiated a decreasing trend in the volume of the higher density Deep Brine Layer and associated declines in total dissolved nitrogen mass contained in this layer. The large dissolved nitrogen pool in Gilbert Bay relative to the amount of nitrogen contributed by surface-water inflow sources is consistent with the terminal nature of GSL and the predominance of internal nutrient cycling. The opening of the new railroad causeway breach in 2016 will likely facilitate more efficient bidirectional flow between Gilbert and Gunnison Bays, resulting in potentially substantial changes in nutrient pools within GSL.

  11. Imported malaria in Tunisia

    National Research Council Canada - National Science Library

    Bouratbine, A; Chahed, M K; Aoun, K; Krida, G; Ayari, S; Ben Ismail, R

    1998-01-01

    Thanks to the national programme of malaria eradication carried out between 1968 and 1972, there has been no active transmission of the parasitosis in Tunisia since the last indigenous case in 1979...

  12. Large Salt Dust Storms Follow a 30-Year Rainfall Cycle in the Mar Chiquita Lake (Córdoba, Argentina).

    Science.gov (United States)

    Bucher, Enrique H; Stein, Ariel F

    2016-01-01

    Starting in 2006, a new source of intense salt dust storms developed in Mar Chiquita (Córdoba, Argentina), the largest saline lake in South America. Storms originate from vast mudflats left by a 30-year expansion-retreat cycle of the lake due to changes in the regional rainfall regime. The annual frequency of salt dust storms correlated with the size of the salt mudflats. Events were restricted to the coldest months, and reached up to 800 km from the source. Occurrence of dust storms was associated with specific surface colors and textures easily identifiable in satellite images. High-emission surfaces were characterized by the presence of sodium sulfate hydrous/anhydrous crystals (mirabilite and thenardite), and a superficial and variable water table, which may result in the periodic development of a characteristic "fluffy" surface derived from salt precipitation-dissolution processes. HYSPLIT model simulation estimates a deposition maximum near the sources (of about 2.5 kg/ha/yr), and a decreasing trend from the emission area outwards, except for the relative secondary maximum modeled over the mountain ranges in southern Bolivia and northern Argentina due to an orographic effect. The 2009 total deposition of salt dust generated in Mar Chiquita was estimated at 6.5 million tons.

  13. Large Salt Dust Storms Follow a 30-Year Rainfall Cycle in the Mar Chiquita Lake (Córdoba, Argentina.

    Directory of Open Access Journals (Sweden)

    Enrique H Bucher

    Full Text Available Starting in 2006, a new source of intense salt dust storms developed in Mar Chiquita (Córdoba, Argentina, the largest saline lake in South America. Storms originate from vast mudflats left by a 30-year expansion-retreat cycle of the lake due to changes in the regional rainfall regime. The annual frequency of salt dust storms correlated with the size of the salt mudflats. Events were restricted to the coldest months, and reached up to 800 km from the source. Occurrence of dust storms was associated with specific surface colors and textures easily identifiable in satellite images. High-emission surfaces were characterized by the presence of sodium sulfate hydrous/anhydrous crystals (mirabilite and thenardite, and a superficial and variable water table, which may result in the periodic development of a characteristic "fluffy" surface derived from salt precipitation-dissolution processes. HYSPLIT model simulation estimates a deposition maximum near the sources (of about 2.5 kg/ha/yr, and a decreasing trend from the emission area outwards, except for the relative secondary maximum modeled over the mountain ranges in southern Bolivia and northern Argentina due to an orographic effect. The 2009 total deposition of salt dust generated in Mar Chiquita was estimated at 6.5 million tons.

  14. Aerosol Particles from Dried Salt-Lakes and Saline Soils Carried on Dust Storms over Beijing

    Directory of Open Access Journals (Sweden)

    Xingying Zhang

    2009-01-01

    Full Text Available Characteristics of individual particles from a super dust storm (DS on 20 March 2002, and those of non dust storm aero sols for Beijing (NDS and Duolun (DL (a desert area are determined using a variety of methods. In China, typically the source of aero sols in dust storms is thought to be deserts with alumino silicates being the main constituent particles; how ever, this does not reflect a complete analysis with our evidence indicating potential alternate dust sources along the storm's trans port path. Individual particle anal y sis of aero sols collected from a super dust storm on 20 March 2002 in Beijing shows that among all the 14 elements measured, only S and Cl have re mark able positive correlation. 82.5% of all particles measured contained both S and Cl, and the relative mass per cent age of S and Cl in these particles is much higher than the average of all particles. 62.0% of all particles contained S, Cl, and Na, in which the concentration of Na is 1.4 times higher than average. PMF (Positive Matrix Factorization anal y sis indicates that NaCl and Na2SO4 are major components of these particles with S and Cl showing significant positive correlation. More over, SO4 2- and Cl- also show significant positive correlation in bulk aero sol analysis. XPS (X-ray Pho to electron Spectros copy analysis of the surface of aero sols demonstrates that concentrations of Na and S on particles from the dust storm are higher than those from non-dust storm particles in Beijing and also for particles from. It is very likely that particles enriched with S, Cl, and Na is from the surface soils of dried salt-lakes and saline soils enriched with chloride and sulfate. This evidence demonstrates that be sides deserts, surface soils from dry salt-lakes and saline soils of arid and semi-arid areas are also sources of particulates in dust storms over Beijing.

  15. Energy Savings Calculations for Heat Island Reduction Strategies in Baton Rouge, Sacramento and Salt Lake City

    Energy Technology Data Exchange (ETDEWEB)

    Konopacki, S.; Akbari, H.

    2000-03-01

    In 1997, the US Environmental Protection Agency (EPA) established the ''Heat Island Reduction Initiative'', to quantify the potential benefits of Heat Island Reduction (HIR) strategies (i.e., shade trees, reflective roofs, reflective pavements and urban vegetation) to reduce cooling energy use in buildings, lower the ambient air temperature and improve urban air quality in cities, and reduce CO2 emissions from power plants. Under this initiative, the Urban Heat Island Pilot Project (UHIPP) was created with the objective to investigate the potential of HIR strategies in residential and commercial buildings in three initial UHIPP cities: Baton Rouge, Sacramento and Salt Lake City. This paper summarizes our efforts to calculate the annual energy savings, peak power avoidance and annual C02 reduction of HIR strategies in the three initial cities. In this analysis, we focused on three building types that offer most savings potential: single-family residence, office and retail store. Each building type was characterized in detail by old or new construction and with a gas furnace or an electric heat pump. We defined prototypical building characteristics for each building type and simulated the impact of HIR strategies on building cooling and heating energy use and peak power demand using the DOE-2.IE model. Our simulations included the impact of (1) strategically-placed shade trees near buildings [direct effect], (2) use of high-albedo roofing material on building [direct effect], (3) combined strategies I and 2 [direct effect], (4) urban reforestation with high-albedo pavements and building surfaces [indirect effect] and (5) combined strategies 1, 2 and 4 [direct and indirect effects]. We then estimated the total roof area of air-conditioned buildings in each city using readily obtainable data to calculate the metropolitan-wide impact of HIR strategies. The results show, that in Baton Rouge, potential annual energy savings of $15M could be realized by

  16. Water in the Oceanic Lithosphere: Salt Lake Crater Xenoliths, Oahu, Hawaii

    Science.gov (United States)

    Peslier, Anne H.; Bizimis, Michael

    2010-01-01

    Water can be present in nominally anhydrous minerals of peridotites in the form of hydrogen bonded to structural oxygen. Such water in the oceanic upper mantle could have a significant effect on its physical and chemical properties. However, the water content of the MORB source has been inferred indirectly from the compositions of basalts. Direct determinations on abyssal peridotites are scarce because they have been heavily hydrothermally altered. Here we present the first water analyses of minerals from spinel peridotite xenoliths of Salt Lake Crater, Oahu, Hawaii, which are exceptionally fresh. These peridotites are thought to represent fragments of the Pacific oceanic lithosphere that was refertilized by alkalic Hawaiian melts. A few have unradiogenic Os and radiogenic Hf isotopes and may be fragments of an ancient (2 Ga) depleted and recycled lithosphere. Water contents in olivine (Ol), orthopyroxene (Opx), and clinopyroxene (Cpx) were determined by FTIR spectrometry. Preliminary H_{2}O contents show ranges of 8-10 ppm for Ol, 151-277 ppm for Opx, and 337-603 ppm for Cpx. Reconstructed bulk rock H_{2}O contents range from 88-131 ppm overlapping estimates for the MORB source. Water contents between Ol minerals of the same xenolith are heterogeneous and individual OH infrared bands vary within a mineral with lower 3230 cm^{-1} and higher 3650-3400 cm^{-1} band heights from core to edge. This observation suggests disturbance of the hydrogen in Ol likely occurring during xenolith entrainment to the surface. Pyroxene water contents are higher than most water contents in pyroxenes from continental peridotite xenoliths and higher than those of abyssal peridotites. Cpx water contents decrease with increasing degree of depletion (e.g. increasing Fo in Ol and Cr# in spinel) consistent with an incompatible behavior of water. However Cpx water contents also show a positive correlation with LREE/HREE ratios and LREE concentrations consistent with refertilization. Opx water

  17. Metagenomic cloning and characterization of Na⁺ transporters from Huamachi Salt Lake in China.

    Science.gov (United States)

    Gao, Miao; Tao, Li; Chen, Sanfeng

    2013-02-22

    Moderately halophilic bacteria are a kind of extreme environment microorganism that can tolerate moderate salt concentrations ranging from 0.5M to 2.5M. Here, via a metagenomic library screen, we identified four putative Na(+) transporters, designated H7-Nha, H16-Mppe, H19-Cap and H35-Mrp, from moderately halophilic community in the hypersaline soil of Huamachi Salt Lake, China. Functional complementation observed in a Na(+)(Ca(2+))/H(+) antiporter-defective Escherichia coli mutant (KNabc) suggests that the four putative Na(+) transporters could confer cells a capacity of Na(+) resistance probably by enhancing Na(+) or Ca(2+) efflux, but not Li(+) or K(+) exchange. Blastp analysis of the deduced amino-acid sequences indicates that H7-Nha has 71% identity to the NhaG Na(+)/H(+) antiporter of Bacillus subtilis, while H19-Cap shows 99% identity to Enterobacter cloacae Ca(2+) antiporter. Interestingly, H16-Mppe shares 59% identity to the metallophosphoesterase of Bacillus cellulosilyticus and H35-Mrp shows 68% identity to multidrug resistance protein of Lysinibacillus sphaericus. This is the first report that predicts a potential role of metallophosphoesterase in Na(+) resistance in halophilic bacteria. Furthermore, everted membrane vesicles prepared from E. coli cells harboring H7-Nha exhibit Na(+)/H(+) antiporter activity, but not Li(+) (K(+))/H(+) antiporter activity, confirming that H7-Nha supports Na(+) resistance mainly via Na(+)/H(+) antiport. Our report also demonstrates that metagenomic library screen is a convenient and effective way to explore more novel types of Na(+) transporters. Copyright © 2012 Elsevier GmbH. All rights reserved.

  18. Decadal-to-centennial-scale climate variability: Insights into the rise and fall of the Great Salt Lake

    Science.gov (United States)

    Mann, Michael E.; Lall, Upmanu; Saltzman, Barry

    1995-01-01

    We demonstrate connections between decadal and secular global climatic variations, and historical variations in the volume of the Great Salt Lake. The decadal variations correspond to a low-frequency shifting of storm tracks which influence winter precipitation and explain nearly 18% of the interannual and longer-term variance in the record of monthly volume change. The secular trend accounts for a more modest approximately 1.5% of the variance.

  19. Energy Budgets of Eared Grebes on the Great Salt Lake and Implications for Harvest of Brine Shrimp

    OpenAIRE

    Conover, Michael R.; Caudell, Joe N.

    2009-01-01

    About 1.5-million eared grebes (Podiceps nigricollis), representing half of the North American population, stage on Utah's Great Salt Lake, USA (GSL) during autumn migration to forage on brine shrimp (Artemia franciscana). Indirectly competing with birds for brine shrimp are commercial harvesters who annually collect >1 million kg (dry wt) of shrimp cysts (i.e., hardened eggs), an amount that during some years equals up to half of all brine shrimp cysts produced annually on the GSL. No inform...

  20. Simulations of a Cold-Air Pool in Utah's Salt Lake Valley: Sensitivity to Land Use and Snow Cover

    Science.gov (United States)

    Foster, Christopher S.; Crosman, Erik T.; Horel, John D.

    2017-02-01

    Obtaining realistic land-surface states for initial and boundary conditions is important for the numerical weather prediction of many atmospheric phenomena. Here we investigate model sensitivity to land use and snow cover for a persistent wintertime cold-air pool in northern Utah during 1-8 January 2011. A Weather Research and Forecast model simulation using the 1993 United States Geological Survey land-use and North American Mesoscale model reanalysis snow-cover datasets is compared to an improved configuration using the modified 2011 National Land Cover Database and a more realistic representation of snow cover. The improved surface specification results in an increase (decrease) in urban land cover (Great Salt Lake surface area), and changes to the snow-cover initialization, depth, extent, and albedo. The results obtained from the model simulations are compared to observations collected during the Persistent Cold-Air Pool Study. The changes in land use and snow cover and the resulting impacts on the surface albedo and surface heat fluxes contributed to near-surface air temperature increases of 1-2°C in urban areas and decreases of 2-4°C in areas surrounding the Great Salt Lake. Although wind speeds in the boundary layer were overestimated in both simulations, shallow thermally-driven and terrain-forced flows were generally lessened in intensity and breadth in response to the decreased areal extent of the Great Salt Lake and increases in the urban footprint.

  1. Trend Analysis of Soil Salinity in Different Land Cover Types Using Landsat Time Series Data (case Study Bakhtegan Salt Lake)

    Science.gov (United States)

    Taghadosi, M. M.; Hasanlou, M.

    2017-09-01

    Soil salinity is one of the main causes of desertification and land degradation which has negative impacts on soil fertility and crop productivity. Monitoring salt affected areas and assessing land cover changes, which caused by salinization, can be an effective approach to rehabilitate saline soils and prevent further salinization of agricultural fields. Using potential of satellite imagery taken over time along with remote sensing techniques, makes it possible to determine salinity changes at regional scales. This study deals with monitoring salinity changes and trend of the expansion in different land cover types of Bakhtegan Salt Lake district during the last two decades using multi-temporal Landsat images. For this purpose, per-pixel trend analysis of soil salinity during years 2000 to 2016 was performed and slope index maps of the best salinity indicators were generated for each pixel in the scene. The results of this study revealed that vegetation indices (GDVI and EVI) and also salinity indices (SI-1 and SI-3) have great potential to assess soil salinity trends in vegetation and bare soil lands respectively due to more sensitivity to salt features over years of study. In addition, images of May had the best performance to highlight changes in pixels among different months of the year. A comparative analysis of different slope index maps shows that more than 76% of vegetated areas have experienced negative trends during 17 years, of which about 34% are moderately and highly saline. This percent is increased to 92% for bare soil lands and 29% of salt affected soils had severe salinization. It can be concluded that the areas, which are close to the lake, are more affected by salinity and salts from the lake were brought into the soil which will lead to loss of soil productivity ultimately.

  2. Formation of aragonite cement by nannobacteria in the Great Salt Lake, Utah

    Science.gov (United States)

    Pedone, Vicki A.; Folk, Robert L.

    1996-08-01

    Brine-shrimp egg cases in growth cavities in modern stromatolites in the Great Salt Lake, Utah, are replaced by aragonite and cemented together by aragonite cement. The fabric of the cement changes dramatically as the distance from the egg case increases. The cement within 50 to 70 μm of the egg case exhibits a random fabric of 10 to 20 μm equant crystals. The surface of the cement is covered by bead-like bumps, 0.1 μm in diameter, interpreted as nannobacteria. Overlying the random, “beaded” fabric with a relatively abrupt transition are epitaxial, prismatic aragonite crystals that have smooth crystal surfaces lacking bead-like bodies. The smooth-surfaced prismatic aragonite crystals are interpreted to be “normal” abiotic precipitates, whereas the “beaded” microspar is interpreted to result from biotic processes, where the nannobacteria serve as catalysts for creation of the cement. A population explosion of bacteria occurs as the organic material of egg case rots, which alters the microchemical environment and induces a rapid precipitation of aragonite, enclosing tens of thousands of nannobacteria. As the organic material is destroyed, reproduction of bacteria slows and epitaxial, prismatic aragonite crystals nucleate and grow abiotically on the structureless, “biotic” layer.

  3. Halorientalis brevis sp. nov., Isolated from an Inland Salt Lake of China.

    Science.gov (United States)

    Yuan, Pan-Pan; Yin, Shuai; Han, Dong; Zhang, Wen-Jiao; Cui, Heng-Lin

    2015-09-01

    Halophilic archaeal strain YC89(T) was isolated from Yuncheng salt lake in Shanxi, China. Cells from strain YC89(T) were short rods, lysed in distilled water, stained Gram-negative and formed red-pigmented colonies on agar plate. Strain YC89(T) was able to grow at 25-50°C (optimum 37°C), at 1.4-4.8 M NaCl (optimum 2.6-3.1 M), at 0-1.0 M MgCl2 (optimum 0.3 M) and at pH 6.0-9.5 (optimum pH 7.5). The major polar lipids are phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, sulfated mannosyl glucosyl diether and two unknown glycolipids. 16S rRNA gene analysis revealed that strain YC89(T) was phylogenetically related to Halorientalis persicus D108(T) (95.6% nucleotide identity) and H. regularis TNN28(T) (95.3% nucleotide identity). The rpoB' gene similarities between strain YC89(T) and H. persicus IBRC-M 10043(T) and H. regularis TNN28(T) were 88.1 and 88.0%, respectively. The DNA G+C content of strain YC89(T) was determined to be 61.3 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain YC89(T) (=CGMCC 1.12125(T) = JCM 18366(T)) represents a new species of Halorientalis, for which the name H. brevis sp. nov. is proposed.

  4. Brevibacterium salitolerans sp. nov., an actinobacterium isolated from salt-lake sediment.

    Science.gov (United States)

    Guan, Tong-Wei; Zhao, Ke; Xiao, Jing; Liu, Ying; Xia, Zhan-Feng; Zhang, Xiao-Ping; Zhang, Li-Li

    2010-12-01

    A novel bacterium, designated TRM 415(T), belonging to the genus Brevibacterium, was isolated from a sediment sample from a salt lake in Xinjiang province, China. Comparative 16S rRNA gene sequence analysis indicated that strain TRM 415(T) was phylogenetically most closely related to Brevibacterium album YIM 90718(T) (98.4 % sequence similarity) and had low similarity (Brevibacterium; however, DNA-DNA hybridization studies between strain TRM 415(T) and B. album YIM 90718(T) showed only 41.3 % relatedness. Strain TRM 415(T) possessed meso-diaminopimelic acid as the diagnostic cell-wall diamino acid, MK-8(H(2)) as the major menaquinone and polar lipids including phosphatidylglycerol and diphosphatidylglycerol. The major fatty acids were anteiso-C(17 : 0) and anteiso-C(15 : 0). The genomic DNA G+C content was 69 mol%. Based on the evidence from this polyphasic study, strain TRM 415(T) represents a novel species of the genus Brevibacterium, for which the name Brevibacterium salitolerans sp. nov. is proposed. The type strain is TRM 415(T) (=JCM 15900(T) =CCTCC AB 208328(T) =KCTC 19616(T)).

  5. The Educational System of Tunisia.

    Science.gov (United States)

    Office of Education (DHEW), Washington, DC.

    An overview of the basic system of education in Tunisia is presented in this booklet. Since Tunisia's independence in 1956, the government has emphasized the role of education as a major factor in building a modern nation. The educational system in Tunisia is based on both the nation's own rich cultural background and also on the linguistic and…

  6. Calculating salt loads to Great Salt Lake and the associated uncertainties for water year 2013; updating a 48 year old standard

    Science.gov (United States)

    Shope, Christopher L.; Angeroth, Cory E.

    2015-01-01

    Effective management of surface waters requires a robust understanding of spatiotemporal constituent loadings from upstream sources and the uncertainty associated with these estimates. We compared the total dissolved solids loading into the Great Salt Lake (GSL) for water year 2013 with estimates of previously sampled periods in the early 1960s.We also provide updated results on GSL loading, quantitatively bounded by sampling uncertainties, which are useful for current and future management efforts. Our statistical loading results were more accurate than those from simple regression models. Our results indicate that TDS loading to the GSL in water year 2013 was 14.6 million metric tons with uncertainty ranging from 2.8 to 46.3 million metric tons, which varies greatly from previous regression estimates for water year 1964 of 2.7 million metric tons. Results also indicate that locations with increased sampling frequency are correlated with decreasing confidence intervals. Because time is incorporated into the LOADEST models, discrepancies are largely expected to be a function of temporally lagged salt storage delivery to the GSL associated with terrestrial and in-stream processes. By incorporating temporally variable estimates and statistically derived uncertainty of these estimates,we have provided quantifiable variability in the annual estimates of dissolved solids loading into the GSL. Further, our results support the need for increased monitoring of dissolved solids loading into saline lakes like the GSL by demonstrating the uncertainty associated with different levels of sampling frequency.

  7. Astrobiological significance of the sabkha life and environments of southern Tunisia

    Science.gov (United States)

    Stivaletta, Nunzia; Barbieri, Roberto; Picard, Christine; Bosco, Marco

    2009-05-01

    In high-salinity and water-scarce environments, such as in hot and dry deserts, species develop adaptive strategies that are necessary for living in such harsh conditions. Continental ephemeral salt lakes (sabkhas) with periodic flooding from subsurface groundwater followed by high salt concentrations, such as the ones of the northern Africa Chotts, rank among the geological settings wherein the combined effect of salt concentration and fluctuation of water availability make the environment unstable and can thereafter lead to extreme changes. The present study investigates the continental sabkha environments of southern Tunisia, in which ecological niches (i.e. water and salt precipitates, including halite, gypsum, and dolomite) host microbial life. Halophilic microorganisms can be trapped in the extensive saline crusts of halite and gypsum, which can be regarded as the first step of their delivery to the fossil record. The study of halophiles can provide clues for the understanding of life strategies in extreme terrestrial environments, such as sabkhas, which are potential good terrestrial analogs for evaporite-bearing Martian deposits.

  8. Late quaternary geomorphology of the Great Salt Lake region, Utah, and other hydrographically closed basins in the western United States: A summary of observations

    Science.gov (United States)

    Currey, Donald R.

    1989-01-01

    Attributes of Quaternary lakes and lake basins which are often important in the environmental prehistory of semideserts are discussed. Basin-floor and basin-closure morphometry have set limits on paleolake sizes; lake morphometry and basin drainage patterns have influenced lacustrine processes; and water and sediment loads have influenced basin neotectonics. Information regarding inundated, runoff-producing, and extra-basin spatial domains is acquired directly from the paleolake record, including the littoral morphostratigraphic record, and indirectly by reconstruction. Increasingly detailed hypotheses regarding Lake Bonneville, the largest late Pleistocene paleolake in the Great Basin, are subjects for further testing and refinement. Oscillating transgression of Lake Bonneville began about 28,000 yr B.P.; the highest stage occurred about 15,000 yr B.P., and termination occurred abruptly about 13,000 yr B.P. A final resurgence of perennial lakes probably occurred in many subbasins of the Great Basin between 11,000 and 10,000 yr B.P., when the highest stage of Great Salt Lake (successor to Lake Bonneville) developed the Gilbert shoreline. The highest post-Gilbert stage of Great Salt Lake, which has been one of the few permanent lakes in the Great Basin during Holocene time, probably occurred between 3,000 and 2,000 yr B.P.

  9. Halopenitus persicus gen. nov., sp. nov., an archaeon from an inland salt lake.

    Science.gov (United States)

    Amoozegar, Mohammad Ali; Makhdoumi-Kakhki, Ali; Shahzadeh Fazeli, Seyed Abolhassan; Azarbaijani, Reza; Ventosa, Antonio

    2012-08-01

    A novel pale pink-pigmented halophilic archaeon, strain DC30(T), was isolated from Aran-Bidgol salt lake, a hypersaline playa in Iran. Cells of strain DC30(T) were non-motile and pleomorphic, from rods to triangular or disc-shaped. Strain DC30(T) required at least 1.7 M NaCl and 0.05 M MgCl(2) for growth (optimum, 3 M NaCl and 0.1 M MgCl(2)). The optimum pH and temperature for growth of strain DC30(T) were pH 7.5 and 40 °C, respectively, although it was capable of growth over pH and temperature ranges of 6.5-8.5 and 25-50 °C, respectively. Analysis of the 16S rRNA gene sequence showed that strain DC30(T) was a member of the family Halobacteriaceae. However, it had low 16S rRNA gene sequence similarities of 92.4%, 89.4% and 89.1% to the most closely related haloarchaeal taxa, the type species of the genera Halorubrum, Halogranum and Haloplanus, respectively. The DNA G+C content was 66.0 mol%. Phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester, common phospholipids found in haloarchaea, were present. Three minor phospholipids and one unidentified glycolipid were also observed. The only quinone present was MK-8(II-H(2)). The physiological, biochemical and phylogenetic differences between strain DC30(T) and other previously described genera of extremely halophilic archaea suggest that strain DC30(T) represents a novel species in a new genus within the family Halobacteriaceae, for which the name Halopenitus persicus gen. nov., sp. nov. is proposed. The type strain of Halopenitus persicus is DC30(T) ( = IBRC 10041(T) = KCTC 4046(T)).

  10. Halobellus rarus sp. nov., a halophilic archaeon from an inland salt lake of China.

    Science.gov (United States)

    Zhang, Wen-Jiao; Han, Dong; Qiu, Xing-Xing; Zhao, Mei-Lin; Mou, Yun-Zhuang; Cui, Heng-Lin; Li, Zheng-Rong

    2013-09-01

    Two halophilic archaeal strains, YC21(T) and YC77, were isolated from an inland salt lake of China. Both have pleomorphic rod-shaped cells that lyse in distilled water, stain Gram-negative and form red-pigmented colonies. They are neutrophilic, require at least 2.1 M NaCl for growth under the optimum growth temperature of 37 °C. The major polar lipids of the two strains were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS), two major glycolipids (GL1 and GL2) chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1) and mannosyl glucosyl diether (DGD-1), respectively. Trace amounts of two unidentified lipids (GL0-1 and GL0-2) were also detected. The 16S rRNA gene sequences of the two strains are 99.9 % identical, show 94.0-98.9 % similarity to the closest relative members of Halobellus of the family Halobacteriaceae. The rpoB' gene similarity between strains YC21(T) and YC77 is 99.8 % and show 90.3-95.3 % similarity to the closest relative members of Halobellus. The DNA G+C content of strains YC21(T) and YC77 were 66.1 and 66.2 mol%, respectively. The DNA-DNA hybridization value between strain YC20(T) and strain YC77 was 89 %, and the two strains showed low DNA-DNA relatedness with Halobellus limi TBN53(T), the most related member of Halobellus. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains YC21(T) and YC77 represent a novel species of the genus Halobellus, for which the name Halobellus rarus sp. nov. is proposed. The type strain is YC21(T) (=CGMCC 1.12121(T) = JCM 18362(T)).

  11. A SURVEY OF LANDNET SITES FOCUSING ON TUZ GÖLÜ SALT LAKE, TURKEY

    Directory of Open Access Journals (Sweden)

    S. Z. Gürbüz

    2012-07-01

    Full Text Available Radiometric calibration is critical to ensure the accuracy, veracity, continuity and reliability of satellite data measured from multiple sensors and platforms, and is thus recognized as a key activity by all satellite operators. For imaging sensors, vicarious methods using natural targets (such as salt lakes, deserts, or flatlands that are well-characterized and preferably temporally and spatially stable as a reference are similarly well established. However, while selecting a target site, it is important that its quality and location are selected to minimize sources of uncertainty for any given sensor. To maximize the benefit from limited resources and minimize the impact on satellite operators, the Infrared Visible Optical Sensor (IVOS sub-group of Committee on Earth Observation Satellites (CEOS Working Group on Calibration and Validation (WGCV has selected a few, well-characterized, regularly instrumented target sites, which have since become known as LANDNET sites. Currently, there are eight LANDNET sites: 1 Dome C, Antarctica; 2 Dunhuang, China, Asia; 3 Lspec Frenchman Flat, NV, USA, North America; 4 Ivanpah, NV/CA, USA, North America; 5 La Crau, France, Europe; 6 Negev, Southern Israel, Asia; 7 Railroad Valley Playa, NV, USA, North America; 8 Tuz Gölü, Central Anatolia, Turkey, Asia. This work summarizes the key characteristics, and areas of application of each of the LANDNET sites, especially that of Tuz Gölü, to guide and inform researchers on site selection, and increase international awareness and collaboration in this field. Additionally, detailed information about the Tuz Gölü, Turkey test site is provided, including geographical characteristics, spatial uniformity qualities, and opportunities for international researchers to conduct experiments and measurements. Practical, technical, and logistical experience gained through the international field campaigns organized over the last few years at Tuz Gölü is also shared in

  12. Halovenus aranensis gen. nov., sp. nov., an extremely halophilic archaeon from Aran-Bidgol salt lake.

    Science.gov (United States)

    Makhdoumi-Kakhki, A; Amoozegar, M A; Ventosa, A

    2012-06-01

    A novel red-pigmented halophilic archaeon, strain EB27(T), was isolated from Aran-Bidgol salt lake, a hypersaline playa in Iran. Cells of strain EB27(T) were non-motile and pleomorphic (rods to triangular or disc-shaped). Strain EB27(T) required at least 2.5 M NaCl and 0.1 M MgCl(2) for growth. Optimal growth was achieved at 4 M NaCl and 0.5 M MgCl(2). The optimum pH and temperature for growth were pH 7.5 and 40 °C; it was able to grow at pH 6.0-8.0 and 25-50 °C. 16S rRNA gene sequence analysis showed that strain EB27(T) is a member of the family Halobacteriaceae; however, levels of 16S rRNA gene sequence similarity were as low as 90.0, 89.3 and 89.1 % to the most closely related haloarchaeal taxa, namely Halalkalicoccus tibetensis DS12(T), Halosimplex carlsbadense 2-9-1(T) and Halorhabdus utahensis AX-2(T), respectively. The DNA G+C content of strain EB27(T) was 61 mol%. Strain EB27(T) contained phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester, common phospholipids found in haloarchaea, together with two minor phospholipids. The only quinone present was MK-8(II-H(2)). Physiological, biochemical and phylogenetic differences between strain EB27(T) and recognized genera of extremely halophilic archaea suggest that this strain represents a novel species in a new genus within the family Halobacteriaceae, for which the name Halovenus aranensis gen. nov., sp. nov. is proposed. The type strain of Halovenus aranensis, the type species of the new genus, is strain EB27(T) ( = IBRC-M 10015(T) = CGMCC 1.11001(T)).

  13. Halopenitus malekzadehii sp. nov., an extremely halophilic archaeon isolated from a salt lake.

    Science.gov (United States)

    Amoozegar, Mohammad Ali; Makhdoumi-Kakhki, Ali; Mehrshad, Maliheh; Fazeli, Seyed Abolhassan Shahzadeh; Ventosa, Antonio

    2013-09-01

    Strain CC65(T), a novel extremely halophilic archaeon, was isolated from a brine sample of a salt lake in Iran. The novel strain was light yellow-pigmented, non-motile, pleomorphic and required at least 1.7 M NaCl and 0.02 M MgCl₂ for growth. Optimal growth was achieved at 3.5 M NaCl and 0.4 M MgCl₂. The optimum pH and temperature for growth were pH 7.5 and 40 °C, respectively, while it was able to grow over a pH and a temperature range of pH 6.5-9.0 and 30-50 °C, respectively. Analysis of 16S rRNA gene sequence revealed that strain CC65(T) clustered with the sole member of the genus Halopenitus, Halopenitus persicus DC30(T) with a sequence similarity of 98.0%. The polar lipid profile of strain CC65(T) consisted of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. An unidentified glycolipid and two minor phospholipids were also observed. The only quinone present was MK-8(II-H₂). The DNA G+C content of strain CC65(T) was 63.8 mol%. On the basis of the biochemical and physiological characteristics, as well as DNA-DNA hybridization (44% with Halopenitus persicus IBRC 10041(T)), strain CC65(T) is classified as a novel species of the genus Halopenitus, for which the name Halopenitus malekzadehii sp. nov. is proposed. The type strain is CC65(T) ( = IBRC-M 10418(T) =KCTC 4045(T)).

  14. Halorussus ruber sp. nov., isolated from an inland salt lake of China.

    Science.gov (United States)

    Xu, Wei-Dong; Zhang, Wen-Jiao; Han, Dong; Cui, Heng-Lin; Yang, Kun

    2015-01-01

    Halophilic archaeal strain YC25(T) was isolated from Yuncheng salt lake in Shanxi, China. Cells of strain YC25(T) were observed to be pleomorphic rods, stained Gram-negative, and formed red-pigmented colonies on solid media. Strain YC25(T) was found to be able to grow at 25-50 °C (optimum 37 °C), at 1.4-4.8 M NaCl (optimum 1.7 M), at 0-1.0 M MgCl2 (optimum 0.01 M), and at pH 5.5-9.0 (optimum pH 6.5). The cells lysed in distilled water, and the minimal NaCl concentration to prevent cell lysis was found to be 8 % (w/v). The major polar lipids of the strain were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS), sulfated galactosyl mannosyl glucosyl diether (S-TGD-1), sulfated mannosyl glucosyl diether (S-DGD-1), galactosyl mannosyl glucosyl diether (TGD-1), mannosyl glucosyl diether (DGD-1), and an unknown diglycosyl diether (DGD-2) chromatographically identical to those of Halorussus rarus CGMCC 1.10122(T). The 16S rRNA gene and rpoB' gene of strain YC25(T) were phylogenetically related to the corresponding genes of Halorussus rarus CGMCC 1.10122(T) (94.3-95.4 and 91.5 % nucleotide identity, respectively). The DNA G+C content of strain YC25(T) was determined to be 63.3 mol%. The phenotypic, chemotaxonomic, and phylogenetic properties suggested that strain YC25(T) (=CGMCC 1.12122(T) = JCM 18363(T)) represents a new species of Halorussus, for which the name Halorussus ruber sp. nov. is proposed.

  15. Islands in the desert: Species delimitation and evolutionary history of Pseudotetracha tiger beetles (Coleoptera: Cicindelidae: Megacephalini) from Australian salt lakes.

    Science.gov (United States)

    López-López, Alejandro; Hudson, Peter; Galián, José

    2016-08-01

    The Australian salt lakes are a natural archipelago-like laboratory for investigating evolutionary and population processes. Their environmental conditions have not undergone relevant changes since the aridification of Australia 10-5 million years ago. The genus Pseudotetracha, a group of nocturnal tiger beetles found on these remote salt lakes, includes 20 described species. Recent studies based on molecular markers and cytogenetics hinted at the existence of cryptic species within this group. Here we use various species delimitation algorithms to detect a high number of cryptic and undescribed taxa, and challenge the validity of the taxonomic characters traditionally used for discerning species in this group. Our analyses show that the divergence dates of the clades, between 10 and 5 million years ago, correspond to the period in which Australia was undergoing an aridification process that probably isolated the ancestral Pseudotetracha populations to individual lakes or palaeodrainage basins. This implies an important role of the isolation, produced by the aridification of Australia, in the speciation and divergence of Pseudotetracha, which underwent a remarkable radiation as the populations became geographically restricted. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Environmental imbalance in salt lake Urmia, NW Iran: Anthropogenic and climate impact on the largest lake in the Middle East

    Science.gov (United States)

    Sharifi, A.; Pourmand, A.; Peterson, L. C.; Haeri-Ardakani, O.; Pourkerman, M.; Lahijani, H. A.

    2013-12-01

    Lake Urmia is located at the lowest area of a closed-continental drainage basin in NW Iran. At an elevation of 1267m (amsl), it is the third largest saline lake on earth. The geological setting of the lake is quite diverse and its drainage basin is comprised of a variety of rock formations with different ages, ranging from Precambrian metamorphic complexes to Holocene mud deposits. Since 1995, onsite measurements and satellite altimetry have shown that the mean annual lake level has progressively dropped by as much as nine meters. Although most of the water loss has been attributed to the imbalance in the net annual flux from seven tributaries that drain to the lake, the primary cause(s) of such a drastic change in lake level in a relatively short period remains a matter of considerable debate. While naturally occurring imbalances that cause abrupt climate change are favored by local authorities, poor water management regulations and excessive damming throughout the drainage basin seem to have played a significant role in the lake's drastic loss of water over the last few decades. Instrumental climate data from the past 60 years, which show 9-year cyclicity in regional mean air temperature, does not correspond with the drastic drop in the lake's water level. In addition, a recent study of shoreline changes over 50 years shows several major episodes of reduced lake surface area in years with the highest number of rainy days since 1995. These observations suggest that the progressive imbalance in water availability to the lake is more likely caused by anthropogenic activities, rather than regional climate variability. The human impact on the Lake Urmia environment is not limited to reduced water input; imbalance in evaporation and sedimentation patterns quickly followed construction of a dike-type causeway across Lake Urmia in the early 1980s. In order to study the long-term impact of potential forcing factor(s), we have generated a high-resolution, multi proxy

  17. Biogeochemical and hydrologic processes controlling mercury cycling in Great Salt Lake, Utah

    Science.gov (United States)

    Naftz, D.; Kenney, T.; Angeroth, C.; Waddell, B.; Darnall, N.; Perschon, C.; Johnson, W. P.

    2006-12-01

    Great Salt Lake (GSL), in the Western United States, is a terminal lake with a highly variable surface area that can exceed 5,100 km2. The open water and adjacent wetlands of the GSL ecosystem support millions of migratory waterfowl and shorebirds from throughout the Western Hemisphere, as well as a brine shrimp industry with annual revenues exceeding 70 million dollars. Despite the ecologic and economic significance of GSL, little is known about the biogeochemical cycling of mercury (Hg) and no water-quality standards currently exist for this system. Whole water samples collected since 2000 were determined to contain elevated concentrations of total Hg (100 ng/L) and methyl Hg (33 ng/L). The elevated levels of methyl Hg are likely the result of high rates of SO4 reduction and associated Hg methylation in persistently anoxic areas of the lake at depths greater than 6.5 m below the water surface. Hydroacoustic equipment deployed in this anoxic layer indicates a "conveyor belt" flow system that can distribute methyl Hg in a predominantly southerly direction throughout the southern half of GSL (fig. 1, URL: http://users.o2wire.com/dnaftz/Dave/AGU-abs-figs- AUG06.pdf). Periodic and sustained wind events on GSL may result in transport of the methyl Hg-rich anoxic water and bottom sediments into the oxic and biologically active regions. Sediment traps positioned above the anoxic brine interface have captured up to 6 mm of bottom sediment during cumulative wind-driven resuspension events (fig. 2, URL:http://users.o2wire.com/dnaftz/Dave/AGU-abs-figs-AUG06.pdf). Vertical velocity data collected with hydroacoustic equipment indicates upward flow > 1.5 cm/sec during transient wind events (fig. 3, URL:http://users.o2wire.com/dnaftz/Dave/AGU-abs-figs-AUG06.pdf). Transport of methyl Hg into the oxic regions of GSL is supported by biota samples. The median Hg concentration (wet weight) in brine shrimp increased seasonally from the spring to fall time period and is likely a

  18. Phylogenetic appraisal of antagonistic, slow growing actinomycetes isolated from hypersaline inland solar salterns at Sambhar salt Lake, India

    Directory of Open Access Journals (Sweden)

    Polpass eArul Jose

    2013-07-01

    Full Text Available Inland solar salterns established in the vicinity of Sambhar Lake are extreme saline environments with high salinity and alkalinity. In view of the fact that microbes inhabiting such extreme saline environments flourish the contemporary bioprospecting, it was aimed to selectively isolate slow growing and rare actinomycetes from the unexplored solar salterns. A total of 14 slow growing actinomycetes were selectively isolated from three composite soil samples of inland solar salterns. Among the isolates, four groups were formed according to similarity of the banding patterns obtained by amplified ribosomal DNA restriction analysis (ARDRA. A subset of representative isolates for each ARDRA group was identified using 16S rDNA sequence based phylogenetic analysis and subsequently the entire isolates were assigned under three different genera; Streptomyces, Pseudonocardia and Actinoalloteichus. The genus Streptomyces was found to be the dominant among the isolates. Furthermore, rare actinomycete genus Actinoalloteichus was isolated for the first time from solar saltern. Determination of salt-tolerance revealed that certain level of salt-tolerance and moderate halophilism occurs among the actinomycetes isolated from the inland salterns. In addition, all the acinomycetes were screened in two levels to unravel their ability to produce antimicrobial compounds. Significant antimicrobial activity was found among the actinomycetes against a range of bacteria and fungi to worth further characterization of these persuasive actinomycetes and their antimicrobial secondary metabolites. In a nutshell, this study offered a first interesting insight on occurrence of antagonistic rare actinomycetes and streptomycetes in inland solar salterns associated with Sambhar salt Lake.

  19. Pesticides in Ichkeul Lake-Bizerta Lagoon Watershed in Tunisia: use, occurrence, and effects on bacteria and free-living marine nematodes.

    Science.gov (United States)

    Salem, Fida Ben; Said, Olfa Ben; Aissa, Patricia; Mahmoudi, Ezzeddine; Monperrus, Mathilde; Grunberger, Olivier; Duran, Robert

    2016-01-01

    This study aimed to identify the most commonly used agricultural pesticides around Ichkeul Lake-Bizerta Lagoon watershed. First survey of pesticide use on agricultural watershed was performed with farmers, Regional Commissioner for Agricultural Development, and pesticide dealers. Then, sediment contamination by pesticides and response of benthic communities (bacteria and free-living marine nematode) were investigated. The analysis of 22 active organochlorine pesticides in sediments was performed according to quick, easy, cheap, effective, rugged, and safe (QuEChERS) method, biodiversity of indigenous bacterial community sediment was determined by terminal restriction fragment length polymorphism (T-RFLP), and free-living marine nematodes were counted. The results of the field survey showed that iodosulfuron, mesosulfuron, 2,4-dichlorophenoxyacetic acid (2,4 D), glyphosate, and fenoxaprops were the most used herbicides, tebuconazole and epoxiconazole the most used fungicides, and deltamethrin the most used insecticide. Sixteen organochlorine pesticide compounds among the 22 examined were detected in sediments up to 2 ppm in Ichkeul Lake, endrin, dieldrin, and hexachlorocyclohexane being the most detected molecules. The most pesticide-contaminated site in the lake presented the higher density of nematode, but when considering all sites, no clear correlation with organochlorine pesticide (OCP) content could be established. The bacterial community structure in the most contaminated site in the lake was characterized by the terminal restriction fragments (T-RFs) 97, 146, 258, 285, and 335 while the most contaminated site in the lagoon was characterized by the T-RFs 54, 263, 315, 403, and 428. Interestingly, T-RFs 38 and 143 were found in the most contaminated sites of both lake and lagoon ecosystems, indicating that they were resistant to OCPs and able to cope with environmental fluctuation of salinity. In contrast, the T-RFs 63, 100, 118, and 381 in the lake and the T

  20. Southern Tunisia, Central Mediterranean

    African Journals Online (AJOL)

    GREGORY

    2010-09-13

    Sep 13, 2010 ... Length-weight relationships (LWR) were estimated for 13 fish species which are of economic relevance in the commercial fisheries of the Gulf of Gabes (southern Tunisia). A total of 2403 fish specimens were sampled with several fishing gears from October 2008 to September 2009. The sample size ranged ...

  1. Organ transplantation in Tunisia.

    Science.gov (United States)

    El Matri, Aziz; Ben Abdallah, Taieb

    2015-04-01

    Kidney transplants were first performed in Tunisia in 1986, and transplants soon extended to other organs including the heart, liver, and pancreas. Live-related donor and deceased-donor kidney transplants were both began in the summer of 1986. An organ procurement and transplant law was passed in March 1991, and the National Centre for Advancement of Organ Transplantation was created in 1995. The number of transplantation units has increased to 7 throughout the country, and the yearly transplant number has progressively increased to 139 in 2010, including 20% from deceased kidney donors. Despite these gains, the need continues to grow. Heart transplants began in January 1993, and Tunisia and Jordan are currently the only Arab countries where it is practiced. However, only 16 patients have received a heart transplant as of 2004, and the number of recipients has decreased in the past 10 years. Liver transplants are rare in other Arab countries, but began in Tunisia in January 1998. Over 10 years, 38 patients benefited from this procedure. After a few years of stagnation, the number of liver transplants is increasing. While all types of transplantation are needed, kidney transplantation is a priority in Tunisia. The target is to perform 400 transplants annually, which would require a long-term strategy to provide full financial coverage using the National Health Insurance Funds in both the public and private sectors.

  2. IDRC in Tunisia

    International Development Research Centre (IDRC) Digital Library (Canada)

    of economic research supported by. IDRC from 2006 to 2009 ... to improve farming and herding conditions by identifying the best ... sites. But there are regional differences in contributions to such sites, with relative newcomers to the Web underrepresented. Using Wikipedia as a case study, researchers in Tunisia, the United ...

  3. A MAP MASH-UP APPLICATION: INVESTIGATION THE TEMPORAL EFFECTS OF CLIMATE CHANGE ON SALT LAKE BASIN

    Directory of Open Access Journals (Sweden)

    O. S. Kirtiloglu

    2016-06-01

    Full Text Available The main purpose of this paper is to investigate climate change effects that have been occurred at the beginning of the twenty-first century at the Konya Closed Basin (KCB located in the semi-arid central Anatolian region of Turkey and particularly in Salt Lake region where many major wetlands located in and situated in KCB and to share the analysis results online in a Web Geographical Information System (GIS environment. 71 Landsat 5-TM, 7-ETM+ and 8-OLI images and meteorological data obtained from 10 meteorological stations have been used at the scope of this work. 56 of Landsat images have been used for extraction of Salt Lake surface area through multi-temporal Landsat imagery collected from 2000 to 2014 in Salt lake basin. 15 of Landsat images have been used to make thematic maps of Normalised Difference Vegetation Index (NDVI in KCB, and 10 meteorological stations data has been used to generate the Standardized Precipitation Index (SPI, which was used in drought studies. For the purpose of visualizing and sharing the results, a Web GIS-like environment has been established by using Google Maps and its useful data storage and manipulating product Fusion Tables which are all Google’s free of charge Web service elements. The infrastructure of web application includes HTML5, CSS3, JavaScript, Google Maps API V3 and Google Fusion Tables API technologies. These technologies make it possible to make effective “Map Mash-Ups” involving an embedded Google Map in a Web page, storing the spatial or tabular data in Fusion Tables and add this data as a map layer on embedded map. The analysing process and map mash-up application have been discussed in detail as the main sections of this paper.

  4. Issues of scale, location and geologic terrain related to Salt Lake City and Baltimore-Washington metropolitan areas

    Science.gov (United States)

    Cleaves, E.T.; Godfrey, A.E.; ,

    2004-01-01

    Planning and development of expanding metropolitan regions require consideration of earth science issues related to issues involving scale, space (location), geologic terrain and physiographic units, and information transfer. This paper explores these matters with examples from the Salt Lake City, Utah area and Mid-Atlantic region of Baltimore-Washington that include water supply and natural hazards (earthquakes, landslides, and sinkholes.) Information transfer methods using physiographic units at national, regional, local and site scales serve to communicate relevant geologic constraint and natural resource information.

  5. Guide to user modification of a three-dimensional digital ground-water model for Salt Lake Valley, Utah

    Science.gov (United States)

    Seiler, R.L.; Waddell, K.M.

    1986-01-01

    A digital-computer model was calibrated to simulate, in three dimensions, the ground-water flow in the principal and shallow-unconfined aquifers in Salt Lake Valley, Utah. The model can be used to predict water-level and waterbudget changes that would be caused by changes in well recharge or discharge. This report shows how a user can revise the input data so that recharging or discharging wells may be simulated and how stress-period intervals can be varied to simulate different periods of recharge or discharge.

  6. Late quaternary changes in lakes, vegetation, and climate in the Bonneville Basin reconstructed from sediment cores from Great Salt Lake: Chapter 11

    Science.gov (United States)

    Thompson, Robert S.; Oviatt, Charles G.; Honke, Jeffrey S.; McGeehin, John

    2016-01-01

    Sediment cores from Great Salt Lake (GSL) provide the basis for reconstructing changes in lakes, vegetation, and climate for the last ~ 40 cal ka. Initially, the coring site was covered by a shallow saline lake and surrounded by Artemisia steppe or steppe-tundra under a cold and dry climate. As Lake Bonneville began to rise (from ~ 30 to 28 cal ka), Pinus and subalpine conifer pollen percentages increased and Artemisia declined, suggesting the onset of wetter conditions. Lake Bonneville oscillated near the Stansbury shoreline between ~ 26 and ~ 24 cal ka, rose to the Bonneville shoreline by ~ 18 cal ka, and then fell to the Provo shoreline, which it occupied until ~ 15 cal ka. Vegetation changed during this time span, albeit not always with the same direction or amplitude as the lake. The pollen percentages of Pinus and subalpine conifers were high from ~ 25 to 21.5 cal ka, indicating cool and moist conditions during the Stansbury oscillation and for much of the rise toward the Bonneville shoreline. Pinus percentages then decreased and Artemisia became codominant, suggesting drier and perhaps colder conditions from ~ 21 to ~ 15 cal ka, when Lake Bonneville was at or near its highest levels.Lake Bonneville declined to a low level by ~ 13 cal ka, while Pinus pollen percentages increased, indicating that conditions remained cooler and moister than today. During the Younger Dryas interval, the brief Gilbert episode rise in lake level was followed by a shallow lake with a stratified water column. This lake rise occurred as Pinus pollen percentages were declining and those of Artemisia were rising (reflecting increasingly dry conditions), after which Artemisia pollen was at very high levels (suggesting cold and dry conditions) for a brief period.Since ~ 10.6 cal ka lacustrine conditions have resembled those of present-day GSL. Pollen spectra for the period from ~ 10.6 to 7.2 cal ka have low levels of conifer pollen and high (for the

  7. Halobellus inordinatus sp. nov., from a marine solar saltern and an inland salt lake of China.

    Science.gov (United States)

    Qiu, Xing-Xing; Mou, Yun-Zhuang; Zhao, Mei-Lin; Zhang, Wen-Jiao; Han, Dong; Ren, Min; Cui, Heng-Lin

    2013-11-01

    Two halophilic archaeal strains, YC20(T) and XD15, were isolated from a marine solar saltern and an inland salt lake in China. Both had pleomorphic cells that lysed in distilled water, stained Gram-negative and formed red-pigmented colonies. They were neutrophilic, requiring at least 100 g NaCl l(-1) and 0.5-95 g MgCl2 l(-1) for growth at the optimum growth temperature of 37 °C. The major polar lipids of the two strains were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS) and two major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1) and mannosyl glucosyl diether (DGD-1), respectively. Trace amounts of two unidentified glycolipids were also detected. The 16S rRNA gene sequences of the two strains were 99.5 % identical and showed 94.0-95.9 % similarity to the most closely related members of the genus Halobellus of the family Halobacteriaceae. The rpoB' gene sequence similarity between strains YC20(T) and XD15 was 98.2 % and these sequences showed 89.6-92.8 % similarity to those of the most closely related members of the genus Halobellus. The DNA G+C contents of strains YC20(T) and XD15 were 65.8 mol% and 65.4 mol%, respectively. The DNA-DNA hybridization value between strain YC20(T) and strain XD15 was 92 %, and the two strains showed low DNA-DNA relatedness to members of the genus Halobellus. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains YC20(T) and XD15 represent a novel species of the genus Halobellus, for which the name Halobellus inordinatus sp. nov. is proposed. The type strain is YC20(T) ( = CGMCC 1.12120(T) = JCM 18361(T)) and the other strain is XD15 ( = CGMCC 1.12236 = JCM 18648).

  8. Halobacillus dabanensis sp. nov. and Halobacillus aidingensis sp. nov., isolated from salt lakes in Xinjiang, China.

    Science.gov (United States)

    Liu, W Y; Zeng, J; Wang, L; Dou, Y T; Yang, S S

    2005-09-01

    Two moderately halophilic spore-forming bacteria were isolated from salt lakes in the Xinjiang region of China. The two strains, designated AD-6(T) and D-8(T), were aerobic, Gram-positive, rod-shaped and motile by means of peritrichous flagella. Strains AD-6(T) and D-8(T) grew in the presence of 0.5-20% and 0.5-25% (w/v) NaCl in complex medium, respectively. Their cell-wall peptidoglycan was of the L-Orn-D-Asp type. The major menaquinone found in both strains was menaquinone-7 (MK-7). The fatty acid profile contained a large amount of branched fatty acids; the main fatty acids were anteiso-C(15:0), anteiso-C(17:0), iso-C(15:0) and iso-C(16:0). The DNA G+C content of strains D-8(T) and AD-6(T) was 41.4 and 42.2 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains D-8(T) and AD-6(T) were located in the genus Halobacillus. Levels of 16S rRNA gene sequence similarity between the isolated strains and the type strains of Halobacillus species were in the range 96.2-99.5%. DNA-DNA relatedness values of 17.0-52.2% were found between the two strains and other Halobacillus species. The DNA-DNA relatedness value between D-8(T) and AD-6(T) was 50.6%. On the basis of phenotypic and chemotaxonomic properties, phylogenetic analysis and genomic distinctiveness, strains D-8(T) and AD-6(T) should be placed in the genus Halobacillus as two novel species, for which the names Halobacillus dabanensis sp. nov. (type strain=JCM 12772(T)=CGMCC 1.3704(T)) and Halobacillus aidingensis sp. nov. (type strain=JCM 12771(T)=CGMCC 1.3703(T)) are proposed, respectively.

  9. Halosiccatus urmianus gen. nov., sp. nov., a haloarchaeon from a salt lake.

    Science.gov (United States)

    Mehrshad, Maliheh; Amoozegar, Mohammad Ali; Makhdoumi, Ali; Fazeli, Seyed Abolhassan Shahzadeh; Farahani, Homa; Asadi, Basaer; Schumann, Peter; Ventosa, Antonio

    2016-02-01

    A novel, orange-pigmented, halophilic archaeon, strain DC8T, was isolated from Urmia salt lake in north-west Iran. The cells of strain DC8T were non-motile and pleomorphic, from small rods to triangular or disc shaped. The novel strain needed at least 2.5 M NaCl and 0.02 M MgCl2 for growth. Optimal growth was achieved at 4.0 M NaCl and 0.1 M MgCl2. The optimum pH and temperature for growth were pH 7.5 and 45 °C, respectively, and it was able to grow over a pH range of 7.0 to 8.5 and a temperature range of 25 to 55 °C. Analysis of the 16S rRNA gene sequence showed that strain DC8T was a member of the family Halobacteriaceae; however, its similarity was as low as 90.1 %, 89.3 % and 89.1 % to the most closely related haloarchaeal taxa, including type species of members of the genera Halosimplex, Halobaculum and Halomicrobium, respectively. The G+C content of its DNA was 68.1 mol%. Polar lipid analyses revealed that strain DC8T contained phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and phosphatidic acid. One unknown phospholipid, two major glycolipids and one minor glycolipid were also detected. The only quinone present was MK-8 (II-H2). The physiological, biochemical and phylogenetic differences between strain DC8T and other extremely halophilic archaeal genera with validly published names supported that this strain represents a novel species of a new genus within the family Halobacteriaceae, for which the name Halosiccatus urmianus gen. nov., sp. nov. is proposed. The type strain is strain DC8T ( = IBRC-M 10911T = CECT 8793T).

  10. Effect of salinity on mercury methylating benthic microbes and their activities in Great Salt Lake, Utah

    Science.gov (United States)

    Boyd, Eric S.; Yu, Ri-Qing; Barkay, Tamar; Hamilton, Trinity L.; Baxter, Bonnie K.; Naftz, David L.; Marvin-DiPasquale, Mark

    2017-01-01

    Surface water and biota from Great Salt Lake (GSL) contain some of the highest documented concentrations of total mercury (THg) and methylmercury (MeHg) in the United States. In order to identify potential biological sources of MeHg and controls on its production in this ecosystem, THg and MeHg concentrations, rates of Hg(II)-methylation and MeHg degradation, and abundances and compositions of archaeal and bacterial 16 rRNA gene transcripts were determined in sediment along a salinity gradient in GSL. Rates of Hg(II)-methylation were inversely correlated with salinity and were at or below the limits of detection in sediment sampled from areas with hypersaline surface water. The highest rates of Hg(II)-methylation were measured in sediment with low porewater salinity, suggesting that benthic microbial communities inhabiting less saline environments are supplying the majority of MeHg in the GSL ecosystem. The abundance of 16S rRNA gene transcripts affiliated with the sulfate reducer Desulfobacterium sp. was positively correlated with MeHg concentrations and Hg(II)-methylation rates in sediment, indicating a potential role for this taxon in Hg(II)-methylation in low salinity areas of GSL. Reactive inorganic Hg(II) (a proxy used for Hg(II) available for methylation) and MeHg concentrations were inversely correlated with salinity. Thus, constraints imposed by salinity on Hg(II)-methylating populations and the availability of Hg(II) for methylation are inferred to result in higher MeHg production potentials in lower salinity environments. Benthic microbial MeHg degradation was also most active in lower salinity environments. Collectively, these results suggest an important role for sediment anoxia and microbial sulfate reducers in the production of MeHg in low salinity GSL sub-habitats and may indicate a role for salinity in constraining Hg(II)-methylation and MeHg degradation activities by influencing the availability of Hg(II) for methylation.

  11. The Great Salt Lake: A Barometer of Low Frequency Climate Variability

    OpenAIRE

    Lall, Upmanu; Mann, Michael

    1994-01-01

    Low frequency (interannual or longer period) climatic variability is of interest bacause of its sugnificance for the understanding and prediction of protracted climatic anomalies. Closed basin lakes are sensitive to long term climatic fluctuations and integrate out high frequency variability. It is thus natural to examine the records of such lakes to better understand long term climate dynamics. Here we use Singul...

  12. Salt Lake City Area Integrated Projects Electric Power Marketing. Draft environmental impact statement: Volume 4, Appendixes B-D

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    The Salt Lake City Area Office of the Western Area Power Administration (Western) markets electricity produced at hydroelectric facilities operated by the Bureau of Reclamation. The facilities are known collectively as the Salt Lake City Area Integrated Projects (SLCA/IP) and include dams equipped for power generation on the Green, Gunnison, Rio Grande, and Colorado rivers and on Deer and Plateau creeks in the states of Wyoming, Utah, Colorado, Arizona, and New Mexico. Of these facilities, only the Glen Canyon Unit, the Flaming Gorge Unit, and the Aspinall Unit (which includes Blue Mesa, Morrow Point, and Crystal dams;) are influenced by Western power scheduling and transmission decisions. The EIS alternatives, called commitment-level alternatives, reflect combinations of capacity and energy that would feasibly and reasonably fulfill Westerns firm power marketing responsibilities, needs, and statutory obligations. The viability of these alternatives relates directly to the combination of generation capability of the SLCA/IP with energy purchases and interchange. The economic and natural resource assessments in this environmental impact statement (EIS) include an analysis of commitment-level alternatives. Impacts of the no-action alternative are also assessed. Supply options, which include combinations of electrical power purchases and hydropower operational scenarios reflecting different operations of the dams, are also assessed. The EIS evaluates the impacts of these scenarios relative to socioeconomics, air resources, water resources, ecological resources, cultural resources, land use, recreation, and visual resources.

  13. Use of Landsat Land Surface Temperature and Vegetation Indices for Monitoring Drought in the Salt Lake Basin Area, Turkey

    Science.gov (United States)

    Orhan, Osman; Ekercin, Semih; Dadaser-Celik, Filiz

    2014-01-01

    The main purpose of this paper is to investigate multitemporal land surface temperature (LST) changes by using satellite remote sensing data. The study included a real-time field work performed during the overpass of Landsat-5 satellite on 21/08/2011 over Salt Lake, Turkey. Normalized vegetation index (NDVI), vegetation condition index (VCI), and temperature vegetation index (TVX) were used for evaluating drought impact over the region between 1984 and 2011. In the image processing step, geometric and radiometric correction procedures were conducted to make satellite remote sensing data comparable with in situ measurements carried out using thermal infrared thermometer supported by hand-held GPS. The results showed that real-time ground and satellite remote sensing data were in good agreement with correlation coefficient (R 2) values of 0.90. The remotely sensed and treated satellite images and resulting thematic indices maps showed that dramatic land surface temperature changes occurred (about 2°C) in the Salt Lake Basin area during the 28-year period (1984–2011). Analysis of air temperature data also showed increases at a rate of 1.5–2°C during the same period. Intensification of irrigated agriculture particularly in the southern basin was also detected. The use of water supplies, especially groundwater, should be controlled considering particularly summer drought impacts on the basin. PMID:24587709

  14. Salt lakes of La Mancha (Central Spain): A hot spot for tiger beetle (Carabidae, Cicindelinae) species diversity.

    Science.gov (United States)

    Rodríguez-Flores, Paula C; Gutiérrez-Rodríguez, Jorge; Aguirre-Ruiz, Ernesto F; García-París, Mario

    2016-01-01

    The tiger beetle assemblage of the wetlands of La Mancha (central Spain) comprises nine species: Calomera littoralis littoralis, Cephalota maura maura, Cephalota circumdata imperialis, Cephalota dulcinea, Cicindela campestris campestris, Cicindela maroccana, Cylindera paludosa, Lophyra flexuosa flexuosa, and Myriochila melancholica melancholica. This assemblage represents the largest concentration of tiger beetles in a single 1º latitude / longitude square in Europe. General patterns of spatial and temporal segregation among species are discussed based on observations of 1462 specimens registered during an observation period of one year, from April to August. The different species of Cicindelini appear to be distributed over space and time, with little overlapping among them. Three sets of species replace each other phenologically as the season goes on. Most of the species occupy drying or dried salt lakes and salt marshes, with sparse vegetation cover. Spatial segregation is marked in terms of substrate and vegetation use. Calomera littoralis and Myriochila melancholica have been observed mainly on wet soils; Cephalota circumdata on dry open saline flats; Cephalota dulcinea and Cylindera paludosa in granulated substrates with typical halophytic vegetation; Cephalota maura is often present in man-modified areas. Cephalota circumdata and Cephalota dulcinea are included as species of special interest in the list of protected species in Castilla-La Mancha. Conservation problems for the Cicindelini assemblage arise from agricultural activities and inadequate use of sport vehicles. Attempts at restoring the original habitat, supressing old semi-industrial structures, may affect the spatial heterogeneity of the lakes, and have an effect on Cicindelinae diversity.

  15. Salt Lake City Area Integrated Projects Electric Power Marketing. Draft environmental impact statement: Volume 3, Appendix A

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    The Salt Lake City Area Office of the Western Area Power Administration (Western) markets electricity produced at hydroelectric facilities operated by the Bureau of Reclamation. The facilities are known collectively as the Salt Lake City Area Integrated Projects (SLCA/IP) and include dams equipped for power generation on the Green, Gunnison, Rio Grande, and Colorado rivers and on Deer and Plateau creeks in the states of Wyoming, Utah, Colorado, Arizona, and New Mexico. Of these facilities, only the Glen Canyon Unit, the Flaming Gorge Unit, and the Aspinall Unit (which includes Blue Mesa, Morrow Point, and Crystal dams;) are influenced by Western power scheduling and transmission decisions. The EIS alternatives, called commitment-level alternatives, reflect combinations of capacity and energy that would feasibly and reasonably fulfill Westerns firm power marketing responsibilities, needs, and statutory obligations. The viability of these alternatives relates directly to the combination of generation capability of the SLCA/IP with energy purchases and interchange. The economic and natural resource assessments in this environmental impact statement (EIS) include an analysis of commitment-level alternatives. Impacts of the no-action alternative are also assessed. Supply options, which include combinations of electrical power purchases and hydropower operational scenarios reflecting different operations of the dams, are also assessed. The EIS evaluates the impacts of these scenarios relative to socioeconomics, air resources, water resources, ecological resources, cultural resources, land use, recreation, and visual resources.

  16. Salt Lake City Area Integrated Projects Electric Power Marketing. Draft environmental impact statement: Volume 2, Sections 1-16

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    The Salt Lake City Area Office of the Western Area Power Administration (Western) markets electricity produced at hydroelectric facilities operated by the Bureau of Reclamation. The facilities are known collectively as the Salt Lake City Area Integrated Projects (SLCA/IP) and include dams equipped for power generation on the Green, Gunnison, Rio Grande, and Colorado rivers and on Deer and Plateau creeks in the states of Wyoming, Utah, Colorado, Arizona, and New Mexico. Of these facilities, only the Glen Canyon Unit, the Flaming Gorge Unit, and the Aspinall Unit (which includes Blue Mesa, Morrow Point, and Crystal dams;) are influenced by Western power scheduling and transmission decisions. The EIS alternatives, called commitment-level alternatives, reflect combinations of capacity and energy that would feasibly and reasonably fulfill Westerns firm power marketing responsibilities, needs, and statutory obligations. The viability of these alternatives relates directly to the combination of generation capability of the SLCA/IP with energy purchases and interchange. The economic and natural resource assessments in this environmental impact statement (EIS) include an analysis of commitment-level alternatives. Impacts of the no-action alternative are also assessed. Supply options, which include combinations of electrical power purchases and hydropower operational scenarios reflecting different operations of the dams, are also assessed. The EIS evaluates the impacts of these scenarios relative to socioeconomics, air resources, water resources, ecological resources, cultural resources, land use, recreation, and visual resources.

  17. Relationships between lake-level changes and water and salt budgets in the Dead Sea during extreme aridities in the Eastern Mediterranean

    Science.gov (United States)

    Kiro, Yael; Goldstein, Steven L.; Garcia-Veigas, Javier; Levy, Elan; Kushnir, Yochanan; Stein, Mordechai; Lazar, Boaz

    2017-04-01

    Thick halite intervals recovered by the Dead Sea Deep Drilling Project cores show evidence for severely arid climatic conditions in the eastern Mediterranean during the last three interglacials. In particular, the core interval corresponding to the peak of the last interglacial (Marine Isotope Stage 5e or MIS 5e) contains ∼30 m of salt over 85 m of core length, making this the driest known period in that region during the late Quaternary. This study reconstructs Dead Sea lake levels during the salt deposition intervals, based on water and salt budgets derived from the Dead Sea brine composition and the amount of salt in the core. Modern water and salt budgets indicate that halite precipitates only during declining lake levels, while the amount of dissolved Na+ and Cl- accumulates during wetter intervals. Based on the compositions of Dead Sea brines from pore waters and halite fluid inclusions, we estimate that ∼12-16 cm of halite precipitated per meter of lake-level drop. During periods of halite precipitation, the Mg2+ concentration increases and the Na+/Cl- ratio decreases in the lake. Our calculations indicate major lake-level drops of ∼170 m from lake levels of 320 and 310 m below sea level (mbsl) down to lake levels of ∼490 and ∼480 mbsl, during MIS 5e and the Holocene, respectively. These lake levels are much lower than typical interglacial lake levels of around 400 mbsl. These lake-level drops occurred as a result of major decreases in average fresh water runoff, to ∼40% of the modern value (pre-1964, before major fresh water diversions), reflecting severe droughts during which annual precipitation in Jerusalem was lower than 350 mm/y, compared to ∼600 mm/y today. Nevertheless, even during salt intervals, the changes in halite facies and the occurrence of alternating periods of halite and detritus in the Dead Sea core stratigraphy reflect fluctuations between drier and wetter conditions around our estimated average. The halite intervals include

  18. Household indebtedness in Tunisia

    OpenAIRE

    Abid, Lobna; Zouari Dorra; Zouari Ghorbel Sonia

    2012-01-01

    This paper aims to analyze the development of household indebtedness in Tunisia and its microeconomic determinants. The probit method was used to identify the determinants of household indebtedness with reference to gender. The results show that the Tunisian household indebtedness is in continuous increase and each type of credit is associated with specific determinants. The findings show that only some variables are significant in explaining the differences between the number of credit.

  19. [Imported malaria in Tunisia].

    Science.gov (United States)

    Bouratbine, A; Chahed, M K; Aoun, K; Krida, G; Ayari, S; Ben Ismail, R

    1998-01-01

    Thanks to the national programme of malaria eradication carried out between 1968 and 1972, there has been no active transmission of the parasitosis in Tunisia since the last indigenous case in 1979. Since 1980, with the increase in international exchanges especially with sub-Saharian countries, only imported cases of malaria have been reported in Tunisia. A retrospective and thorough survey of malaria cases diagnosed in the laboratory of parasitology of the Pasteur Institute in Tunis from 1980 to 1995 determined the epidemiological characteristics of this imported parasitosis. All in all, during the sixteen years following eradication, 245 cases were registered. The majority of cases (86.2%) was diagnosed by a systematic control of groups at risk within the national programme of malaria eradication. The remaining 13.8% cases sought medical advice when clinical symptoms appeared after their return from endemic countries. The population most affected by imported malaria were men (sex-ratio: 6.8) aged between 20 and 40 years (76% of cases); 38% were Tunisians having sojourned in an endemic country, essentially students from sub-Saharian Africa. The presumed country of contamination was African in 92.7% of the cases. Entrance into Tunisia by patients was mainly by air; 4% of the registered cases had come by land from Algeria. Sound knowledge of the epidemiological characteristics of imported malaria would make for a better follow-up of the affected population and thus reduce the probability of repeated transmission.

  20. Cutaneous tuberculosis in Tunisia.

    Science.gov (United States)

    Abdelmalek, R; Mebazaa, A; Berriche, A; Kilani, B; Ben Osman, A; Mokni, M; Tiouiri Benaissa, H

    2013-09-01

    Tuberculosis is endemic in Tunisia. Pulmonary tuberculosis is the most common presentation in our country. Cutaneous presentations are rare (1-2% of cases). The diagnosis of cutaneous tuberculosis (CT) is difficult. Histological and clinical presentations are polymorphous, many differential diagnoses are available, and it is difficult to isolate Mycobacterium. We had for aim to study the epidemiological and clinical features of CT in Tunisia, and to compare presentations before and after 1990. We conducted a retrospective study between January 1991 and December 2011, in which we included all cases of CT observed at the Infectious Diseases and Dermatology Units of the Tunis la Rabta Hospital. Hundred and thirty-seven patients were included, with a mean age of 43.8years; 72.3% were female patients. Hundred and fifty locations were observed, most of which on the head and neck. Scrofuloderma was the most frequent presentation, observed in 65% of cases. The diagnosis was confirmed by histology and/or microbiology in 75.8% of cases. The treatment was prescribed for a mean 11.3months, leading to full recovery in most cases. CT is still reported in Tunisia. The diagnosis relies mainly on histology. Controlling this mutilating tuberculosis requires a global control of this disease, and especially lymph node location, given the high rate of scrofuloderma. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  1. Stable isotope record of Holocene climate and ecological change from brine shrimp cyst chitin for the Great Salt Lake, UT

    Science.gov (United States)

    Nielson, K. E.; Bowen, G. J.

    2009-12-01

    We present a record of oxygen and hydrogen isotopes in brine shrimp cysts from the Great Salt Lake, a terminal lake in the Great Basin, US. Water balance for the region is influenced by strength of the El Niño in Pacific and by the strength of the summer monsoon. Brine shrimp cysts are a novel proxy for isotope reconstruction, and allow reconstruction of water isotopes (oxygen, hydrogen) and ecology (hydrogen). Oxygen isotopes in chitin respond to water, while both diet and growth water contribute to hydrogen isotopes, allowing reconstruction of both environmental and ecological information from a single molecule. Values of δ18O decrease from about +15‰ to about +11‰ over course of the 8000 year record. This may suggest the importance of snow melt increased over the Holocene, or it may suggest lake is larger today than it was in mid-Holocene. Hydrogen isotopes are relatively stable for most of record, fluctuating around -140‰. Modeled hydrogen isotopes in food, also stable in the beginning of the record at about -150‰, become much heavier, shifting toward about -75‰ starting about 5000 ybp. This may suggest a shift from a primarily aquatic diet in the Mid-Holocene to a diet with a greater contribution of terrestrial material later in the Holocene. These observations agree broadly with previous inferences of a warm Mid-Holocene and associated low terrestrial productivity, followed by a more moist, and consequently more productive Late Holocene.

  2. Desulfonatronobacter acetoxydans sp. nov.,: a first acetate-oxidizing, extremely salt-tolerant alkaliphilic SRB from a hypersaline soda lake.

    Science.gov (United States)

    Sorokin, D Y; Chernyh, N A; Poroshina, M N

    2015-09-01

    Recent intensive microbiological investigation of sulfidogenesis in soda lakes did not result in isolation of any pure cultures of sulfate-reducing bacteria (SRB) able to directly oxidize acetate. The sulfate-dependent acetate oxidation at haloalkaline conditions has, so far, been only shown in two syntrophic associations of novel Syntrophobacteraceae members and haloalkaliphilic hydrogenotrophic SRB. In the course of investigation of one of them, obtained from a hypersaline soda lake in South-Western Siberia, a minor component was observed showing a close relation to Desulfonatronobacter acidivorans--a "complete oxidizing" SRB from soda lakes. This organism became dominant in a secondary enrichment with propionate as e-donor and sulfate as e-acceptor. A pure culture, strain APT3, was identified as a novel member of the family Desulfobacteraceae. It is an extremely salt-tolerant alkaliphile, growing with butyrate at salinity up to 4 M total Na(+) with a pH optimum at 9.5. It can grow with sulfate as e-acceptor with C3-C9 VFA and also with some alcohols. The most interesting property of strain APT3 is its ability to grow with acetate as e-donor, although not with sulfate, but with sulfite or thiosulfate as e-acceptors. The new isolate is proposed as a new species Desulfonatronobacter acetoxydans.

  3. Paleolimnological and geochronological studies of salt lakes of Crimea, the Black Sea area

    Science.gov (United States)

    Subetto, D. A.; Sapelko, T. V.; Kuznetsov, D. D.; Ludikova, A. V.; Gerasimenko, N.; Stolba, V.; Bakhmutov, V.

    2009-04-01

    1. Crimea is one of the few places in the northern Black Sea region with mineral lakes with sediments that can give information about paleoclimate and environmental changes over a long time period. All of these lakes are shallow (c. 1-1.5 m), saline of marine origin (former marine bays and lagoons), the emergence of which took place in ‘historical' time (c. 5000 yrs ago). 2. The thickness of sediments is reaching up to 20-25 m. The recovery of long sediment sequences permits comparative study of the complex interactions among humans, climate and environment in the Crimea. Moreover, it provides an opportunity to establish a direct chronological link between major ethno-historical and economic processes on the one hand and climatic changes such as wet-dry circles that affected the whole area on the other. 3. Two lake sediment sequences have been recovered from the Crimean Peninsula ((Lake Saki (45° 06',8N; 33° 33',2E, water depth ca 0.8 m, recovered sediments 4.2 m) and Lake Dzharylgach(45° 34',7N; 32° 51',7E, water depth ca 0.8 m, recovered sediments 4.15 m)) during the field campaign 2005, as part of the Joint Danish-Russian-Ukraine project called "Northern Black Sea in the 1st millennium BC: human history and climate changes". In 2006, a detailed examination of the cores was carried out by the team members from the Institute of Limnology, RAS, St Petersburg, the National Taras Shevchenko University of Kyiv, and the Institute of Physics of the Earth, NASU, Kiev. The detailed examination of the cores, which includes varve counting, lithostratigraphy, geochemistry, pollen, diatom and ostracods analyses is presently being carried out. The AMS 14C dating is being processed by the Radiocarbon Laboratory, Institute of Physics and Astronomy. 4. In the both studied lakes, marine sediments overlain by mineralized lake sediments were recovered. The oldest dates from marine sediment from both studied sequences are 5500-5370 cal BP (L.Saki) and 7200-7050 cal BP (L

  4. Halorubrum rubrum sp. nov., an extremely halophilic archaeon from a Chinese salt lake.

    Science.gov (United States)

    Qiu, Xing-Xing; Zhao, Mei-Lin; Han, Dong; Zhang, Wen-Jiao; Cui, Heng-Lin

    2013-11-01

    Two halophilic archaeal strains, YC87(T) and YCA11, were isolated from Yuncheng salt lake in Shanxi, China. Cells of the two strains were observed to be pleomorphic rod-shaped, stained Gram-negative and produced red-pigmented colonies. Strain YC87(T) was able to grow at 20-50 °C (optimum 37 °C), at 1.4-4.8 M NaCl (optimum 2.1 M NaCl), at 0.05-1.0 M MgCl2 (optimum 0.3 M MgCl2) and at pH 6.0-9.0 (optimum pH 7.0) while strain YCA11 was able to grow at 20-50 °C (optimum 37 °C), at 2.1-4.8 M NaCl (optimum 3.1 M NaCl), at 0.01-0.7 M MgCl2 (optimum 0.1 M MgCl2) and at pH 6.0-9.0 (optimum pH 7.5). The cells of both isolates were observed to lyse in distilled water. The minimum NaCl concentrations that prevented cell lysis were determined to be 8 % (w/v) for strain YC87(T) and 12 % (w/v) for strain YCA11. The major polar lipids of the two strains were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and one major glycolipid chromatographically identical to sulfated mannosyl glucosyl diether; another major glycolipid and trace amounts of several unidentified lipids were also detected. The 16S rRNA gene sequences of the two strains were 99.8 % identical, showing 93.2-98.2 % similarity to members of the genus Halorubrum of the family Halobacteriaceae. The rpoB' gene similarity between strains YC87(T) and YCA11 was 99.3 % and showed 87.5-95.2 % similarity to the closest relative members of the genus Halorubrum. The DNA G+C content of strains YC87(T) and YCA11 were determined to be 64.9 and 64.5 mol%, respectively. The DNA-DNA hybridization value between strain YC20(T) and strain YC77 was 87 % and the two strains showed low DNA-DNA relatedness with Halorubrum cibi JCM 15757(T) and Halorubrum aquaticum CGMCC 1.6377(T), the most related members of the genus Halorubrum. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains YC87(T) and YCA11 represent a novel species of the

  5. [Great Salt Lake Ecosystem Wetlands and Wildlife: A prospectus for a mini-joint venture

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a general approach towards a mini-joint venture between Near River Migratory Bird Refuge and Utah State University. It is focused on the Great Salt...

  6. Ground-water resources and simulated effects of withdrawals in the East Shore area of Great Salt Lake, Utah

    Science.gov (United States)

    Clark, David W.; Appel, Cynthia L.; Lambert, Patrick M.; Puryear, Robert L.

    1990-01-01

    The ground-water resources in the East Shore area of Great Salt Lake, Utah, were studied to better define the ground-water system; to document changes in ground-water levels, quality, and storage; and to simulate effects of an increase in ground-water withdrawals. The East Shore aquifer system is in basin-fill deposits, and is primarily a confined system with unconfined parts near the mountain front.Recharge to and discharge from the East Shore aquifer system were estimated to average about 160,000 acre-feet per year during 1969-84, with minor amounts of water being removed from storage during that period.  Major sources of ground-water recharge are seepage from surface water in natural channels and irrigation canals, and subsurface inflow from consolidated rock to the basin-fill deposits. Discharge of ground water is primarily to wells, water courses, springs, and as diffuse seepage to Great Salt Lake. Average annual surface-water inflow to the study area was estimated to be 860,000 acre-feet for the period 1969-84. Annual withdrawal of ground water for municipal and industrial use increased from about 10,000 acre-feet in 1960 to more than 30,000 acre-feet in 1980 to supply a population that increased from 175,000 in 1960 to 290,000 in 1980.Long-term trends of ground-water levels indicate a steady decline at most observation wells since 1952, despite near normal or increased precipitation since the late 1960's.  Water levels declined as much as 50 feet near the principal pumping center in the east-central part of the study area. They declined as much as 35 feet more than five miles from the pumping center.  The increase in withdrawals and subsequent water-level declines have caused about 700 wells within 30 square miles to cease flowing since 1954.A numerical model of the East Shore aquifer system in the Weber Delta area was constructed and calibrated using water-level data and changes in ground-water withdrawals for 1955-85. Predictive simulations were made

  7. Great Salt Lake halophilic microorganisms as models for astrobiology: evidence for desiccation tolerance and ultraviolet irradiation resistance

    Science.gov (United States)

    Baxter, Bonnie K.; Eddington, Breanne; Riddle, Misty R.; Webster, Tabitha N.; Avery, Brian J.

    2007-09-01

    Great Salt Lake (GSL) is home to halophiles, salt-tolerant Bacteria and Archaea, which live at 2-5M NaCl. In addition to salt tolerance, GSL halophiles exhibit resistance to both ultraviolet (UV) irradiation and desiccation. First, to understand desiccation resistance, we sought to determine the diversity of GSL halophiles capable of surviving desiccation in either recently formed GSL halite crystals or GSL Artemia (brine shrimp) cysts. From these desiccated environments, surviving microorganisms were cultured and isolated, and genomic DNA was extracted from the individual species for identification by 16S rRNA gene homology. From the surface-sterilized cysts we also extracted DNA of the whole microbial population for non-cultivation techniques. We amplified the archaeal or bacterial 16S rRNA gene from all genomic DNA, cloned the cyst population amplicons, and sequenced. These sequences were compared to gene databases for determination of closest matched species. Interestingly, the isolates from the crystal dissolution are distinct from those previously isolated from GSL brine. The cyst population results reveal species not found in crystals or brine, and may indicate microorganisms that live as endosymbionts of this hypersaline arthropod. Second, we explored UV resistance in a GSL haloarchaea species, "H. salsolis." This strain resists UV irradiation an order of magnitude better than control species, all of which have intact repair systems. To test the hypothesis that halophiles have a photoprotection system, which prevents DNA damage from occurring, we designed an immunoassay to detect thymine dimers following UV irradiation. "H. salsolis" showed remarkable resistance to dimer formation. Evidence for both UV and desiccation resistance in these salt-tolerant GSL halophiles makes them well-suited as models for Astrobiological studies in pursuit of questions about life beyond earth.

  8. Carbon Isotope Ratios Of Carbon Dioxide In The Urban Salt Lake Valley, Utah USA: Source And Long-Term Monitoring Observations

    Science.gov (United States)

    Ehleringer, J.; Lai, C.; Strong, C.; Pataki, D. E.; Bowling, D. R.; Schauer, A. J.; Bush, S.

    2011-12-01

    A high-precision, decadal record of carbon isotope ratios in atmospheric carbon dioxide has been produced for the urbanized Salt Lake Valley, Utah USA. These data complement a similar time series of atmospheric carbon dioxide concentrations for different locations in the same urban region. This isotopic record includes diurnal and nocturnal observations based on flask (IRMS-based) and continuous (TDL-based) measurement systems. These data reveal repeatable diurnal and seasonal variations in the anthropogenic and biogenic carbon sources that can be used to reconstruct different source inputs. As the Salt Lake Valley is an isolated urban region, the impacts of local anthropogenic inputs can be distinguished from regional patterns as measured by NOAA at the rural Wendover monitoring station 200 km to the west of the Salt Lake Valley. Complementary data, such as vehicle exhaust, emission from power plants and household furnaces, plant and soil organic matter, are also provided to quantify the carbon isotope ratios of the predominant anthropogenic and biogenic sources within the Salt Lake Valley. The combined source and long-term observational values will be made freely available and their utility is discussed for modeling efforts including urban metabolism modeling and atmospheric trace gas modeling.

  9. Detecting agricultural to urban land use change from multi-temporal MSS digital data. [Salt Lake County, Utah

    Science.gov (United States)

    Ridd, M. K.; Merola, J. A.; Jaynes, R. A.

    1983-01-01

    Conversion of agricultural land to a variety of urban uses is a major problem along the Wasatch Front, Utah. Although LANDSAT MSS data is a relatively coarse tool for discriminating categories of change in urban-size plots, its availability prompts a thorough test of its power to detect change. The procedures being applied to a test area in Salt Lake County, Utah, where the land conversion problem is acute are presented. The identity of land uses before and after conversion was determined and digital procedures for doing so were compared. Several algorithms were compared, utilizing both raw data and preprocessed data. Verification of results involved high quality color infrared photography and field observation. Two data sets were digitally registered, specific change categories internally identified in the software, results tabulated by computer, and change maps printed at 1:24,000 scale.

  10. Baseline risk assessment of ground water contamination at the uranium mill tailings site Salt Lake City, Utah

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    This baseline risk assessment of groundwater contamination at the uranium mill tailings site near Salt Lake City, Utah, evaluates potential public health or environmental impacts resulting from ground water contamination at the former uranium ore processing site. The tailings and other contaminated material at this site were placed in a disposal cell located at Clive, Utah, in 1987 by the US Department of Energy`s Uranium Mill Tailings Remedial Action (UMTRA) Project. The second phase of the UMTRA Project is to evaluate residual ground water contamination at the former uranium processing site, known as the Vitro processing site. This risk assessment is the first site-specific document under the Ground Water Project. It will help determine the appropriate remedial action for contaminated ground water at the site.

  11. Density-stratified flow events in Great Salt Lake, Utah, USA: implications for mercury and salinity cycling

    Science.gov (United States)

    Naftz, David L.; Carling, Gregory T.; Angeroth, Cory; Freeman, Michael; Rowland, Ryan; Pazmiño, Eddy

    2014-01-01

    Density stratification in saline and hypersaline water bodies from throughout the world can have large impacts on the internal cycling and loading of salinity, nutrients, and trace elements. High temporal resolution hydroacoustic and physical/chemical data were collected at two sites in Great Salt Lake (GSL), a saline lake in the western USA, to understand how density stratification may influence salinity and mercury (Hg) distributions. The first study site was in a causeway breach where saline water from GSL exchanges with less saline water from a flow restricted bay. Near-surface-specific conductance values measured in water at the breach displayed a good relationship with both flow and wind direction. No diurnal variations in the concentration of dissolved (total and MeHg loadings was observed during periods of elevated salinity. The second study site was located on the bottom of GSL where movement of a high-salinity water layer, referred to as the deep brine layer (DBL), is restricted to a naturally occurring 1.5-km-wide “spillway” structure. During selected time periods in April/May, 2012, wind-induced flow reversals in a railroad causeway breach, separating Gunnison and Gilbert Bays, were coupled with high-velocity flow pulses (up to 55 cm/s) in the DBL at the spillway site. These flow pulses were likely driven by a pressure response of highly saline water from Gunnison Bay flowing into the north basin of Gilbert Bay. Short-term flow reversal events measured at the railroad causeway breach have the ability to move measurable amounts of salt and Hg from Gunnison Bay into the DBL. Future disturbance to the steady state conditions currently imposed by the railroad causeway infrastructure could result in changes to the existing chemical balance between Gunnison and Gilbert Bays. Monitoring instruments were installed at six additional sites in the DBL during October 2012 to assess impacts from any future modifications to the railroad causeway.

  12. West Nile Virus transmission in winter: the 2013 Great Salt Lake Bald Eagle and Eared Grebes Mortality event

    Science.gov (United States)

    Ip, Hon S.; Van Wettere, Arnaud J.; McFarlan, Leslie; Shearn-Bochsler, Valerie I.; Dickson, Sammie L.; Baker, JoDee; Hatch, Gary; Cavender, Kimberly; Long, Renee Romaine; Bodenstein, Barbara L.

    2014-01-01

    West Nile Virus (WNV) infection has been reported in over 300 species of birds and mammals. Raptors such as eagles, hawks and falcons are remarkably susceptible, but reports of WNV infection in Bald Eagles (Haliaeetus leucocephalus) are rare and reports of WNV infection in grebes (Podicipediformes) even rarer. We report an unusually large wild bird mortality event involving between 15,000-20,000 Eared Grebes (Podiceps nigricollis) and over 40 Bald Eagles around the Great Salt Lake, Utah, in November-December 2013. Mortality in grebes was first reported in early November during a period when the area was unseasonably warm and the grebes were beginning to gather and stage prior to migration. Ten out of ten Eared Grebes collected during this period were WNV RT-PCR and/or isolation positive. This is the first report of WNV infection in Eared Grebes and the associated mortality event is matched in scale only by the combined outbreaks in American White Pelican (Pelecanus erythrorhynchos) colonies in the north central states in 2002-2003. We cannot be sure that all of the grebes were infected by mosquito transmission; some may have become infected through contact with WNV shed orally or cloacally from other infected grebes. Beginning in early December, Bald Eagles in the Great Salt Lake area were observed to display neurological signs such as body tremors, limb paralysis and lethargy. At least 43 Bald Eagles had died by the end of the month. Nine of nine Bald Eagles examined were infected with WNV. To the best of our knowledge, this is the largest single raptor mortality event since WNV became endemic in the USA. Because the majority of the eagles affected were found after onset of below-freezing temperatures, we suggest at least some of the Bald Eagles were infected with WNV via consumption of infected Eared Grebes or horizontal transmission at roost sites.

  13. Limnological studies on the Pretoria Salt Pan, a hypersaline maar lake

    CSIR Research Space (South Africa)

    Ashton, PJ

    1983-01-01

    Full Text Available The Pretoria Salt pan is shallow and alkaline with pronounced mesothermy at a depth of between 0.55 and 0.7 metres. Secchi disc transparencies ranged from 7 to 19 cm. Endorheic or closed drainage basins are widely distributed in many climate...

  14. Patterns and determinants of halophilic archaea (class halobacteria) diversity in tunisian endorheic salt lakes and sebkhet systems.

    Science.gov (United States)

    Najjari, Afef; Elshahed, Mostafa S; Cherif, Ameur; Youssef, Noha H

    2015-07-01

    We examined the diversity and community structure of members of the halophilic Archaea (class Halobacteria) in samples from central and southern Tunisian endorheic salt lakes and sebkhet (also known as sebkha) systems using targeted 16S rRNA gene diversity survey and quantitative PCR (qPCR) approaches. Twenty-three different samples from four distinct locations exhibiting a wide range of salinities (2% to 37%) and physical characteristics (water, salt crust, sediment, and biofilm) were examined. A total of 4,759 operational taxonomic units at the 0.03 (species-level) cutoff (OTU0.03s) belonging to 45 currently recognized genera were identified, with 8 to 43 genera (average, 30) identified per sample. In spite of the large number of genera detected per sample, only a limited number (i.e., 2 to 16) usually constituted the majority (≥80%) of encountered sequences. Halobacteria diversity showed a strong negative correlation to salinity (Pearson correlation coefficient = -0.92), and community structure analysis identified salinity, rather than the location or physical characteristics of the sample, as the most important factor shaping the Halobacteria community structure. The relative abundance of genera capable of biosynthesis of the compatible solute(s) trehalose or 2-sulfotrehalose decreased with increasing salinities (Pearson correlation coefficient = -0.80). Indeed, qPCR analysis demonstrated that the Halobacteria otsB (trehalose-6-phosphatase)/16S rRNA gene ratio decreases with increasing salinities (Pearson correlation coefficient = -0.87). The results highlight patterns and determinants of Halobacteria diversity at a previously unexplored ecosystem and indicate that genera lacking trehalose biosynthetic capabilities are more adapted to growth in and colonization of hypersaline (>25% salt) ecosystems than trehalose producers. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  15. The fate of minor alkali elements in the chemical evolution of salt lakes

    Science.gov (United States)

    2011-01-01

    Alkaline earth elements and alkali metals (Mg, Ca, Na and K) play an important role in the geochemical evolution of saline lakes as the final brine type is defined by the abundance of these elements. The role of major ions in brine evolution has been studied in great detail, but little has been done to investigate the behaviour of minor alkali elements in these systems despite their similar chemical affinities to the major cations. We have examined three major anionic brine types, chloride, sulphate, and bicarbonate-carbonate, in fifteen lakes in North America and Antarctica to determine the geochemical behaviour of lithium, rubidium, strontium, and barium. Lithium and rubidium are largely conservative in all water types, and their concentrations are the result of long-term solute input and concentration through evaporation and/or sublimation. Strontium and barium behaviours vary with anionic brine type. Strontium can be removed in sulphate and carbonate-rich lakes by the precipitation of carbonate minerals. Barium may be removed in chloride and sulphate brines by either the precipitation of barite and perhaps biological uptake. PMID:21992434

  16. Piroplasmids of livestock in Tunisia.

    Science.gov (United States)

    Darghouth, M A

    2004-01-01

    Several species of piroplasms of livestock are present in Tunisia; some of them are of high veterinary importance. This paper reviews the species already reported in Tunisia on the basis of clinical observations, parasitological routine diagnostic and serological surveys, as well as those considered as potentially present according to epidemiological argumentations. The genus Theileria includes four species reported in Tunisia: T. annulata, T. buffeli, T. ovis, and T. equi. The ovine malignant theileriosis agent, T. lestoquardi, appears to be absent in Tunisia. Five species belonging to the genus Babesia were reported in the country, namely B. hovis, B. bigemina, B. divergens, B. caballi, and B. ovis. Furthermore, two more species, B. major and B. motasi, are potentially present in zones where their vectors of the genus Haemaphysalis occur.

  17. Sport and Identity in Tunisia

    National Research Council Canada - National Science Library

    Sato, Daisuke

    2005-01-01

    Under the rule of the Cheikhs, before Tunisia became a French colony, such traditional sports as El Koura and El'Efga took place at the village community level, but after the introduction of modern...

  18. Republic of Tunisia.

    Science.gov (United States)

    Newcomb, L

    1986-01-01

    The north African country of Tunisia (632,387 square miles) consists largely of desert, with some rich farmlands and a rocky transitional zone. Despite the government's family planning efforts, the population grew from 5.6 million in 1975, to 7.2 million in 1985, and, with its 2.4% annual growth rate, is projected to reach 8.1 million by 1990. Tunisia's rural population decreased to 46% in 1985 as workers and their families moved into urban areas. 98% of the population is Arab-Berber; Arabic and French are the offical languages. The age-sex distribution is typical of developing countries; the median age has increased from 16.8 years in 1966 to 19.5 in 1950 and persons over age 60 have increased from 5.1% in 1956 to 6.7% in 1980. Tunisian families average 5.7 persons in rural areas, and 5.4 persons in urban one. Marriages are declining, polygamy is outlawed, and divorce, once easy, is more difficult and declining. At independence in 1956, only 15% of Tunisians were literate, now 85-90% of primary school age children are enrolled and literacy had risen to 53% in 1980. Women, once heavily veiled, now have full rights and access to education. More than 60 thousand new workers compete for the 40,000 new job openings each year. An estimated 7000 laborers found work in Europe in 1984. Women composed only 11% of the 1975 work force, but by 1980, held 20% of jobs, although they were mainly low paying positions. In 1980, 35% of the laborers worked in agriculture, 19% in industry, 17% in service industries, and 10% in construction. Agriculture and tourism have declined in recent years, contributing to social unrest, currency decline, and inflated wages and consumer prices.

  19. A theoretical study of a direct contact membrane distillation system coupled to a salt-gradient solar pond for terminal lakes reclamation.

    Science.gov (United States)

    Suárez, Francisco; Tyler, Scott W; Childress, Amy E

    2010-08-01

    Terminal lakes are water bodies that are located in closed watersheds with the only output of water occurring through evaporation or infiltration. The majority of these lakes, which are commonly located in the desert and influenced by human activities, are increasing in salinity. Treatment options are limited, due to energy costs, and many of these lakes provide an excellent opportunity to test solar-powered desalination systems. This paper theoretically investigates utilization of direct contact membrane distillation (DCMD) coupled to a salt-gradient solar pond (SGSP) for sustainable freshwater production at terminal lakes. A model for heat and mass transport in the DCMD module and a thermal model for an SGSP were developed and coupled to evaluate the feasibility of freshwater production. The construction of an SGSP outside and inside of a terminal lake was studied. As results showed that freshwater flows are on the same order of magnitude as evaporation, these systems will only be successful if the SGSP is constructed inside the terminal lake so that there is little or no net increase in surface area. For the study site of this investigation, water production on the order of 2.7 x 10(-3) m(3) d(-1) per m(2) of SGSP is possible. The major advantages of this system are that renewable thermal energy is used so that little electrical energy is required, the coupled system requires low maintenance, and the terminal lake provides a source of salts to create the stratification in the SGSP. (c) 2010 Elsevier Ltd. All rights reserved.

  20. Neotectonic deformation in Tunisia (North of the African plate)

    Science.gov (United States)

    Soumaya, Abdelkader; Ben Ayed, Noureddine; Kadri, Ali; Delvaux, Damien; Khayati Ammar, Hayet; Braham, Ahmed

    2017-04-01

    In Tunisia, at the extreme North of the African plate, the neotectonic context is largely influenced by the Eurasia-Africa convergence. The aim of this work is to characterize the neotectonic regime that affected this region during Quaternary. Field work investigations integrated with published data allowed to evidence a spatial-temporal variation of the tectonic stress regime during this period. The spatial repartition of the different types of Quaternary to historical deformation shows a North-South neotectonic zoning in Tunisia. After lower Pleistocene, the Tellian domain (Maghrebides) in the North and its Atlassic foreland in central Tunisia are affected by NNW-SSE compression. It generated E-W to NE-SW folds and reverse faults, well developed in the Plio-Quaternary molassic basins of Kechabta and Jendouba (Northern Tunisia). In the Atlas, the major E-W and N-S pre-existing faults have been reactivated with dextral and sinistral strike-slip kinematic respectively, associated to en-echelon folds (Kasserine, N-S Axis, Northern Chott belt...). After the Tyrrhenian, a submeridian compressional regime affected Northern Tunisia (e.g., Bizerte region) and was responsible for the E-W folding of marine strata. More to the South, in the Tunisian Sahel, transtensional tectonics with a NW-SE horizontal maximal compression (SHmax) deformed the Tyrrhenian marine series (Khénis, Skanès, Monastir…). During the Holocene and up to present-day times, N-S compressional tectonics reactivated the E-W pre-existing faults with a reverse movement in Northern Tunisia (Bulla Regia, Utica …), generating historical earthquakes. In Central Tunisia, the Aqueduct of Cherichira (built around AD 850) is displaced by a N-S normal fault. Similarly, a mosaic of a roman house is shifted by 10 cm, along a N-S sinistral normal fault. These deformations evidence a transtensional tectonic regime. During the Quaternary, all the NW-SE oriented grabens are subsiding (e.g., Bizerte Lake, Grombalia

  1. Potential for water borne and invertebrate transmission of West Nile virus in the Great Salt Lake, Utah

    Science.gov (United States)

    Lund, Melissa; Shearn-Bochsler, Valerie I.; Dusek, Robert; Shivers, Jan; Hofmeister, Erik K.

    2017-01-01

    In November and December of 2013, a large mortality event involving 15,000 - 20,000 eared grebes (Podiceps nigricollis) occurred at the Great Salt Lake (GSL), UT. The onset of the outbreak in grebes was followed by a mortality event in > 86 bald eagles (Haliaeetus leucocephalus). During the die-off, West Nile virus (WNV) was detected by RT-PCR or viral culture in carcasses of grebes and eagles submitted to the National Wildlife Health Center. However, no mosquito activity, the primary vector of WNV, was detected by the State of Utah's WNV monitoring program. Transmission of WNV has rarely been reported during the winter in North America in the absence of known mosquito activity; however, the size of this die-off, the habitat in which it occurred, and the species involved are unique. We experimentally investigated whether WNV could survive in water with a high saline content, as found at the GSL, and whether brine shrimp, the primary food of migrating eared grebes on the GSL, could have played a role in transmission of WNV to feeding birds. We found that WNV can survive up to 72 h at 4°C in water containing 30 — 150 ppt NaCl and brine shrimp, incubated with WNV in 30 ppt NaCl, may adsorb WNV to their cuticle and, through feeding, may infect epithelial cells of their gut. Both mechanisms may have potentiated the WNV die-off in migrating eared grebes on the GSL.

  2. Enrichment of arsenic transforming and resistant heterotrophic bacteria from sediments of two salt lakes in Northern Chile.

    Science.gov (United States)

    Lara, José; Escudero González, Lorena; Ferrero, Marcela; Chong Díaz, Guillermo; Pedrós-Alió, Carlos; Demergasso, Cecilia

    2012-05-01

    Microbial populations are involved in the arsenic biogeochemical cycle in catalyzing arsenic transformations and playing indirect roles. To investigate which ecotypes among the diverse microbial communities could have a role in cycling arsenic in salt lakes in Northern Chile and to obtain clues to facilitate their isolation in pure culture, sediment samples from Salar de Ascotán and Salar de Atacama were cultured in diluted LB medium amended with NaCl and arsenic, at different incubation conditions. The samples and the cultures were analyzed by nucleic acid extraction, fingerprinting analysis, and sequencing. Microbial reduction of As was evidenced in all the enrichments carried out in anaerobiosis. The results revealed that the incubation factors were more important for determining the microbial community structure than arsenic species and concentrations. The predominant microorganisms in enrichments from both sediments belonged to the Firmicutes and Proteobacteria phyla, but most of the bacterial ecotypes were confined to only one system. The occurrence of an active arsenic biogeochemical cycle was suggested in the system with the highest arsenic content that included populations compatible with microorganisms able to transform arsenic for energy conservation, accumulate arsenic, produce H(2), H(2)S and acetic acid (potential sources of electrons for arsenic reduction) and tolerate high arsenic levels.

  3. Natronospira proteinivora gen. nov., sp. nov, an extremely salt-tolerant, alkaliphilic gammaproteobacterium from hypersaline soda lakes.

    Science.gov (United States)

    Sorokin, Dimitry Y; Kublanov, Ilya V; Khijniak, Tatiana V

    2017-08-01

    Brine samples from Kulunda Steppe soda lakes (Altai, Russia) were inoculated into a hypersaline alkaline mineral medium with β-keratin (chicken feather) as a substrate. The micro-organisms dominating the enrichment culture were isolated by limiting serial dilution on the same medium with casein as a substrate. The cells of strain BSker1T were motile, curved rods. The strain was an obligately aerobic heterotroph utilizing proteins and peptides as growth substrates. The isolate was an obligate alkaliphile with a pH range for growth from pH 8.5 to 10.25 (optimum at pH 9.5), and it was extremely salt tolerant, growing with between 1 and 4.5 M total Na+ (optimally at 2-2.5 M). BSker1T had a unique composition of polar lipid fatty acids, dominated by two C17 species. The membrane polar lipids included multiple unidentified phospholipids and two aminolipids. According to phylogenetic analysis of the 16S rRNA gene sequence, the isolate forms a novel branch within the family Ectothiorhodospiraceae (class Gammaproteobacteria) with the highest sequence similarity to the members of this family being 91 %. On the basis of distinct phenotypic and genotypic properties, strain BSker1T (=JCM 31341T=UNIQEM U1008T) is proposed to be classified as a representative of a novel genus and species, Natronospira proteinivora gen. nov., sp. nov.

  4. Terminal Pleistocene to early Holocene volcanic eruptions at Zuni Salt Lake, west-central New Mexico, USA

    Science.gov (United States)

    Onken, Jill; Forman, Steven

    2017-01-01

    Zuni Salt Lake (ZSL) is a large maar in the Red Hill-Quemado volcanic field located in west-central New Mexico in the southwestern USA. Stratigraphic analysis of sections in and around the maar, coupled with optically stimulated luminescence (OSL) and accelerator mass spectrometry (AMS) 14C dating, indicate that ZSL volcanic activity occurred between ˜13.4 and 9.9 ka and was most likely confined to a ≤500-year interval sometime between ˜12.3 and 11.0 ka. The basal volcanic unit consists of locally widespread basaltic ash fallout interpreted to represent a violent or wind-aided strombolian eruption tentatively attributed to Cerro Pomo, a scoria cone ˜10 km south of ZSL. Subsequent eruptions emanated from vents near or within the present-day ZSL maar crater. Strombolian eruptions of multiple spatter and scoria cones produced basaltic lava and scoria lapilli fallout. Next, a phreatomagmatic eruption created the maar crater and surrounding tephra rim and apron. ZSL eruptions ended with strombolian eruptions that formed three scoria cones on the crater floor. The revised age range of ZSL is younger and more precise than the 190-24 ka 2-sigma age range derived from previous argon dating. This implies that other morphologically youthful, argon-dated volcanoes on the southern margin of the Colorado Plateau might be substantially younger than previously reported.

  5. Numerical Simulations of an Inversion Fog Event in the Salt Lake Valley during the MATERHORN-Fog Field Campaign

    Science.gov (United States)

    Chachere, Catherine N.; Pu, Zhaoxia

    2018-01-01

    An advanced research version of the Weather Research and Forecasting (WRF) Model is employed to simulate a wintertime inversion fog event in the Salt Lake Valley during the Mountain Terrain Atmospheric Modeling and Observations Program (MATERHORN) field campaign during January 2015. Simulation results are compared to observations obtained from the field program. The sensitivity of numerical simulations to available cloud microphysical (CM), planetary boundary layer (PBL), radiation, and land surface models (LSMs) is evaluated. The influence of differing visibility algorithms and initialization times on simulation results is also examined. Results indicate that the numerical simulations of the fog event are sensitive to the choice of CM, PBL, radiation, and LSM as well as the visibility algorithm and initialization time. Although the majority of experiments accurately captured the synoptic setup environment, errors were found in most experiments within the boundary layer, specifically a 3° warm bias in simulated surface temperatures compared to observations. Accurate representation of surface and boundary layer variables are vital in correctly predicting fog in the numerical model.

  6. Effects of urbanization on benthic macroinvertebrate assemblages in contrasting environmental settings: Boston, Massachusetts; Birmingham, Alabama; and Salt Lake City, Utah

    Science.gov (United States)

    Cuffney, T.F.; Zappia, H.; Giddings, E.M.P.; Coles, J.F.

    2005-01-01

    Responses of invertebrate assemblages along gradients of urban intensity were examined in three metropolitan areas with contrasting climates and topography (Boston, Massachusetts; Birmingham, Alabama; Salt Lake City, Utah). Urban gradients were defined using an urban intensity index (UII) derived from basin-scale population, infrastructure, land-use, land-cover, and socioeconomic characteristics. Responses based on assemblage metrics, indices of biotic integrity (B-IBI), and ordinations were readily detected in all three urban areas and many responses could be accurately predicted simply using regional UIIs. Responses to UII were linear and did not indicate any initial resistance to urbanization. Richness metrics were better indicators of urbanization than were density metrics. Metrics that were good indicators were specific to each study except for a richness-based tolerance metric (TOLr) and one B-IBI. Tolerances to urbanization were derived for 205 taxa. These tolerances differed among studies and with published tolerance values, but provided similar characterizations of site conditions. Basin-scale land-use changes were the most important variables for explaining invertebrate responses to urbanization. Some chemical and instream physical habitat variables were important in individual studies, but not among studies. Optimizing the study design to detect basin-scale effects may have reduced the ability to detect local-scale effects. ?? 2005 by the American Fisheries Society.

  7. Baseline risk assessment of ground water contamination at the uranium mill tailings site near Salt Lake City, Utah. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    The Uranium Mill Tailings Remedial Action (UMTRA) Project consists of two phases: the first is the Surface Project, and the second is the Ground Water Project. For the UMTRA Project site known as the Vitro site, near Salt Lake City, Utah, Surface Project cleanup occurred from 1985 to 1987. The UMTRA Project`s second phase, the Ground Water Project, evaluates the nature and extent of ground water contamination resulting from uranium processing and determines a strategy for ground water compliance with the Environmental Protection Agency (EPA) ground water standards established for the UMTRA Project. A risk assessment is the process of describing a source of contamination and showing how that contamination may reach people and the environment. The amount of contamination people or the environment may be exposed to is calculated and used to characterize the possible health or environmental effects that may result from this exposure. This risk assessment report is the first site-specific document prepared for the UMTRA Ground Water Project at the Vitro site. The results of this report and further site characterization of the Vitro site will be used to determine what is necessary, if anything, to protect human health and the environment while complying with EPA standards.

  8. Water-quality investigations of the Jordan River, Salt Lake County, Utah, 1980-82

    Science.gov (United States)

    Stephens, D.W.

    1984-01-01

    Water-quality studies were conducted on the Jordan River, Utah, to investigate specific problems: dissolved oxygen, toxic substances, sanitary quality, and turbidity and suspended sediment. The dissolved oxygen decreased from 8 milligrams per liter at the Jordan Narrows to less than 5 milligrams per liter at 500 North Street. Chemical oxygen demand increased about 23 percent and biochemical oxygen demand increased 90 percent. Nearly 78 percent of the water samples analyzed for total mercury exceeded the State intended-use standard of 0.05 microgram per liter. Concentrations of ammonia, cadmium, copper, lead, and zinc exceeded the standards periodically. The pesticides DDD, DDE, DDT, dieldrin, methoxychlor, and 2,4-D were occasionally detected in bottom materials. Most were present in quantities of less than 15 micrograms per kilogram. Concentrations of three indicator bacteria (total coliform, fecal coliform, and fecal streptococcus) increased in a downstream direction. Concentrations of total coliform bacteria often exceeded 5,000 colonies per 100 milliliters and concentrations of fecal coliform bacteria often exceeded 2,000 colonies per 100 milliliters. The primary sources of turbidity in the Jordan River are Utah Lake and discharges from the wastewater-treatment plants. Large values of turbidity were measured at the Jordan Narrows with a summer mean value of 88 nephelometer turbidity units (NTU) and a winter mean value of 43 NTU. (USGS)

  9. Pontibacter aydingkolensis sp. nov., isolated from soil of a salt lake.

    Science.gov (United States)

    Osman, Ghenijan; Zhang, Tao; Lou, Kai; Gao, Yan; Chang, Wei; Lin, Qing; Yang, Hong-Mei; Huo, Xiang-Dong; Wang, Ning

    2016-12-01

    A Gram-stain-negative, short rod-shaped and light-red-pigmented bacterium, designated XAAS-1T, was isolated from the soil of Aydingkol Lake near the Turpan City, Xinjiang, China. The isolate was positive for oxidase, catalase and hydrolysis of starch, casein, gelatin and aesculin. The sole respiratory quinone was MK-7 and the principal cellular fatty acids were iso-C15 : 0 and C15 : 0 3-OH. The major polar lipids were phosphatidylethanolamine, one unidentified phospholipid and two unidentified polar lipids. The polyamine pattern was found to contain mainly sym-homospermidine. 16S rRNA gene sequence analysis indicated that strain XAAS-1T belongs to the genus Pontibacter in the family Cytophagaceae, with sequence similarities ranging from 93.8 to 96.7 % with other type species of the genus Pontibacter. On the basis of phenotypic and genotypic data, strain XAAS-1T represents a novel species of the genus Pontibacter, for which the name Pontibacter aydingkolensis sp. nov. (type strain XAAS-1T=CCTCC AB 2016134T=JCM 31442T) is proposed.

  10. Anthropogenic influences on the input and biogeochemical cycling of nutrients and mercury in Great Salt Lake, Utah, USA

    Science.gov (United States)

    Naftz, D.; Angeroth, C.; Kenney, T.; Waddell, B.; Darnall, N.; Silva, S.; Perschon, C.; Whitehead, J.

    2008-01-01

    Despite the ecological and economic importance of Great Salt Lake (GSL), little is known about the input and biogeochemical cycling of nutrients and trace elements in the lake. In response to increasing public concern regarding anthropogenic inputs to the GSL ecosystem, the US Geological Survey (USGS) and US Fish and Wildlife Service (USFWS) initiated coordinated studies to quantify and evaluate the significance of nutrient and Hg inputs into GSL. A 6??? decrease in ??15N observed in brine shrimp (Artemia franciscana) samples collected from GSL during summer time periods is likely due to the consumption of cyanobacteria produced in freshwater bays entering the lake. Supporting data collected from the outflow of Farmington Bay indicates decreasing trends in ??15N in particulate organic matter (POM) during the mid-summer time period, reflective of increasing proportions of cyanobacteria in algae exported to GSL on a seasonal basis. The C:N molar ratio of POM in outflow from Farmington Bay decreases during the summer period, supportive of the increased activity of N fixation indicated by decreasing ??15N in brine shrimp and POM. Although N fixation is only taking place in the relatively freshwater inflows to GSL, data indicate that influx of fresh water influences large areas of the lake. Separation of GSL into two distinct hydrologic and geochemical systems from the construction of a railroad causeway in the late 1950s has created a persistent and widespread anoxic layer in the southern part of GSL. This anoxic layer, referred to as the deep brine layer (DBL), has high rates of SO42 - reduction, likely increasing the Hg methylation capacity. High concentrations of methyl mercury (CH3Hg) (median concentration = 24 ng/L) were observed in the DBL with a significant proportion (31-60%) of total Hg in the CH3Hg form. Hydroacoustic and sediment-trap evidence indicate that turbulence introduced by internal waves generated during sustained wind events can temporarily mix the

  11. Anthropogenic influences on the input and biogeochemical cycling of nutrients and mercury in Great Salt Lake, Utah, USA

    Energy Technology Data Exchange (ETDEWEB)

    Naftz, David [US Geological Survey, Salt Lake City 84119, UT (United States)], E-mail: dlnaftz@usgs.gov; Angeroth, Cory; Kenney, Terry [US Geological Survey, Salt Lake City 84119, UT (United States); Waddell, Bruce; Darnall, Nathan [US Fish and Wildlife Service, Salt Lake City, UT (United States); Silva, Steven [US Geological Survey, Menlo Park, CA (United States); Perschon, Clay [Utah Division of Wildlife Resources, Salt Lake City, UT (United States); Whitehead, John [Utah Department of Environmental Quality, Salt Lake City, UT (United States)

    2008-06-15

    Despite the ecological and economic importance of Great Salt Lake (GSL), little is known about the input and biogeochemical cycling of nutrients and trace elements in the lake. In response to increasing public concern regarding anthropogenic inputs to the GSL ecosystem, the US Geological Survey (USGS) and US Fish and Wildlife Service (USFWS) initiated coordinated studies to quantify and evaluate the significance of nutrient and Hg inputs into GSL. A 6 per mille decrease in {delta}{sup 15}N observed in brine shrimp (Artemia franciscana) samples collected from GSL during summer time periods is likely due to the consumption of cyanobacteria produced in freshwater bays entering the lake. Supporting data collected from the outflow of Farmington Bay indicates decreasing trends in {delta}{sup 15}N in particulate organic matter (POM) during the mid-summer time period, reflective of increasing proportions of cyanobacteria in algae exported to GSL on a seasonal basis. The C:N molar ratio of POM in outflow from Farmington Bay decreases during the summer period, supportive of the increased activity of N fixation indicated by decreasing {delta}{sup 15}N in brine shrimp and POM. Although N fixation is only taking place in the relatively freshwater inflows to GSL, data indicate that influx of fresh water influences large areas of the lake. Separation of GSL into two distinct hydrologic and geochemical systems from the construction of a railroad causeway in the late 1950s has created a persistent and widespread anoxic layer in the southern part of GSL. This anoxic layer, referred to as the deep brine layer (DBL), has high rates of SO{sub 4}{sup 2-} reduction, likely increasing the Hg methylation capacity. High concentrations of methyl mercury (CH{sub 3}Hg) (median concentration = 24 ng/L) were observed in the DBL with a significant proportion (31-60%) of total Hg in the CH{sub 3}Hg form. Hydroacoustic and sediment-trap evidence indicate that turbulence introduced by internal waves

  12. Halovarius luteus gen. nov., sp. nov., an extremely halophilic archaeon from a salt lake.

    Science.gov (United States)

    Mehrshad, Maliheh; Amoozegar, Mohammad Ali; Makhdoumi, Ali; Rasooli, Mehrnoosh; Asadi, Basaer; Schumann, Peter; Ventosa, Antonio

    2015-08-01

    An extremely halophilic archaeon, strain DA50T, was isolated from a brine sample of Urmia lake, a hypersaline environment in north-west Iran. Strain DA50T was orange-pigmented, motile, pleomorphic and required at least 2.5 M NaCl but not MgCl2 for growth. Optimal growth was achieved at 4.0 M NaCl and 0.3 M MgCl2. The optimum pH and temperature for growth were pH 7.0 and 45 °C, while it was able to grow over a pH range of 6.5-8.0 and a temperature range of 25-50 °C. Analysis of 16S rRNA gene sequences revealed that strain DA50T is a member of the family Halobacteriaceae, showing a low level of similarity with other members of this family. Highest similarities, 94.4, 94.0 and 93.9 %, were obtained with the 16S rRNA gene sequences of the type strains of Natrialba aegyptia, Halobiforma lacisalsi and Halovivax asiaticus, respectively. Polar lipid analyses revealed that strain DA50T contains phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. Four unidentified glycolipids and two minor phospholipids were also observed. The only quinone present was MK-8(II-H2). The G+C content of its DNA was 62.3 mol%. On the basis of the data obtained, the new isolate could not be classified in any recognized genus. Strain DA50T is thus considered to represent a novel species of a new genus within the family Halobacteriaceae, order Halobacteriales, for which the name Halovarius luteus gen. nov., sp. nov. is proposed. The type strain of Halovarius luteus is DA50T ( = IBRC-M 10912T = CECT 8510T).

  13. Oceanobacillus longus sp. nov., a moderately halophilic bacterium isolated from a salt lake.

    Science.gov (United States)

    Amoozegar, Mohammad Ali; Bagheri, Maryam; Makhdoumi, Ali; Mehrshad, Maliheh; Didari, Maryam; Schumann, Peter; Spröer, Cathrin; Sánchez-Porro, Cristina; Ventosa, Antonio

    2016-10-01

    A Gram-stain-positive, endospore-forming, long rod-shaped, strictly aerobic, moderately halophilic bacterium, designated strain T9BT, was isolated from a brine sample of the hypersaline lake Aran-Bidgol in Iran. Cells of strain T9BT were motile and produced colonies with a brown pigment. Growth occurred between 1.0 and 20 % (w/v) NaCl and the isolate grew optimally at 5.0 % (v/w) NaCl. The optimum pH and temperature for growth of the strain were pH 7.0 and 35 °C, while it was able to grow over pH and temperature ranges of pH 6.0-9.0 and 25-45 °C. Phylogenetic analysis based on the comparison of 16S rRNA gene sequences revealed that strain T9BT is a member of the genus Oceanobacillus. The closest relative to this strain was Oceanobacillus rekensis PT-11T with a similarity of 97.4 %, followed by Oceanobacillus profundus CL-MP28T and Oceanobacillus polygoni SA9T with 97.3 and 97.1 % similarity, respectively. The major cellular fatty acids of the isolate were anteiso-C15 : 0, iso-C14 : 0 and iso-C16 : 0. The polar lipids of strain T9BT consisted of phosphatidylglycerol, diphosphatidylglycerol, three phospholipids and one aminoglycolipid. It contained MK-7 as the predominant menaquinone and meso-diaminopimelic acid in the cell-wall peptidoglycan. The G+C content of the genomic DNA of this strain was 42.9 mol%. Phylogenetic analysis, DNA-DNA hybridization data and phenotypic characteristics allowed strain T9BT to be differentiated from other members of the genus Oceanobacillus. A novel species, Oceanobacillus longus sp. nov., is therefore proposed to accommodate this strain. The type strain is T9BT (=IBRC-M 10703T=LMG 29250T).

  14. Oceanobacillus limi sp. nov., a moderately halophilic bacterium from a salt lake.

    Science.gov (United States)

    Amoozegar, Mohammad Ali; Bagheri, Maryam; Makhdoumi-Kakhki, Ali; Didari, Maryam; Schumann, Peter; Spröer, Cathrin; Sánchez-Porro, Cristina; Ventosa, Antonio

    2014-04-01

    A Gram-stain-positive, endospore-forming, rod-shaped, strictly aerobic, moderately halophilic bacterium, designated strain H9B(T), was isolated from a mud sample of the hypersaline lake Aran-Bidgol in Iran. Cells of strain H9B(T) were motile and produced colonies with a yellowish-grey pigment. Growth occurred between 2.5 and 10 % (w/v) NaCl and the isolate grew optimally at 7.5 % (w/v) NaCl. The optimum pH and temperature for growth of the strain were pH 7.0 and 35 °C, respectively, while it was able to grow over pH and temperature ranges of pH 6-10 and 25-45 °C, respectively. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain H9B(T) is a member of the genus Oceanobacillus. The closest relative to this strain was Oceanobacillus profundus CL-MP28(T) with 97.1 % 16S rRNA gene sequences similarity. The level of DNA-DNA relatedness between the novel isolate and this phylogenetically related species was 17 %. The major cellular fatty acids of the isolate were anteiso-C15 : 0, anteiso-C17 : 0, iso-C15 : 0 and iso-C16 : 0. The polar lipid pattern of strain H9B(T) consisted of phosphatidylglycerol, diphosphatidylglycerol, four phospholipids and an aminolipid. It contained MK-7 as the predominant menaquinone and meso-diaminopimelic acid in the cell-wall peptidoglycan. The G+C content of the genomic DNA of this strain was 37.1 mol%. Phenotypic characteristics, phylogenetic analysis and DNA-DNA relatedness data suggest that this strain represents a novel species of the genus Oceanobacillus, for which the name Oceanobacillus limi sp. nov. is proposed. The type strain of Oceanobacillus limi is strain H9B(T) ( = IBRC-M 10780(T) = KCTC 13823(T) = CECT 7997(T)).

  15. Halorientalis persicus sp. nov., an extremely halophilic archaeon isolated from a salt lake and emended description of the genus Halorientalis.

    Science.gov (United States)

    Amoozegar, Mohammad Ali; Makhdoumi-Kakhki, Ali; Mehrshad, Maliheh; Fazeli, Seyed Abolhassan Shahzadeh; Spröer, Cathrin; Ventosa, Antonio

    2014-03-01

    An extremely halophilic archaeon, strain D108(T), was isolated from a brine sample of Aran-Bidgol salt lake in Iran. The novel strain was cream-pigmented, motile, pleomorphic rod-shaped and required at least 2.5 M NaCl but not MgCl2 for growth. Optimal growth was achieved with 4.3 M NaCl and 0.1 M MgCl2. The optimum pH and temperature for growth were pH 7.5 and 40 °C, respectively, and the strain was able to grow over a pH range of 6.5 to 9.0, and a temperature range of 30 to 50 °C. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that strain D108(T) clustered with the type strain of the sole species of the genus Halorientalis, Halorientalis regularis TNN28(T), with a sequence similarity of 98.8 %. The polar lipid pattern of strain D108(T) consisted of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, one phosphoglycolipid and two glycolipids. The only quinone present was MK-8(II-H2). The DNA G+C content of strain D108(T) was 62.8 mol%. DNA-DNA hybridization studies (45 % with Halorientalis regularis IBRC-M 10760(T)), as well as biochemical and physiological characterization, allowed strain D108(T) to be differentiated from Halorientalis regularis. A novel species of the genus Halorientalis, Halorientalis persicus sp. nov., is therefore proposed to accommodate this strain. The type strain is D108(T) ( = IBRC-M 10043(T) = CECT 8375(T)). An emended description of the genus Halorientalis is also proposed.

  16. Virgibacillus albus sp. nov., a novel moderately halophilic bacterium isolated from Lop Nur salt lake in Xinjiang province, China.

    Science.gov (United States)

    Zhang, Yun-Jiao; Zhou, Yu; Ja, Man; Shi, Rong; Chun-Yu, Wei-Xun; Yang, Ling-Ling; Tang, Shu-Kun; Li, Wen-Jun

    2012-11-01

    A Gram-positive, moderately halophilic, strictly aerobic bacterium, designated YIM 93624(T), was isolated from a salt lake in Xinjiang province of China and subjected to a polyphasic taxonomic study. Strain YIM 93624(T) grew at 15-45 °C (optimum 25-30 °C), 1-17% (w/v) NaCl (optimum 5-10 %, w/v) and pH 4.0-9.0 (optimum pH 7.0). The predominant menaquinone was found to be MK-7. The major fatty acids were anteiso-C(15:0) and C(16:0). The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, a glycolipid and two unidentified phospholipids. The cell-wall peptidoglycan contained meso-diaminopimelic acid. The G+C content of the genomic DNA was 37.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 93624(T) was a member of the genus Virgibacillus and exhibited the highest similarity of 97.0 % to Virgibacillus koreensis KCTC 3823(T). However, the level of DNA-DNA relatedness between strain YIM 93624(T) and V. koreensis KCTC 3823(T) was 32.5 %. On the basis of phylogenetic, physiological and chemotaxonomic analysis data, the isolate is concluded to represent a novel species of the genus Virgibacillus, for which the name Virgibacillus albus sp. nov., is proposed, with type strain of YIM 93624(T) (=DSM 23711(T) = JCM 17364(T)).

  17. Bringing Community Colleges to Tunisia

    Science.gov (United States)

    Hagedorn, Linda Serra; Mezghani, Wafa Thabet

    2013-01-01

    The country of Tunisia experienced intense uprisings and massive civil resistance that were termed the Arab Spring of 2010. The riots stemmed from a desire to topple government rulers who were blamed for the high unemployment, poverty, regional inequalities, and general political unrest within the country. In a quest for relief and prosperity,…

  18. Sociologie d’une dispute dans l’arbitrage en patinage artistique : le cas de Salt Lake City

    Directory of Open Access Journals (Sweden)

    Cécile Collinet

    2010-09-01

    Full Text Available Notre travail se penche sur les problèmes d’arbitrage en patinage et danse sur glace en prenant appui sur l’affaire de Salt Lake City (affaire internationale. L’arbitrage en patinage artistique ne peut être soumis à une mesure complètement objective, une part de subjectivité reste importante. Nous montrons que cette caractéristique du patinage est à l’origine des disputes relatives à l’arbitrage. Autrement dit, loin de constituer un effet périphérique, surajouté, à ce sport, les problèmes d’arbitrage sont le résultat normal d’un positionnement ambigu et de la confrontation de principes (Boltanski & Thévenot, 1991 difficilement conciliables ouvrant la brèche à un espace de plainte. Le mode de jugement artistique en patinage s’accorde mal avec les valeurs sportives créant ainsi des discordances débouchant sur de véritables affaires. Enfin, nous envisageons comment s’est construite la clôture de la dispute en insistant sur le fait que ce n’est pas l’objectivité du jugement qui est visée par les modifications (nouveau code qui ont suivi l’affaire, mais l’espace de plainte qui se réduit. Ce travail est fondé sur l’analyse d’articles de presse, de témoignages écrits et d’entretiens. Il se centre sur le point de vue français d’une affaire internationale et mobilise des approches sociologiques issues de la sociologie pragmatique, la sociologie de l’art et la sociologie du sport.Our work looks into the judging issues in ice skating and ice dancing, based on the Salt Lake City scandal (an international scandal. Judging in figure skating cannot be entirely objective as a large part of subjectivity remains inherent to the process. We will demonstrate that the controversy surrounding judging decisions originates in this particular feature of ice skating. In other words, judging issues – far from being an extraneous addition to this sport – are the natural consequence of an ambiguous

  19. 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

  20. Geophysical, geochemical and hydrological analyses of water-resource vulnerability to salinization: case of the Uburu-Okposi salt lakes and environs, southeast Nigeria

    Science.gov (United States)

    Ukpai, S. N.; Okogbue, C. O.

    2017-11-01

    Until this study, the location and depth of the saline units in Uburu-Okposi salt lake areas and environs have been unknown. This study aimed at delineating the saline lithofacies and dispersal configurations to water bodies, using electrical geophysical methods such as constant separation traversing (CST) and vertical electrical sounding (VES). Results showed weathered zones that represent aquifers mostly at the fourth geoelectric layer: between upper layered aquitards and underlying aquitards at depths 30-140 m. Lateral distribution of resistivity variance was defined by the CST, whereas the VES tool, targeted at low-resistivity zones, detected isolated saline units with less than 10 ohm-m at depths generally >78 m. The saline lithofacies were suspected to link freshwater zones via shear zones, which steer saline water towards the salt lakes and influence the vulnerability of groundwater to salinization. The level of salinization was verified by water sampling and analysis, and results showed general alkaline water type with a mean pH of 7.66. Water pollution was indicated: mean total dissolved solids (TDS) 550 mg/l, electrical conductivity (EC) 510 μS/cm, salinity 1.1‰, Cl- 200 mg/l, N03 -35.5 mg/l, Na+ 19.6 mg/l and Ca2+ 79.3 mg/l. The salinity is controlled by NaCl salt, as deduced from correlation analysis using the software package Statistical Product for Service Solutions (SPSS). Generally, concentrations of dissolved ions in the water of the area are enhanced via mechanisms such as evaporation, dissociation of salts, precipitation run off and leaching of dissolved rock minerals.

  1. Geophysical, geochemical and hydrological analyses of water-resource vulnerability to salinization: case of the Uburu-Okposi salt lakes and environs, southeast Nigeria

    Science.gov (United States)

    Ukpai, S. N.; Okogbue, C. O.

    2017-06-01

    Until this study, the location and depth of the saline units in Uburu-Okposi salt lake areas and environs have been unknown. This study aimed at delineating the saline lithofacies and dispersal configurations to water bodies, using electrical geophysical methods such as constant separation traversing (CST) and vertical electrical sounding (VES). Results showed weathered zones that represent aquifers mostly at the fourth geoelectric layer: between upper layered aquitards and underlying aquitards at depths 30-140 m. Lateral distribution of resistivity variance was defined by the CST, whereas the VES tool, targeted at low-resistivity zones, detected isolated saline units with less than 10 ohm-m at depths generally >78 m. The saline lithofacies were suspected to link freshwater zones via shear zones, which steer saline water towards the salt lakes and influence the vulnerability of groundwater to salinization. The level of salinization was verified by water sampling and analysis, and results showed general alkaline water type with a mean pH of 7.66. Water pollution was indicated: mean total dissolved solids (TDS) 550 mg/l, electrical conductivity (EC) 510 μS/cm, salinity 1.1‰, Cl- 200 mg/l, N03 -35.5 mg/l, Na+ 19.6 mg/l and Ca2+ 79.3 mg/l. The salinity is controlled by NaCl salt, as deduced from correlation analysis using the software package Statistical Product for Service Solutions (SPSS). Generally, concentrations of dissolved ions in the water of the area are enhanced via mechanisms such as evaporation, dissociation of salts, precipitation run off and leaching of dissolved rock minerals.

  2. Spillovers From Europe Into Morocco and Tunisia

    OpenAIRE

    Daniel Florea; Joël Toujas-Bernate; Reinout De Bock

    2010-01-01

    This paper examines the economic and financial linkages between Morocco and Tunisia and their European partners. Using structural vector autoregressions, we find that growth shocks in European partner countries generate significant responses on growth in Morocco and Tunisia. For Tunisia, exports and, to a much lesser extent, tourism appear to be the major transmission channels. In Morocco, exports, remittances and tourism play relatively equal roles. An analysis with sectoral data supports th...

  3. A novel cold-adapted and highly salt-tolerant esterase from Alkalibacterium sp. SL3 from the sediment of a soda lake.

    Science.gov (United States)

    Wang, Guozeng; Wang, Qiaohuang; Lin, Xianju; Ng, Tzi Bun; Yan, Renxiang; Lin, Juan; Ye, Xiuyun

    2016-02-26

    A novel esterase gene (estSL3) was cloned from the Alkalibacterium sp. SL3, which was isolated from the sediment of soda lake Dabusu. The 636-bp full-length gene encodes a polypeptide of 211 amino acid residues that is closely related with putative GDSL family lipases from Alkalibacterium and Enterococcus. The gene was successfully expressed in E. coli, and the recombinant protein (rEstSL3) was purified to electrophoretic homogeneity and characterized. rEstSL3 exhibited the highest activity towards pNP-acetate and had no activity towards pNP-esters with acyl chains longer than C8. The enzyme was highly cold-adapted, showing an apparent temperature optimum of 30 °C and remaining approximately 70% of the activity at 0 °C. It was active and stable over the pH range from 7 to 10, and highly salt-tolerant up to 5 M NaCl. Moreover, rEstSL3 was strongly resistant to most tested metal ions, chemical reagents, detergents and organic solvents. Amino acid composition analysis indicated that EstSL3 had fewer proline residues, hydrogen bonds and salt bridges than mesophilic and thermophilic counterparts, but more acidic amino acids and less hydrophobic amino acids when compared with other salt-tolerant esterases. The cold active, salt-tolerant and chemical-resistant properties make it a promising enzyme for basic research and industrial applications.

  4. Metagenome cloning and functional analysis of Na⁺/H⁺ antiporter genes from Keke Salt Lake in China.

    Science.gov (United States)

    Gao, Maio; Wang, Lei; Chen, San-Feng

    2012-02-01

    Na⁺/H⁺ antiporters are ubiquitous membrane proteins and play a central role in cell homeostasis including pH regulation, osmoregulation, and Na⁺/Li⁺ tolerance in bacteria. The microbial communities in extremely hypersaline soil are an important resource for isolating Na⁺/H⁺ antiporter genes. A metagenomic library containing 35,700 clones was constructed by using genomic DNA obtained from the hypersaline soil samples of Keke Salt Lake in Northwest of China. Two Na⁺/H⁺ antiporters, K1-NhaD, and K2-NhaD belonging to NhaD family, were screened and cloned from this metagenome by complementing the triple mutant Escherichia coli strain KNabc (nhaA⁻, nhaB⁻, chaA⁻) in medium containing 0.2 M NaCl. K1-NhaD and K2-NhaD have 75.5% identity at the predicted amino acid sequence. K1-NhaD has 78% identity with Na⁺/H⁺ antiporter NhaD from Halomonas elongate at the predicted amino acid sequence. The predicted K1-NhaD is a 53.5 kDa protein (487 amino acids) with 13 transmembrane helices. K2-NhaD has 73% identity with Alkalimonas amylolytica NhaD. The predicted K2-NhaD is a 55 kDa protein (495 amino acids) with 12 transmembrane helices. Both K1-NhaD and K2-NhaD could make the triple mutant E. coli KNabc (nhaA⁻, nhaB⁻, chaA⁻) grow in the LBK medium containing 0.2-0.6 M Na⁺ or with 0.05-0.4 M Li⁺. Everted membrane vesicles prepared from E. coli KNabc cells carrying K1-NhaD or K2-NhaD exhibited Na⁺/H⁺ and Li⁺/H⁺ antiporter activities which were pH-dependent with the highest activity at pH 9.5. Little K⁺/H⁺ antiporter activity was also detected in vesicles form E. coli KNabc carrying K1-NhaD or K2-NhaD.

  5. Halomonas qijiaojingensis sp. nov. and Halomonas flava sp. nov., two moderately halophilic bacteria isolated from a salt lake.

    Science.gov (United States)

    Chen, Chao; Shi, Rong; Liu, Bing-Bing; Zhang, Yun-Jiao; Sun, Hong-Zhuan; Li, Chang-Tian; Tang, Shu-Kun; Zhang, Li-Li; Li, Wen-Jun

    2011-10-01

    Two moderately halophilic, Gram-negative, rod-shaped bacteria, designated YIM 93003(T) and YIM 94343(T), were isolated from a salt lake in Xinjiang province, north-west China. The two strains YIM 93003(T) and YIM 94343(T) grew at 20-40°C, pH 6-9, 0.5-24% (w/v) NaCl and at 20-40°C, pH 6-9, 0.5-23% (w/v) NaCl, respectively. No growth occurred in absence of NaCl. Phylogenetic analyses based on 16S rRNA gene sequences showed that strains YIM 93003(T) and YIM 94343(T) were phylogenetically affiliated to the genus Halomonas and exhibited sequence similarity of 97.5% and 97.4% to the type strain Halomonas anticariensis DSM 16096(T), respectively. The strains possessed chemotaxonomic markers that were consistent with their classification in the genus Halomonas (Q-9 as predominant respiratory quinine; C18:1ω7c, C16:0 and C16:1 ω7c/iso-C15:02-OH as the major fatty acids). The DNA-DNA hybridization values for strains YIM 93003(T) and YIM 94343(T), YIM 93003(T) and DSM 16096(T), YIM 94343(T) and DSM 16096(T) were 38.1 ± 3.0, 18.3 ± 4.7, and 20.8 ± 4.6%, respectively. The G+C contents of the strains YIM 93003(T) and YIM 94343(T) were 63.4 and 64.0 mol%, respectively. Based on comparative analysis of physiological, biochemical and chemotaxonomic data, including low DNA-DNA hybridization results, two novel species, Halomonas qijiaojingensis sp. nov., and Halomonas flava sp. nov., are proposed. The type strains are YIM 93003(T) (=CCTCC AB 208133(T) =KCTC 22228(T)) and YIM 94343(T) (=CCTCC AB 2010382(T) =KCTC 23356(T)), respectively.

  6. Decadal-scale changes in dissolved-solids concentrations in groundwater used for public supply, Salt Lake Valley, Utah

    Science.gov (United States)

    Thiros, Susan A.; Spangler, Larry

    2010-01-01

    Basin-fill aquifers are a major source of good-quality water for public supply in many areas of the southwestern United States and have undergone increasing development as populations have grown over time. During 2005, the basin-fill aquifer in Salt Lake Valley, Utah, provided approximately 75,000 acre-feet, or about 29 percent of the total amount of water used by a population of 967,000. Groundwater in the unconsolidated basin-fill deposits that make up the aquifer occurs under unconfined and confined conditions. Water in the shallow unconfined part of the groundwater system is susceptible to near-surface contamination and generally is not used as a source of drinking water. Groundwater for public supply is withdrawn from the deeper unconfined and confined parts of the system, termed the principal aquifer, because yields generally are greater and water quality is better (including lower dissolved-solids concentrations) than in the shallower parts of the system. Much of the water in the principal aquifer is derived from recharge in the adjacent Wasatch Range (mountain-block recharge). In many areas, the principal aquifer is separated from the overlying shallow aquifer by confining layers of less permeable, fine-grained sediment that inhibit the downward movement of water and any potential contaminants from the surface. Nonetheless, under certain hydrologic conditions, human-related activities can increase dissolved-solids concentrations in the principal aquifer and result in groundwater becoming unsuitable for consumption without treatment or mixing with water having lower dissolved-solids concentrations. Dissolved-solids concentrations in areas of the principal aquifer used for public supply typically are less than 500 milligrams per liter (mg/L), the U.S. Environmental Protection Agency (EPA) secondary (nonenforceable) drinking-water standard. However, substantial increases in dissolved-solids concentrations in the principal aquifer have been documented in some

  7. Spatial analysis of groundwater electrical conductivity using ordinary kriging and artificial intelligence methods (Case study: Maharlu-Bakhtegan and Tashk salt lakes basin, Iran)

    Science.gov (United States)

    Ghader, Fatemeh; Aljoumani, Basem; Tröger, Uwe

    2017-04-01

    The main resources of fresh water are the groundwater. In Iran, the quality and quantity of groundwater is affected significantly by rapid population growth and unsustainable water management in the agricultural and industrial sectors. in Maharlu-Bakhtegan and Tashk salt lakes basin, the overexploitation of groundwater for irrigation purpose caused the salt water intrusion from the lakes to the area's aquifers, moreover, the basin is located in south of Iran with semiarid climate, faces a significant decline in rainfall. All these reasons cause the degradation of ground water quality. For this study, geographical coordinates of 406 observation wells will be defined as inputs and groundwater electrical conductivities (EC) will be set as output. Ordinary kriging (OK) and artificial neural networks (ANN) will be investigated for modeling groundwater salinity. Eighty percent of data will be randomly selected to train and develop mentioned models and twenty percent of data will be used for testing and validating. Finally, the outputs of models will be compared with the corresponding measured values in observation wells.

  8. Hydrology and water quality of an urban stream reach in the Great Basin - Little Cottonwood Creek near Salt Lake City, Utah, water years 1999-2000

    Science.gov (United States)

    Gerner, Steven J.; Waddell, Kidd M.

    2003-01-01

    The hydrology and water quality of an urbanized reach of Little Cottonwood Creek near Salt Lake City, Utah, were examined as part of the Great Salt Lake Basins study, part of the U.S. Geological Survey National Water-Quality Assessment program. Physical and chemical properties of the stream were referenced to established aquatic-life criteria as available. Two fixed sampling sites were established on Little Cottonwood Creek with the purpose of determining the influence of urbanization on the water quality of the stream. The fixed-site assessment is a component of the National Water-Quality Assessment surface-water study design used to assess the spatial and temporal distribution of selected water-quality constituents.The occurrence and distribution of major ions, nutrients, trace elements, dissolved and suspended organic carbon, pesticides, volatile organic compounds, and suspended sediment were monitored during this study. From October 1998 to September 2000, stream samples were collected at regular intervals at the two fixed sites. Additional samples were collected at these sites during periods of high flow, which included runoff from snowmelt in the headwaters and seasonal thunderstorms in the lower basin.

  9. A Three-Component Microbial Consortium from Deep-Sea Salt-Saturated Anoxic Lake Thetis Links Anaerobic Glycine Betaine Degradation with Methanogenesis

    Directory of Open Access Journals (Sweden)

    Violetta La Cono

    2015-09-01

    Full Text Available Microbial communities inhabiting the deep-sea salt-saturated anoxic lakes of the Eastern Mediterranean operate under harsh physical-chemical conditions that are incompatible with the lifestyle of common marine microorganisms. Here, we investigated a stable three-component microbial consortium obtained from the brine of the recently discovered deep-sea salt-saturated Lake Thetis. The trophic network of this consortium, established at salinities up to 240, relies on fermentative decomposition of common osmoprotectant glycine betaine (GB. Similarly to known extreme halophilic anaerobic GB-degrading enrichments, the initial step of GB degradation starts with its reductive cleavage to trimethylamine and acetate, carried out by the fermenting member of the Thetis enrichment, Halobacteroides lacunaris TB21. In contrast to acetate, which cannot be easily oxidized in salt-saturated anoxic environments, trimethylamine represents an advantageous C1-substrate for methylotrophic methanogenic member of the Thetis enrichment, Methanohalophilus sp. TA21. This second member of the consortium likely produces hydrogen via methylotrophic modification of reductive acetyl-CoA pathway because the initial anaerobic GB cleavage reaction requires the consumption of reducing equivalents. Ecophysiological role of the third member of the Thetis consortium, Halanaerobium sp. TB24, which lacks the capability of either GB or trimethylamine degradation, remains yet to be elucidated. As it is true for cultivated members of family Halanaerobiaceae, the isolate TB24 can obtain energy primarily by fermenting simple sugars and producing hydrogen as one of the end products. Hence, by consuming of TB21 and TA21 metabolites, Halanaerobium sp. TB24 can be an additional provider of reducing equivalents required for reductive degradation of GB. Description of the Thetis GB-degrading consortium indicated that anaerobic degradation of osmoregulatory molecules may play important role in the

  10. Highly-resolved Modeling of Emissions and Concentrations of Carbon Monoxide, Carbon Dioxide, Nitrogen Oxides, and Fine Particulate Matter in Salt Lake City, Utah

    Science.gov (United States)

    Mendoza, D. L.; Lin, J. C.; Mitchell, L.; Ehleringer, J. R.

    2014-12-01

    Accurate, high-resolution data on air pollutant emissions and concentrations are needed to understand human exposures and for both policy and pollutant management purposes. An important step in this process is also quantification of uncertainties. We present a spatially explicit and highly resolved emissions inventory for Salt Lake County, Utah, and trace gas concentration estimates for carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxides (NOx) and fine particles (PM2.5) within Salt Lake City. We assess the validity of this approach by comparing measured concentrations against simulated values derived from combining the emissions inventory with an atmospheric model. The emissions inventory for the criteria pollutants was constructed using the 2011 National Emissions Inventory (NEI). The spatial and temporal allocation methods from the Emission Modeling Clearinghouse data set are used to downscale the NEI data from annual to hourly scales and from county-level to 500 m x 500 m resolution. Onroad mobile source emissions were estimated by combining a bottom-up emissions calculation approach for large roadway links with a top-down spatial allocation approach for other roadways. Vehicle activity data for road links were derived from automatic traffic responder data. The emissions inventory for CO2 was obtained from the Hestia emissions data product at an hourly, building, facility, and road link resolution. The AERMOD and CALPUFF dispersion models were used to transport emissions and estimate air pollutant concentrations at an hourly temporal and 500 m x 500 m spatial resolution. Modeled results were compared against measurements from a mobile lab equipped with trace gas measurement equipment traveling on pre-determined routes in the Salt Lake City area. The comparison between both approaches to concentration estimation highlights spatial locations and hours of high variability/uncertainty. Results presented here will inform understanding of variability and

  11. Conference Proceedings: Seed Ecology III - The Third International Society for Seed Science Meeting on Seeds and the Environment - "Seeds and Change"; June 20-June 24, 2010; Salt Lake City, Utah, USA

    Science.gov (United States)

    Rosemary Pendleton; Susan Meyer; Bitsy Schultz

    2010-01-01

    Seed Ecology III was held in Salt Lake City, Utah in June 2010, sharing the latest research on all aspects of seed ecology. Our meeting was organized around the theme "Seeds and Change." We welcomed contributions in any area of seed ecology. Our agenda also aimed to create bridges between seed ecology and plant conservation, restoration ecology, and global...

  12. An investigation of several aspects of LANDSAT-5 data quality. [Palmer County, Shelby, mt; White sands, NM; Great Salt Lake, UT; San Matted Bridge and Sacramento, California

    Science.gov (United States)

    Wrigley, R. C. (Principal Investigator)

    1984-01-01

    Band-to-band registration, geodetic registration, interdector noise, and the modulation transfer function (MTE) are discussed for the Palmer County; TX scene. Band combinations for several LANDSAT 4 and LANDSAT 5 scenes; the geodetic registration test for the Sacramento, CA area; periodic noise components in TM band 5; and grey level measurements by detector for Great Salt Lake (UT) dark water forescans and backscans are considered. Results of MTF analyses of the San Mateo Bridge and of TM high resolution and aerial Daedalus scanner imagery are consistent and appear to be repeatable. An oil-on-sand target was constructed on the White Sands Missile Range in New Mexico. The two-image analysis procedure used is summarized.

  13. Relationships between Western Area Power Administration`s power marketing program and hydropower operations at Salt Lake City area integrated projects

    Energy Technology Data Exchange (ETDEWEB)

    Veselka, T.D.; Folga, S.; Poch, L.A. [and others

    1995-03-01

    This technical memorandum provides background information on the Western Area Power Administration (Western) and the physical characteristics of the Salt Lake City Area Integrated Projects (SLCA/IP) hydropower plants, which include the Colorado River Storage Project, the Rio Grande Project, and the Collbran Project. In addition, the history, electrical capacity, storage capacity, and flow restrictions at each dam are presented. An overview of Western`s current programs and services, including a review of statutory authorities, agency discretion, and obligations, is also provided. The variability of SLCA/IP hourly generation under various alternative marketing strategies and purchasing programs is discussed. The effects of Western`s services, such as area load control, outage assistance, and transmission, on SLCA/IP power plant operations are analyzed.

  14. Testing a high resolution CO2 and CO emission inventory against atmospheric observations in Salt Lake City, Utah for policy applications

    Science.gov (United States)

    Mendoza, D. L.; Lin, J. C.; Mitchell, L.; Gurney, K. R.; Patarasuk, R.; Mallia, D. V.; Fasoli, B.; Bares, R.; Catharine, D.; O'Keeffe, D.; Song, Y.; Huang, J.; Horel, J.; Crosman, E.; Hoch, S.; Ehleringer, J. R.

    2016-12-01

    We address the need for robust highly-resolved emissions and trace gas concentration data required for planning purposes and policy development aimed at managing pollutant sources. Adverse health effects resulting from urban pollution exposure are the result of proximity to emission sources and atmospheric mixing, necessitating models with high spatial and temporal resolution. As urban emission sources co-emit carbon dioxide (CO2) and criteria air pollutants (CAPs), efforts to reduce specific pollutants would synergistically reduce others. We present a contemporary (2010-2015) emissions inventory and modeled CO2 and carbon monoxide (CO) concentrations for Salt Lake County, Utah. We compare emissions transported by a dispersion model against stationary measurement data and present a systematic quantification of uncertainties. The emissions inventory for CO2 is based on the Hestia emissions data inventory that resolves emissions at hourly, building and road-link resolutions, as well as on an hourly gridded scale. The emissions were scaled using annual Energy Information Administration (EIA) fuel consumption data. We derived a CO emissions inventory using methods similar to Hestia, downscaling total county emissions from the 2011 Environmental Protection Agency's (EPA) National Emissions Inventory (NEI). The gridded CO emissions were compared against the Hestia CO2 gridded data to characterize spatial similarities and differences between them. Correlations were calculated at multiple scales of aggregation. The Stochastic Time-Inverted Lagrangian Trasport (STILT) dispersion model was used to transport emissions and estimate pollutant concentrations at an hourly resolution. Modeled results were compared against stationary measurements in the Salt Lake County area. This comparison highlights spatial locations and hours of high variability and uncertainty. Sensitivity to biological fluxes as well as to specific economic sectors was tested by varying their contributions to

  15. Total- and methyl-mercury concentrations and methylation rates across the freshwater to hypersaline continuum of the Great Salt Lake, Utah, USA

    Science.gov (United States)

    Johnson, William P.; Swanson, Neil; Black, Brooks; Rudd, Abigail; Carling, Gregory; Fernandez, Diego P.; Luft, John; Van Leeuwen, Jim; Marvin-DiPasquale, Mark C.

    2015-01-01

    We examined mercury (Hg) speciation in water and sediment of the Great Salt Lake and surrounding wetlands, a locale spanning fresh to hypersaline and oxic to anoxic conditions, in order to test the hypothesis that spatial and temporal variations in Hg concentration and methylation rates correspond to observed spatial and temporal trends in Hg burdens previously reported in biota. Water column, sediment, and pore water concentrations of methylmercury (MeHg) and total mercury (THg), as well as related aquatic chemical parameters were examined. Inorganic Hg(II)-methylation rates were determined in selected water column and sediment subsamples spiked with inorganic divalent mercury (204Hg(II)). Net production of Me204Hg was expressed as apparent first-order rate constants for methylation (kmeth), which were also expanded to MeHg production potential (MPP) rates via combination with tin reducible ‘reactive’ Hg(II) (Hg(II)R) as a proxy for bioavailable Hg(II). Notable findings include: 1) elevated Hg concentrations previously reported in birds and brine flies were spatially proximal to the measured highest MeHg concentrations, the latter occurring in the anoxic deep brine layer (DBL) of the Great Salt Lake; 2) timing of reduced Hg(II)-methylation rates in the DBL (according to both kmeth and MPP) coincides with reduced Hg burdens among aquatic invertebrates (brine shrimp and brine flies) that act as potential vectors of Hg propagation to the terrestrial ecosystem; 3) values ofkmeth were found to fall within the range reported by other studies; and 4) MPP rates were on the lower end of the range reported in methodologically comparable studies, suggesting the possibility that elevated MeHg in the anoxic deep brine layer results from its accumulation and persistence in this quasi-isolated environment, due to the absence of light (restricting abiotic photo demethylation) and/or minimal microbiological demethylation.

  16. Position paper on the applicability of supplemental standards to the uppermost aquifer at the Uranium Mill Tailings Vitro Processing Site, Salt Lake City, Utah

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This report documents the results of the evaluation of the potential applicability of supplemental standards to the uppermost aquifer underlying the Uranium Mill Tailings Remedial Action (UMTRA) Project, Vitro Processing Site, Salt Lake City, Utah. There are two goals for this evaluation: provide the landowner with information to make an early qualitative decision on the possible use of the Vitro property, and evaluate the proposed application of supplemental standards as the ground water compliance strategy at the site. Justification of supplemental standards is based on the contention that the uppermost aquifer is of limited use due to wide-spread ambient contamination not related to the previous site processing activities. In support of the above, this report discusses the site conceptual model for the uppermost aquifer and related hydrogeological systems and establishes regional and local background water quality. This information is used to determine the extent of site-related and ambient contamination. A risk-based evaluation of the contaminants` effects on current and projected land uses is also provided. Reports of regional and local studies and U.S. Department of Energy (DOE) site investigations provided the basis for the conceptual model and established background ground water quality. In addition, a limited field effort (4 through 28 March 1996) was conducted to supplement existing data, particularly addressing the extent of contamination in the northwestern portion of the Vitro site and site background ground water quality. Results of the field investigation were particularly useful in refining the conceptual site model. This was important in light of the varied ground water quality within the uppermost aquifer. Finally, this report provides a critical evaluation, along with the related uncertainties, of the applicability of supplemental standards to the uppermost aquifer at the Salt Lake City Vitro processing site.

  17. Total- and methyl-mercury concentrations and methylation rates across the freshwater to hypersaline continuum of the Great Salt Lake, Utah, USA.

    Science.gov (United States)

    Johnson, William P; Swanson, Neil; Black, Brooks; Rudd, Abigail; Carling, Greg; Fernandez, Diego P; Luft, John; Van Leeuwen, Jim; Marvin-DiPasquale, Mark

    2015-04-01

    We examined mercury (Hg) speciation in water and sediment of the Great Salt Lake and surrounding wetlands, a locale spanning fresh to hypersaline and oxic to anoxic conditions, in order to test the hypothesis that spatial and temporal variations in Hg concentration and methylation rates correspond to observed spatial and temporal trends in Hg burdens previously reported in biota. Water column, sediment, and pore water concentrations of methylmercury (MeHg) and total mercury (THg), as well as related aquatic chemical parameters were examined. Inorganic Hg(II)-methylation rates were determined in selected water column and sediment subsamples spiked with inorganic divalent mercury (204Hg(II)). Net production of Me204Hg was expressed as apparent first-order rate constants for methylation (kmeth), which were also expanded to MeHg production potential (MPP) rates via combination with tin reducible 'reactive' Hg(II) (Hg(II)R) as a proxy for bioavailable Hg(II). Notable findings include: 1) elevated Hg concentrations previously reported in birds and brine flies were spatially proximal to the measured highest MeHg concentrations, the latter occurring in the anoxic deep brine layer (DBL) of the Great Salt Lake; 2) timing of reduced Hg(II)-methylation rates in the DBL (according to both kmeth and MPP) coincides with reduced Hg burdens among aquatic invertebrates (brine shrimp and brine flies) that act as potential vectors of Hg propagation to the terrestrial ecosystem; 3) values of kmeth were found to fall within the range reported by other studies; and 4) MPP rates were on the lower end of the range reported in methodologically comparable studies, suggesting the possibility that elevated MeHg in the anoxic deep brine layer results from its accumulation and persistence in this quasi-isolated environment, due to the absence of light (restricting abiotic photo demethylation) and/or minimal microbiological demethylation. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Relationships of surface water, pore water, and sediment chemistry in wetlands adjacent to Great Salt Lake, Utah, and potential impacts on plant community health.

    Science.gov (United States)

    Carling, Gregory T; Richards, David C; Hoven, Heidi; Miller, Theron; Fernandez, Diego P; Rudd, Abigail; Pazmino, Eddy; Johnson, William P

    2013-01-15

    We collected surface water, pore water, and sediment samples at five impounded wetlands adjacent to Great Salt Lake, Utah, during 2010 and 2011 in order to characterize pond chemistry and to compare chemistry with plant community health metrics. We also collected pore water and sediment samples along multiple transects at two sheet flow wetlands during 2011 to investigate a potential link between wetland chemistry and encroachment of invasive emergent plant species. Samples were analyzed for a suite of trace and major elements, nutrients, and relevant field parameters. The extensive sampling campaign provides a broad assessment of Great Salt Lake wetlands, including a range of conditions from reference to highly degraded. We used nonmetric multidimensional scaling (NMS) to characterize the wetland sites based on the multiple parameters measured in surface water, pore water, and sediment. NMS results showed that the impounded wetlands fall along a gradient of high salinity/low trace element concentrations to low salinity/high trace element concentrations, whereas the sheet flow wetlands have both elevated salinity and high trace element concentrations, reflecting either different sources of element loading or different biogeochemical/hydrological processes operating within the wetlands. Other geochemical distinctions were found among the wetlands, including Fe-reducing conditions at two sites and sulfate-reducing conditions at the remaining sites. Plant community health metrics in the impounded wetlands showed negative correlations with specific metal concentrations in sediment (THg, Cu, Zn, Cd, Sb, Pb, Ag, Tl), and negative correlations with nutrient concentrations in surface water (nitrite, phosphate, nitrate). In the sheet flow wetlands, invasive plant species were inversely correlated with pore water salinity. These results indicate that sediment and pore water chemistry play an important role in wetland plant community health, and that monitoring and

  19. Geographic scale matters in detecting the relationship between neighbourhood food environments and obesity risk: an analysis of driver license records in Salt Lake County, Utah.

    Science.gov (United States)

    Fan, Jessie X; Hanson, Heidi A; Zick, Cathleen D; Brown, Barbara B; Kowaleski-Jones, Lori; Smith, Ken R

    2014-08-19

    Empirical studies of the association between neighbourhood food environments and individual obesity risk have found mixed results. One possible cause of these mixed findings is the variation in neighbourhood geographic scale used. The purpose of this paper was to examine how various neighbourhood geographic scales affected the estimated relationship between food environments and obesity risk. Cross-sectional secondary data analysis. Salt Lake County, Utah, USA. 403,305 Salt Lake County adults 25-64 in the Utah driver license database between 1995 and 2008. Utah driver license data were geo-linked to 2000 US Census data and Dun & Bradstreet business data. Food outlets were classified into the categories of large grocery stores, convenience stores, limited-service restaurants and full-service restaurants, and measured at four neighbourhood geographic scales: Census block group, Census tract, ZIP code and a 1 km buffer around the resident's house. These measures were regressed on individual obesity status using multilevel random intercept regressions. Obesity. Food environment was important for obesity but the scale of the relevant neighbourhood differs for different type of outlets: large grocery stores were not significant at all four geographic scales, limited-service restaurants at the medium-to-large scale (Census tract or larger) and convenience stores and full-service restaurants at the smallest scale (Census tract or smaller). The choice of neighbourhood geographic scale can affect the estimated significance of the association between neighbourhood food environments and individual obesity risk. However, variations in geographic scale alone do not explain the mixed findings in the literature. If researchers are constrained to use one geographic scale with multiple categories of food outlets, using Census tract or 1 km buffer as the neighbourhood geographic unit is likely to allow researchers to detect most significant relationships. Published by the BMJ

  20. Desulfonatronobacter acetoxydans sp. nov., : A first acetate-oxidizing, extremely salt-tolerant alkaliphilic SRB from a hypersaline soda lake

    NARCIS (Netherlands)

    Sorokin, D.Y.; Chernyh, N.A.; Poroshina, M.N.

    2015-01-01

    Recent intensive microbiological investigation of sulfidogenesis in soda lakes did not result in isolation of any pure cultures of sulfate-reducing bacteria (SRB) able to directly oxidize acetate. The sulfate-dependent acetate oxidation at haloalkaline conditions has, so far, been only shown in two

  1. Audit reports timeliness: Empirical evidence from Tunisia

    National Research Council Canada - National Science Library

    Fakhfakh Sakka, Imen; Jarboui, Anis

    2016-01-01

    .... The purpose of this paper is to examine the relationship between corporate governance, external auditor's characteristics index, and timeliness in light of the recent amendments to the Financial Security Law (2005) in Tunisia...

  2. Energy, pollution, and economic development in Tunisia

    Directory of Open Access Journals (Sweden)

    Miniar Ben Ammar Sghari

    2016-11-01

    The rising level of energy consumption that is occurring internationally also is being mirrored at regional and national levels. An interesting case study along these lines is Tunisia, which is one of the high-growth economies in the Middle East and North African area yet lacks sufficient energy supply to satisfy its growing demand. Tunisia looks like many nations around the world with a young population, growing economy, increasing domestic energy consumption, and the need to balance economic development with environmental concerns.

  3. Drought occurrence analysis in Tunisia

    Science.gov (United States)

    Touati, Salima; Hermassi, Taoufik; Habaieb, Hamadi

    2017-04-01

    Droughtis a terrible scourge for the Tunisianeconomybasedmainly on rainfed agricultural production. The analysis of the recurrence and the persistence of thisphenomenon by scientificmethodsseeks to establish a probabilityestimatewhichcouldcontribute to the planning of strategies for the mobilization and management of water resources. This paperaims on the analysis of the occurrence and the persistence of the meteorologicaldrought in Tunisia by Markov chain. It isbased on monthly data for 115 yearsfrom 24 rainfall stations distributed over the Tunisianterritory. The studyshowedthatdroughtis a frequentphenomenonrecurringeverytwoyears or eventhreeyears or more. The probability of havingtwoconsecutive dry yearsisgreater in the western regions (the Northwest, the Center-West, and the Southwest). Theseregions are known for their agricultural production and theireconomic contribution. The application of the standardizedprecipitation index showedthat the Tunisianclimateisoftenfrequented by mild to moderateweatherdroughts. Theseresultscontribute to the establishment of astrategy to combat drought.

  4. Seismotectonics and seismic Hazard map of Tunisia

    Science.gov (United States)

    Soumaya, Abdelkader; Ben Ayed, Noureddine; Khayati Ammar, Hayet; Kadri, Ali; Zargouni, Fouad; Ghanmi, Mohamed

    2016-04-01

    One natural hazard in Tunisia is caused by earthquakes and one way to measure the shaking risk is the probabilistic seismic-hazard map. The study of seismic hazard and risk assessment in Tunisia started in 1990 within the framework of the National Program for Assessment of Earthquake Risk. Because earthquakes are random events characterized by specific uncertainties, we used a probabilistic method to build the seismic hazard map of Tunisia. Probabilities were derived from the available seismic data and from results of neotectonic, geophysical and geological studies on the main active domains of Tunisia. This map displays earthquake ground motions for various probability levels across Tunisia and it is used in seismic provisions of building codes, insurance rate structures, risk assessment and other public management activities. The product is a seismotectonic map of Tunisia summarizing the available datasets (e.g., active fault, focal mechanism, instrumental and historical seismicity, peak ground acceleration). In addition, we elaborate some thematic seismic hazard maps that represent an important tool for the social and economic development.

  5. Seismotectonic and Seismic Hazard Map of Tunisia

    Science.gov (United States)

    Soumaya, A.; Ben Ayed, N.; Khayati Ammar, H.; Tayech, M.; Ghanmi, M.

    2016-12-01

    One natural hazard in Tunisia is caused by earthquakes and one way to measure the shaking risk is the probabilistic seismic-hazard map. The study of seismic hazard and risk assessment in Tunisia started in 1990 within the framework of the National Program for Assessment of Earthquake Risk. Because earthquakes are random events characterized by specific uncertainties, we used a probabilistic method to build the seismic hazard map of Tunisia. Probabilities were derived from the available seismic data and from results of neotectonic, geophysical and geological studies on the main active domains of Tunisia. This map displays earthquake ground motions for various probability levels across Tunisia and it is used in seismic provisions of building codes, insurance rate structures, risk assessment and other public management activities. The product is a seismotectonic map of Tunisia summarizing the available datasets (e.g., active fault, focal mechanism, instrumental and historical seismicity, peak ground acceleration). In addition, we elaborate some thematic seismic hazard maps that represent an important tool for the social and economic development.

  6. Holocene and latest Pleistocene paleoseismology of the Salt Lake City segment of the Wasatch Fault Zone, Utah, at the Penrose Drive Trench Site

    Science.gov (United States)

    DuRoss, Christopher B.; Hylland, Michael D.; McDonald, Greg N.; Crone, Anthony J.; Personius, Stephen F.; Gold, Ryan D.; Mahan, Shannon

    2014-01-01

    The Salt Lake City segment (SLCS) of the Wasatch fault zone (WFZ) and the West Valley fault zone (WVFZ) compromise Holocene-active normal faults that bound a large intrabasin graben in northern Salt Lake Valley and have evidence of recurrent, large-magnitude (M ~6-7) surface-faulting earthquakes. However, at the time of this investigation, questions remained regarding the timing, displacement, and recurrence of latest Pleistocene and Holocene earthquakes on the northern SLCS and WVFZ , and whether the WVFZ is seismically independent of, or moves coseismically with, the SLCS. To improve paleoseismic data for the SLCS, we conducted a fault-trench investigation at the Penrose Drive site on the northern SLCS. Two trenches, excavated across an 11-m-high scarp near the northern end of the East Bench fault, exposed colluvial-wedge evidence for fize of six (preferred) surface-faulting earthquakes postdating to Provo-phase shoreline of Lake Bonneville (~14-18 ka). Radiocarbon and luminescence ages support earthquake times at 4.0 ± 0.5 ka (2σ) (PD1), 5.9 ± 0.7 ka (PD2), 7.5 ± 0.8 ka (PD3a), 9.7 ± 1.1 ka (PD3b), 10.9 ± 0.2 ka (PD4), and 12.1 ± 1.6 ka (PD5). At least one additional earthquake occurred at 16.5 ± 1.9 ka (PD6) based on an erosional unconformity that separates deformed Lake Bonneville sily and flat-lying Provo-phase shoreline gravel. Earthquakes PD5-PD1 yield latest Pleistocene (post-Provo) and Holocene mean recurrence intervals of ~1.6 kyr and ~1.7-1.9 kyr, respectively. Using 1.0-1.4 m of per-event vertical displacement for PD5-PD3b corroborate previously identified SLCS earthquakes at 4-10 ka. PD4 and PD5 occurred within an ~8-kyr *17-9 ka) time interval on the SLCS previously interpreted as a period of seismic quiescence, and PD6 possibly corresponds with a previously identified earthquake at ~17 ka (although both events have large timing uncertainties). The Penrose data, when combined with previous paleoseismic results, improve the latest Pleistocene

  7. tunisia

    African Journals Online (AJOL)

    lanez

    31 déc. 2014 ... ABSTRACT. The aim of this study is to evaluate mainly the conditions the milking and the mammary health status of cows in the central East Sousse (Tunisian Sahel). The study was conducted on a sample of 20 small and means dairy cattle herds aboveground divided into two study areas. This study.

  8. Trace elements and organic compounds in sediment and fish tissue from the Great Salt Lake basins, Utah, Idaho, and Wyoming, 1998-99

    Science.gov (United States)

    Waddell, Kidd M.; Giddings, Elise M.

    2004-01-01

    A study to determine the occurrence and distribution of trace elements, organochlorine pesticides, polychlorinated biphenyls (PCBs), and semivolatile organic compounds in sediment and in fish tissue was conducted in the Great Salt Lake Basins study unit of the National Water-Quality Assessment (NAWQA) program during 1998-99. Streambed-sediment and fish-tissue samples were collected concurrently at 11 sites and analyzed for trace-element concentration. An additional four sites were sampled for streambed sediment only and one site for fish tissue only. Organic compounds were analyzed from streambed-sediment and fish-tissue samples at 15 sites concurrently.Bed-sediment cores from lakes, reservoirs, and Farmington Bay collected by the NAWQA program in 1998 and by other researchers in 1982 were used to examine historical trends in trace-element concentration and to determine anthropogenic sources of contaminants. Cores collected in 1982 from Mirror Lake, a high-mountain reference location, showed an enrichment of arsenic, cadmium, copper, lead, tin, and zinc in the surface sediments relative to the deeper sediments, indicating that enrichment likely began after about 1900. This enrichment was attributed to atmospheric deposition during the period of metal-ore mining and smelting. A core from Echo Reservoir, in the Weber River Basin, however, showed a different pattern of trace-element concentration that was attributed to a local source. This site is located downstream from the Park City mining district, which is the most likely historical source of trace elements. Cores collected in 1998 from Farmington Bay show that the concentration of lead began to increase after 1842 and peaked during the mid-1980s and has been in decline since. Recent sediments deposited during 1996-98 indicate a 41- to 62-percent reduction since the peak in the mid-1980s.The concentration of trace elements in streambed sediment was greatest at sites that have been affected by historic mining

  9. Analysis of nitrate and volatile organic compound data for ground water in the Great Salt Lake Basins, Utah, Idaho, and Wyoming, 1980-98

    Science.gov (United States)

    Thiros, Susan A.

    2000-01-01

    In 1995, ground water was the source of drinking water to about 52 percent of the population served by public drinking water systems in the Great Salt Lake Basins study unit, which includes parts of Utah, Idaho, and Wyoming. Existing nitrate and volatile organic compound data for ground water collected in the study unit were compiled and summarized as part of the National Water-Quality Assessment Program’s objective to describe water-quality conditions in the Nation’s aquifers. Prerequisites for the inclusion of nitrate and volatile organic compound data into this retrospective analysis are that the data set is available in electronic form, the data were collected during 1980-98, the data set is somewhat regional in coverage, and the locations of the sampled sites are known. Ground-water data stored in the U.S. Geological Survey’s National Water Information System and the Idaho and Utah Public Drinking Water Systems databases were reviewed. Only the most recent analysis was included in the data sets if more than one analysis was available for a site.The National Water Information System data set contained nitrate analyses for water from 480 wells. The median concentration of nitrate was 1.30 milligrams per liter for the 388 values above minimum reporting limits. The maximum contaminant level for nitrate as established by the U.S. Environmental Protection Agency was exceeded in water from 10 of the 200 wells less than or equal to 150 feet deep and in water from 3 of 280 wells greater than 150 feet deep. The Public Drinking Water Systems data set contained nitrate analyses for water from 587 wells. The median concentration of nitrate was 1.12 milligrams per liter for the 548 values above minimum reporting limits. The maximum contaminant level for nitrate was exceeded at 1 site and 22 sites had concentrations equal to or greater than 5 milligrams per liter. The types of land use surrounding a well and the well depth were related to measured nitrate

  10. Insights from the metagenome of an acid salt lake: the role of biology in an extreme depositional environment.

    Directory of Open Access Journals (Sweden)

    Sarah Stewart Johnson

    Full Text Available The extremely acidic brine lakes of the Yilgarn Craton of Western Australia are home to some of the most biologically challenging waters on Earth. In this study, we employed metagenomic shotgun sequencing to generate a microbial profile of the depositional environment associated with the sulfur-rich sediments of one such lake. Of the 1.5 M high-quality reads generated, 0.25 M were mapped to protein features, which in turn provide new insights into the metabolic function of this community. In particular, 45 diverse genes associated with sulfur metabolism were identified, the majority of which were linked to either the conversion of sulfate to adenylylsulfate and the subsequent production of sulfide from sulfite or the oxidation of sulfide, elemental sulfur, and thiosulfate via the sulfur oxidation (Sox system. This is the first metagenomic study of an acidic, hypersaline depositional environment, and we present evidence for a surprisingly high level of microbial diversity. Our findings also illuminate the possibility that we may be meaningfully underestimating the effects of biology on the chemistry of these sulfur-rich sediments, thereby influencing our understanding of past geobiological conditions that may have been present on Earth as well as early Mars.

  11. Spatiotemporal comparison of highly-resolved emissions and concentrations of carbon dioxide and criteria pollutants in Salt Lake City, Utah for health and policy applications

    Science.gov (United States)

    Mendoza, D. L.; Lin, J. C.; Mitchell, L.; Gurney, K. R.; Patarasuk, R.; Fasoli, B.; Bares, R.; o'Keefe, D.; Song, T.; Huang, J.; Horel, J.; Crosman, E.; Ehleringer, J. R.

    2015-12-01

    This study addresses the need for robust highly-resolved emissions and concentration data required for planning purposes and policy development aimed at managing pollutant sources. Adverse health effects resulting from urban pollution exposure are dependent on proximity to emission sources and atmospheric mixing, necessitating models with high spatial and temporal resolution. As urban emission sources co-emit carbon dioxide (CO2) and criteria pollutants (CAPs), efforts to reduce specific pollutants would synergistically reduce others. We present emissions inventories and modeled concentrations for CO2 and CAPs: carbon monoxide (CO), lead (Pb), nitrogen oxides (NOx), particulate matter (PM2.5 and PM10), and sulfur oxides (SOx) for Salt Lake County, Utah. We compare the resulting concentrations against stationary and mobile measurement data and present a systematic quantification of uncertainties. The emissions inventory for CO2 is based on the Hestia emissions data inventory that resolves emissions at an hourly, building and road link resolution as well as hourly gridded emissions with a 0.002o x 0.002o spatial resolution. Two methods for deriving criteria pollutant emission inventories were compared. One was constructed using methods similar to Hestia but downscales total emissions based on the 2011 National Emissions Inventory (NEI). The other used Emission Modeling Clearinghouse spatial and temporal surrogates to downscale the NEI data from annual and county-level resolution to hourly and 0.002o x 0.002o grid cells. The gridded emissions from both criteria pollutant methods were compared against the Hestia CO2 gridded data to characterize spatial similarities and differences between them. Correlations were calculated at multiple scales of aggregation. The CALPUFF dispersion model was used to transport emissions and estimate air pollutant concentrations at an hourly 0.002o x 0.002o resolution. The resulting concentrations were spatially compared in the same manner

  12. Review of alien marine macrophytes in Tunisia

    Directory of Open Access Journals (Sweden)

    Y. R. SGHAIER

    2015-01-01

    Full Text Available In the present study, the list of alien marine macrophytes introduced into Tunisia was updated in the light of available data and new observations. A total of 27 alien marine macrophytes have been recorded so far from Tunisia: 18 Rhodophyta, 3 Ochrophyta, 5 Chlorophyta and 1 Magnoliophyta. For each species, the locality (-ies, the year (or period and the source of the first observation in Tunisia are given. The distribution and the status (casual, cryptogenic, established or questionable of species in Tunisia were evaluated and, where appropriate, discussed. Among them, Hypnea cornuta is reported for the first time from Tunisia. Fourteen alien marine macrophytes are established, whereas seven cryptogenic and two casual species require further investigation. Eleven species are considered as invasive or potentially invasive in the Mediterranean Sea: Acrothamnion preissii, Asparagopsis armata, A. taxiformis Indo-Pacific lineage, Hypnea cornuta, Lophocladia lallemandii, Womersleyella setacea, Caulerpa chemnitzia, C. cylindracea, C. taxifolia, Codium fragile subsp. fragile and Halophila stipulacea. Finally, the case of four questionable species is also discussed.

  13. Tunisia: high fertility stalls development.

    Science.gov (United States)

    Barberis, M

    1985-01-01

    Despite government policy enacted in 1964 to reduce fertility in order to hasten socioeconomic progress, population pressures continue to impair development in Tunisia. The birth rate fell 20% over the last 2 decades, but this accomplishment has been outweighed by a 50% decline in mortality rates. As a result, the rate of natural population increase has remained relatively constant at 2.5%/year. The initial decline in fertility that followed introduction of the national family planning program appears to have reached a plateau, explained in part by the resurgence of conservatism and religious fundamentalism and the consequent emphasis on women's childbearing roles. Unemployment in rural areas has led to widespread migration and unemployment is as high as 20% in the nonagricultural sector. Many young Tunisians lack adequate educational preparation to enter the labor force; in 1982, 27% of new job entrants could not read or write. The government's plan to decentralize development to stabilize population and achieve equilibrium between regions has been thwarted by the pace of population growth and limited resources. The rural regions where population is increasing the fastest are also the most difficult to reach with family planning programs. On the other hand, there have been some successes in this area when services have been adapted to the lifestyle and traditions of those in these isolated rural villages.

  14. Marsh wrens as bioindicators of mercury in wetlands of Great Salt Lake: do blood and feathers reflect site-specific exposure risk to bird reproduction?

    Science.gov (United States)

    Hartman, C Alex; Ackerman, Joshua T; Herring, Garth; Isanhart, John; Herzog, Mark

    2013-06-18

    Nonlethal sampling of bird blood and feathers are among the more common ways of estimating the risk of mercury exposure to songbird reproduction. The implicit assumption is that mercury concentrations in blood or feathers of individuals captured in a given area are correlated with mercury concentrations in eggs from the same area. Yet, this assumption is rarely tested. We evaluated mercury concentrations in blood, feathers, and eggs of marsh wrens in wetlands of Great Salt Lake, Utah, and, at two spatial scales, specifically tested the assumption that mercury concentrations in blood and feather samples from birds captured in a defined area were predictive of mercury concentrations in eggs collected in the same area. Mercury concentrations in blood were not correlated with mercury concentrations in eggs collected within the same wetland unit, and were poorly correlated with mercury concentrations in eggs collected at the smaller home range spatial scale of analysis. Moreover, mercury exposure risk, as estimated via tissue concentrations, differed among wetland units depending upon whether blood or egg mercury concentrations were sampled. Mercury concentrations in feathers also were uncorrelated with mercury concentrations in eggs, and were poorly correlated with mercury concentrations in blood. These results demonstrate the potential for contrasting management actions that may be implemented based solely on the specific avian tissue that is sampled, and highlight the importance of developing avian tissues as biomonitoring tools for assessing local risk of mercury exposure to bird reproduction.

  15. Novel Halomonas sp. B15 isolated from Larnaca Salt Lake in Cyprus that generates vanillin and vanillic acid from ferulic acid.

    Science.gov (United States)

    Vyrides, Ioannis; Agathangelou, Maria; Dimitriou, Rodothea; Souroullas, Konstantinos; Salamex, Anastasia; Ioannou, Aristostodimos; Koutinas, Michalis

    2015-08-01

    Vanillin is a high value added product with many applications in the food, fragrance and pharmaceutical industries. A natural and low-cost method to produce vanillin is by microbial bioconversions through ferulic acid. Until now, limited microorganisms have been found capable of bioconverting ferulic acid to vanillin at high yield. This study aimed to screen halotolerant strains of bacteria from Larnaca Salt Lake which generate vanillin and vanillic acid from ferulic acid. From a total of 50 halotolenant/halophilic strains 8 grew in 1 g/L ferulic acid and only 1 Halomonas sp. B15 and 3 Halomonas elognata strains were capable of bioconverting ferulic acid to vanillic acid at 100 g NaCl/L. The highest vanillic acid (365 mg/L) at these conditions generated by Halomonas sp. B15 which corresponds to ferulic acid bioconversion yield of 36.5%. Using the resting cell technique with an initial ferulic acid concentration of 0.5 g/L at low salinity, the highest production of vanillin (245 mg/L) took place after 48 h, corresponding to a bioconversion yield of 49%. This is the first reported Halomonas sp. with high yield of vanillin production from ferulic acid at low salinity.

  16. Marsh wrens as bioindicators of mercury in wetlands of Great Salt Lake: do blood and feathers reflect site-specific exposure risk to bird reproduction?

    Science.gov (United States)

    Hartman, C. Alex; Ackerman, Joshua T.; Herring, Garth; Isanhart, John; Herzog, Mark P.

    2013-01-01

    Nonlethal sampling of bird blood and feathers are among the more common ways of estimating the risk of mercury exposure to songbird reproduction. The implicit assumption is that mercury concentrations in blood or feathers of individuals captured in a given area are correlated with mercury concentrations in eggs from the same area. Yet, this assumption is rarely tested. We evaluated mercury concentrations in blood, feathers, and eggs of marsh wrens in wetlands of Great Salt Lake, Utah, and, at two spatial scales, specifically tested the assumption that mercury concentrations in blood and feather samples from birds captured in a defined area were predictive of mercury concentrations in eggs collected in the same area. Mercury concentrations in blood were not correlated with mercury concentrations in eggs collected within the same wetland unit, and were poorly correlated with mercury concentrations in eggs collected at the smaller home range spatial scale of analysis. Moreover, mercury exposure risk, as estimated via tissue concentrations, differed among wetland units depending upon whether blood or egg mercury concentrations were sampled. Mercury concentrations in feathers also were uncorrelated with mercury concentrations in eggs, and were poorly correlated with mercury concentrations in blood. These results demonstrate the potential for contrasting management actions that may be implemented based solely on the specific avian tissue that is sampled, and highlight the importance of developing avian tissues as biomonitoring tools for assessing local risk of mercury exposure to bird reproduction.

  17. A combined noble gas and {sup 40}Ar-{sup 39}Ar study of Salt Lake Crater xenolith SL322 from Oahu, Hawaii

    Energy Technology Data Exchange (ETDEWEB)

    Trieloff, M. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Rocholl, A. [Heidelberg Univ. (Germany). Mineralogisch-Petrographisches Inst.; Jessberger, E.K. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)]|[Muenster Univ. (Germany). Inst. fuer Planetologie

    1998-12-31

    The microdistribution of noble gases in a garnet pyroxenite nodule from Salt Lake Crater (SLC), Oahu, Hawaii, was investigated by a detailed step-heating and -crushing analysis and a {sup 40}Ar-{sup 39}Ar-study. A noble gas component with MORB type argon, helium and neon resides in CO{sub 2}-rich fluid inclusions trapped in <30 km depth. This component was most probably derived from the nephelinitic SLC host magma and confirms the dominance of MORB type noble gases in the late post-erosional magmatic stages of Hawaiian volcanism, as suggested previsouly (Kurz et al., 1983; Valbracht et al., 1996). A second previously detected (Rocholl et al., 1996) low {sup 40}Ar/{sup 36}Ar ({proportional_to}5000) component turned out to be associated with two different reservoirs. The larger reservoir is most probably related to garnet, the other one is associated with low retentive sites containing few K and Cl and could not yet be adequately identified. The low {sup 40}Ar/{sup 36}Ar ({proportional_to}5000) component hosted by garnet can be interpreted as a mixture of MORB and plume type noble gas components with specific {sup 4}He/{sup 40}Ar ratios. The results demonstrate the complexity of the microdistribution of noble gases in ultramafic nodules and allow insight into plume induced metasomatism of the Hawaiian lithosphere. (orig.)

  18. Class 1 overview of cultural resources for the Western Area Power Administration Salt Lake City Area Integrated Projects electric power marketing environmental impact statement

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, K.L.; Malinowski, L.M.; Hoffecker, J.F.; Walitschek, D.A.; Shogren, L.; Mathews, J.E.; Verhaaren, B.T.

    1993-11-01

    Argonne National Laboratory conducted an inventory of known archaeological and historic sites in areas that could be affected by the hydropower operation alternatives under analysis in the power marketing environmental impact statement for the Western Area Power Administration`s Salt Lake City Area Integrated Projects. The study areas included portions of the Green River (Flaming Gorge Dam to Cub Creek) in Utah and Colorado and the Gunnison River (Blue Mesa Reservoir to Crystal Dam) in Colorado. All previous archaeological surveys and previously recorded prehistoric and historic sites, structures, and features were inventoried and plotted on maps (only survey area maps are included in this report). The surveys were classified by their level of intensity, and the sites were classified according to their age, type, and contents. These data (presented here in tabular form) permit a general assessment of the character and distribution of archaeological remains in the study areas, as well as an indication of the sampling basis for such an assessment. To provide an adequate context for the descriptions of the archaeological and historic sites, this report also presents overviews of the environmental setting and the regional prehistory, history, and ethnography for each study area.

  19. Lake Cadagno

    DEFF Research Database (Denmark)

    Tonolla, Mauro; Storelli, Nicola; Danza, Francesco

    2017-01-01

    Lake Cadagno (26 ha) is a crenogenic meromictic lake located in the Swiss Alps at 1921 m asl with a maximum depth of 21 m. The presence of crystalline rocks and a dolomite vein rich in gypsum in the catchment area makes the lake a typical “sulphuretum ” dominated by coupled carbon and sulphur...... cycles. The chemocline lies at about 12 m depth, stabilized by density differences of salt-rich water supplied by sub-aquatic springs to the monimolimnion and of electrolyte-poor surface water feeding the mixolimnion. Steep sulphide and light gradients in the chemocline support the growth of a large...... in the chemocline. Small-celled PSB together with the sulfate-reducing bacterium Desulfocapsa thiozymogenes sp. form stable aggregates in the lake, which represent small microenvironments with an internal sulphur cycle. Eukaryotic primary producers in the anoxic zones are dominated by Cryptomonas phaseolus...

  20. Halls Lake 1990

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Salt marsh habitats along the shoreline of Halls Lake are threatened by wave erosion, but the reconstruction of barrier islands to reduce this erosion will modify or...

  1. Probability distribution of flood flows in Tunisia

    Science.gov (United States)

    Abida, H.; Ellouze, M.

    2008-05-01

    L (Linear) moments are used in identifying regional flood frequency distributions for different zones Tunisia wide. 1134 site-years of annual maximum stream flow data from a total of 42 stations with an average record length of 27 years are considered. The country is divided into two homogeneous regions (northern and central/southern Tunisia) using a heterogeneity measure, based on the spread of the sample L-moments among the sites in a given region. Then, selection of the corresponding distribution is achieved through goodness-of-fit comparisons in L-moment diagrams and verified using an L moment based regional test that compares observed to theoretical values of L-skewness and L-kurtosis for various candidate distributions. The distributions used, which represent five of the most frequently used distributions in the analysis of hydrologic extreme variables are: (i) Generalized Extreme Value (GEV), (ii) Pearson Type III (P3), (iii) Generalized Logistic (GLO), (iv) Generalized Normal (GN), and (v) Generalized Pareto (GPA) distributions. Spatial trends, with respect to the best-fit flood frequency distribution, are distinguished: Northern Tunisia was shown to be represented by the GNO distribution while the GNO and GEV distributions give the best fit in central/southern Tunisia.

  2. [Mycetoma in Tunisia: a 15-case series].

    Science.gov (United States)

    Elgallali, N; El Euch, D; Cheikhrouhou, R; Belhadj, S; Chelly, I; Chaker, E; Ben Osman, A

    2010-06-01

    Mycetoma is a chronic infection of cutaneous and subcutaneous tissue that can be caused by fungi or bacteria. It is endemic in tropical and subtropical areas but rare in Tunisia. The purpose of this report is to describe epidemioclinical features, treatment and outcomes in patients presenting mycetoma in Tunisia. The files of all patients treated for mycetoma in the Dermatology Department of La Rabta Hospital in Tunisia from 1982 to 2006 were retrospectively reviewed. A total of 15 cases of mycetoma were recorded during the study period. There were 6 men and 9 women with a mean age of 53.2 years. The most common clinical presentation was infiltrated erythematous plaques with sinus tracts (fistulas). Lesions were located on the foot in 12 cases. Thirteen patients reported the presence of grains in fluid discharging from fistulas. The cause of mycetoma was actinomycetes, i.e., Actinomadura madurae, in 9 cases and fungus in 6 cases including 3 due to Madurella mycetomi and 2 to Pseudallesheria boydii. Treatment was based on oral antibiotics for actinomycetoma and oral antifungals for eumycetoma. Mycetoma in Tunisia is still uncommon with a slight female predominance. The foot is the most frequent location. Diagnosis can be accomplished by direct mycologic examination, culture, and histololgy. There is no consensus on treatment that is often prolonged with numerous relapses.

  3. Educational Television and Educational Development in Tunisia.

    Science.gov (United States)

    National Association of Educational Broadcasters, Washington, DC.

    The National Association of Educational Broadcasters attempted to determine how educational television and related technologies could strengthen the educational system of Tunisia. An overview of the Tunisian society is presented, followed by a brief history of the development of its educational system. The tremendous educational needs of the…

  4. River capture and sediment redistribution in northern Tunisia: The doom of Utica

    Science.gov (United States)

    Booth-Rea, Guillermo; Camafort, Miquel; Pérez-Peña, J. Vicente; Melki, Fetheddine; Ranero, César; Azañón, José Miguel; Gracia, Eulalia; Ouadday, Mohamed

    2016-04-01

    Utica was a flourishing port city in northern Tunisia since the Phoenician times, 12-9th century B.C., until the 4th century A.D.. However, at present it is located 10 km from the coastline after very fast late Holocene progradation of the Mejerda River delta into the bay of Utica. This fast delta progradation occurred after Mejerda River captured Tine River increasing 140 % the river catchment area. Charcoal fragments present in the youngest Tine river terrace at the wind gap give a conventional radiocarbon age of 3240 +/- 30yr BP, indicating that the capture occurred after this date. Quaternary fluvial terraces located in the Tine River paleovalley have been folded and uplifted above a fold related to the active El Alia Tebousouk reverse fault (ETF). Continued uplift of the Tine River valley above the ETF favoured headward erosion of the Medjerda river tributaries creating a transverse drainage that captured Tine River. This capture produced an important change in sediment discharge along the northern Tunisia coast driving sediments to the Gulf of Tunis instead of feeding the Tyrrhenian Sea through the Ichkeul and Bizerte lakes. Although anthropogenic derived degradation of northern Tunisia land for agricultural purposes probably influenced the increase in sediment into the Utica bay, the main cause of rapid progradation of the Medjerda River delta during the late Holocene is related to its increase in drainage area after capturing the Tine River. This process was mostly driven by local contractive tectonics linked to the seismogenic Alia Tebousouk reverse fault.

  5. Paraphenylenediamine Poisoning in Tunisia: A Case Report

    OpenAIRE

    Dorra Amira; Ines Gana; Anouar Nouioui; Fathia Khlifi; Dorra Ben Salah; Wafa Masri; Ines Belwaer; Hayet Ghorbel; Abderrazzek Hedili

    2015-01-01

    Paraphenylenediamine (PPD) represents the main active substance in the color of hair dyes. In Tunisia, PPD poisoning is very common, especially in rural areas where the consequences linked to this toxic substance are still unknown. In this paper, we report a case of PPD poisoning and confirm the diagnosis by a qualitative method of analysis. We discuss the clinical manifestations and study the kinetics of biological parameters during the monitoring of the poisoning. The main complication was ...

  6. Seroprevalence of Toscana virus infection in Tunisia.

    Science.gov (United States)

    Fezaa, Ons; Bahri, Olfa; Alaya Bouafif, Nissaf Ben; Triki, Henda; Bouattour, Ali

    2013-12-01

    The main objective of this study was to assess the prevalence of IgG antibodies against Toscana virus (TOSV) by an ELISA test and to determine the extent of its circulation in Tunisia. An indirect ELISA test was performed to detect anti-TOSV IgG. The results were compared to those of an indirect fluorescent antibody (IFA) test. The survey tested 494 healthy people from various regions of Tunisia by ELISA for anti-TOSV IgG; 47 people (9.5%) were found to be positive. Seroprevalence varied by bioclimatic region and gender. Two hundred and twelve samples, randomly chosen from the same selected population and tested with ELISA, were retested using an IFA for IgG antibodies. An 85% concordance between the IFA and ELISA was obtained (kappa=0.650). These serological data confirm the circulation of TOSV in different bioclimatic zones in Tunisia where the vector sand flies are found. The detection of IgG against TOSV suggests that the diagnosis of TOSV infection is often neglected, as this virus often causes asymptomatic infections, with only a few patients developing severe illnesses involving neurological manifestations. Copyright © 2013 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  7. Reclassification of Bacillus saliphilus as Alkalicoccus saliphilus gen. nov., comb. nov., and description of Alkalicoccus halolimnae sp. nov., a moderately halophilic bacterium isolated from a salt lake.

    Science.gov (United States)

    Zhao, Baisuo; Lu, Weidong; Zhang, Shanshan; Liu, Kang; Yan, Yanchun; Li, Jun

    2017-05-01

    A Gram-stain-positive, cocci-shaped, non-spore-forming and moderately halophilic bacterium, designed BZ-SZ-XJ29T, was isolated from a salt lake of China. On the basis of 16S rRNA gene sequence similarity, the closest phylogenetic relatives were Bacillus saliphilus 6AGT (97.3 % 16S rRNA gene sequence similarity) and five other species of the genus Bacillus(95.4-96.3 %). However, strain BZ-SZ-XJ29T shared only 89.5 % 16S rRNA gene sequence similarity with Bacillus subtilis subsp. subtilis DSM 10T, indicating that this isolate might not be a member of the genus Bacillus. The genomic DNA G+C content was 40.0 mol% (Tm). The DNA-DNA relatedness value with B. saliphilus 6AGT was 45±2 %. Strain BZ-SZ-XJ29T formed yellow pigment and grew in the presence of 0.74-4.15 M Na+ [optimum 1.42-2.10 M Na+], at pH 6.0-10.5 (optimum pH 7.5), and at 5-41 °C (optimum 33 °C). The predominant (>10 %) fatty acids were anteiso-C15 : 0 and anteiso-C15 : 0. The dominant polar lipids consisted of diphosphatidylglycerol and the respiratory quinone was menaquinone-7 (MK-7). The peptidoglycan type of the cell wall was A1γ, based on meso-diaminopimelic acid as the diagnostic diamino acid. On the basis of the combined phylogenetic data, phenotypic features and chemotaxonomic properties, it is proposed that B. saliphilus and strain BZ-SZ-XJ29T should be assigned to a single novel genus as two separate species. Bacillus. saliphilus is reclassified in a new genus, Alkalicoccus gen. nov., as Alkalicoccus saliphilus comb. nov., and is the type species of the new genus; the type strain of the type species is 6AGT (=DSM 15402T=ATCC BAA-957T). Strain BZ-SZ-XJ29T (=DSM 29191T=JCM 30193T=CGMCC 1.12936T) is placed in the genus Alkalicoccus as a novel species, Alkalicoccus halolimnae sp. nov.

  8. Helping communities control leishmaniasis in rural Tunisia | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-05-05

    May 5, 2016 ... This scarring, vector-borne disease has emerged as a major public health problem in Tunisia, as land use, water management practices, and climate change create conditions ripe for its spread. With more than 90% of its territory at risk of desertification, Tunisia's agricultural production is almost entirely ...

  9. Pathotypic diversity of Rhynchosporium secalis (Oudem) in Tunisia ...

    African Journals Online (AJOL)

    Scald, caused by Rhynchosporium secalis (Oudem), is an important disease of barley in Tunisia particularly in northern, northwestern and central parts of the country where the climate is usually cold and wet during most of the barley growing season. Pathogenic variability of the barley scald pathogen in Tunisia was ...

  10. Soil and Terrain Database for Tunisia primary data (version 1.0) - scale 1:1 million (SOTER_Tunisia)

    NARCIS (Netherlands)

    Dijkshoorn, J.A.; Nachtergaele, F.O.; Huting, J.R.M.

    2013-01-01

    The Soil and Terrain database for Tunisia primary data (version 1.0), at scale 1:1 million (SOTER_Tunisia), was compiled of enhanced soil information within the framework of the FAO's program of Land Degradation Assessment in Drylands (LADA). A SOTER database was compiled based on the digital soil

  11. Enterovirus Migration Patterns between France and Tunisia.

    Science.gov (United States)

    Othman, Ines; Mirand, Audrey; Slama, Ichrak; Mastouri, Maha; Peigue-Lafeuille, Hélène; Aouni, Mahjoub; Bailly, Jean-Luc

    2015-01-01

    The enterovirus (EV) types echovirus (E-) 5, E-9, and E-18, and coxsackievirus (CV-) A9 are infrequently reported in human diseases and their epidemiologic features are poorly defined. Virus transmission patterns between countries have been estimated with phylogenetic data derived from the 1D/VP1 and 3CD gene sequences of a sample of 74 strains obtained in France (2000-2012) and Tunisia (2011-2013) and from the publicly available sequences. The EV types (E-5, E-9, and E-18) exhibited a lower worldwide genetic diversity (respective number of genogroups: 4, 5, and 3) in comparison to CV-A9 (n = 10). The phylogenetic trees estimated with both 1D/VP1 and 3CD sequence data showed variations in the number of co-circulating lineages over the last 20 years among the four EV types. Despite the low number of genogroups in E-18, the virus exhibited the highest number of recombinant 3CD lineages (n = 10) versus 4 (E-5) to 8 (E-9). The phylogenies provided evidence of multiple transportation events between France and Tunisia involving E-5, E-9, E-18, and CV-A9 strains. Virus spread events between France and 17 other countries in five continents had high probabilities of occurrence as those between Tunisia and two European countries other than France. All transportation events were supported by BF values > 10. Inferring the source of virus transmission from phylogenetic data may provide insights into the patterns of sporadic and epidemic diseases caused by EVs.

  12. Coastal tourism and climate change in Tunisia

    Science.gov (United States)

    Henia, Latifa; Hlaoui, Zouhaier; Alouane, Tahar

    2014-05-01

    Tunisia is a major tourist destination on the southern shore of the Mediterranean. The tourism sector occupies an important place in the Tunisian economy with 816 hotels, 229,873 beds and a more than six million tourists at the end of the first decade of the 21th century, i.e. , more than half of the population. It offers a large number of direct and indirect jobs: One out of five people work in the tourism sector. The 1960s tourism boom was caused by a number of factors including long days of sunshine, 1,300 km of sandy coast, and a location close to Europe. Tunisian tourism is fundamentally based on two natural determinants: the sun and the sea. The coastline accounts for 95% of tourism investments and functional beds. The high season extends from April to October and it records 73% of nonresident tourists. This results in a homogenous growth of the "product" and its "consumers". This standardization is an important factor in the vulnerability of the Tunisian tourism to climate change. Global warming may affect the comfort level of the swimming season as well as its structure. An estimation of air and water temperature evolution near the Tunisian coasts was conducted under the CLIM-RUN project "Climate Local Information in the Mediterranean Region: Responding to User Needs" funded by the European Union's Seventh Framework Program (FP7). The University of Tunis research unit "GREVACHOT", project partner in charge of the case study of Tunisian tourism, has made the study of comfort indices of the present climate. This paper presents: - The climate comfort indices for seaside tourism in Tunisia, - The approach and results of the future evolution of air and water temperatures by the Tunisian coasts, - The future evolution of climate seaside comfort indices of Tunisia as well as the evolution of the swimming season in relation to global warming.

  13. Radiocarbon-insights into temporal variations in the sources and concentrations of carbonaceous aerosols in the Los Angeles and Salt Lake City Metropolitan Areas

    Science.gov (United States)

    Czimczik, Claudia; Mouteva, Gergana; Simon, Fahrni; Guaciara, Santos; James, Randerson

    2014-05-01

    Increased fossil fuel consumption and biomass burning are contributing to significantly larger emissions of black carbon (BC) aerosols to the atmosphere. Together with organic carbon (OC), BC is a major constituent of fine particulate matter in urban air, contributes to haze and has been linked to a broad array of adverse health effects. Black carbon's high light absorption capacity and role in key (in-)direct climate feedbacks also lead to a range of impacts in the Earth system (e.g. warming, accelerated snow melt, changes in cloud formation). Recent work suggests that regulating BC emissions can play an important role in improving regional air quality and reducing future climate warming. However, BC's atmospheric transport pathways, lifetime and magnitudes of emissions by sector and region, particularly emissions from large urban centers, remain poorly constrained by measurements. Contributions of fossil and modern sources to the carbonaceous aerosol pool (corresponding mainly to traffic/industrial and biomass-burning/biogenic sources, respectively) can be quantified unambiguously by measuring the aerosol radiocarbon (14C) content. However, accurate 14C-based source apportionment requires the physical isolation of BC and OC, and minimal sample contamination with extraneous carbon or from OC charring. Compound class-specific 14C analysis of BC remains challenging due to very small sample sizes (5-15 ug C). Therefore, most studies to date have only analyzed the 14C content of the total organic carbonaceous aerosol fraction. Here, we present time-series 14C data of BC and OC from the Los Angeles (LA) metropolitan area in California - one of two megacities in the United States - and from Salt Lake City (SLC), UT. In the LA area, we analyzed 48h-PM10 samples near the LA port throughout 2007 and 2008 (with the exception of summer). We also collected monthly-PM2.5 samples at the University of California - Irvine, with shorter sampling periods during regional wildfire

  14. Volcano crisis response at Yellowstone volcanic complex - after-action report for exercise held at Salt Lake City, Utah, November 15, 2011

    Science.gov (United States)

    Pierson, Thomas C.; Driedger, Carolyn L.; Tilling, Robert I.

    2013-01-01

    A functional tabletop exercise was run on November 14-15, 2011 in Salt Lake City, Utah, to test crisis response capabilities, communication protocols, and decision-making by the staff of the multi-agency Yellowstone Volcano Observatory (YVO) as they reacted to a hypothetical exercise scenario of accelerating volcanic unrest at the Yellowstone caldera. The exercise simulated a rapid build-up of seismic activity, ground deformation, and hot-spring water-chemistry and temperature anomalies that culminated in a small- to moderate-size phreatomagmatic eruption within Yellowstone National Park. The YVO scientific team's responses to the unfolding events in the scenario and to simulated requests for information by stakeholders and the media were assessed by (a) the exercise organizers; (b) several non-YVO scientists, who observed and queried participants, and took notes throughout the exercise; and (c) the participants themselves, who kept logs of their actions during the exercise and later participated in a group debriefing session and filled out detailed questionnaires. These evaluations were tabulated, interpreted, and summarized for this report, and on the basis of this information, recommendations have been made. Overall, the YVO teams performed their jobs very well. The exercise revealed that YVO scientists were able to successfully provide critical hazards information, issue information statements, and appropriately raise alert levels during a fast-moving crisis. Based on the exercise, it is recommended that several measures be taken to increase YVO effectiveness during a crisis: 1. Improve role clarification within and between YVO science teams. 2. Improve communications tools and protocols for data-sharing and consensus-building among YVO scientists, who are geographically and administratively dispersed among various institutions across the United States. 3. Familiarize YVO staff with Incident Command System (ICS) procedures and protocols, and provide more in

  15. Salinibacter iranicus sp. nov. and Salinibacter luteus sp. nov., isolated from a salt lake, and emended descriptions of the genus Salinibacter and of Salinibacter ruber.

    Science.gov (United States)

    Makhdoumi-Kakhki, Ali; Amoozegar, Mohammad Ali; Ventosa, Antonio

    2012-07-01

    Two Gram-staining-negative, red- and orange-pigmented, non-motile, rod-shaped, extremely halophilic bacteria, designated strains CB7(T) and DGO(T), were isolated from Aran-Bidgol salt lake, Iran. Growth occurred at NaCl concentrations of between 2 and 5 M NaCl and the isolates grew optimally with 3 M NaCl. The optimum pH and temperature for growth of the two strains were pH 7.5 and 37 °C, and they were able to grow over pH and temperature ranges of pH 6-8 and 25-50 °C. The predominant fatty acids of the two isolates were C(18:1)ω7c, iso-C(15:0) and summed feature 3 (C(16:1)ω7c and/or iso-C(15:0) 2-OH). The polar lipid pattern of the two isolates consisted of diphosphatidylglycerol, phosphatidylcholine, three unidentified lipids, one unidentified aminolipid and three unidentified glycolipids. The only quinone present was menaquinone 7 (MK-7). The G+C contents of the genomic DNA of strains CB7(T) and DGO(T) were 64.8 and 65.6 mol%, respectively. 16S rRNA gene sequence analysis indicated that strains CB7(T) and DGO(T) were related to Salinibacter ruber in the phylum Bacteroidetes. Levels of 16S rRNA gene sequence similarity between strains CB7(T) and DGO(T) and Salinibacter ruber DSM 13855(T) were 93.2 and 93.6%, respectively. The two novel strains shared 98.9% 16S rRNA gene sequence similarity. DNA-DNA hybridization experiments between strains CB7(T) and DGO(T) and Salinibacter ruber DSM 13855(T) indicated levels of relatedness of 44 and 52%, respectively, while the level of relatedness between the two new isolates was 53%. Chemotaxonomic data supported the placement of strains CB7(T) and DGO(T) in the genus Salinibacter. DNA-DNA hybridization studies and biochemical and physiological characterization allowed strains CB7(T) and DGO(T) to be differentiated from Salinibacter ruber and from each other. They are therefore considered to represent two novel species of the genus Salinibacter, for which the names Salinibacter iranicus sp. nov. (type strain CB7(T

  16. Virtual water balance estimation in Tunisia

    Science.gov (United States)

    Stambouli, Talel; Benalaya, Abdallah; Ghezal, Lamia; Ali, Chebil; Hammami, Rifka; Souissi, Asma

    2015-04-01

    The water in Tunisia is limited and unevenly distributed in the different regions, especially in arid zones. In fact, the annual rainfall average varies from less than 100 mm in the extreme South to over 1500 mm in the extreme North of the country. Currently, the conventional potential of water resources of the country is estimated about 4.84 billion m³ / year of which 2.7 billion cubic meters / year of surface water and 2.14 billion cubic meters / year of groundwater, characterizing a structural shortage for water safety in Tunisia (under 500m3/inhabitant/year). With over than 80% of water volumes have been mobilized for agriculture. The virtual water concept, defined by Allan (1997), as the amount of water needed to generate a product of both natural and artificial origin, this concept establish a similarity between product marketing and water trade. Given the influence of water in food production, virtual water studies focus generally on food products. At a global scale, the influence of these product's markets with water management was not seen. Influence has appreciated only by analyzing water-scarce countries, but at the detail level, should be increased, as most studies consider a country as a single geographical point, leading to considerable inaccuracies. The main objective of this work is the virtual water balance estimation of strategic crops in Tunisia (both irrigated and dry crops) to determine their influence on the water resources management and to establish patterns for improving it. The virtual water balance was performed basing on farmer's surveys, crop and meteorological data, irrigation management and regional statistics. Results show that the majority of farmers realize a waste of the irrigation water especially at the vegetable crops and fruit trees. Thus, a good control of the cultural package may result in lower quantities of water used by crops while ensuring good production with a suitable economic profitability. Then, the virtual water

  17. Paraphenylenediamine Poisoning in Tunisia: A Case Report

    Directory of Open Access Journals (Sweden)

    Dorra Amira

    2015-05-01

    Full Text Available Paraphenylenediamine (PPD represents the main active substance in the color of hair dyes. In Tunisia, PPD poisoning is very common, especially in rural areas where the consequences linked to this toxic substance are still unknown. In this paper, we report a case of PPD poisoning and confirm the diagnosis by a qualitative method of analysis. We discuss the clinical manifestations and study the kinetics of biological parameters during the monitoring of the poisoning. The main complication was renal failure and the treatment was basically symptomatic.

  18. [Epidemiological changes of paediatric urolithiasis in Tunisia].

    Science.gov (United States)

    Alaya, Akram; Nouri, Abdellatif; F Najjar, Mohamed

    2012-07-01

    The clinical and biological characteristics of urolithiasis in children are still evolving in our country. Since the eighties no study has been conducted to determine incidence of urolithiasis in Tunisia. To define the current status of urolithiasis in Tunisian children. The records of 414 children with urolithiasis treated between 1983 and 2007 were found in a multi-centric study which took into consideration to age, sex, and history diagnosis and physical, laboratory, and radiologic findings. Clinical and biological date were performed in 344 cases. Stone analysis was performed by spectrophotometry. The incidence of paediatric urolithiasis has steadily decreased from 0.7/ 10 000 of the child population / year in 1991-1994 to 0.1 cases/10 000 children/ year in 2007. There was a continuous decrease in bladder stone over the past 25 years (47.1% in 1982-1986 Vs 10.2% in 2002-2007). Stones were homogeneous in 31.4% of cases. The main component was calcium oxalate stones in 36.4% of the cases. Since the eighties the increase of oxalates stones (15.6% in eighties Vs 51.5% actually) were with depends to purines and struvite stones. Epidemiologic characteristics of the urinary lithiasis (sex, age, localization and composition) have changed in Tunisia, due to the the improvements of standard of living. The occidentalization of the nutritional practices and the receding of the culinary traditions gave birth to new risks of urolithiasis characterized by the emergence of calcium oxalate stones.

  19. [Social determinants of contraceptive use in Tunisia].

    Science.gov (United States)

    Dimassi, K; Douik, F; Douzi, M A; Saidi, O; Ben Romdhane, H

    2017-02-01

    In Tunisia, the "Revolution" of January 2011 highlighted significant regional disparities and social inequalities in access to health care, including reproductive health services. The purpose of this study was to analyze the social determinants of the use of contraception in Tunisia. A cross-sectional national study conducted in 2012; on a sample of 15 to 49-year married women (n=4374) drawn by a two levels random sampling. Prevalence of contraception and its association factors were assessed. Logistic regression was used to evaluate the variation of contraception prevalence with area of residence, age, level of education, number of children and household income. The prevalence of contraception was 66.4 %. Eighty-two percent of women used a modern contraceptive method. The use of contraceptive methods was significantly dependent on the age (PTunisia, precursor Arab country in family planning, is recording a slowdown in the use of contraception in comparison with other countries of North Africa. Social determinants, such as, age, living conditions, area of residence and level of education are indicators to consider when targeting interventions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  20. Microbial diversity in the hypersaline Lake Meyghan, Iran

    NARCIS (Netherlands)

    Naghoni, A.; Emtiazi, G.; Amoozegar, M.A.; Cretoiu, M.S.; Stal, L.J.; Etemadifar, Z.; Shahzadeh Fazeli, S.A.; Bolhuis, H.

    2017-01-01

    Lake Meyghan is one of the largest and commercially most important salt lakes in Iran. Despite its inland location and high altitude, Lake Meyghan has a thalassohaline salt composition suggesting a marine origin. Inputs of fresh water by rivers and rainfall formed various basins characterized by

  1. Bacterial voltage-gated sodium channels (BacNa(V)s) from the soil, sea, and salt lakes enlighten molecular mechanisms of electrical signaling and pharmacology in the brain and heart.

    Science.gov (United States)

    Payandeh, Jian; Minor, Daniel L

    2015-01-16

    Voltage-gated sodium channels (Na(V)s) provide the initial electrical signal that drives action potential generation in many excitable cells of the brain, heart, and nervous system. For more than 60years, functional studies of Na(V)s have occupied a central place in physiological and biophysical investigation of the molecular basis of excitability. Recently, structural studies of members of a large family of bacterial voltage-gated sodium channels (BacNa(V)s) prevalent in soil, marine, and salt lake environments that bear many of the core features of eukaryotic Na(V)s have reframed ideas for voltage-gated channel function, ion selectivity, and pharmacology. Here, we analyze the recent advances, unanswered questions, and potential of BacNa(V)s as templates for drug development efforts. Copyright © 2014. Published by Elsevier Ltd.

  2. Inventory of the spontaneous alien flora in Tunisia. Sayari, N. and Mekki, M. (Tunisia)

    OpenAIRE

    Najla Sayari; Mounir Mekki

    2016-01-01

    The first step in any management strategy to control plant invasion is the compilation of a national and regional inventory of alien plant species. In this paper, we present a comprehensive inventory of the spontaneous alien vascular flora of Tunisia, including accepted names, family, biological form, habitat type, native origin, and invasive status. National flora accounts were the main source of information. Data were completed with new flora records and field surveys. The Raunk...

  3. Cultivation-dependent assessment, diversity, and ecology of haloalkaliphilic bacteria in arid saline systems of southern Tunisia.

    Science.gov (United States)

    El Hidri, Darine; Guesmi, Amel; Najjari, Afef; Cherif, Hanen; Ettoumi, Besma; Hamdi, Chadlia; Boudabous, Abdellatif; Cherif, Ameur

    2013-01-01

    Haloalkaliphiles are polyextremophiles adapted to grow at high salt concentrations and alkaline pH values. In this work, we isolated 122 haloalkaliphilic bacteria upon enrichments of 23 samples from 5 distinct saline systems of southern Tunisia, growing optimally in media with 10% salt and at pH 10. The collection was classified into 44 groups based on the amplification of the 16S-23S rRNA internal transcribed spacers (ITS-PCR). Phylogenetic analysis and sequencing of the 16S rRNA genes allowed the identification of 13 genera and 20 distinct species. Three gram-positive isolates showing between 95 and 96% of 16S rRNA sequence homology with Bacillus saliphilus could represent new species or genus. Beside the difference in bacterial diversity between the studied sites, several species ecological niches correlations were demonstrated such as Oceanobacillus in salt crust, Nesterenkonia in sand, and Salinicoccus in the rhizosphere of the desert plant Salicornia. The collection was further evaluated for the production of extracellular enzymes. Activity tests showed that gram-positive bacteria were mostly active, particularly for protease, lipase, DNase, and amylase production. Our overall results demonstrate the huge phenotypic and phylogenetic diversity of haloalkaliphiles in saline systems of southern Tunisia which represent a valuable source of new lineages and metabolites.

  4. Plant diversity in different bioclimatic zones in Tunisia

    Directory of Open Access Journals (Sweden)

    Hana You

    2016-03-01

    Full Text Available The Republic of Tunisia, located in northern Africa, faces various environmental challenges caused by anthropogenic practices such as overgrazing, deforestation, and desertification. The conversion of natural ecosystems is the major cause of plant biodiversity loss. Tunisia can be divided into three main climatic zones as follows: a northern Mediterranean climate zone, a central steppe climate zone, and a southern desert climate zone. Because of this great environmental diversity, there are distinctive vegetation and various genetic resources in Tunisia. This research was conducted to investigate plant biodiversity within the various bioclimatic zones and to characterize useful plant resources in Tunisia. We investigated native, medicinal and aromatic, desert, and soil erosion control plant species.

  5. Clustering of Risk Factors With Smoking Habits Among Adults, Sousse, Tunisia

    Science.gov (United States)

    Harrabi, Imed; Hmad, Sonia; Belkacem, Mylene; al’Absi, Mustafa; Lando, Harry; Ghannem, Hassen

    2013-01-01

    Introduction In Tunisia, few studies have assessed the association between tobacco use and other lifestyle risk factors for chronic disease (eg, unhealthy diet, physical inactivity). We studied 1,880 adults to determine the association between tobacco use and other lifestyle risk factors in Tunisia. Methods This study was part of an assessment of the prevalence of chronic disease risk factors in a community-based trial conducted in 2009 to implement a chronic disease prevention program. The study population was randomly selected from 3 districts of the region of Sousse. The questionnaires were administered by personal interview and included the assessment of tobacco use and other chronic disease risk factors such as unhealthful diet habits and physical inactivity. Results Of the 1,880 study participants, 64% were women. The mean age of the participants was 37.9 (standard deviation, 13.5 y). The prevalence of tobacco use in our population was 50.4% for men and 3.1% for women. Among men, the proportion of alcohol consumption was significantly higher among smokers (25.3% vs 5.7% [P <.001]). Smokers consumed fewer fruits and vegetables and more high-fat, high-salt, and high-sugar foods than did nonsmokers. There was no significant difference between male smokers and nonsmokers regarding physical activity (P = .36). Conclusion Physical activity and dietary characteristics may be important areas for physicians to assess during smoking-cessation interventions. PMID:24355104

  6. Modeling olive-crop forecasting in Tunisia

    Science.gov (United States)

    Ben Dhiab, Ali; Ben Mimoun, Mehdi; Oteros, Jose; Garcia-Mozo, Herminia; Domínguez-Vilches, Eugenio; Galán, Carmen; Abichou, Mounir; Msallem, Monji

    2017-05-01

    Tunisia is the world's second largest olive oil-producing region after the European Union. This paper reports on the use of models to forecast local olive crops, using data for Tunisia's five main olive-producing areas: Mornag, Jemmel, Menzel Mhiri, Chaal, and Zarzis. Airborne pollen counts were monitored over the period 1993-2011 using a Cour trap. Forecasting models were constructed using agricultural data (harvest size in tonnes of fruit/year) and data for several weather-related and phenoclimatic variables (rainfall, humidity, temperature, Growing Degree Days, and Chilling). Analysis of these data revealed that the amount of airborne pollen emitted over the pollen season as a whole (i.e., the Pollen Index) was the variable most influencing harvest size. Findings for all local models also indicated that the amount, timing, and distribution of rainfall (except during blooming) had a positive impact on final olive harvests. Air temperature also influenced final crop yield in three study provinces (Menzel Mhiri, Chaal, and Zarzis), but with varying consequences: in the model constructed for Chaal, cumulative maximum temperature from budbreak to start of flowering contributed positively to yield; in the Menzel Mhiri model, cumulative average temperatures during fruit development had a positive impact on output; in Zarzis, by contrast, cumulative maximum temperature during the period prior to flowering negatively influenced final crop yield. Data for agricultural and phenoclimatic variables can be used to construct valid models to predict annual variability in local olive-crop yields; here, models displayed an accuracy of 98, 93, 92, 91, and 88 % for Zarzis, Mornag, Jemmel, Chaal, and Menzel Mhiri, respectively.

  7. Communities structure of the planktonic halophiles in the solar saltern of Sfax, Tunisia

    Science.gov (United States)

    Elloumi, Jannet; Carrias, Jean-François; Ayadi, Habib; Sime-Ngando, Télesphore; Bouaïn, Abderrahmen

    2009-01-01

    The composition and distribution of the main planktonic halophilic micro-organisms (heterotrophic and autotrophic picoplankton, nanoplankton, phytoplankton, ciliates) and metazooplankton were investigated in six ponds of increasing salinity in the solar salt works of Sfax, Tunisia, from January to December 2003. Marked changes in the composition and biomass of the communities were found along the salinity gradient, especially at salinities of 150 and 350. Autotrophic picoplankton, nanoplankton, diatoms, dinoflagellates and ciliates characterized the less salted ponds. Planktonic biomass was the highest at intermediate salinity as a consequence of a bloom of Ochromonas. Species richness of phytoplankton, ciliates and zooplankton greatly decrease above a salinity of 150 and typical halophiles ( Dunaliella salina, cyanobacteria, Fabrea salina and Artemia salina) were found between 150 and 350 salinity. In this environment, F. salina appeared more adapted than the brine shrimp to survive during phytoplankton blooms. The halophilic plankton was however almost entirely composed of heterotrophic prokaryotes in the crystallizers. We thus observed a progressive disappearance of the autotrophic planktonic communities along the salinity gradient. Multivariate analysis of the communities provides evidence that ponds represent discrete aquatic ecosystems within this salt works.

  8. Season of birth and multiple sclerosis in Tunisia.

    Science.gov (United States)

    Sidhom, Youssef; Kacem, Imen; Bayoudh, Lamia; Ben Djebara, Mouna; Hizem, Yosr; Ben Abdelfettah, Sami; Gargouri, Amina; Gouider, Riadh

    2015-11-01

    Recent studies on date of birth of multiple sclerosis (MS) patients showed an association between month of birth and the risk of developing MS. This association has not been investigated in an African country. We aimed to determine if the risk of MS is associated with month of birth in Tunisia. Data concerning date of birth for MS patients in Tunisia (n = 1912) was obtained. Birth rates of MS patients were compared with all births in Tunisia matched by year of birth (n = 11,615,912). We used a chi-squared analysis and the Hewitt's non-parametric test for seasonality. The distribution of births among MS patients compared with the control population was not different when tested by the chi-squared test. The Hewitt's test for seasonality showed an excess of births between May and October among MS patients (p = 0.03). The peak of Births of MS patients in Tunisia was in July and the nadir in December. Our data does support the seasonality hypothesis of month of birth as risk factor for MS in Tunisia. Low vitamin D levels during pregnancy could be a possible explanation that needs further investigation. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Patients’ attitude towards bedside teaching in Tunisia

    Science.gov (United States)

    El Mhamdi, Sana; Bouanene, Ines; Sriha, Asma; Soltani, Mohamed

    2015-01-01

    Objectives To assess patient' reaction towards bedside teaching at the University Hospital of Monastir (Tunisia) and to identify the factors that may influence it. Methods A cross-sectional study was conducted during December 2012 at the University Hospital of Monastir. Each department, except the psychiatric department and the intensive care units, was visited in one day. All inpatients present on the day of the study were interviewed by four trained female nurses using a structured questionnaire. Results Of the 401 patients approached, 356 (88.8%) agreed to participate. In general, the results demonstrate that patients were positive toward medical students’ participation. The highest acceptance rates were found in situations where there is no direct contact between the patient and the student (e.g. when reading their medical file, attending ward rounds and observing doctor examining them). As the degree of students’ involvement increased, the refusal rate increased. Gender, age, educational level, marital status and the extent of students’ involvement in patient’s care were identified as the main factors affecting patients’ attitude. Conclusion: Taking advantage of this attitude, valorizing patient role as educator and using further learning methods in situations where patient’s consent for student involvement was not obtained should be considered to guarantee optimal care and safety to patients and good medical education to future physicians. PMID:26706313

  10. Patients' attitude towards bedside teaching in Tunisia.

    Science.gov (United States)

    Ben Salah, Arwa; El Mhamdi, Sana; Bouanene, Ines; Sriha, Asma; Soltani, Mohamed

    2015-12-25

    To assess patient' reaction towards bedside teaching at the University Hospital of Monastir (Tunisia) and to identify the factors that may influence it. A cross-sectional study was conducted during December 2012 at the University Hospital of Monastir. Each department, except the psychiatric department and the intensive care units, was visited in one day. All inpatients present on the day of the study were interviewed by four trained female nurses using a structured questionnaire. Of the 401 patients approached, 356 (88.8%) agreed to participate. In general, the results demonstrate that patients were positive toward medical students' participation. The highest acceptance rates were found in situations where there is no direct contact between the patient and the student (e.g. when reading their medical file, attending ward rounds and observing doctor examining them). As the degree of students' involvement increased, the refusal rate increased. Gender, age, educational level, marital status and the extent of students' involvement in patient's care were identified as the main factors affecting patients' attitude. Taking advantage of this attitude, valorizing patient role as educator and using further learning methods in situations where patient's consent for student involvement was not obtained should be considered to guarantee optimal care and safety to patients and good medical education to future physicians.

  11. Social Security and Fighting Poverty in Tunisia

    Directory of Open Access Journals (Sweden)

    Hasna Khemili

    2018-02-01

    Full Text Available The objective of this study was to examine the role of social security in fighting poverty in Metlaoui, Tunisia, using survey data collected between July 2012 and January 2014, covering 200 poor households. We used questionnaire data, which gave a thorough analysis of the reactions, behavior, and strategies adopted by poor households as a result of various forms of risk. Social security has an effect on a number of different areas, including health, education, housing, and income. Our methodology explored both complete and partial risk-sharing, to investigate the impact of social security schemes on the strategies adopted by households to cope with economic shocks. The estimation results of different models showed that social security could help social security-covered households choose less costly strategies to cope with risks. However, the role of social security remains insufficient, given that covered households had less confidence in its services and they adopted strategies of self-insurance or income smoothing. Overall, the results showed that social security plays an important role in Metlaoui, but it remains insufficient, especially for households that are not covered by social security and are suffering from heavy health expenditures.

  12. INNER SALTS

    Science.gov (United States)

    been characterized include: (1) mesomeric phosphonium salts possessing phototropic properties; (2) pentavalent phosphorus compounds; and (3) a...Products that have been characterized include: (1) mesomeric phosphonium salts possessing phototropic properties; (2) pentavalent phosphorus compounds; and (3) a mesomeric inner salt . (Author)...Novel phosphonium and phosphorane compounds ere prepared by a variety of m hods from triphenylphosphine and methylene bromide. Products that have

  13. Influence of salts and pH on growth and activity of a novel facultatively alkaliphilic, extremely salt-tolerant, obligately chemolithoautotrophic sufur-oxidizing Gammaproteobacterium Thioalkalibacter halophilus gen. nov., sp. nov. from South-Western Siberian soda lakes.

    Science.gov (United States)

    Banciu, Horia L; Sorokin, Dimitry Y; Tourova, Tatyana P; Galinski, Erwin A; Muntyan, Maria S; Kuenen, J Gijs; Muyzer, Gerard

    2008-05-01

    A chemolithoautotrophic sulfur-oxidizing bacterium (SOB) strain ALCO 1 capable of growing at both near-neutral and extremely alkaline pH was isolated from hypersaline soda lakes in S-W Siberia (Altai, Russia). Strain ALCO 1 represents a novel separate branch within the halothiobacilli in the Gammaproteobacteria, which, so far, contained only neutro-halophilic SOB. On the basis of its unique phenotypic properties and distant phylogeny, strain ALCO 1 is proposed as a new genus and species Thioalkalibacter halophilus gen. nov. sp. nov. ALCO 1 was able to grow within a broad range of salinity (0.5-3.5 M of total sodium) with an optimum at around 1 M Na+, and pH (7.2-10.2, pHopt at around 8.5). Na+ was required for sulfur-dependent respiration in ALCO 1. The neutral (NaCl)-grown chemostat culture had a much lower maximum growth rate (micromax), respiratory activity and total cytochrome c content than its alkaline-grown counterpart. The specific concentration of osmolytes (ectoine and glycine-betaine) produced at neutral pH and 3 M NaCl was roughly two times higher than at pH 10 in soda. Altogether, strain ALCO 1 represents an interesting chemolithoautotrophic model organism for comparative investigations of bacterial adaptations to high salinity and pH.

  14. First genotype identification of Trichosporon asahii in Sfax, Tunisia.

    Science.gov (United States)

    Sellami, Hayet; Trabelsi, Houaida; Neji, Sourour; Amouri, Imen; Cheikhrouhou, Fatma; Makni, Fattouma; Ayadi, Ali

    2017-04-01

    The objectives of our study were species identification and genotyping of Trichosporon isolates collected at the Parasitology and Mycology Laboratory in Sfax, Tunisia. Molecular identification was carried out by analysing the IGS1 regions of the rDNA of 30 Trichosporon isolates. Trichosporon asahii was the most frequent species detected. Furthermore, four genotypes were identified in Tunisia: 1 (46.4 %), 4 (35.7 %), 7 (14.3 %) and 3 (3.6 %). In vitro antifungal susceptibility testing of the isolates showed that voriconazole exhibited the highest activity. This is the first reported study of genotype identification of T. asahii in Tunisia and even in the African continent.

  15. West Nile disease in Tunisia: an overview of 60 years.

    Science.gov (United States)

    Hammami, Salah; Hassine, Thameur Ben; Conte, Annamaria; Amdouni, Jihène; De Massis, Fabrizio; Sghaier, Soufiène; Hassen, Sonia Ben

    2017-09-30

    West Nile virus (WNV) is an arthropod borne virus of public health importance. The virus is a member of the genus Flavivirus and belongs to the Japanese encephalitis virus (JEV) antigenic complex under the Flaviviridae family. The WNV is continuously spreading across Tunisia especially in the coastal and Southern area of the country. The first human West Nile disease (WND) epidemic in Tunisia occurred in 1997, since then, the quantity and the extension of spillover effects increased constantly. However, the existing knowledge of factors triggering such events continues to be rather poor. The last epidemic WNV human meningitis and meningoencephalitis recorded in 2012, with 86 cases and 6 deaths, confirmed the failure of the current system in predicting new cases. This review, based on analysis of scientific papers published between 1970 and 2015, summarises the state of knowledge on WNV in Tunisia and highlights the existing knowledge and research gaps that need to be addressed.

  16. Salt budget for West Pond, Utah, April 1987 to June 1989

    Science.gov (United States)

    Wold, S.R.; Waddell, K.M.

    1994-01-01

    During operation of the West Desert pumping project, April 10. 1987, to June 30, 1989, data were collected as part of a monitoring program to evaluate the effects of pumping brine from Great Salt Lake into West Pond in northern Utah. The removal of brine from Great Sail was part of an effort to lower the level of Great Salt Lake when the water level was at a high in 1986. These data were used to prepare a salt budget that indicates about 695 million tons of salt or about 14.2 percent of salt contained in Great Salt Lake was pumped into West Pond. Of the 695 million tons of salt pumped into West Pond, 315 million tons (45 percent) were dissolved in West Pond, 71 million tons (10.2 percent) formed a salt crust at the bottom of the pond, 10 million tons (1.4 percent) infiltrated the subsurface areas inundated by storage in the pond, 88 million tons (12.7 percent) were withdrawn by American Magnesium Corporation, and 123 million tons (17.7 percent) discharged from the pond through the Newfoundland weir. About 88 million tons (13 percent) of the salt pumped from the lake could not be accounted for in the salt budget. About 94 million tons of salt (1.9 percent of the total salt in Great Salt Lake) flowed back to Great Salt Lake.

  17. The end-Cretaceous in the southwestern Tethys (Elles, Tunisia)

    DEFF Research Database (Denmark)

    Thibault, Nicolas Rudolph; Galbrun, Bruno; Gardin, Silvia

    2016-01-01

    An integrated study of magnetic mass susceptibility (MS), bulk stable isotopes and calcareous nannofossil paleoecological changes is undertaken on the late Maastrichtian of the Elles section, Tunisia, spanning the last ca. 1 Myr of the Cretaceous. A cyclostratigraphic analysis reveals the presence...... different age models. Calcareous nannofossil assemblages highlight a decrease in surface-water nutriency, but their species richness remains high through the latest Maastrichtian, indicating, in Tunisia, a weak impact of Deccan volcanism on calcareous nannoplankton diversity before the mass extinction....

  18. Coupling between Chemical and Meteorological Processes under Persistent Cold-Air Pool Conditions: Evolution of Wintertime PM2.5 Pollution Events and N2O5 Observations in Utah's Salt Lake Valley.

    Science.gov (United States)

    Baasandorj, Munkhbayar; Hoch, Sebastian W; Bares, Ryan; Lin, John C; Brown, Steven S; Millet, Dylan B; Martin, Randal; Kelly, Kerry; Zarzana, Kyle J; Whiteman, C David; Dube, William P; Tonnesen, Gail; Jaramillo, Isabel Cristina; Sohl, John

    2017-06-06

    The Salt Lake Valley experiences severe fine particulate matter pollution episodes in winter during persistent cold-air pools (PCAPs). We employ measurements throughout an entire winter from different elevations to examine the chemical and dynamical processes driving these episodes. Whereas primary pollutants such as NOx and CO were enhanced twofold during PCAPs, O3 concentrations were approximately threefold lower. Atmospheric composition varies strongly with altitude within a PCAP at night with lower NOx and higher oxidants (O3) and oxidized reactive nitrogen (N2O5) aloft. We present observations of N2O5 during PCAPs that provide evidence for its role in cold-pool nitrate formation. Our observations suggest that nighttime and early morning chemistry in the upper levels of a PCAP plays an important role in aerosol nitrate formation. Subsequent daytime mixing enhances surface PM2.5 by dispersing the aerosol throughout the PCAP. As pollutants accumulate and deplete oxidants, nitrate chemistry becomes less active during the later stages of the pollution episodes. This leads to distinct stages of PM2.5 pollution episodes, starting with a period of PM2.5 buildup and followed by a period with plateauing concentrations. We discuss the implications of these findings for mitigation strategies.

  19. [Diversity of diazotrophs in the sediments of hypersaline salt and soda lakes analyzed with the use of the nifH gene as a molecular marker].

    Science.gov (United States)

    Turova, T P; Slobodova, N V; Bumazhkin, B K; Sukhacheva, M V; Sorokin, D Iu

    2014-01-01

    Phylogenetic analysis of the nifH genes, encoding the Fe protein of the nitrogenas enzymatic complex, was carried out for pure cultures of anoxygenic phototrophic bacteria of diverse origin, as well as for heterotrophic alkaliphilic sulfate reducers isolated from saline and soda lakes. Topology of the nitrogenase tree correlated with that of the 16S rRNAgene tree to a considerable degree; which niade it possible to use the nifH gene as a molecular marker for investigation of diazotrophic bacterialcommunities in silty sediments of saline and sodalakes. Although diazotrophs were revealed in all environmentalsamples, their phylogenetic diversity was relatively low. Sulfate-reducing deltaproteobacteria and photo- and chemotrophicgammaproteobacteria were predominant in samples integrated over sediment thickness. Analysis of samples fromthe upper sediment layers revealed predominance of phototrophic diazotrophs of various phyla, including purple sulfur and nonsulfur proteobacteria, green nonsulfur bacteria, heliobacteria; and cyanobacteria. Some phylotypes could not be identified, probably indicating the presence of bacterial groups which have not yet been studied by conventional microbiological techniques.

  20. Measuring Entrepreneurial Activity in Egypt and Tunisia | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The Global Entrepreneurship Monitor (GEM) is a worldwide initiative assessing entrepreneurial activity in about 100 countries. The study will compare findings from GEM data collected post-Arab Spring (2012) with results from 2008-2010 for Egypt and Tunisia, two countries at the forefront of the Arab Spring. It will examine ...

  1. All projects related to Tunisia | Page 3 | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Region: Burkina Faso, Ivory Coast, Algeria, Egypt, Ghana, Guinea, Morocco, Tunisia, North of Sahara, South of Sahara. Program: Food, Environment, and Health. Total Funding: CA$ 2,467,086.00. Economic Reform, Firm Survival and Competitiveness (Middle East and North Africa). Project. During the 1980s, it was thought ...

  2. All projects related to Tunisia | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Project. After the optimism that accompanied the popular uprisings of 2011, reform in the Arab region today is losing momentum. Region: Algeria, Lebanon, Syria, Tunisia, France. Program: Governance and Justice. Total Funding: CA$ 552,000.00. Supporting democratic communities through enhanced youth participation.

  3. Virtual Water and Food Security in Tunisia | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Tunisia is an arid country, where water scarcity significantly limits agricultural production. As a result, the country imports most of its basic foods and all of its livestock feed, focusing its own agricultural production on high-value crops for export. Liberalization of agricultural trade and dependency on the world grain market has ...

  4. Blood meal analysis of culicoides (Diptera: ceratopogonidae) in central Tunisia.

    Science.gov (United States)

    Slama, Darine; Haouas, Najoua; Mezhoud, Habib; Babba, Hamouda; Chaker, Emna

    2015-01-01

    To evaluate the host preferences of Culicoides species (Diptera: Ceratopogonidae) in Central Tunisia, we identified the source of blood meals of field collected specimens by sequencing of the cytochrome b (cyt b) mitochondrial locus and Prepronociceptine single copy nuclear gene. The study includes the most common and abundant livestock associated species of biting midges in Tunisia: C. imicola, C. jumineri, C. newsteadi, C. paolae, C. cataneii, C. circumscriptus, C. kingi, C. pseudojumineri, C. submaritimus, C. langeroni, C. jumineri var and some unidentified C. species. Analysis of cyt b PCR products from 182 field collected blood-engorged females' midges revealed that 92% of them fed solely on mammalian species, 1.6% on birds, 2.4% on insects and 0.8% on reptiles. The blast results identified the blood origin of biting midges to the species level with exact or nearly exact matches (≥98%). The results confirm the presence of several Culicoides species, including proven vectors in Central Tunisia. Blood meal analyses show that these species will indeed feed on bigger mammals, thereby highlighting the risk that these viruses will be able to spread in Tunisia.

  5. Constitutional Reform and Emergency Powers in Egypt and Tunisia

    NARCIS (Netherlands)

    Zwitter, Andrej

    Legal mechanisms governing the state of emergency can play an important role in authoritarian rule and post-revolutionary transition periods. Egypt has experienced the terror of a regime empowered by emergency law. In Tunisia, emergency law was not so much an issue before but rather after the

  6. Morphological characterization of a Daucus L. germplasm collection in Tunisia

    Science.gov (United States)

    The genus Daucus includes about 25 recognized species worldwide. Northern Africa represents a major center of diversity of Daucus, with Tunisia containing at least 12 species and six subspecies. We assessed morphological diversity from a Daucus L. germplasm collection of 103 accessions at the Nation...

  7. Phenols, essential oils and carotenoids of Rosa canina from Tunisia ...

    African Journals Online (AJOL)

    The antioxidant activity of leaf extracts of Rosa canina from diverse localities of Tunisia were evaluated by ABTS and DPPH methods, whereas in those of essential oils and carotenoids extracts such activity was determined only by the ABTS method. Total phenols determined by the Folin method revealed that at Aindraham, ...

  8. All projects related to Tunisia | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Region: Algeria, Egypt, Iran, Iraq, Libya, Morocco, Syria, Tunisia, Turkey, Lebanon. Program: Governance and Justice. Total Funding: CA$ 550,000.00. Renegotiating Arab Civil-Military Relations: Political and Economic Governance in Transition. Project. At a time of unprecedented political transitions in the Arab world, this ...

  9. Predictors of smoking initiation among schoolchildren in Tunisia: a 4 ...

    African Journals Online (AJOL)

    Objective: To identify predictors of smoking initiation among non smoking Tunisian school children; and to propose efficient antismoking strategies in order to prevent smoking initiation. Methods: It was a cohort study surveying prospectively for four years pupils attending schools in Sousse city in Tunisia. 441 non smoking ...

  10. Farmers adapt to climate change in Tunisia | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    In Soukra, Tunisia, hundreds of low-income families live off the crops they grow. But in recent decades, that way of life has come under growing threat from urbanization and climate change. IDRC's Focus Cities Research Initiative financed a project undertaken by the Tunisian NGO Club UNESCO/ALECSO pour le savoir et ...

  11. The water footprint of Tunisia from an economic perspective

    NARCIS (Netherlands)

    Chouchane, Hatem; Hoekstra, Arjen Ysbert; Krol, Martinus S.; Mekonnen, Mesfin

    2015-01-01

    This paper quantifies and analyses the water footprint of Tunisia at national and sub-national level, assessing green, blue and grey water footprints for the period 1996–2005. It also assesses economic water and land productivities related to crop production for irrigated and rain-fed agriculture,

  12. All projects related to Tunisia | Page 3 | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2007-11-15

    Project. Until the end of the 1960s, the plain of Ariana-Soukra was a greenbelt adjacent to Tunis. Start Date: November 15, 2007. End Date: September 27, 2012. Topic: SLUMS, SOIL DEGRADATION, SOIL MANAGEMENT, LAND RECLAMATION, URBAN AGRICULTURE. Region: Tunisia, North of Sahara, South of Sahara.

  13. All projects related to Tunisia | Page 2 | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Topic: SLUMS, SOIL DEGRADATION, SOIL MANAGEMENT, LAND RECLAMATION, URBAN AGRICULTURE. Region: Africa, North of Sahara, Tunisia. Program: Climate Change. Total Funding: CA$ 1,204,521.00. Water, Health and Climate Change Adaptation in Africa. Project. In West and North Africa, climate variability is ...

  14. Selected Bibliography of Educational Materials: Algeria, Libya, Morocco, Tunisia.

    Science.gov (United States)

    Azzouz, Azzedine; And Others

    A 100-item bibliography with abstracts of books, newspaper articles, and periodical articles in English and French published predominantly in 1970 offers information on various aspects of education in Algeria, Libya, Morocco, and Tunisia. Emphasis is placed on sections dealing with: (1) educational philosophy, administration, statistics, and…

  15. The tardigrade fauna of Tunisia, with an integrative description of ...

    African Journals Online (AJOL)

    The current knowledge of the diversity and distribution of tardigrade species in northern Africa is scarce and far from satisfactory. In this paper we review old and provide new faunistic records for various regions of Tunisia. Among the newly recorded taxa, we found a new heterotardigrade Bryodelphax maculatus sp. nov.

  16. Soil property estimates for Tunisia derived from SOTER and WISE (SOTWIS-Tunisia, ver. 1.0)

    NARCIS (Netherlands)

    Batjes, N.H.

    2014-01-01

    This datasets describes a harmonized set of soil property estimates for Tunisia. It has been derived from the 1:1 million scale Soil and Terrain Database for the country (SOTER_TN, ver. 1.0) and the ISRIC-WISE soil profile database, using standardized taxonomy-based pedotransfer (taxotransfer)

  17. Challenges of Globalization: Morocco and Tunisia. Curriculum Projects. Fulbright-Hays Summer Seminars Abroad Program, 2001 (Morocco and Tunisia).

    Science.gov (United States)

    2002

    This publication contains a collection of curriculum projects developed by educators who were participants in the 2001 Fulbright-Hays Summer Seminars Abroad Program in Morocco and Tunisia. The 13 curriculum projects in the publication are entitled: "Women in Morocco, Artists and Artisans" (Virginia da Costa); "Cultures of…

  18. 3D ground‐motion simulations of Mw 7 earthquakes on the Salt Lake City segment of the Wasatch fault zone: Variability of long‐period (T≥1  s) ground motions and sensitivity to kinematic rupture parameters

    Science.gov (United States)

    Moschetti, Morgan P.; Hartzell, Stephen; Ramirez-Guzman, Leonardo; Frankel, Arthur; Angster, Stephen J.; Stephenson, William J.

    2017-01-01

    We examine the variability of long‐period (T≥1  s) earthquake ground motions from 3D simulations of Mw 7 earthquakes on the Salt Lake City segment of the Wasatch fault zone, Utah, from a set of 96 rupture models with varying slip distributions, rupture speeds, slip velocities, and hypocenter locations. Earthquake ruptures were prescribed on a 3D fault representation that satisfies geologic constraints and maintained distinct strands for the Warm Springs and for the East Bench and Cottonwood faults. Response spectral accelerations (SA; 1.5–10 s; 5% damping) were measured, and average distance scaling was well fit by a simple functional form that depends on the near‐source intensity level SA0(T) and a corner distance Rc:SA(R,T)=SA0(T)(1+(R/Rc))−1. Period‐dependent hanging‐wall effects manifested and increased the ground motions by factors of about 2–3, though the effects appeared partially attributable to differences in shallow site response for sites on the hanging wall and footwall of the fault. Comparisons with modern ground‐motion prediction equations (GMPEs) found that the simulated ground motions were generally consistent, except within deep sedimentary basins, where simulated ground motions were greatly underpredicted. Ground‐motion variability exhibited strong lateral variations and, at some sites, exceeded the ground‐motion variability indicated by GMPEs. The effects on the ground motions of changing the values of the five kinematic rupture parameters can largely be explained by three predominant factors: distance to high‐slip subevents, dynamic stress drop, and changes in the contributions from directivity. These results emphasize the need for further characterization of the underlying distributions and covariances of the kinematic rupture parameters used in 3D ground‐motion simulations employed in probabilistic seismic‐hazard analyses.

  19. Waterbirds of alkaline lakes in Western Uganda | Pomeroy | Journal ...

    African Journals Online (AJOL)

    Uganda's only alkaline lakes are found in the Queen Elizabeth Conservation Area and the adjoining Kyambura Wildlife Reserve. ... The lakes are important scenically, for ecotourism, and for the conservation of waterbirds and plants; whilst Lake Katwe's traditional production of salt is of considerable economic significance.

  20. New explorations along the northern shores of Lake Bonneville

    Science.gov (United States)

    Oviatt, Charles G.; Miller, D.M.

    1997-01-01

    This field trip begins in Salt Lake City and makes a clockwise circuit of Great Salt Lake, with primary objectives to observe stratigraphie and geomorphic records of Lake Bonneville. Stops include Stansbury Island, Puddle Valley, gravel pits at Lakeside and the south end of the Hogup Mountains, several stops in Curlew Valley and Hansel Valley, and a final stop at the north end of Great Salt Lake east of the Promontory Mountains. Stratigraphie observations at gravel-pit and natural exposures will be linked to interpretations of lake-level change, which were caused by climate change. Evidence of paleoseismic and volcanic activity will be discussed at several sites, and will be tied to the lacustrine stratigraphic record. The trip provides an overview of the history of Lake Bonneville and introduces participants to some new localities with excellent examples of Lake Bonneville landforms and stratigraphy.

  1. Salamander colonization of Chase Lake, Stutsman County, North Dakota

    Science.gov (United States)

    Mushet, David M.; McLean, Kyle I.; Stockwell, Craig A.

    2013-01-01

    Salt concentrations in lakes are dynamic. In the western United States, water diversions have caused significant declines in lake levels resulting in increased salinity, placing many aquatic species at risk (Galat and Robinson 1983, Beutel et al. 2001). Severe droughts can have similar effects on salt concentrations and aquatic communities (Swanson et al. 2003). Conversely, large inputs of water can dilute salt concentrations and contribute to community shifts (Euliss et al. 2004).

  2. Environmental Quality Assessment of Bizerte Lagoon (Tunisia) Using Living Foraminifera Assemblages and a Multiproxy Approach

    National Research Council Canada - National Science Library

    Alves Martins, Maria Virgínia; Zaaboub, Noureddine; Aleya, Lotfi; Frontalini, Fabrizio; Pereira, Egberto; Miranda, Paulo; Mane, Miguel; Rocha, Fernando; Laut, Lazaro; El Bour, Monia

    2015-01-01

    This study investigated the environmental quality of the Bizerte Lagoon (Tunisia) through an integrated approach that combined environmental, biogeochemical, and living benthic foraminiferal analyses...

  3. Salt cookbook

    CERN Document Server

    Saha, Anirban

    2015-01-01

    If you are a professional associated with system and infrastructure management, looking at automated infrastructure and deployments, then this book is for you. No prior experience of Salt is required.

  4. Lake Afdera: a threatened saline lake in Ethiopia | Getahun | SINET ...

    African Journals Online (AJOL)

    ... for salt extraction. This paper gives some insight on the most probable dangers on the ecology of the lake if such activity is allowed to take place before environmental impact assessment was conducted. SINET: Ethiopian Journal of Science Vol. 24, No. 1 (June 2001), pp. 127-131. Key words/phrases: Afdera, conservation ...

  5. A New Generation of Uprisings – from Tunisia to Slovenia

    Directory of Open Access Journals (Sweden)

    Andrej Kurnik

    2013-03-01

    Full Text Available The uprising in Tunisia, the occupation of public squares in Spain, the Occupy Wall Street movement, the global uprising on 15 October 2011 and the recent widespread demonstrations in Slovenia can be understood as the new generation of uprisings following the eruption of financial crisis. Those multitudinal expressions of indignation and quests for real democracy are expressions of the irreversible crisis of neoliberalism and representative democracy. From an examination of the defining traits of uprisings from Tunisia to Slovenia, one can define basic theoretical and practical dilemmas in the new ways of doing political encounters. These include the relationship between the social and political dimensions of uprisings, the relationship between heterogeneity and forms of political organization, how resistance against financialization prefigures emerging forms of direct democracy, how emerging movements address the issue of direct democracy and minority rights, and what theoretical practices can prevent the attenuation of the discourse of uprisings and enable the free production of enunciations.

  6. Airport malaria: report of four cases in Tunisia.

    Science.gov (United States)

    Siala, Emna; Gamara, Dhikrayet; Kallel, Kalthoum; Daaboub, Jabeur; Zouiten, Faiçal; Houzé, Sandrine; Bouratbine, Aïda; Aoun, Karim

    2015-01-28

    Four cases of airport malaria were notified for the first time in Tunisia during the summer of 2013. All patients were neighbours living within 2 km of Tunis International Airport. They had no history of travel to malarious countries, of blood transfusion or of intravenous drug use. Although malaria transmission had ceased in Tunisia since 1980, autochthonous infection by local Anopheles mosquitoes was initially considered. However, this diagnostic hypothesis was ruled out due to negative entomological survey and the absence of additional cases.All cases were caused by Plasmodium falciparum. Clinical presentation was severe (important thrombocytopaenia and parasitaemia), because of relatively important delay in diagnosis (average of seven days). This indicates the need to consider malaria while examining airport employees or people living near international airports presenting with fever of unknown origin. It also stresses the need for effective spraying of aircrafts coming from malarious areas.

  7. Tunisia : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Région: Tunisia, Turkey, Morocco, Egypt. Programme: Governance and Justice. Financement total : CA$ 149,600.00. La crise de l'État arabe - réforme des institutions et transition à la démocratie dans le monde arabe. Projet. Le présent projet permettra d'analyser trois institutions publiques de la Tunisie, de l'Égypte et du ...

  8. Orientation of the Fiscal Policy in Tunisia: Structural VAR Analysis

    Directory of Open Access Journals (Sweden)

    Wissem Khanfir

    2017-06-01

    Full Text Available The objective of this paper is to indicate the orientation of fiscal policy in Tunisia, using the structural budget balance, during the period 1972-2014. For this purpose, we estimate a structural VAR model consisting of the fiscal deficit to current GDP ratio and the volume of economic activity represented by the real GDP. We estimate bivariate structural VAR in order to decompose fiscal deficit fluctuations into different disturbances.

  9. Tunisia : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Région: Algeria, Lebanon, Syria, Tunisia. Programme: Governance and Justice. Financement total : CA$ 552,000.00. Soutien des communautés démocratiques par une augmentation de la participation des jeunes. Project. Un programme démocratique visant les jeunes a été conçu et mis en oeuvre en Tunisie afin que les ...

  10. Gravity Constraints On The Crustal Structure of Northern Tunisia

    Science.gov (United States)

    Jallouli, Chokri; Mickus, Kevin L.; Turki, Mohamed M.

    Bouguer gravity data were analyzed to determine the general crustal and upper mantle structure in northern Tunisia. Residual gravity anomalies were determined by removing the gravitational effect of crustal thickness variations imaged by regional seismic experiments. Residual gravity anomalies contain short wavelength anomalies superimposed on a long wavelength component that decreases in amplitude northward towards the Tunisian coastline. An edge enhancement analysis (e.g., enhanced analytic signals) of the short wavelength anomalies suggests a previously unknown east-west trending gravity anomaly south of 37°N with source depths between 3 and 7 km. Modeling of the regional, residual and Bouguer gravity anomalies indicate there are two possible solutions for the residual gravity decreasing in northern Tunisia: 1) thickening of Cenozoic and Mesozoic sediments north of a strike-slip faults or 2) a crustal and upper mantle low density zone interpreted to be crustal material of the remnant subducted African plate. The latter result is favored based on seismic tomographic images of the Mediterranean region which implies subducting material exists under the African coast, geologic interpretations suggesting the Tell Atlas may be a thrust wedge accreted by underplating of the African continental crust and seismic refraction models indicating a thinning of sediments in northern Tunisia. The east-west trending gravity anomalies south of 37°N corresponds to an important structural feature that could be either a strike slip/transform fault or the northern edge the African plate.

  11. Water Chemistry in the Confluence Zone Downstream a Limestone Treated Lake and an Acid Tributary: Principal Component Analyses Including Warm and Cold Winters and an Episode High in Sea-Salts

    OpenAIRE

    Andersen, Dag Olav; Christy, Alfred A.

    2010-01-01

    Published version of an article from the journal:International Journal of Arts and Sciences. Also available from the publisher: http://www.openaccesslibrary.org/images/XEW244_Alfred_A._Christy_II_.pdf. Open Access Extensive limestone treatment of lakes and watercourses has been carried out especially in Norway and Sweden to counteract effects of acidification. Lakes have been the most commonly treated part of the water systems. However, treatment of lakes upstream acid tributaries may intr...

  12. Heat Stress in Tunisia: Effects on dairy cows and potential means ...

    African Journals Online (AJOL)

    Tunisia has a Mediterranean climate characterized by high ambient temperatures for a long period. Thus, one of the challenges to dairy producers is heat stress. The objectives of this work were to characterize the environmental conditions to which Holstein cows are exposed in Tunisia using the Temperature Humidity ...

  13. Transitional Justice as Elite Justice? Compromise Justice and Transition in Tunisia

    NARCIS (Netherlands)

    Lamont, Christopher; Pannwitz, Hannah

    2016-01-01

    This article reflects upon the ways in which transitional justice debates and processes impacted Tunisia's transition. It explores key questions such as what demands for justice emerged in the aftermath of the Tunisian revolution? Did Tunisia's transitional justice process reflect these demands?

  14. Great Salt Lake Minerals Source Determination

    Science.gov (United States)

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  15. Salt Lake Cityst Torinoni / Olev Remsu

    Index Scriptorium Estoniae

    Remsu, Olev, 1947-

    2006-01-01

    Dokumentaalfilm Eesti suusameeskonna valmistumisest Torino olümpiamängudeks "Tiim" : idee autorid Peep Puks, Hans Roosipuu : režissöör Peep Puks : F-Seitse 2006. Esilinastus toimus 26. mail Otepääl, ETVs 31. mail

  16. Lake Cadagno

    DEFF Research Database (Denmark)

    Tonolla, Mauro; Storelli, Nicola; Danza, Francesco

    2017-01-01

    Lake Cadagno (26 ha) is a crenogenic meromictic lake located in the Swiss Alps at 1921 m asl with a maximum depth of 21 m. The presence of crystalline rocks and a dolomite vein rich in gypsum in the catchment area makes the lake a typical “sulphuretum ” dominated by coupled carbon and sulphur cyc...

  17. LIMNOLOGY, LAKE BASINS, LAKE WATERS

    Directory of Open Access Journals (Sweden)

    Petre GÂŞTESCU

    2009-06-01

    Full Text Available Limnology is a border discipline between geography, hydrology and biology, and is also closely connected with other sciences, from it borrows research methods. Physical limnology (the geography of lakes, studies lake biotopes, and biological limnology (the biology of lakes, studies lake biocoenoses. The father of limnology is the Swiss scientist F.A. Forel, the author of a three-volume entitled Le Leman: monographie limnologique (1892-1904, which focuses on the geology physics, chemistry and biology of lakes. He was also author of the first textbook of limnology, Handbuch der Seenkunde: allgemeine Limnologie,(1901. Since both the lake biotope and its biohydrocoenosis make up a single whole, the lake and lakes, respectively, represent the most typical systems in nature. They could be called limnosystems (lacustrine ecosystems, a microcosm in itself, as the American biologist St.A. Forbes put it (1887.

  18. Evolutionary dynamics of HBV-D7 subgenotype in Tunisia.

    Science.gov (United States)

    Ciccozzi, Massimo; Chaouch, Houda; Lo Presti, Alessandra; Taffon, Stefania; Villano, Umbertina; Equestre, Michele; Bruni, Roberto; Marcantonio, Cinzia; Tritarelli, Elena; Cella, Eleonora; Blasi, Aletheia; Aouni, Mahjoub; Letaief, Amel; Ciccaglione, Anna Rita

    2017-03-01

    Hepatitis B virus (HBV) is the main cause of diseases liver related infecting more than 200 milion persons worldwide. HBV infection shows high level of prevalence in South-East Europe and in Mediterranean basin. In Tunisia, a country with an intermediate level endemicity, HbsAg prevalence ranges from 2 to 5%. Most of the HBV isolates from Tunisia were classified as subgenotype D7 whose circulation is restricted to a specific area of North Africa including Maghreb region. In this paper, the phylogeny of HBV-D7 isolated from 38 Tunisian patients was investigated by analyzing the S gene region of HBV. A Bayesian coalescent-based framework was used to estimate the origin of the HBV-D7 in the country. The Tunisian D7 isolates were found to share a common ancestor whose origin was traced back to 1958. Population dynamics indicated that HBV-D7 epidemic in Tunisia grew exponentially from 1960s to 1990s. After that, the curve reached a plateau around the years 2000 likely due to the implementation of the infant vaccination program in 1996. Epidemiological data suggested that the exponential growth phase was likely sustained by intra-familial transmission events occurring during infancy. Further characterization of HBV-D7 isolates should be performed to evaluate, in the post-vaccination era, the emergence of new transmission routes, and to monitor the efficacy of the vaccination program. J. Med. Virol. 89:469-475, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  19. Southern Tunisia: A still high endemicity area for hepatitis A.

    Science.gov (United States)

    Neffatti, Houcine; Lebraud, Patricia; Hottelet, Corinne; Gharbi, Jawher; Challouf, Taieb; Roque-Afonso, Anne-Marie

    2017-01-01

    Hepatitis A (HAV) and E (HEV) viruses are responsible for enterically transmitted hepatitis. Tunisia is reported to be of intermediate endemicity for HAV and of low seroprevalence for HEV; however, data from rural areas of South Tunisia are lacking. Sera from 216 asymptomatic pregnant women and from 92 patients with acute hepatitis were collected between October 2014 and November 2015. Total and IgM anti-HAV immunoglobulins and anti-HEV IgG and IgM were investigated. Anti-HAV IgM-positive samples were subjected to RT-PCR targeting the VP1/2A region and sequenced. HEV IgM positive samples and all samples from acute hepatitis patients were assessed for HEV RNA. Among pregnant women (mean age 32+/-8), HAV seroprevalence was 98.6%, none presented anti-HAV IgM; HEV seroprevalence was 5.1% and three presented weakly reactive anti-HEV IgM without detectable RNA. Among acute hepatitis patients (mean age 18.5 +/- 14), HEV seroprevalence was 19,5%, none presented anti-HEV IgM, nor HEV RNA. HAV seroprevalence exceeded 90% by age 5 and acute HAV infection was detected in 20 patients (21,7%), younger than patients with other hepatitis causes (9,8 years vs. 20,4 years, p = 0,004); 65% were male. Most acute HAV infections were observed in a coastal area where HAV infections represented 52% of hepatitis etiology. Phylogenetic analysis identified genotype IA strains, clustering close to previously published Tunisian sequences. The present study confirmed a low HEV endemicity and evidenced a still high level of HAV circulation in Southern Tunisia, suggesting distinct dissemination patterns for these viruses.

  20. Southern Tunisia: A still high endemicity area for hepatitis A.

    Directory of Open Access Journals (Sweden)

    Houcine Neffatti

    Full Text Available Hepatitis A (HAV and E (HEV viruses are responsible for enterically transmitted hepatitis. Tunisia is reported to be of intermediate endemicity for HAV and of low seroprevalence for HEV; however, data from rural areas of South Tunisia are lacking.Sera from 216 asymptomatic pregnant women and from 92 patients with acute hepatitis were collected between October 2014 and November 2015. Total and IgM anti-HAV immunoglobulins and anti-HEV IgG and IgM were investigated. Anti-HAV IgM-positive samples were subjected to RT-PCR targeting the VP1/2A region and sequenced. HEV IgM positive samples and all samples from acute hepatitis patients were assessed for HEV RNA.Among pregnant women (mean age 32+/-8, HAV seroprevalence was 98.6%, none presented anti-HAV IgM; HEV seroprevalence was 5.1% and three presented weakly reactive anti-HEV IgM without detectable RNA. Among acute hepatitis patients (mean age 18.5 +/- 14, HEV seroprevalence was 19,5%, none presented anti-HEV IgM, nor HEV RNA. HAV seroprevalence exceeded 90% by age 5 and acute HAV infection was detected in 20 patients (21,7%, younger than patients with other hepatitis causes (9,8 years vs. 20,4 years, p = 0,004; 65% were male. Most acute HAV infections were observed in a coastal area where HAV infections represented 52% of hepatitis etiology. Phylogenetic analysis identified genotype IA strains, clustering close to previously published Tunisian sequences.The present study confirmed a low HEV endemicity and evidenced a still high level of HAV circulation in Southern Tunisia, suggesting distinct dissemination patterns for these viruses.

  1. Ground observations and remote sensing data for integrated modelisation of water budget in the Merguellil catchment, Tunisia

    Science.gov (United States)

    Mougenot, Bernard

    2016-04-01

    The Mediterranean region is affected by water scarcity. Some countries as Tunisia reached the limit of 550 m3/year/capita due overexploitation of low water resources for irrigation, domestic uses and industry. A lot of programs aim to evaluate strategies to improve water consumption at regional level. In central Tunisia, on the Merguellil catchment, we develop integrated water resources modelisations based on social investigations, ground observations and remote sensing data. The main objective is to close the water budget at regional level and to estimate irrigation and water pumping to test scenarios with endusers. Our works benefit from French, bilateral and European projects (ANR, MISTRALS/SICMed, FP6, FP7…), GMES/GEOLAND-ESA) and also network projects as JECAM and AERONET, where the Merguellil site is a reference. This site has specific characteristics associating irrigated and rainfed crops mixing cereals, market gardening and orchards and will be proposed as a new environmental observing system connected to the OMERE, TENSIFT and OSR systems respectively in Tunisia, Morocco and France. We show here an original and large set of ground and remote sensing data mainly acquired from 2008 to present to be used for calibration/validation of water budget processes and integrated models for present and scenarios: - Ground data: meteorological stations, water budget at local scale: fluxes tower, soil fluxes, soil and surface temperature, soil moisture, drainage, flow, water level in lakes, aquifer, vegetation parameters on selected fieds/month (LAI, height, biomass, yield), land cover: 3 times/year, bare soil roughness, irrigation and pumping estimations, soil texture. - Remote sensing data: remote sensing products from multi-platform (MODIS, SPOT, LANDSAT, ASTER, PLEIADES, ASAR, COSMO-SkyMed, TerraSAR X…), multi-wavelength (solar, micro-wave and thermal) and multi-resolution (0.5 meters to 1 km). Ground observations are used (1) to calibrate soil

  2. Decline of the world's saline lakes

    Science.gov (United States)

    Wurtsbaugh, Wayne A.; Miller, Craig; Null, Sarah E.; Derose, R. Justin; Wilcock, Peter; Hahnenberger, Maura; Howe, Frank; Moore, Johnnie

    2017-11-01

    Many of the world's saline lakes are shrinking at alarming rates, reducing waterbird habitat and economic benefits while threatening human health. Saline lakes are long-term basin-wide integrators of climatic conditions that shrink and grow with natural climatic variation. In contrast, water withdrawals for human use exert a sustained reduction in lake inflows and levels. Quantifying the relative contributions of natural variability and human impacts to lake inflows is needed to preserve these lakes. With a credible water balance, causes of lake decline from water diversions or climate variability can be identified and the inflow needed to maintain lake health can be defined. Without a water balance, natural variability can be an excuse for inaction. Here we describe the decline of several of the world's large saline lakes and use a water balance for Great Salt Lake (USA) to demonstrate that consumptive water use rather than long-term climate change has greatly reduced its size. The inflow needed to maintain bird habitat, support lake-related industries and prevent dust storms that threaten human health and agriculture can be identified and provides the information to evaluate the difficult tradeoffs between direct benefits of consumptive water use and ecosystem services provided by saline lakes.

  3. Determination of hydrologic properties needed to calculate average linear velocity and travel time of ground water in the principal aquifer underlying the southeastern part of Salt Lake Valley, Utah

    Science.gov (United States)

    Freethey, G.W.; Spangler, L.E.; Monheiser, W.J.

    1994-01-01

    A 48-square-mile area in the southeastern part of the Salt Lake Valley, Utah, was studied to determine if generalized information obtained from geologic maps, water-level maps, and drillers' logs could be used to estimate hydraulic conduc- tivity, porosity, and slope of the potentiometric surface: the three properties needed to calculate average linear velocity of ground water. Estimated values of these properties could be used by water- management and regulatory agencies to compute values of average linear velocity, which could be further used to estimate travel time of ground water along selected flow lines, and thus to determine wellhead protection areas around public- supply wells. The methods used to estimate the three properties are based on assumptions about the drillers' descriptions, the depositional history of the sediments, and the boundary con- ditions of the hydrologic system. These assump- tions were based on geologic and hydrologic infor- mation determined from previous investigations. The reliability of the estimated values for hydro- logic properties and average linear velocity depends on the accuracy of these assumptions. Hydraulic conductivity of the principal aquifer was estimated by calculating the thickness- weighted average of values assigned to different drillers' descriptions of material penetrated during the construction of 98 wells. Using these 98 control points, the study area was divided into zones representing approximate hydraulic- conductivity values of 20, 60, 100, 140, 180, 220, and 250 feet per day. This range of values is about the same range of values used in developing a ground-water flow model of the principal aquifer in the early 1980s. Porosity of the principal aquifer was estimated by compiling the range of porosity values determined or estimated during previous investigations of basin-fill sediments, and then using five different values ranging from 15 to 35 percent to delineate zones in the study area that were assumed to

  4. LANDSAT M. S. S. IMAGE MOSAIC OF TUNISIA.

    Science.gov (United States)

    Boswell-Thomas, J. C.; ,

    1984-01-01

    The Landsat mosaic of Tunisia funded by USAID for the Remote Sensing Laboratory, Soils Division, Ministry of Agriculture, Tunisia, was completed by the USGS in September 1983. It is a mixed mosaic associating digital corrections and enhancements to manual mosaicking and corresponding to the Tunisian request for high resolution and the limited available funds. The scenes were processed by the Environmental Research Institute of Michigan, resampling the data geodesically corrected to fit the Universal Transverse Mercator projection using control points from topographic maps at 1:50,000 and 1:100,000 scales available in the U. S. The mosaicking was done in the Eastern Mapping Center under the supervision of the Graphic Arts System Section. The three black and white mosaics were made at the 1:1,000,000 scale and various products generated. They included color film positives at 1:2,000,000 and 1:4,000,000 scales reproducible in the Remote Sensing Laboratory in Tunis and corresponding color prints as well as tricolor prints at various scales from 1:500,000 to 1:2,000,000.

  5. THE ARCHITECTURE OF PUBLIC BATHS OF TUNISIA: A TYPOLOGICAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    Ines Bouraoui

    2008-11-01

    Full Text Available The Punic, Roman, Byzantine and Islamic civilizations contributed with their architectural knowledge to the development of different public baths design. Based on previous historical work on the collective baths in the Mediterranean basin, and in particular Tunisia, this study aims to explore and analyse the hammāms (Islamic public baths of Tunisia. This study uses a semantic and representative approach to help defi ne the components of the historic public bath, and to reveal its integration modes in the urban fabric of the medina, and eventually represent the functional diagrams of bathing practices. It clarifies how the functioning mode of the bath is in direct relation with the evolution of the society (its lifestyle, its culture and its own paradigms and classifi es these building types according to a semantic division of the architectural places. Hence and in order to analyze the hammām spaces, a matrix of incidence. An analytical tool which quantifies the relations existing between the spaces of the same building has been used. As a result of this analysis, three typologies of Tunisian hammāms have been identified.

  6. [Acanthamoeba keratitis. Report of 3 cases diagnosed in central Tunisia].

    Science.gov (United States)

    Fathallah, Akila; Ben Rayana, Narjess; Knani, Leila; Meksi, Sondos Gaied; Saghrouni, Fatma; Ghorbel, Mohamed; Hamida, Fafani Ben Hadj; Ben Said, Moncef

    2010-02-01

    Amoeba of the genus Acanthamoeba are ubiquitous free-living protozoa encountered in water and soil. They frequently cause sight-threatening keratitis. Report of the three first cases diagnosed at the laboratory of Parasitology of Sousse Hospital, (Tunisia). Our study concerned three lens-wearing female patients, aged 17, 20 and 29 years respectively. The patients originate from central Tunisia and presented with unilateral (2 cases) or bilateral (one case) keratitis. Diagnosis was made by demonstrating Acanthamoeba trophozoites and/or cysts on direct examination and/or culture (in agar - Escherichia coli medium) of contact lenses and/or lenses' solution. Direct examination of corneal swabs was negative in three cases but culture was positive in one. The three patients were treated with hexamidine and neomycine eye-drops for three months. Treatment led to scarring of lesions with however sequellar opacities that was minor to moderate in two cases and consisted of a central leucoma with a poor visual outcome in the last case. The need for systematic research of amoeba in lenses wearing patients with keratitis is emphasized.

  7. Irrigated land expansion since 1985 in Southern Tunisia

    Science.gov (United States)

    Rodríguez-Caballero, Emilio; Cantón, Yolanda; Moussa, Mohamed; Solé-Benet, Albert

    2017-05-01

    The causes of agricultural land expansion and its impacts on dryland ecosystems such as the oasis regions of Southern Tunisia, are fundamental problems challenging the sustainability of irrigated agriculture on water limited ecosystems. Consequently, a thorough understanding of this phenomenon is necessary to avoid future problems. With the objective of identifying irrigated land expansion dynamics and the primary drivers, two representative oasis regions in Southern Tunisia, Mareth and Fatnassa, were selected. Changes in irrigated lands in both regions between 1985 and 2011 were analyzed, and the land uses from which expansion occurred were identified using Landsat images from different years (1985, 1996 and 2011). The results indicate that the surface occupied by irrigation agriculture has doubled in Mareth, while in Fatnassa, it has increased fourfold. During that period, there was a simultaneous increase in total population, as consequence of human migration that came along with an increase in income. Thus, we could identify human migration and economic development as potential drivers of irrigated agriculture expansion, though further research is warranted to ascertain a quantification that would assist in obtaining the sustainability of these regions.

  8. Zoonotic Cutaneous Leishmaniasis Prevalence Among Farmers in Central Tunisia, 2014.

    Science.gov (United States)

    Bellali, Hedia; Chemak, Fraj; Nouiri, Issam; Ben Mansour, Dorra; Ghrab, Jamila; Chahed, Mohamed Kouni

    2017-01-01

    Zoonotic cutaneous leishmaniasis (ZCL) is endemic in central Tunisia and is more prevalent in rural agricultural areas. The aim of this work was to determine ZCL prevalence among farmers and to test their availability to take ownership of the problem and participate actively to fight and address the disease. A sample of farmers from Sidi Bouzid, central Tunisia, was selected randomly. Farmers were interviewed using a standardized questionnaire about ZCL lesion occurrence, its date of onset among family members, and the farmers' availability to contribute to fighting this disease. ZCL occurred in at least one of the family members of 38.5% interviewed farmers. The disease was endemic with recurrent epidemics every 4 or 5 years. ZCL among farmers was associated with irrigation management. With regard to ZCL preventive measures, the majority of farmers agreed and expressed willingness to collaborate (93.1%), to follow health care facilities instructions (73.1%), and to join the nongovernmental organization (NGO) (56.9%). However, they did not agree to reduce irrigation activities mainly at night, to live far from their irrigated fields, or to sleep out of their houses at night. ZCL is more prevalent in farmers engaged in irrigation activities. Farmers are not agreeable to reducing their activity to avoid exposure to the sand fly bites. Thus, population involvement and commitment is required to implement effective control measures to fight and address ZCL.

  9. [Mortality due to smoking in Tunisia in 1997].

    Science.gov (United States)

    Fakhfakh, R; Hsairi, M; Ben Romdhane, H; Achour, N

    2001-01-01

    In Tunisia, in spite of the high prevalence of the cigarette smoking among males, there consequences in term of mortality were not until evaluated. These last can be estimated from tobacco consumption data, mortality statistics and estimates of risks observed among populations of smokers in cohort studies. Numbers of deaths by causes have been estimated from WHO for 1998 year. Smoking prevalence have been estimated from a national survey conducted in 1996 by l'Institut National de Santé Publique and the National League against the Tuberculosis and the Respiratory Illness. Mortality attributable to tobacco in Tunisia has been estimated 6430 deaths. The effect of smoking are a lot more important at the man (5580 deaths), contributing to 22% of male deaths, that at the woman (850 deaths) contributing at 4% of the female deaths. The present mortality to tobacco is similar to certain developed countries as France or Canada. The consumption of cigarettes even though it recorded a light decrease during these last years, remain even elevated notably at the young. Then it is waited to see an increase of tobacco related deaths during the future decades. It is urgent to conduct an efficient politics against this tobacco epidemic by helping the smoker to stop smoking and preventing teenagers to begin to smoke.

  10. Sheep pox in Tunisia: Current status and perspectives.

    Science.gov (United States)

    Ben Chehida, F; Ayari-Fakhfakh, E; Caufour, P; Amdouni, J; Nasr, J; Messaoudi, L; Haj Ammar, H; Sghaier, S; Bernard, C; Ghram, A; Cêtre-Sossah, C

    2017-06-28

    Sheep pox, a well-known endemic capripox infection, has significant impacts on small ruminant populations in Tunisia. It is responsible for high economic losses throughout North Africa due to its enzootic nature and to the active animal transhumance existing in some governorates in Tunisia. The aim of this review was to analyse data gathered on annual vaccination campaigns designed to control its spread by reducing the level of endemicity and to describe diagnostic and management tools adapted to the Tunisian situation. Seasonal, temporal and spatial distributions of sheep pox outbreaks, as well as related clinical features, were found. It was concluded from this review that establishing strong herd immunization through individual animal immunization, creating adequate infrastructure, increasing awareness among breeders, setting up a field-based surveillance network and improving routine diagnostic methods need to be the major components of a programme to eradicate the disease. It was also felt that cost-benefit analyses of the surveillance and control strategies used would help in controlling its persistence. © 2017 Blackwell Verlag GmbH.

  11. Technologies for lake restoration

    Directory of Open Access Journals (Sweden)

    Helmut KLAPPER

    2003-09-01

    Full Text Available Lakes are suffering from different stress factors and need to be restored using different approaches. The eutrophication remains as the main water quality management problem for inland waters: both lakes and reservoirs. The way to curb the degradation is to stop the nutrient sources and to accelerate the restoration with help of in-lake technologies. Especially lakes with a long retention time need (eco- technological help to decrease the nutrient content in the free water. The microbial and other organic matter from sewage and other autochthonous biomasses, causes oxygen depletion, which has many adverse effects. In less developed countries big reservoirs function as sewage treatment plants. Natural aeration solves problems only partly and many pollutants tend to accumulate in the sediments. The acidification by acid rain and by pyrite oxidation has to be controlled by acid neutralizing technologies. Addition of alkaline chemicals is useful only for soft waters, and technologies for (microbial alkalinization of very acidic hardwater mining lakes are in development. The corrective measures differ from those in use for eutrophication control. The salinization and water shortage mostly occurs if more water is used than available. L. Aral, L. Tschad, the Dead Sea or L. Nasser belong to waters with most severe environmental problems on a global scale. Their hydrologic regime needs to be evaluated. The inflow of salt water at the bottom of some mining lakes adds to stability of stratification, and thus accumulation of hydrogen sulphide in the monimolimnion of the meromictic lakes. Destratification, which is the most used technology, is only restricted applicable because of the dangerous concentrations of the byproducts of biological degradation. The contamination of lakes with hazardous substances from industry and agriculture require different restoration technologies, including subhydric isolation and storage, addition of nutrients for better self

  12. Makgadikgadi Salt Pan, Botswana, Africa

    Science.gov (United States)

    1992-01-01

    The Makgadikgadi Salt Pan of Botswana, an ancient lake bed, (19.0S, 26.0E) is one of the largest features in Botswana visible from orbit. Any water that spills out of the Okavango Swamplands flows into the Makagadikgadi where it evaporates. An ancient beach line can be seen as a smooth line around the west side of the pan and to the south, the Orapa diamond mine is seen as a small rectangle. Far to the east, can be seen the Great Dike of Zimbabwe.

  13. Impacts of wastewater irrigation in arid and semi arid regions: case of Sidi Abid region, Tunisia

    Science.gov (United States)

    Bouri, Salem; Abida, Habib; Khanfir, Hafedh

    2008-02-01

    Impacts of irrigation with treated wastewater effluents on soils and groundwater aquifer in the vicinity of Sidi Abid Region (Tunisia) are evaluated. The groundwater aquifer was monitored by several piezometers, where monthly water levels were registered and groundwater salinity was evaluated. This resulted in characterizing the spatial and temporal evolution of the hydrochemical and hydrodynamic properties of the aquifer, showing thereby the impact of artificial recharge. Piezometric maps for pre-recharge and post-recharge situations were developed and a comparison study of both piezometric situations was considered. The piezometric evolution map showed a generalized rise of the piezometric level in the vicinity of the irrigation zone. The extent of recharge was shown to increase with time as the groundwater level increase, which was localized in the vicinity of the irrigation area, reached more extended zones. Several groundwater samples were withdrawn from wells and piezometers and analyzed. Examining the corresponding physical and chemical parameters showed an increase in the concentrations of nutrients (28 mg/l for NO3 and 3.97 mg/l for NH4) in the groundwater aquifer below the irrigation zone, which confirms again the infiltration of treated wastewater effluents. The evolution of soil salinity was examined through chemical analysis of soil samples. Electric conductivities of soils were generally shown to be less than 4 mS/cm while the irrigation water has an electric conductivity that may reach 6.63 mS/cm. This might be explained by the phenomenon of dilution and the capacity of soils to evacuate salts downward.

  14. Isolation and identification of phenol degrading bacteria from Lake ...

    African Journals Online (AJOL)

    The aim of this study is to isolate and identify phenol degrading bacteria from Lake Parishan and to assay their kinetic growth. Sixty samples of water and sedimentation of different area of Lake Parishan were collected. In order to isolate phenol degrading bacteria, samples were cultured on salt base phenol broth media.

  15. Past, present and future of saline lakes: research for global sustainable development

    Science.gov (United States)

    Shadrin, Nickolai; Zheng, Mianping; Oren, Aharon

    2015-11-01

    The 12th International Conference on Salt Lake Research was held in Langfang City, China from July 14 to 18, 2014. Fifteen manuscripts of presentations have been retained for publication in this special issue. They are very diverse, covering the biology, physics, chemistry and geology of salt lakes, the history of hydrological research on the Dead Sea, the effects of socioeconomic and environmental policies by stakeholders on human populations, and the increasing salinization of freshwater lakes around the world.

  16. Update of “Biodiversity of the Hypersaline Urmia Lake National Park (NW Iran”

    Directory of Open Access Journals (Sweden)

    Alireza Asem

    2016-03-01

    Full Text Available Urmia Lake, an endorheic salt lake in northwestern Iran, was registered in the Ramsar Convention on Wetlands as a wetland of international importance, also a UNESCO biosphere reserve. In this review, we have updated our last checklist in 2014 with available information on the biodiversity of the lake.

  17. Sustainability of irrigated agriculture under salinity pressure – A study in semiarid Tunisia

    OpenAIRE

    Bouksila, Fethi

    2011-01-01

    In semiarid and arid Tunisia, water quality and agricultural practices are the major contributing factors to the degradation of soil resources threatening the sustainability of irrigation systems and agricultural productivity. Nowadays, about 50% of the total irrigated areas in Tunisia are considered at high risk for salinization. The aim of this thesis was to study soil management and salinity relationships in order to assure sustainable irrigated agriculture in areas under salin...

  18. First report of olive anthracnose caused by Colletotrichum gloeosporioides in Tunisia

    Directory of Open Access Journals (Sweden)

    Ali Rhouma

    2010-05-01

    Full Text Available Ripe and overripe olive fruits (cv. Meski, Manzanilla and Picholine showing circular spots 1 to 10 mm in diameter, slightly depressed and reddish-brown in color, were collected from local markets and orchards located in the regions of Takelsa, Zarzis and Rgueb in Tunisia. Colletotrichum gloeosporioides was isolated from symptomatic fruits and Koch’s postulates were fulfilled. This is the first report of Colletotrichum gloeosporioides causing anthracnose of olives in Tunisia.

  19. Suicide Among Adolescents in Center Tunisia: An 18-Year Autopsy Study

    OpenAIRE

    Jedidi M; Mlayeh S; Hamila I; Masmoudi T; Ben Dhiab M; Zemni M; Souguir MK

    2016-01-01

    Background: Suicide and suicide attempts are more common among adolescents. Many factors are known to influence suicide in particular: region and culture. Adolescent suicide has been widely studied in many countries, but there are, currently, no data relating to adolescent suicide in Tunisia. Aim: The aims of this study were to describe epidemiological aspects of death related to adolescent suicide in Sousse, a city in central Tunisia. Methods: Data of forensic autopsies from 1998 to 2015 rel...

  20. Association among Education Level, Occupation Status, and Consanguinity in Tunisia and Croatia

    OpenAIRE

    Kerkeni, Emna; Monastiri, Kamel; Saket, Besma; Rudan, Diana; Zgaga, Lina; Ben Cheikh, Hassen

    2006-01-01

    Aim: To investigate the association between education level, occupation status (a proxy for socio-economic status), and consanguinity in 2 large data sets from Tunisia and Croatia countries with different attitudes toward consanguinity. Methods: The sample of 1016 students, attending 5 university institutions in Monastir, Tunisia, were interviewed about the educational level and occupation status of their parents and the degree of parental relatedness. In Croatia, a sample of 1001 examinee...

  1. Market Power and Collusion on Interconnection Phone Market in Tunisia: What Lessons from International Experiences

    OpenAIRE

    Sami DEBBICHI; Walid HICHRI

    2014-01-01

    We try in this paper to characterize the state of mobile phone market in Tunisia. Our study is based on a survey of foreign experience (Europe) in detecting collusive behavior and a comparison of the critical threshold of collusion between operators in developing countries like Tunisia. The market power is estimated based on the work of Parker Roller (1997) and the assumption of "Balanced Calling Pattern". We use then the model of Friedman (1971) to compare the critical threshold of collusion...

  2. Civil liberties in Tunisia following the 2011 uprisings

    Directory of Open Access Journals (Sweden)

    Carmelo Pérez Beltrán

    2015-05-01

    Full Text Available This article analyses the legislative changes made in relation to civil liberties in Tunisia since the 2011 revolts, specifically, those concerned with freedom of association, expression, and regulation of the media and links them to the socio-political context of the country. The paper intends to demonstrate how social and political factors have produced a new legal framework of action that is based on the new constitution, but which also brings intense regulatory development that in many respects breaks with previous legislation, although certain elements of authority inherited from the past have been preserved. Two aspects deserve special consideration: on the one hand these rules maintain certain limitations as means of social control that are not totally consistent with a developed democracy; and, on the other, problems of interpretation, cultural specificity and authoritarian behaviour mean the lack of liberties in such fundamental areas as those analysed are also preserved.

  3. A new species of Mengenilla (Insecta, Strepsiptera from Tunisia

    Directory of Open Access Journals (Sweden)

    Hans Pohl

    2012-05-01

    Full Text Available A new species of Mengenilla Hofeneder, 1910 (Strepsiptera, Mengenillidae from southern Tunisia is described. Mengenilla moldrzyki sp. n. can be distinguished from congeners by a slightly emarginated posterodorsal margin of the head, compound eyes with a light tan dorsal part, mandibles with a narrow distal part, and a v-shaped pronotum. With the description of M. moldrzyki sp. n., eleven valid species of Mengenilla are currently recognised. Mengenilla moldrzyki sp. n. is the third species of the genus with known females and female puparia. First instar larvae, endoparasitic larval stages, the male puparium and the host are unknown. The new species is also the first strepsipteran with a fully sequenced genome.

  4. Preliminary study of plants used in ethnoveterinary medicine in Tunisia and in Italy.

    Science.gov (United States)

    Viegi, Lucia; Ghedira, Kamel

    2014-01-01

    A survey relative to the use of plants for the cure of animals in Tunisia was conducted in order to make a comparison with the same species (or similar ones) in central and southern Italy. available bibliographical data both for Italy and for Tunisia were consulted. Thirty-nine plants, representing 22 families, used in Tunisia in ethnoveterinary medicine were reported, and comparisons made with close species used in Central and Southern Italy. Seven of the 39 species (about the 18% of the total) are not present in Italian flora. Fourteen of the 39 species (35% of the total) are also used in Italy. Camelidae (dromedaries and camels) are the most valuable types of domestic animals cured in Tunisia, but ovines, horses, bulls, dogs are also treated. Some uses coincide with those existing in different Italian regions. The plants used are the most common and most easily found in these areas. The present study confirms the convergence in ethnoveterinary medicine between Tunisia and Italy, even if it appears less significant than in human ethnobotany. Further studies are required in areas of Tunisia that have not yet been studied, in order to get the possibility of an evaluation of active compounds.

  5. Groundwater salinization survey of the Upper Cretaceous-Miocene Complexe terminal aquifer in the Sabaa Biar area of southwestern Tunisia

    Science.gov (United States)

    Mhamdi, Abdelkader; Dhahri, Ferid; Gouasmia, Mouez; Moumni, Lahmadi; Mohamed, Soussi

    2015-12-01

    An integrated hydrogeological study involving the Schlumberger depth sounding method, geological data and wells data was conducted at the Sabaa Biar area of southern Tunisia to elucidate the problem of increasing groundwater salinity within The ;Complexe Terminal;. The ;Complexe Terminal; aquifer near Sabaa Biar region is a bi-layered aquifer comprised of fractured limestones of the Cretaceous (Campanian-Maastrichtian) Berda Formation and sandstone of the Miocene Beglia Formation. The aquifer is affected by a main NW-trending fault, which is a chemical barrier that divides the study area into eastern and western blocks delivering freshwater and saline water, respectively. The salinization of groundwater within the limestone (Campanian-Maastrichtian Berda Formation) is linked mainly to the dissolution of outcropping Coniacian-Santonian gypsum along the core of the Jebel Sidi Bouhlel anticline to the east of the study area. Meteoric water dissolves salt from outcropping gypsum, flows through the fractures networks, and recharges the fractured limestone of the upper Berda Formation. The mobilization of salts stored in the salt-rich Quaternary sediment on hillslopes and inchannels contributes also to the salinization of groundwater within the sandstone (Miocene Beglia Formation) by lateral infiltration subsequent to water drainage during the wet season. The over exploitation of water from the Miocene sandstone causes an influx of saline-rich water from the underlying limestone of the Berda Formation into the sandstone of the Beglia Formation. Other sources of salinization of groundwater (such as ascension of hypersaline water from deep aquifer along faults, and the return flow of irrigation waters in the Djerid region) have been documented in this region, but are not discussed in this paper.

  6. Fairness in healthcare finance and delivery: what about Tunisia?

    Science.gov (United States)

    Abu-Zaineh, Mohammad; Arfa, Chokri; Ventelou, Bruno; Ben Romdhane, Habiba; Moatti, Jean-Paul

    2014-07-01

    Anecdotal evidence on hidden inequity in health care in North African countries abounds. Yet firm empirical evidence has been harder to come by. This article fills the gap. It presents the first analysis of equity in the healthcare system using the particular case of Tunisia. Analyses are based on an unusually rich source of data taken from the Tunisian HealthCare Utilization and Morbidity Survey. Payments for health care are derived from the total amount of healthcare spending which was incurred by households over the last year. Utilization of health care is measured by the number of physical units of two types of services: outpatient and inpatient. The measurement of need for health care is apprehended through a rich set of ill-health indicators and demographics. Findings are presented and compared at both the aggregate level, using the general summary index approach, and the disaggregate level, using the distribution-free stochastic dominance approach. The overall picture is that direct out-of-pocket payments, which constitute a sizeable share in the current financing mix, emerge to be a progressive means of financing health care overall. Interestingly, however, when statistical testing is applied at the disaggregate level progressivity is retained over the top half of the distribution. Further analyses of the distributions of need for--and utilization of--two types of health care--outpatient and inpatient--reveal that the observed progressivity is rather an outcome of the heavy use, but not need, for health care at the higher income levels. Several policy relevant factors are discussed, and some recommendations are advanced for future reforms of the health care in Tunisia. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine © The Author 2013; all rights reserved.

  7. [Neonatal screening of G6PD deficiency in Tunisia].

    Science.gov (United States)

    Guellouz, N; Ben Mansour, I; Ouederni, M; Jabnoun, S; Kacem, S; Mokrani, Ch; Kastally, R; Chahed, M K; Khrouf, N

    2010-01-01

    The Glucose-6-phosphate dehydrogenase (G6PI) deficiency is the most common enzymopathy worldwide. WHO had classified Tunisia among countries that are moderately affected by this affection. However, no mass-screening reflecting the real incidence was realized. The aim of this study is to determine the prevalence of this enzymopathy and its molecular basis in Tunisia. A total of 1102 neonates, born in CMNT center of Maternity and of Neonatology of Tunis during the going periods from April, 2005 till May, 2005 and from June, 2006 till September, 2006, have been enclosed in the study. The samplings included 953peripheral venous blood and 149 blood cordon. Among 1102 samplings, only 976 were of use to the screening. In our mass-screening, we consider all newborns that were born in the CMNT during the period of study and were included in the screening. A dosage of the enzymatic activity was realized using spectrophotometric method. G6PD electrophoresis and molecular study by PCR/RFLP were realized for the overdrawn newborn children. Among 976 screening neonates, 43 individuals (4.4%) were found to be G6PD deficient by quantitative enzyme assay. Newborn affected were distributed in 23 boys and 20 girls (sex ratio of 1.15). The electrophoretic mobility and the molecular biology were realized for the affected newborn. Molecular characterization of 30 G6PD deficient neonates revealed that the G6PD A- was the most common and was detected in 20 of 43 individuals (66.7%), followed by G6PD Mediterranean that was detected in 6 (13.3%). At least, 4 other unknown mutations were not able to be determined by PCR/RFLP (n=4). In conclusion G6PD deficiency is frequent in our country, justifying a systematic neonatal screening, to avoid the arisen of grave consequences of this affection. The African variant is the most frequent in our country followed by the Mediterranean one.

  8. Intestinal helminths of golden jackals and red foxes from Tunisia.

    Science.gov (United States)

    Lahmar, Samia; Boufana, Belgees; Ben Boubaker, Sarra; Landolsi, Faouzi

    2014-08-29

    Forty wild canids including 31 golden jackals (Canis aureus Linné, 1758) and 9 red foxes (Vulpes vulpes Linné, 1758) collected between 2008 and 2011 in the northeast, northwest and center of Tunisia were necropsied and examined for intestinal helminth parasites. All jackals and foxes were found infected with a prevalence rate of 95% for cestodes, 82.5% for nematodes and 7.5% for acanthocephalans. A total of twelve helminth species were recorded in red foxes: cestodes, Dipylidium caninum (55.6%), Diplopylidium noelleri (55.6%), Mesocestoïdes lineatus (55.6%), Mesocestoïdes litteratus (33%), Mesocestoïdes corti (22%); nematodes, Ancylostoma caninum (11%), Uncinaria stenocephala (44%), Spirura rytipleurites (11%), Trichuris vulpis (33%), Pterygodermatites affinis (67%), Oxynema linstowi (33%) and the acanthocephalan Macracanthorhynchus hirudinaceus (22%). The fifteen recovered helminth species in jackals were Echinococcus granulosus (9.7%), D. caninum (16%), D. noelleri (16%), M. lineatus (74%), M. litteratus (23%), M. corti (12.9%), Taenia pisiformis (3.2%), Taenia spp. (19%), Toxocara canis (16%), Toxascaris leonina (6.5%), A. caninum (9.7%), U. stenocephala (68%), P. affinis (6.5%), O. linstowi (3.2%) and Macracanthorhynchus hirudinaceus (3.2%). This is the first report on the presence of P. affinis, D. noelleri and O. linstowi in Tunisia. E. granulosus was found in young jackals, aged less than 4 years old, with a higher abundance in females (8.9 worms). M. lineatus presented the highest mean intensity of 231.86 and 108.8 tapeworms respectively in jackals and foxes. Canids from the northwest region had the highest prevalence (77.5%) and highest intensity (243.7) of helminth species compared to those from the northeast and central areas. U. stenocephala and O. linstowi had the highest mean intensity for nematodes in both jackals and foxes at 14.3 and 88 worms respectively. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Coniacian-Turonian Carbonates of the Miskar Field, offshore Tunisia

    Energy Technology Data Exchange (ETDEWEB)

    Knott, I. [Gas Exploration & Prod. Ltd., Reading Berkshire (United Kingdom); Moody, R. [Kingston Univ., Surrey (United Kingdom); Sandman, R. [Hedge End, Hampshire (United Kingdom)

    1995-08-01

    The R1 and R1 Superior Carbonates of the Miskar Field, offshore Tunisia are of Coniacian-Turonian age. These ages are constrained by several biostratigraphic events including a rapid increase in ostracod diversity at the base of the overlying Aleg Formation and the occurrence of several diagnostic benthonic foraminifera including Rotalia algeriana. The indication is that the R1 and R1 Superior Carbonates are the lateral equivalents, in part, of the Douleb Formation which is a known reservoir, onshore Tunisia. During the Coniacian-Turonian the area of the Miskar Field was subject to regional extension with the opening of several major North-South trending fractures. These culminate in the contemporaneous outpouring of submarine serpentinized volcanics during deposition of the R1 Superior/Aleg Formation. The R1 lithologies are deposited in a shallow water regime and consist of rudist buildup and debraic carbonates overlain by lagoonal facies in the North with an increase in beach/sabkha facies to the South. The indication is for a shallowing upward sequence and a general progradation of lithofacies northwards across a tilted block. In contrast the R1 Superior is indicative of a flooding event with relative sea-level changes reflected in variations of both lithofacies and biofacies. Overall the lithofacies are dominated by calcispheric/bioclastic wackestone-packstones probably deposited in a mid-platform setting. The diagenetic history of the R1 is the more complex of the two carbonate sequences reflecting several phases of fluid movement through the constituent lithologies. Original depositional characteristics and subsequent diagenetic meditation result in the development of highly variable reservoir properties.

  10. Celestial Navigation in the USA, Fiji, and Tunisia

    Science.gov (United States)

    Holbrook, Jarita C.

    2015-05-01

    Today there are many coastal communities that are home to navigators who use stars for position finding at night; I was, however, unaware of this fact when I began researching celestial navigation practices in 1997. My project focused on three communities: the Moce Islanders of Fiji, the Kerkennah Islanders in Tunisia, and the U.S. Navy officers and students at the United States Naval Academy, Annapolis, Maryland. My goal was to answer the question of why people continue to navigate by the stars, but also to understand the role of technology in their navigation practices. Using anthropology techniques of ethnography including participant observation, formal and informal interviews, audio and videotaping, I gathered data over five years at the three communities. I began by learning the details of how they use the stars for navigation. Next, I learned about who did the navigation and where they learned to navigate. I gathered opinions on various navigation aids and instruments, and opinions about the future of using the stars for navigation. I listened to the stories that they told about navigating. In the United States I worked in English, in Fiji, in Fijian and English, and in Tunisia, French and English. For the formal interviews I worked with translators. The navigators use stars for navigating today but the future of their techniques is not certain. Though practiced today, these celestial navigation traditions have undergone and continue to undergo changes. New navigational technologies are part of the stimulation for change, thus 'a meeting of different worlds' is symbolized by peoples encounters with these technologies.

  11. Playa Lakes

    Data.gov (United States)

    Kansas Data Access and Support Center — This digital dataset provides information about the spatial distribution of soil units associated with playa lakes. Specific soil types have been designated by the...

  12. White Lake AOC

    Science.gov (United States)

    White Lake is in Muskegon County along the eastern shore of Lake Michigan. It was named an Area of Concern on the Great Lakes under the Great Lakes Water Quality Agreement of 1987 and delisted in 2014.

  13. Study of variation in groundwater quality in a coastal aquifer in north-eastern Tunisia using multivariate factor analysis

    KAUST Repository

    Charfi, Sihem

    2013-07-01

    This work focuses on the Grombalia aquifer which constitutes the main water resource in Northeast Tunisia, Cap Bon Peninsula. The recharge of this aquifer is ensured mainly by direct infiltration of rainwater through permeable layers. Under semi-arid climatic conditions and increasing water demand for irrigation, about 80% of the Grombalia aquifer system shows different vulnerabilities to anthropogenic activities. The total dissolved solids values range from 0.75 to 5.6g/l.Isotopic characterization with stable isotopes (δ2H and δ18O) of Grombalia aquifer system identified geochemistry processes that control water chemistry. In addition, the multivariate statistical technique (Principal Component Analysis) was used to identify the origin, the recharge mode and geochemical processes controlling groundwater quality. The principal reactions responsible for the hydrochemical evolution in the Grombalia groundwater fall into three categories: (1) denitrification process; (2) dissolution of salts; and (3) irrigation return flow process. Tritium data in groundwater from the study area suggest the existence of pre1950 and post1960 recharge. © 2012 Elsevier Ltd and INQUA.

  14. Composition and distribution of planktonic ciliates from ponds of different salinity in the solar saltwork of Sfax, Tunisia

    Science.gov (United States)

    Elloumi, Jannet; Carrias, Jean-François; Ayadi, Habib; Sime-Ngando, Télesphore; Boukhris, Mekki; Bouaïn, Abderrahmen

    2006-03-01

    The planktonic ciliated protozoa of 14 ponds of increasing salinity were investigated in the saline of Sfax, Tunisia. Taxa of the classes of Spirotrichea and Heterotrichea were the numerous ciliates. Abundance of the community ranged from 0.0 to 11.8 × 10 4 ciliates per litre. Values decrease significantly with salinity gradient, as species richness does. Based on the range of salinity over which ciliate taxa appeared, we distinguished three groups of ciliates. The first group is mainly composed of oligotrichs and choreotrichs that are commonly found in marine coastal waters. Small ciliates belonging to the order Prostomatida were found in a large range of salinity values, but their densities also decreased with salt concentration. In contrast, large-size species of heterotrichous ciliates were found in ponds with high salinity values only. In these ponds, the presence of prey appeared as an important factor in controlling the abundances of these halotolerant ciliates. Our data also suggest that Fabrea salina, a common halophile ciliate, acts as a competitor of the brine shrimp Artemia salina in the saline of Sfax. Salinity, prey availability, and the presence of competitors seem to be the main factors for the distribution of ciliate taxa in this hypersaline environment.

  15. Assessing the hydrological impacts of agricultural changes upstream of the Tunisian World Heritage sea-connected Ichkeul Lake

    Directory of Open Access Journals (Sweden)

    J. Aouissi

    2015-03-01

    Full Text Available The impact of changes in agricultural land use and practices as a controlling driver of hydrologic response and as a source of diffuse pollution, are studied in the Joumine River basin, discharging into the Ichkeul Lake, northern Tunisia, a UNESCO World Heritage site since 1979. The lake is characterized by a very specific hydrological functioning based on a seasonal alternation of water levels and salinity through its link to the Mediterranean Sea. Three Landsat images, in situ surveys and SWAT modelling were used to simulate and assess streamflows and nitrate loads under retrospective land uses.

  16. Salt on roads and the environment (VB)

    DEFF Research Database (Denmark)

    Hessberg, Philipp von; Jørgensen, Michael Søgaard

    2000-01-01

    This report descripes the extent of use of salt on roads in Denmark and the environmental consequences of this. Alternative strategies for reducing the risk of greasy roads and different ways of alleviating the vegetation are also discussed.The different consequences for the environment that this...... that this report discusses are:- The ground water.- Lakes and streams.- Plants and trees along roads.The consequences for the economy through usage of salt on roads has not been carried out.......This report descripes the extent of use of salt on roads in Denmark and the environmental consequences of this. Alternative strategies for reducing the risk of greasy roads and different ways of alleviating the vegetation are also discussed.The different consequences for the environment...

  17. [Anatomopathological profile of breast cancer in cape bon, Tunisia].

    Science.gov (United States)

    Sahraoui, Ghada; Khanchel, Fatma; Chelbi, Emna

    2017-01-01

    Breast cancer is the most common cancer among tunisian women and worldwide. In Cape Bon, Tunisia, the anatomopathological features of this cancer have not been established in previously published studies. Knowledge about these features is needed for the cultural adaptation of prevention and health care systems in the region. The aim of our study was to determine the pathological profile of breast cancers in the only public health anatomic pathology regional laboratory. We conducted a retrospective descriptive study of 116 patients who were diagnosed with breast cancers in our laboratory over a 5-year period, from July 2010 to July 2015. Our study included 116 patients. The average age was 51 years. The mean histologic tumor size was 31 mm. The initial diagnosis was based on lumpectomy in 83% of the cases. Nonspecific invasive cancer was the most frequent histological type. SBR grade III was most prevalent. Lymphovascular invasion was detected in 33% of cases. Axillary lymph node dissection was performed in 72% of cases. Hormone receptors were positive in 73% of cases. Her2-Neu receptors were overexpressed in 19% of cases. The ki67 was ≥ 14% in 38% of cases. Luminal A was the most common molecular subtype. In Cap Bon region brest cancer is characterized by an early onset, a large tumor size and pejorative histoprognostic factors.

  18. [Hereditary ichthyosis in Tunisia: epidemiological study of 60 cases].

    Science.gov (United States)

    Kharfi, Monia; El Fekih, Nadia; Ammar, Donia; Khaled, Aida; Fazaa, Bécima; Ridha Kamoun, Mohamed

    2008-11-01

    Ichthyosis are a group of inherited keratinizing disorders. The cutaneous abnormalities may be isolated or associated with extra-cutaneous symptoms. To report the epidemiological and clinical profiles of patients with these genodermatoses from a hospital tunisian study. A retrospective study of all cases of ichthyosis referred during a period of 5 years to the department of dermatology of Charles Nicole's hospital of Tunis. Sixty cases of hereditary ichthyosis were seen. The sex-ratio was of 0.5. Parental consanguinity was noted in 36 patients (60%). Seventeen patients (25.7%) had a positive familial history of ichthyosis. The clinical form of ichthyosis was determined in 52 cases. The nonbullous ichthyosiform erythroderma was observed in 25 patients (41.6%). Sixty patients presented an ichthyosis vulgaris (26.6%). The other forms of ichthyosis were rarely observed : 4 cases of X-linked recessive ichthyosis, 2 cases of lamellar ichthyosis and 2 cases of bullous ichthyosiform erythroderma. Two patients were born with collodion-like membranes. Two cases presented a complex syndrome. The NBIE, commonly considered as a rare form of ichthyosis, was the most frequently form seen in our study (41.6%), probably because of the high frequency of consanguineous marriages in Tunisia. The IV represents the most frequent form reported in the literature and was observed in 25% of our patients. The classification of some ichthyosis associated with other extracutaneous abnormalities (found in 2 of our patients) remains difficult.

  19. Reuse of reclaimed wastewater for golf course irrigation in Tunisia.

    Science.gov (United States)

    Bahri, A; Basset, C; Oueslati, F; Brissaud, F

    2001-01-01

    In Tunisia, golf courses are irrigated with secondary treated effluent stored in landscape impoundments. The impact of the conveyance and storage steps on the physical-chemical and biological quality of irrigation water was evaluated on three golf courses over two years. It was found that the water quality varies all along the water route, from the wastewater treatment plant up to the irrigation site: nutrient and bacteria contents decreased along the route in the three cases. This variation depends on the wastewater quality, the length of the pipes conveying water, the number of regulation reservoirs and ponds, the water residence time in pipes, reservoirs and ponds, and the operation of the ponds. The bacteriological quality of irrigation water deteriorates during the irrigation period in the three golf courses as the ponds are operated as continuous flow reactors. The results obtained in this study indicate the inability of golf water supplies, as currently managed, to properly sanitize reclaimed wastewater and meet target quality criteria recommended by WHO (1989) for water intended for recreational use. For a safe reuse of reclaimed wastewater for golf course irrigation, changes in the design and operation of the ponds should be planned or additional treatment steps provided.

  20. Risk assessment of fluoride exposure in drinking water of Tunisia.

    Science.gov (United States)

    Guissouma, Wiem; Hakami, Othman; Al-Rajab, Abdul Jabbar; Tarhouni, Jamila

    2017-06-01

    The presence of fluoride in drinking water is known to reduce dental cavities among consumers, but an excessive intake of this anion might leads to dental and skeletal fluorosis. This study reports a complete survey of the fluoridated tap water taken from 100 water consumption points in Tunisia. The fluoride concentrations in tap water were between 0 and 2.4 mg L(-1). Risk assessment of Fluoride exposure was assessed depending on the age of consumers using a four-step method: hazard identification, toxicity reference values selection (TRVs), daily exposure assessment, and risk characterization. Our findings suggest that approximately 75% of the Tunisian population is at risk for dental decay, 25% have a potential dental fluorosis risk, and 20% might have a skeletal fluorosis risk according to the limits of fluoride in drinking water recommended by WHO. More investigations are recommended to assess the exposure risk of fluoride in other sources of drinking water such as bottled water. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. [Histologic and prognostic study of nephroblastoma in central Tunisia].

    Science.gov (United States)

    Amel, L; Leila, B F; Lamia, K; Olfa, G; Abdelfattah, Z; Mondher, G; Faouzi, M; Chakib, K; Abdelatif, N; Amor, G; Slim, B A

    2003-08-01

    Nephroblastoma is a common malignant tumour in childhood that benefited from therapeutic progress. This is a retrospective study of 35 nephroblastoma diagnosed and treated in the central region of Tunisia within the last 8 years (1991-1999). We report and compare clinical features, therapeutic results and prognostic factors with those reported in the literature. The mean age was 3-years and 9 months, and the main clinical symptom was abdominal mass. Pre-operative chemotherapy was done in 32 cases and the objective response rate was 58%. Thirty-three patients had radical nephrectomy and only one had partial nephrectomy. Histologic analysis concluded to an anaplastic nephroblastoma in 2 cases. Using the classification of the international society of pediatric oncology, 11.4% of tumours were stage I, 48.6% stage II, 5.7% stage III, 11.4% stage IV and 2.9% stage V. The overall 5 years survival was 80%; tumour relapse was only independent prognosis factor in multivariate analysis (P < 0.01). Prognosis of nephroblastoma has been improved with chemotherapy and the pluridisciplinar treatment.

  2. The "Continental Intercalaire" of southern Tunisia: Stratigraphy, paleontology, and paleoecology

    Science.gov (United States)

    Fanti, Federico; Contessi, Michela; Franchi, Fulvio

    2012-09-01

    The "Continental Intercalaire" deposits of southern Tunisia preserve one of the most diverse Early Cretaceous vertebrate fauna from Africa, consisting of elasmobranchs, actinopterygians, sarcopterygians, turtles, crocodyliforms, pterosaurs, and non-avian dinosaurs. Vertebrate remains representative of both marine and fluvial environments have been historically referred to a specific bonebed within the Chenini Member, which crops out extensively in the Tataouine region. A stratigraphic revision of the mainly siliciclastic deposits of the Douiret and the Aïn El Guettar formations in the area based on new sedimentological and paleontological data is presented. Data collected indicate the presence of multiple fossil-bearing strata encompassing the stratigraphic interval from the Berriasian to the Albian and document faunal variation through time as well as major environmental and climatic changes. Detailed sedimentological analysis combined with biostratigraphic correlation performed at a basin scale indicate lateral facies variability within each formation as a result of tectonically and climatically driven zonations within the Tataouine Basin in the Early Cretaceous. Furthermore, proposed stratigraphic correlations indicate that vertebrate remains previously referred to the fluvial Chenini Member (and in particular theropod and sauropod dinosaurs) are instead representative of a transgressive deposit which mark the base of the overlying Oum ed Diab Member.

  3. Digenean species diversity in teleost fishes from the Gulf of Gabes, Tunisia (Western Mediterranean).

    Science.gov (United States)

    Derbel, H; Châari, M; Neifar, L

    2012-05-01

    This study is the first attempt to survey the diversity of fish digeneans in the Gulf of Gabes (southern coast of Tunisia). A total of 779 fishes belonging to 32 species were sampled. 53 species of Digenea belonging to 15 families were recorded. Among these species, 24 are reported for the first time from the coast of Tunisia. We report one new host record, Lecithochirium sp. from Sardinella aurita. The Hemiuridae is the dominant family. A host-parasite list is presented with the information on the prevalence, abundance and mean intensity of each species collected. The diversity of Digenea is compared with other localities in the Mediterranean Sea and the northern east of Tunisia. The Gulf of Gabes shows the lowest diversity linked to the anthropogenic activities and impact of exotic species. The use of Digenea as indicators of the state of the ecosystem is discussed.

  4. Digenean species diversity in teleost fishes from the Gulf of Gabes, Tunisia (Western Mediterranean

    Directory of Open Access Journals (Sweden)

    Derbel H.

    2012-05-01

    Full Text Available This study is the first attempt to survey the diversity of fish digeneans in the Gulf of Gabes (southern coast of Tunisia. A total of 779 fishes belonging to 32 species were sampled. 53 species of Digenea belonging to 15 families were recorded. Among these species, 24 are reported for the first time from the coast of Tunisia. We report one new host record, Lecithochirium sp. from Sardinella aurita. The Hemiuridae is the dominant family. A host-parasite list is presented with the information on the prevalence, abundance and mean intensity of each species collected. The diversity of Digenea is compared with other localities in the Mediterranean Sea and the northern east of Tunisia. The Gulf of Gabes shows the lowest diversity linked to the anthropogenic activities and impact of exotic species. The use of Digenea as indicators of the state of the ecosystem is discussed.

  5. First survey on ecological host range of aphid pathogenic fungi (Phylum Entomophthoromycota) in Tunisia

    DEFF Research Database (Denmark)

    Ben Fekih, Ibtissem; Boukhris-Bouhachem, Sonia; Allagui, Mohamed Bechir

    2015-01-01

    Summary. The natural occurrence of fungal pathogens of aphids and their ecological host range was investigated in Tunisia from 2009 to 2012. The survey focused on aphid infesting different crops and weeds and included 10 different aphid species. Samples were collected from eight agricultural crops...... (Entomophthorales: Ancylistaceae) and Neozygites fresenii (Neozygitales: Neozygitaceae). The occurrence of entomophthoralean fungi depended on the sampling area, the bioclimatic zone, and aphid species. P. neoaphidis and E. planchoniana were the predominant pathogens infecting a wide range of aphid species whereas...... C. obscurus and N. fresenii were sporadically present on a limited number of aphid species. This study is the first survey on ecological host range of entomophthoralean fungi in Tunisia, and the first documentation of C. obscurus and N. fresenii to occur in Tunisia and Maghreb Region....

  6. Sphincterochilidae from Tunisia, with a note on the subgenus Rima Pallary, 1910 (Gastropoda, Pulmonata).

    Science.gov (United States)

    Abbes, Intidhar; Nouira, Said; Neubert, Eike

    2011-01-01

    In order to establish an updated checklist of terrestrial gastropod from Tunisia, a revision of the species of Sphincterochilidae is presented, using bibliographic and museum records and the results of our own field work. As a result, only two species, Sphincterochila candidissima and Sphincterochila tunetana, are accepted to occur in Tunisia, and their type specimens are illustrated. The study of the morphological characters of the genital organs of both species clarified their subgeneric affiliation. Comparison of Sphincterochila tunetana with Sphincterochila cariosa from Lebanonshowed that the first has to be classified within the subgenus Albea, and the latter within Sphincterochila s. str.; the subgenus Rima Pallary, 1910 remains in the synonymy of Sphincterochila s. str. Bibliographic records of Sphincterochila baetica and Sphincterochila otthiana from Tunisia could not be confirmed, the latter probably lives close to the border with Algeria.

  7. Sphincterochilidae from Tunisia, with a note on the subgenus Rima Pallary, 1910 (Gastropoda, Pulmonata

    Directory of Open Access Journals (Sweden)

    Intidhar Abbes

    2011-12-01

    Full Text Available In order to establish an updated checklist of terrestrial gastropod from Tunisia, a revision of the species of Sphincterochilidae is presented, using bibliographic and museum records and the results of our own field work. As a result, only two species, Sphincterochila candidissima and S. tunetana, are accepted to occur in Tunisia, and their type specimens are illustrated. The study of the morphological characters of the genital organs of both species clarified their subgeneric affiliation. Comparison of S. tunetana with S. cariosa from Lebanon showed that the first has to be classified within the subgenus Albea, and the latter within Sphincterochila s. str.; the subgenus Rima Pallary, 1910 remains in the synonymy of Sphincterochila s. str. Bibliographic records of S. baetica and S. otthiana from Tunisia could not be confirmed, the latter probably lives close to the border with Algeria.

  8. Inverted intracontinental basin and vertical tectonics: The Saharan Atlas in Tunisia

    Science.gov (United States)

    Rigane, Adel; Gourmelen, Claude

    2011-09-01

    The present-day architecture of the Saharan Atlas in Tunisia can be defined by two principal models: (1) The first model emphasizes a general SW-NE geological structure in the North forming successive and parallel bands (the Tellian zone, the diapir zone) and the central Atlas, which are cut by the southern Atlas ranges located within a NW-SE corridor. These zones are bordered to the East by the "North-South Axis". (2) The second model defines the Tunisian Atlas in terms of an E-W strike-slip corridor, which initially controls the sedimentary facies distribution during the Meso-Cenozoïc, and which then generates elongate en echelon folds in the sedimentary cover by dextral shearing. In this study, we aim to show that the Saharan Atlas in Tunisia appears today as a triangular megablock, that we call the Tunisian Block (TB), bounded by three structural trends (N-S, SW-NE and NW-SE) belonging to the African strike-slip fault network: (1) The eastern boundary appears as a complex faulted and folded corridor limiting the folded zone of the central Atlas in the West and the depressed zone of the Sahel in the East: it corresponds to the "North-South Axis" as defined classically in the literature. (2) The southern boundary also corresponds to a faulted belt (Gafsa-Negrine-Tozeur corridor), which cuts off the continuation of the North-South axis southward into the Gabès region; it corresponds to the Southern Saharan Atlas, delimited by the Gafsa fault in the North and the Negrine-Tozeur fault in the South. (3) The northern boundary, trending SW-NE, appears rather in the form of a reverse tectonic bundle, facing SE or S (oblique convergence), whose major feature corresponds to the El Alia-Téboursouk fault. This northern boundary cuts across and delimits the N-S corridor towards the North, in such a way that its extension is limited at both extremities. Finally, the inner part of the TB actually corresponds to a mosaic of second-order blocks, each of which contains an

  9. Kobs (Kobus kob Erxleber, 1777) activities at salt-lick spots in Kainji ...

    African Journals Online (AJOL)

    Kobs (Kobus kob Erxleber, 1777) activities at salt-lick spots in Kainji Lake National Park, Nigeria. ... Bulletin of Animal Health and Production in Africa ... Activities (foraging, ruminating, resting, salt-licking, walking, playing, agonistic, mating, vigilant and standing) of kobs (Kobus kob Erxleber, 1777) visiting two different sizes ...

  10. A cost effectiveness analysis of salt reduction policies to reduce coronary heart disease in four Eastern Mediterranean countries.

    Directory of Open Access Journals (Sweden)

    Helen Mason

    Full Text Available BACKGROUND: Coronary Heart Disease (CHD is rising in middle income countries. Population based strategies to reduce specific CHD risk factors have an important role to play in reducing overall CHD mortality. Reducing dietary salt consumption is a potentially cost-effective way to reduce CHD events. This paper presents an economic evaluation of population based salt reduction policies in Tunisia, Syria, Palestine and Turkey. METHODS AND FINDINGS: Three policies to reduce dietary salt intake were evaluated: a health promotion campaign, labelling of food packaging and mandatory reformulation of salt content in processed food. These were evaluated separately and in combination. Estimates of the effectiveness of salt reduction on blood pressure were based on a literature review. The reduction in mortality was estimated using the IMPACT CHD model specific to that country. Cumulative population health effects were quantified as life years gained (LYG over a 10 year time frame. The costs of each policy were estimated using evidence from comparable policies and expert opinion including public sector costs and costs to the food industry. Health care costs associated with CHDs were estimated using standardized unit costs. The total cost of implementing each policy was compared against the current baseline (no policy. All costs were calculated using 2010 PPP exchange rates. In all four countries most policies were cost saving compared with the baseline. The combination of all three policies (reducing salt consumption by 30% resulted in estimated cost savings of $235,000,000 and 6455 LYG in Tunisia; $39,000,000 and 31674 LYG in Syria; $6,000,000 and 2682 LYG in Palestine and $1,3000,000,000 and 378439 LYG in Turkey. CONCLUSION: Decreasing dietary salt intake will reduce coronary heart disease deaths in the four countries. A comprehensive strategy of health education and food industry actions to label and reduce salt content would save both money and lives.

  11. A Cost Effectiveness Analysis of Salt Reduction Policies to Reduce Coronary Heart Disease in Four Eastern Mediterranean Countries

    Science.gov (United States)

    Mason, Helen; Shoaibi, Azza; Ghandour, Rula; O'Flaherty, Martin; Capewell, Simon; Khatib, Rana; Jabr, Samer; Unal, Belgin; Sözmen, Kaan; Arfa, Chokri; Aissi, Wafa; Romdhane, Habiba Ben; Fouad, Fouad; Al-Ali, Radwan; Husseini, Abdullatif

    2014-01-01

    Background Coronary Heart Disease (CHD) is rising in middle income countries. Population based strategies to reduce specific CHD risk factors have an important role to play in reducing overall CHD mortality. Reducing dietary salt consumption is a potentially cost-effective way to reduce CHD events. This paper presents an economic evaluation of population based salt reduction policies in Tunisia, Syria, Palestine and Turkey. Methods and Findings Three policies to reduce dietary salt intake were evaluated: a health promotion campaign, labelling of food packaging and mandatory reformulation of salt content in processed food. These were evaluated separately and in combination. Estimates of the effectiveness of salt reduction on blood pressure were based on a literature review. The reduction in mortality was estimated using the IMPACT CHD model specific to that country. Cumulative population health effects were quantified as life years gained (LYG) over a 10 year time frame. The costs of each policy were estimated using evidence from comparable policies and expert opinion including public sector costs and costs to the food industry. Health care costs associated with CHDs were estimated using standardized unit costs. The total cost of implementing each policy was compared against the current baseline (no policy). All costs were calculated using 2010 PPP exchange rates. In all four countries most policies were cost saving compared with the baseline. The combination of all three policies (reducing salt consumption by 30%) resulted in estimated cost savings of $235,000,000 and 6455 LYG in Tunisia; $39,000,000 and 31674 LYG in Syria; $6,000,000 and 2682 LYG in Palestine and $1,3000,000,000 and 378439 LYG in Turkey. Conclusion Decreasing dietary salt intake will reduce coronary heart disease deaths in the four countries. A comprehensive strategy of health education and food industry actions to label and reduce salt content would save both money and lives. PMID:24409297

  12. A cost effectiveness analysis of salt reduction policies to reduce coronary heart disease in four Eastern Mediterranean countries.

    Science.gov (United States)

    Mason, Helen; Shoaibi, Azza; Ghandour, Rula; O'Flaherty, Martin; Capewell, Simon; Khatib, Rana; Jabr, Samer; Unal, Belgin; Sözmen, Kaan; Arfa, Chokri; Aissi, Wafa; Ben Romdhane, Habiba; Fouad, Fouad; Al-Ali, Radwan; Husseini, Abdullatif

    2014-01-01

    Coronary Heart Disease (CHD) is rising in middle income countries. Population based strategies to reduce specific CHD risk factors have an important role to play in reducing overall CHD mortality. Reducing dietary salt consumption is a potentially cost-effective way to reduce CHD events. This paper presents an economic evaluation of population based salt reduction policies in Tunisia, Syria, Palestine and Turkey. Three policies to reduce dietary salt intake were evaluated: a health promotion campaign, labelling of food packaging and mandatory reformulation of salt content in processed food. These were evaluated separately and in combination. Estimates of the effectiveness of salt reduction on blood pressure were based on a literature review. The reduction in mortality was estimated using the IMPACT CHD model specific to that country. Cumulative population health effects were quantified as life years gained (LYG) over a 10 year time frame. The costs of each policy were estimated using evidence from comparable policies and expert opinion including public sector costs and costs to the food industry. Health care costs associated with CHDs were estimated using standardized unit costs. The total cost of implementing each policy was compared against the current baseline (no policy). All costs were calculated using 2010 PPP exchange rates. In all four countries most policies were cost saving compared with the baseline. The combination of all three policies (reducing salt consumption by 30%) resulted in estimated cost savings of $235,000,000 and 6455 LYG in Tunisia; $39,000,000 and 31674 LYG in Syria; $6,000,000 and 2682 LYG in Palestine and $1,3000,000,000 and 378439 LYG in Turkey. Decreasing dietary salt intake will reduce coronary heart disease deaths in the four countries. A comprehensive strategy of health education and food industry actions to label and reduce salt content would save both money and lives.

  13. Lessons From a Comparison of Tunisia and Algeria: The Path to Democracy

    Science.gov (United States)

    2012-03-14

    and the military’s alignment played in causing a democratic transition. 45 Larbi Sadiki, "Ben Ali’s Tunisia: Democracy by Non-Democratic Means...34 British Journal of Middle Easter Studies 29.1 (May 2002): 60. 46 Larbi Sadiki, "Ben Ali’s Tunisia: Democracy by Non-Democratic Means," British Journal...revolution in authoritarian nations. After a young student from the poor interior town of Sidi -Bouzid burned himself to death in a desperate act to call

  14. Social movements and network analysis in Tunisia before the Arab Spring

    OpenAIRE

    Pérez-Altable, Laura; Blanco, Saúl; ,

    2016-01-01

    In recent years, there has been a great deal of interest on the role of social media in the so-called Arab Spring revolt, but the uprising was not the result of a sudden event. Before it began in late 2010, protests have been staged in some Arab countries that paved the way to this major event (Al-Rawi, 2014, p. 916; Cassara, 2013, p.191). As Gilad Lotan et al. noted (2011, p. 1376) each country has its own context; hence this article focusses on Tunisia. Tunisia was the first Arab country wh...

  15. Monitoring land degradation in southern Tunisia: A test of LANDSAT imagery and digital data

    Science.gov (United States)

    Hellden, U.; Stern, M.

    1980-01-01

    The possible use of LANDSAT imagery and digital data for monitoring desertification indicators in Tunisia was studied. Field data were sampled in Tunisia for estimation of mapping accuracy in maps generated through interpretation of LANDSAT false color composites and processing of LANDSAT computer compatible tapes respectively. Temporal change studies were carried out through geometric registration of computer classified windows from 1972 to classified data from 1979. Indications on land degradation were noted in some areas. No important differences, concerning results, between the interpretation approach and the computer processing approach were found.

  16. [Dermatobia hominis furuncular myiasis in a man returning from Latin America: first imported case in Tunisia].

    Science.gov (United States)

    Kaouech, E; Kallel, K; Belhadj, S; Chaker, E

    2010-04-01

    Human cutaneous myiasis is a common dermatosis in tropical zones. The purpose of this report is to describe the first imported case of furuncular myiasis caused by Dermatobia hominis (human botfly) in Tunisia. The patient was a man returning from Bolivia. Furuncular myiasis was suspected based on epidemiological data and clinical examination showing pruriginous elevated lesions. Diagnosis was confirmed by identification of Dermatobia hominis larvae. Treatment was based mainly on manual removal of larvae. Since furuncular myiasis is unknown in Tunisia, it is important to remember this parasitic disease in differential diagnosis in patients presenting boil-like inflammatory papules following travel to Latin America.

  17. The scope for inflation targeting in Tunisia: Analytical and empirical approach

    Directory of Open Access Journals (Sweden)

    Chockri Adnen

    2011-01-01

    Full Text Available The aim of our work is to identify the necessary conditions for successful transition to the regime of inflation targeting in the case of Tunisia. In this context, we analyze, first, the theoretical foundations of the policy of inflation targeting. Then, we outline the prerequisites for adopting this strategy in a country like Tunisia. Finally, based on SVAR models, we try to evaluate the transmission channels of monetary policy and identify the conditions for successful adoption of the regime of inflation targeting.

  18. L'affleurement triasique du Debadib Ben Gasseur (Nord-Ouest de la Tunisie) : diapir enraciné à épanchements latéraux dans la mer Albienne, replissé au cours des phases de compression tertiairesThe Triassic rocks of the Debadib Ben Gasseur area (northwestern Tunisia): diapir with overhangs spreading downslope in the Albian Sea and deformed during the Tertiary compressional deformations

    Science.gov (United States)

    Chikhaoui, Mongi; Jallouli, Chokri; Turki, Mohamed Moncef; Soussi, Mohamed; Braham, Ahmed; Zaghbib-Turki, Dalia

    2002-12-01

    The Triassic outcrops of the Debadib-Ben Gasseur area, located in the Kef area (northwestern Tunisia) have recently been interpreted as submarine 'salt glaciers' interbedded within the Albian deposits (J.-M. Vila et al., C. R. Acad. Sci. Paris, Ser. II 318 (1994) 1661-1667). New cartographic, drills and gravimetric data recognised evidence for an Albian diapiric stage for the Triassic rocks. The Triassic rocks as pulling out of the sedimentary cover could spread laterally as small size 'salt glaciers' before they have been deformed during the Tertiary compressional deformations. To cite this article: M. Chikhaoui et al., C. R. Geoscience 334 (2002) 1129-1133.

  19. Great Lakes

    Science.gov (United States)

    Edsall, Thomas A.; Mac, Michael J.; Opler, Paul A.; Puckett Haecker, Catherine E.; Doran, Peter D.

    1998-01-01

    The Great Lakes region, as defined here, includes the Great Lakes and their drainage basins in Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, and New York. The region also includes the portions of Minnesota, Wisconsin, and the 21 northernmost counties of Illinois that lie in the Mississippi River drainage basin, outside the floodplain of the river. The region spans about 9º of latitude and 20º of longitude and lies roughly halfway between the equator and the North Pole in a lowland corridor that extends from the Gulf of Mexico to the Arctic Ocean.The Great Lakes are the most prominent natural feature of the region (Fig. 1). They have a combined surface area of about 245,000 square kilometers and are among the largest, deepest lakes in the world. They are the largest single aggregation of fresh water on the planet (excluding the polar ice caps) and are the only glacial feature on Earth visible from the surface of the moon (The Nature Conservancy 1994a).The Great Lakes moderate the region’s climate, which presently ranges from subarctic in the north to humid continental warm in the south (Fig. 2), reflecting the movement of major weather masses from the north and south (U.S. Department of the Interior 1970; Eichenlaub 1979). The lakes act as heat sinks in summer and heat sources in winter and are major reservoirs that help humidify much of the region. They also create local precipitation belts in areas where air masses are pushed across the lakes by prevailing winds, pick up moisture from the lake surface, and then drop that moisture over land on the other side of the lake. The mean annual frost-free period—a general measure of the growing-season length for plants and some cold-blooded animals—varies from 60 days at higher elevations in the north to 160 days in lakeshore areas in the south. The climate influences the general distribution of wild plants and animals in the region and also influences the activities and distribution of the human

  20. Salt stress induced changes in germination, lipid peroxidation and ...

    African Journals Online (AJOL)

    Seeds of four lettuce (Lactuca sativa L.) genotypes viz., Great Lakes (GL), Paris Island cos, Kagraner Sommer (KS) and Isadora were assessed for their response to salt at the germination and seedling stages. The germination rate of the four varieties was comparatively studied under 0, 50, 100, 150 and 200 mM sodium ...

  1. The behaviour of salt and salt caverns

    NARCIS (Netherlands)

    Fokker, P.A.

    1995-01-01

    Salts are mined for both storage and extraction purposes, either via dry or solution mining techniques. For operational, environmental and geological purposes, it is important to understand and predict the in situ behaviour of salt, in particular the creep and strength characteristics. A

  2. Effect of Low Salt Diet on Insulin Resistance in Salt Sensitive versus Salt Resistant Hypertension

    OpenAIRE

    Garg, Rajesh; Sun, Bei; Williams, Jonathan

    2014-01-01

    Accumulating evidence shows an increase in insulin resistance on salt restriction. We compared the effect of low salt diet on insulin resistance in salt sensitive versus salt resistant hypertensive subjects. We also evaluated the relationship between salt sensitivity of blood pressure and salt sensitivity of insulin resistance in a multivariate regression model. Studies were conducted after one week of high salt (200 mmol/day Na) and one week of low salt (10 mmol/day Na) diet. Salt sensitivit...

  3. Anaplasma platys-like strains in ruminants from Tunisia.

    Science.gov (United States)

    Ben Said, Mourad; Belkahia, Hanène; El Mabrouk, Narjesse; Saidani, Mariem; Alberti, Alberto; Zobba, Rosanna; Cherif, Amal; Mahjoub, Tarek; Bouattour, Ali; Messadi, Lilia

    2017-04-01

    Molecular diagnosis of Anaplasma platys and related strains (A. platys-like) in carnivores and ruminants is challenging due to co-infections with cross-reacting strains, and require post-amplification sequencing of the hemi-nested PCR products traditionally generated by targeting the groEL gene. In this study, a Restriction Enzyme Fragment Length Polymorphism (RFLP) assay coupled to hemi-nested groEL PCR was developed to discriminate among A. platys and genetically related strains. This novel approach was used for investigating A. platys-like infection in 963 domesticated ruminants (241 goats, 355 sheep, and 367 cattle) from 22 delegations located in North Tunisia. Overall prevalence rates of A. platys-like were 22.8, 11, and 3.5% in goats, sheep, and cattle, respectively. Alignment, identity comparison, and phylogenetic analysis of the groEL sequence variants obtained in this study confirmed RFLP data suggesting that Tunisian ruminants are infected by novel unclassified Anaplasma strains genetically related to A. platys. Compared to sequencing, RFLP assay allows fast detection of A. platys and A. platys-like pathogens in the same sample and has a potential value especially when screening ticks, cats and ruminants, which can be a common host for these two bacteria. This newly developed molecular technique would provide valuable molecular tool for epidemiological studies related to A. platys as well as remove concern over specificity of serological and molecular methods routinely used to identify diverse Anaplasma strains and species in wild and domestic ruminants. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Geologic evolution and hydrocarbon prospects in the Chotts Basin, Tunisia

    Energy Technology Data Exchange (ETDEWEB)

    Johns, C. [Scott Pickford Group, Surrey (United Kingdom); Chine, A. [Entreprise Tunisienne d`Activites Petrolieres (ETAP), Tunis (Tunisia)

    1995-08-01

    The Chotts Basin, running east-west across central Tunisia, is a complex Late Paleozoic to Mesozoic graben system with a sediment thickness reaching over 5000m. It covers an area of over 15,000 km{sup 2} but is underexplored. It has been drilled by only a few wells; several of which gave oil and gas shows. A number of oil and condensate fields lie immediately south. ETAP, the national oil company, has undertaken a detailed investigation of the basin, greatly improving our understanding of its evolution and prospectivity. The basin is floored by Lower Paleozoic sediments. These occur at shallow depth on the southern flank where they were affected by periodic contemporary tectonism. The succession includes Ordovician clastics with good reservoir potential and both Ordovician and uppermost Silurian source rocks. Locally, the latter unconformably overlie Ordovician reservoir sections. The basin developed into a major, east-west trending, intracratonic wrench basin during the late Permian. Carbonate facies dominate the southern shelf area and, although lithofacies distributions are poorly constrained, the existence of quality source rocks is a strong possibility. The graben complex was inverted and partly eroded prior to deposition of Upper Triassic volcanics and sandstones. The sandstones are a proven reservoir and several leads are identified. Substantial subsidence occurred in the northern part of the basin from the Middle Jurassic to Early Cretaceous. Jurassic carbonates provide numerous reservoir sections, while Callovian shales constitute a proven, mature source rock. Large fault- and fold- related traps were formed during latest Cretaceous to Paleocene and Mio-Pliocene orogeny; they provide promising objectives.

  5. [Acute disseminated encephalomyelitis in Tunisia: Report of a pediatric cohort].

    Science.gov (United States)

    Ben Achour, N; Ben Waddey, O; Kraoua, I; Benrhouma, H; Klaa, H; Rouissi, A; Ben Youssef-Turki, I

    2015-12-01

    Acute disseminated encephalomyelitis (ADEM) is an inflammatory, demyelinating disorder of the central nervous system whose clinical features, management and outcome are incompletely understood in Tunisian population. To describe clinical, neuroimaging and laboratory features; treatment and outcome in a cohort of Tunisian children with ADEM. We conducted a retrospective review of the medical records of all children attending the Department of Child and Adolescent Neurology (Tunis) with ADEM between 2005 and 2015. Clinical, neuroimaging and laboratory features, therapeutic data and outcome were analyzed. There were 15 children (7 males and 8 females). The mean age at onset was 6.9 years. Thirteen (86.6%) patients had a prodromal event. The onset of neurological symptoms occurred within 17.6 days (4-30). Limb weakness was the most common presenting symptom (53.3%). Extrapyramidal syndrome was noticed in 6 patients (40%). Initial MRI showed a deep gray matter involvement in 7 cases (46.6%). Gadolinium enhancement at acute stage was observed in only 2 patients (13%). Cerebrospinal fluid findings did not show intrathecal oligoclonal bands. The use of high-dose IV methylprednisolone followed by oral steroid taper was associated with rapid recovery. Additional treatment with intravenous immunoglobulin was necessary in 2 patients. Complete recovery was obtained in 11 patients (73.3%). A monophasic course was noticed in 14 cases. Only one patient (5%) developed multiple sclerosis. The high frequency of prodromal events and extrapyramidal syndrome in addition to the low rate of gadolinium enhancement at acute stage seem to be the main features in our patients. Larger ADEM multicenter cohort studies in Tunisia and North Africa could provide more detailed information about this entity. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  6. Low-salt diet

    Science.gov (United States)

    Low-sodium diet; Salt restriction ... control many functions. Too much sodium in your diet can be bad for you. For most people, ... you limit salt. Try to eat a balanced diet. Buy fresh vegetables and fruits whenever possible. They ...

  7. Cryptanalysis of the LAKE Hash Family

    DEFF Research Database (Denmark)

    Biryukov, Alex; Gauravaram, Praveen; Guo, Jian

    2009-01-01

    We analyse the security of the cryptographic hash function LAKE-256 proposed at FSE 2008 by Aumasson, Meier and Phan. By exploiting non-injectivity of some of the building primitives of LAKE, we show three different collision and near-collision attacks on the compression function. The first attack...... uses differences in the chaining values and the block counter and finds collisions with complexity 233. The second attack utilizes differences in the chaining values and salt and yields collisions with complexity 242. The final attack uses differences only in the chaining values to yield near...

  8. Effects of environmental conditions on soil salinity and arid region in Tunisia

    Energy Technology Data Exchange (ETDEWEB)

    Ben Ahmed, C.; Ben Rouina, B.; Boukhris, M.

    2009-07-01

    The shortage of water resources of good water quality is becoming an issue in the arid and semi arid regions. for this reason, the use of water resources of marginal quality such as treated wastewater and saline groundwater has become and important consideration, particularly in arid region in Tunisia, where large quantities of saline water are used for irrigation. (Author)

  9. Heat Stress in Tunisia: Effects on dairy cows and potential means ...

    African Journals Online (AJOL)

    Thus, one of the challenges to dairy producers is heat stress. The objectives of this work were to characterize the environmental conditions to which Holstein cows are exposed in Tunisia using the Temperature Humidity Index (THI), examine heat stress effects on lactating cows and to suggest potential management ...

  10. Characterization of a Colletotrichum population causing anthracnose disease on Olive in northern Tunisia.

    Science.gov (United States)

    Chattaoui, M; Raya, M C; Bouri, M; Moral, J; Perez-Rodriguez, M; Trapero, A; Msallem, M; Rhouma, A

    2016-05-01

    To phenotypically, physiologically and molecularly characterize the causal agent of olive anthracnose in the northern Tunisia and to study its genetic variability and pathogenicity. A total of 43 isolates were obtained from symptomatic olives collected from four regions in northern Tunisia. A range of morphological and physiological characteristics was recorded; and a phylogenetic study, based on the sequence analysis of both internal transcribed spacers and TUB2 gene regions, was performed. Of the 43 isolates, 41 were identified as Colletotrichum acutatum s.s, and only two were affiliated to Colletotrichum gloeosporioides s.s. Two more representative Spanish isolates, included for comparison, were identified as Colletotrichum godetiae. Using six inter-simple-sequence-repeat markers, homogeneity between isolates from different locations and within the same species was recorded. In pathogenicity and virulence studies, C. gloeosporioides s.s was found to be less virulent, while the Spanish C. godetiae isolate was significantly more virulent than the Tunisian C. acutatum s.s. Olive anthracnose in the North of Tunisia is mainly caused by C. acutatum s.s species. This is the first study of olive anthracnose in Tunisia, which combines both phenotypic and molecular approaches. Colletotrichum acutatum s.s group was recorded for the first time in the country as the causal agent of olive anthracnose. © 2016 The Society for Applied Microbiology.

  11. Popular and formal Islam, and supralocal relations : the Highlands of Northwestern Tunisia, 1800-1970

    NARCIS (Netherlands)

    Binsbergen, W.M.J.

    1979-01-01

    The present paper explores the interplay between local popular Islam and the repeated introduction of formal Islam in Khrumiria, North-western Tunisia, against the background of its social and political structure and the radical changes the latter underwent in the colonial and post-colonial era. The

  12. Hepatitis E virus genotypes 1 and 3 in wastewater samples in Tunisia.

    Science.gov (United States)

    Béji-Hamza, A; Hassine-Zaafrane, M; Khélifi-Gharbi, H; Della Libera, S; Iaconelli, M; Muscillo, M; Petricca, S; Ciccaglione, A R; Bruni, R; Taffon, S; Aouni, M; La Rosa, G

    2015-01-01

    Hepatitis E represents an important public-health concern throughout the world. It is one of the leading causes of hepatitis in North Africa, Asia and the Middle East. In Tunisia, the true burden of HEV infection is still unknown. The objectives of the present study were to assess the occurrence of hepatitis E virus in Tunisia through the monitoring of urban sewage and to characterize the strains identified using molecular assays. A total of 150 sewage samples (raw and treated) were collected from three wastewater treatment plants located in the regions of Monastir and Mahdia and analyzed by nested RT-PCR using a qualitative assay targeting the methyltransferase gene in ORF1. Of these, only three samples (2 %) were found to be positive for HEV, one belonging to genotype 1 and two to genotype 3. The results of the present study indicate a low level of virus excretion among the Tunisian population. Both genotypes 1 and 3 are circulating in this country, however, possibly causing sporadic infections. The presence of the zoonotic genotype 3, known to be transmitted to humans mainly by swine and demonstrated in Tunisia for the first time in this work, raises the question of possible reservoir species, since pork products are not consumed in this country, pigs are not bred, and wild boar is not endemic. Further studies will be needed to gather information on the occurrence and diversity of HEV strains circulating among humans and animals in Tunisia, and on possible animal reservoirs.

  13. Scope, Relevance and Challenges of Financing Higher Education: The Case of Tunisia

    Science.gov (United States)

    Abdessalem, Tahar

    2011-01-01

    Like other developing countries, Tunisia has allocated increasing levels of resources to education, particularly higher education, over the past few decades, mainly through public funding. From 2005 to 2008, public expenditure on education amounted to around 7.4% of GDP, with 2% allocated to higher education. Recently, however, budgetary…

  14. Effects of Fusarium culmorum and water stress on durum wheat in Tunisia

    Science.gov (United States)

    The effects of water stress on Fusarium foot and root rot in durum wheat were investigated in growth chamber, greenhouse and field tests in Tunisia. In the seedling stage, emergence of six durum wheat cultivars in the growth chamber was significantly reduced by inoculation with Fusarium culmorum and...

  15. Diversity and distribution of Chironomidae (Insecta: Diptera of protected areas in North Tunisia

    Directory of Open Access Journals (Sweden)

    Boulaaba S.

    2014-01-01

    Full Text Available In North Africa seasonal streams called wadi are an unique habitats with serve hydrological and thermal regime. Non-biting midges take an important part of freshwater biodiversity in North Africa. We present new data on the distribution and diversity of Chironomidae in North Tunisia. Larvae, pupal exuviae and adult males of chironomids were collected from a various freshwater ecosystems from May 2005 till April 2006. The aim of this study was to recognize the pattern of midge diversity in North Tunisia to estimate ecological value of running waters in the region. In total, 79 taxa were identified. Nearly all of the taxa were typical representatives of the Palaearctic and Mediterranean complexes. The majority of the investigated sites belonged to the protected areas in North Tunisia, such as the Ichkeul National Park, the Kroumerie Mountains and the El Feija National Park, part of the Intercontinental Reserve of the Mediterranean Biosphere. Altitudinal zonation of the communities composition was found in the lowland (250 m a.s.l. with maximum of 760 m. Whereas among the data 39 species are recorded from Tunisia for the first time, the species richness of Chironomidae is higher than previously estimated.

  16. Study of genetic polymorphism of Artemisia herba-alba from Tunisia ...

    African Journals Online (AJOL)

    Artemisia herba-alba is an herbaceous aromatic and therapeutic plant widely distributed in semi-arid regions of Tunisia and is potentially usable to restore degraded ecosystems. A study of genetic variation among 216 accessions was conducted using ISSR (Inter Simple Sequence Repeat) markers to assess the ...

  17. Assessment of soil salinization risks under irrigation with brackish water in semiarid Tunisia

    NARCIS (Netherlands)

    Bouksila, F.; Bahri, A.; Berndtsson, R.; Persson, M; Rozema, J.; van der Zee, S.E.A.T.M.

    2013-01-01

    The salinity problem is becoming increasingly widespread in arid countries. In semiarid Tunisia about 50% of the irrigated land is considered as highly sensitive to salinization. To avoid the risk of salinization, it is important to control the soil salinity and keep it below plant salinity

  18. Changing Revolutions, Changing Attention? Comparing Danish Press Coverage of the Arab Spring in Tunisia and Syria

    DEFF Research Database (Denmark)

    Eskjær, Mikkel Fugl

    2012-01-01

    The Arab Spring has generated unprecedented attention to the Arab world in Western news media. This paper presents a comparative study of Danish press coverage of the uprisings in Tunisia and Syria during the early months of the Arab Spring (January-March 2011). The study is based on a mixed...

  19. Selected Bibliography of Materials; Algeria, Libya, Morocco, Tunisia. Volume 1, Number 2, 1967.

    Science.gov (United States)

    Azzouz, Azzedine; And Others

    A bibliography with abstracts of 106 items from books and articles covers materials on education in the Maghreb countries of Tunisia, Libya, Algeria, and Morocco. Special emphasis is given to the two problems besetting the area's educational system: illiteracy and multilingualism. The entries cover philosophy and theory of education,…

  20. Short Report: First Molecular Identification of Entamoeba moshkovskii in Human Stool Samples in Tunisia

    OpenAIRE

    Ben Ayed, Soumaya; Aoun, Karim; Maamouri, Nadia; Ben Abdallah, Rvm; Bouratbine, Aïda

    2008-01-01

    International audience; We report the first intestinal infections in Tunisia with Entamoeba moshkovskii in two healthy adults. Entamoeba moshkovskii cysts were distinguished from those of the morphologically identical parasites Entamoeba histolytica and Entamoeba dispar by specific nested polymerase chain reaction and sequencing.

  1. Phylogenetic Analysis and Epidemic History of Hepatitis C Virus Genotype 2 in Tunisia, North Africa.

    Directory of Open Access Journals (Sweden)

    Mouna Rajhi

    Full Text Available HCV genotype 2 (HCV-2 has a worldwide distribution with prevalence rates that vary from country to country. High genetic diversity and long-term endemicity were suggested in West African countries. A global dispersal of HCV-2 would have occurred during the 20th century, especially in European countries. In Tunisia, genotype 2 was the second prevalent genotype after genotype 1 and most isolates belong to subtypes 2c and 2k. In this study, phylogenetic analyses based on the NS5B genomic sequences of 113 Tunisian HCV isolates from subtypes 2c and 2k were carried out. A Bayesian coalescent-based framework was used to estimate the origin and the spread of these subtypes circulating in Tunisia. Phylogenetic analyses of HCV-2c sequences suggest the absence of country-specific or time-specific variants. In contrast, the phylogenetic grouping of HCV-2k sequences shows the existence of two major genetic clusters that may represent two distinct circulating variants. Coalescent analysis indicated a most recent common ancestor (tMRCA of Tunisian HCV-2c around 1886 (1869-1902 before the introduction of HCV-2k in 1901 (1867-1931. Our findings suggest that the introduction of HCV-2c in Tunisia is possibly a result of population movements between Tunisia and European population following the French colonization.

  2. Selected Bibliography of Educational Materials: Maghreb, Algeria, Libya, Morocco, Tunisia. Vol. 9, No. 3, 1975.

    Science.gov (United States)

    Azzouz, Azzedine, Comp.; And Others

    The bibliography presents 91 English language annotations of newspaper articles, journals, and government publications about education in Algeria, Libya, Morocco, and Tunisia. Although the title also includes Maghreb, this issue does not contain any annotations for that country. All articles were published during the period July-September 1975.…

  3. Selected Bibliography of Educational Materials: Algeria, Libya, Morocco, Tunisia. Vol. 4, No. 2.

    Science.gov (United States)

    Azzouz, Azzedine; And Others

    A 100-item bibliography with abstracts of books, newspaper articles, and periodical articles in English and French published predominantly in 1970 offers information on various aspects of education in Algeria, Libya, Morocco, and Tunisia. Emphasis is placed on sections dealing with educational organization in primary, secondary, vocational, and…

  4. Salt splitting using ceramic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Kurath, D.E. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-10-01

    Many radioactive aqueous wastes in the DOE complex have high concentrations of sodium that can negatively affect waste treatment and disposal operations. Sodium can decrease the durability of waste forms such as glass and is the primary contributor to large disposal volumes. Waste treatment processes such as cesium ion exchange, sludge washing, and calcination are made less efficient and more expensive because of the high sodium concentrations. Pacific Northwest National Laboratory (PNNL) and Ceramatec Inc. (Salt Lake City UT) are developing an electrochemical salt splitting process based on inorganic ceramic sodium (Na), super-ionic conductor (NaSICON) membranes that shows promise for mitigating the impact of sodium. In this process, the waste is added to the anode compartment, and an electrical potential is applied to the cell. This drives sodium ions through the membrane, but the membrane rejects most other cations (e.g., Sr{sup +2}, Cs{sup +}). The charge balance in the anode compartment is maintained by generating H{sup +} from the electrolysis of water. The charge balance in the cathode is maintained by generating OH{sup {minus}}, either from the electrolysis of water or from oxygen and water using an oxygen cathode. The normal gaseous products of the electrolysis of water are oxygen at the anode and hydrogen at the cathode. Potentially flammable gas mixtures can be prevented by providing adequate volumes of a sweep gas, using an alternative reductant or destruction of the hydrogen as it is generated. As H{sup +} is generated in the anode compartment, the pH drops. The process may be operated with either an alkaline (pH>12) or an acidic anolyte (pH <1). The benefits of salt splitting using ceramic membranes are (1) waste volume reduction and reduced chemical procurement costs by recycling of NaOH; and (2) direct reduction of sodium in process streams, which enhances subsequent operations such as cesium ion exchange, calcination, and vitrification.

  5. Bathymetry of Lake Michigan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Michigan has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  6. Bathymetry of Lake Huron

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Huron has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  7. Bathymetry of Lake Ontario

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Ontario has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  8. Great Lakes Bathymetry

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lakes Michigan, Erie, Saint Clair, Ontario and Huron has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and...

  9. Bathymetry of Lake Superior

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Superior has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  10. 21 CFR 82.51 - Lakes (FD&C).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Lakes (FD&C). 82.51 Section 82.51 Food and Drugs... PROVISIONALLY LISTED COLORS AND SPECIFICATIONS Foods, Drugs, and Cosmetics § 82.51 Lakes (FD&C). (a)(1) General... extending the aluminum salt prepared from FD&C Blue No. 1 upon the substratum would be FD&C Blue No. 1...

  11. Migration pattern of hepatitis A virus genotype IA in North-Central Tunisia.

    Science.gov (United States)

    Beji-Hamza, Abir; Taffon, Stefania; Mhalla, Salma; Lo Presti, Alessandra; Equestre, Michele; Chionne, Paola; Madonna, Elisabetta; Cella, Eleonora; Bruni, Roberto; Ciccozzi, Massimo; Aouni, Mahjoub; Ciccaglione, Anna Rita

    2015-02-08

    Hepatitis A virus (HAV) epidemiology in Tunisia has changed from high to intermediate endemicity in the last decades. However, several outbreaks continue to occur. The last reported sequences from Tunisian HAV strains date back to 2006. In order to provide an updated overview of the strains currently circulating in Tunisia, a large-scale molecular analysis of samples from hepatitis A cases was performed, the first in Tunisia. Biological samples were collected from patients with laboratory confirmed hepatitis A: 145 sera samples in Tunis, Monastir, Sousse and Kairouan from 2008 to 2013 and 45 stool samples in Mahdia in 2009. HAV isolates were characterised by nested RT-PCR (VP1/2A region) and sequencing. The sequences finally obtained from 81 samples showed 78 genotype IA and 3 genotype IB isolates. A Tunisian genotype IA sequence dataset, including both the 78 newly obtained IA sequences and 51 sequences retrieved from GenBank, was used for phylogenetic investigation, including analysis of migration pattern among six towns. Virus gene flow from Sfax and Monastir was directed to all other towns; in contrast, the gene flows from Sousse, Tunis, Mahdia and Kairouan were directed to three, two, one and no towns, respectively. Several different HAV strains co-circulate in Tunisia, but the predominant genotype still continues to be IA (78/81, 96% isolates). A complex gene flow (migration) of HAV genotype IA was observed, with Sfax and Monastir showing gene flows to all other investigated towns. This approach coupled to a wider sampling can prove useful to investigate the factors underlying the spread of HAV in Tunisia and, thus, to implement appropriate preventing measures.

  12. HPV Types and Variants Among Cervical Cancer Tumors in Three Regions of Tunisia

    Science.gov (United States)

    KrennHrubec, Keris; Mrad, Karima; Sriha, Badreddine; Ben Ayed, Farhat; Bottalico, Danielle M.; Ostolaza, Janae; Smith, Benjamin; Tchaikovska, Tatyana; Soliman, Amr S.; Burk, Robert D.

    2014-01-01

    Cervical cancer is the second most common cancer among Tunisian women, and the incidence rates vary by region. Three Tunisian registries report age-standardized rates of 6.3/105 in the central region, 5.4/105 in the north, and 2.7/105 in the south. High-risk human papillomavirus (HPV) types and their variants differ in carcinogenic potential and geographic distribution. The HPV type and variant distribution could be a factor in the differing rates between regions of Tunisia. Tumor tissue was collected from 142 Tunisian cervical cancer patients. Demographic and reproductive characteristics of the patients were abstracted from cancer registry and hospital records. HPV type and variant analyses were performed using PCR-based Luminex and dot-blot hybridization assays. Eighty-three percent of tumors were infected with at least one HPV type. European variants of HPV16/18 were the most prevalent in tumors from all three regions, with all HPV18 infections and 64% of HPV16 infections being of European lineage. A higher frequency of HPV16 was present in Northern Tunisia (80%) than in Central (68%) or Southern Tunisia (50%) (P = 0.02). HPV18/45 was significantly more common in adenocarcinomas (50%) than in squamous cell carcinomas (11%) (P = 0.004). Frequent infection with European HPV variants most likely reflects the history of European migration to Tunisia. In addition to the importance of understanding the variants of HPV in Tunisia, behavioral and cultural attitudes towards screening and age-specific infection rates should be investigated to aid the development of future vaccination and HPV screening programs and policies. PMID:21328380

  13. Evaluation of the Performance of Multiple Drought Indices for Tunisia

    Science.gov (United States)

    Geli, H. M. E.; Jedd, T.; Svoboda, M.; Wardlow, B.; Hayes, M. J.; Neale, C. M. U.; Hain, C.; Anderson, M. C.

    2016-12-01

    The recent and frequent drought events in the Middle East and Northern Africa (MENA) create an urgent need for scientists, stakeholders, and decision makers to improve the understanding of drought in order to mitigate its effects. It is well documented that drought is not caused by meteorological or hydrological conditions alone; social, economic, and political governance factors play a large part in whether the components in a water supply system are balanced. In the MENA region, for example, agricultural production can place a significant burden on water supply systems. Understanding the connection between drought and agricultural production is an important first step in developing a sound drought monitoring and mitigation system that links physical indicators with on-the-ground impacts. Drought affect crop yield, livestock health, and water resources availability, among others. A clear depiction of drought onset, duration and severity is essential to provide valuable information to adapt and mitigate drought impact. Therefore, it is important that to be able to connect and evaluate scientific drought data and informational products with societal impact data to more effectively initiate mitigation actions. This approach will further the development of drought maps that are tailored and responsive to immediate and specific societal needs for a region or country. Within the context of developing and evaluating drought impacts maps for the MENA region, this analysis investigates the use of different drought indices and indicators including the Standardized Precipitation Index (SPI), Normalized Difference Vegetation Index (NDVI) anomaly, land surface temperature (LST), and Evaporative Stress Index (ESI) for their ability to characterize historic drought events in Tunisia. Evaluation of a "drought map" product is conducted using data at the county level including crop yield, precipitation, in-country interviews with drought monitoring experts and agricultural

  14. Groundwater chemistry and radon-222 distribution in Jerba Island, Tunisia.

    Science.gov (United States)

    Telahigue, Faten; Agoubi, Belgacem; Souid, Fayza; Kharroubi, Adel

    2018-02-01

    The present study integrates hydrogeological, hydrochemical and radiogenic data of groundwater samples taken from the Plio-Quaternary unconfined aquifer of Jerba Island, southeastern Tunisia, in order to interpret the spatial variations of the groundwater quality and identify the main hydrogeochemical factors responsible for the high ion concentrations and radon-222 content in the groundwater analysed. Thirty-nine groundwater samples were collected from open wells widespread on the island. Physical parameters (EC, pH, TDS and T °) were measured, major ions (Ca 2+ , Mg 2+ , Na + , K + , Cl - , SO 4 2- , NO 3 - and HCO 3 - ) were analysed and 222 Rn concentrations were determined using a RAD7-H 2 O. Hydrogeochemical characterisation revealed that groundwater from the Jerba aquifer has several origins. Basically, two water types exist in the island. The first one, characterized by a low to moderate salinity with a chemical facies CaMgClSO 4 , characterizes the central part of Jerba (a recharge area) due to carbonate and gypsum dissolution. The second water type with high salinities, dominated by NaKCl type, was observed in coastal areas and some parts having low topographic and piezometric levels. These areas seem to be affected by the seawater intrusion process. The 222 Rn concentrations in groundwater samples in Jerba varied from 0 Bq.L -1 to 2860 Bq.L -1 with an average of 867 Bq.L -1 . The highest values were registered in the western coastal wells and near the fault of Guellala. However, the central and eastern wells showed low radon levels. Compared to 222 Rn activity in some countries with the same lithology, radon concentrations in the Jerba unconfined aquifer have higher values influenced by the structure of the aquifer and by seawater inflow enriched with 222 Rn resulting from the decay of uranium derived from phosphogypsum deposits in the gulf of Gabes. The EC and 222 Rn spatial variability in the study area were mapped using ARC Map 10.3 software

  15. [National survey of maternal mortality of 2010 : data of Tunisia].

    Science.gov (United States)

    Tej Dellagi, Rafla; Bougatef, Souha; Ben Salah, Fayçal; Ben Mansour, Nadia; Gzara, Ahlem; Gritli, Ibtissem; Ben Romdhane, H; Rachdi, M T

    2014-01-01

    Tunisia has investigated maternal mortality in 2010 to determine maternal mortality ratio (MMR) nationally and regionally, in addition to the indentifying main causes of this mortality. Describe methodology of this study and its principal findings in the region of Tunis and discuss the national maternal mortality strategy. This is a Ramos study (Reproductive Ag Mortality Studies) that consists on identifying maternal deaths from reproductive age group (RAG) women deaths. We started by the a rehearsal and targeting of (RAG) women deaths , then we investigated a next of kin person of the decedent women by verbal autopsy, thereafter we identified maternal deaths to be confidentially investigated to judge the potential avoidability of the death. The study took place in 2010, it was carried out by 5 couples of investigators supervised by a coordinator doctor. A total of 200 deaths of (RAG) women were found in Tunis, 7 deaths among them were maternal deaths, that corresponds to an MMR of 41/100000 live births. The mean age of the deceased women was 35 years. The main causes of maternal deaths were hemorrhage (3/7), thrombo-embolic diseases (2 times for7) and HELLP syndrome (1/7). Four of a total of 4 deaths (3 deaths were not marked), were avoidable. The majority of late women had a satisfying educational level, 4 of 7 had financial autonomy. All of them had pregnancy monitoring, 5 times of 7 in university hospital. All the childbirth were medically assisted, Caesarean section was carried in 6 of 7 cases. Nationally, the MMR was estimated to 44.8/100 000 LB, that to say a decrease of 35% compared to 1993. The decrease was significant for all the regions of the country, except the great Tunis where opposite trend was recorded. This could be more likely related to quality of care rather than socio-economic conditions seeing that social determinants in Tunis are favorable. In fact, the Tunisian maternal mortality strategy had essentially focused on the monitoring system of

  16. Great Lakes Science Center

    Data.gov (United States)

    Federal Laboratory Consortium — Since 1927, Great Lakes Science Center (GLSC) research has provided critical information for the sound management of Great Lakes fish populations and other important...

  17. Longevity and effectiveness of aluminum addition to reduce sediment phosphorus release and restore lake water quality

    DEFF Research Database (Denmark)

    Huser, Brian J; Egemose, Sara; Harper, Harvey

    2016-01-01

    114 lakes treated with aluminum (Al) salts to reduce internal phosphorus (P) loading were analyzed to identify factors driving longevity of post-treatment water quality improvements. Lakes varied greatly in morphology, applied Al dose, and other factors that may have affected overall treatment ef...

  18. Desulfovibrio legallis sp. nov.: a moderately halophilic, sulfate-reducing bacterium isolated from a wastewater digestor in Tunisia.

    Science.gov (United States)

    Thabet, Olfa Ben Dhia; Wafa, Terres; Eltaief, Khelifi; Cayol, Jean-Luc; Hamdi, Moktar; Fauque, Guy; Fardeau, Marie-Laure

    2011-02-01

    A new moderately halophilic sulfate-reducing bacterium (strain H₁(T) ) was enriched and isolated from a wastewater digestor in Tunisia. Cells were curved, motile rods (2-3 x 0.5 μm). Strain H₁(T) grew at temperatures between 22 and 43°C (optimum 35°C), and at pH between 5.0 and 9.2 (optimum 7.3-7.5). Strain H₁(T) required salt for growth (1-45 g of NaCl/l), with an optimum at 20-30 g/l. Sulfate, sulfite, thiosulfate, and elemental sulfur were used as terminal electron acceptors but not nitrate and nitrite. Strain H₁(T) utilized lactate, pyruvate, succinate, fumarate, ethanol, and hydrogen (in the presence of acetate and CO₂) as electron donors in the presence of sulfate as electron acceptor. The main end-products from lactate oxidation were acetate with H₂ and CO₂. The G + C content of the genomic DNA was 55%. The predominant fatty acids of strain H₁(T) were C(15:0) iso (38.8%), C(16:0) (19%), and C(14:0) iso 3OH (12.2%), and menaquinone MK-6 was the major respiratory quinone. Phylogenetic analysis of the small-subunit (SSU) ribosomal RNA (rRNA) gene sequence indicated that strain H₁(T) was affiliated to the genus Desulfovibrio. On the basis of SSU rRNA gene sequence comparisons and physiological characteristics, strain H₁(T) is proposed to be assigned to a novel species of sulfate reducers of the genus Desulfovibrio, Desulfovibrio legallis sp. nov. (= DSM 19129(T) = CCUG 54389(T)).

  19. Bacterial growth tolerance to concentrations of chlorate and perchlorate salts relevant to Mars

    Science.gov (United States)

    Al Soudi, Amer F.; Farhat, Omar; Chen, Fei; Clark, Benton C.; Schneegurt, Mark A.

    2017-07-01

    The Phoenix lander at Mars polar cap found appreciable levels of (per)chlorate salts, a mixture of perchlorate and chlorate salts of Ca, Fe, Mg and Na at levels of ~0.6% in regolith. These salts are highly hygroscopic and can form saturated brines through deliquescence, likely producing aqueous solutions with very low freezing points on Mars. To support planetary protection efforts, we have measured bacterial growth tolerance to (per)chlorate salts. Existing bacterial isolates from the Great Salt Plains of Oklahoma (NaCl-rich) and Hot Lake in Washington (MgSO4-rich) were tested in high concentrations of Mg, K and Na salts of chlorate and perchlorate. Strong growth was observed with nearly all of these salinotolerant isolates at 1% (~0.1 M) (per)chlorate salts, similar to concentrations observed in bulk soils on Mars. Growth in perchlorate salts was observed at concentrations of at least 10% (~1.0 M). Greater tolerance was observed for chlorate salts, where growth was observed to 2.75 M (>25%). Tolerance to K salts was greatest, followed by Mg salts and then Na salts. Tolerances varied among isolates, even among those within the same phylogenetic clade. Tolerant bacteria included genera that also are found in spacecraft assembly facilities. Substantial microbial tolerance to (per)chlorate salts is a concern for planetary protection since tolerant microbes contaminating spacecraft would have a greater chance for survival and proliferation, despite the harsh chemical conditions found near the surface of Mars.

  20. Submarine Salt Karst Terrains

    Directory of Open Access Journals (Sweden)

    Nico Augustin

    2016-06-01

    Full Text Available Karst terrains that develop in bodies of rock salt (taken as mainly of halite, NaCl are special not only for developing in one of the most soluble of all rocks, but also for developing in one of the weakest rocks. Salt is so weak that many surface-piercing salt diapirs extrude slow fountains of salt that that gravity spread downslope over deserts on land and over sea floors. Salt fountains in the deserts of Iran are usually so dry that they flow at only a few cm/yr but the few rain storms a decade so soak and weaken them that they surge at dm/day for a few days. We illustrate the only case where the rates at which different parts of one of the many tens of subaerial salt karst terrains in Iran flows downslope constrains the rates at which its subaerial salt karst terrains form. Normal seawater is only 10% saturated in NaCl. It should therefore be sufficiently aggressive to erode karst terrains into exposures of salt on the thousands of known submarine salt extrusions that have flowed or are still flowing over the floors of hundreds of submarine basins worldwide. However, we know of no attempt to constrain the processes that form submarine salt karst terrains on any of these of submarine salt extrusions. As on land, many potential submarine karst terrains are cloaked by clastic and pelagic sediments that are often hundreds of m thick. Nevertheless, detailed geophysical and bathymetric surveys have already mapped likely submarine salt karst terrains in at least the Gulf of Mexico, and the Red Sea. New images of these two areas are offered as clear evidence of submarine salt dissolution due to sinking or rising aggressive fluids. We suggest that repeated 3D surveys of distinctive features (± fixed seismic reflectors of such terrains could measure any downslope salt flow and thus offer an exceptional opportunity to constrain the rates at which submarine salt karst terrains develop. Such rates are of interest to all salt tectonicians and the many

  1. Analysis of Subfossil Molecular Remains of Purple Sulfur Bacteria in a Lake Sediment

    OpenAIRE

    Coolen, Marco J. L.; Overmann, Jörg

    1998-01-01

    Molecular remains of purple sulfur bacteria (Chromatiaceae) were detected in Holocene sediment layers of a meromictic salt lake (Mahoney Lake, British Columbia, Canada). The carotenoid okenone and bacteriophaeophytin a were present in sediments up to 11,000 years old. Okenone is specific for only a few species of Chromatiaceae, including Amoebobacter purpureus, which presently predominates in the chemocline bacterial community of the lake. With a primer set specific for Chromatiaceae in combi...

  2. Commodity Price Uncertainty and Manufactured Exports in Morocco and Tunisia: Some Insights from a Novel GARCH Model

    OpenAIRE

    Bouoiyour, Jamal; Selmi, Refk

    2013-01-01

    This paper attempts to assess empirically the short-run dynamic between commodity price uncertainty and manufactured exports in Morocco and Tunisia. To this end, we propose a novel model Component with Multiple Threshold-GARCH (CMT-GARCH) that extends Weighted-GARCH of Bauwens and Storti (2008). Our results clearly show a positive and significant connection between commodity price volatility and manufactured exports, which is transitory for Morocco and Tunisia (except the impact of manufactur...

  3. Stromal cell-derived factor 1 polymorphism in patients infected with HIV and implications for AIDS progression in Tunisia

    OpenAIRE

    Sameh Amara; Jorge Domenech; Faouzi Jenhani

    2010-01-01

    Sameh Amara1, Jorge Domenech2, Faouzi Jenhani31Cellular Immunology and Cytometry, National Blood Transfusion Center, Tunis, Tunisia; 2Hematopoiesis Laboratory, Faculty of Medicine, University of Tours, Tours, France; 3Faculty of Pharmacy, Unit Research in Immunology, Tunis, TunisiaBackground: An interesting finding in the epidemiology of human immunodeficiency virus (HIV) infection is that certain mutations in genes coding for chemokines, and their receptors and ligands, may confer resistance...

  4. [Problematic Internet use among teenagers in Sfax, Tunisia].

    Science.gov (United States)

    Chérif, L; Ayedi, H; Hadjkacem, I; Khemekhem, K; Khemekhem, S; Walha, A; Kossentini, I; Moalla, Y; Ghribi, F

    2015-12-01

    Use of the Internet in Tunisian society and especially among teenagers has increased in recent years. While the use of Internet is primarily intended for research and communication, the Internet has also become an important part of teenager's life. Most people use the Internet in healthy and productive ways. However, some teenagers develop a problematic use of the Internet, which is a condition also known by the term of "Internet addiction". In Tunisia, the literature does not report data on problematic Internet use prevalence among Tunisian teenagers. The aim of this study was to determine the prevalence of problematic Internet use among teenagers, in the urban area of Sfax. This transversal study was carried out between the 15th January and the 15th February 2009. Participants were 600, first to third grade secondary school students, aged 14 to 20. They were recruited from seven secondary schools randomly selected in the urban area in Sfax City. The self-administered Young's 8-item questionnaire was used in this survey. Participants who scored five or more can be considered problematic Internet users. Finally, 587 valid data samples were collected, 263 (44%) males and 324 (56%) females. Eighty-five percent of the participants were in the 15-17 age range. The mean age was 16 years (±1.26). The prevalence of problematic Internet use was 18.05% (total of 587 students). The sex-ratio was 0.75. The problematic Internet use was not correlated with sex. The average time of Internet use per day among problematic Internet users was 4.5hours (±2.84) against 1.02hours (±1.56) among non problematic Internet users (P=0.000). In this study, the prevalence of problematic Internet use was higher than that reported in previous studies. Two facts can explain this: first, the use of the only self-administered questionnaire does not distinguish between a simple abuse and a problematic Internet use. A psychiatric examination is essential to support the diagnosis of problematic

  5. Analysis of elements in lake sediment samples by PIXE spectrometry

    Science.gov (United States)

    Chelarescu, E. D.; Radulescu, C.; Stihi, C.; Bretcan, P.; Tanislav, D.; Dulama, I. D.; Stirbescu, R. M.; Teodorescu, S.; Bucurica, I. A.; Andrei, R.; Morarescu, C.

    2017-09-01

    This work aims to determine the concentrations of several elements (e.g. Pb, Ni, Zn, Mn, Cr, and Fe) from lake sediments, in order to characterize their origin and evolution. Particle Induced X-ray Emission (PIXE) technique using the 3 MV Tandetron™ particle accelerator from National Institute for R&D in Physics and Nuclear Engineering ;Horia Hulubei; (IFIN-HH), Magurele-Bucharest, Romania, was applied. Sediment cores from different salt lakes from Romania (i.e. Amara Lake, Caineni Lake, and Movila Miresii Lake) were collected, in August 2015. The content of Pb, Cr, Mn, Fe, and Ni from sediment samples show similarities with other data presented in literature and international regulation. The Zn was the only element with a higher content in all samples (e.g. maximum 401.7-517.3 mg/kg d.w.).

  6. A multi-temporal analysis for change assessment and estimation of algal bloom in Sambhar Lake, Rajasthan, India.

    Science.gov (United States)

    Vijay, Ritesh; Pinto, Shannon M; Kushwaha, Vikash K; Pal, Sukdeb; Nandy, Tapas

    2016-09-01

    Sambhar Lake in Rajasthan, India is the major inland salt water lake producing salt for centuries. The present study addresses the monitoring changes in and around the lake and its consequent effect on the lake water ecology. For this, satellite images of the years 1976, 1981, 1997, and 2013 are analyzed for land use land cover classes. Significant reduction in the water body is observed in contrast with the increase in salt pan around the periphery of lake and wetland classes. Further, the extent of water body and algae in the lake are delineated as per normalized difference water index and normalized difference vegetation index. Rainfall data do not indicate any major change in the pattern, but drastic decrease in the extent of water body and significant increase in algal bloom are serious concerns for the lake's existence. This may be due to surrounding anthropogenic activities and construction of check dams and anicuts in the lake catchment which curtail the runoff into the lake and provide favorable growth of algae. Sambhar Lake, being declared as a wetland according to the Ramsar Convention, is necessary to protect and conserve the ecological importance of the lake through sustainable planning and management.

  7. [Ecosystem services valuation of Qinghai Lake].

    Science.gov (United States)

    Jiang, Bo; Zhang, Lu; Ouyang, Zhi-yun

    2015-10-01

    Qinghai Lake is the largest inland and salt water lake in China, and provides important ecosystem services to beneficiaries. Economic valuation of wetland ecosystem services from Qinghai Lake can reveal the direct contribution of lake ecosystems to beneficiaries using economic data, which can advance the incorporation of wetland protection of Qinghai Lake into economic tradeoffs and decision analyses. In this paper, we established a final ecosystem services valuation system based on the underlying ecological mechanisms and regional socio-economic conditions. We then evaluated the eco-economic value provided by the wetlands at Qinghai Lake to beneficiaries in 2012 using the market value method, replacement cost method, zonal travel cost method, and contingent valuation method. According to the valuation result, the total economic values of the final ecosystem services provided by the wetlands at Qinghai Lake were estimated to be 6749.08 x 10(8) yuan RMB in 2012, among which the value of water storage service and climate regulation service were 4797.57 x 10(8) and 1929.34 x 10(8) yuan RMB, accounting for 71.1% and 28.6% of the total value, respectively. The economic value of the 8 final ecosystem services was ranked from greatest to lowest as: water storage service > climate regulation service > recreation and tourism service > non-use value > oxygen release service > raw material production service > carbon sequestration service > food production service. The evaluation result of this paper reflects the substantial value that the wetlands of Qinghai Lake provide to beneficiaries using monetary values, which has the potential to help increase wetland protection awareness among the public and decision-makers, and inform managers about ways to create ecological compensation incentives. The final ecosystem service evaluation system presented in this paper will offer guidance on separating intermediate services and final services, and establishing monitoring programs for

  8. Trace Elements concentration and distribution across the Lake Chad Basin

    Science.gov (United States)

    Ndunguru, G. G.; Goni, I. B.; Mulugeta, V.; Grindley, J.; Banks, M. L.; Lee, J.; Adegoke, J. O.

    2009-12-01

    The Lake Chad, which is the largest Lake in West Africa, is situated between the latitude 12 ½ and 14 ½ north and longitude 130 east of the Southern fringe of the Sahara Desert. About 25 % of the Lake Chad lies within Nigeria, while the Republic of Cameroon, Chad and Niger share the rest of it. Lake Chad is completely landlocked and has no outlets; therefore loss of water is mainly through high rates of evaporation unlike similar Lakes in other parts of the World. The Lake Chad waters are fresh and of good quality with very low salt content which makes it suitable for irrigated agriculture. This study was carried out from upper stream to lower stream leading from Kano to the Damaturu region which is one of several water bodies that supply Lake Chad. Soil samples were collected from over seventy five sites and analyzed for ten Trace Elements(Be, Cd, Co, Cu, Mn,Fe, Mo, Pb, Zn, and Cr) using the Inductively Coupled Plasma (ICP)-OES. Assessment and Monitoring of Trace Elements concentrations are vital because they impact environment and can affect the human healthy. Since little is known about the Trace Elements status in Lake Chad Basin. The result in this study provides baseline information on the distribution and concentration of Trace Elements along the Lake Chad Basin.

  9. Hydroxycarboxylic acids and salts

    Energy Technology Data Exchange (ETDEWEB)

    Kiely, Donald E; Hash, Kirk R; Kramer-Presta, Kylie; Smith, Tyler N

    2015-02-24

    Compositions which inhibit corrosion and alter the physical properties of concrete (admixtures) are prepared from salt mixtures of hydroxycarboxylic acids, carboxylic acids, and nitric acid. The salt mixtures are prepared by neutralizing acid product mixtures from the oxidation of polyols using nitric acid and oxygen as the oxidizing agents. Nitric acid is removed from the hydroxycarboxylic acids by evaporation and diffusion dialysis.

  10. SALT for Language Acquisition.

    Science.gov (United States)

    Bancroft, W. Jane

    1996-01-01

    Discusses Schuster's Suggestive-Accelerative Learning Techniques (SALT) Method, which combines Lozanov's Suggestopedia with such American methods as Asher's Total Physical Response and Galyean's Confluent Education. The article argues that students trained with the SALT Method have higher achievement scores and better attitudes than others. (14…

  11. Epidemiological studies on Fasciola hepatica in Gafsa oases (South West of Tunisia

    Directory of Open Access Journals (Sweden)

    Hammami H.

    2007-09-01

    Full Text Available Epidemiological investigations on Fasciola hepatica fasciolasis were carried out from July 2004 to June 2005 in the Gafsa oases (Tunisia after the detection of a human case. Three habitats were studied: one in El Gsar and two in Ain Soltan. The prevalence of human infection was 6.6 %. The presence of the parasite was detected through serology in 14.3 % of cattle, 35 % of sheep and 68.4 % of goats. The plants Apium nodiflorum, Oxalis cernua and Sonchus maritimus were suspected to be at the origin of animal contamination and Apium nodiflorum was incriminated in human infection. The prevalence of the infection of the intermediate host Galba truncatula (G. truncatula was 19.2 % from July 2004 to June 2005. Gafsa oases constitute a new location for the development of fasciolasis in the southern west of Tunisia.

  12. FOOD SECURITY IN TUNISIA WITHIN WATER SCARCITY THE RELATIVE IMPORTANCE OF THE MEAT SECTOR

    Directory of Open Access Journals (Sweden)

    Emna Ouertani

    2016-01-01

    Full Text Available This paper analyzes the evolution of food and nutrition security in Tunisia, judges its sustainability within water scarcity conditions and free trade areas, with a specific focus on the meat sector. For such purpose, the FAO indicators and Food Balance Sheets, as well as the Global Food Security Index are all analyzed. Virtual water, owed to meat and cereals for animal feed production and trade, was estimated to expect food security sustainability. Results indicated that Tunisian food and nutrition security (FNS has been improved over the years, but its stability remains vulnerable because of the political and economic risks and the dependence of Tunisia on imported cereals for animal feed due to water scarcity. Tunisian agricultural policy, especially in both sectors of cereals and meat, should be readjusted to guarantee food and nutrition sustainability.

  13. VALORIZATION ABOVEGROUND OF THE EXTRACT OF COMPOST OVINE FOR FERTIGATION OF THE VEGETABLES PLANTS IN TUNISIA

    Directory of Open Access Journals (Sweden)

    Y. M’Sadak

    2013-12-01

    Full Text Available The main objective of this study was to highlight the fertilizing capacity of the extract of ovine compost (prepared to the simple infusion in gardening nursery, while specifying the appropriate ratios of extraction and dilution ,for soilless plant fertigation intended for two strategic summer crops in Tunisia: seasonal tomato and seasonal pepper. It is clear that such extraction ratio of 1: 5 is effective for plants fertigation of two considered species. In addition, it has been shown that 200 times dilution of the concentrated extract is beneficial for the growth of tomato plants. However, this organic liquid fertilizer with different dilutions applied and in the experimental conditions adopted, wasn’t moderately efficient in stimulating the growth of pepper plants. The importance of this type of compost produced from sheep biomass, widely available in Tunisia, encourage the diversification of its exploitation, which is the object of this preliminary work, deserving more future investigations.

  14. Infestation of the spur-thighed tortoise (Testudo graeca) by Hyalomma aegyptium in Tunisia.

    Science.gov (United States)

    Gharbi, Mohamed; Rjeibi, Mohamed Ridha; Rouatbi, Mariem; Mabrouk, Moez; Mhadhbi, Moez; Amairia, Safa; Amdouni, Yosra; Boussaadoun, Mohamed Anis

    2015-04-01

    We examined 210 spur-thighed tortoises (Testudo graeca) for the presence of ticks in Tunisia during May 2014. A total number of 602 adult ticks were collected and identified leading to the estimation of parasitological indicators. All the ticks belonged to a single species: Hyalomma aegyptium. The mean infestation prevalence was 66.2%, mean overall infestation intensity and abundance were 4.33 and 2.86 ticks/tortoise respectively. Our survey showed that tortoises were significantly more infested by male ticks than females (pTunisia; further investigations are needed to determine exactly the role of this tick species in the transmission of different zoonotic pathogens. Copyright © 2015 Elsevier GmbH. All rights reserved.

  15. International financial institutions and health in Egypt and Tunisia: change or continuity?

    Science.gov (United States)

    Ismail, Sharif

    2013-01-01

    The revolutions in Egypt and Tunisia appeared to herald a re-casting of International Monetary Fund and World Bank policy across the region. Public pronouncements by the heads of both institutions in the months following February 2011 acknowledged flaws in their approach to macroeconomic advice, against a background of worsening socioeconomic indicators, widespread youth unemployment, and widening health inequalities. Evidence on the ground, however, suggests continuity rather than change in international financial institution policies in Egypt and Tunisia, notwithstanding the emergence of a powerful new player-the European Bank for Reconstruction and Development. In the long term, new electoral realities and hardening public opposition in both countries seem likely to force a fundamentally different relationship between regional governments and the major international financial institutions than existed before 2011.

  16. Limnology of Eifel maar lakes

    National Research Council Canada - National Science Library

    Scharf, Burkhard W; Björk, Sven

    1992-01-01

    ... & morphometry - Physical & chemical characteristics - Calcite precipitation & solution in Lake Laacher See - Investigations using sediment traps in Lake Gemundener Maar - Phytoplankton of Lake Weinfelder Maar...

  17. Lake salinity variations resulting from wind direction, Gobi Desert, China

    Science.gov (United States)

    Bradley, D. C.; Cartwright, I.; Currell, M.

    2010-12-01

    The southern reaches of the Gobi desert, central China, host a large number (~50) of shallow (water table. The resultant lakes are of particular interest, not only because they are host to a number of unique ecosystems, including several rare species, but also because they are very susceptible to environmental disturbances. Physical development of the lakes is a clear threat, but also small scale withdrawal of groundwater in proximity to the lakes can cause a drop in the water table, forcing it below the lake floor, and consequently causing many lakes to dry up. Due to their inaccessibility, many of these lakes have remained relatively untouched by development, and only those lakes closest to the eastern edge of the desert have been utilized directly for either salt harvesting or tourism. This paper reports on research from both pristine and developed lakes, and reveals a higher TDS (20-50mS/cm compared to 0.5-5mS/cm) in the northern end relative to the southern end for undisturbed lakes. Water entering the southern end of the lakes is chemically identical to the local groundwater (TDS ~0.5mS/cm). This geographic difference in lake properties is remarkable, not only in terms of chemical variation, but also in terms of plant variety and abundance. Stable isotopes show a clear evaporation trend for these lakes, increasing from the southern tip, to the northern tip of individual lakes (-3 to -1‰ in the south, compared with 2-8‰ in the north, and -6 to -3‰ in the groundwater for δ2H). TDS likewise increases with increasing isotopic fractionation. The primary wind direction fluctuates from the southeast to the east, causing the movement of water from the southern end of the lake to the northern, and aiding in the evaporation. Once at the northern end of the lake, the water’s increased density causes it to sink back into the groundwater. In this way, the prevailing wind effectively keeps the fresh and saline waters separate, even though they are part of the same

  18. Tectonic evolution of the northern African margin in Tunisia from paleostress data and sedimentary record

    Science.gov (United States)

    Bouaziz, Samir; Barrier, Eric; Soussi, Mohamed; Turki, Mohamed M.; Zouari, Hédi

    2002-11-01

    A reconstruction of the tectonic evolution of the northern African margin in Tunisia since the Late Permian combining paleostress, tectonic stratigraphic and sedimentary approaches allows the characterization of several major periods corresponding to consistent stress patterns. The extension lasting from the Late Permian to the Middle Triassic is contemporaneous of the rifting related to the break up of Pangea. During Liassic times, regional extensional tectonics originated the dislocation of the initial continental platform. In northern Tunisia, the evolution of the Liassic NE-SW rifting led during Dogger times to the North African passive continental margin, whereas in southern Tunisia, a N-S extension, associated with E-W trending subsiding basins, lasted from the Jurassic until the Early Cretaceous. After an Upper Aptian-Early Albian transpressional event, NE-SW to ENE-WSW trending extensions prevailed during Late Cretaceous in relationship with the general tectonic evolution of the northeastern African plate. The inversions started in the Late Maastrichtian-Paleocene in northern Tunisia, probably as a consequence of the Africa-Eurasia convergence. Two major NW-SE trending compressions occurred in the Late Eocene and in the Middle-Late Miocene alternating with extensional periods in the Eocene, Oligocene, Early-Middle Miocene and Pliocene. The latter compressional event led to the complete inversion of the basins of the northwestern African plate, originating the Maghrebide chain. Such a study, supported by a high density of paleostress data and including complementary structural and stratigraphic approaches, provides a reliable way of determining the regional tectonic evolution.

  19. HYRESS project. Study case of Tunisia. Installation, set-up and first results

    Energy Technology Data Exchange (ETDEWEB)

    Cendagorta, M.; Friend, M.; Lopez-Manzanares, L.; Rodriguez, J. [Poligono Industrial de Granadilla, Tenerife (Spain). Inst. Tecnologico y de Energias Renovables, S.A.; El Khazen, A. [Agence Nationale pour la Maitrise de l' Energie, Tunis (Tunisia); Linares, A.

    2010-07-01

    In the framework of the HYRESS project, a minigrid has been designed and installed at the village of Ksar Ghilene, in southern Tunisia. This project, developed from the perspective of knowledge transfer, will allow the installation of an underground minigrid during the trimester of 2010. STEG, Tunisian national electricity supplier, will finish civil works by May 2010. It is expected to have first results of system behaviour by the end of May or April 2010. (orig.)

  20. ?This Is Real Misery?: Experiences of Women Denied Legal Abortion in Tunisia

    OpenAIRE

    Selma Hajri; Sarah Raifman; Caitlin Gerdts; Sarah Baum; Diana Greene Foster

    2015-01-01

    Barriers to accessing legal abortion services in Tunisia are increasing, despite a liberal abortion law, and women are often denied wanted legal abortion services. In this paper, we seek to explore the reasons for abortion denial and whether these reasons had a legal or medical basis. We also identify barriers women faced in accessing abortion and make recommendations for improved access to quality abortion care. We recruited women immediately after they had been turned away from legal aborti...

  1. Spatial variability of soil aggregate stability at the scale of an agricultural region in Tunisia

    OpenAIRE

    Annabi, M.; Raclot, Damien; Bahri, H.; Bailly, J. S.; Gomez, Cécile; Le Bissonnais, Y.

    2017-01-01

    International audience; Soil aggregate stability is a key factor in soil resistance to water erosion, which is a threat to soils in a large part of northern Tunisia. The analysis of the spatial variability of soil aggregate stability provides both agronomic and environmentally useful information. However, extensive measurements of soil aggregate stability remain tedious and expensive. This study explores two different approaches as alternative to measurements of soil aggregate stability. One ...

  2. One hundred years after Pinctada: an update on alien Mollusca in Tunisia

    Directory of Open Access Journals (Sweden)

    M. ANTIT

    2011-04-01

    The occurrence of aliens in Tunisia is balanced between presumably Lessepsian species of tropical Indo-Pacific origin, and species from other sources including species from the Tropical Atlantic introduced through shipping. Nevertheless there is a prevalence of Lessepsian species towards the Gulf of Gabes in the south, whereas the shipping activity in Tunis harbour may be the main pathway of introduction in the north.

  3. Sero-epidemiological survey of Crimean-Congo hemorrhagic fever virus in Tunisia

    OpenAIRE

    Wasfi Fares; Dowall Stuart; Ghabbari Tayssir; Bosworth Andrew; Chakroun Mohamed; Varghese Anitha; Tiouiri Hanene; Ben Jemaa Mounir; Znazen Abir; Hewson Roger; Zhioua Elyes; Letaief Amel

    2016-01-01

    Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease associated with a high case fatality rate and transmitted mainly by Hyalomma marginatum. The geographical distribution of H. marginatum covers most of the Western Mediterranean basin. We aimed to investigate whether CCHF virus (CCHFv) is circulating in Tunisia. Samples from unexplained acute febrile patients (n?=?181) and a high risk group of humans, mainly slaughter workers (n?=?38), were collected in the summer of 2014 and analy...

  4. Expanding the Technology Acceptance Model to Examine Internet Banking Adoption in Tunisia Country

    OpenAIRE

    Wadie Nasri; Charfeddine Lanouar; Anis Allagui

    2013-01-01

    This paper aims to empirically examine the factors that affect the adoption of Internet banking in Tunisia. In order to explain the factors, this paper extends the “Technology Acceptance Model†by adding additional external factors such as security and privacy, self efficacy, social influence, and awareness of services and its benefits. The findings of the study suggests that the security and privacy, self efficacy, social influence, and awareness of services and its benefits have signific...

  5. FOOD SECURITY IN TUNISIA WITHIN WATER SCARCITY THE RELATIVE IMPORTANCE OF THE MEAT SECTOR

    OpenAIRE

    Emna Ouertani

    2016-01-01

    This paper analyzes the evolution of food and nutrition security in Tunisia, judges its sustainability within water scarcity conditions and free trade areas, with a specific focus on the meat sector. For such purpose, the FAO indicators and Food Balance Sheets, as well as the Global Food Security Index are all analyzed. Virtual water, owed to meat and cereals for animal feed production and trade, was estimated to expect food security sustainability. Results indicated that Tunis...

  6. Prevalence of COPD and Tobacco Smoking in Tunisia — Results from the BOLD Study

    OpenAIRE

    Daldoul, Hager; Denguezli, Meriam; Jithoo, Anamika; Gnatiuc, Louisa; Buist, Sonia; Burney, Peter; Tabka, Zouhair; Harrabi, Imed

    2013-01-01

    In Tunisia, there is a paucity of population-based data on Chronic Obstructive Pulmonary Disease (COPD) prevalence. To address this problem, we estimated the prevalence of COPD following the Burden of Lung Disease Initiative. We surveyed 807 adults aged 40+ years and have collected information on respiratory history and symptoms, risk factors for COPD and quality of life. Post-bronchodilator spirometry was performed and COPD and its stages were defined according to the Global Initiative for ...

  7. Middle-Upper Triassic and Middle Jurassic tetrapod track assemblages of southern Tunisia, Sahara Platform

    Science.gov (United States)

    Niedźwiedzki, Grzegorz; Soussi, Mohamed; Boukhalfa, Kamel; Gierliński, Gerard D.

    2017-05-01

    Three tetrapod track assemblages from the early-middle Mesozoic of southern Tunisia are reported. The strata exposed at the Tejra 2 clay-pit near the Medenine and Rehach site, located in the vicinity of Kirchaou, contain the first tetrapod tracks found in the Triassic of Tunisia. The Middle Jurassic (early Aalenian) dinosaur tracks are reported from the Mestaoua plain near Tataouine. In the Middle Triassic outcrop of the Tejra 2 clay-pit, tridactyl tracks of small and medium-sized dinosauromorphs, were discovered. These tracks represent the oldest evidence of dinosaur-lineage elements in the Triassic deposits of Tunisia. Similar tracks have been described from the Middle Triassic of Argentina, France and Morocco. An isolated set of the manus and pes of a quadrupedal tetrapod discovered in Late Triassic Rehach tracksite is referred to a therapsid tracemaker. The Middle Jurassic deposits of the Mestaoua plain reveal small and large tridactyl theropod dinosaur tracks (Theropoda track indet. A-C). Based on comparison with the abundant record of Triassic tetrapod ichnofossils from Europe and North America, the ichnofauna described here indicates the presence of a therapsid-dinosauromorph ichnoassociation (without typical Chirotheriidae tracks) in the Middle and Late Triassic, which sheds light on the dispersal of the Middle-Upper Triassic tetrapod ichnofaunas in this part of Gondwana. The reported Middle Jurassic ichnofauna show close similarities to dinosaur track assemblages from the Lower and Middle Jurassic of northwestern Africa, North America, Europe and also southeastern Asia. Sedimentological and lithostratigraphic data of each new tracksite have been defined on published data and new observations. Taken together, these discoveries present a tantalizing window into the evolutionary history of tetrapods from the Triassic and Jurassic of southern Tunisia. Given the limited early Mesozoic tetrapod record from the region, these discoveries are of both temporal and

  8. Features of Constitutional Development in Tunisia and Egypt after the «Arab Spring»

    Directory of Open Access Journals (Sweden)

    M A Sapronova

    2014-12-01

    Full Text Available The article analyses regulation of new constitutions of Tunisia and Egypt adopted after shocks of the «Arab spring», which restore constitutional state institutions of these countries. Special attention is devoted to new constitutional regulation, which change the character of the state system and the political regime as well as to problem to secure Islam and Shariat at basic laws of these countries.

  9. Climate change impacts on agriculture: A panel cointegration approach and application to Tunisia

    OpenAIRE

    BEN ZAIED, YOUNES; Zouabi, Oussama

    2015-01-01

    This paper proposes to model the long run impact of climate change on olive output in Tunisia, the third largest olive-oil producing country in the world, using panel cointegration techniques. The long run analysis reveals that temperature increase and inappropriate working tools reduce olive output in semi arid areas. Therefore, we propose an appropriate training for workers to develop their skills and public policy subsidizing the innovation of used capital stock at least in the south. We ...

  10. Excessive carbohydrate intake in pregnancy and neonatal obesity: study in Cap Bon, Tunisia.

    OpenAIRE

    de Schampheleire, I; Parent, M A; Chatteur, C

    1980-01-01

    A high incidence (over 20%) of obesity was found in 250 neonates living in a rural area of Tunisia, by using weight and ponderal index per gestational age as the nutritional index. Maternal diabetes was probably excluded. Two surveys on nutritional habits--one on the general population and the other on pregnant women--showed a tendency to consume a high carbohydrate and low protein diet. The effect of a badly balanced maternal diet on the fetus is discussed.

  11. An epidemiological and genetic study of congenital profound deafness in Tunisia (governorate of Nabeul).

    OpenAIRE

    Ben Arab, S; Bonaïti-Pellié, C.; Belkahia, A

    1990-01-01

    An epidemiological and genetic study of profound deafness has been undertaken in the governorate of Nabeul in Tunisia. This paper deals with sensorineural deafness with no associated abnormalities. The prevalence was estimated to be 0.0007 and four clusters could be identified, two of which represent 51% and 34% respectively of the total number of cases. Segregation analysis performed in 29 pedigrees containing 415 subjects with 129 affected cases provided evidence for simple recessive inheri...

  12. Vegetative habitat selection of Scimitar horned oryx (Oryx dammah in Bouhedma National Park, Southern Tunisia

    Directory of Open Access Journals (Sweden)

    Houssem chedli Traouit Beyouli

    2016-07-01

    Full Text Available The present study aims to analyze the habitat selection of the Scimitar horned oryx, reintroduced in Bouhedma National Park (south Tunisia and to identify the phytoecological factors affecting their occurrence during winter 2011 and spring 2012. Multivariate analyses of variance (MANOVA performed by SAS package revealed that the vegetation is not the main factor in the selection of habitat by oryx in the park. It avoids glaze and mountain areas despite the presence of palatable species.

  13. Resedimented salt deposits

    Energy Technology Data Exchange (ETDEWEB)

    Slaczka, A.; Kolasa, K. (Jagiellonian Univ., Krakow (Poland))

    1988-08-01

    Carparthian foredeep's Wieliczka salt mine, unique gravity deposits were lately distinguished. They are mainly built of salt particles and blocks with a small admixture of fragments of Miocene marls and Carpathian rocks, deposited on precipitated salt. The pattern of sediment distribution is similar to a submarine fan. Gravels are dominant in the upper part and sands in lower levels, creating a series of lobes. Coarse-grained deposits are represented by disorganized, self-supported conglomerates passing into matrix-supported ones, locally with gradation, and pebbly sandstones consisting of salt grains and scattered boulder-size clasts. The latter may show in the upper part of a single bed as indistinct cross-bedding and parallel lamination. These sediments are interpreted as debris-flow and high-density turbidity current deposits. Salt sandstones (saltstones) which build a lower part of the fan often show Bouma sequences and are interpreted as turbidity-current deposits. The fan deposits are covered by a thick series of debrites (olistostromes) which consist of clay matrix with salt grains and boulders. The latter as represented by huge (up to 100,000 m{sup 3}) salt blocks, fragments of Miocene marls and Carpathian rocks. These salt debrites represent slumps and debris-flow deposits. The material for resedimented deposits was derived from the southern part of the salt basin and from the adjacent, advancing Carpathian orogen. The authors believe the distinct coarsening-upward sequence of the series is the result of progressive intensification of tectonic movements with paroxysm during the sedimentation of salt debrites (about 15 Ma).

  14. Mutational founder effect in recessive dystrophic epidermolysis bullosa families from Southern Tunisia.

    Science.gov (United States)

    Ben Brick, Ahlem Sabrine; Laroussi, Nadia; Mesrati, Hela; Kefi, Rym; Bchetnia, Mbarka; Lasram, Khaled; Ben Halim, Nizar; Romdhane, Lilia; Ouragini, Houyem; Marrakchi, Salaheddine; Boubaker, Mohamed Samir; Meddeb Cherif, Mounira; Castiglia, Daniele; Hovnanian, Alain; Abdelhak, Sonia; Turki, Hamida

    2014-05-01

    Dystrophic epidermolysis bullosa (DEB) is a group of heritable bullous skin disorders caused by mutations in the COL7A1 gene. One of the most severe forms of DEB is the severe generalized [recessive dystrophic epidermolysis bullosa (RDEB-SG)] subtype, which is inherited in an autosomal recessive manner. This subtype is most often due to COL7A1 mutations resulting in a premature termination codon on both alleles. We report here, the molecular investigation of 15 patients belonging to 14 nuclear families from the city of Sfax in Southern Tunisia, with clinical features of RDEB-SG complicated by squamous cell carcinoma in 3 patients. We identified two novel mutations, p.Val769LeufsX1 and p.Ala2297SerfsX91, in addition to one previously reported mutation (p.Arg2063Trp). The p.Val769LeufsX1 mutation was shared by 11 families and haplotype analysis indicated that it is a founder mutation. The p.Ala2297SerfsX91 mutation was a private mutation found in only one family. Together with the previously described recurrent mutations in Tunisia, screening for the founder p.Val769LeufsX1 mutation should provide a rapid molecular diagnosis tool for mutation screening in RDEB patients from Southern Tunisia and possibly from other Mediterranean populations sharing the same genetic background.

  15. Prevalence and Predictors of Internet Addiction among College Students in Sousse, Tunisia.

    Science.gov (United States)

    Mellouli, Menel; Zammit, Nawel; Limam, Manel; Elghardallou, Meriam; Mtiraoui, Ali; Ajmi, Thouraya; Zedini, Chekib

    2018-01-02

    Internet represents a revolution in the world of technology and communication all over the world including Tunisia. However, this technology has also introduced problematic use, especially among students. The current study aimed to determine the prevalence of Internet addiction among college students and its predictors in the region of Sousse, Tunisia. A cross-sectional study. The current study was conducted in the colleges of Sousse, Tunisia in 2012-2013. A self-administrated questionnaire was used to collect data from 556 students in 5 randomly selected colleges from the region. Collected data concerned socio-demographic characteristics, substances use and internet addiction using the Young Internet Addiction Test. The response rate was 96%. The mean age of participants was 21.8±2.2 yr. Females represented 51.8% of them. Poor control of internet use was found among 280 (54.0%; CI95%: 49.7, 58.3%) participants. Low education levels among parents, the young age, lifetime tobacco use and lifetime illicit drugs use were significantly associated with poor control of internet use among students (Paddiction.

  16. Sero-epidemiological survey of Crimean-Congo hemorrhagic fever virus in Tunisia.

    Science.gov (United States)

    Wasfi, Fares; Dowall, Stuart; Ghabbari, Tayssir; Bosworth, Andrew; Chakroun, Mohamed; Varghese, Anitha; Tiouiri, Hanene; Ben Jemaa, Mounir; Znazen, Abir; Hewson, Roger; Zhioua, Elyes; Letaief, Amel

    2016-01-01

    Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease associated with a high case fatality rate and transmitted mainly by Hyalomma marginatum. The geographical distribution of H. marginatum covers most of the Western Mediterranean basin. We aimed to investigate whether CCHF virus (CCHFv) is circulating in Tunisia. Samples from unexplained acute febrile patients (n = 181) and a high risk group of humans, mainly slaughter workers (n = 38), were collected in the summer of 2014 and analyzed for exposure to CCHFv using serological tests and real-time RT-PCR. Ticks were collected from Northern and Southern Tunisia during May-June 2014 and examined for the presence of CCHFv by real-time RT-PCR. Of the 181 febrile patients, 5 showed only high titers of IgM suggesting a recent exposure to CCHFv. Among 38 slaughter workers, 2 had IgG anti-CCHFv responses yielding a seroprevalence of 5.2%. No CCHFv was detected in ticks and sera. Our results provide evidence of human exposure to CCHFv in Tunisia. © F. Wasfi et al., published by EDP Sciences, 2016.

  17. Sero-epidemiological survey of Crimean-Congo hemorrhagic fever virus in Tunisia

    Directory of Open Access Journals (Sweden)

    Wasfi Fares

    2016-01-01

    Full Text Available Crimean-Congo hemorrhagic fever (CCHF is a tick-borne disease associated with a high case fatality rate and transmitted mainly by Hyalomma marginatum. The geographical distribution of H. marginatum covers most of the Western Mediterranean basin. We aimed to investigate whether CCHF virus (CCHFv is circulating in Tunisia. Samples from unexplained acute febrile patients (n = 181 and a high risk group of humans, mainly slaughter workers (n = 38, were collected in the summer of 2014 and analyzed for exposure to CCHFv using serological tests and real-time RT-PCR. Ticks were collected from Northern and Southern Tunisia during May–June 2014 and examined for the presence of CCHFv by real-time RT-PCR. Of the 181 febrile patients, 5 showed only high titers of IgM suggesting a recent exposure to CCHFv. Among 38 slaughter workers, 2 had IgG anti-CCHFv responses yielding a seroprevalence of 5.2%. No CCHFv was detected in ticks and sera. Our results provide evidence of human exposure to CCHFv in Tunisia.

  18. Refugees in and out North Africa: a study of the Choucha refugee camp in Tunisia.

    Science.gov (United States)

    Dourgnon, Paul; Kassar, Hassène

    2014-08-01

    In recent years, North African (NA) countries ceased to be emigration-only countries and are now on the verge of becoming immigration as well as transit countries for economic migrants and refugees. Contextual as well as structural long-term factors are driving these changes. The ongoing crises in Africa and the Middle East are prompting strong outflows of refugees, which are likely to induce NA countries to share some common public policy and public health concerns with European countries in a near future. This article highlights some aspects of these changes, from the study of the consequences of the 2011 Libyan crisis in Tunisia. It addresses individual trajectories and health concerns of refugees in and out North Africa from a study of the Choucha camp in Tunisia. The camp opened to immigrants from Libya during the 2011 crisis and accommodated the bulk of the refugees flow to Tunisia until July 2012. The study includes a monographic approach and a qualitative survey in the Choucha camp refugees. We describe the crisis history and the health response with a focus on the camp. We then address refugees' trajectories, and health needs and concerns from the interviews we collected in the camp in April 2012. © The Author 2014. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

  19. Reproductive Health Policy in Tunisia: Women's Right to Reproductive Health and Gender Empowerment.

    Science.gov (United States)

    Amroussia, Nada; Goicolea, Isabel; Hernandez, Alison

    2016-12-01

    Although Tunisia is regarded as a pioneer in the Middle East and North Africa in terms of women's status and rights, including sexual and reproductive health and rights, evidence points to a number of persisting challenges. This article uses the Health Rights of Women Assessment Instrument (HeRWAI) to analyze Tunisia's reproductive health policy between 1994 and 2014. It explores the extent to which reproductive rights have been incorporated into the country's reproductive health policy, the gaps in the implementation of this policy, and the influence of this policy on gender empowerment. Our results reveal that progress has been slow in terms of incorporating reproductive rights into the national reproductive health policy. Furthermore, the implementation of this policy has fallen short, as demonstrated by regional inequities in the accessibility and availability of reproductive health services, the low quality of maternal health care services, and discriminatory practices. Finally, the government's lack of meaningful engagement in advancing gender empowerment stands in the way as the main challenge to gender equality in Tunisia.

  20. Foraminiferal assemblages behavior at the Messinian-Pliocene boundary in Eastern Tunisia

    Science.gov (United States)

    Gaaloul, Nadia; Rim, Temami; Razgallah, Saloua

    2014-05-01

    The microfaunal study of several boreholes drilled in Eastern Tunisia (western edge of the Mediterranean pelagian platform) has allowed the characterization of the Miocene-Pliocene boundary which has been previously well studied elsewhere in the Mediterranean basins but is still to be more understood within the Tunisian Mediterranean margin. Analyses of vertical and lateral evolution of benthonic and planktonic foraminifera between five boreholes belonging to the Gulf of Hammamet (Eastern Tunisia) revealed three distinctive palaeo-ecological depositional environments. - During the lower Messinian, benthonic foraminifera are abundant and show a great diversity in genus and species. They indicate marine settings with normal salinity and good oxygenation. Sub-reefal environment characterize this shallow water limestone platform; - The Upper Messinian is characterized by a general extinction of foraminifera (only few euryhalin organisms remain at the base of these series). This event corresponds to the Messinian salinity crisis and to the accumulation of evaporites in the Mediterranean basins. In the offshore of Eastern Tunisia, gypsum and anhydrites are deposited in a lagoonal environment and had a negative effect on the biological life. - During the Pliocene, limestones and clays overlay an erosional surface corresponding to the top of the Messinian deposits. This unconformity indicates the beginning of the Pliocene transgression which has led to a high diversity in planktonic and benthonic foraminifera. This new assemblage indicates open marine conditions.