• Title/Summary/Keyword: desert

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Pedobacter xinjiangensis sp. nov., from the Desert, Xinjiang

  • Tang, Yali;Wang, Yang;Ji, Shanming;Zhang, Kundi;Dai, Jun;Zhang, Lei;Peng, Fang;Fang, Chengxiang
    • Journal of Microbiology and Biotechnology
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    • v.20 no.2
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    • pp.397-402
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    • 2010
  • A Gram-negative, rod-shaped, gliding, aerobic bacterium, designated $12157^T$, was isolated from the desert of Xinjiang, China and subjected to a polyphasic taxonomic study. The strain $12157^T$ grew optimally at pH 7.0 and $30^{\circ}C$. MK-7 was the predominant respiratory menaquinone. The DNA G+C content was 42.0 mol%. Phylogenetic analysis based on the 16S rRNA gene sequences showed that the isolate was mostly related to members of the genus Pedobacter, with similarities ranging from 90.0% to 93.7%. Phylogenetic evidence and the results of phenotypic and genotypic analyses support the establishment of a novel species, Pedobacter xinjiangensis sp. nov., with strain $12157^T$ (=CCTCC AB $208092^T$=NRRL B-$51338^T$) as the type strain.

Ab-Anbar, the Ancient Underground Water Houses of Iran

  • Yazdi, J. Tababaee;Han, Moo-Young
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.1438-1441
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    • 2008
  • Throughout the history, the people of Iran have battled the dryness by innovations to preserve every drop of water that lands from the rare clouds, or from a stream flowing out of distant springs. Water is precious and held with highest respect, whether stored for drinking at an Ab-Anbar, or for washing and farming at the Houz in the middle of their oasis homes and orchards, or sourced at a Qanat spring or Jooy under ground. How it is that drinking water as cold as a mountain fall is found in desert of Iran? Ab-Anbar is an ancient means of water preservation and cooling through anunderground building structure. These underground structures have been present in Khorasan and other desert provinces of Iran as public or private water storage facilities, widely used before the installation of public plumbing systems in the late 1950s. Although many of these structures are still functional, most have been protected by government for restoration or viewing by the public as historical heritage. Khorasan natural dry climate and the massive surrounding deserts have been a breeding ground for many designs of Ab-Anbars. Today the existing number of such facilities stands in the province of Khorasan. Usually these structures were built in populated areas, also there are some forms of such structures on old trade routes and roadways leading to and from populated towns. This paper considers the history of Ab-Anbars in Khorasan as well as other relevant aspects such as types, components, construction methods and materials, filling and withdrawal systems.

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The effects of salt stress and prime on germination improvement and seedling growth of Calotropis procera L. seeds

  • Taghvaei, Mansour;Khaef, Nazila;Sadeghi, Hossein
    • Journal of Ecology and Environment
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    • v.35 no.2
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    • pp.73-78
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    • 2012
  • $Calotropis$ $procera$ L. is a perennial shrub distributed in saline areas of deserts of South Asia. Salt stress is a very challenging subject in arid and semi-arid areas. Germination stage is very sensitive and many plants do not germinate in saline soil. The objective of this study was identifying the salinity effect on seed germination of $Calotropis$ $procera$ L. The experimental design was a complete randomized block design with NaCl and $CaCl_2$ at five levels of isobar concentrations: 0.0, -0.01, -0.05, -0.1, and -0.15 MPa. Osmotic potential had significant effects ($P$ < 0.01) on germination percentage, germination rate, shoot length, root length, and seedling dry weight. All seedling characteristics decreased with decrease in osmotic potential. Shoot length and root length decreased more than the seedling characteristics. Germination was completely inhibited in -0.1 Mpa. Priming with NaCl and $CaCl_2$ (-0.1 MPa) for four days had significant effects ($P$ < 0.01) on the germination percentages. Priming improved the seedling characteristics in all samples, especially in -0.05 Mpa, but a decrease with decrease in osmotic potential.

Sam Shepard's True West Ideal and actuality (샘 셰퍼드의 "진짜 서부" : 이상과 현실)

  • Kim, In-Pyo
    • English Language & Literature Teaching
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    • v.10 no.3
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    • pp.143-157
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    • 2004
  • Sam Shepard is one of the leading American playwrights who represented Off-Off Broadway in the l960s and 1970s. In his early days, he wrote many experimental plays but later he turned to realism. However, under the superficial realism in his later plays, we find that they contain experimental devices and themes. True West (1980) is the last play of ills realistic family trilogy. This play shows that the tradition of Old West, which is symbolized and replaced by desert, disappeared in the industrialized clues of modern West. The Old West is compared which the modern West through the struggle of two brothers, Lee and Austin. Their father, 'Old Man', ran out on his family and went to the desert but did not succeed there. He shows that he failed in achieving the American Dream. The family appears unusual and demolished The relationships of the characters are not based on love and belief. The family symbolizes the negative aspects of modern American society. After Austin recognizes the actual situation finding that there is no real life in the modern West, he tries to leave the city and his family. He wants to go to the desert in search of a new life. However, in the last tableau Lee blocks the exit and the two brothers square off. It implies that they are doomed to continue their struggle. The message Implies that American society today is lacking the same positive values they once had in the Old West.

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Analysis of Some Desert Ecosystems Vegetation in Abu Dhabi Emirate, United Arab Emirates. Effect of Land Use

  • Mousa, Mohamed Taher;Ksiksi, Taoufik Salah
    • Journal of Forest and Environmental Science
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    • v.25 no.1
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    • pp.49-55
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    • 2009
  • The present study analyses the effect of land use on the vegetation of some desert ecosystems in Abu Dhabi, United Arab Emirates (UAE). Three sites were selected to represent different types of land use, inside Umm Al-Banadeq forest, outside the forest and along Abu Dhabi-Al Ain Trucks Road. In total, fifty-two stands were examined; including a matrix of 14 species ${\times}$ 52 stands. Based on species cover data, stands were classified using TWINSPAN and ordinated using DCA. Four vegetation groups were generated at level three of classification. Zygophyllum mandavillei was dominant in most vegetation groups; Heliotropium bacciferum dominated vegetation groups inhabited the forest. Species richness, species turnover, relative evenness and relative concentration of dominance of forest vegetation groups were 2.8, 5.7, 0.7, and 2.0, respectively. The differences were attributed to both natural variability and forestry-induced changes, including change in land use, drainage and ploughing and shading by trees. Vegetation group inhabited Abu Dhabi-Al Ain Trucks Road, that were dominated by Haloxylon salicornicum and Zygophyllum mandavillei have high total cover (8.8 m per $m^{-1}$). Most community and vegetation attributes were significantly higher inside the forest than outside. Human interventions and environmental factors affected species diversity and abundance of these communities.

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DEVELOPING A VISIBLE CHANNEL CALIBRATION ALGORITHM FOR COMS OVER OCEAN AND DESERT TARGETS

  • Sohn, B.J.;Chun, Hyoung-Wook;Kim, Jung-Geun
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.53-56
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    • 2007
  • The Korean Geostationary satellite (COMS) to fly in year 2009 will carry a meteorological sensor from which visible channel measurements will be available. We developed a method utilizing satellite-derived BRDFs for the solar channel calibration over the bright desert area. The 6S model has been incorporated to account for directional effects of the surface using MODIS-derived BRDF parameters within the spectral interval in interest. Simulated radiances over the desert targets were compared with MODIS and SeaWiFS measured spectral radiances in order to examine the feasibility of the developed calibration algorithm. We also simulated TOA radiance over ocean targets to verify the consistency and reliability of the result. It was shown that simulated 16-day averaged radiances are in good agreement with the satellite-measured radiances within about ${\pm}5%$ uncertainty range for the year 2005, suggesting that the developed algorithm can be used for calibrating the COMS visible channel within about 5% uncertainty level.

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Multi-Dimension Scaling as an exploratory tool in the analysis of an immersed membrane bioreactor

  • Bick, A.;Yang, F.;Shandalov, S.;Raveh, A.;Oron, G.
    • Membrane and Water Treatment
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    • v.2 no.2
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    • pp.105-119
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    • 2011
  • This study presents the tests of an Immersed Membrane BioReactor (IMBR) equipped with a draft tube and focuses on the influence of hydrodynamic conditions on membrane fouling in a pilot-scale using a hollow fiber membrane module of ZW-10 under ambient conditions. In this system, the cross-flow velocities across the membrane surface were induced by a cylindrical draft-tube. The relationship between cross-flow velocity and aeration strength and the influence of the cross-flow on fouling rate (under various hydrodynamic conditions) were investigated using Multi-Dimension Scaling (MDS) analysis. MDS technique is especially suitable for samples with many variables and has relatively few observations, as the data about Membrane Bio-Reactor (MBR) often is. Observations and variables are analyzed simultaneously. According to the results, a specialized form of MDS, CoPlot enables presentation of the results in a two dimensional space and when plotting variables ratio (output/input) rather than original data the efficient units can be visualized clearly. The results indicate that: (i) aeration plays an important role in IMBR performance; (ii) implementing the MDS approach with reference to the variables ratio is consequently useful to characterize performance changes for data classification.

Log-based petrophysical analysis of Khatatba Formation in Shoushan Basin, North Western Desert, Egypt

  • Osli, Liyana Nadiah;Yakub, Nur Yusrina;Shalaby, Mohamed Ragab;Islam, Md. Aminul
    • Geosciences Journal
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    • v.22 no.6
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    • pp.1015-1026
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    • 2018
  • This paper aims to investigate the good reservoir quality and hydrocarbon potentiality of the Khatatba Formation, Qasr Field in the Shoushan Basin of the North Western Desert, Egypt by combining results from log-based petrophysical analysis, petrographic description and images from scanning electron microscope (SEM). Promising reservoir units are initially identified and evaluated through well log analysis of three wells in the field of study. Petrophysical results are then compared with petrographic and SEM images from rock samples to identify features that characterize the reservoir quality. Well log results show that Khatatba Formation in the study area has good sandstone reservoir intervals from depths ranging from 12848 ft to 13900 ft, with good effective porosity records of 13-15% and hydrocarbon saturations of greater than 83%. Petrographic analysis of these sandstone reservoir units indicate high concentrations of vacant pore spaces with good permeability that can be easily occupied by hydrocarbon. The availability of these pore spaces are attributed to pore-enhancing diagenetic features, mainly in the form of good primary porosity and dissolution. SEM images and EDX analysis confirmed the presence of hydrocarbon, therefore indicating a good hydrocarbon-storing potential for the Khatatba Formation sandstones.

Identification of Source Locations for Atmospheric Dry Deposition of Heavy Metals during Yellow-Sand Events in Seoul, Korea in 1998 Using Hybrid Receptor Models

  • Han, Young-Ji;Holsen, Thomas M.;Hopke, Philip K.;Cheong, Jang-Pyo;Kim, Ho;Yi, Seung-Muk
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2004.06a
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    • pp.92-106
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    • 2004
  • Elemental dry deposition fluxes were measured using dry deposition plates from March to June 1998 in Seoul, Korea. During this spring sampling period several yellow sand events characterized by long-range transport from China and Mongolia impacted the area. Understanding the impact of yellow-sand events on atmospheric dry deposition is critical to managing the heavy metal levels in the environment in Korea. In this study, the measured flux of a primarily crustal metal, Al and an anthropogenic metal, Pb was used with two hybrid receptor models, potential source contribution function (PSCF) and residence time weighted concentration (RTWC) for locating sources of heavy metals associated with atmospheric dry deposition fluxes during the yellow-sand events in Seoul, Korea. The PSCF using a criterion value of the 75th percentile of the measured dry deposition fluxes and RTWC results using the measured elemental dry deposition fluxes agreed well and consistently showed that there were large potential source areas in the Gobi Desert in China and Mongolia and industrial areas near Tianjin, Tangshan, and Shenyang in China. Major industrial areas of Shenyang, Fushun, and Anshan, the Central China loess plateau, the Gobi Desert, and the Alaskan semi-desert in China were identified to be major source areas for the measured Pb flux in Seoul, Korea. For Al, the main industrial areas of Tangshan, Tianjin and Beijing, the Gobi Desert, the Alashan semi-desert, and the Central China loess plateau were found to be the major source areas. These results indicate that both anthropogenic sources such as industrial areas and natural sources such as deserts contribute to the high dry deposition fluxes of both Pb and Al in Seoul, Korea during yellow-sand events. RTWC resolved several high potential source areas. Modeling results indicated that the long-range transport of Al and Pb from China during yellow-sand events as well as non yellow-sand spring daytimes increased atmospheric dry deposition of heavy metals in Korea.

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Study on Radiometric Variability of the Sonoran Desert for Vicarious Calibration of Satellite Sensors (위성센서 대리 검보정을 위한 소노란 사막의 복사 가변성 연구)

  • Kim, Wonkook;Lee, Sanghoon
    • Korean Journal of Remote Sensing
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    • v.29 no.2
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    • pp.209-218
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    • 2013
  • The Sonoran Desert, which is located in North America, has been frequently used for vicarious calibration of many optical sensors in satellites. Although the desert area has good conditions for vicarious calibration (e.g. high reflectance, little vegetation, large area, low precipitation), its adjacency to the sea and large variability in atmospheric water vapor are the disadvantages for vicarious calibration. For vicarious calibration using top-of-atmospheric (TOA) reflectance, the atmospheric variability brings about degraded precision in vicarious calibration results. In this paper, the location with the smallest radiometric variability in TOA reflectance is sought by using 12-year Landsat 5 data, and corrected the TOA reflectance for bidirectional reflectance distribution function (BRDF) which is another major source of variability in TOA reflectance. Experiments show that the mid-western part of the Sonoran Desert has the smallest variability collectively for visible and near-infrared bands, and the variability from the sunarget-sensor geometry can be reduced by the BRDF correction for the visible bands, but not sufficiently for the infrared bands.