WorldWideScience

Sample records for saline desert water

  1. Deficit irrigation of a landscape halophyte for reuse of saline waste water in a desert city

    Science.gov (United States)

    Glenn, E.P.; Mckeon, C.; Gerhart, V.; Nagler, P.L.; Jordan, F.; Artiola, J.

    2009-01-01

    Saline waste waters from industrial and water treatment processes are an under-utilized resource in desert urban environments. Management practices to safely use these water sources are still in development. We used a deeprooted native halophyte, Atriplex lentiformis (quailbush), to absorb mildly saline effluent (1800 mg l-1 total dissolved solids, mainly sodium sulfate) from a water treatment plant in the desert community of Twentynine Palms, California. We developed a deficit irrigation strategy to avoid discharging water past the root zone to the aquifer. The plants were irrigated at about one-third the rate of reference evapotranspiration (ETo) calculated from meteorological data over five years and soil moisture levels were monitored to a soil depth of 4.7 m at monthly intervals with a neutron hydroprobe. The deficit irrigation schedule maintained the soil below field capacity throughout the study. Water was presented on a more or less constant schedule, so that the application rates were less than ETo in summer and equal to or slightly greater than ETo in winter, but the plants were able to consume water stored in the profile in winter to support summer ET. Sodium salts gradually increased in the soil profile over the study but sulfate levels remained low, due to formation of gypsum in the calcic soil. The high salt tolerance, deep roots, and drought tolerance of desert halophytes such as A. lentiformis lend these plants to use as deficit-irrigated landscape plants for disposal of effluents in urban setting when protection of the aquifer is important. ?? 2008 Elsevier B.V.

  2. Studies of marine macroalgae: saline desert water cultivation and effects of environmental stress on proximate composition. Final subcontract report. [Gracilaria tikvahiae; Ulva lactuca

    Energy Technology Data Exchange (ETDEWEB)

    Ryther, J.H.; DeBusk, T.A.; Peterson, J.E.

    1985-11-01

    The results presented in this report address the growth potential of marine macroalgae cultivated in desert saline waters, and the effects of certain environmental stresses (e.g., nitrogen, salinity, and temperature) on the proximate composition of several marine macroalgae. Two major desert saline water types were assayed for their ability to support the growth of Gracilaria, Ulva, and Caulerpa. Both water types supported short term growth, but long term growth was not supported. Carbohydrate levels in Gracilaria were increased by cultivation under conditions of high salinity, low temperature, and low nitrogen and phosphorous availability. Data suggests that it may be possible to maximize production of useful proximate constituents by cultivating the algae under optimum conditions for growth, and then holding the resulting biomass under the environmental conditions which favor tissue accumulation of the desired storage products. 16 refs., 21 figs., 19 tabs.

  3. Soil microbial diversity, site conditions, shelter forest land, saline water drip-irrigation, drift desert.

    Science.gov (United States)

    Jin, Zhengzhong; Lei, Jiaqiang; Li, Shengyu; Xu, Xinwen

    2013-10-01

    Soil microbes in forest land are crucial to soil development in extreme areas. In this study, methods of conventional culture, PLFA and PCR-DGGE were utilized to analyze soil microbial quantity, fatty acids and microbial DNA segments of soils subjected to different site conditions in the Tarim Desert Highway forest land. The main results were as follows: the soil microbial amount, diversity indexes of fatty acid and DNA segment differed significantly among sites with different conditions (F 84%), followed by actinomycetes and then fungi (Desert Highway shelter-forest promoted soil biological development; however, for enhancing sand control efficiency and promoting sand development, we should consider the effects of site condition in the construction and regeneration of shelter-forest ecological projects. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Characteristics of moisture and salinity of soil in Taklimakan Desert, China.

    Science.gov (United States)

    Wang, Zhimin; Li, Guomin; Li, Xue; Shan, Shuo; Zhang, Jiangyi; Li, Shengyu; Fan, Jinglong

    2012-01-01

    The Taklimakan desert is known as the largest dunefield in China and also as the world's second largest shifting sand desert. The Tarim Desert Highway, which is the first highway to cross the Taklimakan desert, was built for the purpose of oil and gas resources extraction in the Tarim area, as well as for the development of the southern area of the Xinjiang Uygur Autonomous Region. Shelterbelts have been planted along the highway to prevent shifting sand from burying the road. This paper analyzes the variations of moisture and salinity of the unirrigated desert soil under natural conditions in the center of Taklimakan Desert. A number of important findings indicating the moisture and salinity of the soil at capillary saturation zone were determined by the groundwater and related to the evaporation on the top. Salinity could be affected by vegetation, which was different from moisture in the soil. Meanwhile, clay layer played an important role in water preservation in the soil, which was also beneficial to the accumulation of salinity in soil. Compared with clay layer, vegetation was a decisive factor for the gathering of salinity. The findings were significant for reasonable adjustment of irrigation in the shelterbelts for the further development of the Tarim Desert Highway.

  5. Spatiotemporal Distribution of Soil Moisture and Salinity in the Taklimakan Desert Highway Shelterbelt

    Directory of Open Access Journals (Sweden)

    Yuan Huang

    2015-08-01

    Full Text Available Salinization and secondary salinization often appear after irrigation with saline water. The Taklimakan Desert Highway Shelterbelt has been irrigated with saline ground water for more than ten years; however, soil salinity in the shelterbelt has not been evaluated. The objective of this study was to analyze the spatial and temporal distribution of soil moisture and salinity in the shelterbelt system. Using a non-uniform grid method, soil samples were collected every two days during one ten-day irrigation cycle in July 2014 and one day in spring, summer, and autumn. The results indicated that soil moisture declined linearly with time during the irrigation cycle. Soil moisture was greatest in the southern and eastern sections of the study area. In contrast to soil moisture, soil electrical conductivity increased from 2 to 6 days after irrigation, and then gradually decreased from 6 to 8 days after irrigation. Soil moisture was the greatest in spring and the least in summer. In contrast, soil salinity increased from spring to autumn. Long time drip-irrigation with saline groundwater increased soil salinity slightly. The soil salt content was closely associated with soil texture. The current soil salt content did not affect plant growth, however, the soil in the shelterbelt should be continuously monitored to prevent salinization in the future.

  6. Water and water quality management in the cholistan desert

    International Nuclear Information System (INIS)

    Kahlown, M.A.; Chaudhry, M.A.

    2005-01-01

    Water scarcity is the main problem in Cholistan desert. Rainfall is scanty and sporadic and groundwater is saline in most of the area. Rainwater is collected in man made small storages, locally called tobas during rainy season for human and livestock consumption. These tobas usually retain rainwater for three to four months at the maximum, due to small storage capacity and unfavorable location. After the tobas become dry, people use saline groundwater for human and livestock consumption where marginal quality groundwater is available. In complete absence of water they migrate towards canal irrigated areas till the next rains. During migration humans and livestock suffer from hunger, thirst and diseases. In order to overcome this problem Pakistan Council of Research in Water Resources (PCRWR) has introduced improved designs of tobas. The PCRWR is collecting more than 13.0 million cubic meter rainwater annually from only ninety hectare catchment area. As a result, water is available for drinking of human and livestock population as well as to wild life through out the year for the village of Dingarh in Cholistan desert. However, water collected in these tobas is usually muddy and full of impurities. To provide good quality drinking water to the residents of Cholistan, PCRWR has launched a Project under which required quantity of drinkable water will be provided at more than seventy locations by rainwater harvesting, pumping of good and marginal quality groundwater and desalination of moderately saline water through Reverse Osmosis Plants. After the completion of project, more then 380 million gallons of fresh rainwater and more than 1300 million gallons of good and marginal quality groundwater will be available annually. Intervention to collect the silt before reaching to the tobas are also introduced, low cost filter plants are designed and constructed on the tobas for purification of water. (author)

  7. Ground-water quality and geochemistry, Carson Desert, western Nevada

    Science.gov (United States)

    Lico, Michael S.; Seiler, R.L.

    1994-01-01

    Aquifers in the Carson Desert are the primary source of drinking water, which is highly variable in chemical composition. In the shallow basin-fill aquifers, water chemistyr varies from a dilute calcium bicarbonate-dominated water beneath the irrigated areas to a saline sodium chloride- dominated water beneath unirrigated areas. Water samples from the shallow aquifers commonly have dissolved solids, chloride, magnesium, sulfate, arsenic, and manganese concentrations that exceed State of Nevada drinking-water standards. Water in the intermediante basin-fill aquifers is a dilute sodium bicarbonate type in the Fallon area and a distinctly more saline sodium chloride type in the Soda Lake-Upsal Hogback area. Dissolved solids, chloride, arsenic, fluoride, and manganese concen- trations commonly exceed drinking-water standards. The basalt aquifer contains a dilute sodium bicarbonate chloride water. Arsenic concentrations exceed standards in all sampled wells. The concen- trations of major constituents in ground water beneath the southern Carson Desert are the result of evapotranspiration and natural geochemical reactions with minerals derived mostly from igneous rocks. Water with higher concentrations of iron and manganese is near thermodynamic equilibrium with siderite and rhodochrosite and indicates that these elements may be limited by the solubility of their respective carbonate minerals. Naturally occurring radionuclides (uranium and radon-222) are present in ground water from the Carson Desert in concen- tratons higher than proposed drinking-water standards. High uranium concentrations in the shallow aquifers may be caused by evaporative concentration and the release of uranium during dissolution of iron and manganese oxides or the oxidation of sedimentary organic matter that typically has elevated uranium concentrations. Ground water in the Carson Desert does not appear to have be contaminated by synthetic organic chemicals.

  8. Divining Jordan's desert waters | IDRC - International Development ...

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

    To most people, a desert — by definition — is a place where water is practically nonexistent. But a team of researchers studying Jordan's badia — a large desert in the country's northwest corner — has uncovered a secret moving slowly beneath the area's vast arid expanses. Using satellite photos, knowledge of the local ...

  9. Impact of highly saline wetland ecosystem on floral diversity of the Cholistan desert

    International Nuclear Information System (INIS)

    Gill, A.H.; Ahmad, K.S.; Habib, S.; Ahmad, S.A.; Nawaz, T.; Ahmad, F.

    2012-01-01

    The impact of highly saline wetland ecosystem created under Salinity Control and Reclamation Project (SCARP) on floral diversity was investigated in the arid environments of Cholistan Desert. Species richness, diversity indices and evenness indices were worked out to look at the distance at which the salt water has altered the native vegetation. Four sites including SCARP ponds of different ages (S1, S2, S3 and S4), and a reference site (SR) were selected for vegetation studies and data were recorded by 1 x 1 m quadrats, which were laid on permanent transect lines. Salt water showed great influence on ecological parameters of the native vegetation up to 40 m. Multivariate (cluster) analysis showed close clustering of highly salt tolerant species, Aeluropus lagopoides, Tamarix dioica and Suaeda fruticosa in one group, and relatively less tolerant Crotalaria burhia, Cyperus conglomeratus, Indigofera argentea, Haloxylon salicornicum, Haloxylon stocksii, Neurada procumbens and Salsola baryosma in second group. Moderately salt tolerant Aristida adscensionis, Lasiurus scindicus and Sporobolus iocladus were clustered in a separate group. (author)

  10. Effect of Salinity on Chlorophyll Fluorescence and Chlorophyll Content of the Desert Shrub Calotropis procera

    OpenAIRE

    , A. Akhkha; , T. Boutraa

    2010-01-01

    The effect of salinity stress on the efficiency of the photosynthetic apparatus in the desert shrub Calotropis procera Aiton (family: Asclepiadaceae) was investigated using chlorophyll fluorescence technique. This technique allowed the determination of a number of chlorophyll fluorescence parameters such as initial fluorescence Fo, maximum fluorescence Fm and variable fluorescence Fv. Furthermore, the effect of salinity stress on other chlorophyll fluorescence parameters (Fv / Fo and Fv / Fm ...

  11. Saline water irrigation for crop production

    International Nuclear Information System (INIS)

    Khan, A.R.; Singh, S.S.; Singh, S.R.

    2001-05-01

    Salinity is one of agriculture's most complex production problems. Excessive salts from irrigation water or high water tables can severely limit crop production. Years of saline water irrigation on poorly drained soils can eventually make economic crop production impossible. About 10% of all land are affected by salinity problems. They occur in every continent in different proportions, more frequently in arid and semi-arid areas. This paper discusses a range of problems related to use of saline water for crop irrigation

  12. Physiological response of Cucurbita pepo var. pepo mycorrhized by Sonoran desert native arbuscular fungi to drought and salinity stresses.

    Science.gov (United States)

    Harris-Valle, Citlalli; Esqueda, Martín; Gutiérrez, Aldo; Castellanos, Alejandro E; Gardea, Alfonso A; Berbara, Ricardo

    Plants response to symbiosis with arbuscular mycorrhizal fungi (AMF) under water stress is important to agriculture. Under abiotic stress conditions native fungi are more effective than exotics in improving plant growth and water status. Mycorrhization efficiency is related to soil fungi development and energy cost-benefit ratio. In this study, we assessed the effect on growth, water status and energy metabolism of Cucurbita pepo var. pepo when inoculated with native AMF from the Sonoran desert Mexico (mixed isolate and field consortium), and compared with an exotic species from a temperate region, under drought, low and high salinity conditions. Dry weights, leaf water content, water and osmotic potentials, construction costs, photochemistry and mycorrhization features were quantified. Under drought and low salinity conditions, the mixed isolate increased plant growth and leaf water content. Leaf water potential was increased only by the field consortium under drought conditions (0.5-0.9MPa). Under high salinity, the field consortium increased aerial dry weight (more than 1g) and osmotic potential (0.54MPa), as compared to non-mycorrhized controls. Plants inoculated with native AMF, which supposedly diminish the effects of stress, exhibited low construction costs, increased photochemical capacity, and grew larger external mycelia in comparison to the exotic inoculum. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  13. SUBSURFACE SEQUENCE DELINEATION AND SALINE WATER ...

    African Journals Online (AJOL)

    The driller's lithological logs aided by gamma and resistivity logs, showed that the area is underlain by clays, sandy/silty clays, clayey sands and sands with shale and limestone in places. The resistivity logs delineate saline water at shallow depth at Lekki wells I and II, Lakowe and Akodo with fresh/saline water interface at ...

  14. Microbial biodiversity in saline shallow lakes of the Monegros Desert, Spain.

    Science.gov (United States)

    Casamayor, Emilio O; Triadó-Margarit, Xavier; Castañeda, Carmen

    2013-09-01

    The Monegros Desert contains one of the largest sets of inland saline lakes in Europe constituting a threatened landscape of great scientific and ecological value with large number of reported endemisms. We analyzed bacteria, archaea, and microbial eukaryotes from 11 saline lakes in winter and spring by rRNA gene fingerprinting and sequencing covering large salinity (2.7-22.1%) and temperature ranges (1.5-35.3 °C). The highest ecological diversity (Shannon-Weaver index) was found in protists and the lowest in Archaea. Eukaryotes showed higher ecological diversity at intermediate salinities, whereas Bacteria and Archaea did not. The genetic diversity was broad and with remarkable novelty. The highest novelty was found in Archaea at the lowest saline concentrations, whereas for bacteria and protists, no differences were observed along the gradient. Euryarchaeota of the enigmatic group DHVEG-6 and phylotypes distantly related to well-known haloarchaea were present in several sites. Recurrent presence of bacterial phylotypes distantly related to Psychroflexus and Cryomorphaceae initially isolated from polar marine habitats was observed. Saline lakes contained chlorophyta, among other new groups, substantially different from green algae previously reported in marine or freshwater. The great scientific and ecological value found for macroorganisms can be extended to the idiosyncratic microorganisms inhabiting such unique habitat in Europe. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  15. Fog water chemistry in the Namib desert, Namibia

    Science.gov (United States)

    Eckardt, Frank D.; Schemenauer, Robert S.

    This study documents the ion concentrations and ion enrichment relative to sea water, in Namib Desert fog water, with the purpose of establishing its suitability for future fogwater collection schemes, while also examining claims that Namib Desert fog water carries exceptionally high concentrations of sulphate, which may be responsible for the formation of gypsum deposits in the desert. The work suggests that Namibian fog water is at least as clean as has been reported from other coastal deserts in South America and Arabia, and provides a source of very clean water for the coastal desert region of south-western Africa. It does not appear that fog is an efficient sulphur source for the formation of the gypsum deposits, unless rare events with high concentrations of marine sulphur compounds occur.

  16. The diversity and abundance of bacteria and oxygenic phototrophs in saline biological desert crusts in Xinjiang, northwest China.

    Science.gov (United States)

    Li, Ke; Liu, Ruyin; Zhang, Hongxun; Yun, Juanli

    2013-07-01

    Although microorganisms, particularly oxygenic phototrophs, are known as the major players in the biogeochemical cycles of elements in desert soil ecosystems and have received extensive attention, still little is known about the effects of salinity on the composition and abundances of microbial community in desert soils. In this study, the diversity and abundance of bacteria and oxygenic phototrophs in biological desert crusts from Xinjiang province, which were under different salinity conditions, were investigated by using clone library and quantitative PCR (qPCR). The 16S rRNA gene phylogenetic analysis showed that cyanobacteria, mainly Microcoleus vagnitus of the order Oscillatoriales, were predominant in the low saline crusts, while other phototrophs, such as diatom, were the main microorganism group responsible for the oxygenic photosynthesis in the high saline crusts. Furthermore, the higher salt content in crusts may stimulate the growth of other bacteria, including Deinococcus-Thermus, Bacteroidetes, and some subdivisions of Proteobacteria (β-, γ-, and δ-Proteobacteria). The cpcBA-IGS gene analysis revealed the existence of novel M. vagnitus strains in this area. The qPCR results showed that the abundance of oxygenic phototrophs was significantly higher under lower saline condition than that in the higher saline crusts, suggesting that the higher salinity in desert crusts could suppress the numbers of total bacteria and phototrophic bacteria but did highly improve the diversity of salt-tolerant bacteria.

  17. Saline water irrigation of quinoa and chickpea

    DEFF Research Database (Denmark)

    Hirich, A.; Jelloul, A.; Choukr-Allah, R.

    2014-01-01

    A pot experiment was conducted in the south of Morocco to evaluate the response of chickpea and quinoa to different irrigation water salinity treatments (1, 4, 7 and 10 dS m-1 for chickpea and 1, 10, 20 and 30 dS m-1 for quinoa). Increasing salinity affected significantly (P ... and height and caused delay and reduction in seed emergence, quinoa was shown to be more resistant than chickpea. Dry biomass, seed yield, harvest index and crop water productivity were affected significantly (P ... and seed yield for both quinoa and chickpea while increasing salinity resulted in increase - in the case of quinoa - and decrease - in the case of chickpea - in harvest index and crop water productivity. Na+ and Na+/K+ ratio increased with increasing irrigation water salinity, while K+ content decreased...

  18. Ground-water data, Sevier Desert, Utah

    Science.gov (United States)

    Mower, Reed W.; Feltis, Richard D.

    1964-01-01

    This report is intended to serve two purposes: (1) to make available to the public basic ground-water data useful in planning and studying development of water resources, and (2) to supplement an interpretive report that will be published later.Records were collected during the period 1935-64 by the U.S. Geological survey in cooperation with the Utah State Engineer as part of the investigation of ground-water conditions in the Sevier Desert, in Juab and Millard Counties, Utah. The interpretive material will be published in a companion report by R. W. Mower and R. D. Feltis.This report is most useful in predicting conditions likely to be found in areas that are being considered as well sites. The person considering the new well can spot the proposed site on plate 1 and examine the records of nearby wells as shown in the tables and figures. From table 1 he can note such things as depth, diameter, water level, yield, use of water, temperature of water, and depth of perforations. By comparing the depth of perforations with the drillers' logs in table 3 he can note the type of material that yields water to the wells. Table 2 and figure 2 show the historic fluctuations and trends of water levels in the vicinity. From table 4 he can note the chemical quality of the water from wells in the vicinity. Table 5 shows the amount of water discharged during 1951-63 from the pumped irrigation, public supply, and industrial wells. If the reader decides from his examination that conditions are favorable, he can place an application to drill a well with the state Engineer. If the State Engineer believes unappropriated water is available, the application may be approved after minimum statutory requirements have been satisfied.The report is also useful when planning large-scale developments of water supply. This and other uses of the report will be helped by use of the interpretive report upon its release.

  19. Negev: Land, Water, and Life in a Desert Environment

    Science.gov (United States)

    Back, William

    In view of the continuing increased concern about the extreme fragility of deserts and desert margins, Negev provides a timely discussion of land-use practices compatible with the often conflicting goals of preservation and development. The success o f agricultural and hydrologic experiments in the Negev desert of Israel offers hope to the large percentage of the world's population that lives with an unacceptably low quality of life in desert margins. Deserts are the one remaining type of open space that, with proper use, has the potential for alleviating the misery often associated with expanding population.In addition to the science in the book, the author repeatedly reinforces the concept that “western civilization is inextricably bound to the Negev and its environs, from which it has drawn, via its desert-born religions—Judasium, Christianity, and Islam—many of the mores and concepts, and much of the imagery and love of the desert, including man's relation to nature and to ‘God’.” Deserts often are erroneously perceived to be areas of no water: In reality, these are areas in which a little rainfall occurs sporadically and unpredictably over time. This meager water supply can be meticulously garnered to produce nutritious crops and forage.

  20. Deserts

    Science.gov (United States)

    Belnap, Jayne; Webb, Robert H.; Esque, Todd; Brooks, Matthew L.; DeFalco, Lesley; MacMahon, James A.

    2016-01-01

    The deserts of California (Lead photo, Fig. 1) occupy approximately 38% of California’s landscape (Table 1) and consist of three distinct deserts: the Great Basin Desert, Mojave Desert, and Colorado Desert, the latter of which is a subdivision of the Sonoran Desert (Brown and Lowe 1980). The wide range of climates and geology found within each of these deserts result in very different vegetative communities and ecosystem processes and therefore different ecosystem services. In deserts, extreme conditions such as very high and low temperatures and very low rainfall result in abiotic factors (climate, geology, geomorphology, and soils) controlling the composition and function of ecosystems, including plant and animal distributions. This is in contrast to wetter and milder temperatures found in other ecosystems, where biotic interactions are the dominant driving force. However, despite the harsh conditions in deserts, they are home to a surprisingly large number of plants and animals. Deserts are also places where organisms display a wide array of adaptations to the extremes they encounter, providing some of the best examples of Darwinian selection (MacMahon and Wagner 1985, Ward 2009). Humans have utilized these regions for thousands of years, despite the relatively low productivity and harsh climates of these landscapes. Unlike much of California, most of these desert lands have received little high-intensity use since European settlement, leaving large areas relatively undisturbed. Desert landscapes are being altered, however, by the introduction of fire following the recent invasion of Mediterranean annual grasses. As most native plants are not fire-adapted, they Many do not recover, whereas the non-native grasses flourish. Because desert lands are slow to recover from disturbances, energy exploration and development, recreational use, and urban development will alter these landscapes for many years to come. This chapter provides a brief description of where the

  1. CROP DENSITY AND IRRIGATION WITH SALINE WATER

    OpenAIRE

    Feinerman, Eli

    1983-01-01

    The economic implications of plant density for irrigation water use under saline conditions are investigated, utilizing the involved physical and biological relationships. The analysis considers a single crop and is applied to cotton data. The results suggest that treating plant density as an endogenous control variable has substantial impact on profits and the optimal quantities and qualities of the applied irrigation water.

  2. Dwarf cashew growth irrigated with saline waters

    Directory of Open Access Journals (Sweden)

    Hugo Orlando Carvallo Guerra

    2009-12-01

    Full Text Available The cashew production is one of the most important agricultural activities from the social-economical viewpoint for the North East of Brazil; besides to produce a great deal of hand labor, it is very important as an exporting commodity. The inadequate use of irrigation in the semi arid regions of the North East of Brazil has induced soil salinization and consequently problems for the irrigated agriculture. In spite of this, few works have been conducted to study the effect of saline stress on the growth and development of the cashew. Because of the lack of information for this crop, an experiment was conducted to study the effect of salinity stress on the phytomass production and nutrient accumulation on the different organs of the precocious dwarf cashew (Anacardium occidentale L. clone CCP76. The study was conducted under controlled conditions using as statistical scheme a randomized block design factorial with six replicates. Five salinity treatments were considered for the irrigation water (electrical conductivities of 0.8, 1.6, 2.4, 3.2 and 4.0 dS m-1 at 25oC. The increasing in salinity of the irrigation water reduced the phytomass at different organs of the studied plant. The nitrogen, phosphorus, potassium, chloride and sodium in the plant varied with the salinity of the irrigation water according with the part of the plant analyzed; in some parts increased, in others decreased, in others increased initially and decreased afterwards, and finally, in other part of the plant the salinity of the irrigation water did not affect the nutrient concentration.

  3. Tritium water as a marker for the measurement of body water turnover rates in desert livestock, rodent and bird species

    International Nuclear Information System (INIS)

    Khan, M.S.; Ghosh, P.K.; Bohra, R.C.

    1990-01-01

    Tritiated water has been used for estimating body water turnover rates (BWTRs) in desert livestock, rodent and birds. BWTRs in relation to adaption of these animal species to desert environment have been discussed. (author). 5 refs., 2 tabs

  4. Soil Fertility, Salinity and Nematode Diversity Influenced by Tamarix ramosissima in Different Habitats in an Arid Desert Oasis

    Science.gov (United States)

    Yong-zhong, Su; Xue-fen, Wang; Rong, Yang; Xiao, Yang; Wen-jie, Liu

    2012-08-01

    The aim of this paper was to assess the influence of tamarisk shrubs on soil fertility, salinity and nematode communities in various habitats located in an arid desert-oasis region in northwest China. Three habitats were studied: sand dune, riparian zone and saline meadow, where tamarisk shrubs have been established in recent decades in order to vegetation restoration used as desertification control and saline land rehabilitation projects and become the dominant plant community. The parameters measured include soil organic carbon (SOC), total nitrogen, available phosphorus (P) and potassium (K), pH, salt component, and nematode community characteristics. Enrichment ratios (a comparison of the soil measurements between soils under canopy and in the open interspaces) for soil nutrients and salinity were used to evaluate fertility and salinity islands underneath the tamarisk shrubs. The soil nematode community was used as a biological indicator of soil condition. SOC and available P and K were higher beneath the plant canopy than in the open interspaces outside that canopy. The enrichment ratios for SOC and nutrients were highest for the sand dune habitat and tamarisk shrubs clearly created islands of greater salinity under the canopies. Nematode abundance per 100 g dry soil varied considerably between the locations and habitats, with the highest abundance found in sand dune and the lowest in saline meadow. A significantly higher nematode abundance and a lower trophic diversity were found in soils under the canopy compared to the soils in the open interspaces. With the exception of saline meadow, the abundance of bacterivores increased and fungivores decreased under the canopy relative to the open interspaces, and bacterivores dominated under the canopies in the sand dune and riparian habitats. The enrichment ratios for salinity were higher than for fertility, suggesting that improved soil fertility can not limit the impact of salinization beneath tamarisk shrubs. The

  5. Soil fertility, salinity and nematode diversity influenced by Tamarix ramosissima in different habitats in an arid desert oasis.

    Science.gov (United States)

    Yong-zhong, Su; Xue-fen, Wang; Rong, Yang; Xiao, Yang; Wen-jie, Liu

    2012-08-01

    The aim of this paper was to assess the influence of tamarisk shrubs on soil fertility, salinity and nematode communities in various habitats located in an arid desert-oasis region in northwest China. Three habitats were studied: sand dune, riparian zone and saline meadow, where tamarisk shrubs have been established in recent decades in order to vegetation restoration used as desertification control and saline land rehabilitation projects and become the dominant plant community. The parameters measured include soil organic carbon (SOC), total nitrogen, available phosphorus (P) and potassium (K), pH, salt component, and nematode community characteristics. Enrichment ratios (a comparison of the soil measurements between soils under canopy and in the open interspaces) for soil nutrients and salinity were used to evaluate fertility and salinity islands underneath the tamarisk shrubs. The soil nematode community was used as a biological indicator of soil condition. SOC and available P and K were higher beneath the plant canopy than in the open interspaces outside that canopy. The enrichment ratios for SOC and nutrients were highest for the sand dune habitat and tamarisk shrubs clearly created islands of greater salinity under the canopies. Nematode abundance per 100 g dry soil varied considerably between the locations and habitats, with the highest abundance found in sand dune and the lowest in saline meadow. A significantly higher nematode abundance and a lower trophic diversity were found in soils under the canopy compared to the soils in the open interspaces. With the exception of saline meadow, the abundance of bacterivores increased and fungivores decreased under the canopy relative to the open interspaces, and bacterivores dominated under the canopies in the sand dune and riparian habitats. The enrichment ratios for salinity were higher than for fertility, suggesting that improved soil fertility can not limit the impact of salinization beneath tamarisk shrubs. The

  6. Saline water in southeastern New Mexico

    Science.gov (United States)

    Hiss, W.L.; Peterson, J.B.; Ramsey, T.R.

    1969-01-01

    Saline waters from formations of several geologic ages are being studied in a seven-county area in southeastern New Mexico and western Texas, where more than 30,000 oil and gas tests have been drilled in the past 40 years. This area of 7,500 sq. miles, which is stratigraphically complex, includes the northern and eastern margins of the Delaware Basin between the Guadalupe and Glass Mountains. Chloride-ion concentrations in water produced from rocks of various ages and depths have been mapped in Lea County, New Mexico, using machine map-plotting techniques and trend analyses. Anomalously low chloride concentrations (1,000-3,000 mg/l) were found along the western margin of the Central Basin platform in the San Andres and Capitan Limestone Formations of Permian age. These low chloride-ion concentrations may be due to preferential circulation of ground water through the more porous and permeable rocks. Data being used in the study were obtained principally from oil companies and from related service companies. The P.B.W.D.S. (Permian Basin Well Data System) scout-record magnetic-tape file was used as a framework in all computer operations. Shallow or non-oil-field water analyses acquired from state, municipal, or federal agencies were added to these data utilizing P.B.W.D.S.-compatible reference numbers and decimal latitude-longitude coordinates. Approximately 20,000 water analyses collected from over 65 sources were coded, recorded on punch cards and stored on magnetic tape for computer operations. Extensive manual and computer error checks for duplication and accuracy were made to eliminate data errors resulting from poorly located or identified samples; non-representative or contaminated samples; mistakes in coding, reproducing or key-punching; laboratory errors; and inconsistent reporting. The original 20,000 analyses considered were reduced to 6,000 representative analyses which are being used in the saline water studies. ?? 1969.

  7. Water Sources for Cyanobacteria Below Desert Rocks in the Negev Desert Determined by Conductivity

    Science.gov (United States)

    McKay, Christopher P.

    2016-01-01

    We present year round meteorological and conductivity measurements of colonized hypolithic rocks in the Arava Valley, Negev Desert, Israel. The data indicate that while dew is common in the Negev it is not an important source of moisture for hypolithic organisms at this site. The dominance of cyanobacteria in the hypolithic community are consistent with predictions that cyanobacteria are confined to habitats supplied by rain. To monitor the presence of liquid water under the small Negev rocks we developed and tested a simple field conductivity system based on two wires placed about 0.5 cm apart. Based on 21 replicates recorded for one year in the Negev we conclude that in natural rains (0.25 mm to 6 mm) the variability between sensor readings is between 20 and 60% decreasing with increasing rain amount. We conclude that the simple small electrical conductivity system described here can be used effectively to monitor liquid water levels in lithic habitats. However, the natural variability of these sensors indicates that several replicates should be deployed. The results and method presented have use in arid desert reclamation programs.

  8. diurnal and seasonal water relations of the desert phreatophyte prosopis-glandulosa (honey mesquite) in the Sonoran Desert of California

    OpenAIRE

    Nilsen, E. T.; Sharifi, M. R.; Rundel, P. W.; Jarrell, W. M.; Virginia, R. A.

    1983-01-01

    Diurnal and Seasonal water relations were monitored in a population of Prosopis glandulosa var. torreyana in the Sonoran Desert of southern California. Prosopis glandulosa at this research site acquired its water from a ground water source 4-6 m deep. Measurements of diurnal and seasonal cycles of aboveground environmental conditions, soil moisture, and soil water potential (to 6 m depth) were taken to ascertain environmental water availability and water stress. Leaf water potential, leaf con...

  9. Analysis of Production-Water-Salinity of Index Crops in

    Science.gov (United States)

    Sharifan, H.; Ghahreman, B.

    2009-04-01

    One method to investigate the advantages of irrigation in cultivation is to evaluate the amount of increase in productions as a result of irrigation. Such relations which usually characterized by mathematics formulas or curves are called production to water function. In the agricultural analysis like pattern optimization and culture accumulation, we need some function like agricultural crops production, water and salinity. The amount of water used and salinity has influence on crops function, so that by increase in both components in various stages of plant growth, crop function decreases. Many researches have been performed on production-water and production-salinity function, therefore less researches on production-water-salinity components. The equation provided by Letey and Dinar (1986) is a sample of these researches. Their model is a quadratics equation from independent variables of water salinity in irrigation (ECi) and dimensionless proportion of the amount of water used to evaporation in class A (AW/EP) in plant growth stage. Therefore, by using this model and parameters like evaporation, rainfall and also quantity and quality water potential in Golestan farmlands, we obtained production-water-salinity components for each product in three different areas across Golestan province (moisture to dry areas). These products include sunflower, cotton, wheat, barely, potato, tomato, corn, sorgom, water melon, soybean and rice. Finally, these equations were compared by results of previous experiments, some results correspond and others were different. Key Word: production-water, production-salinity and production-water-salinity function, Letey and Dinar, Golestan.

  10. Hydrochemical and Isotopic Assessment of Ground Water in Eastern Desert, Egypt

    International Nuclear Information System (INIS)

    Atiti, S.Y.; Ali, M.M.; Yousef, L.A.; Dessouki, H.A.

    2011-01-01

    The recharge rate is the most critical factor to ground water resources especially in semi- arid and arid areas. Fourteen representative ground water samples were collected from South Eastern Desert of Egypt and subjected to chemical and isotopic composition. The chemical data reported that, the alkalinity (ph) ranges between 6.5 and 8.5, the salinity of water ranges between 396 and 7874 ppm, sodium is the most dominant cation and chloride is the most dominant anion. The concentration of trace elements (Fe, Pb, Cd, Ni, Cu, Zn, and Mn) was analyzed to evaluate the suitability for drinking and irrigation. Uranium and thorium concentrations were found within the safe limit. Most of ground water was found suitable for drinking water, laundry, irrigation, building, industrial, livestock and poultry. The environmental stable isotopes (D and 18 O) and the radioactive isotope 3 H were evaluated for water samples of the investigated area to focus on the origin of the ground water, sources of recharging and the water rock interaction between aquifers and water. The isotopic compositions of these ground water samples indicated that, there are three different sources of recharge; paleo-water, local precipitation and rain water

  11. Integrating water by plant roots over spatially distributed soil salinity

    Science.gov (United States)

    Homaee, Mehdi; Schmidhalter, Urs

    2010-05-01

    In numerical simulation models dealing with water movement and solute transport in vadose zone, the water budget largely depends on uptake patterns by plant roots. In real field conditions, the uptake pattern largely changes in time and space. When dealing with soil and water salinity, most saline soils demonstrate spatially distributed osmotic head over the root zone. In order to quantify such processes, the major difficulty stems from lacking a sink term function that adequately accounts for the extraction term especially under variable soil water osmotic heads. The question of how plants integrate such space variable over its rooting depth remains as interesting issue for investigators. To move one step forward towards countering this concern, a well equipped experiment was conducted under heterogeneously distributed salinity over the root zone with alfalfa. The extraction rates of soil increments were calculated with the one dimensional form of Richards equation. The results indicated that the plant uptake rate under different mean soil salinities preliminary reacts to soil salinity, whereas at given water content and salinity the "evaporative demand" and "root activity" become more important to control the uptake patterns. Further analysis revealed that root activity is inconstant when imposed to variable soil salinity. It can be concluded that under heterogeneously distributed salinity, most water is taken from the less saline increment while the extraction from other root zone increments with higher salinities never stops.

  12. Low-salinity water off West Luzon Island in summer

    Science.gov (United States)

    Yan, Yunwei; Wang, Guihua; Wang, Chunzai; Su, Jilan

    2015-04-01

    Low-salinity water with two cores is found off West Luzon Island in the South China Sea (SCS) during summer. A series of salinity observations and model results show that the low-salinity water begins to appear in June, reaches its lowest salinity in September, and disappears after October. Rainfall associated with the summer monsoon impinging on the Philippine mountain ranges plays an important role in the formation of the low-salinity water, while upward Ekman pumping of high-salinity subsurface water caused by the strong winter monsoon is important for its disappearance. Variation in mixed layer depth is responsible for the formation of the two cores of the low-salinity water, while advection also contributes. The study further demonstrates that the low-salinity water has considerable interannual variability associated with El Niño-Southern Oscillation (ENSO): during the summer of the decaying year of an El Niño, an anticyclonic wind anomaly occurs in the SCS. The anticyclonic wind anomaly is associated with a northeasterly anomaly south of 18°N, reducing precipitation and causing salting of the low-salinity water off West Luzon Island. The situation is reversed during the summer of the decaying year of a La Niña.

  13. The corrosive well waters of Egypt's western desert

    Science.gov (United States)

    Clarke, Frank Eldridge

    1979-01-01

    The discovery that ground waters of Egypt's Western Desert are highly corrosive is lost in antiquity. Inhabitants of the oases have been aware of the troublesome property for many decades and early investigators mention it in their reports concerning the area. Introduction of modern well-drilling techniques and replacements of native wood casing with steel during the 20th century increased corrosion problems and, in what is called the New Valley Project, led to an intense search for causes and corrective treatments. This revealed that extreme corrosiveness results from combined effects of relatively acidic waters with significant concentrations of destructive sulfide ion; unfavorable ratios of sulfate and chloride to less aggressive ions; mineral equilibria and electrode potential which hinder formation of protective films; relative high chemical reaction rates because of abnormal temperatures, and high surface velocities related to well design. There is general agreement among investigators that conventional corrosion control methods such as coating metal surfaces, chemical treatment of the water, and electrolytic protection with impressed current and sacrificial electrodes are ineffective or impracticable for wells in the Western Desert's New Valley. Thus, control must be sought through the use of materials more resistant to corrosion than plain carbon steel wherever well screens and casings are necessary. Of the alternatives considered, stainless steel appears to. be the most promising where high strength and long-term services are required and the alloy's relatively high cost is acceptable. Epoxy resin-bonded fiberglass and wood appear to be practicable, relatively inexpensive alternatives for installations which do. not exceed their strength limitations. Other materials such as high strength aluminum and Monel Metal have shown sufficient promise to. merit their consideration in particular locations and uses. The limited experience with pumping in these desert

  14. Root water uptake under water and salinity stresses

    Science.gov (United States)

    Moradi, A. B.; Bauser, H.; Ngo, A.; Kamai, T.; Walker, R.; Hopmans, J. W.

    2013-12-01

    Root uptake of water and nutrients is influenced by root-zone complex and dynamic processes such as soil water status, irrigation, evaporation, and leaching. Plant roots are living and functioning in a dynamic environment that is subjected to extreme changes over relatively short time and small distances. In order to better manage our agricultural resources and cope with increasing constraints of water limitation, environmental concerns and climate change, it is vital to understand plants responses to these changes in their environment. We grew chick pea (Cicer arietinum) plants, in boxes of 30 x 25 x 1 cm dimensions filled with fine sand. Layers of coarse sand (1.5 cm thick) were embedded in the fine-sand media to divide the root growth environment into sections that were hydraulically disconnected from each other. This way, each section could be independently treated with differential levels of water and salinity. The root growth and distribution in the soil was monitored on daily bases using neutron radiography. Daily water uptake was measured by weighing the containers. Changes of soil water content in each section of the containers were calculated from the neutron radiographs. Plants that part of their root system was stressed with drought or salinity showed no change in their daily water uptake rate. The roots in the stressed sections stayed turgid during the stress period and looked healthy in the neutron images. However the uptake rate was severely affected when the soil in the non-stressed section started to dry. The plants were then fully irrigated with water and the water uptake rate recovered to its initial rate shortly after irrigation. The neutron radiographs clearly illustrated the shrinkage and recovery of the roots under stress and the subsequent relief. This cycle was repeated a few times and the same trend could be reproduced. Our results show that plants' response to water- or salinity-stress ranges from full compensation to severe reduction in

  15. Spatial distribution of saline water and possible sources of intrusion ...

    African Journals Online (AJOL)

    user

    The spatial distribution of saline water and possible sources of intrusion into Lekki lagoon and transitional effects on the lacustrine ichthyofaunal characteristics were studied during March, 2006 and. February, 2008. The water quality analysis indicated that, salinity has drastically increased recently in the lagoon (0.007 to ...

  16. Spatial distribution of saline water and possible sources of intrusion ...

    African Journals Online (AJOL)

    The spatial distribution of saline water and possible sources of intrusion into Lekki lagoon and transitional effects on the lacustrine ichthyofaunal characteristics were studied during March, 2006 and February, 2008. The water quality analysis indicated that, salinity has drastically increased recently in the lagoon (0.007 to ...

  17. Water quality monitoring for high-priority water bodies in the Sonoran Desert network

    Science.gov (United States)

    Terry W. Sprouse; Robert M. Emanuel; Sara A. Strorrer

    2005-01-01

    This paper describes a network monitoring program for “high priority” water bodies in the Sonoran Desert Network of the National Park Service. Protocols were developed for monitoring selected waters for ten of the eleven parks in the Network. Park and network staff assisted in identifying potential locations of testing sites, local priorities, and how water quality...

  18. Irregular fog as a water source for desert dune beetles.

    Science.gov (United States)

    Seely, M K

    1979-09-01

    Three methods of fog-water uptake have been observed in three tribes of Namib desert dune tenebrionid beetles, Adesmiini, Eurychorini and Zophosini. The methods used correlate with distribution and gross morphology of each species but cut across phylogenetic affinities. Of the three methods described, none involve obvious fine anatomical or physical adaptations of the beetles for fog-water uptake. Rather, the beetles have evolved specific behavioural patterns for drinking water condensed on vegetation, their own dorsum or sand.Use of fog-water necessitates surface activity at times when surface temperatures and wind velocities are not optimal for these diurnal or crepuscular species. Behavioural adaptation has enabled these beetles to use irregular and unpredictable fogs as a moisture source.

  19. Influence of salinity and water content on soil microorganisms

    Directory of Open Access Journals (Sweden)

    Nan Yan

    2015-12-01

    Full Text Available Salinization is one of the most serious land degradation problems facing world. Salinity results in poor plant growth and low soil microbial activity due to osmotic stress and toxic ions. Soil microorganisms play a pivotal role in soils through mineralization of organic matter into plant available nutrients. Therefore it is important to maintain high microbial activity in soils. Salinity tolerant soil microbes counteract osmotic stress by synthesizing osmolytes which allows them to maintain their cell turgor and metabolism. Osmotic potential is a function of the salt concentration in the soil solution and therefore affected by both salinity (measured as electrical conductivity at a certain water content and soil water content. Soil salinity and water content vary in time and space. Understanding the effect of changes in salinity and water content on soil microorganisms is important for crop production, sustainable land use and rehabilitation of saline soils. In this review, the effects of soil salinity and water content on microbes are discussed to guide future research into management of saline soils.

  20. Ground-water hydrology of the Sevier Desert, Utah

    Science.gov (United States)

    Mower, R.W.; Feltis, R.D.

    1968-01-01

    The Sevier Desert, as used in this report, comprises the main part of the Sevier Desert, the Tintic Valley, and the southeastern part of the Old River Bed. It covers an area of about 3,000 square miles and occupies a large basin in the eastern part of the Basin and Range physiographic province.Large alluvial fans extend from the mountain fronts into the basin where they interfinger with eolian and lacustrine deposits and with fluvial deposits of the Sevier River. These unconsolidated deposits form a multiaquifer artesian system that is more than 1,000 feet thick and that extends from near the area of main recharge along the east side of the basin to Sevier Lake.Most of the recharge to the ground-water reservoir results from water entering alluvial fans as percolation from streams, irrigation ditches, and irrigated fields. Another important source may be water in the limestone, quartzite, and other consolidated rocks in the mountains that border the basin. Leakage from the Central Utah Canal is a major source of recharge to the water-table aquifer.Flowing wells are common in the central lowland part of the Sevier Desert, but as a result of below-normal precipitation and an increase in withdrawals from wells during 1950-64, the area of flowing wells has decreased. The quantity of ground water being wasted from flowing wells is not more than a few hundred acre-feet a year.The amount of water discharged by withdrawal from wells has increased nearly 15 times since 1950 (from 2,000 acre-feet in 1950 to 30,000 acre-feet in 1964). As a result of this increasing withdrawal, the water levels in observation wells have declined 4 feet in areas of small withdrawals to more than 7 feet near centers of pumping for public supplies and irrigation.An estimated 135,000-175,000 acre-feet of ground water is consumed by evapotranspiration each year in the 440,000 acres of desert that mainly support phreatophytes. This rate of discharge has changed little since 1950. The consumptive

  1. Aerial biomass and elemental changes in Atriplex canescens and A. acanthocarpa as affected by salinity and soil water availability

    Science.gov (United States)

    Ricardo Mata-Gonzalez; Ruben Melendez-Gonzalez; J. Jesus Martinez-Hernandez

    2001-01-01

    Atriplex canescens and A. acanthocarpa from the Chihuahuan Desert in Mexico were subjected to different salinity and irrigation treatments in a greenhouse study. Plants were grown in pots containing soil and irrigated with NaCl solutions of 0, 50, and 100 mM at 40 and 80 percent available soil water. Aerial biomass of A. canescens declined as NaCl treatments increased...

  2. Coagulation processes of kaolinite and montmorillonite in calm, saline water

    Science.gov (United States)

    Zhang, Jin-Feng; Zhang, Qing-He; Maa, Jerome P.-Y.

    2018-03-01

    A three dimensional numerical model for simulating the coagulation processes of colloids has been performed by monitoring the time evolution of particle number concentration, the size distribution of aggregates, the averaged settling velocity, the collision frequency, and the collision efficiency in quiescent water with selected salinities. This model directly simulates all interaction forces between particles based on the lattice Boltzmann method (LBM) and the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, and thus, can reveal the collision and coagulation processes of colloidal suspensions. Although using perfect spherical particles in the modeling, the results were compared with those for kaolinite and montmorillonite suspensions to demonstrate the capability of simulating the responses of these particles with highly irregular shape. The averaged settling velocity of kaolinite aggregates in quiescent saline water reached a maximum of 0.16 mm/s when the salinity increasing to about 3, and then, exhibited little dependence on salinity thereafter. Model simulations results (by choosing specific values that represent kaolinite's characteristics) indicate a similar trend: rapid decrease of the particle number concentration (i.e., rapidly flocculated, and thus, settling velocity also increases rapidly) when salinity increases from 0 to 2, and then, only increased slightly when salinity was further increased from 5 to 20. The collision frequency for kaolinite only decreases slightly with increasing salinity because that the fluid density and viscosity increase slightly in sea water. It suggests that the collision efficiency for kaolinite rises rapidly at low salinities and levels off at high salinity. For montmorillonite, the settling velocity of aggregates in quiescent saline water continuedly increases to 0.022 mm/s over the whole salinity range 0-20, and the collision efficiency for montmorillonite rises with increasing salinities.

  3. Plant-Microbe Interactions and Water Management in Arid and Saline Soils

    KAUST Repository

    Daffonchio, Daniele

    2014-12-05

    Drought and salinity are major factors limiting agriculture in many regions in the world, and their importance is predicted to even increase in the near future in parallel with the ongoing global warming and climate changes. Soil and rhizosphere microbes are potential resources for counteracting such abiotic stresses in plants. The knowledge on the roles of root microorganisms in retaining soil humidity and promoting plant growth under such abiotic stresses is analyzed in this chapter. The importance of microbial diversity in the rhizosphere for alleviating drought and salinity effects on the plant physiology is discussed in the light of “Desert Farming”, the general crop management practice that is frequently used in arid regions. The plant growth promoting functional services exerted by microorganisms within the rhizosphere in arid soils are presented in relation to the plant response under water stress.

  4. Drinking water salinity associated health crisis in coastal Bangladesh

    Directory of Open Access Journals (Sweden)

    Mahin Al Nahian

    2018-01-01

    Full Text Available Salinity intrusion in coastal Bangladesh has serious population health implications, which are yet to be clearly understood. The study was undertaken through the ‘Assessing Health, Livelihoods, Ecosystem Services and Poverty Alleviation in Populous Deltas’ project in coastal Bangladesh. Drinking water salinity and blood pressure measurements were carried out during the household survey campaign. The study explored association among Socio-Ecological Systems (SESs, drinking water salinity and blood pressure. High blood pressure (prehypertension and hypertension was found significantly associated with drinking water salinity. People exposed to slightly saline (1000–2000 mg/l and moderately saline (≥2000 mg/l concentration drinking water had respectively 17% (p < 0.1 and 42% (p < 0.05 higher chance of being hypertensive than those who consumed fresh water (<1000 mg/l. Women had 31% higher chance of being hypertensive than men. Also, respondents of 35 years and above were about 2.4 times more likely to be hypertensive compared to below 35 years age group. For the 35 years and above age group, both prehypertension and hypertension were found higher than national rural statistics (50.1% for saline water categories (53.8% for slightly and 62.5% for moderate saline. For moderate salinity exposure, hypertension prevalence was found respectively 21%, 60% and 48% higher than national statistics (23.6% in consecutive survey rounds among the respondents. Though there was small seasonal variation in drinking water salinity, however blood pressure showed an increasing trend and maximum during the dry season. Mean salinity and associated hypertension prevalence were found higher for deep aquifer (21.6% compared to shallow aquifer (20.8%. Localized increase in soil and groundwater salinity was predicted over the study area. Shallow aquifer salinity increase was projected based on modelled output of soil salinity. Rather than uniform increase, there were

  5. Tolerance of melon cultivars to irrigation water salinity

    OpenAIRE

    Pereira, Francisco A. de L.; Medeiros, José F. de; Gheyi, Hans R.; Dias, Nildo da S.; Preston, Welka; Vasconcelos, Cybelle B. e L.

    2017-01-01

    ABSTRACT The use of saline water for irrigation causes severe restriction to nutritional balance, growth and production in many crops due to the effect of salts on plant and soil. The objective of this study was to investigate the response of melon (Cucumis melo L.) cultivars to various levels of irrigation water salinity on yield and fruit quality. A field experiment was conducted in a split-plot randomized block design with four replicates. The factors were five levels of irrigation water s...

  6. Salinity guidelines for irrigation: Case studies from Water Research ...

    African Journals Online (AJOL)

    Salinity guidelines for irrigation: Case studies from Water Research Commission projects along the Lower Vaal, Riet, Berg and Breede Rivers. ... It is suggested that a more dynamic approach be used for managing salinity under irrigation at farm level, i.e. the use of models. Amongst others, future research should focus on ...

  7. Radium contamination in the Nizzana-1 water well, Negev Desert, Israel

    International Nuclear Information System (INIS)

    Minster, T.; Ilani, S.; Kronfeld, J.; Even, O.; Godfrey-Smith, D.I.

    2004-01-01

    In a search for fresh groundwater reserves in the northwestern Negev Desert of Israel, the Nizzana-1 water well drilled into the Judea Group aquifer encountered water that exhibits an anomalously high 226 Ra activity of 2.4 Bq/l, along with 133 Bq/l 222 Rn. The exploited well water is a mixture of the original Judea Group aquifer water and the underlying more saline artesian water of the Kurnub Group (or Nubian Sandstone) aquifer that is currently intruding via faults. Both aquifers elsewhere contain intrinsically low radioactivity. A study of the sedimentary sequence transected by the borehole revealed that much of the bituminous sequence of the Mount Scopus Group of Upper Cretaceous age is substantially depleted in 226 Ra. During its ascent, the Nubian Sandstone water flushes the moderately uranium enriched bituminous sediments, selectively leaching radium and/or receiving alpha-recoil additions of radium. These bituminous chalks and marls are regionally widespread. It is thus suggested that radium should be monitored where faulting allows for inter-aquiferial connections across uranium enriched bituminous sections

  8. Salinity and temperature variations around Peninsula Malaysia coastal waters

    International Nuclear Information System (INIS)

    Abdul Kadir Ishak; Jeremy Andy Anak Dominic; Nazrul Hizam Yusof; Mohd Rafaei Murtadza

    2004-01-01

    Vertical profiles of salinity and temperature were measured at several offshore stations along east and west coast of Peninsula Malaysia coastal waters. The measurements which covered South China Sea and Straits of Malacca were made during sampling cruises for Marine Database Project for Peninsula Malaysia, and during an IAEA regional training course for Marine Pollution Project. The results show that the water temperature is highest at the surface and minimum at bottom, while the salinity is lowest at the surface and highest at the bottom. In Malacca Straits, the highest surface water temperature was 30.6 degree C and the lowest bottom water temperature was 20.4 degree C, recorded at a station located in Andaman Sea. The same station also recorded the highest surface and bottom salinity i.e. 31.3 ppt and 34.4 ppt, respectively. For South China Sea, the maximum surface water temperature was 30.4 degree C and the minimum bottom temperature was 25.9 degree C, while the highest surface salinity was 33.2 ppt and the highest bottom salinity was 34.1 ppt. The water in South China Sea also showed some degrees of stratifications with thermocline zones located between 10-40 m water depths. In Malacca Straits, stronger thermocline develops at higher latitude, while at lower latitude the water is more readily mixed. Beside the spatial variations, the seawater temperature and salinity around Peninsula Malaysia also subjected to temporal variation as seawater. (Author)

  9. Effect of water regime and salinity on artichoke yield

    Directory of Open Access Journals (Sweden)

    Francesca Boari

    2012-03-01

    Full Text Available This work focuses on the effects of different salinity and water inputs on the yield of artichoke Violetto di Provenza. Two years of experimental works had been carried out in a site in Southern Italy characterized by semi-arid climate and deep loam soil. Three salinity levels of irrigation water (S0, S1 and S2 with electrical conductivity (ECw of 0.5, 5 and 10 dS m-1, respectively, were combined with three water regimes (W1, W2 and W3 corresponding in that order to 20 40 and 60% of available water depletion. The overall results of the salinity tolerance are in agreement with those from the literature. However, an higher tolerance to salinity was demonstrated when crop was watered more frequently (at 20% of available water depletion and a lower one when crop watering was performed less frequently (at 60% of available water depletion. The increase of salinity level reduced marketable yield (from 12.9 to 8.8 Mg ha-1, total heads (from 125,100 to 94,700 n ha-1 and heads mean weight (from 99.9 to 94.6 g, while increased heads dry matter (from 161.8 to 193.6 g kg-1 f.w. and reduced edible parte percentage of heads (from 35.2 to 33.2 %. Watering regimes, as average of the salinity levels, affected total heads marketable yield (115,350 n ha-1 and 11.4 Mg ha-1 for W1 and W2, 105,900 n ha-1 and 10 Mg ha-1 for W3. In addition, different watering regimes affected the secondary heads yield for which it was reduced by 3% of mean weight. The effect of different watering regimes changed with various salinity levels. In condition of moderate salinity (S1, maximum water depletion fraction to preserve heads number and weight yield was 40 and 20% of total soil available water, respectively. However, with high salinity (S2, maximum water depletion fraction to keep unchanged heads number and weight yield was 20% for both. The level of soil salinity at beginning of the crop cycle favoured the incidence of head atrophy in the main heads produced in the second year.

  10. Utilization of saline water and land: Reclaiming lost resources

    International Nuclear Information System (INIS)

    Naqvi, Mujtaba

    2001-01-01

    There is an abundance of saline water on the globe. Large tracts of land are arid and/or salt-affected, and a large number of plant species are known to be salt-tolerant. It would seem obvious that salt tolerant plants (halophytes) have a role in utilizing the two wasted resources, saline water and wastelands. We will briefly describe how these resources can be fruitfully utilized and how the IAEA has helped several countries to demonstrate the possibility of cultivating salt tolerant plant species on arid saline wastelands for economic and environmental benefit. After some brief introductory remarks we will discuss the results of the project

  11. Simulation of Salinity Distribution in Soil Under Drip Irrigation Tape with Saline Water Using SWAP Model

    Directory of Open Access Journals (Sweden)

    M. Tabei

    2016-02-01

    Full Text Available Introduction: The to be limited available water amount from one side and to be increased needs of world population from the other side have caused increase of cultivation for products. For this reason, employing new irrigation ways and using new water resources like using the uncommon water (salty water, water drainage are two main strategies for regulating water shortage conditions. On the other side, accumulation of salts on the soil surface in dry regions having low rainfall and much evaporation, i.e. an avoidable case. As doing experiment for determining moisture distribution form demands needs a lot of time and conducting desert experiments are costly, stimulator models are suitable alternatives in answering the problem concerning moving and saltiness distribution. Materials and Methods: In this research, simulation of soil saltiness under drip irrigation was done by the SWAP model and potency of the above model was done in comparison with evaluated relevant results. SWAP model was performed based on measured data in a corn field equipped with drip irrigation system in the farming year 1391-92 in the number one research field in the engineering faculty of water science, ShahidChamran university of Ahvaz and hydraulic parameters of soil obtained from RETC . Statistical model in the form of a random full base plan with four attendants for irrigating water saltiness including salinity S1 (Karoon River water with salinity 3 ds/m as a control treatment, S2 (S1 +0/5, S3 (S1 +1 and S4 (S1 +1/5 dS/m, in 3 repetition and in 3 intervals of 10 cm emitter, 20 cm emitters on the stack, at a depth of 0-90 cm (instead of each 30 cm from soil surface and intervals of 30, 60 and 90 days after modeling cultiviation was done. The cultivation way was done handheld in plots including four rows of 3 m in distance of 75 cm rows and with denseness of 80 bushes in a hectar. Drip irrigation system was of type strip with space of 20 cm pores. Results and Discussion

  12. Phenanthrene partitioning in sediment-surfactant-fresh/saline water systems

    International Nuclear Information System (INIS)

    Sun Hongwen; Wu Wenling; Wang Lei

    2009-01-01

    The objective of this study was to investigate the influence of salinity on the effectiveness of surfactants in the remediation of sediments contaminated with phenanthrene (PHE). This is an example of a more general application of surfactants in removing hydrophobic organic compounds (HOCs) from contaminated soil/sediment in saline environments via in-situ enhanced sorption or ex-situ soil washing. Salinity effects on surfactant micelle formation and PHE partitioning into solution surfactant micelles and sorbed surfactant were investigated. The critical micelle concentration of surfactants decreased, and PHE partition between surfactant micelles and water increased with increasing salinity. Carbon-normalized partition coefficients (K ss ) of PHE onto the sorbed cationic surfactant increased significantly with increasing salinity, which illustrates a more pronounced immobilization of PHE by cationic surfactant in a saline system. Reduction of PHE sorption by anionic surfactant was more pronounced in the saline system, indicating that the anionic surfactant has a higher soil washing effectiveness in saline systems. - The effectiveness of surfactant-enhanced remediation technology was promoted when applying it in estuarine environment with a higher salinity.

  13. Soil Microbial Responses to Increased Moisture and Organic Resources along a Salinity Gradient in a Polar Desert

    Science.gov (United States)

    Van Horn, David J.; Okie, Jordan G.; Buelow, Heather N.; Gooseff, Michael N.; Barrett, John E.

    2014-01-01

    Microbial communities in extreme environments often have low diversity and specialized physiologies suggesting a limited resistance to change. The McMurdo Dry Valleys (MDV) are a microbially dominated, extreme ecosystem currently undergoing climate change-induced disturbances, including the melting of massive buried ice, cutting through of permafrost by streams, and warming events. These processes are increasing moisture across the landscape, altering conditions for soil communities by mobilizing nutrients and salts and stimulating autotrophic carbon inputs to soils. The goal of this study was to determine the effects of resource addition (water/organic matter) on the composition and function of microbial communities in the MDV along a natural salinity gradient representing an additional gradient of stress in an already extreme environment. Soil respiration and the activity of carbon-acquiring extracellular enzymes increased significantly (P salinity sites but not the high-salinity site. The bacterial community composition was altered, with an increase in Proteobacteria and Firmicutes with water and organic matter additions at the low- and moderate-salinity sites and a near dominance of Firmicutes at the high-salinity site. Principal coordinate analyses of all samples using a phylogenetically informed distance matrix (UniFrac) demonstrated discrete clustering among sites (analysis of similarity [ANOSIM], P 0.40) and among most treatments within sites. The results from this experimental work suggest that microbial communities in this environment will undergo rapid change in response to the altered resources resulting from climate change impacts occurring in this region. PMID:24610850

  14. Effects of salinity stress on water uptake, germination and early ...

    African Journals Online (AJOL)

    Administrator

    2011-09-07

    Sep 7, 2011 ... pressure to apply low quality water for plant irrigation. (Schleiff, 2008). Use of low quality water is increasing salinity of soil. The osmotic pressure of soil solution is in- creased by increasing salt concentration. Increase of soil osmotic pressure causes difficulties in the water uptake of plants (Ergene, 1987; ...

  15. Saline water intrusion toward groundwater: Issues and its control

    Directory of Open Access Journals (Sweden)

    Purnama S

    2012-10-01

    Full Text Available Nowadays, saline water pollution has been gaining its importance as the major issue around the world, especially in the urban coastal area. Saline water pollution has major impact on human life and livelihood. It ́s mainly a result from static fossil water and the dynamics of sea water intrusion. The problem of saline water pollution caused by seawater intrusion has been increasing since the beginning of urban population. The problem of sea water intrusion in the urban coastal area must be anticipated as soon as possible especially in the urban areas developed in coastal zones,. This review article aims to; (i analyze the distribution of saline water pollution on urban coastal area in Indonesia and (ii analyze some methods in controlling saline water pollution, especially due to seawater intrusion in urban coastal area. The strength and weakness of each method have been compared, including (a applying different pumping patterns, (b artificial recharge, (c extraction barrier, (d injection barrier and (e subsurface barrier. The best method has been selected considering its possible development in coastal areas of developing countries. The review is based considering the location of Semarang coastal area, Indonesia. The results have shown that artificial recharge and extraction barrier are the most suitable methods to be applied in the area.

  16. Linking water and carbon cycles through salinity observed from space

    Science.gov (United States)

    Xie, X.; Liu, W. T.

    2017-12-01

    The association of ocean surface salinity in global hydrological cycle and climate change has been traditionally studied through the examination of its tendency and advection as manifestation of ocean's heat and water fluxes with the atmosphere. The variability of surface heat and water fluxes are linked to top of atmosphere radiation, whose imbalance is the main cause of global warming. Besides the link of salinity to greenhouse warming through water balance, this study will focus on the effect of changing salinity on carbon dioxide flux between the ocean and the atmosphere. We have built statistical models to estimate the partial pressure of carbon dioxide (pCO2) and ocean acidification (in terms of total alkalinity and pH) using spacebased data. PCO2 is a critical parameter governing ocean as source and sink of the accumulated greenhouse gas in the atmosphere. The exchange also causes ocean acidification, which is detrimental to marine lives and ecology. Before we had sufficient spacebased salinity measurements coincident with in situ pCO2 measurement, we trained our statistical models to use satellite sea surface temperature and chlorophyll, with one model using salinity climatology and the other without. We found significant differences between the two models in regions of strong water input through river discharge and surface water flux. The pCO2 output follows the seasonal salinity advection of the Amazon outflow. The seasonal salinity advection between Bay of Bengal and Arabian Sea are followed by change of pCO2 and total alkalinity. At shorter time scales, the signatures of rain associated with intraseasonal organized convection of summer monsoon can be detected. We have observed distribution agreement of among pCO2, surface salinity, and surface water flux for variation from a few days to a few years under the Pacific ITCZ; the agreement varies slightly with season and longitudes and the reason is under study.

  17. Water use, productivity and interactions among desert plants

    Energy Technology Data Exchange (ETDEWEB)

    Ehleringer, J.R.

    1992-11-17

    Water plays a central role affecting all aspects of the dynamics in aridland ecosystems. Productivity, stability, and competitive interactions among ecosystem components within aridlands are key processes related directly to water in deserts. The ecological studies in this project revolve around one fundamental premise: that integrated aspects of plant metabolism provide insight into the structure and function of plant communities and ecosystems. While it is difficult to extrapolate from instantaneous physiological observations to higher scales, such as whole plant performance or to interactions between plants as components of ecosystems, several key aspects of plant metabolism are scalable. Analyses of stable isotopic composition in plant tissues at natural abundance levels provide a useful tool that can provide insight into the consequences of physiological processes over temporal and spatial scales. Some plant processes continuously fractionate among light and heavy stable isotopic forms of an element; over time this results in integrated measures of plant metabolism. For example, carbon isotope fractionation during photosynthesis results in leaf carbon isotopic composition that is a measure of the set-point for photosynthetic metabolism and of water-use efficiency. Thus it provides information on the temporal scaling of a key physiological process. In contrast, hydrogen is not fractionated during water uptake through the root. Soil water availability in shallow, deep, and/or groundwater layers vary spatially; therefore hydrogen isotope ratios of xylem sap provide a direct measure of the water source currently used by a plant. The longer-term record of carbon and hydrogen isotope ratios is recorded annually in xylem tissues (tree rings). The research in this project addresses variation in stable isotopic composition of aridland plants and its consequences for plant performance and community-level interactions.

  18. Chemical fingerprinting of saline water intrusion into sewage lines.

    Science.gov (United States)

    Osman, Ola; Aina, Oluwajinmi Daniel; Ahmad, Farrukh

    2017-10-01

    High salinity in sewage sludge can affect not only the operation of wastewater treatment plants (WWTPs) but also the quality of treated water generated, thereby limiting its downstream reuse. Using data on geochemical parameters, both for the central WWTP in Abu Dhabi, UAE, and literature values for potential regional saline water sources (e.g., shallow groundwater and regional Arabian Gulf seawater), a variety of chemical fingerprinting diagnostic ratios were calculated and plotted in order to determine the source of salinity in the municipal sewage. Data were compared with data from a regional WWTP that was not impacted by salinity. Monitoring data demonstrated persistently elevated levels of salinity in the municipal wastewater arriving at the central WWTP from the city. Dilution/concentration analysis using a conductivity vs. chloride plot showed both potential sources, i.e. Arabian Gulf seawater and coastal hypersaline groundwater, as feasible sources of wastewater salinization. Further diagnostic analysis using a Panno Plot indicated that coastal groundwater was the only likely source of salinization of municipal sewage. Additional confirmation of the identity of the source and the extent of mixing using different lines of evidence like stable isotope ratios is recommended for future study.

  19. Remote Sensing of Salinity: The Dielectric Constant of Sea Water

    Science.gov (United States)

    LeVine, David M.; Lang, R.; Utku, C.; Tarkocin, Y.

    2011-01-01

    Global monitoring of sea surface salinity from space requires an accurate model for the dielectric constant of sea water as a function of salinity and temperature to characterize the emissivity of the surface. Measurements are being made at 1.413 GHz, the center frequency of the Aquarius radiometers, using a resonant cavity and the perturbation method. The cavity is operated in a transmission mode and immersed in a liquid bath to control temperature. Multiple measurements are made at each temperature and salinity. Error budgets indicate a relative accuracy for both real and imaginary parts of the dielectric constant of about 1%.

  20. Salinity controls on plant transpiration and soil water balance

    Science.gov (United States)

    Perri, S.; Molini, A.; Suweis, S. S.; Viola, F.; Entekhabi, D.

    2017-12-01

    Soil salinization and aridification represent a major threat for the food security and sustainable development of drylands. The two problems are deeply connected, and their interplay is expected to be further enhanced by climate change and projected population growth. Salt-affected land is currently estimated to cover around 1.1 Gha, and is particularly widespread in semi-arid to hyper-arid climates. Over 900 Mha of these saline/sodic soils are potentially available for crop or biomass production. Salt-tolerant plants have been recently proposed as valid solution to exploit or even remediate salinized soils. However the effects of salinity on evapotranspiration, soil water balance and the long-term salt mass balance in the soil, are still largely unexplored. In this contribution we analyze the feedback of evapotranspiration on soil salinization, with particular emphasis on the role of vegetation and plant salt-tolerance. The goal is to introduce a simple modeling framework able to shed some light on how (a) soil salinity controls plant transpiration, and (b) salinization itself is favored/impeded by different vegetation feedback. We introduce at this goal a spatially lumped stochastic model of soil moisture and salt mass dynamics averaged over the active soil depth, and accounting for the effect of salinity on evapotranspiration. Here, the limiting effect of salinity on ET is modeled through a simple plant response function depending on both salt concentration in the soil and plant salt-tolerance. The coupled soil moisture and salt mass balance is hence used to obtain the conditional steady-state probability density function (pdf) of soil moisture for given salt tolerance and salinization level, Our results show that salinity imposes a limit in the soil water balance and this limit depends on plant salt-tolerance mainly through the control of the leaching occurrence (tolerant plants exploit water more efficiently than the sensitive ones). We also analyzed the

  1. Thermodynamics of saline and fresh water mixing in estuaries

    Science.gov (United States)

    Zhang, Zhilin; Savenije, Hubert H. G.

    2018-03-01

    The mixing of saline and fresh water is a process of energy dissipation. The freshwater flow that enters an estuary from the river contains potential energy with respect to the saline ocean water. This potential energy is able to perform work. Looking from the ocean to the river, there is a gradual transition from saline to fresh water and an associated rise in the water level in accordance with the increase in potential energy. Alluvial estuaries are systems that are free to adjust dissipation processes to the energy sources that drive them, primarily the kinetic energy of the tide and the potential energy of the river flow and to a minor extent the energy in wind and waves. Mixing is the process that dissipates the potential energy of the fresh water. The maximum power (MP) concept assumes that this dissipation takes place at maximum power, whereby the different mixing mechanisms of the estuary jointly perform the work. In this paper, the power is maximized with respect to the dispersion coefficient that reflects the combined mixing processes. The resulting equation is an additional differential equation that can be solved in combination with the advection-dispersion equation, requiring only two boundary conditions for the salinity and the dispersion. The new equation has been confronted with 52 salinity distributions observed in 23 estuaries in different parts of the world and performs very well.

  2. Elementary introduction into thermal desalination of saline waters

    International Nuclear Information System (INIS)

    Froehner, K.R.

    1979-01-01

    The principle of thermal conversion of saline waters into potable water are described from an elementary point of view in an easy understandable manner, covering distillation, submerged coil evaporation, flash evaporation, multiple effect distillation, vapour compression, and solar distillation in simple solar stills. (orig.)

  3. Effect of Two Halophyte Plants Irrigated with Saline Water on Soil Salinization under Different Soil Type

    International Nuclear Information System (INIS)

    Abdel-Sabour, M. F.; Rizk, M. A.; Abdel Aziz, A.; Moustafa, S. M.; Eigala, A. M.; Abuo El-Naga, H.

    2007-01-01

    A lysimeter experiment was conducted to evaluate the impact of saline water irrigation at three levels namely, fresh water (0.3), 4 and 8 dS/m on salt accumulation and its effect on different soil types. The tested halophyte plants were Kallar grass and Atriplex (Salt bush). The tested soil types were sandy, calcareous and clayey soils. Irrigating the soil with saline water (either 4 or 8 dS/m) resulted in increasing salinity levels in soil profile with different orders of magnitude, depending on the soil type layer and the cultivated plant. Kallar grass seems limit the accumulation of salts in soil profile, compared to Atriplex at any tested soil. This may be attributed to its root effect on soil profile such as dispersed soil matrix and improved soil structure, which provide channels for solute movement through the profile under halophyte cultivation. Calculating the SAR average values for each irrigation treatment (18 values) showed significant increase in soil SAR values, especially under Kallar grass compared to Atriplex. The highest SAR values were observed in the case of clayey soil. However, the relevant SAR values under Atriplex cultivation were always lower. Values for SAR were always higher in the saline clayey > calcareous > sandy soils

  4. Influence of salinity and water regime on tomato for processing

    Directory of Open Access Journals (Sweden)

    Vito Cantore

    2012-03-01

    Full Text Available The effects of salinity and watering regime on tomato crop are reported. The trials have been carried out over two years in Southern Italy on a deep loam soil. Three saline levels of irrigation water (with electrical conductivity of 0.5, 5 and 10 dS m-1, three watering regimes (at 20, 40 and 60% of available water depletion, and two cultivars (HLY19 and Perfectpeel were compared. The overall results related to the salinity tolerance are in agreement with those from the literature indicating that water salinity reduced marketable yield by 55% in respect to the control treatments. The irrigation regimes that provided higher total and marketable yield were at 40 and 60% of available water depletion (on average, 90.5 and 58.1 Mg ha-1 against 85.3 and 55.5 Mg ha-1 of the 20% available water depletion. Saline and irrigation treatments did not affect sunburned fruits, while affected incidence of fruits with blossom-end rot. The former disease appeared more dramatically in saline treatments (+28% in respect to the control, and occurred mainly in HLY19. The disease incidence was by 52% lower in W2 respect to the W1 and W3. Fruit firmness was higher in S0, whereas it was not affected by irrigation regimes. Total soluble solids and dry matter content of tomato fruits were increased by salinity, whereas it was not affected by irrigation regimes and cultivars. The pH and the titratable acidity remained unchanged between the years, the cultivar and the saline and irrigation treatments. Similarly to the last parameters, the fruit ascorbic acid content remained unchanged in relation to the treatments, but it was higher in HLY19. The recommended thresholds of easily available water to preserve total and marketable yield were at 40 and 60%, respectively. Watering more frequently, instead, on the soil type of the trial, probably caused water-logging and root hypoxia affecting negatively yield.

  5. A model for the development of marginal water sources in arid zones: The case of the Negev Desert, Israel

    Science.gov (United States)

    Brimberg, Jack; Oron, Gideon; Mehrez, Abraham

    1993-09-01

    A management model is presented for the optimal development of marginal water sources in arid zones in conjunction with minimizing the dependence on high-quality water. These marginal sources, which may include among others saline groundwater, treated wastewater, and runoff water, are required to augment a limited supply from regional sources. The objective is to minimize operational and capital costs while simultaneously allocating a conventional regional supply in a best way among a set of local sites. A novel aspect is the consideration of water quality as an additional constraint in the decision model. In this way an optimal investment strategy for marginal water source development and use is obtained while satisfying quality requirements at the individual sites. The model formulated takes the form of a mixed binary integer linear problem. The main purpose of the presented model is to delineate a methodology for marginal water considerations and development in arid zones. Water qualities, supply and demand for diverse uses, and related costs are of primary importance. Several simplifying assumptions are made, such as aggregation on an annual basis, in order to cope with the essential features of the problem at a reasonable level of complexity. These assumptions may be relaxed at a later, more detailed stage of analysis. A case study of the Negev Desert in southern Israel is shown. An important conclusion is that saline groundwater production at local demand sites should be increased dramatically. The usefulness of sensitivity analysis in the decision process is also demonstrated.

  6. Wheat Response to a Soil Previously Irrigated with Saline Water

    Directory of Open Access Journals (Sweden)

    Vito Sardo

    2011-02-01

    Full Text Available A research was conducted aimed at assessing the response of rainfed, lysimeter-grown wheat to various levels of soil salinity, in terms of dry mass production, inorganic and organic components, sucrose phosphate synthase (SPS and sucrose synthase (SS activity. One additional scope was the assessment of soil ability to recover from applied salts by means of winter precipitations. The results confirmed the relatively high salt tolerance of wheat, as demonstrated by the mechanisms enacted by plants to contrast salinity at root and leaf level. Some insight was gained in the relationships between salinity and the various inorganic and organic components, as well as with SPS and SS activity. It was demonstrated that in a year with precipitations well below the average values (305 mm vs 500 the leaching action of rain was sufficient to eliminate salts accumulated during summer irrigation with saline water.

  7. Data measured on water collected from eastern Mojave Desert, California

    Energy Technology Data Exchange (ETDEWEB)

    Rose, Tim P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-08-17

    In March of 2000 field collection of water from the Eastern Mojave Desert resulted in the measurement of stable isotope, radiocarbon, tritium, and limited dissolved noble gases. This work was follow-on to previous studies on similar systems in southern Nevada associated with the Nevada Test Site (Davisson et al., 1999; Rose and Davisson, 2003). The data for groundwater from wells and springs was never formally published and is therefore tabulated in Table 1 in order to be recorded in public record. In addition 4 years of remote precipitation data was collected for stable isotopes and is included in Table 2. These studies, along with many parallel and subsequent ones using isotopes and elemental concentrations, are all related to the general research area of tracing sources and quantifying transport times of natural and man-made materials in the environment. This type of research has direct relevance in characterizing environmental contamination, understanding resource development and protection, designing early detection in WMD related terrorism, and application in forensics analysis.

  8. Environmental Evaluation of Soil Salinity with Various Watering Technologies Assessment.

    Science.gov (United States)

    Seitkaziev, Adeubay; Shilibek, Kenzhegali; Fakhrudenova, Idiya; Salybayev, Satybaldy; Zhaparova, Sayagul; Duisenbayeva, Saule; Bayazitova, Zulfia; Aliya, Maimakova; Seitkazieva, Karlygash; Aubakirov, Hamit

    2018-01-01

      The purpose of this study is to develop mathematical tools for evaluating the level of environmental safety of various watering technologies. A set of indicators, was developed with regard to the natural factors, the nature of the man-induced load, degradation type, and characteristics of the disruption of humification conditions. Thermal and physical characteristics of the soil, the state of its surface, and meteorological factors, including air temperature, relative humidity, precipitation, wind speed, solar radiation, etc. were studied with a view to determining the heat and air exchange in the soil. An environmental evaluation of the methods for saline land development was conducted with regard to the heat and moisture supply. This tool can be used to determine the level of environmental safety of soil salinization during the environmental evaluation of the investigation of soil salinity with various watering technologies.

  9. Assessing water stress of desert vegetation using remote sensing : the case of the Tamarugo forest in the Atacama Desert (Northern Chile)

    NARCIS (Netherlands)

    Chávez Oyanadel, R.O.

    2014-01-01

    Water stress assessment of natural vegetation plays a key role in water management of desert ecosystems. It allows scientists and managers to relate water extraction rates to changes in vegetation water condition, and consequently to define safe water extraction rates for maintaining a healthy

  10. Impacts of irrigation regimes with saline water on carrot productivity and soil salinity

    Directory of Open Access Journals (Sweden)

    Kamel Nagaz

    2012-01-01

    Full Text Available A three-year study was conducted to evaluate the effects of different irrigation regimes with saline water on soil salinity, yield and water productivity of carrot as a fall-winter crop under actual commercial-farming conditions in the arid region of Tunisia. Carrot was grown on a sandy soil and surface-irrigated with a water having an ECi of 3.6 dS/m. For the three years, a complete randomized block design with four replicates was used to evaluate five irrigation regimes. Four irrigation methods were based on the use of soil water balance (SWB to estimate irrigation amounts and timing while the fifth consisted of using traditional farmers practices. SWB methods consisted in replacement of cumulated ETc when readily available water is depleted with levels of 100% (FI-100, 80% (DI-80 and 60% (DI-60. FI-100 was considered as full irrigation while DI-80 and DI-60 were considered as deficit irrigation regimes. Regulated deficit irrigation regime where 40% reduction is applied only during ripening stage (FI-DI60 was also used. Farmer method (Farmer consisted in giving fixed amounts of water (25 mm every 7 days from planting till harvest. Results on carrot production and soil salinization are globally consistent between the three-year experiments and shows significant difference between irrigation regimes. Higher soil salinity in the root zone is observed at harvest under DI-60 (3.1, 3.4, 3.9 dS/m, respectively, for the three years and farmer irrigation (3.3, 3.6, 3.9 dS/m treatments compared to FI-100 treatment (2.3, 2.6 and 3.1 dS/m. Relatively low ECe values were also observed under FI-DI60 and DI-80 treatments with respectively (2.7, 3, 3.5 dS/m and (2.5, 2.9, 3.3 dS/m. ECe values under the different irrigation treatments were generally lower than or equal to the EC of irrigation water used. Rainfall received during fall and/or winter periods (57, 26 and 29 mm, respectively, during the three years contributed probably to leaching soluble

  11. Dynamic changes in water and salinity in saline-alkali soils after simulated irrigation and leaching.

    Directory of Open Access Journals (Sweden)

    Shutao Wang

    Full Text Available Soil salinization is a global problem that limits agricultural development and impacts human life. This study aimed to understand the dynamic changes in water and salinity in saline-alkali soil based on an indoor soil column simulation. We studied the changes in the water and salt contents of soils with different degrees of salinization under various irrigation conditions. The results showed that after seven irrigations, the pH, conductivity and total soluble salt content of the percolation samples after irrigation generally increased initially then decreased with repeated irrigation. The soil moisture did not change significantly after irrigation. The pH, conductivity, and total soluble salt content of each layer of the soil profile exhibited general declining trends. In the soil profile from Changguo Township (CG, the pH decreased from 8.21-8.35 to 7.71-7.88, the conductivity decreased from 0.95-1.14 ms/cm to 0.45-0.68 ms/cm, and the total soluble salt content decreased from 2.63-2.81 g/kg to 2.28-2.51 g/kg. In the soil profile from Zhongjie Industrial Park (ZJ, the pH decreased from 8.36-8.54 to 7.73-7.96, the conductivity decreased from 1.58-1.68 ms/cm to 1.45-1.54 ms/cm, and the total soluble salt decreased from 2.81-4.03 g/kg to 2.56-3.28 g/kg. The transported salt ions were primarily K+, Na+ and Cl-. After several irrigations, a representative desalination effect was achieved. The results of this study can provide technical guidance for the comprehensive management of saline-alkali soils.

  12. Salinization and arsenic contamination of surface water in southwest Bangladesh.

    Science.gov (United States)

    Ayers, John C; George, Gregory; Fry, David; Benneyworth, Laura; Wilson, Carol; Auerbach, Leslie; Roy, Kushal; Karim, Md Rezaul; Akter, Farjana; Goodbred, Steven

    2017-09-11

    To identify the causes of salinization and arsenic contamination of surface water on an embanked island (i.e., polder) in the tidal delta plain of SW Bangladesh we collected and analyzed water samples in the dry (May) and wet (October) seasons in 2012-2013. Samples were collected from rice paddies (wet season), saltwater ponds used for brine shrimp aquaculture (dry season), freshwater ponds and tidal channels (both wet and dry season), and rainwater collectors. Continuous measurements of salinity from March 2012 to February 2013 show that tidal channel water increases from ~0.15 ppt in the wet season up to ~20 ppt in the dry season. On the polder, surface water exceeds the World Health Organization drinking water guideline of 10 μg As/L in 78% of shrimp ponds and 27% of rice paddies, raising concerns that produced shrimp and rice could have unsafe levels of As. Drinking water sources also often have unsafe As levels, with 83% of tubewell and 43% of freshwater pond samples having >10 μg As/L. Water compositions and field observations are consistent with shrimp pond water being sourced from tidal channels during the dry season, rather than the locally saline groundwater from tubewells. Irrigation water for rice paddies is also obtained from the tidal channels, but during the wet season when surface waters are fresh. Salts become concentrated in irrigation water through evaporation, with average salinity increasing from 0.43 ppt in the tidal channel source to 0.91 ppt in the rice paddies. Our observations suggest that the practice of seasonally alternating rice and shrimp farming in a field has a negligible effect on rice paddy water salinity. Also, shrimp ponds do not significantly affect the salinity of adjacent surface water bodies or subjacent groundwater because impermeable shallow surface deposits of silt and clay mostly isolate surface water bodies from each other and from the shallow groundwater aquifer. Bivariate plots of conservative element

  13. Identifying the cause of toxicity of a saline mine water.

    Directory of Open Access Journals (Sweden)

    Rick A van Dam

    Full Text Available Elevated major ions (or salinity are recognised as being a key contributor to the toxicity of many mine waste waters but the complex interactions between the major ions and large inter-species variability in response to salinity, make it difficult to relate toxicity to causal factors. This study aimed to determine if the toxicity of a typical saline seepage water was solely due to its major ion constituents; and determine which major ions were the leading contributors to the toxicity. Standardised toxicity tests using two tropical freshwater species Chlorella sp. (alga and Moinodaphnia macleayi (cladoceran were used to compare the toxicity of 1 mine and synthetic seepage water; 2 key major ions (e.g. Na, Cl, SO4 and HCO3; 3 synthetic seepage water that were modified by excluding key major ions. For Chlorella sp., the toxicity of the seepage water was not solely due to its major ion concentrations because there were differences in effects caused by the mine seepage and synthetic seepage. However, for M. macleayi this hypothesis was supported because similar effects caused by mine seepage and synthetic seepage. Sulfate was identified as a major ion that could predict the toxicity of the synthetic waters, which might be expected as it was the dominant major ion in the seepage water. However, sulfate was not the primary cause of toxicity in the seepage water and electrical conductivity was a better predictor of effects. Ultimately, the results show that specific major ions do not clearly drive the toxicity of saline seepage waters and the effects are probably due to the electrical conductivity of the mine waste waters.

  14. Detection of water bodies in Saline County, Kansas

    Science.gov (United States)

    Barr, B. G. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. A total of 2,272 water bodies were mapped in Saline County, Kansas in 1972 using ERTS-1 imagery. A topographic map of 1955 shows 1,056 water bodies in the county. The major increase took place in farm ponds. Preliminary comparison of image and maps indicates that water bodies larger than ten acres in area proved consistently detectable. Most water areas between four and ten acres are also detectable, although occasionally image context prevents detection. Water areas less than four acres in extent are sometimes detected, but the number varies greatly depending on image context and the individual interpretor.

  15. SALINITY EFFECT ON SEEDLING GROWTH, WATER, SODIUM ...

    African Journals Online (AJOL)

    AISA

    AND POTASSIUM DISTRIBUTIONS IN THE MANGROVE. SPECIES (Avicennia germinans L. ... EFFET DE LA SALINITE SUR LA CROISSANCE, LA DISTRIBUTION DES TENEURS EN EAU, SODIUM ET POTASSIUM. D'UNE ESPECE DE .... distilled water and stored for germination studies. After three days, seedlings were ...

  16. Geophysical study of saline water intrusion in Lagos municipality

    African Journals Online (AJOL)

    aghomotsegin

    Saline water intrusion presently constitutes serious concerns in the Lagos municipality just like many other coastal cities, thus necessitating its intervallic study. The present study involving 52 borehole logs (consisting of natural gamma and electrical resistivity components) was aimed at delineating intruded and vulnerable ...

  17. Effects of salinity stress on water uptake, germination and early ...

    African Journals Online (AJOL)

    This research was conducted for the determination of effects of salinity stress on water uptake of seed, germination and early seedling development of perennial ryegrass (Lolium perenne L. cv. Ovation) in the seed laboratory of Field Crops, Department of Agricultural Faculty of Namik Kemal University, Tekirdag, Turkey, ...

  18. Salinity effect on seedling growth, water, sodium and potassium ...

    African Journals Online (AJOL)

    Mature leaves exhibited good adaptative behavior toward salinity stress by increasing succulence due to absorption of large quantities of water and K+ in leaves. Potassium uptake in leaves was not found to be affected by NaCl concentration. As a consequence, monovalent cations adsorption resulted in an increase in the ...

  19. Geophysical study of saline water intrusion in Lagos municipality ...

    African Journals Online (AJOL)

    Saline water intrusion presently constitutes serious concerns in the Lagos municipality just like many other coastal cities, thus necessitating its intervallic study. The present study involving 52 borehole logs (consisting of natural gamma and electrical resistivity components) was aimed at delineating intruded and vulnerable ...

  20. Ecosystem responses to warming and watering in typical and desert steppes

    OpenAIRE

    Zhenzhu Xu; Yanhui Hou; Lihua Zhang; Tao Liu; Guangsheng Zhou

    2016-01-01

    Global warming is projected to continue, leading to intense fluctuations in precipitation and heat waves and thereby affecting the productivity and the relevant biological processes of grassland ecosystems. Here, we determined the functional responses to warming and altered precipitation in both typical and desert steppes. The results showed that watering markedly increased the aboveground net primary productivity (ANPP) in a typical steppe during a drier year and in a desert steppe over two ...

  1. Use of Saline Water in Energy Development

    OpenAIRE

    Israelsen, C. Earl; Adams, V. Dean; Batty, J. Clair; George, Dennis B.

    1980-01-01

    Maps were made of the Upper Colorado River Basin showing locations of coal deposits, oil and gas, oil shale, uranium, and tar sand, in relationship to cities and towns in the area. Superimposed on these are locations of wells showing four ranges of water quality; 1,000-3,000 mg/l, 3,000-10,000 mg/l, 10,000-35,000 mg/l, and over 35,000 mg/l. Information was assembled relative to future energy-related projects in th...

  2. Geochemical water signature in the Bahariya Depression, Western Desert, Egypt

    Science.gov (United States)

    Sciarra, Alessandra; Mazzini, Adriano; Lupi, Matteo; Hammed, Mohammed S.

    2017-04-01

    The Bahariya Oasis is located about 200 km SW of Cairo in the central part of the Western Desert of Egypt. It occupies a sub-elliptic 40 km wide depression stretching NE-SW for approximately 90 km. The Bahariya Oasis has been targeted for numerous geological studies on structural geology, stratigraphy, and iron ore deposits. The oasis was characterized since the Roman times by the presence of natural hydrothermal springs venting water from the relatively shallow Nubia Sandstone formation. Inside the depression are visible numerous circular concentric features that morphologically resemble the hydrothermal vent complexes observed at igneous provinces in other localities of the planet. In order to investigate the origin and the mechanisms of formation of these features, we conducted a fieldwork survey as well as fluids sampling from the available well sites. The aim was to constrain the origin of the fluids that potentially triggered or facilitated the formation of the concentric structures observed on the field. This study presents the geochemical results of groundwaters and soil gas samples. Ten samples were collected from deep wells present in the area. In particular, 8 warm waters were collected by wells between 800 m and 1200 m deep. The measured temperatures at these sites range from 36.5 °C to 52.3°C, while the coldest wells have temperatures ranging from 27.9 °C to 36.5°C. For each sample collected from the wells we analyzed the major, minor and trace elements, dissolved gases (He, Ne, H2, O2, N2, CH4, CO2, Rn), and relative isotopic values. In the areas around the wells we measured CO2 and CH4 fluxes as well as radon activity. Overall, the water showed a high value of dissolved Rn, ranging from 9 to 43 Bq/l, and dissolved CO2 ranging from 5.9 to 17.4 cc/l. The waters show a radiogenic signature of isotopic helium, highlighting very prolonged interaction with local crust enriched in radiogenic elements. The isotopic values of δ18O and δD show a clear

  3. Water logging and salinity control for environmentally sustainable crop production

    International Nuclear Information System (INIS)

    Chaudhry, M.R.; Bhutta, M.N.

    2005-01-01

    Irrigation supplies at proper time and adequate quantities are imperative for potential agricultural production under arid and semi-arid climatic conditions. To achieve this goal one of the largest integrated irrigation network was established. Without adequate drainage it resulted in the problems of water logging and salinity. To control these problems a big programme of Salinity Control and Reclamation projects (SCARPs) was initiated during 1960 and 82 such SCARPs have been completed and 9 were in progress up to June, 2002 covering an area of 18.6 ma (7.5 mh) at a cost of Rs.93 billions. Under these projects 12746 tube wells in fresh, 3572 in saline groundwater and 13726 km surface and 12612 km tile pipes covering 6391.7 ha, 160 km interceptor drains have been constructed an area of 0.998 ma (GCA). In addition to this some other measures like on farm water management, canal command project, canal lining, construction of evaporation ponds, establishment of research Inst./Organizations were also taken. Many drainage plans like Master Plan (1963), Northern Regional Plan (1967), Water Sector Investment Plan Study (1990), Right Bank Master Plan (1992), Drainage Sector Environmental Assessment (1993) and National Drainage Programme (1995) were prepared and implemented. The cost of the, phase-I of the National Drainage Programme was 785 million US$. The main activities undertaken were remodeling/extension of existing surface and new drains; rehabilitation/replacement of saline ground water (SGW) tube wells; construction of interceptor drains, reclamation of waterlogged areas through biological drainage and transfer of fresh ground water tube wells to the farmers. The data indicate that all the measures taken have played a significant role in reducing the water logging, salinity/sodicity and have increased the crop production and consequently improved the socio-economic conditions of the peoples especially the farming community. The environment in these areas was also

  4. Chemical interaction of fresh and saline waters with compacted bentonite

    International Nuclear Information System (INIS)

    Muurinen, A.; Lehikoinen, J.; Melamed, A.; Pitkaenen, P.

    1996-01-01

    The interaction of compacted sodium bentonite with fresh and saline ground-water simulant was studied. The parameters varied in the experiments were the compositions of the solutions and oxygen and carbon dioxide content in the surroundings. The main interests of the study were the chemical changes in the experimental solution, bentonite porewater and bentonite together with the microstructural properties of bentonite. The major processes with fresh water were the diffusion of sodium, potassium, sulphate, bicarbonate and chloride from bentonite to the solution, and the diffusion of calcium and magnesium from the solution into bentonite. The major processes in the experiments with saline water were the diffusion of the sodium, magnesium, sulphate and bicarbonate from bentonite into the solution, and the diffusion of calcium from the solution into bentonite

  5. Effect of water stress on in vitro mycelium cultures of two mycorrhizal desert truffles.

    Science.gov (United States)

    Navarro-Ródenas, Alfonso; Lozano-Carrillo, M Cecilia; Pérez-Gilabert, Manuela; Morte, Asunción

    2011-05-01

    The ability of two species of desert truffle, Terfezia claveryi strain TcS2 and Picoa lefebvrei strain OL2, to tolerate water stress in pure culture has been investigated. Both T. claveryi and P. lefebvrei strains exhibited a mycelium growth pattern characteristic of drought tolerant species. However, they were only tolerant to moderate water stress, below -1.07 MPa, with the P. lefebvrei isolate being slightly more drought tolerant than the T. claveryi isolate. The increased alkaline phosphatase (ALP) activity observed in both fungi at moderate water stress with respect to the control indicated the functional adaptation of these mycelia to these drought conditions. ALP activity can be used as an indicator of the metabolic activity of these fungi. Slight water stress (-0.45 MPa) could improve mycelial inoculum production of these desert truffles. Moreover, P. lefebvrei could be a good candidate for further desert truffle mycorrhizal plant cultivation programmes in semiarid Mediterranean areas.

  6. Effect of Different Alternate Irrigation Strategies using Saline and Non-Saline Water on Corn Yield, Salinity and Moisture Distribution in Soil Profile

    Directory of Open Access Journals (Sweden)

    Ali Reza Kiani

    2017-01-01

    Full Text Available Introduction: Lack of water and deterioration in the quality of soil and water resources are considered to be the prime cause of reduced crop yield in arid and semi-arid regions ‘More crop per drop’ by trickle irrigation, deficit irrigation, and uncommon water are the best strategies for mitigating water crises. Different irrigation management strategies are needed to increase production in different areas. In areas where sufficient water is available, a full irrigation strategy could be a suitable option, while in areas where water is limited, deficit irrigation would be an appropriate method, and finally in areas where water resources are saline, management strategies for achieving sustainable production as well as economic yields would be suitable. Maize is the third most important grain crop in the world following wheat and rice and it is the main source of nutrition for humans and animals. Because of the importance of maize in the world, increasing maize production under environmental stresses is a big challenge for agricultural scientists. Different methods of irrigation and the use of saline water that had satisfactory results for increasing agricultural production have been studied by several investigators . The main objective of this study was to establish an efficient use of limited water resources as well as to explore the possibility of replacing saline water with fresh water using different management techniques. Materials and Methods: A field experiment was conducted over two maize cropping seasons (2012–2013 in northern Iran (Gorgan Agricultural Research Station to compare different alternate irrigation scenarios using saline water on corn yield, salinity and soil moisture distribution in a randomized complete block design with three replications. Treatments were: T1 and T2 = 100 and 50 % of crop water requirement with non-saline water, respectively; T3 and T4 = variable and fixed full irrigation with saline and non-saline

  7. Evaluation of Different Rice Genotypes Tolerance to Saline Irrigation Water

    Directory of Open Access Journals (Sweden)

    S. Jafari Rad

    2015-12-01

    Full Text Available To study the responses of seven rice genotypes (Khazar, SA13, Deylam, Sange Joe, Sepidrud, 831 and T5 to different levels of irrigation water salinity, and determining grain yield based on tolerance indices, a CRD based factorial pot experiment with five levels of irrigation water salinity (1, 2, 4, 6 and 8 dSm-1 and three replications was carried out at Rice Research Institute of Iran in 2011. Indices such as SSI, TOL, MP, GMP, HM, STI, YI and YSI were calculated and their correlations with grain yield were estimated for both stress and non-stress conditions. Results indicated significant differences among genotypes and the indices within both conditions. Results also showed that STI and MP indices could be considered as the best indices to screen salt tolerant genotypes. Among the genotypes used in the experiment, T5 produced the highest yield in both non-stress (19.71 g/plant and stress (10.69 g/plant conditions, while the lowest yield in normal (11.84 g/plant and stressful (4.29 g/plant conditions was recorded for Deylam and Khazar, respectively. The highest and the lowest percentage of yield reduction were found in Khazar (69.49% and Sange Joe (31.48% in stressful conditions, respectively. Overall, genotypes T5, 831, Sepidrud and Sange Joe can probably be considered as superior high yielding genotypes in both saline and non-saline conditions for further research.

  8. Precipitation of salt in saline water drop on superhydrophobic surface

    Science.gov (United States)

    Shin, Bongsu; Moon, Myoung-Woon; Kim, Ho-Young

    2012-11-01

    In the membrane distillation process, water vapor of heated, pressurized saline water is transported across the membrane to be collected as pure water. While the water-repellency of the membrane surface has been considered an important parameter affecting the distillation efficiency, the resistance of the membrane to the contamination due to salt has gathered little scientific interest thus far. Here we experimentally investigate the precipitation of salt in sessile saline water drops, to find drastic differences in salt crystallization behavior depending on the water-repellency of solid surface. On a moderately hydrophobic surface with a static contact angle with water being about 150 degrees, salt crystals are aligned and stacked along the initial contact line, forming an interesting structure resembling an igloo. On a superhydrophobic surface with about 164 degrees of static contact angle with water, salt crystallizes only at the center of the drop-solid contact area, forming a pebble-shaped structure. We explain this difference by comparing the evaporation modes (constant contact radius versus constant contact angle) of the sessile drops on those surfaces. We also visualize the liquid flow within drops undergoing evaporation and precipitation at the same time using PIV.

  9. Plant Response to Differential Soil Water Content and Salinity

    Science.gov (United States)

    Moradi, A. B.; Dara, A.; Kamai, T.; Ngo, A.; Walker, R.; Hopmans, J. W.

    2011-12-01

    Root-zone soil water content is extremely dynamic, governed by complex and coupled processes such as root uptake, irrigation, evaporation, and leaching. Root uptake of water and nutrients is influenced by these conditions and the processes involved. Plant roots are living and functioning in a dynamic environment that is subjected to extreme changes over relatively short time and small distances. In order to better manage our agricultural resources and cope with increasing constraints of water limitation, environmental concerns and climate change, it is vital to understand plants responses to these changes in their environment. We grew chick pea (Cicer arietinum) plants, in boxes of 30 x 25 x 1 cm dimensions filled with fine sand. Layers of coarse sand (1.5 cm thick) were embedded in the fine-sand media to divide the root growth environment into sections that were hydraulically disconnected from each other. This way, each section could be independently treated with differential levels of water and salinity. The root growth and distribution in the soil was monitored on daily bases using neutron radiography. Daily water uptake was measured by weighing the containers. Changes of soil water content in each section of the containers were calculated from the neutron radiographs. Plants that part of their root system was stressed with drought or salinity showed no change in their daily water uptake rate. The roots in the stressed sections stayed turgid during the stress period and looked healthy in the neutron images. However the uptake rate was severely affected when the soil in the non-stressed section started to dry. The plants were then fully irrigated with water and the water uptake rate recovered to its initial rate shortly after irrigation. The neutron radiographs clearly illustrated the shrinkage and recovery of the roots under stress and the subsequent relief. This cycle was repeated a few times and the same trend could be reproduced. Our results show that plants

  10. Measurement of flowing water salinity within or behind wellbore casing

    International Nuclear Information System (INIS)

    Arnold, D.M.

    1981-01-01

    Water flowing within or behind a wellbore casing is irradiated with 14 MeV neutrons from a source in a downhole sonde. Gamma radiation from the isotope nitrogen-16 induced from the O 16 (n,p)N 16 reaction and the products of either the Na 23 (n,α)F 20 or the Cl 37 (n,α)P 34 reactions is measured in intensity and energy with detectors in the sonde. From the gamma radiation measurements, the relative presence of oxygen to at least one of sodium or chlorine in the water is measured, and from the measurement the salinity of the water is to be determined. (author)

  11. Physiological ecology of desert iguana (Dipsosaurus dorsalis) eggs: temperature and water relations

    Energy Technology Data Exchange (ETDEWEB)

    Muth, A.

    1980-12-01

    The soil environment imposes constraints on the timing of oviposition and the location of suitable sites for egg burrows of the desert iguana (Dipsosaurus dorsalis). The effects of temperature and water potential on the developmental period and hatching success of eggs were determined. Eggs hatch normally between 28/sup 0/ and 38/sup 0/C at environmental water potentials between -50 and -1500 kPa. Predictions were derived for the timing and placement of egg clutches based on soil water potential and temperature profiles measured in the field and on the results of laboratory incubation experiments. The results suggest that egg burrows should be located at depths >22 cm in washes or possibly in sparsely vegetated areas away from creosote bushes. The biogeography of desert iguanas within the United States is discussed in relation to soil environments and tolerances of eggs. The physical factors affecting incubation may limit the geographical range of desert iguanas.

  12. Shrimp aquaculture in low salinity water feeded with worm flavor

    Directory of Open Access Journals (Sweden)

    Wenceslao Valenzuela Quiñónez

    2012-09-01

    Full Text Available Shrimp aquaculture in Sinaloa is one of the top economic enterprises, generating many jobs and earns significant incomes every year. Shrimp feed is an essential part of maintaining healthy production. In this initial approach of shrimp growth in low salinity water, were tested two formulas of animal protein composed of 40% (APL1 and 20% (APL2 worm protein, a commercial diet, and no supplementary feed. Physicochemical parameters did not have a direct influence in shrimpbehavior. After six weeks of experimentation, shrimp fed with commercial diet had a weight gain 20% higher than those feed with worm protein. There were no significantly differences between sizes with respect to 40% animal protein and 20% animal protein with the commercial diet (P  0.05. However, shrimp fed worm protein had lower mortality. The use of worm protein could be an option to maintain a high quantity of shrimp reared in low salinity waters.

  13. Shrimp aquaculture in low salinity water feeded with worm flavor

    OpenAIRE

    Wenceslao Valenzuela Quiñónez; Gerardo Rodríguez-Quiroz; Héctor Manuel Esparza Leal; Eusebio Nava Pérez

    2012-01-01

    Shrimp aquaculture in Sinaloa is one of the top economic enterprises, generating many jobs and earns significant incomes every year. Shrimp feed is an essential part of maintaining healthy production. In this initial approach of shrimp growth in low salinity water, were tested two formulas of animal protein composed of 40% (APL1) and 20% (APL2) worm protein, a commercial diet, and no supplementary feed. Physicochemical parameters did not have a direct influence in shrimpbehavior. After six we...

  14. Soil Moisture Ocean Salinity (SMOS) salinity data validation over Malaysia coastal water

    International Nuclear Information System (INIS)

    Reba, M N M; Rosli, A Z; Rahim, N A

    2014-01-01

    The study of sea surface salinity (SSS) plays an important role in the marine ecosystem, estimation of global ocean circulation and observation of fisheries, aquaculture, coral reef and sea grass habitats. The new challenge of SSS estimation is to exploit the ocean surface brightness temperature (Tb) observed by the Microwave Imaging Radiometer with Aperture Synthesis (MIRAS) onboard the Soil Moisture Ocean Salinity (SMOS) satellite that is specifically designed to provide the best retrieval of ocean salinity and soil moisture using the L band of 1.4 GHz radiometer. Tb observed by radiometer is basically a function of the dielectric constant, sea surface temperature (SST), wind speed (U), incidence angle, polarization and SSS. Though, the SSS estimation is an ill-posed inversion problem as the relationship between the Tb and SSS is non-linear function. Objective of this study is to validate the SMOS SSS estimates with the ground-truth over the Malaysia coastal water. The LM iteratively determines the SSS of SMOS by the reduction of the sum of squared errors between Tb SMOS and Tb simulation (using in-situ) based on the updated geophysical triplet in the direction of the minimum of the cost function. The minimum cost function is compared to the desired threshold at each iteration and this recursive least square process updates the SST, U and SSS until the cost function converged. The designed LM's non-linear inversion algorithm simultaneously estimates SST, U and SSS and thus, map of SSS over Malaysia coastal water is produced from the regression model and accuracy assessment between the SMOS and in-situ retrieved SSS. This study found a good agreement in the validation with R square of 0.9 and the RMSE of 0.4. It is concluded that the non-linear inversion method is effective and practical to extract SMOS SSS, U and SST simultaneously

  15. Water stress monitoring using NDWI around deserts of China and Mongolia

    Science.gov (United States)

    Lee, Ga-Lam; Han, Kyung-Soo; Yeom, Jong-Min; Pi, Kyoung-Jin; Park, Soo-Jae

    2009-09-01

    The fluctuation of vegetation water condition around desert area is one of most important parameters to interpret the desertification expansion. United Nations reported that about 35 million square kilometers of land are subject to desertification. Historically, many parts of China have been suffered from severe desertification. This paper attempts an analysis for spatio-temporal variation characteristics of vegetation drought status around China and Mongolia desert with remotely sensed data. Time series images (1 January, 1999 - 31 December 2006) obtained from SPOT/VEGETATION were used to monitor inter-annual variability of water condition. SPOT/VEGETATION satellite, which has a fine temporal resolution and sensitive to vegetation growth, could be very useful to detect large scale dynamics of environmental changes and desertification progress. The main objective of the study is analyzing water status around China and Mongolia desert and predicting a risk area of desertification. In this study, NDWI (Normalized Difference Water Index) is used to monitor vegetation water condition (drought status) over the study area. To interpret the relationship between vegetation drought status and vigor, NDVI (Normalized Difference Vegetation Index) was employed in ensemble with NDWI. Annual total precipitation from NCEP/NCAR reanalysis data is used as subsidiary data. The study area from 73°36´E to 120°41´E longitude and from 30°81´N to 52°13´N longitude in northern China and whole Mongolia. NDWI value around desert has a range from -0.05 to -0.35 and NDWI values are decreased during the study period. Each year precipitation patterns are similar to yearly mean NDWI value. The study detected several areas where NDWI is dramatically decreased for 8 years, especially northeast part of Mongolian Gobi desert and southeast part of China Taklamakan desert.

  16. Grape Composition under Abiotic Constrains: Water Stress and Salinity

    Directory of Open Access Journals (Sweden)

    José M. Mirás-Avalos

    2017-05-01

    Full Text Available Water stress and increasing soil salt concentration represent the most common abiotic constrains that exert a negative impact on Mediterranean vineyards performance. However, several studies have proven that deficit irrigation strategies are able to improve grape composition. In contrast, irrigation with saline waters negatively affected yield and grape composition, although the magnitude of these effects depended on the cultivar, rootstock, phenological stage when water was applied, as well as on the salt concentration in the irrigation water. In this context, agronomic practices that minimize these effects on berry composition and, consequently, on wine quality must be achieved. In this paper, we briefly reviewed the main findings obtained regarding the effects of deficit irrigation strategies, as well as irrigation with saline water, on the berry composition of both red and white cultivars, as well as on the final wine. A meta-analysis was performed using published data for red and white varieties; a general liner model accounting for the effects of cultivar, rootstock, and midday stem water potential was able to explain up to 90% of the variability in the dataset, depending on the selected variable. In both red and white cultivars, berry weight, must titratable acidity and pH were fairly well simulated, whereas the goodness-of-fit for wine attributes was better for white cultivars.

  17. Growth and Water Relations of Sun-cured Tobacco Irrigated with Saline Water

    Directory of Open Access Journals (Sweden)

    Angelino G

    2014-12-01

    Full Text Available We have investigated the effects of saline irrigation on growth and water relations of two sun-cured tobacco genotypes, Xp102 and Px107, which belong to the Xanthia and Perustitza tobacco ecotypes, respectively. We compared three commercial sea salt concentrations of the irrigation water (0.25%, 0.5%, and 1% w/v plus a non-salinized control, corresponding to an electrical conductivity (ECw of 4.4, 8.5, 15.7, 0.5 dS m-1 and osmotic potentials of -0.22, -0.35, -0.73, -0.02 MPa, respectively. The ECsoil increased with the salinity of the irrigation water. At high salinity (1%, the soil where Px107 plants were grown showed a significantly higher salinity compared to the soil of Xp102. For both genotypes, the soil water content increased at increasing salinity and during the growth season. Increasing salinity progressively reduced the leaf turgor pressure and enhanced the cellular osmotic adjustment. The latter resulted to be more pronounced in Px107 compared to Xp102 (0.36 vs. 0.20 MPa. At higher salinity (0.5% and 1%, both genotypes showed reduced leaf surface area, dry matter accumulation, water use, net assimilation rate (NAR and crop growth rate (CGR. Px107 roots were more sensitive than shoot to salinity (3% reduction per dS m-1 and compared to Xp102 roots, which showed a reduced development only at 1% salinity. Assessment of plant salt tolerance according to the Maas and Hoffman model revealed a slope of 1-2% for both genotypes, indicating that these tobaccos are relatively more salt tolerant compared to other species.

  18. A framework for investigating the interactions between climate, dust, solar power generation and water desalination processes in Desert Climate

    Science.gov (United States)

    Siam, M. S.; Alqatari, S.; Ibrahim, H. D.; AlAloula, R. A.; Alrished, M.; AlSaati, A.; Eltahir, E. A. B.

    2016-12-01

    Increasing water demand in Saudi Arabia due to rapid population growth has forced the rapid expansion of seawater desalination plants in order to meet both current and future freshwater needs. Saudi Arabia has a huge potential for solar energy, hence, solar-powered desalination plants provide an opportunity to sustainably address the freshwater demand in the kingdom without relying on fossil fuels energy. However, the desert climate of Saudi Arabia and limited access to the open ocean imposes several challenges to the expansion and sustainability of solar-powered desalination plants. For example, the frequent and intense dust storms that occur in the region can degrade solar panels and significantly reduce their efficiency. Moreover, the high salinity Arabian Gulf is both the source of feedwater and sink of hypersaline discharge (brine) for many plants in the east of the Kingdom, and the brine may alter the salinity, temperature and movement of the water thereby reducing the quality of the feedwater to the desalination plants. Here, we propose a framework to investigate the different interactions between climate, dust, solar power generation and seawater desalination in order to identify optimal parameters such as locations of solar panels and seawater intake for sustainable implementation of solar-powered desalination plants. This framework integrates several numerical models including regional climate, hydrodynamics, Photovoltaics (PV) and Photovoltaic-Reverse Osmosis (PV-RO) models that are used to investigate these interactions for a solar-powered desalination plant at AlKhafji on the Northeastern coast of Saudi Arabia.

  19. Cyclic use of saline and non-saline water to increase water use efficiency and soil sustainability on drip irrigated maize in a semi-arid region

    Energy Technology Data Exchange (ETDEWEB)

    Hassanli, M.; Ebrahimian, H.

    2016-07-01

    Use of saline water for irrigation is a strategy to mitigate water shortage. The objective of this study was to investigate the impact of the cyclic and constant use of saline and non-saline water on drip irrigated maize yield and irrigation water use efficiency (IWUE). Nine field treatments were laid out based on alternative irrigation management of non-saline and saline water combinations. The treatments were: two salinity levels of 3.5 and 5.7 dS/m and freshwater (0.4 dS/m) application in every one, three and five saline water application (1:1, 3:1 and 5:1, respectively). Results showed that the 1:1 combination management was the best in terms of crop yield and IWUE. In this treatment, salt concentration at the end of growing season was not significantly changed compared to its initial condition. If off-season precipitation or leaching was available, the 3:1 and 5:1 treatments were appropriated. Highest and lowest values of IWUE were 15.3 and 8.7 kg/m3 for the 1:1 management using water salinity of 3.5 dS/m and the treatment of constant irrigation with water salinity of 5.7 dS/m, respectively. Under low off-season precipitations, artificial leaching is essential for land sustainability in most treatments.

  20. Cyclic use of saline and non-saline water to increase water use efficiency and soil sustainability on drip irrigated maize in a semi-arid region

    International Nuclear Information System (INIS)

    Hassanli, M.; Ebrahimian, H.

    2016-01-01

    Use of saline water for irrigation is a strategy to mitigate water shortage. The objective of this study was to investigate the impact of the cyclic and constant use of saline and non-saline water on drip irrigated maize yield and irrigation water use efficiency (IWUE). Nine field treatments were laid out based on alternative irrigation management of non-saline and saline water combinations. The treatments were: two salinity levels of 3.5 and 5.7 dS/m and freshwater (0.4 dS/m) application in every one, three and five saline water application (1:1, 3:1 and 5:1, respectively). Results showed that the 1:1 combination management was the best in terms of crop yield and IWUE. In this treatment, salt concentration at the end of growing season was not significantly changed compared to its initial condition. If off-season precipitation or leaching was available, the 3:1 and 5:1 treatments were appropriated. Highest and lowest values of IWUE were 15.3 and 8.7 kg/m3 for the 1:1 management using water salinity of 3.5 dS/m and the treatment of constant irrigation with water salinity of 5.7 dS/m, respectively. Under low off-season precipitations, artificial leaching is essential for land sustainability in most treatments.

  1. Origin of water in the Badain Jaran Desert, China: new insight from isotopes

    Science.gov (United States)

    Wu, Xiujie; Wang, Xu-Sheng; Wang, Yang; Hu, Bill X.

    2017-09-01

    To better understand the origin of water in the Badain Jaran Desert, China, water samples were collected from lakes, a spring and local unconfined aquifer for analyses of radiocarbon (14C), tritium (3H), stable hydrogen and oxygen isotope ratios (δ2H - δ18O), and d-excess values ( = δ2H - 8δ18O). A series of evaporation experiments were also conducted in the desert to examine how the isotopic signature of water may change during evaporation and infiltration under local environmental conditions. The results show that the lakes in the southeastern sand dune area are fed by groundwater discharging into the lakes and that local groundwater, on the other hand, is derived primarily from modern meteoric precipitation in the region. Although dissolved inorganic carbon (DIC) in groundwater yielded very old radiocarbon ages, the presence of detectable amounts of tritium in groundwater samples, together with their δ2H, δ18O and d-excess characteristics, strongly suggests that the old radiocarbon ages of DIC do not represent the residence time of water in the aquifer but are the result of addition of old DIC derived from dissolution of ancient carbonates in the aquifer. The data do not support the hypothesis that the water in the Badain Jaran Desert was sourced in remote mountains on the northern Tibetan Plateau. This study also finds no support for the hypothesis that present-day water resources in the desert were recharged by the precipitation that fell in the past during the early Holocene when the climate was much wetter than today. Instead, this study shows that both groundwater and lake water originated from meteoric precipitation in the region including mountainous areas adjacent to the desert under the modern climatic condition.

  2. Batteries for efficient energy extraction from a water salinity difference.

    Science.gov (United States)

    La Mantia, Fabio; Pasta, Mauro; Deshazer, Heather D; Logan, Bruce E; Cui, Yi

    2011-04-13

    The salinity difference between seawater and river water is a renewable source of enormous entropic energy, but extracting it efficiently as a form of useful energy remains a challenge. Here we demonstrate a device called "mixing entropy battery", which can extract and store it as useful electrochemical energy. The battery, containing a Na(2-x)Mn(5)O(10) nanorod electrode, was shown to extract energy from real seawater and river water and can be applied to a variety of salt waters. We demonstrated energy extraction efficiencies of up to 74%. Considering the flow rate of river water into oceans as the limiting factor, the renewable energy production could potentially reach 2 TW, or ∼13% of the current world energy consumption. The mixing entropy battery is simple to fabricate and could contribute significantly to renewable energy in the future.

  3. Batteries for Efficient Energy Extraction from a Water Salinity Difference

    KAUST Repository

    La Mantia, Fabio

    2011-04-13

    The salinity difference between seawater and river water is a renewable source of enormous entropic energy, but extracting it efficiently as a form of useful energy remains a challenge. Here we demonstrate a device called "mixing entropy battery", which can extract and store it as useful electrochemical energy. The battery, containing a Na2-xMn 5O10 nanorod electrode, was shown to extract energy from real seawater and river water and can be applied to a variety of salt waters. We demonstrated energy extraction efficiencies of up to 74%. Considering the flow rate of river water into oceans as the limiting factor, the renewable energy production could potentially reach 2 TW, or ∼13% of the current world energy consumption. The mixing entropy battery is simple to fabricate and could contribute significantly to renewable energy in the future. © 2011 American Chemical Society.

  4. Physical Deterioration of Egyptian Limestone Affected by Saline Water

    Directory of Open Access Journals (Sweden)

    Mohammed EL-GOHARY

    2013-12-01

    Full Text Available This study is the second in a series of experiments that describe the chemical, physical and thermal properties of archaeological limestone affected by salt and saline water in Egypt. This research aims to study the aggressive physical effects of different types of salts dominated in saline water and their different mechanisms on the acceleration of weathering processes that affect Egyptian limestone. It presents a multidisciplinary approach to characterize, at both micro/macro scales, the behavior of a limestone widely used as a construction material in most of Egyptian monuments when interacting with some types of salt solutions of various concentrations. A systematic optical, morphological, physical and mechanical analysis of the fresh and weathered stone samples were used to evaluate different characteristics through using scientific some techniques such as optical microscope (OP and scanning electron microscope (SEM. In addition to the using of some special computer programs that were used to define different physical and mechanical properties such as weight changes, bulk density, total porosity, water uptake, water content, thermal dilatation and abrasion resistant. The results proved that all investigated samples were gradually affected by the types of salinity paths and salt concentrations. These results will serve as a database for the future comparison of long term behavior of stones before and after the planned conservation of the entire area. So, it is pertinent to device some scientific methods and interventions to reduce all factors of salt effects and removing their harmful aspects from historic fabric of the archaeological buildings through some scientific recommendations

  5. Treatability of a Highly-Impaired, Saline Surface Water for Potential Urban Water Use

    Directory of Open Access Journals (Sweden)

    Frederick Pontius

    2018-03-01

    Full Text Available As freshwater sources of drinking water become limited, cities and urban areas must consider higher-salinity waters as potential sources of drinking water. The Salton Sea in the Imperial Valley of California has a very high salinity (43 ppt, total dissolved solids (70,000 mg/L, and color (1440 CU. Future wetlands and habitat restoration will have significant ecological benefits, but salinity levels will remain elevated. High salinity eutrophic waters, such as the Salton Sea, are difficult to treat, yet more desirable sources of drinking water are limited. The treatability of Salton Sea water for potential urban water use was evaluated here. Coagulation-sedimentation using aluminum chlorohydrate, ferric chloride, and alum proved to be relatively ineffective for lowering turbidity, with no clear optimum dose for any of the coagulants tested. Alum was most effective for color removal (28 percent at a dose of 40 mg/L. Turbidity was removed effectively with 0.45 μm and 0.1 μm microfiltration. Bench tests of Salton Sea water using sea water reverse osmosis (SWRO achieved initial contaminant rejections of 99 percent salinity, 97.7 percent conductivity, 98.6 percent total dissolved solids, 98.7 percent chloride, 65 percent sulfate, and 99.3 percent turbidity.

  6. Increased salinization of fresh water in the Northeastern United States

    Science.gov (United States)

    Kaushal, S.S.; Groffman, P.M.; Likens, G.E.; Belt, K.T.; Stack, W.P.; Kelly, V.R.; Band, L.E.; Fisher, G.T.

    2005-01-01

    Chloride concentrations are increasing at a rate that threatens the availability of fresh water in the northeastern United States. Increases in roadways and deicer use are now salinizing fresh waters, degrading habitat for aquatic organisms, and impacting large supplies of drinking water for humans throughout the region. We observed chloride concentrations of up to 25% of the concentration of seawater in streams of Maryland, New York, and New Hampshire during winters, and chloride concentrations remaining up to 100 times greater than unimpacted forest streams during summers. Mean annual chloride concentration increased as a function of impervious surface and exceeded tolerance for freshwater life in suburban and urban watersheds. Our analysis shows that if salinity were to continue to increase at its present rate due to changes in impervious surface coverage and current management practices, many surface waters in the northeastern United States would not be potable for human consumption and would become toxic to freshwater life within the next century. ?? 2005 by The National Academy of Sciences of the USA.

  7. Olive oil qualitative parameters after orchard irrigation with saline water.

    Science.gov (United States)

    Stefanoudaki, Evagelia; Williams, Mark; Chartzoulakis, Kostas; Harwood, John

    2009-02-25

    The effect of irrigation with saline water on oil quality was studied in the two olive ( Olea europaea L.) cultivars Koroneiki and Mastoidis, which are the main varieties grown extensively on the island of Crete. Plants (5 years old) were grown outdoors in containers, filled with freely drained light soil. Four treatments were applied, differing in the NaCl added to the irrigation water as follows: 0 (control) 50, 100, and 150 mM NaCl. Drip irrigation was applied regularly, during the dry season (from April to October). Plants in all treatments were irrigated when the soil-water potential reached -40 kPa at a depth of 30 cm. Data showed that increased NaCl levels in irrigation water resulted in a decrease in oil content in the fruits and an increase in total phenols and their secoiridoid derivatives in olive oils from harvested fruits. Furthermore, changes also took place in the composition of fatty acids and triacylglycerol molecular species. The extent of alterations was different for the two varieties and greater in cv. Koroneiki. This fitted with agronomic evidence that cv. Koroneiki is less saline-tolerant than cv. Mastoidis.

  8. Responses of three tomato cultivars to sea water salinity 1. Effect of ...

    African Journals Online (AJOL)

    The effect of sea water salinity (1500, 2500 and 3500 ppm) on the growth of tomato (Lycopersicon esculentum) cultivars (Trust, Grace and Plitz) was studied. The sea water salinity delayed seed germination and reduced germination percentage especially with increasing salinity level. Chlorophyll b content was higher than ...

  9. Variation in allocation of time, water and energy in Hoopoe Larks from the Arabian Desert

    NARCIS (Netherlands)

    Tieleman, BI; Williams, JB; Visser, GH

    2003-01-01

    1. Patterns of resource allocation in different times of the year can provide insights into the effects of simultaneous environmental constraints on reproduction and survival of desert birds. Field metabolic rate (FMR), water influx rate (WIR) and patterns of time allocation of Hoopoe Larks (Alaemon

  10. Contributions of groundwater conditions to soil and water salinization

    Science.gov (United States)

    Salama, Ramsis B.; Otto, Claus J.; Fitzpatrick, Robert W.

    Salinization is the process whereby the concentration of dissolved salts in water and soil is increased due to natural or human-induced processes. Water is lost through one or any combination of four main mechanisms: evaporation, evapotranspiration, hydrolysis, and leakage between aquifers. Salinity increases from catchment divides to the valley floors and in the direction of groundwater flow. Salinization is explained by two main chemical models developed by the authors: weathering and deposition. These models are in agreement with the weathering and depositional geological processes that have formed soils and overburden in the catchments. Five soil-change processes in arid and semi-arid climates are associated with waterlogging and water. In all represented cases, groundwater is the main geological agent for transmitting, accumulating, and discharging salt. At a small catchment scale in South and Western Australia, water is lost through evapotranspiration and hydrolysis. Saline groundwater flows along the beds of the streams and is accumulated in paleochannels, which act as a salt repository, and finally discharges in lakes, where most of the saline groundwater is concentrated. In the hummocky terrains of the Northern Great Plains Region, Canada and USA, the localized recharge and discharge scenarios cause salinization to occur mainly in depressions, in conjunction with the formation of saline soils and seepages. On a regional scale within closed basins, this process can create playas or saline lakes. In the continental aquifers of the rift basins of Sudan, salinity increases along the groundwater flow path and forms a saline zone at the distal end. The saline zone in each rift forms a closed ridge, which coincides with the closed trough of the groundwater-level map. The saline body or bodies were formed by evaporation coupled with alkaline-earth carbonate precipitation and dissolution of capillary salts. Résumé La salinisation est le processus par lequel la

  11. Effects of shallow water table, salinity and frequency of irrigation water on the date palm water use

    Science.gov (United States)

    Askri, Brahim; Ahmed, Abdelkader T.; Abichou, Tarek; Bouhlila, Rachida

    2014-05-01

    In southern Tunisia oases, waterlogging, salinity, and water shortage represent serious threats to the sustainability of irrigated agriculture. Understanding the interaction between these problems and their effects on root water uptake is fundamental for suggesting possible options of improving land and water productivity. In this study, HYDRUS-1D model was used in a plot of farmland located in the Fatnassa oasis to investigate the effects of waterlogging, salinity, and water shortage on the date palm water use. The model was calibrated and validated using experimental data of sap flow density of a date palm, soil hydraulic properties, water table depth, and amount of irrigation water. The comparison between predicted and observed data for date palm transpiration rates was acceptable indicating that the model could well estimate water consumption of this tree crop. Scenario simulations were performed with different water table depths, and salinities and frequencies of irrigation water. The results show that the impacts of water table depth and irrigation frequency vary according to the season. In summer, high irrigation frequency and shallow groundwater are needed to maintain high water content and low salinity of the root-zone and therefore to increase the date palm transpiration rates. However, these factors have no significant effect in winter. The results also reveal that irrigation water salinity has no significant effect under shallow saline groundwater.

  12. Potential foraging decisions by a desert ungulate to balance water and nutrient intake in a water-stressed environment

    Science.gov (United States)

    Gedir, Jay V.; Cain, James W.; Krausman, Paul R.; Allen, Jamison D.; Duff, Glenn C.; Morgart, John R.

    2016-01-01

    Arid climates have unpredictable precipitation patterns, and wildlife managers often provide supplemental water to help desert ungulates endure the hottest, driest periods. When surface water is unavailable, the only source of water for ungulates comes from the forage they consume, and they must make resourceful foraging decisions to meet their requirements. We compared two desert bighorn sheep (Ovis canadensis nelsoni) populations in Arizona, USA: a treatment population with supplemental water removed during treatment, and a control population. We examined whether sheep altered their seasonal diets without supplemental water. We calculated water and nutrient intake and metabolic water production from dry matter intake and forage moisture and nitrogen content, to determine whether sheep could meet their seasonal daily water and nutrient requirements solely from forage. Diets of sheep were higher in protein (all seasons) and moisture (autumn and winter) during treatment compared to pretreatment. During treatment, sheep diet composition was similar between the treatment and control populations, which suggests, under the climatic conditions of this study, water removal did not influence sheep diets. We estimated that under drought conditions, without any surface water available (although small ephemeral potholes would contain water after rains), female and male sheep would be unable to meet their daily water requirements in all seasons, except winter, when reproductive females had a nitrogen deficit. We determined that sheep could achieve water and nutrient balances in all seasons by shifting their total diet proportions by 8–55% from lower to higher moisture and nitrogen forage species. We elucidate how seasonal forage quality and foraging decisions by desert ungulates allow them to cope with their xeric and uncertain environment, and suggest that, with the forage conditions observed in our study area during this study period, providing supplemental water during

  13. Potential Foraging Decisions by a Desert Ungulate to Balance Water and Nutrient Intake in a Water-Stressed Environment.

    Directory of Open Access Journals (Sweden)

    Jay V Gedir

    Full Text Available Arid climates have unpredictable precipitation patterns, and wildlife managers often provide supplemental water to help desert ungulates endure the hottest, driest periods. When surface water is unavailable, the only source of water for ungulates comes from the forage they consume, and they must make resourceful foraging decisions to meet their requirements. We compared two desert bighorn sheep (Ovis canadensis nelsoni populations in Arizona, USA: a treatment population with supplemental water removed during treatment, and a control population. We examined whether sheep altered their seasonal diets without supplemental water. We calculated water and nutrient intake and metabolic water production from dry matter intake and forage moisture and nitrogen content, to determine whether sheep could meet their seasonal daily water and nutrient requirements solely from forage. Diets of sheep were higher in protein (all seasons and moisture (autumn and winter during treatment compared to pretreatment. During treatment, sheep diet composition was similar between the treatment and control populations, which suggests, under the climatic conditions of this study, water removal did not influence sheep diets. We estimated that under drought conditions, without any surface water available (although small ephemeral potholes would contain water after rains, female and male sheep would be unable to meet their daily water requirements in all seasons, except winter, when reproductive females had a nitrogen deficit. We determined that sheep could achieve water and nutrient balances in all seasons by shifting their total diet proportions by 8-55% from lower to higher moisture and nitrogen forage species. We elucidate how seasonal forage quality and foraging decisions by desert ungulates allow them to cope with their xeric and uncertain environment, and suggest that, with the forage conditions observed in our study area during this study period, providing supplemental

  14. Capillary rise simulation of saline waters of different concentrations in sandy soils

    Directory of Open Access Journals (Sweden)

    Natthawit Jitrapinate

    2016-06-01

    Full Text Available Soil salinity causes corrosion of engineering structures worldwide. The main cause of soil salinization is capillary rise of saline groundwater. Soil salinity can be mitigated once the capillary rise of saline groundwater in soils is understood. The objective of this paper is to present experimental results of capillary rising rates of different salt concentration waters in three sandy soils. Each sample comprised of a soil column 300-mm height and 50-mm in diameter steeped in a 25-mm deep saline water pool for a time period to allow for the capillary action to develop. The salinity strength varied from fresh water, EC = 2 dS/m, to medium saline (50, 100, and 150 dS/m, and to high saline water (200 dS/m. It was found that the highest rate of capillary rise occurred in medium saline waters, while the lowest is the fresh water. The very saline water has lower rate than the medium ones but higher than fresh water.

  15. Fog-basking behaviour and water collection efficiency in Namib Desert Darkling beetles

    OpenAIRE

    N?rgaard, Thomas; Dacke, Marie

    2010-01-01

    Abstract Background In the Namib Desert fog represents an alternative water source. This is utilised by Darkling beetles (Tenebrionidae) that employ different strategies for obtaining the fog water. Some dig trenches in the sand, while others use their own bodies as fog collectors assuming a characteristic fog-basking stance. Two beetle species from the genus Onymacris have been observed to fog-bask on the ridges of the sand dunes. These beetles all have smooth elytra surfaces, while another ...

  16. Age of ground water and the origin of its salinity in the Leba region

    International Nuclear Information System (INIS)

    Kwaterkiewicz, A.; Sadurski, A.; Zuber, A.

    1999-01-01

    Intensive exploitation of ground waters in the Leba region caused a strong increase of salinity, which on the basis of hydrochemistry, was supposed to result from the intrusion of the Baltic Sea water. Environmental isotope data revealed that water in the tertiary sediments is of glacial origin and its salinity is related to the admixture of ascending older waters. (author)

  17. The use of short rotation willows and poplars for the recycling of saline waste waters

    Science.gov (United States)

    Jaconette Mirck; Ronald S. Jr. Zalesny; Ioannis Dimitriou; Jill A. Zalesny; Timothy A. Volk; Warren E. Mabee

    2009-01-01

    The production of high-salinity waste waters by landfills and other waste sites causes environmental concerns. This waste water often contains high concentrations of sodium and chloride, which may end up in local ground and surface waters. Vegetation filter systems comprised of willows and poplars can be used for the recycling of saline waste water. These vegetation...

  18. Shrubland carbon sink depends upon winter water availability in the warm deserts of North America

    Science.gov (United States)

    Biederman, Joel A.; Scott, Russell L.; John A. Arnone,; Jasoni, Richard L.; Litvak, Marcy E.; Moreo, Michael T.; Papuga, Shirley A.; Ponce-Campos, Guillermo E.; Schreiner-McGraw, Adam P.; Vivoni, Enrique R.

    2018-01-01

    Global-scale studies suggest that dryland ecosystems dominate an increasing trend in the magnitude and interannual variability of the land CO2 sink. However, such model-based analyses are poorly constrained by measured CO2 exchange in open shrublands, which is the most common global land cover type, covering ∼14% of Earth’s surface. Here we evaluate how the amount and seasonal timing of water availability regulate CO2 exchange between shrublands and the atmosphere. We use eddy covariance data from six US sites across the three warm deserts of North America with observed ranges in annual precipitation of ∼100–400mm, annual temperatures of 13–18°C, and records of 2–8 years (33 site-years in total). The Chihuahuan, Sonoran and Mojave Deserts present gradients in both mean annual precipitation and its seasonal distribution between the wet-winter Mojave Desert and the wet-summer Chihuahuan Desert. We found that due to hydrologic losses during the wettest summers in the Sonoran and Chihuahuan Deserts, evapotranspiration (ET) was a better metric than precipitation of water available to drive dryland CO2 exchange. In contrast with recent synthesis studies across diverse dryland biomes, we found that NEP could not be directly predicted from ET due to wintertime decoupling of the relationship between ecosystem respiration (Reco) and gross ecosystem productivity (GEP). Ecosystem water use efficiency (WUE=GEP/ET) did not differ between winter and summer. Carbon use efficiency (CUE=NEP/GEP), however, was greater in winter because Reco returned a smaller fraction of carbon to the atmosphere (23% of GEP) than in summer (77%). Combining the water-carbon relations found here with historical precipitation since 1980, we estimate that lower average winter precipitation during the 21st century reduced the net carbon sink of the three deserts by an average of 6.8TgC yr1. Our results highlight that winter precipitation is critical to the annual carbon balance of these

  19. Water recovery from saline streams produced by electrodialysis.

    Science.gov (United States)

    Andrade Becheleni, Emily Mayer; Borba, Ricardo Perobelli; Seckler, Marcelo Martins; Ferreira Rocha, Sônia Denise

    2015-01-01

    Advances in technologies to enable water reuse in industry have been the objective of many research efforts, mainly due to the need to reduce the use of natural resources and due to factors related to their availability. This paper evaluates the crystallization of salts from petrochemical saline waste to achieve zero water discharge by the recovery of water and dissolved salts as a solid mixture. In line with process symbiosis, the recovered water should be suitable for use as cooling water in heat exchangers. Vacuum evaporative crystallization, at the batch scale, was used to remove the salts present in the concentrated stream from reverse electrodialysis of pretreated wastewater by a biological process. The partition of organic compounds in the feed solution between the condensate and the mother liquor was obtained from measurements of the total organic carbon and total nitrogen in the solutions. The solid phases formed experimentally are compared with those predicted by chemical modelling by PHREEQC. The recovered water presented almost 50 times less total dissolved solids than the feed stream (from 2100 to 44 mg/L). Calcium sulphate hydrate, calcium sulphate and sodium chloride were the majority crystalline phases formed, in accordance with the modelling by PHREEQC.

  20. Desert water harvesting to benefit wildlife: a simple, cheap, and durable sub-surface water harvester for remote locations.

    Science.gov (United States)

    Rice, William E

    2004-12-01

    A sub-surface desert water harvester was constructed in the sagebrush steppe habitat of south-central Idaho, U.S.A. The desert water harvester utilizes a buried micro-catchment and three buried storage tanks to augment water for wildlife during the dry season. In this region, mean annual precipitation (MAP) ranges between about 150-250 mm (6"-10"), 70% of which falls during the cold season, November to May. Mid-summer through early autumn, June through October, is the dry portion of the year. During this period, the sub-surface water harvester provides supplemental water for wildlife for 30-90 days, depending upon the precipitation that year. The desert water harvester is constructed with commonly available, "over the counter" materials. The micro-catchment is made of a square-shaped, 20 mL. "PERMALON" polyethylene pond liner (approximately 22.9 m x 22.9 m = 523 m2) buried at a depth of about 60 cm. A PVC pipe connects the harvester with two storage tanks and a drinking trough. The total capacity of the water harvester is about 4777 L (1262 U.S. gallons) which includes three underground storage tanks, a trough and pipes. The drinking trough is refined with an access ramp for birds and small animals. The technology is simple, cheap, and durable and can be adapted to other uses, e.g. drip irrigation, short-term water for small livestock, poultry farming etc. The desert water harvester can be used to concentrate and collect water from precipitation and run-off in semi-arid and arid regions. Water harvested in such a relatively small area will not impact the ground water table but it should help to grow small areas of crops or vegetables to aid villagers in self-sufficiency.

  1. Energetics and water relations ofN amib desert rodents

    African Journals Online (AJOL)

    All the Namib rodents investigated, except Petromus, can survive without water on a diet of air-dried seed. Water turnover rates of these animals in the laboratory confirmed their low water requirements. Field water turnover rates were remarkably low, probably because Petromyscus and. Aethomys aestivate and Petromus ...

  2. Cyanobacteria and cyanotoxins are present in drinking water impoundments and groundwater wells in desert environments.

    Science.gov (United States)

    Chatziefthimiou, Aspassia D; Metcalf, James S; Glover, W Broc; Banack, Sandra A; Dargham, Soha R; Richer, Renee A

    2016-05-01

    Desert environments and drylands experience a drastic scarcity of water resources. To alleviate dependence on freshwater for drinking water needs, countries have invested in infrastructure development of desalination plants. Collectively, the countries of the Arabian Gulf produce 45% of the world's desalinated water, which is stored in dams, mega-reservoirs and secondary house water tanks to secure drinking water beyond daily needs. Improper storage practices of drinking water in impoundments concomitant with increased temperatures and light penetration may promote the growth of cyanobacteria and accumulation of cyanotoxins. To shed light on this previously unexplored research area in desert environments, we examined drinking and irrigation water of urban and rural environments to determine whether cyanobacteria and cyanotoxins are present, and what are the storage and transportation practices as well as the environmental parameters that best predict their presence. Cyanobacteria were present in 80% of the urban and 33% of the rural water impoundments. Neurotoxins BMAA, DAB and anatoxin-a(S) were not detected in any of the water samples, although they have been found to accumulate in the desert soils, which suggests a bioaccumulation potential if they are leached into the aquifer. A toxic BMAA isomer, AEG, was found in 91.7% of rural but none of the urban water samples and correlated with water-truck transportation, light exposure and chloride ions. The hepatotoxic cyanotoxin microcystin-LR was present in the majority of all sampled impoundments, surpassing the WHO provisional guideline of 1 μg/l in 30% of the urban water tanks. Finally, we discuss possible management strategies to improve storage and transportation practices in order to minimize exposure to cyanobacteria and cyanotoxins, and actions to promote sustainable use of limited water resources. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Root water uptake under non-uniform transient salinity and water stress

    NARCIS (Netherlands)

    Homaee, M.

    1999-01-01

    The study described in this thesis focuses on the quantitative understanding of water uptake by roots under separate and combined salinity and water stresses. The major difficulty in solving Richards' equation stems from the lack of a sink term function that adequately

  4. Efficiency of three halophyte species in removing nutrients from saline water

    NARCIS (Netherlands)

    Lange, de H.J.; Paulissen, M.P.C.P.

    2016-01-01

    Saline wetlands may be well suited for purifying contaminated water from saline agriculture and aquaculture or from freshwater-based agriculture in areas subject to increased salinity. However, case studies on the nutrient removal efficiency of halophyte species are scarce, especially for

  5. Factors controlling As and U in shallow ground water, southern Carson Desert, Nevada

    Science.gov (United States)

    Welch, A.H.; Lico, M.S.

    1998-01-01

    Unusually high As and U concentrations (> 100 ??g/L) are widespread in shallow ground water beneath the southern Carson Desert. The high concentrations, which locally exceed 1000 ??g/L, are of concern from a human health standpoint because the shallow ground water is used for domestic supply. Possible affects on wildlife are also of concern because the ground water flows into shallow lakes and marshes within wildlife refuges. Arsenic and U concentrations in ground water of the southern Carson Desert appear to be affected by evaporative concentration, redox reactions, and adsorption. The relation of these elements with Cl suggest that most of the high concentrations can be attributed to evaporative concentration of Carson River water, the primary source of recharge. Some ground water contains higher As and U concentrations that cannot be explained by evaporative concentration alone. Oxidation-reduction reactions, involving metal oxides and sedimentary-organic matter, appear to contribute As, U, inorganic C, Fe and Mn to the ground water. Arsenic in Fe-oxide was confirmed by chemical extraction and is consistent with laboratory adsorption studies. Uranium in both sedimentary-organic C and Fe-oxide coatings has been confirmed by fission tracks and petrographic examination. Arsenic concentrations in the ground water and chemical extracts of aquifer sediments are broadly consistent with adsorption as a control on some dissolved As concentrations. An apparent loss of As from some ground water as evaporative concentration proceeds is consistent with adsorption as a control on As. However, evidence for adsorption should be viewed with caution, because the adsorption model used values for the adsorbent that have not been shown to be valid for the aquifer sediments throughout the southern Carson Desert. Hydrologic and geochemical conditions in the Carson Desert are similar to other areas with high As and U concentrations in ground water, including the Salton Sea basin and

  6. Analytical steady-state solutions for water-limited cropping systems using saline irrigation water

    Science.gov (United States)

    Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.; Suarez, D. L.

    2014-12-01

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems modeling framework that accounts for reduced plant water uptake due to root zone salinity. Two explicit, closed-form analytical solutions for the root zone solute concentration profile are obtained, corresponding to two alternative functional forms of the uptake reduction function. The solutions express a general relationship between irrigation water salinity, irrigation rate, crop salt tolerance, crop transpiration, and (using standard approximations) crop yield. Example applications are illustrated, including the calculation of irrigation requirements for obtaining targeted submaximal yields, and the generation of crop-water production functions for varying irrigation waters, irrigation rates, and crops. Model predictions are shown to be mostly consistent with existing models and available experimental data. Yet the new solutions possess advantages over available alternatives, including: (i) the solutions were derived from a complete physical-mathematical description of the system, rather than based on an ad hoc formulation; (ii) the analytical solutions are explicit and can be evaluated without iterative techniques; (iii) the solutions permit consideration of two common functional forms of salinity induced reductions in crop water uptake, rather than being tied to one particular representation; and (iv) the utilized modeling framework is compatible with leading transient-state numerical models.

  7. Kinetics and Mechanisms of Calcite Reactions with Saline Waters

    Energy Technology Data Exchange (ETDEWEB)

    Gorman, Brian P [Colorado School of Mines, Golden, CO (United States)

    2015-09-02

    Project Description: The general objective of the proposed research is to determine the kinetics and mechanisms of calcite reactions with saline waters over a wide range of saline water composition, pCO2, and modest ranges in T and P. This will be accomplished by studying both reaction rates and solubility from changes in solution chemistry, and making nanoscale observations of calcite precipitate surface morphology and composition at the micro-to-nano-scale to provide an understanding of controlling reaction mechanisms and pathways. The specific objectives necessary to reach the general objective are: a) determination of how pCO2, Ca2+, ionic strength and “foreign” ions influence reaction rates; and b) investigate the influence of these parameters on apparent kinetic solubility from dissolution and precipitation reactions. This information will clearly be central to the construction of reliable reaction-transport models to predict reservoir and formation response to increased CO2 in saline waters. This program was initially collaborative with John Morse at Texas A&M, however his passing shortly after the beginning of this program resulted in abbreviated research time and effort. Summary of Results: Early studies using electron microscopy and spectroscopy indicated that carbonate precipitation from natural seawater (NSW) conditions onto aragonite substrates was mediated by a surface amorphous calcium carbonate layer. It was hypothesized that this ACC layer (observed after < 5days reaction time) was responsible for the abnormal reaction kinetics and also served as a metastable seed layer for growth of epitaxial aragonite. Further studies of the ACC formation mechanism indicated a strong dependence on the Mg concentration in solution. Subsequent studies at shorter times (10 hrs) on calcite substrates and in a wide range of supersaturation conditions did not indicate any ACC layer. Instead, an epitaxial layer by layer

  8. Metabolomic response of Calotropis procera growing in the desert to changes in water availability.

    Directory of Open Access Journals (Sweden)

    Ahmed Ramadan

    Full Text Available Water availability is a major limitation for agricultural productivity. Plants growing in severe arid climates such as deserts provide tools for studying plant growth and performance under extreme drought conditions. The perennial species Calotropis procera used in this study is a shrub growing in many arid areas which has an exceptional ability to adapt and be productive in severe arid conditions. We describe the results of studying the metabolomic response of wild C procera plants growing in the desert to a one time water supply. Leaves of C. procera plants were taken at three time points before and 1 hour, 6 hours and 12 hours after watering and subjected to a metabolomics and lipidomics analysis. Analysis of the data reveals that within one hour after watering C. procera has already responded on the metabolic level to the sudden water availability as evidenced by major changes such as increased levels of most amino acids, a decrease in sucrose, raffinose and maltitol, a decrease in storage lipids (triacylglycerols and an increase in membrane lipids including photosynthetic membranes. These changes still prevail at the 6 hour time point after watering however 12 hours after watering the metabolomics data are essentially indistinguishable from the prewatering state thus demonstrating not only a rapid response to water availability but also a rapid response to loss of water. Taken together these data suggest that the ability of C. procera to survive under the very harsh drought conditions prevailing in the desert might be associated with its rapid adjustments to water availability and losses.

  9. Desert Beetle-Inspired Superwettable Patterned Surfaces for Water Harvesting.

    Science.gov (United States)

    Yu, Zhenwei; Yun, Frank F; Wang, Yanqin; Yao, Li; Dou, Shixue; Liu, Kesong; Jiang, Lei; Wang, Xiaolin

    2017-09-01

    With the impacts of climate change and impending crisis of clean drinking water, designing functional materials for water harvesting from fog with large water capacity has received much attention in recent years. Nature has evolved different strategies for surviving dry, arid, and xeric conditions. Nature is a school for human beings. In this contribution, inspired by the Stenocara beetle, superhydrophilic/superhydrophobic patterned surfaces are fabricated on the silica poly(dimethylsiloxane) (PDMS)-coated superhydrophobic surfaces using a pulsed laser deposition approach with masks. The resultant samples with patterned wettability demonstrate water-harvesting efficiency in comparison with the silica PDMS-coated superhydrophobic surface and the Pt nanoparticles-coated superhydrophilic surface. The maximum water-harvesting efficiency can reach about 5.3 g cm -2 h -1 . Both the size and the percentage of the Pt-coated superhydrophilic square regions on the patterned surface affect the condensation and coalescence of the water droplet, as well as the final water-harvesting efficiency. The present water-harvesting strategy should provide an avenue to alleviate the water crisis facing mankind in certain arid regions of the world. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Chihuahua: a water reuse case in the desert.

    Science.gov (United States)

    Espino, M S; Navarro, C J; Pérez, J M

    2004-01-01

    Water supply for all kind of uses in Chihuahua is mainly groundwater. During the last decade this city has been damaged with a heavy hydrologic crisis because of a persistent drought. This came up with the overexploitation of groundwater aquifers; therefore a deficit between demand and offer was done. To minimize this problem the government authorities have started an integral plan of optimizing hydrologic resources which considers the treatment of wastewater and the use of reclaimed water. The secondary wastewater treatment facility of the city treats about 30,000 m3/d of a wastewater with high organic contents, and produces an effluent with low concentration of suspended solids, organic matter, fats, detergents, and metals. Reclaimed water is conveyed toward strategic sites for the irrigation of great green areas in sport clubs, educational institutions and industrial zones, besides of its utilization on some manufacturing processes, road service, and also over construction industry. The potential reuse of this water goes farther from those activities; the treatment of the secondary effluent until the required levels of the water-bearing recharge criteria are met for drinking water supply is considered as the next step to achieve through a suitable planning strategy for the best integral resource advantage.

  11. Anthropogenic water sources and the effects on Sonoran Desert small mammal communities

    Directory of Open Access Journals (Sweden)

    Aaron B. Switalski

    2017-11-01

    Full Text Available Anthropogenic water sources (AWS are developed water sources used as a management tool for desert wildlife species. Studies documenting the effects of AWS are often focused on game species; whereas, the effects on non-target wildlife are less understood. We used live trapping techniques to investigate rodent abundance, biomass, and diversity metrics near AWS and paired control sites; we sampled vegetation to determine rodent-habitat associations in the Sauceda Mountains of the Sonoran Desert in Arizona. A total of 370 individual mammals representing three genera and eight species were captured in 4,800 trap nights from winter 2011 to spring 2012. A multi-response permutation procedure was used to identify differences in small mammal community abundance and biomass by season and treatment. Rodent abundance, biomass, and richness were greater at AWS compared to control sites. Patterns of abundance and biomass were driven by the desert pocket mouse (Chaetodipus penicillatus which was the most common capture and two times more numerous at AWS compared to controls. Vegetation characteristics, explored using principal components analysis, were similar between AWS and controls. Two species that prefer vegetation structure, Bailey’s pocket mouse (C. baileyi and white-throated woodrat (Neotoma albigula, had greater abundances and biomass near AWS and were associated with habitat having high cactus density. Although small mammals do not drink free-water, perhaps higher abundances of some species of desert rodents at AWS could be related to artificial structure associated with construction or other resources. Compared to the 30-year average of precipitation for the area, the period of our study occurred during a dry winter. During dry periods, perhaps AWS provide resources to rodents related to moisture.

  12. [Effect of shifting sand burial on evaporation reduction and salt restraint under saline water irrigation in extremely arid region].

    Science.gov (United States)

    Zhang, Jian-Guo; Zhao, Ying; Xu, Xin-Wen; Lei, Jia-Qiang; Li, Sheng-Yu; Wang, Yong-Dong

    2014-05-01

    The Taklimakan Desert Highway Shelterbelt is drip-irrigated with high saline groundwater (2.58-29.70 g x L(-1)), and shifting sand burial and water-salt stress are most common and serious problems in this region. So it is of great importance to study the effect of shifting sand burial on soil moisture evaporation, salt accumulation and their distribution for water saving, salinity restraint, and suitable utilization of local land and water resources. In this study, Micro-Lysimeters (MLS) were used to investigate dynamics of soil moisture and salt under different thicknesses of sand burial (1, 2, 3, 4, and 5 cm), and field control experiments of drip-irrigation were also carried out to investigate soil moisture and salt distribution under different thicknesses of shifting sand burial (5, 10, 15, 20, 25, 30, 35, and 40 cm). The soil daily and cumulative evaporation decreased with the increase of sand burial thickness in MLS, cumulative evaporation decreased by 2.5%-13.7% compared with control. And evaporative inhibiting efficiency increased with sand burial thickness, evaporative inhibiting efficiency of 1-5 cm sand burial was 16.7%-79.0%. Final soil moisture content beneath the interface of sand burial increased with sand burial thickness, and it increased by 2.5%-13.7% than control. The topsoil EC of shifting sand in MLS decreased by 1.19-6.00 mS x cm(-1) with the increasing sand burial thickness, whereas soil salt content beneath the interface in MLS increased and amplitude of the topsoil salt content was higher than that of the subsoil. Under drip-irrigation with saline groundwater, average soil moisture beneath the interface of shifting sand burial increased by 0.4% -2.0% compare with control, and the highest value of EC was 7.77 mS x cm(-1) when the sand burial thickness was 10 cm. The trend of salt accumulation content at shifting sand surface increased firstly, and then decreased with the increasing sand burial thickness. Soil salt contents beneath the

  13. Influence of Biochar Amendment on Soil Water Characteristics and Crop Growth Enhancement Under Salinity Stress

    OpenAIRE

    Gamareldawla H.D

    2017-01-01

    Salinity is an important environmental constraint to crop productivity in arid and semi-arid regions of the world. Most crop plants, including tomato (Lycopersicon esculentum Mill), are sensitive to salinity throughout the ontogeny of the plant. Biochar was used in the present study to improve the available water content (AWC), growth, yield and irrigation water use efficiency of tomato plant under saline soil condition. The biochar was applied at the rates of, 0%, 2% and 4% w/w and expressed...

  14. Influence of Biochar Amendment on Soil Water Characteristics and Crop Growth Enhancement Under Salinity Stress

    OpenAIRE

    Agbna , Gamareldawla ,; Ali1 , Abubaker ,; Bashir , Amir ,; Eltoum , Farid; Hassan , Mohamed ,

    2017-01-01

    International audience; Salinity is an important environmental constraint to crop productivity in arid and semi-arid regions of the world. Most crop plants, including tomato (Lycopersicon esculentum Mill), are sensitive to salinity throughout the ontogeny of the plant. Biochar was used in the present study to improve the available water content (AWC), growth, yield and irrigation water use efficiency of tomato plant under saline soil condition. The biochar was applied at the rates of, 0%, 2% ...

  15. Water and salinity stress in grapevines: early and late changes in transcript and metabolite profiles.

    Science.gov (United States)

    Cramer, Grant R; Ergül, Ali; Grimplet, Jerome; Tillett, Richard L; Tattersall, Elizabeth A R; Bohlman, Marlene C; Vincent, Delphine; Sonderegger, Justin; Evans, Jason; Osborne, Craig; Quilici, David; Schlauch, Karen A; Schooley, David A; Cushman, John C

    2007-04-01

    Grapes are grown in semiarid environments, where drought and salinity are common problems. Microarray transcript profiling, quantitative reverse transcription-PCR, and metabolite profiling were used to define genes and metabolic pathways in Vitis vinifera cv. Cabernet Sauvignon with shared and divergent responses to a gradually applied and long-term (16 days) water-deficit stress and equivalent salinity stress. In this first-of-a-kind study, distinct differences between water deficit and salinity were revealed. Water deficit caused more rapid and greater inhibition of shoot growth than did salinity at equivalent stem water potentials. One of the earliest responses to water deficit was an increase in the transcript abundance of RuBisCo activase (day 4), but this increase occurred much later in salt-stressed plants (day 12). As water deficit progressed, a greater number of affected transcripts were involved in metabolism, transport, and the biogenesis of cellular components than did salinity. Salinity affected a higher percentage of transcripts involved in transcription, protein synthesis, and protein fate than did water deficit. Metabolite profiling revealed that there were higher concentrations of glucose, malate, and proline in water-deficit-treated plants as compared to salinized plants. The metabolite differences were linked to differences in transcript abundance of many genes involved in energy metabolism and nitrogen assimilation, particularly photosynthesis, gluconeogenesis, and photorespiration. Water-deficit-treated plants appear to have a higher demand than salinized plants to adjust osmotically, detoxify free radicals (reactive oxygen species), and cope with photoinhibition.

  16. Further observations on the water relations ofProsopis tamarugo of the northern Atacama desert.

    Science.gov (United States)

    Mooney, H A; Gulmon, S L; Rundel, P W; Ehleringer, J

    1980-01-01

    Prosopis tamarugo, a tree native to the Atacama desert of Chile apparently has unique water relations. It is proposed that in its native habitat, where there is essentially no precipitation, establishment occurs during the rare flooding periods, with water coming as runoff from the Andes. These plants subsequently exist as phreatophytes tapping the relatively shallow ground water. Although phreatophytic, the plants appears to come under increasing drought stress as the growing season progresses. Because of the very low water potentials of the salty surface soils, water evidently moves from the plant into the soil under certain conditions. This water may be reabsorbed subsequently and used by the plant as the water table capillary fringe is depleted toward the end of the leafy period.

  17. Interacting vegetative and thermal contributions to water movement in desert soil

    Science.gov (United States)

    Garcia, C.A.; Andraski, Brian J.; Stonestrom, David A.; Cooper, C.A.; Šimůnek, J.; Wheatcraft, S.W.

    2011-01-01

    Thermally driven water-vapor flow can be an important component of total water movement in bare soil and in deep unsaturated zones, but this process is often neglected when considering the effects of soil–plant–atmosphere interactions on shallow water movement. The objectives of this study were to evaluate the coupled and separate effects of vegetative and thermal-gradient contributions to soil water movement in desert environments. The evaluation was done by comparing a series of simulations with and without vegetation and thermal forcing during a 4.7-yr period (May 2001–December 2005). For vegetated soil, evapotranspiration alone reduced root-zone (upper 1 m) moisture to a minimum value (25 mm) each year under both isothermal and nonisothermal conditions. Variations in the leaf area index altered the minimum storage values by up to 10 mm. For unvegetated isothermal and nonisothermal simulations, root-zone water storage nearly doubled during the simulation period and created a persistent driving force for downward liquid fluxes below the root zone (total net flux ~1 mm). Total soil water movement during the study period was dominated by thermally driven vapor fluxes. Thermally driven vapor flow and condensation supplemented moisture supplies to plant roots during the driest times of each year. The results show how nonisothermal flow is coupled with plant water uptake, potentially influencing ecohydrologic relations in desert environments.

  18. Radium Adsorption to Iron Bearing Minerals in Variable Salinity Waters

    Science.gov (United States)

    Chen, M.; Kocar, B. D.

    2014-12-01

    Radium is a common, naturally occurring radioactive metal found in many subsurface environments. Radium isotopes are a product of natural uranium and thorium decay, and are particularly abundant within groundwaters where minimal flux leads to accumulation within porewaters. Radium has been used as a natural tracer to estimate submarine groundwater discharge (SGD) [1], where the ratios of various radium isotopes are used to estimate total groundwater flux to and from the ocean [2]. Further, it represents a substantial hazard in waste water produced after hydraulic fracturing for natural gas extraction [3], resulting in a significant risk of environmental release and increased cost for water treatment or disposal. Adsorption to mineral surfaces represents a primary pathway of radium retention within subsurface environments. For SGD studies, it is important to understand adsorption processes to correctly estimate GW fluxes, while in hydraulic fracturing, radium adsorption to aquifer solids will mediate the activities of radium within produced water. While some studies of radium adsorption to various minerals have been performed [4], there is a limited understanding of the surface chemistry of radium adsorption, particularly to iron-bearing minerals such as pyrite, goethite and ferrihydrite. Accordingly, we present the results of sorption experiments of radium to a suite of iron-bearing minerals representative of those found within deep saline and near-surface (freshwater) aquifers, and evaluate impacts of varying salinity solutions through the use of artificial groundwater, seawater, and shale formation brine. Further, we explore the impacts of pyrite oxidation and ferrihydrite transformation to other iron-bearing secondary minerals on the retention of radium. This work lays the groundwork for further study of radium use as a tracer for SGD, as well as understanding mechanisms of radium retention and release from deep aquifer materials following hydraulic fracturing

  19. Geophysical study for saline water intrusion in a coastal alluvial terrain

    Science.gov (United States)

    Choudhury, Kalpan; Saha, D. K.; Chakraborty, P.

    2001-03-01

    Geophysical investigations comprising electrical resistivity and shallow seismic refraction methods have been employed in the alluvial coastal belt of Digha, in the Eastern India for environmental study, to investigate the nature and status of subsurface saline water contamination. Geophysical surveys have delineated different subsurface geological formations such as dune sand, top sandy soil, saline sand and saline clay on the basis of their characteristic resistivity and velocity signatures. It is also inferred from geophysical interpretation that the thickness of the near-surface saline zone decreases inland away from the shore. Fortunately for Digha, clay layers present at different subsurface levels, which have probable extensions under the sea, have acted as barriers against any large-scale saline water intrusion at depth, even though pockets of saline/brackish zones have been interpreted in the subsurface. Clay formations are predominant up to a depth of about 60 m in the area below which an aquifer zone has been demarcated. A few locales that are already saline or are vulnerable for saline water intrusion have been identified at different depth levels and these zones should be avoided for ground water development. Further, several comparatively safe zones where ground water can be effectively exploited, have been delineated in the area. It has been observed that geophysical methods are highly useful in the environmental study for assessing saline water intrusion in alluvial terrain even in the presence of thick clay formations.

  20. Influence of salinity and water content on soil microorganisms

    OpenAIRE

    Yan, Nan; Marschner, Petra; Cao, Wenhong; Zuo, Changqing; Qin, Wei

    2015-01-01

    Salinization is one of the most serious land degradation problems facing world. Salinity results in poor plant growth and low soil microbial activity due to osmotic stress and toxic ions. Soil microorganisms play a pivotal role in soils through mineralization of organic matter into plant available nutrients. Therefore it is important to maintain high microbial activity in soils. Salinity tolerant soil microbes counteract osmotic stress by synthesizing osmolytes which allows them to maintain t...

  1. Effect of volume loading with water, normal saline, palm wine and ...

    African Journals Online (AJOL)

    A comparative study of the diuretic effect of water, normal saline, palm wine and Lipton tea was carried out on forty (40) randomly selected, apparently normal undergraduate students of Medicine and Pharmacy at the University of Uyo, Nigeria. One and a half (1.5) litres of water, normal saline, palm wine and Lipton tea were ...

  2. A fast alternative to core plug tests for optimising injection water salinity for EOR

    DEFF Research Database (Denmark)

    Hassenkam, Tue; Andersson, Martin Peter; Hilner, Emelie Kristin Margareta

    2014-01-01

    Core tests have demonstrated that decreasing the salinity of injection water can increase oil recovery. Although recovery is enhanced by simply decreasing salt content, optimising injection water salinty would offer a clear economic advantage for several reasons. Too low salinity risks swelling o...

  3. The effect of drinking water salinity on blood pressure in young adults of coastal Bangladesh.

    Science.gov (United States)

    Talukder, Mohammad Radwanur Rahman; Rutherford, Shannon; Phung, Dung; Islam, Mohammad Zahirul; Chu, Cordia

    2016-07-01

    More than 35 million people in coastal Bangladesh are vulnerable to increasing freshwater salinization. This will continue to affect more people and to a greater extent as climate change projections are realised in this area in the future. However the evidence for health effects of consuming high salinity water is limited. This research examined the association between drinking water salinity and blood pressure in young adults in coastal Bangladesh. We conducted a cross-sectional study during May-June 2014 in a rural coastal sub-district of Bangladesh. Data on blood pressure (BP) and salinity of potable water sources was collected from 253 participants aged 19-25 years. A linear regression method was used to examine the association between water salinity exposure categories and systolic BP (SBP) and diastolic BP (DBP) level. Sixty five percent of the study population were exposed to highly saline drinking water above the Bangladesh standard (600 mg/L and above). Multivariable linear regression analyses identified that compared to the low water salinity exposure category (water salinity category (>600 mg/L), had statistically significantly higher SBP (B 3.46, 95% CI 0.75, 6.17; p = 0.01) and DBP (B 2.77, 95% CI 0.31, 5.24; p = 0.03). Our research shows that elevated salinity in drinking water is associated with higher BP in young coastal populations. Blood pressure is an important risk factor of hypertension and cardiovascular diseases. Given the extent of salinization of freshwater in many low-lying countries including in Bangladesh, and the likely exacerbation related to climate change-induced sea level rise, implementation of preventative strategies through dietary interventions along with promotion of low saline drinking water must be a priority in these settings. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Drinking cholera: salinity levels and palatability of drinking water in coastal Bangladesh.

    Science.gov (United States)

    Grant, Stephen Lawrence; Tamason, Charlotte Crim; Hoque, Bilqis Amin; Jensen, Peter Kjaer Mackie

    2015-04-01

    To measure the salinity levels of common water sources in coastal Bangladesh and explore perceptions of water palatability among the local population to investigate the plausibility of linking cholera outbreaks in Bangladesh with ingestion of saline-rich cholera-infected river water. Hundred participants took part in a taste-testing experiment of water with varying levels of salinity. Salinity measurements were taken of both drinking and non-drinking water sources. Informal group discussions were conducted to gain an in-depth understanding of water sources and water uses. Salinity levels of non-drinking water sources suggest that the conditions for Vibrio cholerae survival exist 7-8 days within the local aquatic environment. However, 96% of participants in the taste-testing experiment reported that they would never drink water with salinity levels that would be conducive to V. cholerae survival. Furthermore, salinity levels of participant's drinking water sources were all well below the levels required for optimal survival of V. cholerae. Respondents explained that they preferred less salty and more aesthetically pleasing drinking water. Theoretically, V. cholerae can survive in the river systems in Bangladesh; however, water sources which have been contaminated with river water are avoided as potential drinking water sources. Furthermore, there are no physical connecting points between the river system and drinking water sources among the study population, indicating that the primary driver for cholera cases in Bangladesh is likely not through the contamination of saline-rich river water into drinking water sources. © 2015 John Wiley & Sons Ltd.

  5. Enhanced remediation of an oily sludge with saline water

    African Journals Online (AJOL)

    UFUOMA

    biodegradation of oily sludge by hydrocarbon utilizing bacteria (Bacillus subtilis) at salinity (NaCl ... petroleum waste. In recent times, several literatures have shown that bioremediation has high potentials for restoring polluted media with least negative impact on the ..... salinity, bacterial consortium is highly stable in immo-.

  6. Chemical Analyses of Ground Water in the Carson Desert near Stillwater, Churchill County, Nevada, 2005

    Science.gov (United States)

    Fosbury, DeEtta; Walker, Mark; Stillings, Lisa L.

    2008-01-01

    This report presents the chemical analyses of ground-water samples collected in 2005 from domestic wells located in the Stillwater area of the Carson Desert (fig. 1). These data were evaluated for evidence of mixing with nearby geothermal waters (Fosbury, 2007). That study used several methods to identify mixing zones of ground and geothermal waters using trace elements, chemical equilibria, water temperature, geothermometer estimates, and statistical techniques. In some regions, geothermal sources influence the chemical quality of ground water used for drinking water supplies. Typical geothermal contaminants include arsenic, mercury, antimony, selenium, thallium, boron, lithium, and fluoride (Webster and Nordstrom, 2003). The Environmental Protection Agency has established primary drinking water standards for these, with the exception of boron and lithium. Concentrations of some trace metals in geothermal water may exceed drinking water standards by several orders of magnitude. Geothermal influences on water quality are likely to be localized, depending on directions of ground water flow, the relative volumes of geothermal sources and ground water originating from other sources, and depth below the surface from which water is withdrawn. It is important to understand the areal extent of shallow mixing of geothermal water because it may have adverse chemical and aesthetic effects on domestic drinking water. It would be useful to understand the areal extent of these effects.

  7. A new investigation on the water isotopes in the Badain Jaran Desert, China, for inferring water origination

    Science.gov (United States)

    Wu, X.; Wang, Y.; Wang, X. S.; Hu, B.

    2017-12-01

    Stable isotope δ2H, δ18O and d-excess values of water have previously been used to study the hydraulic connection of groundwater between the surrounding areas such as Heihe River Basin, Qilian Mountain and the Badain Jaran desert (BJD), China. We choose to focus on the effects of strong evaporation on the isotopic characteristics of water in the desert to better understand the origin of water in the BJD. A series of evaporation experiments were conducted in the desert to examine how it may change during evaporation and infiltration under local environmental conditions. Evaporation from open water was monitored in two experiments using local groundwater and lake water, respectively. And evaporation of soil water was observed in three pits which were excavated to different depths below a flat ground surface to install the evaporation-infiltration systems. Water samples were also collected from lakes, a spring and local unconfined aquifer for analyses of stable hydrogen and oxygen isotope ratios, and d-excess values in the BJD. The results show that water isotope contents became progressively enriched along an evaporation line, and the d-excess values decreased with the evaporation. The strong relationship of d-excess and δ18O values was observed from both the experiments and the water samples of groundwater and lakes, which is considered to be a signature of strong evaporation. Also, all the values of groundwater and lake water samples fall along with the evaporation line established through the evaporation experiments, indicating that lakes and groundwater in the study area have evolved from meteoric precipitation under modern or similar to modern climatic conditions. Analysis of a few previously published d-excess and δ18O values of groundwater from the BJD, Lake Eyre Basin, Australia, and Jabal Hafit mountain, United Arab Emirates reveals strong relationships between the two, suggesting similar recharge processes as observed in the BJD. This study demonstrated

  8. Effects of livestock watering sites on alien and native plants in the Mojave Desert, USA

    Science.gov (United States)

    Brooks, M.L.; Matchett, J.R.; Berry, K.H.

    2006-01-01

    Increased livestock densities near artificial watering sites create disturbance gradients called piospheres. We studied responses of alien and native annual plants and native perennial plants within 9 piospheres in the Mojave Desert of North America. Absolute and proportional cover of alien annual plants increased with proximity to watering sites, whereas cover and species richness of native annual plants decreased. Not all alien species responded the same, as the alien forb Erodium cicutarium and the alien grass Schismus spp. increased with proximity to watering sites, and the alien annual grass Bromus madritensis ssp. rubens decreased. Perennial plant cover and species richness also declined with proximity to watering sites, as did the structural diversity of perennial plant cover classes. Significant effects were focused within 200 m of the watering sites, suggesting that control efforts for alien annual plants and restoration efforts for native plants should optimally be focused within this central part of the piosphere gradient.

  9. Water osmotic absorption in Coleus blumei plants under salinity stress

    Directory of Open Access Journals (Sweden)

    José Ozinaldo Alves de Sena

    2006-11-01

    Full Text Available Three month old Coleus blumei plants in pots were treated with different NaCl concentrations: 0.00, 0.25, 0.50 and 1.00%. To determine the water osmotic absorption, the plants had their stems cut at 10 cm from the soil surface. The remaining stems were linked to glass tubes by flexible rubber tubes. Readings of the water column level in the glass tubes were performed at each 30 minutes, corresponding to the water osmotic absorption, with a total of eleven readings. Other Coleus blumei, with the same age, received the NaCl concentrations, and were evaluated under field conditions in terms of transpiration and stomatal resistance. A randomized complete block analysis was used with five replications. An increase of osmotic absorption was verified for all treatments up to three hours after application. Then a proportional reversion of osmotic absorption to the increases on saline concentration was observed, with a higher effect in the treatment with NaCl 1.00%, showing the increase of water loss by the roots. During this period time, the treatment showed a normal linear growth of the osmotic absorption. Transpiration was reduced proportionally to the increase of salinity concentration.Mudas envasadas de Coleus blumei, com três meses de idade, foram submetidas a diferentes concentrações de cloreto de sódio (NaCl: 0,00; 0,25; 0,50 e 1,00%. Visando determinar a absorção osmótica, as mudas tiveram seus caules cortados a 10 cm acima do solo. Os caules remanescentes foram interligados a tubos de vidro por tubos flexíveis de borracha. Foram feitas leituras (cm a cada 30 minutos dos níveis das colunas de água nos capilares, correspondentes às absorções osmóticas de água, sendo ao todo realizadas onze leituras. Em outro momento, mudas de C. blumei, com a mesma idade das anteriores, receberam as mesmas concentrações de NaCl descritas anteriormente, e, ao ar livre, foram avaliadas em termos de transpiração e resistência estomática, usando

  10. Effect of water salinity on wheat inoculated with N fixing bacteria using 15N tracer technique

    International Nuclear Information System (INIS)

    Al-Sayed, M. A.; Soliman, S. M.; Galal, Y. G. M.; El-Hadidi, E. M.

    2012-12-01

    A pot experiment was carried out under greenhouse controlled conditions to investigate the effect of water salinity and bacterial inoculation on growth parameters and nutrient uptake by wheat ( Triticum aestivum, L. seda 6). Dry matter yield of shoots was gradually increased with increasing water salinity levels under dual inoculation (Rh + Az). This phenomenon was more pronounced with 6 ds m -1 rather than 3 ds m -1 water salinity level. This holds true with all inoculation treatments. Similar trend was noticed with root dry matter yield. N uptake by shoots was positively affected by water salinity levels under bacterial inoculation especially the dual treatments where N uptake tended to increase with increasing water salinity levels. N uptake by roots was severely affected by increasing water salinity levels as compared to fresh water treatment. N uptake by shoots was enhanced by inoculation under different water salinity levels as compared to the un inoculated treatment. Nitrogen uptake roots was dramatically affected by inoculation. It was only increased by inoculation when plants were irrigated with fresh water. Portions of Ndff were frequently affected by both water salinity levels and microbial inoculation. wheat plant as representative of cereal crops was more dependent on the portion of nitrogen up taken from fertilizer rather than those fixed from the air. Therefore, the plant-bacteria association was not efficient enough. Inoculated treatments compensated considerable amounts of its N demand from air beside those derived from fertilizer, therefore the remained N from fertilizer in soil was higher than those of un inoculated control which is more dependable on Ndff as well as Ndf s. 1 5N recovery by wheat plants was enhanced by bacterial inoculation as well as water salinity levels did. (Author)

  11. Water Use Efficiency in Saline Soils under Cotton Cultivation in the Tarim River Basin

    Directory of Open Access Journals (Sweden)

    Xiaoning Zhao

    2015-06-01

    Full Text Available The Tarim River Basin, the largest area of Chinese cotton production, is receiving increased attention because of serious environmental problems. At two experimental stations (Korla and Aksu, we studied the influence of salinity on cotton yield. Soil chemical and physical properties, soil water content, soil total suction and matric suction, cotton yield and water use efficiency under plastic mulched drip irrigation in different saline soils was measured during cotton growth season. The salinity (mS·cm−1 were 17–25 (low at Aksu and Korla, 29–50 (middle at Aksu and 52–62 (high at Aksu for ECe (Electrical conductivity measured in saturation-paste extract of soil over the 100 cm soil profile. The soil water characteristic curves in different saline soils showed that the soil water content (15%–23% at top 40 cm soil, lower total suction power (below 3500 kPa and lower matric suction (below 30 kPa in low saline soil at Korla had the highest water use efficiency (10 kg·ha−1·mm−1 and highest irrigation water use efficiency (12 kg·ha−1·mm−1 and highest yield (6.64 t·ha−1. Higher water content below 30 cm in high saline soil increased the salinity risk and led to lower yield (2.39 t·ha−1. Compared to low saline soils at Aksu, the low saline soil at Korla saved 110 mm irrigation and 103 mm total water to reach 1 t·ha−1 yield and increased water use efficiency by 5 kg·ha−1·mm−1 and 7 kg·ha−1·mm−1 for water use efficiency (WUE and irrigation water use efficiency (IWUE respectively.

  12. Effects of deficit drip-irrigation scheduling regimes with saline water on pepper yield, water productivity and soil salinity under arid conditions of Tunisia

    Directory of Open Access Journals (Sweden)

    Kamel Nagaz

    2012-12-01

    Full Text Available A two-year study was carried out in order to assess the effects of different irrigation scheduling regimes with saline water on soil salinity, yield and water productivity of pepper under actual commercial-farming conditions in the arid region of Tunisia. Pepper was grown on a sandy soil and drip-irrigated with water having an ECi of 3.6 dS/m. Irrigation treatments consisted in water replacements of accumulated ETc at levels of 100% (FI, full irrigation, 80% (DI-80, 60% (DI-60, when the readily available water in the control treatment (FI is depleted, deficit irrigation during ripening stage (FI-MDI60 and farmer method corresponding to irrigation practices implemented by the local farmers (FM. Results on pepper yield and soil salinity are globally consistent between the two-year experiments and shows significant difference between irrigation regimes. Higher soil salinity was maintained over the two seasons, 2008 and 2009, with DI-60 and FM treatments than FI. FI-MDI60 and DI-80 treatments resulted also in low ECe values. Highest yields for both years were obtained under FI (22.3 and 24.4 t/ha although we didn’t find significant differences with the regulated deficit irrigation treatment (FI-DI60. However, the DI-80 and DI-60 treatments caused significant reductions in pepper yields through a reduction in fruits number/m² and average fruit weight in comparison with FI treatment. The FM increased soil salinity and caused significant reductions in yield with 14 to 43%, 12 to 39% more irrigation water use than FI, FI-MDI60 and DI-80 treatments, respectively, in 2008 and 2009. Yields for all irrigation treatments were higher in the second year compared to the first year. Water productivity (WP values reflected this difference and varied between 2.31 and 5.49 kg/m3. The WP was found to vary significantly among treatments, where the highest and the lowest values were observed for DI-60 treatment and FM, respectively. FI treatment provides

  13. Origin of salinity in produced waters from the Palm Valley gas field, Northern Territory, Australia

    International Nuclear Information System (INIS)

    Andrew, Anita S.; Whitford, David J.; Berry, Martin D.; Barclay, Stuart A.; Giblin, Angela M.

    2005-01-01

    The chemical composition and evolution of produced waters associated with gas production in the Palm Valley gas field, Northern Territory, has important implications for issues such as gas reserve calculations, reservoir management and saline water disposal. The occurrence of saline formation water in the Palm Valley field has been the subject of considerable debate. There were no occurrences of mobile water early in the development of the field and only after gas production had reduced the reservoir pressure, was saline formation water produced. Initially this was in small quantities but has increased dramatically with time, particularly after the initiation of compression in November 1996. The produced waters range from highly saline (up to 300,000 mg/L TDS), with unusual enrichments in Ca, Ba and Sr, to low salinity fluids that may represent condensate waters. The Sr isotopic compositions of the waters ( 87 Sr/ 86 Sr = 0.7041-0.7172) are also variable but do not correlate closely with major and trace element abundances. Although the extreme salinity suggests possible involvement of evaporite deposits lower in the stratigraphic sequence, the Sr isotopic composition of the high salinity waters suggests a more complex evolutionary history. The formation waters are chemically and isotopically heterogeneous and are not well mixed. The high salinity brines have Sr isotopic compositions and other geochemical characteristics more consistent with long-term residence within the reservoir rocks than with present-day derivation from a more distal pool of brines associated with evaporites. If the high salinity brines entered the reservoir during the Devonian uplift and were displaced by the reservoir gas into a stagnant pool, which has remained near the reservoir for the last 300-400 Ma, then the size of the brine pool is limited. At a minimum, it might be equivalent to the volume displaced by the reservoired gas

  14. Geomorphologic and geologic overview for water resources development: Kharit basin, Eastern Desert, Egypt

    Science.gov (United States)

    Mosaad, Sayed

    2017-10-01

    This study demonstrates the importance of geomorphologic, geologic and hydrogeologic assessment as an efficient approach for water resources development in the Kharit watershed. Kharit is one of largest watersheds in the Eastern Desert that lacks water for agricultural and drinking purposes, for the nomadic communities. This study aims to identify and evaluate the geomorphologic, geologic and hydrogeologic conditions in the Kharit watershed relative to water resource development using remote sensing and GIS techniques. The results reveal that the watershed contains 15 sub-basins and morphometric analyses show high probability for flash floods. These hazards can be managed by constructing earth dikes and masonry dams to minimize damage from flash floods and allow recharge of water to shallow groundwater aquifers. The Quaternary deposits and the Nubian sandstone have moderate to high infiltration rates and are relatively well drained, facilitating surface runoff and deep percolation into the underlying units. The sediments cover 54% of the watershed area and have high potential for groundwater extraction.

  15. Experimental Performance of Spatial Interpolators for Ground Water Salinity

    International Nuclear Information System (INIS)

    Alsaaran, Nasser A.

    2005-01-01

    Mapping groundwater qualities requires either sampling on a fine regular grid or spatial interpolation. The latter is usually used because the cost of the former is prohibitive. Experimental performance of five spatial interpolators for groundwater salinity was investigated using cross validation. The methods included ordinary kriging (OK), lognormal kriging, inverse distance, inverse squared distance and inverse cubed distance. The results show that OK outperformed other interpolators in terms of bias. Interpolation accuracy based on mean absolute difference criterion is relatively high for all interpolators with small difference among them. While three-dimensional surfaces produced by all inverse distance based procedures are dominated by isolated peaks and pits, surfaces produced by kriging are free from localized pits and peaks, and show areas of low groundwater salinity as elongated basins and areas of high salinity as ridges, which make regional trends easy to identify. Considering all criteria, OK was judged to be the most suitable spatial interpolator for groundwater salinity in this study. (author)

  16. Air-Surface-Ground Water Cycling in an Agricultural Desert Valley of Southern Colorado

    Science.gov (United States)

    Lanzoni, M.

    2017-12-01

    In dryland areas around the world, vegetation plays an important role in stabilizing soil and encouraging recharge. In the Colorado high desert of the San Luis Valley, windstorms strip away topsoil and deposit dust on the surrounding mountain snowpack. Dust-on-snow lowers albedo and hastens melting, which in turn lowers infiltration and aquifer recharge. Since the 1990s, the San Luis Valley has experienced a sharp decline in aquifer levels due to over-development of its water resources. Where agricultural abstraction is significant, the unconfined aquifer has experienced a 9 m (30 ft) drop. Over the course of three years, this dryland hydrology study analyzed rain, snow, surface and ground water across a 20,000 km2 high desert area to establish a baseline of water inputs. δ18O and δ2H were analyzed to develop a LMWL specific to this region of the southern Rockies and isotopic differences were examined in relation to chemistry to understand environmental influences on meteoric waters. This work identifies a repeating pattern of acid rainfall with trace element contaminants, including actinides.To better understand how the area's dominant vegetation responds to a lowered water table, 76 stem water samples were collected from the facultative phreatophyte shrubs E. nauseosa and S. vermiculatus over the summer, fall, spring, and summer of 2015 and 2016 from study plots chosen for increasing depths to groundwater. This research shows distinct patterns of water capture strategy and seasonal shifts among the E. nauseosa and S. vermiculatus shrubs. These differences are most apparent where groundwater is most accessible. However, where the water table has dropped 6 m (20 feet) over the last decade, both E. nauseosa and S. vermiculatus survive only on near-surface snowmelt and rain.

  17. IRRIGATION WITH SALINE WATER AND NITROGEN IN PRODUCTION COMPONENTS AND YIELD OF SUNFLOWER

    OpenAIRE

    JOÃO BATISTA DOS SANTOS; DOROTEU HONÓRIO GUEDES FILHO; HANS RAJ GHEYI; GEOVANI SOARES DE LIMA; LOURIVAL FERREIRA CAVALCANTE

    2016-01-01

    Due to the quantitative and qualitative limitation of water resources, saline water irrigation and nitrogen (N) fertilisation can contribute positively to the expansion of sunflower cultivation in the semiarid region of Northeast Brazil. Thus, this study aimed to evaluate production components and yield of sunflower, cv. „Embrapa 122 - V2000‟, irrigated with waters of different salinity levels (electrical conductivity – ECw) and fertilised with varying amounts of N in a field experiment ...

  18. Salinization of a fresh palaeo-ground water resource by enhanced recharge.

    Science.gov (United States)

    Leaney, F W; Herczeg, A L; Walker, G R

    2003-01-01

    Deterioration of fresh ground water resources caused by salinization is a growing issue in many arid and semi-arid parts of the world. We discuss here the incipient salinization of a 10(4) km2 area of fresh ground water (Australia caused by widespread changes in land use. Ground water 14C concentrations and unsaturated zone Cl soil water inventories indicate that the low salinity ground water originated mainly from palaeo-recharge during wet climatic periods more than 20,000 years ago. However, much of the soil water in the 20 to 60 m thick unsaturated zone throughout the area is generally saline (>15,000 mg/L) because of relatively high evapotranspiration during the predominantly semiarid climate of the last 20,000 years. Widespread clearing of native vegetation over the last 100 years and replacement with crops and pastures leads to enhancement of recharge rates that progressively displace the saline soil-water from the unsaturated zone into the ground water. To quantify the impact of this new hydrologic regime, a one-dimensional model that simulates projected ground water salinities as a function of depth to ground water, recharge rates, and soil water salt inventory was developed. Results from the model suggest that, in some areas, the ground water salinity within the top 10 m of the water table is likely to increase by a factor of 2 to 6 during the next 100 years. Ground water quality will therefore potentially degrade beyond the point of usefulness well before extraction of the ground water exhausts the resource.

  19. Surface energy balance of fresh and saline waters : AquaSEBS

    NARCIS (Netherlands)

    Abdelrady, A.R.; Timmermans, J.; Vekerdy, Z.; Salama, M.S.

    2016-01-01

    Current earth observation models do not take into account the influence of water salinity on the evaporation rate, even though the salinity influences the evaporation rate by affecting the density and latent heat of vaporization. In this paper, we adapt the SEBS (Surface Energy Balance System) model

  20. Formation and spreading of Arabian Sea high-salinity water mass

    Digital Repository Service at National Institute of Oceanography (India)

    PrasannaKumar, S.; Prasad, T.G.

    The formation and seasonal spreading of the Arabian Sea High-Salinity Water (ASHSW) mass were studied based on the monthly mean climatology of temperature and salinity in the Arabian Sea, north of the equator and west of 80 degrees E, on a 2 degrees...

  1. Effects of application timing of saline irrigation water on broccoli production and quality

    Science.gov (United States)

    Irrigation with moderately saline water is a necessity in many semi-arid areas of the Mediterranean Basin, and requires adequate irrigation management strategies. Broccoli (Brassica oleracea var. italica), a crop moderately tolerant to salinity stress, was used to evaluate the effects of the applica...

  2. Effect of salinity on growth, water use and nutrient use in radish (Raphanus sativus L.)

    NARCIS (Netherlands)

    Marcelis, L.F.M.; Hooijdonk, van J.

    1999-01-01

    Radish (Raphanus sativus L.) plants were grown at five soil salinity levels (1, 2, 4, 9 and 13 dS m-1) to analyse the effects on growth, dry matter partitioning, leaf expansion and water and nutrient use. Salinity was varied by proportionally changing the concentration of all macro nutrients. When

  3. Evaluation of available saline water resources in New Mexico for the production of microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Lansford, R.; Hernandez, J.; Enis, P.; Truby, D.; Mapel, C.

    1990-08-01

    Researchers evaluated saline water resources in New Mexico for their suitability as sites for large-scale microalgae production facilities. Production of microalgae could provide a renewable source of fuel, chemicals, and food. In addition, making use of the unused saline water resources would increase the economic activity in the state. After analyzing the 15 billion acre-ft of unused saline water resources in the state, scientists narrowed the locations down to six sites with the most potential. With further analysis, they chose the Tularosa Basin in southern New Mexico as the best-suited area for 100-hectare microalgae production facility. 34 refs., 38 figs., 14 tabs.

  4. Surface Energy Balance of Fresh and Saline Waters: AquaSEBS

    Directory of Open Access Journals (Sweden)

    Ahmed Abdelrady

    2016-07-01

    Full Text Available Current earth observation models do not take into account the influence of water salinity on the evaporation rate, even though the salinity influences the evaporation rate by affecting the density and latent heat of vaporization. In this paper, we adapt the SEBS (Surface Energy Balance System model for large water bodies and add the effect of water salinity to the evaporation rate. Firstly, SEBS is modified for fresh-water whereby new parameterizations of the water heat flux and sensible heat flux are suggested. This is achieved by adapting the roughness heights for momentum and heat transfer. Secondly, a salinity correction factor is integrated into the adapted model. Eddy covariance measurements over Lake IJsselmeer (The Netherlands are carried out and used to estimate the roughness heights for momentum (~0.0002 m and heat transfer (~0.0001 m. Application of these values over the Victoria and Tana lakes (freshwater in Africa showed that the calculated latent heat fluxes agree well with the measurements. The root mean-square of relative-errors (rRMSE is about 4.1% for Lake Victoria and 4.7%, for Lake Tana. Verification with ECMWF data showed that the salinity reduced the evaporation at varying levels by up to 27% in the Great Salt Lake and by 1% for open ocean. Our results show the importance of salinity to the evaporation rate and the suitability of the adapted-SEBS model (AquaSEBS for fresh and saline waters.

  5. Soil Salinity Controls on Water and Carbon Cycling by Sunflower Plants

    Science.gov (United States)

    Runkle, B.; Liang, X.; Dracup, J.; Hao, F.; Zeng, A.; Zhang, J.; He, B.; Oki, T.

    2007-12-01

    Agricultural effects on water cycling are of great importance for regional water resources management. These effects vary based on local soil and climate conditions, and are particularly modulated by high soil salinity levels, which stress plant growth and change their water use efficiency. Increasing salinization is predicted under hotter, drier conditions resulting from global climate change and from increased societal pressure on agricultural lands. This increased ionic presence creates a higher soil osmotic pressure that increases the resistance to water flow through the plant. This change also impacts the assimilation of carbon dioxide through the stomatal opening, and so affects rates of both photosynthesis and transpiration. Current agricultural and land-surface models that account for salinity do so in an overly empirical manner that cannot account for changes at different time scales in meteorological conditions. They tend to be ill equipped to examine how changing carbon dioxide levels may modify a plant's response to soil salinity. As a result, we present a new model of soil-vegetation- atmosphere water transfer that explicitly incorporates the role of soil salinity in changing this system's behavior. This model will allow for much greater flexibility in examining how vegetation may change the local water cycle under the joint impacts of both salinity and climate change. This model is supported by field research on the effects of salinity on sunflower plants in a large irrigation district in Inner Mongolia, China. Results presented include the role of salinity in changing stomatal regulation of water use efficiency, sub-canopy changes in leaf pressure, and changes in root activity. Modeling at sub-hourly time scales allows for a more precise understanding of how soil salinity changes the diurnal cycle of plant water use.

  6. Further investigations of aquaponics using brackish water resources of the Negev desert

    Directory of Open Access Journals (Sweden)

    Samuel Appelbaum

    2016-10-01

    Full Text Available Outdoor, floating raft aquaponic systems using the brackish waters of the Negev Desert in Israel and a fresh water control are described. 7 m2 of vegetables and herbs were grown in each recirculating system with Tilapia sp. fish. Plant growth was excellent for species such as celery, Swiss chard, spring onions and watercress, and fish health and growth were good. Growth rates for fish were, however, low, with an upper limit of 1.1 g per day and would have increased with ad libitum feeding. Water quality was well controlled, and iron chelate was added to correct chlorosis problems. Leafy growth was very good, but fruiting could be improved with the addition of potassium (K and other micronutrients.

  7. Response of CO and H2 uptake to extremes of water stress in saline and non-saline soils

    Science.gov (United States)

    King, G.

    2017-12-01

    Neither carbon monoxide (CO) nor hydrogen (H2) have direct impacts on radiative forcing, but both play important roles in tropospheric chemistry. Soils affect both the fate and significance of atmospheric CO and H2 by acting as strong global gas sinks ( 15% and >75 %, respectively), but much remains unknown about the microbiology of these gases, including responses to key environmental drivers. The role of water availability, measured as water potential, has been addressed to a limited extent by earlier studies with results suggesting that CO and H2 uptake are strongly limited by water stress. However recent results indicate a much greater tolerance of water stress than previously suspected. Ex situ assays have shown that non-saline playa soils from the Alvord Basin (Oregon, USA) consumed atmospheric and exogenous hydrogen and CO under conditions of severe water stress. CO uptake occurred at water potentials stress), indicating remarkable tolerance of desiccating conditions. Tolerance to water stress for CO and H2 uptake was also observed for soils from a montane rainforest (Hawai`i, USA). However, unlike playa soils rainforest soils seldom experience extended drought that would select for desiccation tolerance. While CO uptake by forest soils was more sensitive to water stress (limits -10MPa) than in playa soils, H2 uptake was observed at -90 MPa to -100 MPa. Tolerance at these levels might be due to the formation of intracellular water that limits the local effects of stress. Comparisons of water stress responses between saline and non-saline soils further suggested that communities of CO- and H2-oxidizing were generally robust with respect to stresses resulting from solute and matric effects. Collectively the results indicate that models of global CO and H2 dynamics might be improved by incorporating responses to soil water stress that could be estimated using relative humidity regimes calibrated for different soil types and systems. Incorporating water stress

  8. Feasibility study of brackish water desalination in the Egyptian deserts and rural regions using PV systems

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, G.E. [National Research Centre, Dokki, Cairo (Egypt). Solar Energy Dept.; Schmid, J. [Institute fuer Solare Energieversorgungstechnik, Kassel (Germany)

    2002-12-01

    Fresh water is the most important source for life on the earth. In the Egyptian deserts and rural areas, there is a shortage of fresh water in spite of the presence of large sources of brackish water. Solar energy is abundant in these remote areas of Egypt, where the amount of sunshine hours is around 3500 h/year. This paper introduces a feasibility study of water desalination in these areas using photovoltaic energy as the primary source of energy. The availability of water resources and solar energy in these areas has been investigated. Also, a design of a PV powered small scale reverse osmosis water desalination system is studied and economically estimated. It is found that the cost of producing 1 m{sup 3} of fresh water using the small PV powered RO water desalination systems is 3.73 dollars. This cost is based on using a small system that is operating during the daylight only. If the system size and the daily period of operation are increased, the price of producing fresh water will be decreased in these regions. Also, it is important to mention that using renewable energy sources in feeding different systems in these rural areas with their energy demands will maintain their environment clean and healthy for people. (author)

  9. Experimental studies of low salinity water flooding in carbonate reservoirs: A new promising approach

    DEFF Research Database (Denmark)

    Zahid, Adeel; Shapiro, Alexander; Skauge, Arne

    2012-01-01

    Low salinity water flooding is well studied for sandstone reservoirs, both laboratory and field tests have showed improvement in the oil recovery in many cases. Up to very recently, the low salinity effect has been indeterminated for carbonates. Most recently, Saudi Aramco reported that substantial...... reservoirs. In this paper, we have experimentally investigated the oil recovery potential of low salinity water flooding for carbonate rocks. We used both reservoir carbonate and outcrop chalk core plugs. The flooding experiments were carried out initially with the seawater, and afterwards additional oil...... both at ambient and high temperature. No low salinity effect was observed for the reservoir carbonate core plug at the ambient temperature, but increase of the pressure drop over the core plug was detected. On the contrary, a significant increase in oil recovery was observed under low salinity flooding...

  10. Base of moderately saline ground water in San Juan County, Utah

    International Nuclear Information System (INIS)

    Howells, L.

    1990-01-01

    The base of moderately saline groundwater was delineated for San Juan County, Utah, based on water-quality data and formation-water resistivity determined from geophysical well logs using the resistivity-porosity, spontaneous-potential, and resistivity-ratio methods. These data and the contour map developed from them show that a thick layer of very saline to briny groundwater underlies the eastern two-thirds of San Juan County. The upper surface of this layer is affected by the geologic structure of the area, is affected by the geologic structure of the area, but it may be modified locally by recharge mounds of less saline water and by vertical leakage of water through transmissive faults and fractures. The highest altitude of the base of moderately saline water is west of the Abajo Mountains where it is more than 6,500 ft above sea level. The lowest altitude is in the western part of the county and is below sea level; depressions in the base of moderately saline water in recharge areas in the La Sal and Abajo Mountains also may be that low. The base of moderately saline water commonly is in the Permian Cutler Formation or the Pennsylvanian Honaker Trail Formation of the Hermosa Group, but locally may be as high stratigraphically as the Triassic and Jurassic Navajo Sandstone north of the Abajo Mountains and in the Jurassic Morrison Formation south of the mountains

  11. Gulf of Maine - Water Salinity, Temperature and Sigma t (density) data from 1956 to 1980

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This table contains water salinity, temperature and sigma t (density) data from 1956 to 1980 binned at 10 meter depth intervals (from 300 meters up to 0 meters) for...

  12. Gulf of Maine - Water Salinity, Temperature and Sigma t (density) data from 1912 to 1930

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This table contains water salinity, temperature and sigma t (density) data from 1912 to 1930 binned at 10 meter depth intervals (from 300 meters up to 0 meters) for...

  13. Gulf of Maine - Water Salinity, Temperature and Sigma t (density) data from 1981 to 2005

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This table contains water salinity, temperature and sigma t (density) data from 1981 to 2005 binned at 10 meter depth intervals (from 300 meters up to 0 meters) for...

  14. Gulf of Maine - Water Salinity, Temperature and Sigma t (density) data from 1931 to 1955

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This table contains water salinity, temperature and sigma t (density) data from 1931 to 1955 binned at 10 meter depth intervals (from 300 meters up to 0 meters) for...

  15. Salinity and cationic nature of irrigation water on castor bean cultivation

    Directory of Open Access Journals (Sweden)

    Geovani S. de Lima

    Full Text Available ABSTRACT This study aimed to evaluate the water relations, cell damage percentage and growth of the castor bean cv. ‘BRS Energia’ as a function of salinity and cationic nature of the water used in irrigation. The experiment was conducted in drainage lysimeters under greenhouse conditions in eutrophic Grey Argisol of sandy loam texture. Six combinations of water salinity and cations were studied (S1 - Control; S2 - Na+, S3 - Ca2+, S4 - Na+ + Ca2+; S5 - K+ and S6 - Na+ + Ca2+ + Mg2+, in a randomized block design with four replicates. In the control (S1, plants were irrigated with 0.6 dS m-1 water, whereas the other treatments received 4.5 dS m-1 water, obtained by adding different salts, all in the chloride form. Higher relative water content in the leaf blade of plants irrigated with K+-salinized water associated with leaf succulence are indicative of tolerance of the castor bean cv. ‘BRS Energia’ to salinity. Saline stress negatively affected castor bean growth, regardless of cationic nature of water. Among the ions studied, ‘BRS Energia’ castor bean was more sensitive to the presence of sodium in the irrigation water, in terms of both water relations and leaf succulence.

  16. Effect of salinity and temperature on water cut determination in oil reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, Abdel-Mohsen O.; El Gamal, Maisa [Department of Civil and Environmental Engineering, College of Engineering, United Arab Emirates University, P.O. Box 17555, Al-Ain (United Arab Emirates); Zekri, Abdulrazag Y. [Department of Chemical and Petroleum Engineering, College of Engineering, United Arab Emirates University, P.O. Box 17555, Al-Ain (United Arab Emirates)

    2003-12-01

    In this study, system stability and water cut were evaluated via IR analysis and physicochemical properties of the tested mixture. Samples were prepared with different water cuts at a specified salinity and tested by IR. Different cations were also used in the water portion of the mixture to evaluate its effect of interaction and stability. In addition, the effect of water cut, temperature, salinity and cation type, and composition on specific gravity, API gravity, kinematic and dynamic viscosities and surface tension were investigated. The studied water content range was from 0 to 0.8 while temperature from 20 to 100 C. Salinity effect up to 40,000 ppm was also evaluated. For each mixed ion solution, equivalent sodium concentrations and mixture resistivity were calculated. Relationships between water cut, major functional groups and mixture physicochemical properties were developed. Therefore, for a known property, water cut could be predicted.

  17. Shielding of optical pulses on hydrodynamical time scales in laser-induced breakdown of saline water

    OpenAIRE

    Conti, Daniel; Marino, Francesco; Roati, Giacomo; Orfila, Alejandro; Javaloyes, Julien; Piro, Oreste; Balle, Salvador

    2014-01-01

    Pulse shielding in Laser-Induced Breakdown of saline water on hydrodynamic time scales is experimentally characterized. Pairs of pulses from a Nd:YAG laser are focused into saline water with a controlled time delay between them. The Laser-Induced Breakdown produced by the first pulse creates a cavitation bubble that later collapses generating a plume of bubbles that evolves on hydrodynamic time scales. When the second pulse arrives, the light is scattered by this plume with a consequent reduc...

  18. Plant aquaporins: new perspectives on water and nutrient uptake in saline environment.

    Science.gov (United States)

    del Martínez-Ballesta, M C; Silva, C; López-Berenguer, C; Cabañero, F J; Carvajal, M

    2006-09-01

    The mechanisms of salt stress and tolerance have been targets for genetic engineering, focusing on ion transport and compartmentation, synthesis of compatible solutes (osmolytes and osmoprotectants) and oxidative protection. In this review, we consider the integrated response to salinity with respect to water uptake, involving aquaporin functionality. Therefore, we have concentrated on how salinity can be alleviated, in part, if a perfect knowledge of water uptake and transport for each particular crop and set of conditions is available.

  19. Water sources accessed by arid zone riparian trees in highly saline environments, Australia.

    Science.gov (United States)

    Costelloe, Justin F; Payne, Emily; Woodrow, Ian E; Irvine, Elizabeth C; Western, Andrew W; Leaney, Fred W

    2008-05-01

    The flow regimes of arid zone rivers are often highly variable, and shallow groundwater in the alluvial aquifers can be very saline, thus constraining the availability and quality of the major water sources available to riparian trees-soil water, shallow groundwater and stream water. We have identified water sources and strategies used by riparian trees in more highly saline and arid conditions than previously studied for riparian trees of arid zone rivers. Our research focused on the riparian species Eucalyptus coolabah, one of the major riparian trees of ephemeral arid zone rivers in Australia. The water sources available to this riparian tree were examined using delta(18)O isotope data from xylem, soil water, groundwater and surface water. Additionally, soil chloride and matric potential data were used to infer zones of water availability for root uptake. Despite the saline conditions, the trees used a mixture of soil water and groundwater sources, but they did not use surface water directly. The study identified three strategies used to cope with typically high groundwater and soil water salinities. Firstly, the trees preferentially grow in zones of most frequent flushing by infiltrating streamflow, such as the bank-tops of channels. Secondly, the trees limit water use by having low transpiration rates. Thirdly, the trees are able to extract water at very low osmotic potentials, with water uptake continuing at chloride concentrations of at least 20,000-30,000 mg L(-1).

  20. Fluctuations of fresh-saline water interface and of water table induced by sea tides in unconfined aquifers

    Science.gov (United States)

    Levanon, Elad; Shalev, Eyal; Yechieli, Yoseph; Gvirtzman, Haim

    2016-10-01

    This study examines effects of tides on fluctuations of the fresh-saline water interface and the groundwater level in unconfined coastal aquifers using a two-dimensional numerical model. The time-lags of the simulated hydraulic heads and salinities fluctuations compared to sea level fluctuations are analyzed using cross-correlation analysis. The results show that both the fresh-saline water interface and the groundwater level are affected harmonically by sea tide fluctuations. However, significantly different time-lags are obtained between the hydraulic head in the deeper and upper parts of the aquifer, and between head and salinity in the fresh-saline water interface. The hydraulic head in the deeper part of the aquifer responses much faster to sea level fluctuations than in the upper part. Surprisingly, a similar difference is detected between the time-lag of the hydraulic head in the fresh-saline water interface and the time-lag of the salinity at the same location. Furthermore, the time-lag of the salinity in the fresh-saline water interface is similar to the time-lag of the water table. We suggest a comprehensive mechanism for tidal influence on the coastal groundwater system, in which two main processes act simultaneously. First, sea tide causes a pressure head wave which propagates into the saturated zone of the aquifer, governed by the diffusivity of the aquifer (Ks/Ss). Second, this pressure head wave is attenuated at the water table due to the unsaturated flow within the capillary fringe which occurs during groundwater level oscillations. Because the tidal forcing acts on the sea-floor boundary and the attenuation of the groundwater level due to capillary effect acts on the groundwater table, two dimensional distributions of time-lag and hydraulic head amplitude are created. The capillary effect in the unsaturated zone plays a key role not only in the water table fluctuations as shown previously, but also on the salinity fluctuations in the fresh-saline

  1. Salinity guidelines for irrigation: Case studies from Water Research ...

    African Journals Online (AJOL)

    the management of soils under irrigation. The results from long-term irrigation case studies along the Lower Vaal River and Breede River show that the quality of soils can be improved. The opposite is also true where mismanagement occurred. Research on the salinity threshold of major crops (grapevines, wheat, maize, ...

  2. The structural modification of cassava starch using a saline water pretreatment

    Directory of Open Access Journals (Sweden)

    Hanny Frans SANGIAN

    2018-04-01

    Full Text Available Abstract The cassava has been modified successfully by using the saline water, which was abundantly available on the planet. The biomass was submerged in saline waters that salt concentrations were altered at 0, 3.5 percent (seawater and 10 percent (w/w and were kept 5 days. After recovery by washing steps, the treated solids were characterized by using XRD (X-ray diffraction , FTIR (Fourier transform infra-red, and SEM (Scanning electron microscopic. The results showed that the XRD pattern of saline water pretreatment decreased significantly. The biggest decrease of X-ray intensity occurred at around 18o. Meanwhile, the fingerprint of FTIR revealed the transmittance intensity of infra-red ray of saline water treated solid inclined for all wave constant numbers, suggesting that many hydrogen bonds were disconnected. Those findings also were enhanced by SEM pictures that showed the change of surface morphology of treated biomass. It was indicative that cassava structure was modified becoming more textured after employing saline water pretreatment. This work is an innovative finding to gradually substitute commercial ionic liquids that are very expensive with saline water for biomass pretreatment.

  3. Quantifying saline groundwater seepage to surface waters in the Athabasca oil sands region

    International Nuclear Information System (INIS)

    Jasechko, Scott; Gibson, John J.; Jean Birks, S.; Yi, Yi

    2012-01-01

    Western Canadian oil sands contain over 170 billion barrels of proven unconventional petroleum reserves currently extracted at 1.8 million barrels per day by either surface mining, or by in situ techniques that require subsurface injection of steam and hydrocarbon solvents. Natural high-salinity springs are known to add water and entrained inorganic and organic constituents to the Athabasca River and its tributaries in the region of ongoing bitumen production. However, the magnitude and synoptic distribution of these saline inputs has remained unquantified. Here, a chloride mass balance is used to estimate saline groundwater discharge to the Athabasca River from 1987 to 2010. Results show that the highest saline water discharge rate to the Athabasca River occurs between Ft. McMurray and the Peace-Athabasca Delta, supported by subcrop exposure of lower Cretaceous- and Devonian-aged formations bearing saline waters. Further, the input of saline groundwater is found to be an important control on the chemistry of the lower Athabasca River, despite comprising 10 −1 to 3% of the Athabasca River’s discharge. The flux of natural saline groundwater entering the Athabasca does not appear to have increased or decreased from 1987 to 2010. The origin of seep salinity is interpreted as relict subglacial meltwater that has dissolved Devonian-aged evaporites, supported by saline Na-Cl type waters with low 18 O/ 16 O and 2 H/ 1 H ratios relative to modern precipitation. The magnitude of groundwater discharge and its impact on the Athabasca River’s chemistry in the area of ongoing bitumen development warrants the incorporation of natural groundwater seepages into surface water quality monitoring networks.

  4. The effects of salinity in the soil water balance: A Budyko's approach

    Science.gov (United States)

    Perri, S.; Viola, F.; Molini, A.

    2017-12-01

    Soil degradation and water scarcity pose important constraints on productivity and development of arid and semi-arid countries. Among the main causes of loss of soil fertility, aridification and soil salinization are deeply connected threats enhanced by climate change. Assessing water availability is fundamental for a large number of applications especially in arid regions. An approach often adopted to estimate the long-term rainfall partitioning into evapotranspiration and runoff is the Budyko's curve. However, the classical Budyko framework might not be able to properly reproduce the water balance in salt affected basins, especially under elevated soil salinization conditions. Salinity is a limiting factor for plant transpiration (as well as growth) affecting both short and long term soil moisture dynamics and ultimately the hydrologic balance. Soluble salts cause a reduction of soil water potential similar to the one arising from droughts, although plant adaptations to soil salinity show extremely different traits and can vary from species to species. In a similar context, the salt-tolerance plants are expected to control the amount of soil moisture lost to transpiration in saline soils, also because salinity reduces evaporation. We propose a simple framework to include the effects of salinization on the surface energy and water balance within a simple Budyko approach. By introducing the effects of salinity in the stochastic water balance we are able to include the influence of vegetation type (i.e. in terms of salt-tolerance) on evapotranspiration-runoff partitioning under different climatic conditions. The water balance components are thus compared to data obtained from arid salt-affected regions.

  5. Multifactorial control of water and saline intake: role of a2-adrenoceptors

    Directory of Open Access Journals (Sweden)

    L.A. De-Luca Jr.

    1997-04-01

    Full Text Available Water and saline intake is controlled by several mechanisms activated during dehydration. Some mechanisms, such as the production of angiotensin II and unloading of cardiovascular receptors, activate both behaviors, while others, such as the increase in blood osmolality or sodium concentration, activate water, but inhibit saline intake. Aldosterone probably activates only saline intake. Clonidine, an a2-adrenergic agonist, inhibits water and saline intake induced by these mechanisms. One model to describe the interactions between these multiple mechanisms is a wire-block diagram, where the brain circuit that controls each intake is represented by a summing point of its respective inhibiting and activating factors. The a2-adrenoceptors constitute an inhibitory factor common to both summing points

  6. Kinetic model for predicting the concentrations of active halogen species in chlorinated saline cooling waters

    International Nuclear Information System (INIS)

    Lietzke, M.H.; Haag, W.R.

    1979-01-01

    A kinetic model for predicting the composition of chlorinated water discharged from power plants using fresh water for cooling was previously reported. The model has now been extended to be applicable to power plants located on estuaries or on the seacoast where saline water is used for cooling purposes. When chloride is added to seawater to prevent biofouling in cooling systems, bromine is liberated. Since this reaction proceeds at a finite rate there is a competition between the bromine (i.e., hypobromous acid) and the added chlorine (i.e., hypochlorous acid) for halogenation of any amine species present in the water. Hence not only chloramines but also bromamines and bromochloramines will be formed, with the relative concentrations a function of the pH, temperature, and salinity of the water. The kinetic model takes into account the chemical reactions leading to the formation and disappearance of the more important halamines and hypohalous acids likely to be encountered in chlorinated saline water

  7. Salinity of irrigation water in the Philippi farming area of the Cape ...

    African Journals Online (AJOL)

    2012-03-01

    Mar 1, 2012 ... This paper explores the nature, source and spatial variation of the salinity of water used for irrigation in a coastal urban farming area in Cape Town, South Africa, where water from the Cape Flats aquifer is drawn into storage ponds and used for crop irrigation. Water samples were collected in summer and ...

  8. Provision of Desalinated Irrigation Water by the Desalination of Groundwater within a Saline Aquifer

    Directory of Open Access Journals (Sweden)

    David D. J. Antia

    2016-12-01

    Full Text Available Irrigated land accounts for 70% of global water usage and 30% of global agricultural production. Forty percent of this water is derived from groundwater. Approximately 20%–30% of the groundwater sources are saline and 20%–50% of global irrigation water is salinized. Salinization reduces crop yields and the number of crop varieties which can be grown on an arable holding. Structured ZVI (zero valent iron, Fe0 pellets desalinate water by storing the removed ions as halite (NaCl within their porosity. This allows an “Aquifer Treatment Zone” to be created within an aquifer, (penetrated by a number of wells (containing ZVI pellets. This zone is used to supply partially desalinated water directly from a saline aquifer. A modeled reconfigured aquifer producing a continuous flow (e.g., 20 m3/day, 7300 m3/a of partially desalinated irrigation water is used to illustrate the impact of porosity, permeability, aquifer heterogeneity, abstraction rate, Aquifer Treatment Zone size, aquifer thickness, optional reinjection, leakage and flow by-pass on the product water salinity. This desalination approach has no operating costs (other than abstraction costs (and ZVI regeneration and may potentially be able to deliver a continuous flow of partially desalinated water (30%–80% NaCl reduction for $0.05–0.5/m3.

  9. Salinity impacts on water solubility and n-octanol/water partition coefficients of selected pesticides and oil constituents.

    Science.gov (United States)

    Saranjampour, Parichehr; Vebrosky, Emily N; Armbrust, Kevin L

    2017-09-01

    Salinity has been reported to influence the water solubility of organic chemicals entering marine ecosystems. However, limited data are available on salinity impacts for chemicals potentially entering seawater. Impacts on water solubility would correspondingly impact chemical sorption as well as overall bioavailability and exposure estimates used in the regulatory assessment. The pesticides atrazine, fipronil, bifenthrin, and cypermethrin, as well as the crude oil constituent dibenzothiophene together with 3 of its alkyl derivatives, all have different polarities and were selected as model compounds to demonstrate the impact of salinity on their solubility and partitioning behavior. The n-octanol/water partition coefficient (K OW ) was measured in both distilled-deionized water and artificial seawater (3.2%). All compounds had diminished solubility and increased K OW values in artificial seawater compared with distilled-deionized water. A linear correlation curve estimated salinity may increase the log K OW value by 2.6%/1 log unit increase in distilled water (R 2  = 0.97). Salinity appears to generally decrease the water solubility and increase the partitioning potential. Environmental fate estimates based on these parameters indicate elevated chemical sorption to sediment, overall bioavailability, and toxicity in artificial seawater. These dramatic differences suggest that salinity should be taken into account when exposure estimates are made for marine organisms. Environ Toxicol Chem 2017;36:2274-2280. © 2017 SETAC. © 2017 SETAC.

  10. Mediterranean sea water budget long-term trend inferred from salinity observations

    Science.gov (United States)

    Skliris, N.; Zika, J. D.; Herold, L.; Josey, S. A.; Marsh, R.

    2018-01-01

    Changes in the Mediterranean water cycle since 1950 are investigated using salinity and reanalysis based air-sea freshwater flux datasets. Salinity observations indicate a strong basin-scale multi-decadal salinification, particularly in the intermediate and deep layers. Evaporation, precipitation and river runoff variations are all shown to contribute to a very strong increase in net evaporation of order 20-30%. While large temporal uncertainties and discrepancies are found between E-P multi-decadal trend patterns in the reanalysis datasets, a more robust and spatially coherent structure of multi-decadal change is obtained for the salinity field. Salinity change implies an increase in net evaporation of 8 to 12% over 1950-2010, which is considerably lower than that suggested by air-sea freshwater flux products, but still largely exceeding estimates of global water cycle amplification. A new method based on water mass transformation theory is used to link changes in net evaporation over the Mediterranean Sea with changes in the volumetric distribution of salinity. The water mass transformation distribution in salinity coordinates suggests that the Mediterranean basin salinification is driven by changes in the regional water cycle rather than changes in salt transports at the straits.

  11. Contribution of water chemistry and fish condition to otolith chemistry: comparisons across salinity environments.

    Science.gov (United States)

    Izzo, C; Doubleday, Z A; Schultz, A G; Woodcock, S H; Gillanders, B M

    2015-06-01

    This study quantified the per cent contribution of water chemistry to otolith chemistry using enriched stable isotopes of strontium ((86) Sr) and barium ((137) Ba). Euryhaline barramundi Lates calcarifer, were reared in marine (salinity 40), estuarine (salinity 20) and freshwater (salinity 0) under different temperature treatments. To calculate the contribution of water to Sr and Ba in otoliths, enriched isotopes in the tank water and otoliths were quantified and fitted to isotope mixing models. Fulton's K and RNA:DNA were also measured to explore the influence of fish condition on sources of element uptake. Water was the predominant source of otolith Sr (between 65 and 99%) and Ba (between 64 and 89%) in all treatments, but contributions varied with temperature (for Ba), or interactively with temperature and salinity (for Sr). Fish condition indices were affected independently by the experimental rearing conditions, as RNA:DNA differed significantly among salinity treatments and Fulton's K was significantly different between temperature treatments. Regression analyses did not detect relations between fish condition and per cent contribution values. General linear models indicated that contributions from water chemistry to otolith chemistry were primarily influenced by temperature and secondly by fish condition, with a relatively minor influence of salinity. These results further the understanding of factors that affect otolith element uptake, highlighting the necessity to consider the influence of environment and fish condition when interpreting otolith element data to reconstruct the environmental histories of fish. © 2015 The Fisheries Society of the British Isles.

  12. Fog-basking behaviour and water collection efficiency in Namib Desert Darkling beetles

    Directory of Open Access Journals (Sweden)

    Dacke Marie

    2010-07-01

    Full Text Available Abstract Background In the Namib Desert fog represents an alternative water source. This is utilised by Darkling beetles (Tenebrionidae that employ different strategies for obtaining the fog water. Some dig trenches in the sand, while others use their own bodies as fog collectors assuming a characteristic fog-basking stance. Two beetle species from the genus Onymacris have been observed to fog-bask on the ridges of the sand dunes. These beetles all have smooth elytra surfaces, while another species with elytra covered in bumps is reported to have specialised adaptations facilitating water capture by fog-basking. To resolve if these other beetles also fog-bask, and if an elytra covered in bumps is a more efficient fog water collector than a smooth one, we examined four Namib Desert beetles; the smooth Onymacris unguicularis and O. laeviceps and the bumpy Stenocara gracilipes and Physasterna cribripes. Here we describe the beetles' fog-basking behaviour, the details of their elytra structures, and determine how efficient their dorsal surface areas are at harvesting water from fog. Results The beetles differ greatly in size. The largest P. cribripes has a dorsal surface area that is 1.39, 1.56, and 2.52 times larger than O. unguicularis, O. laeviceps, and S. gracilipes, respectively. In accordance with earlier reports, we found that the second largest O. unguicularis is the only one of the four beetles that assumes the head standing fog-basking behaviour, and that fog is necessary to trigger this behaviour. No differences were seen in the absolute amounts of fog water collected on the dorsal surface areas of the different beetles. However, data corrected according to the sizes of the beetles revealed differences. The better fog water harvesters were S. gracilipes and O. unguicularis while the large P. cribripes was the poorest. Examination of the elytra microstructures showed clear structural differences, but the elytra of all beetles were found to

  13. Fog-basking behaviour and water collection efficiency in Namib Desert Darkling beetles.

    Science.gov (United States)

    Nørgaard, Thomas; Dacke, Marie

    2010-07-16

    In the Namib Desert fog represents an alternative water source. This is utilised by Darkling beetles (Tenebrionidae) that employ different strategies for obtaining the fog water. Some dig trenches in the sand, while others use their own bodies as fog collectors assuming a characteristic fog-basking stance. Two beetle species from the genus Onymacris have been observed to fog-bask on the ridges of the sand dunes. These beetles all have smooth elytra surfaces, while another species with elytra covered in bumps is reported to have specialised adaptations facilitating water capture by fog-basking. To resolve if these other beetles also fog-bask, and if an elytra covered in bumps is a more efficient fog water collector than a smooth one, we examined four Namib Desert beetles; the smooth Onymacris unguicularis and O. laeviceps and the bumpy Stenocara gracilipes and Physasterna cribripes. Here we describe the beetles' fog-basking behaviour, the details of their elytra structures, and determine how efficient their dorsal surface areas are at harvesting water from fog. The beetles differ greatly in size. The largest P. cribripes has a dorsal surface area that is 1.39, 1.56, and 2.52 times larger than O. unguicularis, O. laeviceps, and S. gracilipes, respectively. In accordance with earlier reports, we found that the second largest O. unguicularis is the only one of the four beetles that assumes the head standing fog-basking behaviour, and that fog is necessary to trigger this behaviour. No differences were seen in the absolute amounts of fog water collected on the dorsal surface areas of the different beetles. However, data corrected according to the sizes of the beetles revealed differences. The better fog water harvesters were S. gracilipes and O. unguicularis while the large P. cribripes was the poorest. Examination of the elytra microstructures showed clear structural differences, but the elytra of all beetles were found to be completely hydrophobic. The differences in

  14. Final Technical Report: Effects of Changing Water and Nitrogen Inputs on a Mojave Desert Ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Stanley, D.; Nowak, Robert S.; Fenstermaker, Lynn, F.; Young, Michael,H.

    2007-11-30

    In order to anticipate the effects of global change on ecosystem function, it is essential that predictive relationships be established linking ecosystem function to global change scenarios. The Mojave Desert is of considerable interest with respect to global change. It contains the driest habitats in North America, and thus most closely approximates the world’s great arid deserts. In order to examine the effects of climate and land use changes, in 2001 we established a long-term manipulative global change experiment, called the Mojave Global Change Facility. Manipulations in this study include the potential effects of (1) increased summer rainfall (75 mm over three discrete 25 mm events), (2) increased nitrogen deposition (10 and 40 kg ha-1), and (3) the disturbance of biological N-fixing crusts . Questions addressed under this grant shared the common hypothesis that plant and ecosystem performance will positively respond to the augmentation of the most limiting resources to plant growth in the Mojave Desert, e.g., water and nitrogen. Specific hypotheses include (1) increased summer rainfall will significantly increase plant production through an alleviation of moisture stress in the dry summer months, (2) N-deposition will increase plant production in this N-limited system, particularly in wet years or in concert with added summer rain, and (3) biological crust disturbance will gradually decrease bio-available N, with concomitant long-term reductions in photosynthesis and ANPP. Individual plant and ecosystem responses to global change may be regulated by biogeochemical processes and natural weather variability, and changes in plant and ecosystem processes may occur rapidly, may occur only after a time lag, or may not occur at all. During the first PER grant period, we observed changes in plant and ecosystem processes that would fall under each of these time-response intervals: plant and ecosystem processes responded rapidly to added summer rain, whereas most

  15. Radiolarian artificial neural network based paleo sea surface water temperature and salinity changes during the last glacial cycle in the Timor Sea, Indian Ocean

    Science.gov (United States)

    Gupta, S. M.; Malmgren, B. A.

    2015-12-01

    The western Pacific water enters into the Timor Sea (tropical Indian Ocean) by the thermohaline conveyor belt, and this region is under the influence of the SW monsoon. The higher precipitation during the monsoon rains lower the surface salinity in the north-eastern Indian Ocean towards the Bay of Bengal; whereas, the Arabian Sea remains highly saline due to higher evaporation in the region surrounding Arabian deserts. The salinity contrast in the northern Indian Ocean is very unique, and the radiolarian micro-zooplanktons living in the surface water serve a very good proxy for the monsoonal changes in the surface sea-water temperature (SST) and salinity in the geological past. We studied radiolarian faunal variation in the core MD01-2378, located at ~13oS and ~121oE (1783 m water depth), at the inlet of the thermohaline circulation into the Timor Sea. We applied the modern radiolarian based artificial neural networks (ANNs) (Gupta and Malmgren, 2009) to derive the SST and salinity during August-October for the last 140 ka (the full last glacial cycle). Based on the mean estimates of the 10 ANNs, the root mean square error in prediction (RMSEP) for SST is ~1.4oC with correlation between observed and estimated values r=0.98 (Gupta and Malmgren, 2009). Similarly, the RMSEP is 0.3 psu (r=0.94) for the salinity estimates. We derived paleo-SSTs and salinity values using modern radiolarian ANNs and the fossil radiolarian data generated from the core for the last 140-ka (Fig.1). The age model of the core is based on δ18O benthic oxygen isotope stratigraphy and 21 AMS 14C ages up to ~30-ka (Holbourn et al., 2005). Paleo SST-summer varied between 22-28.5oC, and it is in very good agreement with the δ18O benthic record of Holbourn et al. (2005) defining the Last Glacial Maximum (~24 ka) and the Eemian (~125 ka) stages. The salinity fluctuated between 34-35 psu, and compared well with oxygen isotope record representing the LGM and Eemian periods. We gratefully acknowledge

  16. Dryland salinity: threatening water resources in the semi-arid Western Cape

    CSIR Research Space (South Africa)

    Bugan, Richard DH

    2010-11-01

    Full Text Available in the soil and vadose zone of a 16 hectare small scale catchment, exhibiting evidence of dryland salinity and representative of semi-arid conditions in the Berg River catchment. At this site, salt sources and storage were studied and also groundwater...: THREATENING WATER RESOURCES IN THE SEMI-ARID WESTERN CAPE Increased dryland salinity in the Swartland and Overberg regions poses a threat to the bread basket of the Western Cape, water resources in an already water-stressed area, water supply...

  17. Nutrient and water addition effects on day- and night-time conductance and transpiration in a C3 desert annual

    NARCIS (Netherlands)

    Ludwig, F.; Jewitt, R.A.; Donovan, L.A.

    2006-01-01

    Recent research has shown that many C3 plant species have significant stomatal opening and transpire water at night even in desert habitats. Day-time stomatal regulation is expected to maximize carbon gain and prevent runaway cavitation, but little is known about the effect of soil resource

  18. Desert water harvesting from TAKYR surfaces: assessing the potential of traditional and experimental technologies in the karakum

    NARCIS (Netherlands)

    Fleskens, L.; Ataev, A.; Mamedov, B.; Spaan, W.P.

    2007-01-01

    From historical times the traditionally nomadic people in desert environments of Turkmenistan have applied a range of innovative technologies to secure water supply for consumptive and productive purposes. These technologies make use of takyrs, flat or slightly sloping dense clay surfaces which act

  19. Experimental study on water transport observations of desert riparian forests in the lower reaches of the Tarim River in China.

    Science.gov (United States)

    Chen, Yaning; Li, Weihong; Zhou, Honghua; Chen, Yapeng; XinmingHao; Fu, Aihong; Ma, Jianxin

    2017-06-01

    Studying the water use processes of desert riparian vegetation in arid regions and analyzing the response and adaptation strategies of plants to drought stress are of great significance for developing ecological restoration measures. Based on field monitoring and test analyses of physiological ecological indicators of dominant species (Populus euphratica and Tamarix chinensis) in the desert riparian forest in the lower reaches of the Tarim River, the water relations of P. euphratica and T. chinensis under drought stress are discussed and some water use strategies put forward. The results show that (1) concerning plant water uptake, desert riparian forests depend mainly on groundwater to survive under long-term water stress. (2) Concerning plant water distribution, the survival of P. euphratica and nearby shallow root plants is mainly due to the hydraulic lift and water redistribution of P. euphratica under drought stress. (3) Concerning plant water transport, P. euphratica sustains the survival of competitive and advantageous branches by improving their ability to acquire water while restraining the growth of inferior branches. (4) Concerning plant transpiration, the sap flow curves of daily variations of P. euphratica and T. chinensis were wide-peak sin and narrower-peak respectively. T. chinensis has better environmental adaptability.

  20. Algal massive growth in relation to water quality and salinity at Damietta, north of Egypt

    Directory of Open Access Journals (Sweden)

    Mohamed Ali Ibraheem Deyab

    2015-02-01

    Full Text Available Objective: To relate the proliferation and dominance of certain algal species at the Damietta and its relation to water quality. Methods: Water and algal biomass were bimonthly sampled from five selected sites at Damietta Province, Egypt during 2012. Algae were identified and quantified. Waters, algae and sediment were analyzed. Results: The physicochemical properties of water showed limited seasonal but substantial local variation. The high levels of nitrogen and phosphorus and turbidity of water pointed to marked eutrophication, which could enhance massive algal growth. The temporal fluctuation in temperature, exposure to industrial and domestic sewage and salinity results in succession between blooming algal species. Spirulina platensis and Chlorella vulgaris alternated in a moderately saline water and Oscillatoria agardhii and Mougeotia scalaris in a fresh water body during summer and winter respectively. Likewise, Microcystis aureginosa and Ulva lactuca alternated in a moderately saline site during autumn and summer respectively. Cladophora albida dominated a fish pond of brackish water and Dunaliella salina dominated the most saline water over the whole period of study. Conclusions: Growth of the predominant algal species is correlated to water quality. These species are of considerable nutritive value, with moderate contents of protein, carbohydrate, macronutrients and micronutrients, which evaluates them for usage as food (green and macroalgae, fodder or bio-fertilizer (cyanophytes.

  1. Ecohydrological feedbacks between soil salinity and vegetation dynamics as mediated by interactions with the water table

    Science.gov (United States)

    Runyan, C.; D'Odorico, P.

    2010-12-01

    In areas with relatively shallow water tables, changes in vegetation cover may affect local hydrologic conditions and favor the accumulation of salt within different parts of the soil profile. Because most plants are sensitive to saline soil water, a salt-vegetation feedback may exist, whereby vegetation cover maintains deeper water tables and slower rates of salt accumulation. As a result of this feedback, both a state with vegetation cover, deep water table, and low salinity, and a state with sparse or no vegetation, shallow water table and high salinity can be stable. Such dynamics may be present in the Murray Darling Basin, Australia, where widespread conversion from sclerophyll woodlands and forests to agricultural use has resulted in a decrease in the water table depth that has mobilized salts accumulated in the vadose zone and strongly increased the rate at which salts are transported within the system. To investigate these dynamics, we present a model to relate vegetation-soil salinity feedbacks - mediated by hydrologic conditions - to the emergence of multiple stable states in the underlying dynamics and apply this model to the Murray Darling Basin. Results for this case study show the presence of a strong feedback resulting in bistable dynamics for a wide range of environmental conditions (i.e., a range of precipitation regimes, soil textures, and salinities of irrigation and groundwater). This bistability increases the susceptibility of these systems to abrupt, highly irreversible shifts to stable bare soil, saline conditions and has important economic implications for dryland agricultural regimes worldwide as the presence of a shallow, saline water table is known to require costly remediation measures.

  2. A Numerical Modeling Study on Desert Oasis Self-Supporting Mechanisms

    Science.gov (United States)

    2005-01-01

    soil, and biological resources have led to drought, salinization, and desertification and conse- quently have hindered the development of sustainable...water vapor flux is downward over the Gobi desert (Wang and Mitsuta, 1992). As part of HEIFE, the fundamental observational period observations were...NW–SE) by 25 km (NE–SW), and is surrounded by sandy and Gobi deserts. Small sensible heat-flux and dominating latent heat-flux in the surface energy

  3. An improved film evaporation correlation for saline water at sub-atmospheric pressures

    KAUST Repository

    Shahzada, Muhammad Wakil

    2011-10-03

    This paper presents an investigation of heat transfer correlation in a falling-film evaporator working with saline water at sub-atmospheric pressures. The experiments are conducted at different salinity levels ranging from 15000 to 90000 ppm, and the pressures were maintained between 0.92 to 2.81 kPa (corresponds to saturation temperatures of 5.9 – 23 0C). The effect of salinity, saturation pressures and chilled water temperatures on the heat transfer coefficient are accounted in the modified film evaporation correlations. The results are fitted to the Han & Fletcher\\'s and Chun & Seban\\'s falling-film correlations which are used in desalination industry. We modify the said correlations by adding salinity and saturation temperature corrections with respective indices to give a better agreement to our measured data.

  4. Water relations and transpiration of quinoa (Chenopodium quinoa Willd.) under salinity and soil drying

    DEFF Research Database (Denmark)

    Razzaghi, Fatemeh; Ahmadi, Seyed Hamid; Adolf, Verena Isabelle

    2011-01-01

    Drought and salinity are the two major factors limiting crop growth and production in arid and semi-arid regions. The separate and combined effects of salinity and progressive drought in quinoa (Chenopodium quinoa Willd.) were studied in a greenhouse experiment. Stomatal conductance (gs), leaf...... values in both FI and PD. During the drought period, the xylem [ABA] extracted from the shoots increased faster than that extracted from the roots. A reduction in WT, caused by salinity and soil drying, reduced transpiration and increased apparent root resistance (R) to water uptake, especially in PD0.......42 or lower, but under the saline conditions of PD10 and PD20, the threshold values of RAW were 0.67 and 0.96, respectively. In conclusion, due to the additive effect of osmotic and matric potential during soil drying on soil water availability, quinoa should be re-irrigated at higher RAW in salt...

  5. Soil-water salinity pollution: extent, management and potential impacts on agricultural sustain ability

    International Nuclear Information System (INIS)

    Javid, M.A.; Ali, K.; Javed, M.; Mahmood, A.

    1999-01-01

    One of the significant environmental hazards of irrigated agriculture is the accumulation of salts in the soil. The presence of large quantities of certain soluble salts badly affects the physical, chemical, biological and fertility characteristics of the soils. This pollution of soil salinity and its toxic degradation directly affects plants, hence impacting the air filters of nature. The soil and water salinity has adversely reduced the yield of our major agricultural crops to an extent that agricultural sustainability is being threatened. Salinity has also dwindled the survival of marine life, livestock, in addition to damaging of construction works. The problem can be estimated from the fact that out of 16.2 m.ha of irrigated land of Pakistan, 6.3 . ha are salt affected in the Indus Plain. The state of water pollution can further be assessed from the fact that presently about 106 MAF of water is diverted from the rivers into the canals of the Indus Plain which contains 28 MT of salts. Due to soil and water pollution more than 40,000 ha of good irrigated land goes out of cultivation every year. This it has drastically reduced the potential of our agricultural lands. Hence, an estimated annual loss of Rs. 14,000 million has been reported due to this soil-water salinity pollution in Pakistan. Some management options to mitigate the soil - water salinity pollution are proposed. (author)

  6. Chickpea (Cicer arietinum L.) physiological, chemical and growth responses to irrigation with saline water

    DEFF Research Database (Denmark)

    Hirich, Abdelaziz; Omari, Halima El; Jacobsen, Sven-Erik

    2014-01-01

    water salinity has negatively affected growth and biomass accumulation and led to reduced grain yield, water uptake and water productivity. In contrast, proline, soluble sugars, Na+ and Na+: K+ ratio increased with increasing irrigation water salinity. The findings highlighted the role of proline...... was carried out on pot experiments. Differences in water uptake and plant growth; as well as proline, soluble sugar, and Na+ and K+ contents of the plant were quantified. The results showed a negative relationship between increasing water salinity and most of the measured plant growth parameters. Irrigation...... and soluble sugars as osmolytes produced by chickpea to mitigate the effect of salinity stress. The added value of these results is that the crop's responses to salinity are quantified. The obtained values can be used to determine 'threshold values'; should the salinity of the irrigation water go above...

  7. Hydrogeologic setting and hydrologic data of the Smoke Creek Desert basin, Washoe County, Nevada, and Lassen County, California, water years 1988-90

    Science.gov (United States)

    Maurer, D.K.

    1993-01-01

    Smoke Creek Desert is a potential source of water for urban development in Washoe County, Nevada. Hydrogeologic data were collected from 1988 to 1990 to learn more about surface- and ground-water flow in the basin. Impermeable rocks form a boundary to ground-water flow on the east side of the basin and at unknown depths at the base of the flow system. Permeable volcanic rocks on the west and north sides of the basin represent a previously unrecognized aquifer and provide potential avenues for interbasin flow. Geophysical data indicate that basin-fill sediments are about 2,000 feet thick near the center of the basin. The geometry of the aquifers, however, remains largely unknown. Measurements of water levels, pressure head, flow rate, water temperature, and specific conductance at 19 wells show little change from 1988 to 1990. Chemically, ground water begins as a dilute sodium and calcium bicarbonate water in the mountain blocks, changes to a slightly saline sodium bicarbonate solution beneath the alluvial fans, and becomes a briny sodium chloride water near the playa. Concentrations of several inorganic constituents in the briny water near the playa commonly exceed Nevada drinking-water standards. Ground water in the Honey Lake basin and Smoke Creek Desert basin has similar stable-isotope composition, except near Sand Pass. If interbasin flow takes place, it likely occurs at depths greater than 400-600 feet beneath Sand Pass or through volcanic rocks to the north of Sand Pass. Measure- ments of streamflow indicate that about 2,800 acre-feet/year discharged from volcanic rocks to streamflow and a minimum of 7.300 acre-feet/year infiltrated and recharged unconsolidated sediments near Smoke, Buffalo, and Squaw Creeks during the period of study. Also about 1,500 acre-feet per year was lost to evapotranspiration along the channel of Smoke Creek, and about 1,680 acre-feet per year of runoff from Smoke, Buffalo, and Squaw Creeks was probably lost to evaporation from the

  8. Irrigation with potable water versus normal saline in a contaminated musculoskeletal wound model.

    Science.gov (United States)

    Svoboda, Steven J; Owens, Brett D; Gooden, Heather A; Melvin, Michael L; Baer, David G; Wenke, Joseph C

    2008-05-01

    Although the use of potable water for wound irrigation is attractive in an austere environment, its effectiveness has not been tested. We sought to compare the effectiveness of potable water irrigation in reducing bacterial number with that of normal saline irrigation. We used an established caprine model involving the creation of a reproducible complex musculoskeletal wound followed by inoculation with luminescent bacteria that allowed for quantitative analysis with a photon-counting camera system. Six hours after injury and inoculation, wound irrigations were performed using pulsatile lavage. Fourteen goats were randomized into two treatment groups: irrigation with 9 L potable water versus irrigation with 9 L normal saline. Images obtained after irrigation were compared with baseline images to determine the reduction in bacterial luminescence resulting from treatment. The irrigation in both groups reduced the bacterial counts by 71% from the preirrigation levels. Potable water reduced the bacterial load as effectively as normal saline in our model.

  9. Transport of Astyanax altiparanae Garutti and Britski, 2000 in saline water

    Directory of Open Access Journals (Sweden)

    Ana Lúcia Salaro

    2015-08-01

    Full Text Available Two experiments were performed. The first aimed to assess the tolerance of fingerlings Astyanax altiparanae to water salinity. Fish were exposed to salinity of 0, 3, 6, 9, 12 or 15 g NaCl L-1 for 96 hours. The fish mortality was 0%, in the levels of 0, 3 and 6 g L-1; 75% in the level of 9 g L-1and 100% at 12 and 15 g L-1 of common salt. The second experiment aimed to assess the parameters of water quality, mortality and blood glucose during transport. For this, A. altiparanae were stored in plastic bags at 22, 30 and 37 g of fish L-1 stocking densities and salinity of 0, 3, 6 and 9 g L-1, for. Fish showed similar mortality levels in the different salinities and stocking densities. The increase in fish density reduced the dissolved oxygen levels and salinity decreased the pH. The blood glucose levels were higher in those fish with 0 g L-1 salinity and higher stocking densities. The addition of salt to the water reduces the stress responses of A. altiparanae during transport.

  10. The effect of water salinity on wood breakdown in semiarid Mediterranean streams.

    Science.gov (United States)

    Gómez, Rosa; Asencio, Antonia Dolores; Picón, José María; Del Campo, Rubén; Arce, María Isabel; Del Mar Sánchez-Montoya, María; Suárez, María Luisa; Vidal-Abarca, María Rosario

    2016-01-15

    Saline streams occur naturally and they are distributed worldwide, particularly in arid and semiarid regions, but human activities have also increased their number in many parts of the world. Little attention has been paid to assess increasing salt effects on organic matter decomposition. The objectives of this study were to analyse wood breakdown rates and how salinity affects them in 14 streams that exemplify a natural salinity gradient. We also analysed the effect of this gradient on changes in wood chemical composition, fungal biomass and microbial activity. Our results showed low breakdown rates (0.0010-0.0032 d(-1)), but they fell within the same range as those reported in freshwater streams when a similar woody substrate was used. However, salinity had a negative effect on the breakdown rates and fungal biomass along the salinity gradient, and led to noticeable changes in wood composition. Water salinity did not affect microbial activity estimated using hydrolysis of fluorescein diacetate. Variation in breakdown rates and fungal biomass across streams was mediated mainly by salinity, and later by stream discharge. Despite the role of fungi in stick breakdown, the potential wood abrasion by salts must be analysed in detail to accurately understand the effect of increasing salinity on organic matter breakdown. Finally, our results indicate that increased salinity worldwide by human activities or by the global warming would imply organic matter breakdown and mineralisation slowing down, even in natural saline streams. However, because many variables are implicated, the final effect of climatic change on organic matter decomposition in streams is difficult to predict. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Water and power for the desert -- Energy solutions for the Near and Middle East

    Energy Technology Data Exchange (ETDEWEB)

    Siersdorfer, D.

    2007-07-01

    2007 will mark a unique milestone in human history: for the first time ever, more people on earth will live and work in cities than in rural areas. Moreover, only four of the twenty biggest megacities with populations over 10 million will be in industrial nations; the others will be in threshold and developing countries. Accelerating urbanization and economic growth will fuel a massive demand for adequate infrastructures - such as power and water supplies. Reliable and economical supply of power and water to populations in regions of harsh environments, e.g. in the Near and Middle East, ensures basic survival rather than merely providing for a pleasant life. Economical supply of power and water for desert regions requires a wide mix of reliable technologies already available today and new technologies under development for future needs. Siemens Power Generation's Energy Solution Division, having proven its responsiveness in the past by playing a vital role in the development of the Near and Middle East, will continue to provide answers in future for meeting power and water demand within the regionally specific environment. (auth)

  12. Soil salinity and water productivity of carrot-millet system as influenced by irrigation regimes with saline water in arid regions of Tunisia

    Directory of Open Access Journals (Sweden)

    Fathia - El Mokh

    2013-12-01

    Full Text Available Field studies were conducted for three years to determine the effects of irrigation regimes with saline water (3.6 dS/m on soil salinity, yield and water productivity of carrot and millet under actual commercial-farming conditions in the arid region of Tunisia. Carrot and millet were grown during fall-winter and summer seasons on a sandy soil and surface and drip-irrigated with well water having an ECi of 3.6 dS/m. For three years, a complete randomized block design with four replicates was used to evaluate five irrigation regimes. Irrigation regimes consisted in water replacements of cumulated ETc at levels of 100% (SWB100, full irrigation, 80% (DI-80, 60% (DI-60, when the readily available water in SWB100 treatment is depleted, deficit irrigation during ripening stage (SWB100-DI60 and farmer method corresponding to irrigation practices implemented by the local farmers. The results showed that soil salinity was significantly affected by irrigation treatments. Higher soil salinity was maintained in the root zone with DI-60 and farmer irrigation treatments than full irrigation (SWB100. SWB100-DI60 and DI-80 treatments resulted also in low ECe values. Soil salinity was kept within acceptable limits for the growth of the crops grown in the rotation when SWB100, SWB100-DI60 and DI-80 strategies were employed. The rainfalls received during fall-winter and spring periods were effective in leaching salts from the soil profile. During the three year period, carrot and millet yield was highest for the SWB100 full treatment, (29.5, 28.7 and 26.8 t/ha for carrot and 27.2, 28.3 and 26.9 q/ha for millet although no significant differences were observed with the regulated deficit irrigation treatment (SWB100-DI60. However, the DI-80 and DI-60 deficit irrigation treatments caused significant reductions in carrot and millet yields through a reduction in roots number and weight, panicle number, kernel number and weight in comparison with SWB100. The farmer

  13. Contrasting water use pattern of introduced and native plants in an alpine desert ecosystem, Northeast Qinghai–Tibet Plateau, China

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Huawu, E-mail: wuhuawu416@163.com [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875 (China); College of Resources Science and Technology, Beijing Normal University, Beijing 100875 (China); Li, Xiao-Yan, E-mail: xyli@bnu.edu.cn [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875 (China); College of Resources Science and Technology, Beijing Normal University, Beijing 100875 (China); Jiang, Zhiyun; Chen, Huiying; Zhang, Cicheng; Xiao, Xiong [College of Resources Science and Technology, Beijing Normal University, Beijing 100875 (China)

    2016-01-15

    Plant water use patterns reflect the complex interactions between different functional types and environmental conditions in water-limited ecosystems. However, the mechanisms underlying the water use patterns of plants in the alpine desert of the Qinghai–Tibet Plateau remain poorly understood. This study investigated seasonal variations in the water sources of herbs (Carex moorcroftii, Astragalus adsurgens) and shrubs (Artemisia oxycephala, Hippophae rhamnoides) using stable oxygen-18 isotope methods. The results indicated that the native herbs (C. moorcroftii, A. adsurgens) and one of the shrubs (A. oxycephala) mainly relied on water from the shallow layer (0–30 cm) throughout the growing season, while the introduced shrub (H. rhamnoides) showed plasticity in switching between water from shallow and deep soil layers depending on soil water availability. All studied plants primarily depended on water from shallow soil layers early in the season. The differences of water use patterns between the introduced and native plants are closely linked with the range of active root zones when competing for water. Our findings will facilitate the mechanistic understanding of plant–soil–water relations in alpine desert ecosystems and provide information for screening introduced species for sand fixation. - Highlights: • Stable oxygen-18 in soil water experienced great evaporation enrichment. • H. rhamnoides experiences a flexible plasticity to switch between shallow and deep soil water. • Native plants mostly relied on shallow and middle soil water. • Water-use patterns by introduced-native plants are controlled by root characteristics.

  14. Evidence for high salinity of Early Cretaceous sea water from the Chesapeake Bay crater.

    Science.gov (United States)

    Sanford, Ward E; Doughten, Michael W; Coplen, Tyler B; Hunt, Andrew G; Bullen, Thomas D

    2013-11-14

    High-salinity groundwater more than 1,000 metres deep in the Atlantic coastal plain of the USA has been documented in several locations, most recently within the 35-million-year-old Chesapeake Bay impact crater. Suggestions for the origin of increased salinity in the crater have included evaporite dissolution, osmosis and evaporation from heating associated with the bolide impact. Here we present chemical, isotopic and physical evidence that together indicate that groundwater in the Chesapeake crater is remnant Early Cretaceous North Atlantic (ECNA) sea water. We find that the sea water is probably 100-145 million years old and that it has an average salinity of about 70 per mil, which is twice that of modern sea water and consistent with the nearly closed ECNA basin. Previous evidence for temperature and salinity levels of ancient oceans have been estimated indirectly from geochemical, isotopic and palaeontological analyses of solid materials in deep sediment cores. In contrast, our study identifies ancient sea water in situ and provides a direct estimate of its age and salinity. Moreover, we suggest that it is likely that remnants of ECNA sea water persist in deep sediments at many locations along the Atlantic margin.

  15. Prediction of Long-Term Drainage-Water Salinity of Pipe Drains

    NARCIS (Netherlands)

    Kelleners, T.J.; Kamra, S.K.; Jhorar, R.K.

    2000-01-01

    Long term drainage water salinity of pipe drains is modeled with the advection-dispersion equation for the zone above drain level and stream functions for the zone below drain level. Steady-state water flow is assumed. The model is applied to two experimental pipe drainage sites in Haryana State,

  16. Salinity of irrigation water in the Philippi farming area of the Cape ...

    African Journals Online (AJOL)

    Isotope analysis was done for the summer samples so as to assess effects of evaporation on water quality and salinity. Descriptive statistics were used to compare the variation in range of concentration of specific ions with the recommended ranges set by the South African Department of Water Affairs and Forestry (DWAF) ...

  17. Impact of saline water on soil properties and crop yield: a simulation study

    NARCIS (Netherlands)

    Tedeschi, A.; Barbieri, G.; Menenti, M.

    1996-01-01

    A field experiment on vegetable crops was carried out between 1988 and 1993 near Naples (Italy). The effect of saline water on soil properties was assessed by means of laboratory experiments on undisturbed soil cores. Significant differences in the soil water retention curves and unsaturated

  18. Soil Salt Distribution and Tomato Response to Saline Water Irrigation under Straw Mulching

    Science.gov (United States)

    Zhai, Yaming; Yang, Qian; Wu, Yunyu

    2016-01-01

    To investigate better saline water irrigation scheme for tomatoes that scheduling with the compromise among yield (Yt), quality, irrigation water use efficiency (IWUE) and soil salt residual, an experiment with three irrigation quotas and three salinities of irrigation water was conducted under straw mulching in northern China. The irrigation quota levels were 280 mm (W1), 320 mm (W2) and 360 mm (W3), and the salinity levels were 1.0 dS/m (F), 3.0 dS/m (S1) and 5.0 dS/m (S2). Compared to freshwater, saline water irrigations decreased the maximum leaf area index (LAIm) of tomatoes, and the LAIm presented a decline tendency with higher salinity and lower irrigation quota. The best overall quality of tomato was obtained by S2W1, with the comprehensive quality index of 3.61. A higher salinity and lower irrigation quota resulted in a decrease of individual fruit weight and an increase of the blossom-end rot incidence, finally led to a reduction in the tomato Yt and marketable yield (Ym). After one growth season of tomato, the mass fraction of soil salt in plough layer under S2W1 treatment was the highest, and which presented a decline trend with an increasing irrigation quota. Moreover, compared to W1, soil salts had a tendency to move to the deeper soil layer when using W2 and W3 irrigation quota. According to the calculation results of projection pursuit model, S1W3 was the optimal treatment that possessed the best comprehensive benefit (tomato overall quality, Yt, Ym, IWUE and soil salt residual), and was recommended as the saline water irrigation scheme for tomatoes in northern China. PMID:27806098

  19. Soil Salt Distribution and Tomato Response to Saline Water Irrigation under Straw Mulching.

    Science.gov (United States)

    Zhai, Yaming; Yang, Qian; Wu, Yunyu

    2016-01-01

    To investigate better saline water irrigation scheme for tomatoes that scheduling with the compromise among yield (Yt), quality, irrigation water use efficiency (IWUE) and soil salt residual, an experiment with three irrigation quotas and three salinities of irrigation water was conducted under straw mulching in northern China. The irrigation quota levels were 280 mm (W1), 320 mm (W2) and 360 mm (W3), and the salinity levels were 1.0 dS/m (F), 3.0 dS/m (S1) and 5.0 dS/m (S2). Compared to freshwater, saline water irrigations decreased the maximum leaf area index (LAIm) of tomatoes, and the LAIm presented a decline tendency with higher salinity and lower irrigation quota. The best overall quality of tomato was obtained by S2W1, with the comprehensive quality index of 3.61. A higher salinity and lower irrigation quota resulted in a decrease of individual fruit weight and an increase of the blossom-end rot incidence, finally led to a reduction in the tomato Yt and marketable yield (Ym). After one growth season of tomato, the mass fraction of soil salt in plough layer under S2W1 treatment was the highest, and which presented a decline trend with an increasing irrigation quota. Moreover, compared to W1, soil salts had a tendency to move to the deeper soil layer when using W2 and W3 irrigation quota. According to the calculation results of projection pursuit model, S1W3 was the optimal treatment that possessed the best comprehensive benefit (tomato overall quality, Yt, Ym, IWUE and soil salt residual), and was recommended as the saline water irrigation scheme for tomatoes in northern China.

  20. Interaction effects of water salinity and hydroponic growth medium on eggplant yield, water-use efficiency, and evapotranspiration

    Directory of Open Access Journals (Sweden)

    Farnoosh Mahjoor

    2016-06-01

    Full Text Available Eggplant (Solanum melongena L. is a plant native to tropical regions of Southeast Asia. The water crisis and drought on the one hand and eggplant greenhouse crop development as one of the most popular fruit vegetables for people on the other hand, led to the need for more research on the use of saline water and water stress to optimize salinity level and their impact on eggplant evapotranspiration and encounter better yield and crop quality. The objective of the present study was to investigate the interactions of water salinity and hydroponic growth medium on qualitative and quantitative properties of eggplant and its water-use efficiency. The study used the factorial experiment based on completely randomized design with three replications of four levels of water salinity (electrical conductivity of 0.8 (control, 2.5, 5, and 7 dS m−1 and three growth media (cocopeat, perlite, and a 50–50 mixture of the two by volume. Total yield, yield components, evapotranspiration, and water-use efficiency were determined during two growing periods, one each in 2012 and 2013. All of these indices decreased significantly as water salinity increased. Water with of 0.8 dS m−1 produced an average eggplant yield of 2510 g per plant in 2012 and 2600 g in 2013. The highest yield was observed in cocopeat. Water with 7 dS m−1 reduced yield to 906 g per plant in 2012 and to 960 g in 2013. Lowest yield was observed in perlite. The highest evapotranspiration values occurred in cocopeat at the lowest salinity in both years. Cocopeat and the cocopeat–perlite mixture were equally good substrates. The mixture significantly improved the quantitative and qualitative properties of eggplant yield.

  1. Growth of the damselfly Ischnura heterosticta is better in saline water than freshwater

    International Nuclear Information System (INIS)

    Kefford, Ben J.; Zalizniak, Liliana; Nugegoda, Dayanthi

    2006-01-01

    Increasing salinity has the potential to affect freshwater organisms. Yet sub-lethal effects of salinity on macroinvertebrates are poorly understood. Growth and development of Ischnura heterosticta (Odonata: Coenagrionidae) was experimentally shown to be faster in 5-20 mS/cm than 0.1-1 mS/cm, while in 35 mS/cm all individuals died. In 30 mS/cm about half died and growth was similar to the 0.1 mS/cm treatment. The salinity-growth relationship cannot be explained indirectly, that is salinity affecting the survival of their prey. Tissue content and concentration of Ca, Mg, Na and K in emerged adults showed no evidence of deficiencies at low salinity. Heart beat rate was similar across treatments, except at 35 mS/cm, where it was slower. Respiration and feeding were similar at 0.1, 10 and 30 mS/cm. While there are similarities in I. heterosticta and other species' salinity response, there are differences and studies on more species are urgently needed. - This species while typically found in freshwaters does better in saline waters

  2. Water supplementation affects the behavioral and physiological ecology of Gila monsters (Heloderma suspectum) in the Sonoran Desert.

    Science.gov (United States)

    Davis, Jon R; DeNardo, Dale F

    2009-01-01

    In desert species, seasonal peaks in animal activity often correspond with times of higher rainfall. However, the underlying reason for such seasonality can be hard to discern because the rainy season is often associated with shifts in temperature as well as water and food availability. We used a combination of the natural climate pattern of the Sonoran Desert and periodic water supplementation to determine the extent to which water intake influenced both the behavioral ecology and the physiological ecology of a long-lived desert lizard, the Gila monster (Heloderma suspectum) (Cope 1869). Water-supplemented lizards had lower plasma osmolality (i.e., were more hydrated) and maintained urinary bladder water reserves better during seasonal drought than did control lizards. During seasonal drought, water-supplemented lizards were surface active a significantly greater proportion of time than were controls. This increased surface activity can lead to greater food acquisition for supplemental Gila monsters because tail volume (an index of caudal lipid stores) was significantly greater in supplemented lizards compared with controls in one of the two study years.

  3. Water Scarcity, Food Insecurity and Drought Induced Displacement in an Arid Ecosystem: A Case Study in Indian Desert

    Science.gov (United States)

    Rehman Siddiqui, Azizur

    2017-04-01

    Indian Arid Ecosystem is characterised by scare as well as seasonal precipitation that have led to long term stress in a fragile ecosystem. In addition to this, over the years, Indian desert has experienced varying magnitude of drought, which have considerably influenced food and fodder production and led to the depletion of surface and ground water table. All these factors mean that the production potential of land is hardly sufficient to feed human as well as livestock population of the desert and this has led to extensive rural to urban migration in Indian Desert. In the present study, satellite data from Landsat TM, AWiFS, NOAA AVHRR have been used to detect the intensity and severity of drought condition, and data collected through primary survey has been used to measure the impact of water scarcity on food insecurity and drought induced migration. Rainfall trend analysis of the study area has been done with the help of Man Kendall Method to assess the meteorological vulnerability. In addition to these, NDVI, VCI, TCI, and VHI have also been used to find out the long term vegetation health in the study area. With the help of these scientific techniques, the paper focuses on the moisture deficiency during growing period and its effect on human population and livestock population. Keywords: Arid Ecosystem, Indian Desert, Drought, Migration

  4. [Effects of different irrigations on the water physiological characteristics of Haloxylon ammodendron in Taklimakan Desert hinterland].

    Science.gov (United States)

    Xie, Ting-ting; Zhang, Xi-ming; Liang, Shao-min; Shan, Li-shan; Yang, Xiao-lin; Hua, Yong-hui

    2008-04-01

    By using heat-balance stem flow gauge and press chamber, the water physiological characteristics of Haloxylon ammodendron under different irrigations in Taklimakan Desert hinterland were measured and analyzed. The results indicated that the diurnal variation curve of H. ammodendron stem sap flow varied with irrigations. When irrigated 35 and 24.5 kg x plant(-1) once time, the diurnal variation of stem sap flow changed in single peak curve and the variation extent was higher; while irrigated 14 kg x plant(-1) once time, the diurnal variation changed in two-peak curve and the variation extent was small. With the decrease of irrigations, the average daily sap flow rate and the daily water consumption of H. ammodendron decreased gradually, the dawn and postmeridian water potential also had a gradual decrease, and the correlations of stem sap flow with total radiation, air temperature, relative humidity, and wind speed enhanced. Under different irrigations, the correlation between stem sap flow rate and total radiation was always the best.

  5. Yield of cherry tomatoes as a function of water salinity and irrigation frequency

    Directory of Open Access Journals (Sweden)

    Alexandre N. Santos

    2016-02-01

    Full Text Available ABSTRACT The use of brackish water in agriculture can cause salinization of soils and reduce plant yield. This problem can be minimized by hydroponic cultivation, which improves plant development. The aim of this study was to evaluate the yield of cherry tomatoes grown in hydroponic system with substrate under salinity levels of the nutrient solution (NS, exposure time to salinity and irrigation frequency. The experiment was conducted in a greenhouse, in a randomized complete block design, in a 6 x 2 x 2 factorial scheme with five replicates: six salinity levels of NS prepared with brackish water (3.01; 4.51; 5.94; 7.34; 8.71 and 10.40 dS m-1; two exposure times to NS (60 and 105 days and two irrigation frequencies (one irrigation per day and irrigation every two days. Yield and production components of cherry tomatoes cv. 'Rita' were evaluated. NS salinity affected plant yield, reducing fruit production, which was more significant when plants were subjected to a longer time of exposure to salinity. There was no difference between NS applications on fruit production, when these applications were performed once a day or once every two days.

  6. Effects of salinity and water temperature on the ecological performance of Zostera marina

    DEFF Research Database (Denmark)

    Nejrup, Lars Brammer; Pedersen, Morten Foldager

    2008-01-01

    We tested the effects of salinity and water temperature on the ecological performance of eelgrass (Zostera marina L.) in culture-experiments to identify levels that could potentially limit survival and growth and, thus, the spatial distribution of eelgrass in temperate estuaries. The experiments...... for eelgrass appeared to lie between 10 and 20 8C. These results show that extreme conditions may affect the fitness of eelgrass and, thus, may potentially limit its distribution in coastal and estuarine waters....... included eight levels of salinity (2.5, 5, 10, 15, 20, 25, 30 and 35%) and seven water temperatures (5, 10, 15, 20, 25, 27.5 and 30 8C). Low salinity (i.e. 5 and 2.5%) increased mortality (3-6-fold) and had a strong negative effect on shoot morphology (number of leaves per shoot reduced by 40% and shoot...

  7. Landscape scale assessment of soil and water salinization processes in agricultural coastal area.

    Science.gov (United States)

    Elen Bless, Aplena; Follain, Stéphane; Coiln, François; Crabit, Armand

    2017-04-01

    Soil salinization is among main land degradation process around the globe. It reduces soil quality, disturbs soil function, and has harmful impacts on plant growth that would threaten agricultural sustainability, particularly in coastal areas where mostly susceptible on land degradation because of pressure from anthropogenic activities and at the same time need to preserve soil quality for supporting food production. In this presentation, we present a landscape scale analysis aiming to assess salinization process affecting wine production. This study was carried out at Serignan estuary delta in South of France (Languadoc Roussillon Region, 43˚ 28'N and 3˚ 31'E). It is a sedimentary basin near coastline of Mediterranean Sea. Field survey was design to characterize both space and time variability of soil and water salinity through water electrical conductivity (ECw) and soil 1/5 electrical conductivity (EC1/5). For water measurements, Orb River and groundwater salinity (piezometers) were determined and for soil 1737 samples were randomly collected from different soil depths (20, 50, 80, and 120 cm) between year 2012 and 2016 and measured. In order to connect with agricultural practices observations and interviews with farmers were conducted. We found that some areas combining specific criteria presents higher electrical conductivity: positions with lower elevation (a.s.l), Cambisols (Calcaric) / Fluvisols soil type (WRB) and dominated clay textures. These observations combined with geochemical determination and spatial analysis confirm our first hypothesis of sea salt intrusion as the main driven factor of soil salinity in this region. In this context, identification of salinization process, fine determination of pedological specificities and fine understanding of agricultural practices allowed us to proposed adaptation strategies to restore soil production function. Please fill in your abstract text. Key Words: Salinity, Coastal Agriculture, Landscape, Soil, Water

  8. Impact of saline water sources on hypertension and cardiovascular disease risk in coastal Bangladesh

    Science.gov (United States)

    Butler, Adrian; Hoque, Mohammad; Mathewson, Eleanor; Ahmed, Kazi; Rahman, Moshuir; Vineis, Paolo; Scheelbeek, Pauline

    2016-04-01

    Southern Bangladesh is periodically affected by tropical cyclone induced storm surges. Such events can result in the inundation of large areas of the coastal plain by sea water. Over time these episodic influxes of saline water have led to the build-up of a high of salinities (e.g. > 1,000 mg/l) in the shallow (up to ca. 150 m depth) groundwater. Owing to the highly saline groundwater, local communities have developed alternative surface water sources by constructing artificial drinking water ponds, which collect monsoonal rainwater. These have far greater storage than traditional rainwater harvesting systems, which typically use 40 litre storage containers that are quickly depleted during the dry season. Unfortunately, the ponds can also become salinised during storm surge events, the impacts of which can last for a number of years. A combined hydrological and epidemiological research programme over the past two years has been undertaken to understand the potential health risks associated with these saline water sources, as excessive intake of sodium can lead to hypertension and an increased risk of cardiovascular disease (such as stroke and heart attack). An important aspect of the selected research sites was the variety of drinking water sources available. These included the presence of managed aquifer recharge sites where monsoonal rainwater is stored in near-surface (semi-)confined aquifers for abstraction during the dry season. This provided an opportunity for the effects of interventions with lower salinity sources to be assessed. Adjusting for confounding factors such as age, gender and diet, the results show a significant association between salinity and blood pressure. Furthermore, the results also showed such impacts are reversible. In order to evaluate the costs and benefits of such interventions, a water salinity - dose impact model is being developed to assess the effectiveness of alternative drinking water sources, such as enhanced rainwater

  9. Geochemical processes controlling water salinization in an irrigated basin in Spain: Identification of natural and anthropogenic influence

    Energy Technology Data Exchange (ETDEWEB)

    Merchán, D., E-mail: d.merchan@igme.es [Geological Survey of Spain — IGME, C/Manuel Lasala 44 9B, 50006 Zaragoza (Spain); Auqué, L.F.; Acero, P.; Gimeno, M.J. [University of Zaragoza — Department of Earth Sciences (Geochemical Modelling Group), C/Pedro Cerbuna 12, 50009 Zaragoza (Spain); Causapé, J. [Geological Survey of Spain — IGME, C/Manuel Lasala 44 9B, 50006 Zaragoza (Spain)

    2015-01-01

    Salinization of water bodies represents a significant risk in water systems. The salinization of waters in a small irrigated hydrological basin is studied herein through an integrated hydrogeochemical study including multivariate statistical analyses and geochemical modeling. The study zone has two well differentiated geologic materials: (i) Quaternary sediments of low salinity and high permeability and (ii) Tertiary sediments of high salinity and very low permeability. In this work, soil samples were collected and leaching experiments conducted on them in the laboratory. In addition, water samples were collected from precipitation, irrigation, groundwater, spring and surface waters. The waters show an increase in salinity from precipitation and irrigation water to ground- and, finally, surface water. The enrichment in salinity is related to the dissolution of soluble mineral present mainly in the Tertiary materials. Cation exchange, precipitation of calcite and, probably, incongruent dissolution of dolomite, have been inferred from the hydrochemical data set. Multivariate statistical analysis provided information about the structure of the data, differentiating the group of surface waters from the groundwaters and the salinization from the nitrate pollution processes. The available information was included in geochemical models in which hypothesis of consistency and thermodynamic feasibility were checked. The assessment of the collected information pointed to a natural control on salinization processes in the Lerma Basin with minimal influence of anthropogenic factors. - Highlights: • Salinization in Lerma Basin was controlled by the dissolution of soluble salts. • Water salinization and nitrate pollution were found to be independent processes. • High NO{sub 3}, fresh groundwater evolved to lower NO{sub 3}, higher salinity surface water. • Inverse and direct geochemical modeling confirmed the hypotheses. • Salinization was a natural ongoing process

  10. Water use patterns of co-occurring C3 and C4 shrubs in the Gurbantonggut desert in northwestern China.

    Science.gov (United States)

    Tiemuerbieke, Bahejiayinaer; Min, Xiao-Jun; Zang, Yong-Xin; Xing, Peng; Ma, Jian-Ying; Sun, Wei

    2018-04-05

    In water-limited ecosystems, spatial and temporal partitioning of water sources is an important mechanism that facilitates plant survival and lessens the competition intensity of co-existing plants. Insights into species-specific root functional plasticity and differences in the water sources of co-existing plants under changing water conditions can aid in accurate prediction of the response of desert ecosystems to future climate change. We used stable isotopes of soil water, groundwater and xylem water to determine the seasonal and inter- and intraspecific differences variations in the water sources of six C 3 and C 4 shrubs in the Gurbantonggut desert. We also measured the stem water potentials to determine the water stress levels of each species under varying water conditions. The studied shrubs exhibited similar seasonal water uptake patterns, i.e., all shrubs extracted shallow soil water recharged by snowmelt water during early spring and reverted to deeper water sources during dry summer periods, indicating that all of the studied shrubs have dimorphic root systems that enable them to obtain water sources that differ in space and time. Species in the C 4 shrub community exhibited differences in seasonal water absorption and water status due to differences in topography and rooting depth, demonstrating divergent adaptations to water availability and water stress. Haloxylon ammodendron and T. ramosissima in the C 3 /C 4 mixed community were similar in terms of seasonal water extraction but differed with respect to water potential, which indicated that plant water status is controlled by both root functioning and shoot eco-physiological traits. The two Tamarix species in the C 3 shrub community were similar in terms of water uptake and water status, which suggests functional convergence of the root system and physiological performance under same soil water conditions. In different communities, Haloxylon ammodendron differed in terms of summer water extraction

  11. The Importance of Holding Water: Salinity and Chemosensory Cues Affect Zebrafish Behavior.

    Science.gov (United States)

    Mahabir, Samantha; Gerlai, Robert

    2017-10-01

    The zebrafish is becoming a popular model organism for studying numerous biological phenomena. Among these are brain function and behavior, including social behavior. Although usually neglected, few studies have already demonstrated that even trivial factors, such as features of the holding water may alter zebrafish behavior. In this study, we employed a 2 × 2 between-subject experimental design, exposing zebrafish to water of either high or low salinity and with chemosensory/olfactory cues of conspecifics either present or absent (while maintaining pH, temperature, nitrate, nitrite, and ammonia levels constant). We presented moving images of conspecifics to experimental zebrafish and analyzed their behavioral responses using video tracking. We found significant interaction between salinity and olfactory cues. For example, zebrafish exposed to their home tank water (high salinity with chemosensory/olfactory cues present) stayed significantly closer to the bottom of their tank compared with fish exposed to the other water conditions, and fish exposed to water with chemosensory/olfactory cues significantly reduced their turns compared with fish exposed to water without chemosensory/olfactory cues. These differences signify the impact environmental factors, for example, fluctuations in salinity level and presence or absence of chemosensory/olfactory cues, may have on zebrafish behavior. We conclude that maintaining stable environmental conditions and specifying and reporting them precisely are important for reducing error variation and for making results across independent studies more comparable.

  12. Hyper-saline produced water treatment for beneficial use

    NARCIS (Netherlands)

    Al-Furaiji, Mustafa

    2016-01-01

    Producing oil and gas is always accompanied with large amounts of effluent water, called “produced water” (PW). These huge quantities of water can be used (if treated efficiently and economically) for many useful purposes like industrial applications, irrigation, cattle and animal consumption, and

  13. Evidence for deep-water deposition of abyssal Mediterranean evaporites during the Messinian salinity crisis

    Science.gov (United States)

    Christeleit, Elizabeth C.; Brandon, Mark T.; Zhuang, Guangsheng

    2015-10-01

    Scientific drilling of the abyssal evaporites beneath the deepest parts of the Mediterranean basin gave rise to the idea that the Mediterranean sea completely evaporated at the end of the Messinian. Herein, we show, using new organic geochemical data, that those evaporites were deposited beneath a deep-water saline basin, not in a subaerial saltpan, as originally proposed. Abundant fossil organic lipids were extracted from evaporites in Mediterranean Deep Sea Drilling Project cores. The archaeal lipid distribution and new analyses, using the ACE salinity proxy and TEX86 temperature proxy, indicate that surface waters at the time of evaporite deposition had normal marine salinity, ranging from ∼26 to 34 practical salinity units, and temperatures of 25-28 °C. These conditions require a deep-water setting, with a mixed layer with normal marine salinity and an underlying brine layer at gypsum and halite saturation. After correction for isostatic rebound, our results indicate maximum drawdown of ∼2000 m and ∼2900 m relative to modern sea level in the western and eastern Mediterranean basins, respectively. Our results are consistent with previously proposed scenarios for sea level drawdown based on both subaerial and submarine incision and backfilling of the Rhone and Nile rivers, which require Messinian sea level drops of ∼1300 m and ∼200 m, respectively. This study provides new evidence for an old debate and also demonstrates the importance of further scientific drilling and sampling of deeper part of the abyssal Messinian units.

  14. Mulching for sustainable use of saline water to grow tomato in sultanate of oman

    International Nuclear Information System (INIS)

    Wahaibi, N.S.A.; Hussain, N.; Rawah, A.A.

    2007-01-01

    Tomato is grown in 991 hectares with production of 44477 tons in the sultanate of Oman. It is very important vegetable crop of Oman oat present being an integral part of daily diet of the people in various from like salad. Ketchup and kitchen cooking. Oman agriculture relies upon groundwater only, a major portion of which is saline that may concentrate further with the ever increasing pumping and probable seawater intrusions. Hence, the use of saline water is inevitable that can ultimately salinized the good productive soils. The production potential of these soils will gradually decrease and sustainability cannot be kept. This study was conducted to manage the saline water for avoiding bad effect on crop yields and soil health. A field experiment was conducted on tomato (Ginan variety) crop. Two mulching materials: organic matter (from date palm residues) and black plastic sheet, were tested in comparison to control (without any mulch). Two saline waters (EC=3 and 6 dSm/sup -1/) were used for irrigation. Uniform dose of fertilizers was applied. Four pickings of tomato were obtained and yield data were recorded EC moisture % age and temperature of soils were recorded after harvesting of crops. It was observed that data palm mulch proved as the most superior in terms of tomato fruit yield and control of increase in soil EC and temperature. It was followed by black plastic mulch. Both types of mulches indicated significant differences over control as well as among each other. (author)

  15. Effect of salinity and ascorbic acid on growth, water and osmotic relations of Lepidium sativum

    Directory of Open Access Journals (Sweden)

    Azadeh Najjar-Khodabakhsh

    2015-06-01

    Full Text Available Soil salinity is a serious environmental problem in arid and semi-arid regions that have negative impacts on crop production. In this research, because of medicinal and nutritional importance of the garden cress (Lepidium sativum plant, the interactive effects of salinity (225 mM NaCl and ascorbic acid (1 mM were evaluated on growth and its water relations. A completely randomized design with four replications was conducted under controlled conditions. The results showed that salinity decreased growth, relative water content, osmotic potential and soluble proteins and increased soluble sugars, amino acids and proline contents. Many of salinity damaged characteristic were improved by adding exogenous ascorbic acid to salty environment. Exogenous ascorbic acid alone, in comparison with control, enhanced the growth of garden cress by increasing relative water content, soluble sugars and soluble proteins contents. The results indicated that usage of ascorbic acid, as an antioxidant, reduced harmful effects of salinity stress and led to growth improvement in garden cress plants.

  16. A method for U-Th isotopic analysis of saline and geothermal waters

    OpenAIRE

    Innocent, Christophe

    2011-01-01

    International audience; A method for U-Th isotopic analysis dedicated to saline and geothermal, including Si-rich waters has been performed. It involves a chemical separation step using a Chelex 100® resin, then a further U and Th purification step involving a specific UTEVA® resin. Both elements are analyzed together on a MC/ICP-MS. This method has been successfully applied to different water samples (Bouillante, French Guadalupe ; Vendée, France ; Iceland geothermal waters).

  17. Radionuclides and heavy metal uptake by lolium italicum plant as affected by saline water irrigation

    International Nuclear Information System (INIS)

    Ramadan, A.A.; Aly, A.I.; Helal, M.H.

    2001-01-01

    The use of saline waters to grow crops on increasingly metal polluted soils is becoming a common practice in the arid regions. Nevertheless, the effects of soil and water salinity on radionuclides and heavy metal fluxes in polluted areas are not well understood. The aim of this study was to evaluate in pot experiments the plant uptake of cesium-137, Co-60, Mn-54, Zinc, cadmium and copper from a polluted alluvial aridisol as affected by salt water irrigation. Fertilized soil material was planted in pots with L. Italicum for 18 weeks under greenhouse conditions. The plants were irrigated either with water or with salt solution of variable variable Na/Ca ratio and harvested every 5-7 weeks. In addition to elemental analysis of plants and soil extracts root length was determined by a gridline intersect method and the viable part of the roots was estimated by a root protein inex. Saline (Na) water irrigation increased cobalt-60, manganese-54 and heavy metal solubility in soil, reduced root viability and enhanced the uptake of Co-60, Mn-54, Cd, Cu, Zn and Na by L.italicum and reduced the uptake of Cs-137. Ca counteracted these effects partly. The presented results demonstrated a dual effect of salinity on radiouclides and heavy metal availability to plants and suggest a relationship between root mortality and the enhanced Co-60, Mn-54, and heavy metake ny salt stressed plants

  18. Tap Water Versus Sterile Normal Saline in Wound Swabbing: A Double-Blind Randomized Controlled Trial.

    Science.gov (United States)

    Chan, Mun Che; Cheung, Kin; Leung, Polly

    2016-01-01

    The use of tap water as a wound-cleansing agent is becoming more common in clinical practice, especially in community settings. The aim of this study was to test whether there are differences in wound infection and wound healing rates when wounds are cleansed with tap water or sterile normal saline. Double-blinded randomized controlled trial. Subjects were recruited from the community nursing service of a local hospital in Hong Kong. The target sample included subjects who were aged 18 years or more, and receiving chronic or acute wound care treatment. Subjects were randomly assigned to wound cleansing with tap water (experimental group) or sterile normal saline (control group). Wound assessment was conducted at each home visit, and an assessment of wound size was conducted once a week. The main outcome measures, occurrence of a wound infection and wound healing, were assessed over a period of 6 weeks. Twenty-two subjects (11 subjects in each group) with 30 wounds participated in the study; 16 wounds were managed with tap water cleansing and 14 were randomly allocated to management with the sterile normal saline group. Analysis revealed no significant difference between the experimental and control groups in the proportions of wound infection and wound healing. Study findings indicate that tap water is a safe alternative to sterile normal saline for wound cleansing in a community setting.

  19. Salinity independent volume fraction prediction in water-gas-oil multiphase flows using artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Salgado, C.M.; Pereira, Claudio M.N.A.; Brandao, Luis E.B., E-mail: otero@ien.gov.b, E-mail: cmnap@ien.gov.b, E-mail: brandao@ien.gov.b [Instituto de Engenharia Nuclear (DIRA/IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Div. de Radiofarmacos

    2011-07-01

    This work investigates the response of a volume fraction prediction system for water-gas-oil multiphase flows considering variations on water salinity. The approach is based on gamma-ray pulse height distributions pattern recognition by means the artificial neural networks (ANNs). The detection system uses appropriate fan beam geometry, comprised of a dual-energy gamma-ray source and two NaI(Tl) detectors adequately positioned outside the pipe in order measure transmitted and scattered beams. An ideal and static theoretical model for annular flow regime have been developed using MCNP-X code, which was used to provide training, test and validation data for the ANN. More than 500 simulations have been done, in which water salinity have been ranged from 0 to 16% in order to cover a most practical situations. Validation tests have included values of volume fractions and water salinity different from those used in ANN training phase. The results presented here show that the proposed approach may be successfully applied to material volume fraction prediction on watergas- oil multiphase flows considering practical (real) levels of variations in water salinity. (author)

  20. Salinity independent volume fraction prediction in water-gas-oil multiphase flows using artificial neural networks

    International Nuclear Information System (INIS)

    Salgado, C.M.; Pereira, Claudio M.N.A.; Brandao, Luis E.B.

    2011-01-01

    This work investigates the response of a volume fraction prediction system for water-gas-oil multiphase flows considering variations on water salinity. The approach is based on gamma-ray pulse height distributions pattern recognition by means the artificial neural networks (ANNs). The detection system uses appropriate fan beam geometry, comprised of a dual-energy gamma-ray source and two NaI(Tl) detectors adequately positioned outside the pipe in order measure transmitted and scattered beams. An ideal and static theoretical model for annular flow regime have been developed using MCNP-X code, which was used to provide training, test and validation data for the ANN. More than 500 simulations have been done, in which water salinity have been ranged from 0 to 16% in order to cover a most practical situations. Validation tests have included values of volume fractions and water salinity different from those used in ANN training phase. The results presented here show that the proposed approach may be successfully applied to material volume fraction prediction on watergas- oil multiphase flows considering practical (real) levels of variations in water salinity. (author)

  1. Experimental studies of low salinity water flooding in carbonate reservoirs: A new promising approach

    DEFF Research Database (Denmark)

    Zahid, Adeel; Shapiro, Alexander; Skauge, Arne

    2012-01-01

    reservoirs. In this paper, we have experimentally investigated the oil recovery potential of low salinity water flooding for carbonate rocks. We used both reservoir carbonate and outcrop chalk core plugs. The flooding experiments were carried out initially with the seawater, and afterwards additional oil......Low salinity water flooding is well studied for sandstone reservoirs, both laboratory and field tests have showed improvement in the oil recovery in many cases. Up to very recently, the low salinity effect has been indeterminated for carbonates. Most recently, Saudi Aramco reported that substantial...... recovery was evaluated by sequential injection of various diluted seawater. The experiments applied stepwise increase in flow rate to eliminate the influence of possible capillary end effect. The total oil recovery, interaction of the different ions with the rock, and the wettability changes were studied...

  2. Estimation of solar energy resources for low salinity water desalination in several regions of Russia

    Science.gov (United States)

    Tarasenko, A. B.; Kiseleva, S. V.; Shakun, V. P.; Gabderakhmanova, T. S.

    2018-01-01

    This paper focuses on estimation of demanded photovoltaic (PV) array areas and capital expenses to feed a reverse osmosis desalination unit (1 m3/day fresh water production rate). The investigation have been made for different climatic conditions of Russia using regional data on ground water salinity from different sources and empirical dependence of specific energy consumption on salinity and temperature. The most optimal results were obtained for Krasnodar, Volgograd, Crimea Republic and some other southern regions. Combination of salinity, temperature and solar radiation level there makes reverse osmosis coupled with photovoltaics very attractive to solve infrastructure problems in rural areas. Estimation results are represented as maps showing PV array areas and capital expenses for selected regions.

  3. Monitoring and Modelling of Salinity Behaviour in Drinking Water Ponds in Southern Bangladesh

    Science.gov (United States)

    Hoque, M. A.; Williams, A.; Mathewson, E.; Rahman, A. K. M. M.; Ahmed, K. M.; Scheelbeek, P. F. D.; Vineis, P.; Butler, A. P.

    2015-12-01

    Drinking water in southern Bangladesh is provided by a variety of sources including constructed storage ponds, seasonal rainwater and, ubiquitously saline, shallow groundwater. The ponds, the communal reservoirs for harvested rainwater, also tend to be saline, some as high as 2 g/l. Drinking water salinity has several health impacts including high blood pressure associated major risk factor for several cardio-vascular diseases. Two representative drinking water ponds in Dacope Upazila of Khulna District in southwest Bangladesh were monitored over two years for rainfall, evaporation, pond and groundwater level, abstraction, and solute concentration, to better understand the controls on drinking water salinity. Water level monitoring at both ponds shows groundwater levels predominantly below the pond level throughout the year implying a downward gradient. The grain size analysis of the underlying sediments gives an estimated hydraulic conductivity of 3E-8 m/s allowing limited seepage loss. Water balance modelling indicates that the seepage has a relatively minor effect on the pond level and that the bulk of the losses come from the combination of evaporation and abstraction particularly in dry season when precipitation, the only inflow to the pond, is close to zero. Seasonal variation in salinity (electrical conductivities, EC, ranged between 1500 to 3000 μS/cm) has been observed, and are primarily due to dilution from rainfall and concentration from evaporation, except on one occasion when EC reached 16,000 μS/cm due to a breach in the pond levee. This event was analogous to the episodic inundation that occurs from tropical cyclone storm surges and appears to indicate that such events are important for explaining the widespread salinisation of surface water and shallow groundwater bodies in coastal areas. A variety of adaptations (either from practical protection measures) or novel alternative drinking sources (such as aquifer storage and recovery) can be applied

  4. [Soil salinity in greenland irrigated with reclaimed water and risk assessment].

    Science.gov (United States)

    Pan, Neng; Chen, Wei-Ping; Jiao, Wen-Tao; Zhao, Zhong-Ming; Hou, Zhen-An

    2012-12-01

    Compared to drinking water or groundwater, reclaimed water contains more salts. Therefore, the effects of application of reclaimed water on the soil salinity have received great attentions. To evaluate the potential risks posed by long-term reclaimed water irrigation, we collected surface soil samples from urban green lands and suburban farmlands of Beijing represented different irrigation durations. The electrical conductivity (EC) and sodium adsorption ratio (SAR) in soils were measured subsequently. Both EC1:5 and SAR1.5 from the green land and farmland soils irrigated with reclaimed water were significantly higher than those of control treatments (drinking water or groundwater irrigation). The EC1:5 values increased by 12.4% and 84.2% than control treatments in the greenland and farmland, respectively. The SAR1:5 values increased by 64.5% and 145.8% than control treatments, respectively. No significant differences of both EC1:5 and SAR1:5 were found between of 0-10 cm and 10-20 cm soil layer. A slight decrease of soil porosity was observed. The field investigation suggested there was a high potential of soil salinization under long-term reclaimed water irrigation. Proper management practices should be implemented to minimize the soil salinity accumulation risk when using reclaimed water for irrigation in Beijing.

  5. Influence of Water Salinity on Air Purification from Hydrogen Sulfide

    Directory of Open Access Journals (Sweden)

    Leybovych L.I.

    2015-12-01

    Full Text Available Mathematical modeling of «sliding» water drop motion in the air flow was performed in software package FlowVision. The result of mathematical modeling of water motion in a droplet with diameter 100 microns at the «sliding» velocity of 15 m/s is shown. It is established that hydrogen sulfide oxidation occurs at the surface of phases contact. The schematic diagram of the experimental setup for studying air purification from hydrogen sulfide is shown. The results of the experimental research of hydrogen sulfide oxidation by tap and distilled water are presented. The dependence determining the share of hydrogen sulfide oxidized at the surface of phases contact from the dimensionless initial concentration of hydrogen sulfide in the air has been obtained.

  6. Influence of Microsprinkler Irrigation Amount on Water, Soil, and pH Profiles in a Coastal Saline Soil

    Directory of Open Access Journals (Sweden)

    Linlin Chu

    2014-01-01

    Full Text Available Microsprinkler irrigation is a potential method to alleviate soil salinization. After conducting a homogeneous, highly saline, clayey, and coastal soil from the Bohai Gulf in northern China in a column experiment, the results show that the depth of the wetting front increased as the water amount applied increased, low-salinity and low-SAR enlarged after irrigation and water redistribution, and the soil pH increased with an increase in irrigation amount. We concluded that a water amount of 207 mm could be used to reclaim the coastal saline soil in northern China.

  7. Influence of microsprinkler irrigation amount on water, soil, and pH profiles in a coastal saline soil.

    Science.gov (United States)

    Chu, Linlin; Kang, Yaohu; Wan, Shuqin

    2014-01-01

    Microsprinkler irrigation is a potential method to alleviate soil salinization. After conducting a homogeneous, highly saline, clayey, and coastal soil from the Bohai Gulf in northern China in a column experiment, the results show that the depth of the wetting front increased as the water amount applied increased, low-salinity and low-SAR enlarged after irrigation and water redistribution, and the soil pH increased with an increase in irrigation amount. We concluded that a water amount of 207 mm could be used to reclaim the coastal saline soil in northern China.

  8. Water Loss Due to Increasing Planted Vegetation over the Badain Jaran Desert, China

    Directory of Open Access Journals (Sweden)

    Xunhe Zhang

    2018-01-01

    Full Text Available Water resources play a vital role in ecosystem stability, human survival, and social development in drylands. Human activities, such as afforestation and irrigation, have had a large impact on the water cycle and vegetation in drylands over recent years. The Badain Jaran Desert (BJD is one of the driest regions in China with increasing human activities, yet the connection between human management and the ecohydrology of this area remains largely unclear. In this study, we firstly investigated the ecohydrological dynamics and their relationship across different spatial scales over the BJD, using multi-source observational data from 2001 to 2014, including: total water storage anomaly (TWSA from Gravity Recovery and Climate Experiment (GRACE, normalized difference vegetation index (NDVI from Moderate Resolution Imaging Spectroradiometer (MODIS, lake extent from Landsat, and precipitation from in situ meteorological stations. We further studied the response of the local hydrological conditions to large scale vegetation and climatic dynamics, also conducting a change analysis of water levels over four selected lakes within the BJD region from 2011. To normalize the effect of inter-annual variations of precipitation on vegetation, we also employed a relationship between annual average NDVI and annual precipitation, or modified rain-use efficiency, termed the RUEmo. A focus of this study is to understand the impact of the increasing planted vegetation on local ecohydrological systems over the BJD region. Results showed that vegetation increases were largely found to be confined to the areas intensely influenced by human activities, such as croplands and urban areas. With precipitation patterns remaining stable during the study period, there was a significant increasing trend in vegetation greenness per unit of rainfall, or RUEmo over the BJD, while at the same time, total water storage as measured by satellites has been continually decreasing since

  9. Study of the Effect of Clay Particles on Low Salinity Water Injection in Sandstone Reservoirs

    Directory of Open Access Journals (Sweden)

    Sina Rezaei Gomari

    2017-03-01

    Full Text Available The need for optimal recovery of crude oil from sandstone and carbonate reservoirs around the world has never been greater for the petroleum industry. Water-flooding has been applied to the supplement primary depletion process or as a separate secondary recovery method. Low salinity water injection is a relatively new method that involves injecting low salinity brines at high pressure similar to conventional water-flooding techniques, in order to recover crude oil. The effectiveness of low salinity water injection in sandstone reservoirs depends on a number of parameters such as reservoir temperature, pressure, type of clay particle and salinity of injected brine. Clay particles present on reservoir rock surfaces adsorb polar components of oil and modify wettability of sandstone rocks to the oil-wet state, which is accountable for the reduced recovery rates by conventional water-flooding. The extent of wettability alteration caused by three low salinity brines on oil-wet sandstone samples containing varying clay content (15% or 30% and type of clay (kaolinite/montmorillonite were analyzed in the laboratory experiment. Contact angles of mica powder and clay mixture (kaolinite/montmorillonite modified with crude oil were measured before and after injection with three low salinity sodium chloride brines. The effect of temperature was also analyzed for each sample. The results of the experiment indicate that samples with kaolinite clay tend to produce higher contact angles than samples with montmorillonite clay when modified with crude oil. The highest degree or extent of wettability alteration from oil-wet to intermediate-wet state upon injection with low salinity brines was observed for samples injected with brine having salinity concentration of 2000 ppm. The increase in temperature tends to produce contact angles values lying in the higher end of the intermediate-wet range (75°–115° for samples treated at 50 °C, while their corresponding

  10. Simulation studies of long-term saline water use: model validation and evaluation of schedules

    NARCIS (Netherlands)

    Tedeschi, A.; Menenti, M.

    2002-01-01

    In the Mediterranean environment characterized by hot, dry summers, a hydrologically oriented field experiment on vegetable crops was carried out between 1988 and 1993 at a site near Naples, Italy. The objective of the experiment was to study the impact of saline water on crop yield and soil

  11. Investigations of PAA degradation in aqueous solutions: Impacts of water hardness, salinity and DOC

    Science.gov (United States)

    Peracetic acid (PAA) is used in aquaculture under various conditions for disinfection purposes. However, there is lack of information about its environmental fate. Therefore, the impact of water hardness, salinity, and dissolved organic carbon (DOC) on PAA-degradation within 5 hours was investigat...

  12. On the occurrence of high salinity waters off the east coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Sasamal, S.K.

    Some high salinity waters (35 x 10 super(3)) are observed in the surface layer of the western Bay of Bengal during northeast monsoon and in subsurface layer during southwest monsoon. These values are discussed on the basis of prevaling climaitc...

  13. Effect of irrigation with sea water on soil salinity and yield of oleic sunflower

    NARCIS (Netherlands)

    Farhadi Machekposhti, Mabood; Shahnazari, Ali; Ahmadi, Mirkhalegh Z.; Aghajani, Ghasem; Ritzema, Henk

    2017-01-01

    A field trial was carried out in 2013 and 2014 in a research field near Sari (Iran), to study the effect of irrigation with Caspian Sea water on soil salinity, growth parameters and yield components of oleic sunflower. The experiment was conducted with 4 levels of blending viz. 0% (S0)

  14. Monitoring of Soil Chemical Characteristics with Time as Affected by Irrigation with Saline Water

    International Nuclear Information System (INIS)

    Mostafa, A.Z.; Galal, Y.G.M.; Lotfy, S.M.

    2015-01-01

    A lysimeter study was conducted to investigate the effect of irrigation with saline water on soil chemical characteristics at two depth (0-20) and (20-40 cm). Both fertilized (60, 120 Kg N/ha) and unfertilized (0) soil were simulated in a total of 84 lysimeter. Data indicated that the electric conductivity (EC) values tended to increase with time intervals also EC- values as affected by soil depth after 105 days were high in 20 cm depth as compared to 40 cm depth. Chloride concentration did not reflect great variations as affected by time of nitrogen application where the values were nearly closed to each other. At the end of the experiment, much of Cl- content was occurred in the second layer of soil depth (20-40) as compared to depth of 0-20 cm. This was the case under all salinity levels. The irrigation with fresh water did not reflect any significant different in EC values between 120 Kg N/ha, 60 Kg N/ha or soil depth, however, it tend to increase with increasing water salinity levels. There were no much differences between the nitrogen application time (T1, T2 and T3). In contrast with Cl-, sodium was remained in the upper layer of 0-20 cm soil depth but still increase with increasing water salinity levels.

  15. Carbon dioxide degassing in fresh and saline water. II: Degassing performance of an air-lift

    DEFF Research Database (Denmark)

    Moran, Damian

    2010-01-01

    A study was undertaken to measure the efficiency with which carbon dioxide was stripped from freshwater (0‰) and saline water (35‰ NaCl) passing through an air-lift at 15 °C. The air-lift was constructed of 50 mm (OD) PVC pipe submerged 95 cm in a tank, had an adjustable air injection rate, and c...

  16. Osmoregulatory physiology and rapid evolution of salinity tolerance in threespine stickleback recently introduced to fresh water

    Science.gov (United States)

    Divino, Jeffrey N; Monette, Michelle Y.; McCormick, Stephen; Yancey, Paul H.; Flannery, Kyle G.; Bell, Michael A.; Rollins, Jennifer L.; von Hippel, Frank A.; Schultz, Eric T.

    2016-01-01

    Background: Post-Pleistocene diversification of threespine stickleback in fresh water offers a valuable opportunity to study how changes in environmental salinity shape physiological evolution in fish. In Alaska, the presence of both ancestral oceanic populations and derived landlocked populations, including recent lake introductions, allows us to examine rates and direction of evolution of osmoregulation following halohabitat transition.

  17. Evaluation of soil and water salinity for irrigation in North-eastern ...

    African Journals Online (AJOL)

    GREG

    2013-05-08

    May 8, 2013 ... proper understanding of the hazard and appropriate miti- gation measures. Salt affected soils and the ... made us to assess the salinity hazard for soils and water of Fursa irrigation project. Therefore, the objective of this ... Records from Elliwuha metrological station showed that the mean annual rainfall was ...

  18. Interaction Study of Clay bearing Amphibolite-Crude Oil-Saline Water

    Indian Academy of Sciences (India)

    26

    Low saline water flooding (LSWF) had proved to be an efficient method for enhanced oil recovery. 34 in clay bearing hydrocarbon reservoirs but the interaction mechanisms among in-situ rocks - fluids. 35 and injection fluids within the reservoir has not yet properly known. Understanding molecular. 36 level interaction ...

  19. Monitoring of soil chemical characteristics with time as affected by irrigation with saline water

    International Nuclear Information System (INIS)

    Mostafa, A. Z.; Galal, Y.G.M.; Lotfy, S.M.

    2012-01-01

    A lysimeter study was conducted to investigate the effect of irrigation with saline water on soil chemical characteristics at two depth (0-20) and (20-40 cm).Both fertilized (60, 120 KgN/ha) and unfertilized (0) soil were simulated in a total of 84 lysimeter. Data indicated that the electric conductivity (EC) values tended to increase with time intervals also EC-values as affected by soil depth after 105 days were high in 20 cm depth as compared to 40 cm depth. Chloride concentration did not reflect great variations as affected by time of nitrogen application where the values were nearly closed to each other. At the end of the experiment, much of Cl - content was occurred in the second layer of soil depth (20-40) as compared to depth of 0-20 cm. This was the case under all salinity levels. The irrigation with fresh water did not reflect any significant different in EC values between 120 KgN/ha , 60 KgN/ha or soil depth, however, it tend to increase with increasing water salinity levels. There were no much differences between the nitrogen application time (T1, T2 and T3). In contrast with Cl - , sodium was remained in the upper layer of 0-20 cm soil depth but still increase with increasing water salinity levels.

  20. Final Technical Report: Effects of Changing Water and Nitrogen Inputs on a Mojave Desert Ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Stanley D. [University of Nevada, Las Vegas; Nowak, Robert S. [University of Nevada, Reno

    2007-11-30

    Questions addressed under this grant shared the common hypothesis that plant and ecosystem performance will positively respond to the augmentation of the most limiting resources to plant growth in the Mojave Desert, e.g., water and nitrogen. Specific hypothesis include (1) increased summer rainfall will significantly increase plant production thorugh an alleviation of moisture stress in the dry summer months, (2) N-deposition will increase plan production in this N-limited system, particularly in wet years or in concert with added summer rain, and (3) biological crust disturbance will gradually decrease bio-available N, with concomitant long-term reductions in photosynthesis and ANPP. Individual plan and ecosystem responses to global change may be regulated by biogeochemical processes and natural weather variability, and changes in plant and ecosystem processes may occur rapidly, may occur only after a time lag, or may not occur at all. During the first PER grant period, we observed changes in plant and ecosystem processes that would fall under each of these time-response intervals: plant and ecosystem processes responded rapidly to added summer rain, whereas most processes responded slowly or in a lag fashion to N-deposition and with no significant response to crust disturbance. Therefore, the primary objectives of this renewal grant were to: (1) continue ongoing measurements of soil and plant parameters that assess primary treatment responses; (2) address the potential heterogeneity of soil properties and (3) initiate a new suite of measurements that will provide data necessary for scaling/modeling of whole-plot to ecosystem-level responses. Our experimental approach included soil plan-water interactions using TDR, neutron probe, and miniaturized soil matric potential and moisture sensors, plant ecophysiological and productivity responses to water and nitrogen treatments and remote sensing methodologies deployed on a radio control platform.

  1. Tree water potentials supporting an explanation for the occurrence of Vachellia erioloba in the Namib Desert (Namibia

    Directory of Open Access Journals (Sweden)

    Joachim H. A. Krug

    2017-09-01

    Full Text Available Background Site-vegetation relations of Vachellia erioloba, Faidherbia albida, Euclea pseudebenus and Tamarix usneoides in two contrasting locations in the Namib Desert (Namibia were evaluated with the goal to relate soil water availability to the occurrence of trees under hyper-arid conditions. Methods Plant water potentials were measured using a pressure chamber in the field. Pre-dawn water potentials were assessed to reflect the soil water potential of the rhizosphere. Midday water potentials were measured to assess the strongest negative water potential applied by the sample trees. Results Pre-dawn water potentials and midday water potentials indicated access to soil water in the rhizosphere and by this, provide an explanation for an occurrence of V. erioloba within the extreme environmental conditions of sand dunes in the Namib Desert. Diurnal ranges seem to reflect more and less suitable stands, in terms of soil water availability, within the sampling sites. While the impact of the ephemeral Kuiseb river on soil water availability was assessed through the four species’ plant-internal water relations, comparable pre-dawn water potentials of V. erioloba at both sites indicate soil water availability also in the dunes of Namibrand. The extreme midday water potentials of the dune plants possibly show the upper limit of tolerance for V. erioloba. Conclusions The preliminary data provide an explanation of the occurrence and distribution of the investigated species in beds of ephemeral rivers and on dunes under the hyper-arid climatic conditions of the Namib Desert and qualify suitability within the assessed sites. Understanding the plant-physiological processes and assessing the plant-internal water potential provides a valuable tool to evaluate soil water availability within the rhizosphere and to describe an adaptation potential of investigated species. The comparability of pre-dawn water potentials at both sites indicates unexpected soil

  2. The effect of process water salinity on flotation of copper ore from Lubin mining region (SW Poland

    Directory of Open Access Journals (Sweden)

    Bakalarz Alicja

    2017-01-01

    Full Text Available The process water used for the flotation of sedimentary copper ore in ore concentration plants in KGHM Polska Miedz S.A. were characterized. The process water used in the flotation circuits is heavily saline. It contains between 25 and 45 g/dm3 of soluble components, and the main constituent, in about 75%, is NaCl. Process water used for flotation consists of reclaimed water from the tailing dam and mine water. The effect of process water salinity on the processes of copper flotation from the Lubin mine area was described. The results of laboratory flotation experiments conducted in tap water and in water of different salinity levels were compared. The effect of the salinity of water within specified concentration limits was generally found to be beneficial for upgrading of the examined ore.

  3. Photocatalytic efficiency of titania photocatalysts in saline waters

    Directory of Open Access Journals (Sweden)

    Albrbar Asma Juma

    2014-01-01

    Full Text Available The photocatalytic efficiency of the recently synthesized TiO2 powder, named P160, of the degradation of dye Dye C.I. Reactive orange 16 in natural and artificial seawater was investigated in comparison to its efficiency in deionized water and the efficiency of a standard TiO2 powder Degusa P25. It was shown that the photocatalytic efficiency of P160 was slightly higher than that of P25, probably due to slightly higher specific surface area, higher pore volume and larger pores of the powder P160. The efficiency of both photocatalysts in natural and artificial seawater was significantly lower than that in deionized water. The overall rate of dye degradation for both types of photocatalysts is litle higher in artificial seawater than in natural seawater, which shows the influence of organic compounds naturally present in seawater on the photocatalysts activity. A saturation Langmuir-type relationship between the initial degradation rate and the initial dye concentration indicates that the adsorption plays a role in the photocatalytic reaction. The photodegradation rate constant k, which represents the maximum reaction rate, has similar values for P25 and P160 in all types of water due to the similar properties of the photocatalysts. [Projekat Ministarstva nauke Republike Srbije, br III 45019

  4. An inductive conductivity meter for monitoring the salinity of dialysis water

    DEFF Research Database (Denmark)

    Diamond, J.M.

    1970-01-01

    An inductive conductivity meter is described, especially adapted as a salinity monitor for dialysis water. Salinity are given. The principal problems of the inductive conductivity meter result from the low conductivity of electrolytes. The weak coupling due to the electrolyte means that stray...... coupling must be reduced to a very low level. This has been accomplished by means of a heavy copper eddy-current shield, which reduces the unwanted coupling to a level corresponding to a conductivity increment of the order of 10-8 ¿-1. cm-1. The effect of parasitic impedances in the receiver core...

  5. Leaf gas exchange in cowpea and CO2 efflux in soil irrigated with saline water

    OpenAIRE

    Oliveira, Wanderson J. de; Souza, Edivan R. de; Cunha, Jailson C.; Silva, Ênio F. de F. e; Veloso, Venâncio de L.

    2017-01-01

    ABSTRACT Leaf gas exchanges in plants and soil respiration are important tools for assessing the effects of salinity on the soil-plant system. An experiment was conducted with cowpea irrigated with saline water (0, 2.5, 5.0, 7.5, 10.0 and 12.5 dS m-1) prepared with two sources: NaCl and a mixture of Ca, Mg, Na, K and Cl ions in a randomized block design and a 6 x 2 factorial scheme, with four replicates, totaling 48 experimental plots. At 20 days after planting (DAP), plants were evaluated fo...

  6. Urban "accidental" wetlands mediate water quality and heat exposure for homeless populations in a desert city

    Science.gov (United States)

    Palta, M.

    2015-12-01

    In urban settings where humans interact in complex ways with ecosystems, there may be hidden or unanticipated benefits (services) or harm (disservices) conferred by the built environment. We examined interactions of a highly vulnerable population, the homeless, with urban waterways and wetlands in the desert city of Phoenix, Arizona, U.S.A. Climate change models project increases in heat, droughts, and extreme floods for the southwestern U.S. These projected changes pose a number of problems for sustainability and quality of future water supply, and the ability of human populations to mitigate heat stress and avoid fatalities. Urban wetlands that are created "accidentally" (by water pooling in abandoned areas of the landscape) have many structural (e.g., soils and hydrology) and functional (e.g., high denitrification) elements that mimic natural, unaltered aquatic systems. Accidental wetland systems in the dry bed of the Salt River, fed by storm and waste water from urban Phoenix, are located within economically depressed sections of the city, and show the potential for pollutant and heat mitigation. We used a mixed-method socio-ecological approach to examine wetland ecosystem functions and the ways in which homeless populations utilize Salt River wetlands for ecosystem services. Interviews and trash surveys indicated that homeless people are accessing and utilizing the wetlands as a source of running water, for sanitary and heat mitigation services, and for recreation and habitation. Environmental monitoring demonstrated that the wetlands can provide a reliable source of running water, nutrient and pathogen removal, heat mitigation, and privacy, but they may also pose a health risk to individuals coming in contact with the water through drinking or bathing. Whether wetlands provided a net benefit vs. harm varied according to site, season, and particular service, and several tradeoffs were identified. For example, heat is highest during the summer storm season

  7. Irrigation with saline-sodic water: effects on two clay soils

    Directory of Open Access Journals (Sweden)

    Giovanna Cucci

    2013-05-01

    Full Text Available The results of a 4-year experiment aimed at evaluating the effect of irrigation with saline-sodic water on the soil are reported. The research was carried out at the Campus of the Agricultural Faculty of Bari University (Italy on 2 clay soils (Bologna – T1 and Locorotondo – T2. The soils were cropped to borlotto bean (Phaseolus vulgaris L., capsicum (Capsicum annuum L., sunflower (Helianthus annuus L., wheat (Triticum durum Desf grown in succession; the crops were irrigated with 9 saline-sodic types of water and subjected to two different leaching fractions (10% and 20% of the watering volume. The 9 solutions were obtained dissolving in de-ionised water weighted amounts of sodium chloride (NaCl and calcium chloride (CaCl2, deriving from the combination of 3 saline concentrations and 3 sodicity levels. The crops were irrigated whenever the water lost by evapotranspiration from the soil contained in the pots was equal to 30% of the soil maximum available water. The results showed that, though the soils were leached during the watering period, they showed a high salt accumulation. Consequently, the saturated soil extract electrical conductivity increased from initial values of 0.65 and 0.68 dS m-1 to 11.24 and 13.61 dS m-1 at the end of the experiment, for the soils T1 and T2, respectively. The saline concentration increase in irrigation water caused in both soils a progressive increase in exchangeable sodium, and a decrease in exchangeable calcium and non-significant variations in exchangeable potassium (K and magnesium (Mg.

  8. Desalination and reuse of high-salinity shale gas produced water: drivers, technologies, and future directions.

    Science.gov (United States)

    Shaffer, Devin L; Arias Chavez, Laura H; Ben-Sasson, Moshe; Romero-Vargas Castrillón, Santiago; Yip, Ngai Yin; Elimelech, Menachem

    2013-09-03

    In the rapidly developing shale gas industry, managing produced water is a major challenge for maintaining the profitability of shale gas extraction while protecting public health and the environment. We review the current state of practice for produced water management across the United States and discuss the interrelated regulatory, infrastructure, and economic drivers for produced water reuse. Within this framework, we examine the Marcellus shale play, a region in the eastern United States where produced water is currently reused without desalination. In the Marcellus region, and in other shale plays worldwide with similar constraints, contraction of current reuse opportunities within the shale gas industry and growing restrictions on produced water disposal will provide strong incentives for produced water desalination for reuse outside the industry. The most challenging scenarios for the selection of desalination for reuse over other management strategies will be those involving high-salinity produced water, which must be desalinated with thermal separation processes. We explore desalination technologies for treatment of high-salinity shale gas produced water, and we critically review mechanical vapor compression (MVC), membrane distillation (MD), and forward osmosis (FO) as the technologies best suited for desalination of high-salinity produced water for reuse outside the shale gas industry. The advantages and challenges of applying MVC, MD, and FO technologies to produced water desalination are discussed, and directions for future research and development are identified. We find that desalination for reuse of produced water is technically feasible and can be economically relevant. However, because produced water management is primarily an economic decision, expanding desalination for reuse is dependent on process and material improvements to reduce capital and operating costs.

  9. Saline sewage treatment and source separation of urine for more sustainable urban water management.

    Science.gov (United States)

    Ekama, G A; Wilsenach, J A; Chen, G H

    2011-01-01

    While energy consumption and its associated carbon emission should be minimized in wastewater treatment, it has a much lower priority than human and environmental health, which are both closely related to efficient water quality management. So conservation of surface water quality and quantity are more important for sustainable development than green house gas (GHG) emissions per se. In this paper, two urban water management strategies to conserve fresh water quality and quantity are considered: (1) source separation of urine for improved water quality and (2) saline (e.g. sea) water toilet flushing for reduced fresh water consumption in coastal and mining cities. The former holds promise for simpler and shorter sludge age activated sludge wastewater treatment plants (no nitrification and denitrification), nutrient (Mg, K, P) recovery and improved effluent quality (reduced endocrine disruptor and environmental oestrogen concentrations) and the latter for significantly reduced fresh water consumption, sludge production and oxygen demand (through using anaerobic bioprocesses) and hence energy consumption. Combining source separation of urine and saline water toilet flushing can reduce sewer crown corrosion and reduce effluent P concentrations. To realize the advantages of these two approaches will require significant urban water management changes in that both need dual (fresh and saline) water distribution and (yellow and grey/brown) wastewater collection systems. While considerable work is still required to evaluate these new approaches and quantify their advantages and disadvantages, it would appear that the investment for dual water distribution and wastewater collection systems may be worth making to unlock their benefits for more sustainable urban development.

  10. Hyperspectral Imaging to Evaluate the Effect of IrrigationWater Salinity in Lettuce

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Lara

    2016-12-01

    Full Text Available Salinity is one of the most important stress factors in crop production, particularly in arid regions. This research focuses on the effect of salinity on the growth of lettuce plants; three solutions with different levels of salinity were considered and compared (S1 = 50, S2 = 100 and S3 = 150 mM NaCl with a control solution (Ct = 0 mM NaCl. The osmotic potential and water content of the leaves were measured, and hyperspectral images of the surfaces of 40 leaves (10 leaves per treatment were taken after two weeks of growth. The mean spectra of the leaves (n = 32,000 were pre-processed by means of a Savitzky–Golay algorithm and standard normal variate normalization. Principal component analysis was then performed on a calibration set of 28 mean spectra, yielding an initial model for salinity effect detection. A second model was subsequently proposed based on an index computing an approximation to the second derivative at the red edge region. Both models were applied to all the hyperspectral images to obtain the corresponding artificial images, distinguishing between the 28 that were used to extract the calibration mean spectra and the rest that constituted an external validation. Those virtual images were studied using analysis of variance in order to compare their ability for detecting salinity effects on the leaves. Both models showed significant differences between each salinity level, and the hyperspectral images allowed observations of the distribution of the salinity effects on the leaf surfaces, which were more intense in the areas distant from the veins. However, the index-based model is simpler and easier to apply because it is based solely on the reflectance at three different wavelengths, thus allowing for the implementation of less expensive multispectral devices.

  11. Principles of root water uptake, soil salinity and crop yield for optimizing irrigation management

    International Nuclear Information System (INIS)

    Dirksen, C.

    1983-01-01

    The paper reviews the principles of water and salt transport, root water uptake, crop salt tolerance, water quality, and irrigation methods which should be considered in optimizing irrigation management for sustained, viable agriculture with protection of the quality of land and water resources. In particular, the advantages of high-frequency irrigation at small leaching fractions with closed systems are discussed, for which uptake-weighted mean salinity is expected to correlate best with crop yields. Optimization of irrigation management depends on the scale considered. Non-technical problems which are often much harder to solve than technical problems, may well be most favourable for new projects in developing countries. (author)

  12. The Determination of Trace Metals in Saline Waters and Biological Tissues Using the Heated Graphite Atomizer

    Science.gov (United States)

    Segar, D. A.

    1971-01-01

    A selective, volatalization technique utilizing the heated graphite atomizer atomic absorption technique has been developed for the analysis of iron in sea water. A similar technique may be used to determine vanadium, copper, nickel and cobalt in saline waters when their concentrations are higher than those normally encountered'in unpolluted sea waters. A preliminary solvent extraction using ammonium pyrolidine dithiocarbamate and methyl iso-butyl ketone permits the determination of a number of elements including iron, copper, zinc, nickel, cobalt and lead in sea water. The heated graphite atomized technique has also been applied to the determination of a range of trace transition elements in marine plant and animal tissues.

  13. Effects of non-uniform root zone salinity on water use, Na+ recirculation, and Na+ and H+ flux in cotton.

    Science.gov (United States)

    Kong, Xiangqiang; Luo, Zhen; Dong, Hezhong; Eneji, A Egrinya; Li, Weijiang

    2012-03-01

    A new split-root system was established through grafting to study cotton response to non-uniform salinity. Each root half was treated with either uniform (100/100 mM) or non-uniform NaCl concentrations (0/200 and 50/150 mM). In contrast to uniform control, non-uniform salinity treatment improved plant growth and water use, with more water absorbed from the non- and low salinity side. Non-uniform treatments decreased Na(+) concentrations in leaves. The [Na(+)] in the '0' side roots of the 0/200 treatment was significantly higher than that in either side of the 0/0 control, but greatly decreased when the '0' side phloem was girdled, suggesting that the increased [Na(+)] in the '0' side roots was possibly due to transportation of foliar Na(+) to roots through phloem. Plants under non-uniform salinity extruded more Na(+) from the root than those under uniform salinity. Root Na(+) efflux in the low salinity side was greatly enhanced by the higher salinity side. NaCl-induced Na(+) efflux and H(+) influx were inhibited by amiloride and sodium orthovanadate, suggesting that root Na(+) extrusion was probably due to active Na(+)/H(+) antiport across the plasma membrane. Improved plant growth under non-uniform salinity was thus attributed to increased water use, reduced leaf Na(+) concentration, transport of excessive foliar Na(+) to the low salinity side, and enhanced Na(+) efflux from the low salinity root.

  14. Numerical Modeling of Water Flow and Salt Transport in Bare Saline Soil Subjected to Transient Evaporation

    Science.gov (United States)

    Geng, X.; Boufadel, M.; Saleh, F. S.

    2014-12-01

    It has been found that evaporation over bare soil plays an important role in subsurface solute transport processes. A numerical study, based on a density-dependent variably saturated groundwater flow model MARUN, was conducted to investigate subsurface flow and salt transport in bare saline aquifers subjected to transient evaporation. The bulk aerodynamic formulation was adopted to simulate transient evaporation rate at ground surface. Subsurface flow pattern, moisture distribution, and salt migration were quantified. Key factors likely affecting this process, including saturated hydraulic conductivity, capillary drive, air humidity, and surrounding water supply, were examined. The results showed that evaporation induced an upward flow pattern, which led to a high saline plume formed beneath the evaporation zone. In absence of surrounding water supply, as the humidity between the ground surface and air tended to equilibrium, evaporation-induced density gradient generated pore water circulations around the plume edge and caused the salt to migrate downwards with "finger" shapes. It was found that capillary properties and atmospheric condition had significant impacts on subsurface moisture distribution and salt migration in response to the evaporation. Larger capillary fringe and/or lower air humidity would allow evaporation to extract more water from the ground. It would induce a larger and denser saline plume formed beneath the evaporation zone. The results also suggested that the presence of the surrounding water supply (represented as a constant water table herein) could provide a steady evaporation rate at the ground surface; meanwhile, in response to the evaporation, a hydraulic gradient was formed from the water supply boundary, which induced an inclined upper saline plume with greater density far from the supply boundary.

  15. Potential of combined Water Sensitive Urban Design systems for salinity treatment in urban environments.

    Science.gov (United States)

    Kazemi, Fatemeh; Golzarian, Mahmood Reza; Myers, Baden

    2018-03-01

    Water sensitive urban design and similar concepts often recommend a 'treatment train' is employed to improve stormwater quality. In this study, the capability of a combined permeable pavement and bioretention basin was examined with a view to developing a permeable pavement reservoir that can supplement the irrigation needs of a bioretention system in semi-arid climates. Salinity was a key study parameter due to published data on salinity in permeable pavement storage, and the potential to harvest water contaminated with de-icing salts. To conduct experiments, roofwater was collected from a roof in Adelaide, South Australia. Water was amended with NaCl to produce a control runoff (no added salt), a medium (500 mg/l) and a high (1500 mg/l) salinity runoff. Water was then run through the pavement into the storage reservoir and used to irrigate the bioretention system. Samples were collected from the roof, the pavement reservoir and the bioretention system outflow to determine whether significant water quality impacts occurred. Results show that while salinity levels increased significantly as water passed through the pavement and through the bioretention system, the increase was beneficial for irrigation purposes as it was from Ca and Mg ions thus reducing the sodium absorption ratio to levels considered 'good' for irrigation in accordance with several guidelines. Permeable paving increased pH of water and this effect was prominent when the initial salt concentration increased. The study shows that permeable pavements with underlying storage can be used to provide supplementary irrigation for bioretention systems, but high initial salt concentrations may present constraints on beneficial use of stormwater. Copyright © 2017. Published by Elsevier Ltd.

  16. STUDY ON IMPACT OF SALINE WATER INUNDATION ON FRESHWATER AQUACULTURE IN SUNDARBAN USING RISK ANALYSIS TOOLS

    Directory of Open Access Journals (Sweden)

    B.K Chand

    2012-11-01

    Full Text Available The impact of saline water inundation on freshwater aquaculture was evaluated through risk assessment tools. Fishponds in low-lying areas of Sagar and Basanti block are prone to saline water flooding. Respondents of Sagar block considered events like cyclone and coastal flooding as extreme risk; erratic monsoon, storm surge and land erosion as high risk; temperature rise, sea level rise, hot & extended summer and precipitation as medium risk. Likewise, in Basanti block the respondents rated cyclone as extreme risk; erratic monsoon, storm surge as high risk; temperature rise, hot & extended summer, land erosion, and precipitation as medium risk; coastal flooding and sea level rise as low risk. Fish farmers of Sagar block classified the consequences of saline water flooding like breach of pond embankment and mass mortality of fishes as extreme risk; escape of existing fish stock and diseases as high risk; entry of unwanted species, retardation of growth and deterioration of water quality as medium risk; and damage of pond environment as low risk. Farmers of Basanti block categorised breach of pond dyke, mass mortality of fishes and entry of unwanted species as extreme risk; escape of fish and diseases as high risk; retardation of growth as medium risk; deterioration of water quality and damage of pond environment as low risk. To reduce the threats against saline water ingression, farmers are taking some coping measures like increase in pond dyke height; repair and strengthening of dyke; plantation on dyke; dewatering and addition of fresh water; application of chemicals/ lime/ dung; addition of tree branches in pond for hide outs etc.

  17. Carbon dioxide degassing in fresh and saline water I: Degassing performance of a cascade column

    DEFF Research Database (Denmark)

    Moran, Damian

    2010-01-01

    A study was undertaken to measure carbon dioxide degassing in a cascade column operating with both fresh (0‰) and saline water (35‰ NaCl) at 15 °C. The cascade column contained bio-block type packing material, was 1.7 m long in each dimension, and was tested both with and without countercurrent air...... exchange. The CO2 concentration of the influent and effluent water was measured using submersible infrared CO2 probes over an influent range of 10-60 mg L−1 CO2. Carbon dioxide degassing was quantified in terms of the mass transfer coefficient (kLa, log concentration driving force divided by packing height...... to differences in the ionization fractions of inorganic carbon species in the effluent water. The results indicate that CO2 removal will be more problematic for saline or seawater recirculating systems compared to freshwater systems....

  18. The difference of saline and sterile water for tetracycline hydrochloride solvents in cementum demineralization

    Directory of Open Access Journals (Sweden)

    Shinta Ferronika

    2016-12-01

    Full Text Available Background: The root cementum demineralization is an important step in regenerative periodontal therapy to smear layer removal on the root surface. Smear layer on the root surface becomes a barrier of the new attachment between periodontal tissues with the root surface. The use of tetracycline capsules as root surface demineralizing agent cannot be applied directly on the root surface and solvents such as saline or sterile water are needed. Purpose: The aim of this study was to determine differences between sterile water and saline solvent for tetracycline HCl (tetra HCl as a cementum demineralization. Method: In this study the specimens were divided into three groups: a control, tetra HCl dissolved in saline, and tetra HCl dissolved in sterile water. Application using burnishing method for 3 minutes. Samples were dehydrated with ethanol series of 30% to 100%. Results of the root demineralization observed by scanning electron microscopy (SEM. Statistical analysis was performed using the Kruskal-Wallis followed by a Mann-Whitney nonparametric test. Result: Upon statistical analysis showed that the sterile water as a solvent of tetra HCl is more effective in smear layer removal and collagen structure exposure in the cementum. Conclusion: Tetra HCl dissolved in sterile water was found to be the best root cementum demineralization agent.

  19. Gas exchange and photosynthetic pigments in bell pepper irrigated with saline water

    Directory of Open Access Journals (Sweden)

    Hidelblandi F. de Melo

    Full Text Available ABSTRACT The tools that evaluate the salinity effects on plants have great relevance as they contribute to understanding of the mechanisms of tolerance. This study aimed to evaluate gas exchanges and the contents of photosynthetic pigments in bell peppers cultivated with saline solutions (0, 1, 3, 5, 7 and 9 dS m-1 prepared using two sources: NaCl and a mixture of Ca, Mg, K, Na and Cl salts, in randomized blocks with a 6 x 2 factorial scheme and 4 replicates, totaling 48 experimental plots. The net photosynthesis (A, stomatal conductance (gs, transpiration (E, internal CO2 concentration (Ci, instantaneous carboxylation efficiency (A/Ci and water use efficiency (WUE, besides chlorophyll a, b and carotenoids were evaluated. The gas exchange parameters were efficient to indicate the effects of salinity. All photosynthetic pigments decreased with increased electrical conductivity, and the chlorophyll a is the most sensitive to salinity, while the water use efficiency increased with the increment of electrical conductivity.

  20. Temporal dynamics of hot desert microbial communities reveal structural and functional responses to water input

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, Alacia; Valverde, Angel; Ramond, Jean-Baptiste; Makhalanyane, Thulani P.; Jansson, Janet K.; Hopkins, David W.; Aspray, Thomas J.; Seely, Mary; Trindade, Marla I.; Cowan, Don A.

    2016-09-29

    The temporal dynamics of desert soil microbial communities are poorly understood. Given the implications for ecosystem functioning under a global change scenario, a better understanding of desert microbial community stability is crucial. Here, we sampled soils in the central Namib Desert on sixteen different occasions over a one-year period. Using Illumina-based amplicon sequencing of the 16S rRNA gene, we found that α-diversity (richness) was more variable at a given sampling date (spatial variability) than over the course of one year (temporal variability). Community composition remained essentially unchanged across the first 10 months, indicating that spatial sampling might be more important than temporal sampling when assessing β-diversity patterns in desert soils. However, a major shift in microbial community composition was found following a single precipitation event. This shift in composition was associated with a rapid increase in CO2 respiration and productivity, supporting the view that desert soil microbial communities respond rapidly to re-wetting and that this response may be the result of both taxon-specific selection and changes in the availability or accessibility of organic substrates. Recovery to quasi pre-disturbance community composition was achieved within one month after rainfall.

  1. Geology and geochemistry of the Atacama Desert.

    Science.gov (United States)

    Tapia, J; González, R; Townley, B; Oliveros, V; Álvarez, F; Aguilar, G; Menzies, A; Calderón, M

    2018-02-14

    The Atacama Desert, the driest of its kind on Earth, hosts a number of unique geological and geochemical features that make it unlike any other environment on the planet. Considering its location on the western border of South America, between 17 and 28 °S, its climate has been characterized as arid to hyperarid for at least the past 10 million years. Notably dry climatic conditions of the Atacama Desert have been related to uplift of the Andes and are believed to have played an important role in the development of the most distinctive features of this desert, including: (i) nitrates and iodine deposits in the Central Depression, (ii) secondary enrichment in porphyry copper deposits in the Precordillera, (iii) Li enrichment in salt flats of the Altiplano, and (iv) life in extreme habitats. The geology and physiography of the Atacama Desert have been largely shaped by the convergent margin present since the Mesozoic era. The geochemistry of surface materials is related to rock geochemistry (Co, Cr, Fe, Mn, V, and Zn), salt flats, and evaporite compositions in endorheic basins (As, B, and Li), in addition to anthropogenic activities (Cu, Mo, and Pb). The composition of surface water is highly variable, nonetheless in general it presents a circumneutral pH with higher conductivity and total dissolved solids in brines. Major water constituents, with the exception of HCO 3 - , are generally related to the increase of salinity, and despite the fact that trace elements are not well-documented, surface waters of the Atacama Desert are enriched in As, B, and Li when compared to the average respective concentrations in rivers worldwide.

  2. Determining the Threshold Value of Basil Yield Reduction and Evaluation of Water Uptake Models under Salinity Stress Condition

    OpenAIRE

    M. Sarai Tabrizi; H. Babazadeh; M. Homaee; F. Kaveh Kaveh; M. Parsinejad

    2016-01-01

    Introduction: Several mathematical models are being used for assessing the plant response to the salinity of the root zone. The salinity of the soil and water resources is a major challenge for agricultural sector in Iran. Several mathematical models have been developed for plant responses to the salinity stress. However, these models are often applicable in particular conditions. The objectives of this study were to evaluate the threshold value of Basil yield reduction, modeling Basil respon...

  3. IRRIGATION WITH SALINE WATER AND NITROGEN IN PRODUCTION COMPONENTS AND YIELD OF SUNFLOWER

    Directory of Open Access Journals (Sweden)

    JOÃO BATISTA DOS SANTOS

    2016-01-01

    Full Text Available Due to the quantitative and qualitative limitation of water resources, saline water irrigation and nitrogen (N fertilisation can contribute positively to the expansion of sunflower cultivation in the semiarid region of Northeast Brazil. Thus, this study aimed to evaluate production components and yield of sunflower, cv. „Embrapa 122 - V2000‟, irrigated with waters of different salinity levels (electrical conductivity – ECw and fertilised with varying amounts of N in a field experiment in an eutrophic Quartzarenic Neosol from November 2012 to February 2013. The experiment was performed in a completely randomised block design in split plots, in a 5 x 4 factorial scheme, which corresponded to five ECw levels (0.15, 1.5, 2.5, 3.5 and 4.5 dS m - 1 and four N levels (60, 80, 100 and 120 kg ha - 1 , with three replicates and 30 plants per plot. The interaction between water salinity levels and N did not have significant effects on the studied variables; irrigation water salinity had isolated negative effects on the total number of achenes, number of viable achenes, productivity and oil yield of achenes. The increase in N levels stimulated the total number and the number of viable achenes, the mass of 1,000 achenes, capitulum diameter and productivity of achenes of sunflower, cv. „Embrapa 122 - V2000‟, but had no effect on the oil content of achenes. N levels of up to 100 kg ha - 1 promoted adequate oil content in the achenes of sunflower, cv „Embrapa 122 - V2000‟.

  4. Reclamation of highly calcareous saline-sodic soil using low quality water and phosphogypsum

    Science.gov (United States)

    Gharaibeh, M. A.; Rusan, M. J.; Eltaif, N. I.; Shunnar, O. F.

    2014-09-01

    The efficiency of two amendments in reclaiming saline sodic soil using moderately saline (EC) and moderate sodium adsorption ratio (SAR) canal water was investigated. Phosphogypsum (PG) and reagent grade calcium chloride were applied to packed sandy loam soil columns and leached with canal water (SAR = 4, and EC = 2.16 dS m-1). Phosphogypsum was mixed with top soil prior to leaching at application rates of 5, 10, 15, 20, 25, 35, 40 Mg ha-1, whereas calcium chloride was dissolved directly in water at equivalent rates of 4.25, 8.5, 12.75, 17.0, 21.25, 29.75, and 34 Mg ha-1, respectively. Both amendments efficiently reduced soil salinity and sodicity. Calcium chloride removed 90 % of the total Na and soluble salts whereas PG removed 79 and 60 %, respectively. Exchangeable sodium percentage was reduced by 90 % in both amendments. Results indicated that during cation exchange reactions most of the sodium was removed when effluent SAR was at maximum. Phosphogypsum has lower total costs than calcium chloride and as an efficient amendment an application of 30 Mg ha-1 and leaching with 4 pore volume (PV) of canal water could be recommended to reclaim the studied soil.

  5. A new chlorine logging tool: Application in the oilfield development with high salinity formation water

    Energy Technology Data Exchange (ETDEWEB)

    Qing-Yuan, He; Xin-Miao, Hu; Geng-Fei, Wu [China National Petroleum Corp. (China). Jianghan Well Logging Institute; Wen-DA, J. [China National Petroleum Corp. (China). Development Bureau

    1997-10-01

    Radiating formations with isotopes neutron source (Am-Be), and using chlorine element contained in the formation water as a tracer indicator, the chlorine spectrum well logging tool has been regarded as the important and useful tool in the determination of water flooding intensity of formation intervals, especially in the oilfield development stages with high salinity formation water. However, the accuracy of determination of the oil/water-bearings needs to be improved. A new chlorine spectrum logging tool with two detectors has been developed. The short (near) detector uses a He-3 counter tube to measure formation epithermal neutron intensity, the long (far) detector uses a BGO crystal detector to replace traditional Nal detector for measuring the captured X gamma ray spectrum produced by the thermal neutron capture process in the formation. Although the energy resolution of BGO detector to gamma rays is less effective than that of Nal detector, the efficiency of BGO detector to high energy gamma rays is much better. This advantage helps to detect captured chlorine gamma rays, which increases the ability of chlorine element detection. The effect of statistical errors is also reduced. The spectrum autostabilization function in the downhole tool improves the reliability of the whole system. The new chlorine spectrum logging tool can give three log curves simultaneously, these curves are formation porosity, chlorine content, and the ratio of chlorine content and thermal neutron intensity. When formation porosity is larger than 10 p.u, formation water salinity is greater than 40,000 ppm, the resolution to the oil/water-bearings is increased to about 10% compared with the old version tool. Field tests show that the accuracy of water flooding intensity evaluation has been upgraded considerably with the use of new chlorine spectrum logging tool, which contributes greatly to the oilfield development with high salinity formation water 4 refs., 2 tabs., 7 figs.

  6. Benthic communities in inland salinized waters with different salinities and nutrient concentrations and the ecology of Chironomus aprilinus (Diptera: Chironomidae) in the Czech Republic.

    Czech Academy of Sciences Publication Activity Database

    Matěna, Josef; Šímová, I.; Brom, J.; Novotná, K.

    2016-01-01

    Roč. 113, January (2016), s. 122-129 E-ISSN 1802-8829 Institutional support: RVO:60077344 Keywords : Diptera * Chironomidae * Chironomus aprilinus * coal mining * hydric restoration * saline inland waters * fertilization Subject RIV: EH - Ecology, Behaviour Impact factor: 1.167, year: 2016

  7. Power generation from water salinity gradient via osmosis and reverse osmosis

    International Nuclear Information System (INIS)

    Ivanov, Milancho

    2015-01-01

    To reduce dependence on fossil fuels, while at the same time to meet the growing energy demands of the world, it is necessary to explore and promote new alternative energy sources. One such type of renewable energy sources, which recently gained greater credibility is the energy extracted from the water salinity gradient, which is also called blue energy. In this research project will be described a new model of osmotic power plant (MIOS plant), which uses a combination of reverse osmosis and osmosis to convert the energy from the water salinity gradient into electricity. MIOS plant can be built as a vessel anywhere on the surface of the oceans or in the form of dam on the land, which will have a huge advantage over existing plants that can be built only on mouths of rivers. (author)

  8. Impact of Low and Moderate Salinity Water on Plant Performance of Leafy Vegetables in a Recirculating NFT System

    OpenAIRE

    Genhua Niu; Youping Sun; Joseph G. Masabni

    2018-01-01

    Two greenhouse experiments were conducted to examine the growth and mineral nutrition of four leafy vegetables in a nutrient film technique (NFT) system with water with low to moderate salinity. In Expt. 1, a nutrient solution was prepared using reverse osmosis (RO) water and treatments consisted of supplementing with RO water, tap water, or nutrient solution. In Expt. 2, nutrient solution was prepared using three different water sources (treatments), namely, RO water, tap water, or tap water...

  9. Boron removal from saline water by a microbial desalination cell integrated with donnan dialysis

    OpenAIRE

    Ping, Q.; Abu-Reesh, I.M.; He, Z.

    2015-01-01

    Boron has toxic effects on plant growth and thus its removal is necessary from desalinated saline water for irrigation application. Microbial desalination cells (MDCs) are a new approach for effective desalination but boron removal has not been addressed before. Herein, MDCs were studied for boron removal with aid of Donnan Dialysis (DD). The alkaline solution generated by the MDC cathode was used to ionize boric acid to facilitate boron removal. An MDC system with DD pretreatment removed 60 ...

  10. Bronchial hyperreactivity in response to inhalation of ultrasonically nebulised solutions of distilled water and saline.

    OpenAIRE

    Schoeffel, R E; Anderson, S D; Altounyan, R E

    1981-01-01

    To assess non-specific bronchial reactivity the effect of inhaling ultrasonically nebulised solutions of distilled water and hypotonic (0.3%), isotonic (0.9%), and hypertonic (2.7%, 3.6%) saline was investigated in 10 asthmatic patients and nine normal subjects. Expired ventilation and the maximum percentage fall in forced expiratory volume in one second (FEV1) were recorded. The sensitivity to the inhaled solutions was determined by measuring the ventilation required to induce a fall in FEV1...

  11. Forest Clearcutting and Site Preparation on a Saline Soil in East Texas: Impacts on Water Quality

    Science.gov (United States)

    Matthew McBroom; Mingteh Chang; Alexander K. Sayok

    2002-01-01

    Three 0.02 hectare plot-watersheds were installed on a saline soil in the Davy Crockett National Forest near Apple Springs, Texas. Each plot was installed with an H-flume, FW-1 automatic water level recorder, Coshocton N-1 runoff sampler, and two storage tanks. One watershed was undisturbed forested and served a control, one was clearcut without any site-preparation,...

  12. Using microbial desalination cells to reduce water salinity prior to reverse osmosis

    KAUST Repository

    Mehanna, Maha

    2010-01-01

    A microbial desalination cell (MDC) is a new method to reduce the salinity of one solution while generating electrical power from organic matter and bacteria in another (anode) solution. Substantial reductions in the salinity can require much larger volumes of the anode solution than the saline water, but any reduction of salinity will benefit the energy efficiency of a downstream reverse osmosis (RO) desalination system. We investigated here the use of an MDC as an RO pre-treatment method using a new type of air-cathode MDC containing three equally sized chambers. A single cycle of operation using a 1 g L -1 acetate solution reduced the conductivity of salt water (5 g L-1 NaCl) by 43 ± 6%, and produced a maximum power density of 480 mW m-2 with a coulombic efficiency of 68 ± 11%. A higher concentration of acetate (2 g L-1) reduced solution conductivity by 60 ± 7%, and a higher salt concentration (20 g L-1 NaCl) reduced solution conductivity by 50 ± 7%. The use of membranes with increased ion exchange capacities further decreased the solution conductivity by 63 ± 2% (20 g L-1 NaCl). These results demonstrate substantial (43-67%) desalination of water is possible using equal volumes of anode solution and salt water. These results show that MDC treatment could be used to substantially reduce salt concentrations and thus energy demands for downstream RO processing, while at the same time producing electrical power. © 2010 The Royal Society of Chemistry.

  13. The dynamics of Orimulsion in water with varying energy, salinity and temperature

    International Nuclear Information System (INIS)

    Fingas, M.F.; Fieldhouse, B.; Wang, Z.; Environment Canada, Ottawa, ON

    2004-01-01

    Orimulsion is a surfactant-stabilized oil-in-water emulsion composed of 70 per cent bitumen and 30 per cent water. Its unique composition causes it to behave differently from conventional fuel oils when spilled at sea. Earlier studies have shown that Orimulsion is driven by buoyancy to rise in salt water and sink in fresh water. This study conducted 11 experiments at lower temperature and salinity values to obtain new information on the behaviour of Orimulsion in salt, fresh and brackish water. The applied rotational field was adjusted to vary the energy. A time-series of samples of Orimulsion in a 300 litre tank of water were taken to determine depletion rates and characteristics. Oil on the surface was quantified and the concentration of bitumen and particle size distribution was determined. The study also measured changes in bitumen concentration and particle size distribution as a function of time. The data was used to develop simple equations that predict concentrations of bitumen resurfacing and remaining in the water column as a function of time. It was concluded that there is a complex interaction between salinity, time, energy and temperature. 9 refs., 5 tabs., 8 figs

  14. Seed germination and seedling growth of bean (Phaseolus vulgaris as influenced by magnetized saline water

    Directory of Open Access Journals (Sweden)

    Fateme Aghamir

    2016-01-01

    Full Text Available Magnetized water is considered eco-friendly physical presowing seed germination.The aim of this study was to evaluate the effects of magnetized watertreatments on bean (Phaseolus vulgaris germination under saline conditions (0, 25, 50, 75, 100 and 120 mM NaCl. This experiment was performed as factorial in a complete randomized design (CRD with three replications. The results revealed that the roots and shoots length, fresh and dry weight of shoots and roots and roots to shoots ratio, chlorophyll content index, water uptake, tissue water contentwere significantly affected by magnetized water.Irrigation with magnetized water significantly increased the physiologic factors such as germination percentage and index, vigor index and salt tolerance index, compared to untreated control seeds.Mean germination time and parameters T1, T10, T25, T50and T90 (required time for germination of one to 90 percent of seeds were reduced significantly in all magnetized water treated plants in comparison to control.The results also demonstrated that magnetized water was conducive to promote the growth of bean seedlings under saline conditions.

  15. Satellite remote sensing of a low-salinity water plume in the East China Sea

    Directory of Open Access Journals (Sweden)

    Y. H. Ahn

    2008-07-01

    Full Text Available With the aim to map and monitor a low-salinity water (LSW plume in the East China Sea (ECS, we developed more robust and proper regional algorithms from large in-situ measurements of apparent and inherent optical properties (i.e. remote sensing reflectance, Rrs, and absorption coefficient of coloured dissolved organic matter, aCDOM determined in ECS and neighboring waters. Using the above data sets, we derived the following relationships between visible Rrs and absorption by CDOM, i.e. Rrs (412/Rrs (555 vs. aCDOM (400 (m−1 and aCDOM (412 (m−1 with a correlation coefficient R2 0.67 greater than those noted for Rrs (443/Rrs (555 and Rrs (490/Rrs (555 vs. aCDOM (400 (m−1 and aCDOM (412 (m−1. Determination of aCDOM (m−1 at 400 nm and 412 nm is particularly necessary to describe its absorption as a function of wavelength λ using a single exponential model in which the spectral slope S as a proxy for CDOM composition is estimated by the ratio of aCDOM at 412 nm and 400 nm and the reference is explained simply by aCDOM at 412 nm. In order to derive salinity from the absorption coefficient of CDOM, in-situ measurements of salinity made in a wide range of water types from dense oceanic to light estuarine/coastal systems were used along with in-situ measurements of aCDOM at 400 nm, 412 nm, 443 nm and 490 nm. The CDOM absorption at 400 nm was better inversely correlated (R2=0.86 with salinity than at 412 nm, 443 nm and 490 nm (R2=0.85–0.66, and this correlation corresponded best with an exponential (R2=0.98 rather than a linear function of salinity measured in a variety of water types from this and other regions. Validation against a discrete in-situ data set showed that empirical algorithms derived from the above relationships could be successfully applied to satellite data over the range of water types for which they have been developed. Thus, we applied these algorithms to a series of SeaWiFS images for the derivation of CDOM and salinity

  16. Salinity of injection water and its impact on oil recovery absolute permeability, residual oil saturation, interfacial tension and capillary pressure

    Directory of Open Access Journals (Sweden)

    Mehdi Mohammad Salehi

    2017-06-01

    This paper presents laboratory investigation of the effect of salinity injection water on oil recovery, pressure drop, permeability, IFT and relative permeability in water flooding process. The experiments were conducted at the 80 °C and a net overburden pressure of 1700 psi using core sample. The results of this study have been shown oil recovery increases as the injected water salinity up to 200,000 ppm and appointment optimum salinity. This increase has been found to be supported by a decrease in the IFT. This effect caused a reduction in capillary pressure increasing the tendency to reduce the residual oil saturation.

  17. Salinity variations and chemical compositions of waters in the Frio Formation, Texas Gulf Coast. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Morton, R.A.; Garrett, C.M. Jr.; Posey, J.S.; Han, J.H.; Jirik, L.A.

    1981-11-01

    Waters produced from sandstone reservoirs of the deep Frio Formation exhibit spatial variations in chemical composition that roughly coincide with the major tectonic elements (Houston and Rio Grande Embayments, San Marcos Arch) and corresponding depositional systems (Houston and Norias deltas, Greta-Carancahua barrier/strandplain system) that were respectively active along the upper, lower, and middle Texas Coast during Frio deposition. Within an area, salinities are usually depth dependent, and primary trends closely correspond to pore pressure gradients and thermal gradients. Where data are available (mainly in Brazoria County) the increases in TDS and calcium with depth coincide with the zone of albitization, smectite-illite transition, and calcite decrease in shales. Waters have fairly uniform salinities when produced from the same sandstone reservoir within a fault block or adjacent fault blocks with minor displacement. In contrast, stratigraphically equivalent sandstones separated by faults with large displacement usually yield waters with substantially different salinities owing to the markedly different thermal and pressure gradients across the faults that act as barriers to fluid movement.

  18. Spatial and Temporal Distribution of Sea Surface Salinity in Coastal Waters of China Based on Aquarius

    International Nuclear Information System (INIS)

    Wang, Ying; Jiang, Hong; Zhang, Xiuying; Jin, Jiaxin

    2014-01-01

    Sea surface salinity (SSS) is a fundamental parameter for the study of global ocean dynamics, water cycle, and climate variability. Aquarius launched by NASA and the Space Agency of Argentina is a breakthrough which could achieve the remote sensing data of SSS. The present paper takes the coastal of China as study area, which is a representative area of ocean boundary and influenced by continental rivers (Yangtze River and Pearl River). After analyze the temporal and spatial variation of SSS in the coastal of China, the estuary area has obvious low salinity because the injected of freshwater from continent. Take the East China Sea (ECS) and South China Sea (SCS) as representative region to discuss the effect of freshwater to SSS. The salinity is almost equal in winter when the diluted water is inadequate in both rivers. However, an obvious decrease appeared in summer especial July in Yangtze River for abundance discharge inflow the ECS. This is a reasonable expression of Yangtze River discharge is remarkable influence the SSS in coastal area then Pearl River. Survey the distribution range of Yangtze River diluted water (SSS<31psu). The range is small in winter and expands to peak value in summer

  19. Quantification and characterization of putative diazotrophic bacteria from forage palm under saline water irrigation

    Directory of Open Access Journals (Sweden)

    Gabiane dos Reis Antunes

    2017-09-01

    Full Text Available The aim of this study was to evaluate the density and phenotypical diversity of diazotrophic endophytic bacteria from the forage palm irrigated with different saline water depths. Opuntia stricta (IPA-200016 received five depths of saline water (L1: 80%. ETo; L2: 60%.ETo; L3: 40%; ETo; L4: 20%; ETo and, L5: 0% ETo, where ETo is the reference evapotranspiration. The roots were collected in the field, disinfected, grounded and serial diluted from 10-1 to 10-4. The total concentration of diazotrophic bacteria was determined by the most probable number method (MPN and the isolated bacteria were characterized phenotipically. The concentration of bacteria found in forage palm roots ranged from 0.36 x 104 to 109.89 104 cells per gram of root, with highest occurrence on the 60 and 80% ETo. In the dendrogram of similarity it was possible to observe the formation of 24 phenotypic groups with 100% similarity. All bacteria presented similarity superior to 40%. Among these groups, 14 are rare groups, formed by only a single bacterial isolate. In the Semi-Arid conditions, the forage palm that receives the highest amount of saline water, presents a higher density of putative nitrogen-fixing endophytic bacteria with high phenotypic diversity.

  20. Leaf gas exchange in cowpea and CO2 efflux in soil irrigated with saline water

    Directory of Open Access Journals (Sweden)

    Wanderson J. de Oliveira

    Full Text Available ABSTRACT Leaf gas exchanges in plants and soil respiration are important tools for assessing the effects of salinity on the soil-plant system. An experiment was conducted with cowpea irrigated with saline water (0, 2.5, 5.0, 7.5, 10.0 and 12.5 dS m-1 prepared with two sources: NaCl and a mixture of Ca, Mg, Na, K and Cl ions in a randomized block design and a 6 x 2 factorial scheme, with four replicates, totaling 48 experimental plots. At 20 days after planting (DAP, plants were evaluated for net photosynthesis (A, stomatal conductance (gs and transpiration (E using the Infra-Red Gas Analyzer (Model XT6400- LICOR, and water use efficiency, intrinsic water use efficiency and instantaneous efficiency of carboxylation were calculated. At 60 DAP, the soil CO2 efflux (soil respiration was determined with a camera (Model 6400-09- LICOR. Salinity caused reductions in A, gs and E. However, the salt source did not have significant effect on these variables. Soil CO2 efflux was reduced with the increase in the electrical conductivity, especially in the mixture of ions.

  1. EFFECTS OF PLANT SIZE ON PHOTOSYNTHESIS AND WATER RELATIONS IN THE DESERT SHRUB PROSOPIS GLANDULOSA (FABACEAE)

    Science.gov (United States)

    The Jornada del Muerto basin of the Chihuahuan Desert of southern New Mexico, USA, has undergone a marked transition of plant communities. Shrubs such as mesquite (Prosopis glandulosa) have greatly increased or now dominate in areas that were previously dominated by perennial gra...

  2. Leaf water storage increases with salinity and aridity in the mangrove Avicennia marina: integration of leaf structure, osmotic adjustment and access to multiple water sources.

    Science.gov (United States)

    Nguyen, Hoa T; Meir, Patrick; Sack, Lawren; Evans, John R; Oliveira, Rafael S; Ball, Marilyn C

    2017-08-01

    Leaf structure and water relations were studied in a temperate population of Avicennia marina subsp. australasica along a natural salinity gradient [28 to 49 parts per thousand (ppt)] and compared with two subspecies grown naturally in similar soil salinities to those of subsp. australasica but under different climates: subsp. eucalyptifolia (salinity 30 ppt, wet tropics) and subsp. marina (salinity 46 ppt, arid tropics). Leaf thickness, leaf dry mass per area and water content increased with salinity and aridity. Turgor loss point declined with increase in soil salinity, driven mainly by differences in osmotic potential at full turgor. Nevertheless, a high modulus of elasticity (ε) contributed to maintenance of high cell hydration at turgor loss point. Despite similarity among leaves in leaf water storage capacitance, total leaf water storage increased with increasing salinity and aridity. The time that stored water alone could sustain an evaporation rate of 1 mmol m -2  s -1 ranged from 77 to 126 min from subspecies eucalyptifolia to ssp. marina, respectively. Achieving full leaf hydration or turgor would require water from sources other than the roots, emphasizing the importance of multiple water sources to growth and survival of Avicennia marina across gradients in salinity and aridity. © 2017 John Wiley & Sons Ltd.

  3. Improving saline-sodic coalbed natural gas water quality using natural zeolites.

    Science.gov (United States)

    Ganjegunte, Girisha K; Vance, George F; Gregory, Robert W; Urynowicz, Michael A; Surdam, Ronald C

    2011-01-01

    Management of saline-sodic water from the coalbed natural gas (CBNG) industry in the Powder River Basin (PRB) of Wyoming and Montana is a major environmental challenge. Clinoptilolie zeolites mined in Nevada, California, and New Mexico were evaluated for their potential to remove sodium (Na+) from CBNG waters. Based on the exchangeable cation composition, naturally occurring calcium (Ca2+)-rich zeolites from New Mexico were selected for further evaluation. Batch adsorption experiments were conducted to evaluate the potential of the Ca(2+)-rich natural clinoptilolites to remove Na+ from saline-sodic CBNG waters. Batch adsorption experiments indicated that Na+ adsorption capacity ofclinoptilolite ranged from 4.3 (4 x 6 mesh) to 7.98 g kg(-1) (14 x 40 mesh). Among the different adsorption isotherms investigated, the Freundlich Model fitted the data best for smaller-sized (6 x 8, 6 x 14, and 14 x 40 mesh) zeolites. Passing the CBNG water through Ca(2+)-rich zeolite columns reduced the salt content (electrical conductivity [EC]) by 72% with a concurrent reduction in sodium adsorption 10 mmol 1/2 L(-1/2). Zeolite technology appears to be an effective water treatment alternative to industrial membrane treatment for removing Na+ from poor-quality CBNG waters.

  4. Rhizophoraceae Mangrove Saplings Use Hypocotyl and Leaf Water Storage Capacity to Cope with Soil Water Salinity Changes

    Science.gov (United States)

    Lechthaler, Silvia; Robert, Elisabeth M. R.; Tonné, Nathalie; Prusova, Alena; Gerkema, Edo; Van As, Henk; Koedam, Nico; Windt, Carel W.

    2016-01-01

    Some of the most striking features of Rhizophoraceae mangrove saplings are their voluminous cylinder-shaped hypocotyls and thickened leaves. The hypocotyls are known to serve as floats during seed dispersal (hydrochory) and store nutrients that allow the seedling to root and settle. In this study we investigate to what degree the hypocotyls and leaves can serve as water reservoirs once seedlings have settled, helping the plant to buffer the rapid water potential changes that are typical for the mangrove environment. We exposed saplings of two Rhizophoraceae species to three levels of salinity (15, 30, and 0–5‰, in that sequence) while non-invasively monitoring changes in hypocotyl and leaf water content by means of mobile NMR sensors. As a proxy for water content, changes in hypocotyl diameter and leaf thickness were monitored by means of dendrometers. Hypocotyl diameter variations were also monitored in the field on a Rhizophora species. The saplings were able to buffer rapid rhizosphere salinity changes using water stored in hypocotyls and leaves, but the largest water storage capacity was found in the leaves. We conclude that in Rhizophora and Bruguiera the hypocotyl offers the bulk of water buffering capacity during the dispersal phase and directly after settlement when only few leaves are present. As saplings develop more leaves, the significance of the leaves as a water storage organ becomes larger than that of the hypocotyl. PMID:27446125

  5. Rhizophoraceae Mangrove Saplings Use Hypocotyl and Leaf Water Storage Capacity to Cope with Soil Water Salinity Changes.

    Science.gov (United States)

    Lechthaler, Silvia; Robert, Elisabeth M R; Tonné, Nathalie; Prusova, Alena; Gerkema, Edo; Van As, Henk; Koedam, Nico; Windt, Carel W

    2016-01-01

    Some of the most striking features of Rhizophoraceae mangrove saplings are their voluminous cylinder-shaped hypocotyls and thickened leaves. The hypocotyls are known to serve as floats during seed dispersal (hydrochory) and store nutrients that allow the seedling to root and settle. In this study we investigate to what degree the hypocotyls and leaves can serve as water reservoirs once seedlings have settled, helping the plant to buffer the rapid water potential changes that are typical for the mangrove environment. We exposed saplings of two Rhizophoraceae species to three levels of salinity (15, 30, and 0-5‰, in that sequence) while non-invasively monitoring changes in hypocotyl and leaf water content by means of mobile NMR sensors. As a proxy for water content, changes in hypocotyl diameter and leaf thickness were monitored by means of dendrometers. Hypocotyl diameter variations were also monitored in the field on a Rhizophora species. The saplings were able to buffer rapid rhizosphere salinity changes using water stored in hypocotyls and leaves, but the largest water storage capacity was found in the leaves. We conclude that in Rhizophora and Bruguiera the hypocotyl offers the bulk of water buffering capacity during the dispersal phase and directly after settlement when only few leaves are present. As saplings develop more leaves, the significance of the leaves as a water storage organ becomes larger than that of the hypocotyl.

  6. Integral Analysis of Field Work and Laboratory Electrical Resistivity Imaging for Saline Water Intrusion Prediction in Groundwater

    Science.gov (United States)

    Zawawi, M. H.; Zahar, M. F.; Hashim, M. M. M.; Hazreek, Z. A. M.; Zahari, N. M.; Kamaruddin, M. A.

    2018-04-01

    Saline water intrusion is a serious threat to the groundwater as many part of the world utilize groundwater as their main source of fresh water supply. The usage of high salinity level of water as drinking water can lead to a very serious health hazard towards human. Saline water intrusion is a process by which induced flow of seawater into freshwater aquifer along the coastal area. It might happen due to human action and/or by natural event. The climate change and rise up of sea level may speed up the saline water intrusion process. The conventional method for distinguishing and checking saltwater interference to groundwater along the coast aquifers is to gather and test the groundwater from series of observation wells (borehole) with an end goal to give the important information about the hydrochemistry data to conclude whether the water in the well are safe to consume or not. An integrated approach of field and laboratory electrical resistivity investigation is proposed for indicating the contact region between saline and fresh groundwater. It was found that correlation for both soilbox produced almost identical curvilinear trends for 2% increment of seawater tested using sand sample. This project contributes towards predicting the saline water intrusion to the groundwater by non-destructive test that can replaced the conventional method of groundwater monitoring using series of boreholes in the coastal area

  7. Drinking Water Salinity and Raised Blood Pressure: Evidence from a Cohort Study in Coastal Bangladesh.

    Science.gov (United States)

    Scheelbeek, Pauline FD; Chowdhury, Muhammad A H; Haines, Andy; Alam, Dewan S; Hoque, Mohammad A; Butler, Adrian P; Khan, Aneire E; Mojumder, Sontosh K; Blangiardo, Marta A G; Elliott, Paul; Vineis, Paolo

    2017-05-30

    Millions of coastal inhabitants in Southeast Asia have been experiencing increasing sodium concentrations in their drinking-water sources, likely partially due to climate change. High (dietary) sodium intake has convincingly been proven to increase risk of hypertension; it remains unknown, however, whether consumption of sodium in drinking water could have similar effects on health. We present the results of a cohort study in which we assessed the effects of drinking-water sodium (DWS) on blood pressure (BP) in coastal populations in Bangladesh. DWS, BP, and information on personal, lifestyle, and environmental factors were collected from 581 participants. We used generalized linear latent and mixed methods to model the effects of DWS on BP and assessed the associations between changes in DWS and BP when participants experienced changing sodium levels in water, switched from "conventional" ponds or tube wells to alternatives [managed aquifer recharge (MAR) and rainwater harvesting] that aimed to reduce sodium levels, or experienced a combination of these changes. DWS concentrations were highly associated with BP after adjustments for confounding factors. Furthermore, for each 100 mg/L reduction in sodium in drinking water, systolic/diastolic BP was lower on average by 0.95/0.57 mmHg, and odds of hypertension were lower by 14%. However, MAR did not consistently lower sodium levels. DWS is an important source of daily sodium intake in salinity-affected areas and is a risk factor for hypertension. Considering the likely increasing trend in coastal salinity, prompt action is required. Because MAR showed variable effects, alternative technologies for providing reliable, safe, low-sodium fresh water should be developed alongside improvements in MAR and evaluated in "real-life" salinity-affected settings. https://doi.org/10.1289/EHP659.

  8. The effect of process water salinity on flotation of copper ore from Lubin mining region (SW Poland)

    OpenAIRE

    Bakalarz Alicja; Duchnowska Magdalena; Luszczkiewicz Andrzej

    2017-01-01

    The process water used for the flotation of sedimentary copper ore in ore concentration plants in KGHM Polska Miedz S.A. were characterized. The process water used in the flotation circuits is heavily saline. It contains between 25 and 45 g/dm3 of soluble components, and the main constituent, in about 75%, is NaCl. Process water used for flotation consists of reclaimed water from the tailing dam and mine water. The effect of process water salinity on the processes of copper flotation from the...

  9. Evidence for Upward Flow of Saline Water from Depth into the Mississippi River Valley Alluvial Aquifer in Southeastern Arkansas

    Science.gov (United States)

    Larsen, D.; Paul, J.

    2017-12-01

    Groundwater salinization is occurring in the Mississippi River Valley Alluvial (MRVA) aquifer in southeastern Arkansas (SE AR). Water samples from the MRVA aquifer in Chicot and Desha counties have yielded elevated Cl-concentrations with some as high as 1,639 mg/L. Considering that the MRVA aquifer is the principle source of irrigation water for the agricultural economy of SE AR, salinization needs to be addressed to ensure the sustainability of crop, groundwater, and soil resources in the area. The origin of elevated salinity in MRVA aquifer was investigated using spatial and factor analysis of historical water quality data, and sampling and tracer analysis of groundwater from irrigation, municipal, and flowing industrial wells in SE AR. Spatial analysis of Cl- data in relation to soil type, geomorphic features and sand-blow density indicate that the Cl- anomalies are more closely related to the sand-blow density than soil data, suggesting an underlying tectonic control for the distribution of salinity. Factor analysis of historical geochemical data from the MRVA and underlying Sparta aquifer shows dilute and saline groups, with saline groups weighted positively with Cl- or Na+ and Cl-. Tracer data suggest a component of evaporatively evolved crustal water of pre-modern age has mixed with younger, fresher meteoric sources in SE AR to create the saline conditions in the MRVA aquifer. Stable hydrogen and oxygen values of waters sampled from the Tertiary Sparta and MRVA aquifers deviate from the global and local meteoric water lines along an evaporative trend (slope=4.4) and mixing line with Eocene Wilcox Group groundwaters. Ca2+ and Cl- contents vary with Br- along mixing trends between dilute MRVA water and Jurassic Smackover Formation pore fluids in southern AR. Increasing Cl- content with C-14 age in MRVA aquifer groundwater suggests that the older waters are more saline. Helium isotope ratios decrease with He gas content for more saline water, consistent with

  10. Pulmonary epithelial permeability after inhaling saline, distilled water ''fog'' and cold air

    International Nuclear Information System (INIS)

    Borland, C.; Chamberlain, A.; Barber, B.; Higenbottam, T.

    1985-01-01

    It is recognized that hyperventilation of cold air and the inhalation of fine mists of distilled water provoke significant bronchoconstriction in the asthmatic individual, yet little is known as to how these provocations affect the structural integrity of the alveolar epithelial membrane. In 11 normal subjects, the following effects have been studied: cold air hyperventilation for three minutes, inhalation of 80 L of ultrasonically nebulized distilled water ''fog,'' and 80 L of isotonic saline ''fog'' on the half time clearance (T1/2) from the alveoli of technetium 99m diethylene triamine pentaacetate (DTPA), inhaled as an aerosol. The DTPA T1/2 provided a measurement of pulmonary epithelial permeability

  11. The side effects of nitrification inhibitors on leaching water and soil salinization in a field experiment

    Energy Technology Data Exchange (ETDEWEB)

    Diez, J. A.; Arauzo, M.; Hernaiz, P.; Sanz, A.

    2010-07-01

    In experiments carried out in greenhouses, some authors have shown that ammonium sulphate induces greater soil acidity and salinity than other sources of N. Moreover, nitrification inhibitors (NI) tend to cause ammonium to accumulate in soil by retarding its oxidation to nitrate. This accumulated ammonium would also have an effect on soil salinity. Consequently, the aim of this paper was to evaluate the soil and leaching water salinization effects associated with adding NI, dicyandiamide (DCD) and dimethylpyrazole-phosphate (DMPP) to ammonium sulphate nitrate (ASN) fertilizer. This experiment was carried out in the field with an irrigated maize crop. Drainage and Na concentration were measured during both seasons (2006 and 2007) and leached Na was determined. The treatments with NI (DCD and DMPP) were associated with greater Na concentrations in soil solutions and consequently higher rates of Na leaching (in 2007, ASN-DCD 1,292 kg Na ha{sup -}1, ASN-DMPP 1,019 kg Na ha{sup -}1). A treatment involving only ASN also increased the Na concentration in soil and the amount of Na leached in relation to the Control (in 2007, ASN 928 kg Na ha{sup -}1 and Control 587 kg Na ha{sup -}1). The increase in the ammonium concentration in the soil due to the NI treatments could have been the result of the displacement of Na ions from the soil exchange complex through a process which finally led to an increase in soil salinity. Treatments including ammonium fertilizer formulated with NI produced a greater degree of soil salinization due to the presence of ammonium from the fertilizer and accumulated ammonium from the nitrification inhibition. (Author) 31 refs.

  12. Analysing the mechanisms of soil water and vapour transport in the desert vadose zone of the extremely arid region of northern China

    Science.gov (United States)

    Du, Chaoyang; Yu, Jingjie; Wang, Ping; Zhang, Yichi

    2018-03-01

    The transport of water and vapour in the desert vadose zone plays a critical role in the overall water and energy balances of near-surface environments in arid regions. However, field measurements in extremely dry environments face many difficulties and challenges, so few studies have examined water and vapour transport processes in the desert vadose zone. The main objective of this study is to analyse the mechanisms of soil water and vapour transport in the desert vadose zone (depth of ∼350 cm) by using measured and modelled data in an extremely arid environment. The field experiments are implemented in an area of the Gobi desert in northwestern China to measure the soil properties, daily soil moisture and temperature, daily water-table depth and temperature, and daily meteorological records from DOYs (Days of Year) 114-212 in 2014 (growing season). The Hydrus-1D model, which simulates the coupled transport of water, vapour and heat in the vadose zone, is employed to simulate the layered soil moisture and temperature regimes and analyse the transport processes of soil water and vapour. The measured results show that the soil water and temperatures near the land surface have visible daily fluctuations across the entire soil profile. Thermal vapour movement is the most important component of the total water flux and the soil temperature gradient is the major driving factor that affects vapour transport in the desert vadose zone. The most active water and heat exchange occurs in the upper soil layer (depths of 0-25 cm). The matric potential change from the precipitation mainly re-draws the spatio-temporal distribution of the isothermal liquid water in the soil near the land surface. The matric potential has little effect on the isothermal vapour and thermal liquid water flux. These findings offer new insights into the liquid water and vapour movement processes in the extremely arid environment.

  13. Association between polymorphism in the Prolactin I promoter and growth of tilapia in saline-water

    Directory of Open Access Journals (Sweden)

    Ariel Velan

    2015-05-01

    Full Text Available Tilapias are a group of species with a variable tolerance to high salinity, which are cultured worldwide in fresh, brackish and seawater. Prolactin I (PRL I is known as a key hormone in osmoregulatory physiological pathways. A previous study, conducted in a single family, reported on association between polymorphism in a repetitive element within the promoter of the PRL I gene and growth rate of tilapia in saline water. This study was aiming to further validate this association in a larger sample size, and was conducted in nine families over two consecutive breeding seasons. We have confirmed this association in the three F2 families of Oreochromis mossambicus × Oreochromis niloticus hybrids challenged in the first year. The same pattern of improved growth for genotypes with shorter alleles originating from the O. niloticus grand-parental fish, although O. mossambicus is considered to be a more salt tolerant species, was demonstrated. The effects accounted for 13–15% of the phenotypic variance for growth rate (P < 0.05. In the six families from the second spawning season there was no association between the gene polymorphism and the fish growth in saline water. No association was evident between the polymorphism in the PRL I promoter and the expression of the gene.

  14. Determining sources of elevated salinity in pre-hydraulic fracturing water quality data using a multivariate discriminant analysis model

    Science.gov (United States)

    Lautz, L. K.; Hoke, G. D.; Lu, Z.; Siegel, D. I.

    2013-12-01

    Hydraulic fracturing has the potential to introduce saline water into the environment due to migration of deep formation water to shallow aquifers and/or discharge of flowback water to the environment during transport and disposal. It is challenging to definitively identify whether elevated salinity is associated with hydraulic fracturing, in part, due to the real possibility of other anthropogenic sources of salinity in the human-impacted watersheds in which drilling is taking place and some formation water present naturally in shallow groundwater aquifers. We combined new and published chemistry data for private drinking water wells sampled across five southern New York (NY) counties overlying the Marcellus Shale (Broome, Chemung, Chenango, Steuben, and Tioga). Measurements include Cl, Na, Br, I, Ca, Mg, Ba, SO4, and Sr. We compared this baseline groundwater quality data in NY, now under a moratorium on hydraulic fracturing, with published chemistry data for 6 different potential sources of elevated salinity in shallow groundwater, including Appalachian Basin formation water, road salt runoff, septic effluent, landfill leachate, animal waste, and water softeners. A multivariate random number generator was used to create a synthetic, low salinity ( 20 mg/L Cl) as being affected by formation water, road salt, septic effluent, landfill leachate, animal waste, or water softeners. Single elements or pairs of elements (e.g. Cl and Br) were not effective at discriminating between sources of salinity, indicating multivariate methods are needed. The discriminant analysis model classified most accurately samples affected by formation water and landfill leachate, whereas those contaminated by road salt, animal waste, and water softeners were more likely to be discriminated as contaminated by a different source. Using this approach, no shallow groundwater samples from NY appear to be affected by formation water, suggesting the source of salinity pre-hydraulic fracturing is

  15. A risk assessment of water salinization during the initial impounding period of a proposed reservoir in Tianjin, China.

    Science.gov (United States)

    Zhu, Liqin; Jiang, Cuiling; Wang, Youheng; Peng, Yanmei; Zhang, Peng

    2013-09-01

    Water salinization of coastal reservoirs seriously threatens the safety of their water supply. To elucidate the mechanism of salinization and to quantitatively analyze the risk in the initial period of the impoundment of a proposed reservoir in Tianjin Binhai New Area, laboratory and field simulation experiments were implemented and integrated with the actual operation of Beitang Reservoir, which is located in the same region and has been operational for many years. The results suggested that water salinization of the proposed reservoir was mainly governed by soil saline release, evaporation and leakage. Saline release was the prevailing factor in the earlier stage of the impoundment, then the evaporation and leakage effects gradually became notable over time. By referring to the actual case of Beitang Reservoir, it was predicted that the chloride ion (Cl(-)) concentration of the water during the initial impounding period of the proposed reservoir would exceed the standard for quality of drinking water from surface water sources (250 mg L(-1)), and that the proposed reservoir had a high risk of water salinization.

  16. Biological soil crusts in deserts: A short review of their role in soil fertility, stabilization, and water relations

    Science.gov (United States)

    Belnap, Jayne

    2003-01-01

    Cyanobacteria and cyanolichens dominate most desert soil surfaces as the major component of biological soil crusts (BSC). BSCs contribute to soil fertility in many ways. BSC can increase weathering of parent materials by up to 100 times. Soil surface biota are often sticky, and help retain dust falling on the soil surface; this dust provides many plant-essential nutrients including N, P, K, Mg, Na, Mn, Cu, and Fe. BSCs also provide roughened soil surfaces that slow water runoff and aid in retaining seeds and organic matter. They provide inputs of newly-fixed carbon and nitrogen to soils. They are essential in stabilizing soil surfaces by linking soil particles together with filamentous sheaths, enabling soils to resist both water and wind erosion. These same sheaths are important in keeping soil nutrients from becoming bound into plant-unavailable forms. Experimental disturbances applied in US deserts show soil surface impacts decrease N and C inputs from soil biota by up to 100%. The ability to hold aeolian deposits in place is compromised, and underlying soils are exposed to erosion. While most undisturbed sites show little sediment production, disturbance by vehicles or livestock produces up to 36 times more sediment production, with soil movement initiated at wind velocities well below commonly-occurring wind speeds. Winds across disturbed areas can quickly remove this material from the soil surface, thereby potentially removing much of current and future soil fertility. Thus, reduction in the cover of cyanophytes in desert soils can both reduce fertility inputs and accelerate fertility losses.

  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. Assessment of soil salinization risks under irrigation with brackish water in semiarid Tunesia

    NARCIS (Netherlands)

    Bouksila, F.; Bahrib, A.; Berndtsson, R.; Persson, M.; Rozema, J.; Zee, van der 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

  19. Effect of changes in water salinity on ammonium, calcium, dissolved inorganic carbon and influence on water/sediment dynamics

    Science.gov (United States)

    López, P.

    2003-04-01

    The effect of a sudden increase in salinity from 10 to 37 in porewater concentration and the benthic fluxes of ammonium, calcium and dissolved inorganic carbon were studied in sediments of a small coastal lagoon, the Albufera d'Es Grau (Minorca Island, Spain). The temporal effects of the changes in salinity were examined over 17 days using a single diffusion-reaction model and a mass-balance approach. After the salinity change, NH 4+-flux to the water and Ca-flux toward sediments increased (NH 4+-flux: 5000-3000 μmol m -2 d -1 in seawater and 600/250 μmol m -2 d -1 in brackish water; Ca-flux: -40/-76 meq m -2 d -1 at S=37 and -13/-10 meq m -2 d -1 at S=10); however, later NH 4+-flux decreased in seawater, reaching values lower than in brackish water. In contrast, Ca-flux presented similar values in both conditions. The fluxes of dissolved inorganic carbon, which were constant at S=10 (55/45 mmol m -2 d -1), increased during the experiment at S=37 (from ˜30 mmol m -2 d -1 immediately after salinity increase to ˜60 mmol m -2 d -1 after 17 days). In brackish conditions, NH 4+ and Ca 2+ fluxes were consistent with a single diffusion-reaction model that assumes a zero-order reaction for NH 4+ production and a first-order reaction for Ca 2+ production. In seawater, this model explained the Ca-flux observed, but did not account for the high initial flux of NH 4+. The mass balance for 17 days indicated a higher retention of NH 4+ in porewater in the littoral station in seawater conditions (9.5 mmol m -2 at S=37 and 1.6 mmol m -2 at S=10) and a significant reduction in the water consumption at both sites (5 mmol m -2 at S=37; 35/23 mmol m -2 at S=10). In contrast, accumulation of dissolved inorganic carbon in porewater was lower in seawater incubations (-10/-1 meq m -2 at S=37; 50/90 meq m -2 at S=10) and was linked to a higher efflux of CO 2 to the atmosphere, because of calcium carbonate precipitation in water (675/500 meq m -2). These results indicate that increased

  20. Hydrogeochemistry and stable isotopes of ground and surface waters from two adjacent closed basins, Atacama Desert, northern Chile

    Science.gov (United States)

    Alpers, Charles N.; Whittemore, D.O.

    1990-01-01

    The geochemistry and stable isotopes of groundwaters, surface waters, and precipitation indicate different sources of some dissolved constituents, but a common source of recharge and other constituents in two adjacent closed basins in the Atacama Desert region of northern Chile (24??15???-24??45???S). Waters from artesian wells, trenches, and ephemeral streams in the Punta Negra Basin are characterized by concentrations of Na>Ca>Mg and Cl ???SO4, with TDS Mg ??? Ca and SO4 > Cl, with TDS also Mg ??? Ca and SO4 > Cl, but with TDS up to 40 g/l. The deep mine waters have pH between 3.2 and 3.9, and are high in dissolved CO2 (??13 C = -4.8%PDB), indicating probable interaction with oxidizing sulfides. The deep mine waters have ??18O values of ???-1.8%.compared with values < -3.5??? for other Hamburgo Basin waters; thus the mine waters may represent a mixture of meteoric waters with deeper "metamorphic" waters, which had interacted with rocks and exchanged oxygen isotopes at elevated temperatures. Alternatively, the deep mine waters may represent fossil meteoric waters which evolved isotopically along an evaporative trend starting from values quite depleted in ??18O and ??Dd relative to either precipitation or shallow groundwaters. High I/Br ratios in the Hamburgo Basin waters and La Escondida mine waters are consistent with regionally high I in surficial deposits in the Atacama Desert region and may represent dissolution of a wind-blown evaporite component. Rain and snow collected during June 1984, indicate systematic ??18O and ??D fractionation with increasing elevation between 3150 and 4180 m a.s.l. (-0.21??.??18O and -1.7??.??D per 100 m). Excluding the deep mine waters from La Escondida, the waters from the Hamburgo and Punta Negra Basins have similar ??D and ??18O values and together show a distinct evaporative trend (??D = 5.0 ??18O - 20.2). Snowmelt from the central Andes Cordillera to the east is the most likely source of recharge to both basins. Some of the

  1. Variability in the saline water exchange between the Baltic and the Gulf of Gdansk by the sigma-coordinate model

    Directory of Open Access Journals (Sweden)

    Andrzej Jankowski

    2003-03-01

    Full Text Available A three-dimensional baroclinic sigma-coordinate model was applied to study the circulation and thermohaline variabilityin the coastal zone in the south-eastern Baltic Sea. The model is based on the Princeton Ocean Model code of Blumberg & Mellor(1987, known as POM, and has the horizontal resolution of ~5 km and 24 sigma-levels in the vertical. The hydrodynamic conditions and variability of water and salt exchange between the Gulf of Gdansk and the Baltic Proper, and the renewal of water masses in the Gulf of Gdansk due to atmospheric forcing are analyzed. The numerical simulations were performed with real atmospheric forcings as well as with homogeneous (spatially uniform wind fields over the whole Baltic Sea. The numerical simulations showed that the atmospheric forcing (winds can play a significant role in shaping the renewal of bottom saline waters in the Gulf of Gdansk. Two regions of inflow/outflow of saline waters responsible for the salinity regime were located. The overall water exchange between the Gulf and the Baltic Proper as well as the exchange of saline bottom waters appear to be strongly dependent on wind conditions. The net flux of water of salinity >9 PSU is of the order of 48000-100000 m3 s-1. SE, E, S and NE winds were foundto exert the greatest influence on salinity conditions in the Gulf of Gdansk. Estimates of saline (salinity >9 PSU water residencetime based on the model simulation yielded values from 46 days for SE winds to 153 days for NW winds.

  2. Nitrogen Recovered By Sorghum Plants As Affected By Saline Irrigation Water And Organic/Inorganic Resources Using 15N Technique

    International Nuclear Information System (INIS)

    ABOU-ELKHAIR, R.A.; EL-MOHTASEM, M.O.; SOLIMAN, S.M.; GALAL, Y.G.M.; ABD EL-LATIF, E.M.

    2009-01-01

    A pot experiment was conducted in the green house of Soil and Water Department, Nuclear Research Centre, Atomic Energy Authority, Egypt, to follow up the effect of saline irrigation water, inorganic and organic fertilizers on sorghum growth and N fractions that recovered by plant organs. Two types of artificial water salinity were used; one has 3 dS m -1 salinity level with 4 and 8 SAR and the second one has 3 and 6 dS m -1 salinity levels with 6 SAR . Leucenae residue and chicken manure were applied as organic sources at rate of 2% v/v. Sorghum was fertilized with recommended doses of super phosphate and potassium sulfate at rate of 150 kg P and 50 kg K per feddan, respectively. Labelled ammonium sulfate with 5% 15 N atom excess was applied to sorghum at rate of 100 kg N fed -1 . Dry matter yield (stalks and roots) was negatively affected by increasing water salinity levels or SAR ratios. Similar trend was recorded with N uptake by either stalks or roots of sorghum plants. On the other hand, both the dry matter yield and N uptake were positively and significantly affected by incorporation of organic sources in comparison to the untreated control. In this regard, the dry matter yield and N uptake induced by incorporation of chicken manure was superior over those recorded with leucenae residues. It means, in general, that the incorporation of organic sources into the soil may maximize the plant ability to combat the hazards effects caused by irrigation with saline water. Nitrogen derived from fertilizer (% Ndff), soil (% Ndfs) and organic resources (% Ndfr) showed frequent trends as affected by water salinity and organic resources but in most cases, severe reduction of these values was recorded when plants were irrigated with saline water. In the same time, plants were more dependent on N derived from organic sources than those derived from mineral fertilizer. Superiority of one organic source over the other was related to water salinity levels and SAR ratios

  3. Evaluation of Serum for Pathophysiological Effects of Prolonged Low Salinity Water Exposure in Displaced Bottlenose Dolphins (Tursiops truncatus)

    Science.gov (United States)

    Ewing, Ruth Y.; Mase-Guthrie, Blair; McFee, Wayne; Townsend, Forrest; Manire, Charles A.; Walsh, Michael; Borkowski, Rose; Bossart, Gregory D.; Schaefer, Adam M.

    2017-01-01

    We conducted a retrospective study of serum biochemistry and hematologic findings from displaced, out-of-habitat bottlenose dolphins (Tursiops truncatus) exposed to various low salinity environments in waters along the southern United States including southeastern Atlantic and northern Gulf of Mexico. Serum sodium, chloride, and calculated osmolality were significantly lower and below reference ranges in displaced animals compared to free-ranging case control animals. This suggests clinical hyponatremia, hypochloremia, and hypo-osmolality due to an uptake of low saline water from the environment. In addition, significant differences were found in other serum chemistry variables, although none were outside of normal reference ranges for non-controlled free-ranging animals. Multiple linear regressions demonstrated the degree of salinity had a greater pathophysiologic response than the duration of fresh water exposure. The Na/Cl ratio and bicarbonate were the only variables that were significantly modulated by exposure duration. These findings suggest that the degree of salinity is a critical factor when assessing and managing care for dolphins chronically exposed to low salinity water. Results from this study indicate that changes in various biochemical parameters can be used to determine fresh water exposure and aid in determining the treatment for animals recovered from low salinity waters. PMID:28642866

  4. Evaluation of Serum for Pathophysiological Effects of Prolonged Low Salinity Water Exposure in Displaced Bottlenose Dolphins (Tursiops truncatus

    Directory of Open Access Journals (Sweden)

    Ruth Y. Ewing

    2017-06-01

    Full Text Available We conducted a retrospective study of serum biochemistry and hematologic findings from displaced, out-of-habitat bottlenose dolphins (Tursiops truncatus exposed to various low salinity environments in waters along the southern United States including southeastern Atlantic and northern Gulf of Mexico. Serum sodium, chloride, and calculated osmolality were significantly lower and below reference ranges in displaced animals compared to free-ranging case control animals. This suggests clinical hyponatremia, hypochloremia, and hypo-osmolality due to an uptake of low saline water from the environment. In addition, significant differences were found in other serum chemistry variables, although none were outside of normal reference ranges for non-controlled free-ranging animals. Multiple linear regressions demonstrated the degree of salinity had a greater pathophysiologic response than the duration of fresh water exposure. The Na/Cl ratio and bicarbonate were the only variables that were significantly modulated by exposure duration. These findings suggest that the degree of salinity is a critical factor when assessing and managing care for dolphins chronically exposed to low salinity water. Results from this study indicate that changes in various biochemical parameters can be used to determine fresh water exposure and aid in determining the treatment for animals recovered from low salinity waters.

  5. Effects of salinity and soil-drying on radiation use efficiency, water productivity and yield of quinoa (Chenopodium quinoa Willd.)

    DEFF Research Database (Denmark)

    Razzaghi, Fatemeh; Ahmadi, Seyed Hamid; Jacobsen, Sven-Erik

    2012-01-01

    Drought and salinity reduce crop productivity especially in arid and semi-arid regions, and finding a crop which produces yield under these adverse conditions is therefore very important. Quinoa (Chenopodium quinoa Willd.) is such a crop. Hence, a study was conducted in field lysimeters to invest......Drought and salinity reduce crop productivity especially in arid and semi-arid regions, and finding a crop which produces yield under these adverse conditions is therefore very important. Quinoa (Chenopodium quinoa Willd.) is such a crop. Hence, a study was conducted in field lysimeters...... to investigate the effect of salinity and soil–drying on radiation use efficiency, yield and water productivity of quinoa. Quinoa was exposed to five salinity levels (0, 10, 20, 30 and 40 dS m-1) of irrigation water from flower initiation onwards. During the seed-filling phase the five salinity levels were....... Radiation use efficiency of dry matter was similar between salinity levels and between FI and PD. In line with this, no negative effect of severe salinity and soil–drying on total dry matter could be detected. Salinity levels between 20 and 40 dS m-1 significantly reduced the seed yield by ca. 33 % compared...

  6. Are Low Salinity Waters the Remedy to Noctiluca scintillans Blooms in the Arabian Sea?

    Science.gov (United States)

    Gibson, J.

    2017-12-01

    Noctiluca scintillans (Noctiluca) is a mixotrophic, green dinoflagellate that for the past two decades has been producing problematic algal blooms in the Arabian Sea (AS). As a mixotroph, Noctiluca obtains energy from both consumption of phytoplankton as well as its intracellular photosynthesizing endosymbionts named, Pedinomonas noctilucae. It is this autotrophic and heterotrophic dual capability that has largely enabled Noctiluca to be a highly dominant species at the planktonic trophic layer in the AS. Exacerbated by non-point source/point-source pollution in the AS, ocean acidification, and intensified monsoons, Noctiluca currently algal blooms can be as big as three times the size of Texas. By depleting the AS of oxygen, clogging the gills of fish, and altering the AS food web, these algal blooms result in mass fish die offs. In turn this propagates financial and food insecurity issues in countless coastal communities. However, through satellite imaging over the years, it has been observed that the proliferation of Noctiluca is precluded or encounters a "wall" about mid-way along the west coast of India. It is theorized that this "wall" is due to a significant change in salinity. Snow from atop the Himalayan Mountains melts and adds fresh water to the Bay of Bengal (BB), and in winter the East Indian Coastal Current (EICC) carries this fresher water around the southern tip of India and towards the AS. It is believed that this dilution effect impedes the growth of Noctiluca further south. Ultimately, in this study the salinity gradient from the Bay of Bengal (BB) around the horn of India into the AS was replicated in six pairs of culture bottles. Noctiluca was grown in six different salinities including 26, 28, 30, 32, 34, and 38 psu. Algae grown in the 34 and 38 psu bottles, were healthier and 38 psu treated Noctiluca provided optimal conditions for its photosynthesizing endosymbionts. Noctiluca does not grow well at lower salinities, thus applications of low

  7. Saline irrigation water and its effect on N.use efficiency, growth and yield of Sorghum plant using 15N

    International Nuclear Information System (INIS)

    Abd El-Latteef, E.M.

    2010-01-01

    Series of pot experiments were conducted and randomly arranged under greenhouse conditions for evaluating the effect of irrigation with saline water (alternative source) in combination with different organic sources (amendments) i.e. leucaena plant residue (LU), Quail feces (QF) and chicken manure (ChM) added in different percentages against the mineral form (ammonium sulfate) either in ordinary or 15 N labeled (2 and 5% 15 N atom excess) forms, on sorghum growth and nutrients acquisition. Artificial saline water with different EC and SAR values was prepared at laboratory using computer program designed by the author with guiding of the designed Package named Artificial Saline Irrigation Water (ASIW) (Manual of Salinity Research Methods). In addition, proline acid was also sprayed (foliar) on leaves of sorghum plants at different concentrations. The experimental results indicated the positive effect of organic amendments, as compared to mineral fertilizer, and foliar application of proline acid on enhancement of plant growth and nutrient uptake. This phenomenon was pronounced under water salinity conditions. In this regard, increasing of water salinity levels induced reduction in plant growth as well as nutrients acquisition. Data of 14 N/ 15 N ratio analysis pointed out enhancement of N derived from mineral source as affected by organic amendments. At the same time, considerable amounts of N was derived from organic sources and utilized by plants. The superiority of organic sources on each others was fluctuated depending on interaction with water salinity levels and proline concentrations. In conclusion, organic additives and proline acid has an improvement effects especially under adverse condition of irrigation water salinity.

  8. Ecological restoration and recovery in the wind-blown sand hazard areas of northern China: relationship between soil water and carrying capacity for vegetation in the Tengger Desert.

    Science.gov (United States)

    Li, XingRong; Zhang, ZhiShan; Tan, HuiJuan; Gao, YanHong; Liu, LiChao; Wang, XingPing

    2014-05-01

    The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km(2) in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain. Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas. After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert, we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water. The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition. The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession. The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed.

  9. 75 FR 35024 - North Carolina Waters Along the Entire Length of Brunswick and Pender Counties and the Saline...

    Science.gov (United States)

    2010-06-21

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9164-2] North Carolina Waters Along the Entire Length of Brunswick and Pender Counties and the Saline Waters of the Cape Fear River in Brunswick and New Hanover... designation of Brunswick and Pender Counties Coastal Waters as a No Discharge Zone (NDZ). Specifically, these...

  10. Dense intermediate water outflow from the Cretan Sea: A salinity driven, recurrent phenomenon, connected to thermohaline circulation changes

    Science.gov (United States)

    Velaoras, Dimitris; Krokos, George; Nittis, Kostas; Theocharis, Alexander

    2014-08-01

    Data collected from different platforms in the Cretan Sea during the 2000s decade present evidence of gradually increasing salinity in the intermediate and deep intermediate layers after the middle of the decade. The observed gradual salt transport toward the deeper layers indicates contributions of dense water masses formed in various Aegean Sea subbasins. The accumulation of these saline and dense water masses in the Cretan Sea finally led to outflow from both Cretan Straits, with density greater than typical Levantine/Cretan Intermediate water but not dense enough to penetrate into the deep layers of the Eastern Mediterranean. We name this outflowing water mass as dense Cretan Intermediate Water (dCIW). A retrospective analysis of in situ data and literature references during the last four decades shows that similar events have occurred in the past in two occasions: (a) in the 1970s and (b) during the Eastern Mediterranean Transient (EMT) onset (1987-1991). We argue that these salinity-driven Aegean outflows are mostly attributed to recurrent changes of the Eastern Mediterranean upper thermohaline circulation that create favorable dense water formation conditions in the Aegean Sea through salinity preconditioning. We identify these phenomena as "EMT-like" events and argue that in these cases internal thermohaline mechanisms dominate over atmospheric forcing in dense water production. However, intense atmospheric forcing over an already salinity preconditioned basin is indispensable for creating massive deep water outflow from the Cretan Sea, such as the EMT event.

  11. Salinity Assessment, Change, and Impact on Plant Stress / Canopy Water Content (CWC) in Florida Bay using Remote Sensing and GIS

    Science.gov (United States)

    Selch, Donna

    Human activities in the past century have caused a variety of environmental problems in South Florida. In 2000, Congress authorized the Comprehensive Everglades Restoration Plan (CERP), a $10.5-billion mission to restore the South Florida ecosystem. Environmental projects in CERP require salinity monitoring in Florida Bay to provide measures of the effects of restoration on the Everglades ecosystem. However current salinity monitoring cannot cover large areas and is costly, time-consuming, and labor-intensive. The purpose of this dissertation is to model salinity, detect salinity changes, and evaluate the impact of salinity in Florida Bay using remote sensing and geospatial information sciences (GIS) techniques. The specific objectives are to: 1) examine the capability of Landsat multispectral imagery for salinity modeling and monitoring; 2) detect salinity changes by building a series of salinity maps using archived Landsat images; and 3) assess the capability of spectroscopy techniques in characterizing plant stress / canopy water content (CWC) with varying salinity, sea level rise (SLR), and nutrient levels. Geographic weighted regression (GWR) models created using the first three imagery components with atmospheric and sun glint corrections proved to be more correlated (R2 = 0.458) to salinity data versus ordinary least squares (OLS) regression models (R2 = 0.158) and therefore GWR was the ideal regression model for continued Florida Bay salinity assessment. J. roemerianus was also examined to assess the coastal Everglades where salinity modeling is important to the water-land interface. Multivariate greenhouse studies determined the impact of nutrients to be inconsequential but increases in salinity and sea level rise both negatively affected J. roemerianus. Field spectroscopic data was then used to ascertain correlations between CWC and reflectance spectra using spectral indices and derivative analysis. It was determined that established spectral indices (max

  12. Arbuscular mycorrhizal symbiosis alleviates detrimental effects of saline reclaimed water in lettuce plants.

    Science.gov (United States)

    Vicente-Sánchez, J; Nicolás, E; Pedrero, F; Alarcón, J J; Maestre-Valero, J F; Fernández, F

    2014-07-01

    The present study evaluated the effects of inoculation with arbuscular mycorrhizal fungi (AMF; Glomus iranicum var. tenuihypharum sp. nova) on the physiological performance and production of lettuce plants grown under greenhouse conditions and supplied with reclaimed water (RW; urban-treated wastewater with high electrical conductivity; 4.19 dS m(-1)). Four treatments, fresh water, fresh water plus AMF inoculation, RW and RW plus AMF inoculation, were applied and their effects, over time, analyzed. Root mycorrhizal colonization, plant biomass, leaf-ion content, stomatal conductance and net photosynthesis were assessed. Overall, our results highlight the significance of the AMF in alleviation of salt stress and their beneficial effects on plant growth and productivity. Inoculated plants increased the ability to acquire N, Ca, and K from both non-saline and saline media. Moreover, mycorrhization significantly reduced Na plant uptake. Under RW conditions, inoculated plants also showed a better performance of physiological parameters such as net photosynthesis, stomatal conductance and water-use efficiency than non-mycorrhizal plants. Additionally, the high concentration of nutrients already dissolved in reclaimed water suggested that adjustments in the calculation of the fertigation should be conducted by farmers. Finally, this experiment has proved that mycorrhization could be a suitable way to induce salt stress resistance in iceberg lettuce crops as plants supplied with reclaimed water satisfied minimum legal commercial size thresholds. Moreover, the maximum values of Escherichia coli in the reclaimed water were close to but never exceeded the international thresholds established (Spanish Royal Decree 1620/2007; Italian Decree, 2003) and hence lettuces were apt for sale.

  13. Groundwater discharge by evapotranspiration, flow of water in unsaturated soil, and stable isotope water sourcing in areas of sparse vegetation, Amargosa Desert, Nye County, Nevada

    Science.gov (United States)

    Moreo, Michael T.; Andraski, Brian J.; Garcia, C. Amanda

    2017-08-29

    This report documents methodology and results of a study to evaluate groundwater discharge by evapotranspiration (GWET) in sparsely vegetated areas of Amargosa Desert and improve understanding of hydrologic-continuum processes controlling groundwater discharge. Evapotranspiration and GWET rates were computed and characterized at three sites over 2 years using a combination of micrometeorological, unsaturated zone, and stable-isotope measurements. One site (Amargosa Flat Shallow [AFS]) was in a sparse and isolated area of saltgrass (Distichlis spicata) where the depth to groundwater was 3.8 meters (m). The second site (Amargosa Flat Deep [AFD]) was in a sparse cover of predominantly shadscale (Atriplex confertifolia) where the depth to groundwater was 5.3 m. The third site (Amargosa Desert Research Site [ADRS]), selected as a control site where GWET is assumed to be zero, was located in sparse vegetation dominated by creosote bush (Larrea tridentata) where the depth to groundwater was 110 m.Results indicated that capillary rise brought groundwater to within 0.9 m (at AFS) and 3 m (at AFD) of land surface, and that GWET rates were largely controlled by the slow but relatively persistent upward flow of water through the unsaturated zone in response to atmospheric-evaporative demands. Greater GWET at AFS (50 ± 20 millimeters per year [mm/yr]) than at AFD (16 ± 15 mm/yr) corresponded with its shallower depth to the capillary fringe and constantly higher soil-water content. The stable-isotope dataset for hydrogen (δ2H) and oxygen (δ18O) illustrated a broad range of plant-water-uptake scenarios. The AFS saltgrass and AFD shadscale responded to changing environmental conditions and their opportunistic water use included the time- and depth-variable uptake of unsaturated-zone water derived from a combination of groundwater and precipitation. These results can be used to estimate GWET in other areas of Amargosa Desert where hydrologic conditions are similar.

  14. Water subsidies from mountains to deserts: their role in sustaining groundwater-fed oases in a sandy landscape.

    Science.gov (United States)

    Jobbágy, E G; Nosetto, M D; Villagra, P E; Jackson, R B

    2011-04-01

    In arid regions throughout the world, shallow phreatic aquifers feed natural oases of much higher productivity than would be expected solely from local rainfall. In South America, the presence of well-developed Prosopis flexuosa woodlands in the Monte Desert region east of the Andes has puzzled scientists for decades. Today these woodlands provide crucial subsistence to local populations, including descendants of the indigenous Huarpes. We explore the vulnerability and importance of phreatic groundwater for the productivity of the region, comparing the contributions of local rainfall to that of remote mountain recharge that is increasingly being diverted for irrigated agriculture before it reaches the desert. We combined deep soil coring, plant measurements, direct water-table observations, and stable-isotopic analyses (2H and 18O) of meteoric, surface, and ground waters at three study sites across the region, comparing woodland stands, bare dunes, and surrounding shrublands. The isotopic composition of phreatic groundwaters (delta2H: -137 per thousand +/- 5 per thousand) closely matched the signature of water brought to the region by the Mendoza River (-137 per thousand +/- 6 per thousand), suggestin that mountain-river infiltration rather than in situ rainfall deep drainage (-39 per thousand +/- 19 per thousand) was the dominant mechanism of recharge. Similarly, chloride mass balances determined from deep soil profiles (> 6 m) suggested very low recharge rates. Vegetation in woodland ecosystems, where significant groundwater discharge losses, likely >100 mm/yr occurred, relied on regionally derived groundwater located from 6.5 to 9.5 m underground. At these locations, daily water-table fluctuations of 10 mm, and stable-isotopic measurements of plant water, indicated groundwater uptake rates of 200-300 mm/yr. Regional scaling suggests that groundwater evapotranspiration reaches 18-42 mm/yr across the landscape, accounting for 7 17% of the Mendoza River flow

  15. Feasting in fresh water: impacts of food concentration on freshwater tolerance and the evolution of food ? salinity response during the expansion from saline into fresh water habitats

    OpenAIRE

    Lee, Carol Eunmi; Moss, Wynne E; Olson, Nora; Chau, Kevin Fongching; Chang, Yu-Mei; Johnson, Kelsey E

    2013-01-01

    Saline to freshwater invasions have become increasingly common in recent years. A key hypothesis is that rates of freshwater invasions have been amplified in recent years by increased food concentration, yet this hypothesis has remained unexplored. We examined whether elevated food concentration could enhance freshwater tolerance, and whether this effect evolves following saline to freshwater invasions. We examined physiological response to salinity and food concentration in a 2 ? 2 factorial...

  16. Improved method for measuring transparent exopolymer particles (TEP) and their precursors infresh and saline water

    KAUST Repository

    Villacorte, Loreen O.

    2015-03-01

    Transparent exopolymer particles (TEP) and their precursors produced by phyto-/bacterio-planktons in fresh and marine aquatic environments are increasingly considered as a major contributor to organic/particulate and biological fouling in micro-/ultra-filtration and reverse osmosis membrane (RO) systems. However, currently established methods which are based on Alcian blue (AB) staining and spectrophotometric techniques do not measure TEP-precursors and have the tendency to overestimate concentration in brackish/saline water samples due to interference of salinity on AB staining. Here we propose a new semi-quantitative method which allows measurement of both TEP and their colloidal precursors without the interference of salinity. TEP and their precursors are first retained on 10kDa membrane, rinsed with ultra-pure water, and re-suspended in ultra-pure water by sonication and stained with AB, followed by exclusion of TEP-AB precipitates by filtration and absorbance measurement of residual AB. The concentration is then determined based on the reduction of AB absorbance due to reaction with acidic polysaccharides, blank correction and calibration with Xanthan gum standard. The extraction procedure allows concentration of TEP and their pre-cursors which makes it possible to analyse samples with a wide range of concentrations (down to <0.1mg Xeq/L). This was demonstrated through application of the method for monitoring these compounds in algal cultures and a full-scale RO plant. The monitoring also revealed that concentrations of the colloidal precursors were substantially higher than the concentration of TEP themselves. In the RO plant, complete TEP removal was observed over the pre-treatment processes (coagulation-sedimentation-filtration and ultrafiltration) but the TEP precursors were not completely removed, emphasising the importance of measuring this colloidal component to better understand the role of TEP and acidic polysaccharides in RO membrane fouling.

  17. Satellite observations of rainfall effect on sea surface salinity in the waters adjacent to Taiwan

    Science.gov (United States)

    Ho, Chung-Ru; Hsu, Po-Chun; Lin, Chen-Chih; Huang, Shih-Jen

    2017-10-01

    Changes of oceanic salinity are highly related to the variations of evaporation and precipitation. To understand the influence of rainfall on the sea surface salinity (SSS) in the waters adjacent to Taiwan, satellite remote sensing data from the year of 2012 to 2014 are employed in this study. The daily rain rate data obtained from Special Sensor Microwave Imager (SSM/I), Tropical Rainfall Measuring Mission's Microwave Imager (TRMM/TMI), Advanced Microwave Scanning Radiometer (AMSR), and WindSat Polarimetric Radiometer. The SSS data was derived from the measurements of radiometer instruments onboard the Aquarius satellite. The results show the average values of SSS in east of Taiwan, east of Luzon and South China Sea are 33.83 psu, 34.05 psu, and 32.84 psu, respectively, in the condition of daily rain rate higher than 1 mm/hr. In contrast to the rainfall condition, the average values of SSS are 34.07 psu, 34.26 psu, and 33.09 psu in the three areas, respectively at no rain condition (rain rate less than 1 mm/hr). During the cases of heavy rainfall caused by spiral rain bands of typhoon, the SSS is diluted with an average value of -0.78 psu when the average rain rate is higher than 4 mm/hr. However, the SSS was increased after temporarily decreased during the typhoon cases. A possible reason to explain this phenomenon is that the heavy rainfall caused by the spiral rain bands of typhoon may dilute the sea surface water, but the strong winds can uplift the higher salinity of subsurface water to the sea surface.

  18. Responses of the brackish-water amphipod Gammarus duebeni (crustacea) to saline sewage

    Science.gov (United States)

    Jones, M. B.; Johnson, I.

    Soon after the openiing of the Looe sewage treatment works (Cornwall, southwest England) in 1973, it became colonized by the brackish-water amphipod Gammarus duebeni Liljeborg. The works is unusual as it operates with saline sewage and has a tidally-based pattern of salinity fluctuation (S=13 to 34). Various responses of this unique amphipod population (sewage amphipods) have been compared with G. duebeni from the adjacent Looe River estuary (estuarine amphipods) in an attempt to identify long-term responses to sewage. Sewage amphipods were significantly smaller than their estuarine equivalents; the sewage population was biased significantly to males, whereas the sex ratio of the estuarine population significantly favours females. Compared with the estuary, the consistently lower oxygen levels in the works were reflected in significant differences in metabolism. Sewage amphipods maintained high levels of activity under hypoxia ( e.g. swimming), and the higher survival and lower rates of lactic acid accumulation under anoxia than estuarine individuals. In addition, sewage amphipods recovered more rapidly from anoxia and had a lower critical oxygen tension (p c) than estuarine amphipods. Sewage amphipods are exposed to higher levels of heavy metals associated with the domestic sewage and zinc concentrations are particularly elevated in the works. Exposure to elevated zinc concentrations resulted in similar patterns of body zinc uptake for sewage and estuarine Gammarus at high (30) and low (10) salinity, with zinc regulation apparently occuring to an external threshold of 200 γmgZn·dm -3. No consistent interpopulational differences in the effect ofzinc on zinc uptake or on osmoregulation have been identified. However, sewage amphipods had higher survival at all zinc/salinity combinations compared with estuarine individuals. These indicate that sewage amphipods are adapted to the unusual combination of conditions prevailing in the treatment works and, if reproductive

  19. Salinity of deep groundwater in California: Water quantity, quality, and protection.

    Science.gov (United States)

    Kang, Mary; Jackson, Robert B

    2016-07-12

    Deep groundwater aquifers are poorly characterized but could yield important sources of water in California and elsewhere. Deep aquifers have been developed for oil and gas extraction, and this activity has created both valuable data and risks to groundwater quality. Assessing groundwater quantity and quality requires baseline data and a monitoring framework for evaluating impacts. We analyze 938 chemical, geological, and depth data points from 360 oil/gas fields across eight counties in California and depth data from 34,392 oil and gas wells. By expanding previous groundwater volume estimates from depths of 305 m to 3,000 m in California's Central Valley, an important agricultural region with growing groundwater demands, fresh [groundwater volume is almost tripled to 2,700 km(3), most of it found shallower than 1,000 m. The 3,000-m depth zone also provides 3,900 km(3) of fresh and saline water, not previously estimated, that can be categorized as underground sources of drinking water (USDWs; groundwater, especially USDWs. Our findings indicate that California's Central Valley alone has close to three times the volume of fresh groundwater and four times the volume of USDWs than previous estimates suggest. Therefore, efforts to monitor and protect deeper, saline groundwater resources are needed in California and beyond.

  20. Effect of water and saline stress on germination of Atriplex nummularia (Chenopodiaceae)

    International Nuclear Information System (INIS)

    Ruiz, Monica B; Parera, Carlos A

    2013-01-01

    Saline soils, characteristic of arid zones, can affect the germination of the species due to low water potential or ion toxicity. The effect of water and saline stress on germination was evaluated in atriplex nummularia a potential source of forage for arid zones. the seeds were scarified to reduce the inhibitory effect on germination and incubated in at 23 Celsius degrade on germination paper imbibed with solutions of sodium chloride (NaCl) and polyethylene glycol (peg) at three water potentials: -0,5; -1,0 and -1,5 MPA. The percentage germination and germination speed were significantly affected by the concentration of the solution and the solute used. While more negative osmotic potentials, the percentage of germination and germination speed were significantly lower. The seeds germinated in peg solution have higher germination and germination speed than the seeds germinated in NaCl, especially in -1,0 MPA. The data suggest that the seeds of a. nummularia show sensitivity to the presence of Na+ and Cl- ions affecting the germination process.

  1. Do cold, low salinity waters pass through the Indo-Sri Lanka Channel during winter?

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, R.R.; Girishkumar, M.S.; Ravichandran, M.; Gopalakrishna, V.V.; Pankajakshan, T.

    . The SeaWiFS chlorophyll-a data (O’Riley et al., 1998) are also utilized as a tracer to track the southward water flow through the ISLC. The mean monthly (July-August) climatologies of SSS from Simple Ocean Data Assimilation (SODA) analysis (Carton et al...) and the southward flow through the ISLC if any.The SODA which assimilates all available temperature and salinity observations in the world oceans, satellite altimetry, and sea surface temperature (SST) observations to constrain a numerical model of the primitive...

  2. Do cold, low salinity waters pass through the Indo-Sri Lanka Channel during winter?

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, R.R.; Girishkumar, M.S.; Ravichandran, M.; Gopalakrishna, V.V.; Pankajakshan, T.

    the southward water flow through the ISLC. The mean monthly (July–August) Indo-Sri Lanka Channel during winter 7385 climatologies of SSS from simple ocean data assimilation (SODA) analysis (Carton et al. 2005), TMI SST and SeaWiFS chlorophyll-a are utilized... Assimilation (SODA) is an ocean general circulation model-using Parallel Ocean Program with eddy-permitting resolution, which assim- ilates all available hydrographic profile data as well as ocean station data, moored temperature and salinity time series...

  3. Low salinity hydrocarbon water disposal through deep subsurface drip irrigation: leaching of native selenium

    Science.gov (United States)

    Bern, Carleton R.; Engle, Mark A.; Boehlke, Adam R.; Zupancic, John W.; Brown, Adrian; Figueroa, Linda; Wolkersdorfer, Christian

    2013-01-01

    A subsurface drip irrigation system is being used in Wyoming’s Powder River Basin that treats high sodium, low salinity, coal bed methane (CBM) produced water with sulfuric acid and injects it into cropped fields at a depth of 0.92 m. Dissolution of native gypsum releases calcium that combats soil degradation that would otherwise result from high sodium water. Native selenium is leached from soil by application of the CBM water and traces native salt mobilization to groundwater. Resulting selenium concentrations in groundwater at this alluvial site were generally low (0.5–23 μg/L) compared to Wyoming’s agricultural use suitability standard (20 μg/L).

  4. Response of Wheat (Triticum aestivum L. to Irrigation Water Salinity: I. Effect on Agronomic and Yield Attributes

    Directory of Open Access Journals (Sweden)

    S.K. Nadaf

    2001-01-01

    Full Text Available Thirteen salt tolerant wheat genotypes along with local cultivar, WQS 160 were investigated for their response to five levels of irrigation water salinity viz. control (2 dSm-1, 4, 8, 12 and 16 dSm-1 during two winter seasons. The wheat was grown in pots containing sandy loam soil under shade house conditions. The results indicated that the effects of the years, salinity and genotypes were significant to highly significant (p < 0.01 to 0.05 with respect to all the characters studied. Among the interactions, the effect of year x salinity was highly significant (p <0.01 for number of leaves, leaf length, spike exsertion, grain weight, harvest index and dry biomass. Interaction effects of year x genotype were significant to highly significant (p < 0.01 to 0.05 with respect to all the characters except number of leaves while the effect of salinity x genotype was also significant (p < 0.01 for all the characters except plant height and harvest index. Interaction effect of year x salinity x genotype was significant only in case of days to heading initiation (p < 0.01, spike length (p < 0.05 and grain weight/plant (p < 0.01. Adverse effect of salinity was evident in the genotypes for all characters. Salinity tolerance of genotypes was assessed using the concepts of both stress susceptibility index at each higher salinity level in relation to control (lowest salinity level and mean value over the salinity treatments with respect to each character. Among all the genotypes tested, 8-24 and Sids-6 were found to have a consistently high degree of salinity tolerance. These two genotypes were proposed for utilization in breeding program involving local cultivars.

  5. Defining restoration targets for water depth and salinity in wind-dominated Spartina patens (Ait.) Muhl. coastal marshes

    Science.gov (United States)

    Nyman, J.A.; LaPeyre, Megan K.; Caldwell, Andral W.; Piazza, Sarai C.; Thom, C.; Winslow, C.

    2009-01-01

    Coastal wetlands provide valued ecosystem functions but the sustainability of those functions often is threatened by artificial hydrologic conditions. It is widely recognized that increased flooding and salinity can stress emergent plants, but there are few measurements to guide restoration, management, and mitigation. Marsh flooding can be estimated over large areas with few data where winds have little effect on water levels, but quantifying flooding requires hourly measurements over long time periods where tides are wind-dominated such as the northern Gulf of Mexico. Estimating salinity of flood water requires direct daily measurements because coastal marshes are characterized by dynamic salinity gradients. We analyzed 399,772 hourly observations of water depth and 521,561 hourly observations of water salinity from 14 sites in Louisiana coastal marshes dominated by Spartina patens (Ait.) Muhl. Unlike predicted water levels, observed water levels varied monthly and annually. We attributed those observed variations to variations in river runoff and winds. In stable marshes with slow wetland loss rates, we found that marsh elevation averaged 1 cm above mean high water, 15 cm above mean water, and 32 cm above mean low water levels. Water salinity averaged 3.7 ppt during April, May, and June, and 5.4 ppt during July, August, and September. The daily, seasonal, and annual variation in water levels and salinity that were evident would support the contention that such variation be retained when designing and operating coastal wetland management and restoration projects. Our findings might be of interest to scientists, engineers, and managers involved in restoration, management, and restoration in other regions where S. patens or similar species are common but local data are unavailable.

  6. Assessment of the viability of using saline reclaimed water in grapefruit in medium to long term

    Directory of Open Access Journals (Sweden)

    Cristina Romero-Trigueros

    2014-11-01

    Full Text Available Citrus trees are strongly affected by salinity, especially in countries where irrigation is required as a semi-arid Mediterranean agronomic region. The aims of the study were i to identify the best reliable plant-based water status indicator for field grown grapefruit trees irrigated with saline reclaimed water during five years of cultivation by measuring seasonal changes in physiological parameters (i.e. gas exchange and stem water potential measurements, leaf structural traits (i.e. leaf chlorophyll content, area-based leaf nitrogen and area-based dry mass, phytotoxic elements and yield; ii to estimate phytotoxicity thresholds at leaf level. Our results showed that the chlorophyll content was the parameter with the highest number of measures with significant differences (p≤0.05, ANOVA between trees irrigated with reclaimed water and control trees throughout growing stages. Moreover, Chl a increased linearly with area-based leaf nitrogen (R2=0.63; p<0.001 and area-based dry mass (R2=0.64; p<0.001. We also determined the salt-induced phytotoxicity thresholds at which a reduction in yields occurs; these levels were Na: 0.1 g/100 g, Cl: 0.6 g/100 gand B: 100 ppm. In conclusion, we revealed the importance of leaf chlorophyll measurements as a significance diagnostic indicator of salt stress on field grown grapefruit trees. This parameter was also related to plant-based water status indicators such as stem water potential, stomatal conductance and net photosynthesis. Additionally, a salt accumulation potential at leaf level was shown, leading to possible risk in crop sustainability in the medium to long term.

  7. The influence of water/rock − water/clay interactions and mixing in the salinization processes of groundwater

    Directory of Open Access Journals (Sweden)

    Julien Walter

    2017-10-01

    New hydrological insights for the region: The results show that each of the two salinization paths exerts a major and different influence on the chemical signature of groundwater. Groundwater present in the crystalline bedrock naturally evolve from a recharge-type groundwater (Ca-HCO3-dominant to a type of brackish groundwater (Ca-(Na-Cl-dominant due to water/rock interactions (plagioclase weathering and mixing with deep basement fluids. Groundwater evolution in confined aquifers is dominated by water/clay interactions. The term water/clay interactions was introduced in this paper to account for a combination of processes: ion exchange and/or leaching of salt water trapped in the regional aquitard. Mixing with fossil seawater might also increase the groundwater salinity. PCA revealed that Ca2+, Sr2+, Ba2+ are highly correlated with groundwater from bedrock aquifers, while Mg2+, SiO2, K+, SO42−and HCO3− are more representative of the regional confining conditions.

  8. The Effect of Water Table Fluctuation and its Salinity on Fe Crystal and Noncrystal in some Khuzestan Soils

    Directory of Open Access Journals (Sweden)

    mostafa Pajohannia

    2017-01-01

    Full Text Available Introduction: Iron is found in different forms in the soil. In the primary minerals, iron is found as Fe3+ or Fe2+ which converted to Fe2+ and released in unsuitable reduction conditions. Minerals such as sulfide or chlorine and bicarbonate can affect and change the different forms soil Fe. FeAs these elements are abundance in groundwater or soil, they are capable to react chemically with Fe and change different Fe forms and also may deposit or even leach them by increasing its solubility in the soil. Water table fluctuation is a regular phenomenon in Khuzestan that Fe forms change under these situations. The study of Fe oxide forms and its changes can be applied for evaluation of soil development. Therefore, the aim of this study is the water table fluctuation and its quality effects, and some physio-chemical properties on Fe oxides forms in non-saline and saline soils in Khuzestan. Materials and Methods: Soil samples were collected from two regions: saline (Abdolkhan and non-saline (South Susa regions. soil samples were collected from all horizons of 12 soil field studied profiles . The samples were analyzed for soil texture, pH, EC (soil: water ratio 1:5, organic carbon and aggregate stability (Kemper and Rosenau method. Fe forms also were extracted by two methods in all samples: di-tyonite sodium and ammonium oxalate extraction. Fe oxalate extracted was related to Feo (non crystal Fe and Fed-Feo was related to Fec (crystalline Fe. The Fe content were determined by atomic absorbtion spectrophotometer (AAS. Data were analysis in SAS and Excel software and results were presented. Results and Discussion: The results showed that texture were loamy sand to silty clay loam, OM was very poor (0.1-0.7%. The soil salinity was also 2.8-16.8 dS/m. Calcium carbonate equivalent was 38-40%. All pedons were classified in Entisols and Inceptisols according to Keys to soil taxonomy (2010. The results showed that the proportion of Fe with oxalate to di

  9. Partitioning of tetra- and pentabromo diphenyl ether and benzo[a]pyrene among water and dissolved and particulate organic carbon along a salinity gradient in coastal waters.

    Science.gov (United States)

    Kuivikko, Miika; Sorsa, Karoliina; Kukkonen, Jussi V K; Akkanen, Jarkko; Kotiaho, Tapio; Vähätalo, Anssi V

    2010-11-01

    This study assessed the partitioning of 2,2',4,4'-tetrabromo diphenyl ether (BDE-47), 2,2',4,4',5-pentabromo diphenyl ether (BDE-99) and benzo[a]pyrene (BaP) among water, dissolved organic carbon (DOC: 4.93-8.72 mg/L), and particulate organic carbon (POC: 191-462 µg/L) along the salinity gradient (0-5.5‰) of the Baltic Sea off the coast of Finland. Equilibrium dialysis and two solid-phase extraction techniques using polyoxymethylene polymer (POM) were used to determine partitioning coefficients. Experiments using artificial coastal water (ACW) with Nordic fulvic (FAs) and humic acids (HAs) were used to assess the effect of salinity (0 and 5.5‰) on the DOC-water partitioning of the model compounds. All three compounds bound more (2.2-3.8-fold) to the HAs than to the FAs. Increasing salinity from 0 to 5.5‰ decreased sorption to dissolved humic substances in the ACW and Baltic Sea water samples. Along the salinity gradient, the sorption of compounds to organic material decreased when the salinity increased. Particulate organic matter sorbed model compounds per unit of carbon more than dissolved organic matter. Along the studied salinity gradient, the freely dissolved portion increased from 10 to 29% to 52 to 80% in the coastal water samples, mainly because of the increasing salinity and changes in DOC and quality of POC. © 2010 SETAC.

  10. Strategies for safe exploitation of fresh water through multi-strainer skimming wells in saline groundwater areas

    International Nuclear Information System (INIS)

    Alam, M.M.; Jaffery, H.M.; Hanif, M.

    2005-01-01

    Due to growing population of Pakistan, there is a tremendous pressure on our agriculture sector to increase its production to meet the food and fiber requirement. Water is a basic need to increase the agriculture production and to bring more areas under cultivation. The exploitation of groundwater resources is increasing because of limited surface water availability. Statistics indicated that number of public and private tube-wells have increased to more than 5 lacs. Over exploitations of groundwater caused a number of environmental problems including salt water intrusion and increase in the soil and groundwater salinity. A large number of fresh water tube-wells have started pumping saline groundwater in various parts of Pakistan indicating up-coning of saline groundwater in the relatively fresh water aquifers. Use of poor quality groundwater for irrigation is considered as one of the major causes of salinity in the areas of irrigated agriculture. Indiscriminate pumping of the groundwater of marginal quality through skimming fresh water overlain by saline groundwater can not be helpful in the long run. It can add to the root zone salinity and ultimately reduction of crops yield. Mona Reclamation Experimental Project (MREP) is conducting a collaborative research study on 'Root Zone Salinity Management using Fractional Skimming Wells with Pressurized Irrigation' under a research and studies portfolio of the country wide National Drainage Programme (NDP) MREP, IWMI Pakistan and Water Resources Research Institute of PARC are collaborators in this joint research effort. MREP is responsible to specifically address the objective of the study to identify and test a limited number of promising skimming well techniques in the shallow fresh water aquifers which could control the saline water up-coning phenomenon as a consequence of groundwater pumping. Detailed investigations have been done at various locations in the north-central part of Chaj Doab (Sargodha Region) in the

  11. Summer Watering Patterns of Mule Deer in the Great Basin Desert, USA: Implications of Differential Use by Individuals and the Sexes for Management of Water Resources

    Directory of Open Access Journals (Sweden)

    Andrew V. Shields

    2012-01-01

    Full Text Available Changes in the abundance and distribution of free water can negatively influence wildlife in arid regions. Free water is considered a limiting factor for mule deer (Odocoileus hemionus in the Great Basin Desert. Consequently, a better understanding of differential use of water by individuals and the sexes could influence the conservation and management of mule deer and water resources in their habitats. We deployed remote cameras at all known water sources (13 wildlife water developments and 4 springs on one mountain range in western Utah, USA, during summer from 2007 to 2011 to document frequency and timing of water use, number of water sources used by males and females, and to estimate population size from individually identified mule deer. Male and female mule deer used different water sources but visited that resource at similar frequencies. Individual mule deer used few water sources and exhibited high fidelity to that resource. Wildlife water developments were frequently used by both sexes. Our results highlight the differing use of water sources by sexes and individual mule deer. This information will help guide managers when siting and reprovisioning wildlife water developments meant to benefit mule deer and will contribute to the conservation and management of this species.

  12. Effectiveness of inorganic and organic mulching for soil salinity and sodicity control in a grapevine orchard drip-irrigated with moderately saline waters

    Directory of Open Access Journals (Sweden)

    Ramón Aragüés

    2014-05-01

    Full Text Available Soil mulching is a sensible strategy to reduce evaporation, accelerate crop development, reduce erosion and assist in weed control, but its efficiency for soil salinity control is not as well documented. The benefits of inorganic (plastic and organic (grapevine pruning residues mulching for soil salinity and sodicity control were quantified in a grapevine orchard (cultivars ‘Autumn’ Royal and ‘Crimson’ drip-irrigated with moderately saline waters. Soil samples were taken at the beginning and end of the 2008 and 2009 irrigation seasons in six vines of each cultivar and mulching treatment. Soil saturation extract electrical conductivity (ECe, chloride (Cle and sodium adsorption ratio (SARe values increased in all treatments of both grapevines along the irrigation seasons, but the increases were much lower in the mulched than in the bare soils due to reduced evaporation losses and concomitant decreases in salt evapo-concentration. The absolute salinity and sodicity daily increases in ‘Autumn’ and ‘Crimson’ 2008 and in ‘Crimson’ 2009 were on the average 44% lower in the plastic and 76% lower in the organic mulched soils than in the bare soil. The greater efficiency of the organic than the plastic mulch in ‘Crimson’ 2009 was attributed to the leaching of salts by a precipitation of 104 mm that infiltrated the organic mulch but was intercepted by the plastic mulch. Although further work is needed to substantiate these results, the conclusion is that the plastic mulch and, particularly, the organic mulch were more efficient than the bare soil for soil salinity and sodicity control.

  13. Groundwater-surface water interactions in a large semi-arid floodplain: implications for salinity management

    Science.gov (United States)

    Lamontagne, Sébastien; Leaney, Fred W.; Herczeg, Andrew L.

    2005-10-01

    Flow regulation and water diversion for irrigation have considerably impacted the exchange of surface water between the Murray River and its floodplains. However, the way in which river regulation has impacted groundwater-surface water interactions is not completely understood, especially in regards to the salinization and accompanying vegetation dieback currently occurring in many of the floodplains. Groundwater-surface water interactions were studied over a 2 year period in the riparian area of a large floodplain (Hattah-Kulkyne, Victoria) using a combination of piezometric surface monitoring and environmental tracers (Cl-, 2H, and 18O). Despite being located in a local and regional groundwater discharge zone, the Murray River is a losing stream under low flow conditions at Hattah-Kulkyne. The discharge zone for local groundwater, regional groundwater and bank recharge is in the floodplain within 1 km of the river and is probably driven by high rates of transpiration by the riparian Eucalyptus camaldulensis woodland. Environmental tracers data suggest that the origin of groundwater is principally bank recharge in the riparian zone and a combination of diffuse rainfall recharge and localized floodwater recharge elsewhere in the floodplain. Although the Murray River was losing under low flows, bank discharge occurred during some flood recession periods. The way in which the water table responded to changes in river level was a function of the type of stream bank present, with point bars providing a better connection to the alluvial aquifer than the more common clay-lined banks. Understanding the spatial variability in the hydraulic connection with the river channel and in vertical recharge following inundations will be critical to design effective salinity remediation strategies for large semi-arid floodplains.

  14. Impact of water quality and irrigation management on soil salinization in the Drâa valley of Morocco.

    Science.gov (United States)

    Beff, L.; Descamps, C.; Dufey, J.; Bielders, C.

    2009-04-01

    Under the arid climatic conditions of the Drâa valley in southern Morocco, irrigation is essential for crop production. Two sources of water are available to farmers: (1) moderate salinity water from the Oued Drâa (classified as C3-S1 in the USDA irrigation water classification diagram) which is available only a few times per year following discrete releases from the Mansour Eddahbi dam, and (2) high salinity water from wells (C4-S2). Soil salinization is frequently observed, principally on plots irrigated with well water. As Oued water is available in insufficient amounts, strategies must be devised to use well and Oued water judiciously, without inducing severe salinization. The salinization risk under wheat production was evaluated using the HP1 program (Jacques and Šimůnek, 2005) for different combinations of the two main water sources, different irrigation frequencies and irrigation volumes. The soil was a sandy clay loam (topsoil) to sandy loam (40 cm depth). Soil hydrodynamic properties were derived from in situ measurements and lab measurements on undisturbed soil samples. The HP1 model was parameterized for wheat growth and 12 scenarios were run for 10 year periods using local climatic data. Water quality was measured or estimated on the basis of water samples in wells and various Oueds, and the soil chemical properties were determined. Depending on the scenario, soil salinity in the mean root zone increased from less than 1 meq/100g of soil to more than 5 meq/100g of soil over a ten year period. Salt accumulation was more pronounced at 45 cm soil depth, which is half of the maximum rooting depth, and when well water was preferentially used. Maximum crop yield (water transpired / potential water transpired) was achieved for five scenarios but this implied the use of well water to satisfy the crop water requirements. The usual Drâa Valley irrigation scenario, with five, 84 mm dam water applications per year, lead to a 25% yield loss. Adding the amount

  15. Mathematical modelling of surface water-groundwater flow and salinity interactions in the coastal zone

    Science.gov (United States)

    Spanoudaki, Katerina; Kampanis, Nikolaos A.

    2014-05-01

    Coastal areas are the most densely-populated areas in the world. Consequently water demand is high, posing great pressure on fresh water resources. Climatic change and its direct impacts on meteorological variables (e.g. precipitation) and indirect impact on sea level rise, as well as anthropogenic pressures (e.g. groundwater abstraction), are strong drivers causing groundwater salinisation and subsequently affecting coastal wetlands salinity with adverse effects on the corresponding ecosystems. Coastal zones are a difficult hydrologic environment to represent with a mathematical model due to the large number of contributing hydrologic processes and variable-density flow conditions. Simulation of sea level rise and tidal effects on aquifer salinisation and accurate prediction of interactions between coastal waters, groundwater and neighbouring wetlands requires the use of integrated surface water-groundwater models. In the past few decades several computer codes have been developed to simulate coupled surface and groundwater flow. In these numerical models surface water flow is usually described by the 1-D Saint Venant equations (e.g. Swain and Wexler, 1996) or the 2D shallow water equations (e.g. Liang et al., 2007). Further simplified equations, such as the diffusion and kinematic wave approximations to the Saint Venant equations, are also employed for the description of 2D overland flow and 1D stream flow (e.g. Gunduz and Aral, 2005). However, for coastal bays, estuaries and wetlands it is often desirable to solve the 3D shallow water equations to simulate surface water flow. This is the case e.g. for wind-driven flows or density-stratified flows. Furthermore, most integrated models are based on the assumption of constant fluid density and therefore their applicability to coastal regions is questionable. Thus, most of the existing codes are not well-suited to represent surface water-groundwater interactions in coastal areas. To this end, the 3D integrated

  16. Creosote bush (Larrea tridentata) resin increases water demands and reduces energy availability in desert woodrats (Neotoma lepida).

    Science.gov (United States)

    Mangione, Antonio M; Dearing, M Denise; Karasov, William H

    2004-07-01

    Although many plant secondary compounds are known to have serious consequences for herbivores, the costs of processing them are generally unknown. Two potential costs of ingestion and detoxification of secondary compounds are elevation of the minimum drinking water requirement and excretion of energetically expensive metabolites (i.e., glucuronides) in the urine. To address these impacts, we studied the costs of ingestion of resin from creosote bush (Larrea tridentata) on desert woodrats (Neotoma lepida). The following hypotheses were tested: ingestion of creosote resin by woodrats (1) increases minimum water requirement and (2) reduces energy available by increasing fecal and urinary energy losses. We tested the first hypothesis, by measuring the minimum water requirement of woodrats fed a control diet with and without creosote resin. Drinking water was given in decreasing amounts until woodrats could no longer maintain constant body mass. In two separate experiments, the minimum drinking water requirement of woodrats fed resin was higher than that of controls by 18-30% (about 1-1.7 ml/d). We tested several potential mechanisms of increased water loss associated with the increase in water requirement. The rate of fecal water loss was higher in woodrats consuming resin. Neither urinary water nor evaporative water loss was affected by ingestion of resin. Hypothesis 2 was tested by measuring energy fluxes of woodrats consuming control vs. resin-treated diets. Woodrats on a resin diet had higher urinary energy losses and, thus, metabolized a lower proportion of the dietary energy than did woodrats on control diet. Fecal energy excretion was not affected by resin. The excretion of glucuronic acid represented almost half of the energy lost as a consequence of resin ingestion. The increased water requirement and energy losses of woodrats consuming a diet with resin could have notable ecological consequences.

  17. Detecting leaf pulvinar movements on NDVI time series of desert trees: a new approach for water stress detection.

    Science.gov (United States)

    Chávez, Roberto O; Clevers, Jan G P W; Verbesselt, Jan; Naulin, Paulette I; Herold, Martin

    2014-01-01

    Heliotropic leaf movement or leaf 'solar tracking' occurs for a wide variety of plants, including many desert species and some crops. This has an important effect on the canopy spectral reflectance as measured from satellites. For this reason, monitoring systems based on spectral vegetation indices, such as the normalized difference vegetation index (NDVI), should account for heliotropic movements when evaluating the health condition of such species. In the hyper-arid Atacama Desert, Northern Chile, we studied seasonal and diurnal variations of MODIS and Landsat NDVI time series of plantation stands of the endemic species Prosopis tamarugo Phil., subject to different levels of groundwater depletion. As solar irradiation increased during the day and also during the summer, the paraheliotropic leaves of Tamarugo moved to an erectophile position (parallel to the sun rays) making the NDVI signal to drop. This way, Tamarugo stands with no water stress showed a positive NDVI difference between morning and midday (ΔNDVI mo-mi) and between winter and summer (ΔNDVI W-S). In this paper, we showed that the ΔNDVI mo-mi of Tamarugo stands can be detected using MODIS Terra and Aqua images, and the ΔNDVI W-S using Landsat or MODIS Terra images. Because pulvinar movement is triggered by changes in cell turgor, the effects of water stress caused by groundwater depletion can be assessed and monitored using ΔNDVI mo-mi and ΔNDVI W-S. For an 11-year time series without rainfall events, Landsat ΔNDVI W-S of Tamarugo stands showed a positive linear relationship with cumulative groundwater depletion. We conclude that both ΔNDVI mo-mi and ΔNDVI W-S have potential to detect early water stress of paraheliotropic vegetation.

  18. Detecting leaf pulvinar movements on NDVI time series of desert trees: a new approach for water stress detection.

    Directory of Open Access Journals (Sweden)

    Roberto O Chávez

    Full Text Available Heliotropic leaf movement or leaf 'solar tracking' occurs for a wide variety of plants, including many desert species and some crops. This has an important effect on the canopy spectral reflectance as measured from satellites. For this reason, monitoring systems based on spectral vegetation indices, such as the normalized difference vegetation index (NDVI, should account for heliotropic movements when evaluating the health condition of such species. In the hyper-arid Atacama Desert, Northern Chile, we studied seasonal and diurnal variations of MODIS and Landsat NDVI time series of plantation stands of the endemic species Prosopis tamarugo Phil., subject to different levels of groundwater depletion. As solar irradiation increased during the day and also during the summer, the paraheliotropic leaves of Tamarugo moved to an erectophile position (parallel to the sun rays making the NDVI signal to drop. This way, Tamarugo stands with no water stress showed a positive NDVI difference between morning and midday (ΔNDVI mo-mi and between winter and summer (ΔNDVI W-S. In this paper, we showed that the ΔNDVI mo-mi of Tamarugo stands can be detected using MODIS Terra and Aqua images, and the ΔNDVI W-S using Landsat or MODIS Terra images. Because pulvinar movement is triggered by changes in cell turgor, the effects of water stress caused by groundwater depletion can be assessed and monitored using ΔNDVI mo-mi and ΔNDVI W-S. For an 11-year time series without rainfall events, Landsat ΔNDVI W-S of Tamarugo stands showed a positive linear relationship with cumulative groundwater depletion. We conclude that both ΔNDVI mo-mi and ΔNDVI W-S have potential to detect early water stress of paraheliotropic vegetation.

  19. Salinity measurement in water environment with a long period grating based interferometer

    International Nuclear Information System (INIS)

    Possetti, G R C; Kamikawachi, R C; Muller, M; Fabris, J L; Prevedello, C L

    2009-01-01

    In this work, a comparative study of the behaviour of an in-fibre Mach–Zehnder interferometer for salinity measurement in a water solution is presented. The fibre transducer is composed of two nearly identical long period gratings forming an in-series 7.38 cm long device written in the same fibre optic. Two inorganic and one organic salts (NaCl, KCl, NaCOOH) were characterized within the concentration range from 0 to 150 g L −1 . For the long period grating interferometer, the average obtained sensitivities were −6.61, −5.58 and −3.83 pm/(g L −1 ) for the above salts, respectively, or equivalently −40.8, −46.5 and −39.1 nm RIU −1 . Salinity measured by means of fibre refractometry is compared with measurements obtained using an Abbe refractometer as well as via electrical conductivity. For the long period grating refractometer, the best resolutions attained were 1.30, 1.54 and 2.03 g of salt per litre for NaCl, KCl and NaCOOH, respectively, about two times better than the resolutions obtained by the Abbe refractometer. An average thermal sensitivity of 53 pm °C −1 was measured for the grating transducer immersed in water, indicating the need for the thermal correction of the sensor. Resolutions for the same ionic constituent in different salts are also analysed

  20. Nitrogen Nutrition of Sugar Beet as Affected by Water Salinity, Proline Acid and Nitrogen Forms Using 15N Tracer Technique

    International Nuclear Information System (INIS)

    Abdel Aziz, H.A.

    2014-01-01

    A pot experiment was conducted under green house condition using sugar beet as a test crop. Saline water (sea water) was applied at different levels. i.e. fresh water, 4 and 8 dSm -1 . Labelled urea and ammonium sulphate (5% a.e.) were applied at rate of 120 kg N fed -1 . Also; proline amino acid was sprayed at rate of 25, and 50 ppm. Basal recommended doses of P and K were applied. Crop leaves and tuber yield were severely affected by sea water salinity. These parameters were improved by adding proline acid. Effect of proline acid was significantly varied according to rate of addition, water salinity levels and N forms. In this respect, the improvement of leaves and tuber was more pronounced at rate of 50 ppm proline under 8 dSm -1 salinity when plants fertilized with ammonium sulfate. Another picture was drawn with urea, where the improvement was detected at rate of 25 ppm proline, under 4dSm -1 water salinity level. Nitrogen, phosphorus, potassium and sodium uptake by leaves and tuber of sugar beet plants were significantly improved by addition of 50 ppm proline under 4 and /or 8 dSm -1 salinity levels. Nitrogen uptake was higher in tuber and fertilization with urea than those of leaves and ammonium sulfate, respectively. Other nutrients were varied according to N forms and proline levels. Nitrogen use efficiency was enhanced by spraying proline, despite of addition rates, and negatively affected by increasing salinity levels. In this regard, no big significant difference was detected between urea and ammonium sulfat

  1. Natural and human drivers of salinity in reservoirs and their implications in water supply operation through a Decision Support System

    Science.gov (United States)

    Contreras, Eva; Gómez-Beas, Raquel; Linares-Sáez, Antonio

    2016-04-01

    Salt can be a problem when is originally in aquifers or when it dissolves in groundwater and comes to the ground surface or flows into streams. The problem increases in lakes hydraulically connected with aquifers affecting water quality. This issue is even more alarming when water resources are used for urban and irrigation supply and water quantity and quality restrict that water demand. This work shows a data based and physical modeling approach in the Guadalhorce reservoir, located in southern Spain. This water body receives salt contribution from mainly groundwater flow, getting salinity values in the reservoir from 3500 to 5500 μScm-1. Moreover, Guadalhorce reservoir is part of a complex system of reservoirs fed from the Guadalhorce River that supplies all urban, irrigation, tourism, energy and ecology water uses, which makes that implementation and validation of methods and tools for smart water management is required. Meteorological, hydrological and water quality data from several monitoring networks and data sources, with both historical and real time data during a 40-years period, were used to analyze the impact salinity. On the other hand, variables that mainly depend on the dam operation, such as reservoir water level and water outflow, were also analyzed to understand how they affect to salinity in depth and time. Finally surface and groundwater inflows to the reservoir were evaluated through a physically based hydrological model to forecast when the major contributions take place. Reservoir water level and surface and groundwater inflows were found to be the main drivers of salinity in the reservoir. When reservoir water level is high, daily water inflow around 0.4 hm3 causes changes in salinity (both drop and rise) up to 500 μScm-1, but no significant changes are found when water level falls 2-3 m. However the gradual water outflows due to dam operation and consequent decrease in reservoir water levels makes that, after dry periods, salinity

  2. Geochemistry of sediment moisture in the Badain Jaran desert: Implications of recent environmental changes and water-rock interaction

    International Nuclear Information System (INIS)

    Jin, Li; Edmunds, W. Mike; Lu, Zunli; Ma, Jinzhu

    2015-01-01

    Unsaturated zone pore water has the potential to record history of recharge, palaeoenvironment, pollution movement and water-rock interaction as it percolates through and moves towards the water table. In this study, two 6-m cores from the Badain Jaran desert (NW China) were collected to explore this potential using directly extracted moisture. Pore waters in these unsaturated zone sediments (1–5% moisture by wet weight) were directly extracted using immiscible liquid displacement and then analysed for major anions, cations and trace elements. Results show enrichment in pore water chemistry in the top 1–2 m where strong temperature and moisture fluxes occur. The enrichment in cations relative to chloride is primarily due to silicate mineral dissolution during infiltration. High nitrate and low iron concentrations indicate the overall oxidizing environment, which allows the mobility of oxyanions, such as uranium, arsenic and chromium. The trace elements show enrichment in the upper zone of fluctuation where chemical gradients are strong, but with lesser reaction lower in the profile. The calculated groundwater recharge rates using the chloride mass balance are negligible in this arid region between 1.5 and 3.0 mm/year. The modern rainfall infiltration signature contrasts with that of the underlying groundwater body, which has a distant, regional recharge signature. This reconnaissance study demonstrates the potential for a new geochemical approach to studying geochemical processes in the unsaturated sediments in semi-arid environments due to both natural and human influences. The use of directly extracted water, rather than extraction by dilution (elutriation), facilitates an improved understanding of hydrological and geochemical processes in the unsaturated zone and into the capillary fringe at the water table, because it avoids potential chemical changes induced during elutriation. - Highlights: • A new geochemical approach for the unsaturated zone study

  3. Effect of irrigation water salinity and zinc application on yield, yield components and zinc accumulation of wheat

    Directory of Open Access Journals (Sweden)

    mohamad ahmadi

    2009-06-01

    Full Text Available Salinity stress is one of the most important problems of agriculture in crop production in arid and semi arid regions. Under these conditions, in addition to management strategies, proper and adequate nutrition also has an important role in crop improvement. A greenhouse experiment was conducted to study the effect of 4 different irrigation water salinities (blank, 4, 8 and 12 dS m-1, prepared with 1:1 molar ratio of chlorides of calcium and sodium and magnesium sulphate salts. and 5 different zinc applications (0, 10, 20, 30 mg Kg-1 soil and foliar application of salt of zinc sulphate on yield, yield components and zinc concentration of wheat, using a completely randomized design, factorial with three replications. Plant height, spike length, 1000 grain weight, number of grain per spike, grain and straw yield was decreased by Irrigation water salinity. And all of these parameters were improved by zinc application except 1000 grain weight. Zinc absorption and concentration in straw and grain was decreased by Saline water compared to blank. And concentration of zinc significantly was increased in straw and grain by increase zinc application. The results indicated that, zinc application under low to medium salinity conditions improved growth and yield of wheat due to decreasing the impacts salinity.

  4. A geochemical approach for the evaluation of water availability and salinity in closed basins: the Draa Basin, Morocco

    Science.gov (United States)

    Warner, N.; Lgourna, Z.; Boutaleb, S.; Tagma, T.; Vinson, D. S.; Ettayfi, N.; Bouchaou, L.; Vengosh, A.

    2010-12-01

    In the sub-Saharan Draa Basin of southern Morocco, winter snowmelt from the Atlas Mountains is captured in a reservoir, stored, and discharged downstream for irrigation in six oases. The combined imported surface water and shallow groundwater exploitation for sustaining local agriculture is a common practice in many worldwide arid basins.. Like in many basins, the salinization of groundwater in the Draa Basin has become a limiting factor for agricultural development and long-term sustainability. .Since most of the IPCC climate models predict a significant decrease in precipitation in Northern Africa over the next few decades, water shortage and salinization induced from climate change are expected to exacerbate the existing water crisis. Evaluating the sources and mechanisms of this salinization can provide the necessary tools for sustainable water management in the Draa Basin that may be applied to many similarly arid basins. Here we present new geochemical results from 98 shallow groundwater and four surface water samples collected in May 2009 and April 2010. The samples were collected from upstream tributaries to the reservoir, the reservoir, and groundwater from in six oases downstream of the reservoir. The goal of the survey was to identify the sources of salinity using geochemical and isotopic (87Sr/86Sr, δ2H, and δ18O) signatures in the groundwater, which could derive from three possible sources (1) evaporation and recycling of the irrigation water; (2) dissolution of salts that were entrapped in the unsaturated zone; and (3) lateral flow of adjacent groundwater. The data show a large salinity range from fresh water to highly brackish water with total dissolved salts (TDS) exceeding 12,000 mg/L. The salinity increases with downstream flow between successive oases. Br/Cl and B/Cl ratios decrease with TDS, which suggests that the main mechanism of salinization in the Draa Basin is derived salt dissolution in the unsaturated zone and salinization of the

  5. Environmental effects on proline accumulation and water potential in olive leaves (Olea europaea L. CV Chemlali)) under saline water irrigated field conditions

    International Nuclear Information System (INIS)

    Ben Ahmed, C.; Ben Rouina, B.; Boukhris, M.

    2009-01-01

    In arid regions in Tunisia suffering from limited water resources, the olive extension to irrigated lands has led to the urgent use of saline water, the most readily available water in the these areas. Nevertheless, the effects of salt stress on olive tree seem to be reinforced by environmental conditions. The issue of this paper is to determine how does the olive tree respond to environmental stress in the Mediterranean climate under saline water irrigated field conditions with respect to leaf proline concentrations and water Status. (Author)

  6. A new water permeability measurement method for unsaturated tight materials using saline solutions

    International Nuclear Information System (INIS)

    Malinsky, Laurent; Talandier, Jean

    2012-01-01

    Document available in extended abstract form only. Relative water permeability of material in a radioactive waste disposal is a key parameter to simulate and predict saturation state evolution. In this paper we present a new measurement method and the results obtained for Callovo-Oxfordian (Cox) clay-stone, host rock of the underground Andra laboratory at Bure (Meuse/Haute-Marne). Relative water permeability of such a low permeability rock as Cox clay-stone has been measured up to now by an indirect method. It consists in submitting a rock sample to successive relative humidity steps imposed by saline solutions. The transient mass variation during each step and the mass at hydric equilibrium are interpreted generally by using an inverse analysis method. The water relative permeability function of water saturation is derived from water diffusion coefficient evolution and water retention curve. The proposed new method consists in directly measuring the water flux across a flat cylindrical submitted to a relative humidity gradient. Two special cells have been developed. The tightness of the lateral sample surface is insured by crushing a polyurethane ring surrounding the sample set in an aluminium device placed over a Plexiglas vessel filled with a saline solution. One of the cells is designed to allow humidity measurement in the cell. These cells can also be used to measure the relative humidity produced by a saline solution or by an unsaturated material. During a permeability measurement, the cell with the sample to be tested is continuously weighted in a Plexiglas box in which a saline solution imposes a different relative humidity at the upper sample face. The experimental set-up is shown on Figure 1. The mean permeability of the sample is proportional to the rate of mass variation when steady state is reached. The result of one test is shown on Figure 2(a). Twenty four permeability measurements have been performed on four argillite samples of 15 mm in height and

  7. Salinity maxima associated with some sub-surface water masses in the upper layers of the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Varadachari, V.V.R.; Murty, C.S.; Reddy, C.V.G.

    The distribution of some sub-surface water masses in the western bay of Bengal during the south-west monsoon period is presented. Based on the salinity maxima and sigma t values the existence of waters of Persian Gulf and Red Sea origin could...

  8. Jerusalem artichoke (Helianthus tuberosus, L.) maintains high inulin, tuber yield, and antioxidant capacity under moderately-saline irrigation waters

    Science.gov (United States)

    The scarcity of good quality water in semiarid regions of the world is the main limiting factor for increased irrigated agriculture in those regions. Saline water is generally widely available in arid regions at reduced costs, and can be a viable alternative for crop irrigation. However, the literat...

  9. DESERT ECOSYSTEMS: MAPPING, MONITORING & ASSESSMENT USING SATELLITE REMOTE SENSING

    Directory of Open Access Journals (Sweden)

    A. S. Arya

    2012-09-01

    Full Text Available Desert ecosystems are unique but fragile ecosystems , mostly vulnerable to a variety of degradational processes like water erosion, vegetal degradation, salinity, wind erosion , water logging etc. Some researchers consider desertification to be a process of change, while others view it as the end result of a process of change. There is an urgent need to arrest the process of desertification and combat land degradation. Under the auspices of the United Nations Convention to Combat Desertification (UNCCD, Space Applications Centre, Ahmedabad has undertaken the task of mapping, monitoring and assessment of desertification carrying out pilot project in hot and cold desert regions in drylands on 1:50,000 scale followed by systematic Desertification Status Mappaing (DSM of India on 1:500,000 scale.

  10. Water Quality Parameters of the Yaqui Valley's Aquifer in Semiarid Northwest Mexico and Construction of a Proposed Integrated Salinity Index

    Science.gov (United States)

    Cortes-Jimenez, J.; Troyo-Dieguez, E.; Murillo-Amador, B.; Garcia-Hernandez, J.; Garatuza-Payan, J.; Suh Lee, S.

    2006-05-01

    Salination (salinisation or salinization), a geochemical process related to the build up of salts in soil and groundwater, affects the agroecosystems, reduces the quality of soil, and limits the potential uses of ground water. Unplanned utilization of water resources may lead to the salination problems which cause land deterioration; in consequence, salination is one of the main problems related with degradation of irrigated cropland. In the northwest region of Mexico, the Yaqui Valley is the main agricultural area with 250,000 ha of irrigated cropland. In the historical context of the 'Green Revolution', this semiarid valley, where the 'improved variety-based agriculture' episode originated, used to be a productive agricultural district once flourishing with grain fields, but now vast rows of wheat farmland remain unplanted. As the reservoir which had supplied the irrigation water have reached critically low levels, reservoir water had to be pumped up out of diminished storage over the spillway in order to reach the channel that irrigates the valley. Since 1997 there has been a drastic reduction of the water storage in the reservoir system built on the Yaqui River. An option that temporarily solves the water shortage in this reservoir system consists in the development of deep well network by which 350 million cubic meters of ground water are to be extracted each year. Nevertheless, recent studies state that in 93% of these wells, the extracted water is classified as high salinity or very high salinity (C3 and C4). A strategic approach for sustainable soil and water management became necessary to cope with this problem. The objective of this work was to study the spatial distribution of water quality through GIS methods for the determination of a salination risk index (SRI) according to the soil texture, to identify the aquifer zones where there exists water of low quality, and in the same way, the zones with high concentration of sodium, chloride, bicarbonate

  11. Satellite surface salinity maps to determine fresh water fluxes in the Arctic Ocean

    Science.gov (United States)

    Gabarro, Carolina; Estrella, Olmedo; Emelianov, Mikhail; Ballabrera, Joaquim; Turiel, Antonio

    2017-04-01

    Salinity and temperature gradients drive the thermohaline circulation of the oceans, and play a key role in the ocean-atmosphere coupling. The strong and direct interactions between the ocean and the cryosphere (primarily through sea ice and ice shelves) are also a key ingredient of the thermohaline circulation. Recent observational studies have documented changes in upper Arctic Ocean hydrography [1, 2]. The ESA's Soil Moisture and Ocean Salinity (SMOS) mission, launched in 2009, have the objective to measure soil moisture over the continents and sea surface salinity over the oceans [3]. However, SMOS is also making inroads in Cryospheric science, as the measurements of thin ice thickness and sea ice concentration. SMOS carries an innovative L-band (1.4 GHz, or 21-cm wavelength), passive interferometric radiometer (the so-called MIRAS) that measures the electromagnetic radiation emitted by the Earth's surface, at about 50 km spatial resolution wide swath (1200-km), and with a 3-day revisit time at the equator, but more frequently at the poles. Although the SMOS radiometer operating frequency offers almost the maximum sensitivity of the brightness temperature (TB) to sea surface salinity (SSS) variations, such sensitivity is rather low, even lower at cold waters [4]: 90% of ocean SSS values span a range of brightness temperatures of just 5K. This implies that the SMOS SSS retrieval requires a high performance of the MIRAS interferometric radiometer [5]. New algorithms, recently developed at the Barcelona Expert Center (BEC) to improve the quality of SMOS measurements [6], allow for the first time to derive cold-water SSS maps from SMOS data, and to observe the variability of the SSS in the higher north Atlantic and the Arctic Ocean. In this work, we will provide an assessment of the quality of these new SSS Arctic maps, and we will illustrate their potential to monitor the impact on ocean state of the discharges from the main rivers to the Arctic Ocean. Moreover

  12. Ingestive behavior of crossbred Santa Inês sheep fed water with different salinity levels

    Directory of Open Access Journals (Sweden)

    José Helder Andrade de Moura

    2016-04-01

    Full Text Available The objective of the present study was to evaluate the effect of four water salinity levels on the ingestive behavior of non-castrated crossbred Santa Inês sheep. Thirty-two non-castrated crossbred Santa Inês sheep in feedlot, at seven months of age and initial average weight of 21.76±1.25 kg, were used in the experiment. The experimental design was completely randomized, with four treatments and eight replicates. Four concentrations of salts in the water fed to the animals were evaluated: low (640 mg/l; medium (3,188 mg/l; high (5,740 mg/l and very high (8,326 mg/l levels of total dissolved solids (TDS. For the ingestive behaviors, the animals were observed every ten minutes, for 24 hours, to determine the time spent feeding, ruminating and idle. Also, cud chewing and the average number of defecations and urinations and the frequency of water ingestion were determined. The time spent feeding, ruminating and idle were not changed by the salinity levels in the water. Dry matter intake, neutral detergent fiber intake, total chewing time, total cud chews per day, number of daily meals, average duration of each meal and number of defecations per day did not change either. However, feeding and rumination efficiency in grams of DM/h, water intake and number of urinations were linearly affected, whereas the variables rumination efficiency in grams of NDF/h, grams of dry matter per cud, grams of neutral detergent fiber per cud, number of cuds, number of chews per cud and chewing time per cud presented quadratic effect. The different levels of total dissolved solids (640; 3,188; 5,740; and 8.326 mg/l in the water fed to the sheep did not cause alterations in their ingestive behavior. In conclusion, water with up to 8,326 mg TDS/l can be an alternative strategic and seasonal method to water crossbred Santa Ines sheep.

  13. The Ocean deserts:salt budgets of northern subtropical oceans and their

    KAUST Repository

    Carton, Jim

    2011-04-09

    The Ocean deserts: salt budgets of northern subtropical oceans and their relationship to climate variability The high salinity near surface pools of the subtropical oceans are the oceanic deserts, with high levels of evaporation and low levels of precip

  14. Feasting in fresh water: impacts of food concentration on freshwater tolerance and the evolution of food × salinity response during the expansion from saline into fresh water habitats.

    Science.gov (United States)

    Lee, Carol Eunmi; Moss, Wynne E; Olson, Nora; Chau, Kevin Fongching; Chang, Yu-Mei; Johnson, Kelsey E

    2013-06-01

    Saline to freshwater invasions have become increasingly common in recent years. A key hypothesis is that rates of freshwater invasions have been amplified in recent years by increased food concentration, yet this hypothesis has remained unexplored. We examined whether elevated food concentration could enhance freshwater tolerance, and whether this effect evolves following saline to freshwater invasions. We examined physiological response to salinity and food concentration in a 2 × 2 factorial design, using ancestral brackish and freshwater invading populations of the copepod Eurytemora affinis. We found that high food concentration significantly increases low-salinity tolerance. This effect was reduced in the freshwater population, indicating evolution following the freshwater invasion. Thus, ample food could enable freshwater invasions, allowing subsequent evolution of low-salinity tolerance even under food-poor conditions. We also compared effects of food concentration on freshwater survival between two brackish populations from the native range. Impacts of food concentration on freshwater survival differed between the brackish populations, suggesting variation in functional properties affecting their propensity to invade freshwater habitats. The key implication is that high food concentration could profoundly extend range expansions of brackishwater species into freshwater habitats, potentially allowing for condition-specific competition between saline invaders and resident freshwater species.

  15. Focused ground-water recharge in the Amargosa Desert basin: Chapter E in Ground-water recharge in the arid and semiarid southwestern United States (Professional Paper 1703)

    Science.gov (United States)

    Stonestrom, David A.; Prudic, David E.; Walvoord, Michelle Ann; Abraham, Jared D.; Stewart-Deaker, Amy E.; Glancy, Patrick A.; Constantz, Jim; Laczniak, Randell J.; Andraski, Brian J.; Stonestrom, David A.; Constantz, Jim; Ferré, Ty P.A.; Leake, Stanley A.

    2007-01-01

    The Amargosa River is an approximately 300-kilometer long regional drainage connecting the northern highlands on the Nevada Test Site in Nye County, Nev., to the floor of Death Valley in Inyo County, Calif. Streamflow analysis indicates that the Amargosa Desert portion of the river is dry more than 98 percent of the time. Infiltration losses during ephemeral flows of the Amargosa River and Fortymile Wash provide the main sources of ground-water recharge on the desert-basin floor. The primary use of ground water is for irrigated agriculture. The current study examined ground-water recharge from ephemeral flows in the Amargosa River by using streamflow data and environmental tracers. The USGS streamflow-gaging station at Beatty, Nev., provided high-frequency data on base flow and storm runoff entering the basin during water years 1998–2001. Discharge into the basin during the four-year period totaled 3.03 million cubic meters, three quarters of which was base flow. Streambed temperature anomalies indicated the distribution of ephemeral flows and infiltration losses within the basin. Major storms that produced regional flow during the four-year period occurred in February 1998, during a strong El Niño that more than doubled annual precipitation, and in July 1999. The study also quantified recharge beneath undisturbed native vegetation and irrigation return flow beneath irrigated fields. Vertical profiles of water potential and environmental tracers in the unsaturated zone provided estimates of recharge beneath the river channel (0.04–0.09 meter per year) and irrigated fields (0.1–0.5 meter per year). Chloride mass-balance estimates indicate that 12–15 percent of channel infiltration becomes ground-water recharge, together with 9–22 percent of infiltrated irrigation. Profiles of potential and chloride beneath the dominant desert-shrub vegetation suggest that ground-water recharge has been negligible throughout most of the basin since at least the early

  16. Water cycle and salinity dynamics in the mangrove forests of Europa and Juan de Nova Islands, southwest Indian Ocean.

    Science.gov (United States)

    Lambs, Luc; Mangion, Perrine; Mougin, Eric; Fromard, François

    2016-01-30

    The functioning of mangrove forests found on small coralline islands is characterized by limited freshwater inputs. Here, we present data on the water cycling of such systems located on Europa and Juan de Nova Islands, Mozambique Channel. In order to better understand the water cycle and mangrove growth conditions, we have analysed the hydrological and salinity dynamics of the systems by gauge pressure and isotopic tracing (δ18O and δ2H values). Both islands have important seawater intrusion as measured by the water level change and the high salinities in the karstic ponds. Europa Island displays higher salinity stress, with its inner lagoon, but presents a pluri-specific mangrove species formation ranging from shrub to forest stands. No freshwater signal could be detected around the mangrove trees. On Juan de Nova Island, the presence of sand and detrital sediment allows the storage of some amount of rainfall to form a brackish groundwater. The mangrove surface area is very limited with only small mono-specific stands being present in karstic depression. On the drier Europa Island, the salinity of all the water points is equal to or higher than that of the seawater, and on Juan de Nova the groundwater salinity is lower (5 to 20 PSU). This preliminary study shows that the karstic pothole mangroves exist due to the sea connection through the fractured coral and the high tidal dynamics.

  17. Effect of saline irrigation water on gas exchange and proline metabolism in ber (Ziziphus).

    Science.gov (United States)

    Bagdi, D L; Bagri, G K

    2016-09-01

    An experiment was conducted in pots of 25 kg capacity to study the effect of saline irrigation (EC 0,5,10,15 and 20 dSm-1) prepared by mixing NaCl, NaSO4, CaCl and MgCl2 in 3:1 ratio of chloride and sulphate on gas exchange traits, membrane stability, chlorophyll stability index and osmolytic defense mechanism in Ziziphus rotundifolia and Ziziphus nummularia species of Indian jujube (Z.mauritiana). Result showed that net photosynthetic rate (PN), transpiration (e) and stomatal conductance were comparatively lower in Ziziphus nummularia, which further declined with increasing level of saline irrigation water. Chlorophyll stability and membrane stability also declined significantly in salt stress, with higher magnitude in Ziziphus nummularia. The activity of proline anabolic enzymes; Δ1-Pyrrolline-5-carboxylate reductase, Δ1-Pyrrolline-5-carboxylate synthetase and Ornithine-δ-aminotransferase were recorded higher in Ziziphus rotundifolia with decrease in proline dehydrogenase. The sodium content was observed higher in roots of Ziziphus rotundifolia and leaves of Ziziphus nummularia. Therefore, it is suggested that salt tolerance mechanism was more efficiently operative in Ziziphus rotundifolia owing to better management of physiological attributes, osmolytic defense mechanism and restricted translocation of sodium from root to leaves along with larger accumulation of potassium in its leaves.

  18. Pliocene cooling enhanced by flow of low-salinity Bering Sea water to the Arctic Ocean.

    Science.gov (United States)

    Horikawa, Keiji; Martin, Ellen E; Basak, Chandranath; Onodera, Jonaotaro; Seki, Osamu; Sakamoto, Tatsuhiko; Ikehara, Minoru; Sakai, Saburo; Kawamura, Kimitaka

    2015-06-29

    Warming of high northern latitudes in the Pliocene (5.33-2.58 Myr ago) has been linked to the closure of the Central American Seaway and intensification of North Atlantic Deep Water. Subsequent cooling in the late Pliocene may be related to the effects of freshwater input from the Arctic Ocean via the Bering Strait, disrupting North Atlantic Deep Water formation and enhancing sea ice formation. However, the timing of Arctic freshening has not been defined. Here we present neodymium and lead isotope records of detrital sediment from the Bering Sea for the past 4.3 million years. Isotopic data suggest the presence of Alaskan glaciers as far back as 4.2 Myr ago, while diatom and C37:4 alkenone records show a long-term trend towards colder and fresher water in the Bering Sea beginning with the M2 glaciation (3.3 Myr ago). We argue that the introduction of low-salinity Bering Sea water to the Arctic Ocean by 3.3 Myr ago preconditioned the climate system for global cooling.

  19. Determination of Henry's law constants of organochlorine pesticides in deionized and saline water as a function of temperature

    Science.gov (United States)

    Cetin, Banu; Ozer, Serdar; Sofuoglu, Aysun; Odabasi, Mustafa

    The Henry's law constant ( H) is an important parameter that is required to estimate the air-water exchange of semi-volatile organic compounds. Henry's law constants for 17 banned/restricted/currently used organochlorine pesticides (OCPs) were experimentally determined using a gas-stripping technique in deionized and saline water (3%) over a temperature range of 5-35 °C. H values (at 25 °C) ranged between 0.066±0.037 Pa m 3 mol -1 (endosulfan II) and 62.0±24.2 Pa m 3 mol -1 (heptachlor) in deionized water while the range in saline water was 0.28±0.03 Pa m 3 mol -1 ( γ-HCH) and 135.2±31.3 Pa m 3 mol -1 (heptachlor). The increase in dimensionless Henry's law constants ( H') for OCPs over the studied temperature range was between 3 ( γ-HCH)-19 times (chlorpyrifos) and 3 (endosulfan II)-80 times ( trans-nonachlor) in deionized and saline water, respectively. The calculated enthalpies of phase change (Δ HH) were within the ranges previously reported for OCPs and other organic compounds (23.8-100.2 kJ mol -1). The salting-out constant, ks, ranged between 0.04 ( γ-HCH) and 1.80 L mol -1 (endosulfan II) indicating the importance of assessing the H values of OCPs in saline water to accurately determine their partitioning and fate in seawater.

  20. Impact of Pressure and Brine Salinity on Capillary Pressure-Water Saturation Relations in Geological CO2 Sequestration

    Directory of Open Access Journals (Sweden)

    Jongwon Jung

    2016-01-01

    Full Text Available Capillary pressure-water saturation relations are required to explore the CO2/brine flows in deep saline aquifers including storage capacity, relative permeability of CO2/brine, and change to stiffness and volume. The study on capillary pressure-water saturation curves has been conducted through experimentation and theoretical models. The results show that as the pressure increases up to 12 MPa, (1 capillary pressure-water saturation curves shift to lower values at given water saturation, (2 after the drainage process, residual water saturation decreases, and (3 after the imbibition process, capillary CO2 trapping increases. Capillary pressure-water saturation curves above 12 MPa appear to be similar because of relatively constant contact angle and interfacial tension. Also, as brine salinity increases from 1 M to 3 M NaCl, (1 capillary pressure-water saturation curves shift to lower capillary pressure, (2 residual water saturation decreases, and (3 capillary CO2 trapping increases. The results show that pressure and brine salinity have an influence on the capillary pressure-water saturation curves. Also, the scaled capillary CO2 entry pressure considering contact angle and interfacial tension is inconsistent with atmospheric conditions due to the lack of wettability information. Better exploration of wettability alteration is required to predict capillary pressure-water saturation curves at various conditions that are relevant to geological CO2 sequestration.

  1. Soil water regulates the control of photosynthesis on diel hysteresis between soil respiration and temperature in a desert shrubland

    Science.gov (United States)

    Wang, Ben; Zha, Tian Shan; Jia, Xin; Gong, Jin Nan; Bourque, Charles; Feng, Wei; Tian, Yun; Wu, Bin; Qing Zhang, Yu; Peltola, Heli

    2017-09-01

    Explanations for the occurrence of hysteresis (asynchronicity) between diel soil respiration (Rs) and soil temperature (Ts) have evoked both biological and physical mechanisms. The specifics of these explanations, however, tend to vary with the particular ecosystem or biome being investigated. So far, the relative degree of control of biological and physical processes on hysteresis is not clear for drylands. This study examined the seasonal variation in diel hysteresis and its biological control in a desert-shrub ecosystem in northwest (NW) China. The study was based on continuous measurements of Rs, air temperature (Ta), temperature at the soil surface and below (Tsurf and Ts), volumetric soil water content (SWC), and photosynthesis in a dominant desert shrub (i.e., Artemisia ordosica) over an entire year in 2013. Trends in diel Rs were observed to vary with SWC over the growing season (April to October). Diel variations in Rs were more closely associated with variations in Tsurf than with photosynthesis as SWC increased, leading to Rs being in phase with Tsurf, particularly when SWC > 0.08 m3 m-3 (ratio of SWC to soil porosity = 0.26). However, as SWC decreased below 0.08 m3 m-3, diel variations in Rs were more closely related to variations in photosynthesis, leading to pronounced hysteresis between Rs and Tsurf. Incorporating photosynthesis into a Q10-function eliminated 84.2 % of the observed hysteresis, increasing the overall descriptive capability of the function. Our findings highlight a high degree of control by photosynthesis and SWC in regulating seasonal variation in diel hysteresis between Rs and temperature.

  2. New insight into photo-bromination processes in saline surface waters: The case of salicylic acid

    International Nuclear Information System (INIS)

    Tamtam, Fatima; Chiron, Serge

    2012-01-01

    It was shown, through a combination of field and laboratory observations, that salicylic acid can undergo photo-bromination reactions in sunlit saline surface waters. Laboratory-scale experiments revealed that the photochemical yields of 5-bromosalicylic acid and 3,5-dibromosalicylic acid from salicylic acid were always low (in the 4% range at most). However, this might be of concern since these compounds are potential inhibitors of the 20α-hydroxysteroid dehydrogenase enzyme, with potential implications in endocrine disruption processes. At least two mechanisms were involved simultaneously to account for the photo-generation of brominated substances. The first one might involve the formation of reactive brominated radical species (Br·, Br 2 · − ) through hydroxyl radical mediated oxidation of bromide ions. These ions reacted more selectively than hydroxyl radicals with electron-rich organic pollutants such as salicylic acid. The second one might involve the formation of hypobromous acid, through a two electron oxidation of bromine ions by peroxynitrite. This reaction was catalyzed by nitrite, since these ions play a crucial role in the formation of nitric oxide upon photolysis. This nitric oxide further reacts with superoxide radical anions to yield peroxynitrite and by ammonium through the formation of N-bromoamines, probably due to the ability of N-bromoamines to promote the aromatic bromination of phenolic compounds. Field measurements revealed the presence of salicylic acid together with 5-bromosalicylic and 3,5-dibromosalicylic acid in a brackish coastal lagoon, thus confirming the environmental significance of the proposed photochemically induced bromination pathways. -- Highlights: ► Brominated derivatives of salicylic acid were detected in a brackish lagoon. ► A photochemical pathway was hypothesized to account for bromination of salicylic acid. ► Radical bromine species are partly responsible for the bromination process. ► Hypobromous acid

  3. Investigating effects of hypertonic saline solutions on lipid monolayers at the air-water interface

    KAUST Repository

    Nava Ocampo, Maria F.

    2017-05-01

    More than 70,000 people worldwide suffer from cystic fibrosis, a genetic disease characterized by chronic accumulation of mucus in patients’ lungs provoking bacterial infections, and leading to respiratory failure. An employed age-old treatment to prevent the symptoms of the disease is inhalation of hypertonic saline solution, NaCl at concentrations higher than in the human body (~150 mM). This procedure clears the mucus in the lungs, bringing relief to the patient. However, the biophysical mechanisms underlying this process are not entirely clear. We undertook a new experimental approach to understand the effects of sprayed saline solutions on model lung surfactants towards understanding the mechanisms of the treatment. The surface of lungs contains mainly 1,2-Dipalmitol-sn-glycero-3-phosphocoline (DPPC). As previously assumed by others, we considered that monolayer of DPPC at the air-water interface serves as model system for the lungs surface; we employed a Langmuir-Blodgett (LB) trough and PM-IRRAS to measure surface-specific infrared spectra of the surfactant monolayers and effects on the interfacial tensions. We investigated spraying hyper-saline solutions onto surfactant monolayers at the airwater interface in two parts: (i) validation of our methodology and techniques with stearic acid and (ii) experiments with DPPC monolayers at the air-water interface. Remarkably, when micro-droplets of NaCl were sprayed to the monolayer of stearic acid, we observed enhanced organization of the surfactant, interpreted from the intensities of the CH2 peaks in the surface-specific IR spectra. However, our results with DPPC monolayers didn’t show an effect with the salt added as aerosol, possibly indicating that the experimental methodology proposed is not adequate for the phenomena studied. In parallel, we mimicked respiratory mucous by preparing salt solutions containing 1% (wt%) agar and measured effects on their viscosities. Interestingly, we found that NaCl was much

  4. Determination of delta2H and delta18O in saline oil-associated waters: the question of simple vacuum distillation of water samples prior to isotopic analyses.

    Science.gov (United States)

    Porowski, Adam; Kowski, Peter

    2008-06-01

    The paper deals with analytical and procedural aspects of delta18O and delta2H determination in saline oil-associated waters. The main objective of the study was to show experimentally the qualitative and quantitative applicability of the simple vacuum distillation of saline oil-associated waters while routine procedures of water isotopic analyses are applied. Additionally, two standard off-line techniques of delta2H determination in water - the zinc and the chromium method - have been compared. Each time a typical isotope salt effect has been tracked on the Dead Sea water. The results clearly show that application of the simple vacuum distillation improve the accuracy and reproducibility of delta2H determinations, especially in chromium off-line technique which appeared to be more sensitive to water salinity. The simple vacuum distillation does not improve the quality of delta18O determinations in the range of water salinities studied. Its application to high concentrated brines (for example, Dead Sea water) decreases the time of equilibration but still propagate the isotopic error connected with low water activity (in the case of 18O/16O ratio) and the incomplete water extraction from the remaining salts (in the case of 2H/1H ratio); in consequence, its time-consuming application seems to be baseless.

  5. Physiological and biochemical responses to the exogenous application of proline of tomato plants irrigated with saline water

    Directory of Open Access Journals (Sweden)

    B. Kahlaoui

    2018-01-01

    Full Text Available In scope of crop salinity tolerance, an experiment was carried out in a field using saline water (6.57 dS m−1 and subsurface drip irrigation (SDI on two tomato cultivars (Solanum lycopersicum, cv. Rio Grande and Heinz-2274 in a salty clay soil. Exogenous application of proline was done by foliar spray at two concentrations: 10 and 20 mg L−1, with a control (saline water without proline, during the flowering stage. Significant higher increases in proline and total soluble protein contents, glutamine synthetase (GS, EC6.3.1.2 activities and decreases in proline oxidase (l-proline: O2 Oxidoreductase, EC1.4.3.1 activities were detected in both tomato cultivars when irrigated with saline water (6.57 dS m−1 and exogenously applied by the lower concentration of proline. Taking in consideration the obtained results, it was concluded that the foliar spray of low concentration of proline can increase the tolerance of both cultivars of tomato to salinity under field conditions.

  6. Crop and irrigation management strategies for saline-sodic soils and waters aimed at environmentally sustainable agriculture.

    Science.gov (United States)

    Qadir, M; Oster, J D

    2004-05-05

    Irrigation has long played a key role in feeding the expanding world population and is expected to play a still greater role in the future. As supplies of good-quality irrigation water are expected to decrease in several regions due to increased municipal-industrial-agricultural competition, available freshwater supplies need to be used more efficiently. In addition, reliance on the use and reuse of saline and/or sodic drainage waters, generated by irrigated agriculture, seems inevitable for irrigation. The same applies to salt-affected soils, which occupy more than 20% of the irrigated lands, and warrant attention for efficient, inexpensive and environmentally acceptable management. Technologically and from a management perspective, a couple of strategies have shown the potential to improve crop production under irrigated agriculture while minimizing the adverse environmental impacts. The first strategy, vegetative bioremediation--a plant-assisted reclamation approach--relies on growing appropriate plant species that can tolerate ambient soil salinity and sodicity levels during reclamation of salt-affected soils. A variety of plant species of agricultural significance have been found to be effective in sustainable reclamation of calcareous and moderately sodic and saline-sodic soils. The second strategy fosters dedicating soils to crop production systems where saline and/or sodic waters predominate and their disposal options are limited. Production systems based on salt-tolerant plant species using drainage waters may be sustainable with the potential of transforming such waters from an environmental burden into an economic asset. Such a strategy would encourage the disposal of drainage waters within the irrigated regions where they are generated rather than exporting these waters to other regions via discharge into main irrigation canals, local streams, or rivers. Being economically and environmentally sustainable, these strategies could be the key to future

  7. Developmental and acclimatory contributions to water loss in a desert rodent: investigating the time course of adaptive change.

    Science.gov (United States)

    Tracy, R L; Walsberg, G E

    2001-11-01

    Understanding the evolution of physiological traits requires considering three nonexclusive mechanisms that underlie phenotypes and cause their change over different time scales: acclimation, developmental plasticity, and natural selection for genetically fixed traits. Physiological adjustments to changes in the desiccating potential of the environment were investigated with one subspecies of common desert rodent, Dipodomys merriami merriami (Merriam's kangaroo rat). We raised young whose parents originated from environments that differ in both temperature and humidity. These young were raised under either desiccating or water-abundant conditions, and their water loss was measured at a series of temperatures to determine the effect developmental conditions have on resistance to desiccation. We then determined the contribution of acclimation to desiccation resistance by keeping the differentially raised young in conditions opposite to those during their development and again measuring water loss. We found that developmental plasticity and acclimation can completely account for the existing intraspecific variability in desiccation resistance under certain conditions. In fact, developmental and acclimatory changes can equal genetically based differences of the populations. This phenotypic plasticity can operate relatively quickly and therefore may attenuate the actions of natural selection. Understanding the extent and nature of such flexibility is critical to our understanding intraspecific variability and the consequences of changing climate.

  8. Alternate use of good quality and saline irrigation water for tomato production

    International Nuclear Information System (INIS)

    Mehaibi, A.; Rehranan, O.U.; Elamin, N.S.

    2007-01-01

    A pot experiment was set in a completely randomized design. With factorial arrangement on tomato (Lycopersicon esoulentum cv Tatto) to examine the effect of alternate irrigation with good quality and saline 4'aters and mineral fertilization on yield an mineral constituents. The experiment consisted of two irrigation practices (IRI-Continuous irrigation with water of EC 1.0 Ds m and IR2=Alternate irrigation with water of EC 10 and 5.1 d elm) two levels of phosphorous (P1 160 and P2=215 kg P/sub 2/ O/sub 5/ha) added at the beginning of the experiment. There were three nitrogen levels (N0=0, N1=370 and N2=375 kg N/ha) split into six doses a basal dose of potassium was added at the rate of 175 kg K/sub 2/ha. One healthy seedling of tomato was transplanted 3 weeks after germination in each pot (0.07 m/sup 2/) filled with soil classified as Torrifluvents. The treatments were replicated thrice and the pots were put in an open area of Agriculture Research Station Rumais Sultanate of Oman. Equal quantities of good water and good+saline (alternatively) waters were applied per treatments the alternate irrigation was started 15 days after transplanting Mature fruit was plucked; yield total soluble solids TSS) and mineral constituents were determined the results indicated that alternate irrigation (IR2) increased overall yield only by 21% in the first year but decreased it by 21% in the second indicating cumulative effect of salt accumulation Nitrogen application showed a significant linear response in tomato fruit yield. The effect of P application and interactions between treatments were non-significant in both the years. Alternate irrigation mineral fertilization increased the total soluble solids significantly Nitrogen application at the rate of 370 kg N ha (NI) gave the highest total soluble solids (TSS) in the two water treatments with phosphorus application rate of 215 kg P/sub 2/O/sub 5/ha (P2). On the other hand, when nitrogen application rate was increased to 735 kg

  9. Tap water versus sterile saline solution in the colonisation of skin wounds.

    Science.gov (United States)

    Resende, Margarida Mc; Rocha, Cleber A; Corrêa, Nely Fm; Veiga, Renato Rg; Passos, Sandro Jf; Novo, Neil F; Juliano, Yara; Damasceno, Carlos Av

    2016-08-01

    Irrigating wounds with tap water does not increase colonisation, but controlled studies are required for further evidence. Microbial colonisation was assessed in skin wounds, before and after irrigation with tap water, and was compared with irrigation using 0·9% sodium chloride sterile solution. The study included 120 subjects with chronic, traumatic, vascular, pressure or neuropathic wounds. A total of 60 wounds were randomly assigned to be irrigated with tap water (tap water group) and another 60 to be irrigated with 0·9% sodium chloride sterile solution (saline group), at a pressure of 0·46-0·54 PSI. Samples were collected from the centre of each wound using Levine's technique, before and after irrigation, and cultivated in thioglycollate, hypertonic mannitol agar, eosin methylene blue (EMB) agar, blood agar and Sabouraud agar at 37°C for 72 hours. There was concordance (kappa test) and discordance (McNemar test) regarding the count of positive and/or negative samples before and after irrigation in each group. The proportion of reduction of positive samples was similar for both groups in all cultures. Colony-forming unit count before and after irrigation was similar in both groups and in all cultures, except for the culture in hypertonic mannitol agar from the tap water group, for which the count was lower after irrigation (Wilcoxon z = 2·05, P = 0·041). It is concluded that skin wound irrigation with tap water leads to further reduction of Gram-positive bacteria compared with 0·9% sodium chloride sterile solution, with no difference in colonisation of haemolytic bacteria, Gram-negative bacteria and fungi. © 2015 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  10. Geochemistry of sediment moisture in the Badain Jaran desert: Insights into palaeo-environmental changes and water rock interaction

    Science.gov (United States)

    Jin, L.; Edmunds, W. M.; Lu, Z.; Ma, J.

    2012-12-01

    Surface water can move downward through the unsaturated zone before recharging groundwater. Geochemical profiles within the unsaturated zone enable estimation of groundwater recharge rates and retain information related to hydrologic conditions and environmental changes. Using immiscible liquid displacement techniques to extract the interstitial water from low moisture sediments allows the direct investigation of geochemistry of moisture from unsaturated materials and its continuity to the water table. A new immiscible liquid has now been successfully tested in a previous study (Jin and Edmunds, 2010). Here we present data for the first field application of the technique. Two sediment cores were collected at Baoritaolegai (BA) and Sayinwusu (SS) in the Badain Jaran desert in NW China. Both cores have moisture contents between 1-5%. The extracted interstitial waters were then analyzed to illustrate the recharge history, natural geochemical processes and possible anthropogenic influence. The calculated recharge rates at sites BA and SS from the conservative tracer Cl- were low, 1.5-3.0 mm/year. Major cations in two profiles showed relative low concentrations in the unsaturated zone and high concentrations in the capillary fringe and into the water table. Low recharge rates and cation chemistry demonstrate that the unsaturated zone moisture is derived from modern atmospheric inputs and water rock interaction but is an insignificant source of the groundwater in the area. This is consistent with the previous work at this site BA, showing that the groundwater which feeds nearby lakes is palaeowater and of different chemistry to the present day recharge. In addition, ratios of SO42- over Cl- in BA and SS profiles showed increasing trends since 1990s, which suggest higher atmospheric input of sulfur from industrial development. Direct extraction of moisture from the unsaturated zone has strong potential for monitoring environmental change.

  11. High bacterial diversity of biological soil crusts in water tracks over permafrost in the high arctic polar desert.

    Science.gov (United States)

    Steven, Blaire; Lionard, Marie; Kuske, Cheryl R; Vincent, Warwick F

    2013-01-01

    In this study we report the bacterial diversity of biological soil crusts (biocrusts) inhabiting polar desert soils at the northern land limit of the Arctic polar region (83° 05 N). Employing pyrosequencing of bacterial 16S rRNA genes this study demonstrated that these biocrusts harbor diverse bacterial communities, often as diverse as temperate latitude communities. The effect of wetting pulses on the composition of communities was also determined by collecting samples from soils outside and inside of permafrost water tracks, hill slope flow paths that drain permafrost-affected soils. The intermittent flow regime in the water tracks was correlated with altered relative abundance of phylum level taxonomic bins in the bacterial communities, but the alterations varied between individual sampling sites. Bacteria related to the Cyanobacteria and Acidobacteria demonstrated shifts in relative abundance based on their location either inside or outside of the water tracks. Among cyanobacterial sequences, the proportion of sequences belonging to the family Oscillatoriales consistently increased in relative abundance in the samples from inside the water tracks compared to those outside. Acidobacteria showed responses to wetting pulses in the water tracks, increasing in abundance at one site and decreasing at the other two sites. Subdivision 4 acidobacterial sequences tended to follow the trends in the total Acidobacteria relative abundance, suggesting these organisms were largely responsible for the changes observed in the Acidobacteria. Taken together, these data suggest that the bacterial communities of these high latitude polar biocrusts are diverse but do not show a consensus response to intermittent flow in water tracks over high Arctic permafrost.

  12. High bacterial diversity of biological soil crusts in water tracks over permafrost in the high arctic polar desert.

    Directory of Open Access Journals (Sweden)

    Blaire Steven

    Full Text Available In this study we report the bacterial diversity of biological soil crusts (biocrusts inhabiting polar desert soils at the northern land limit of the Arctic polar region (83° 05 N. Employing pyrosequencing of bacterial 16S rRNA genes this study demonstrated that these biocrusts harbor diverse bacterial communities, often as diverse as temperate latitude communities. The effect of wetting pulses on the composition of communities was also determined by collecting samples from soils outside and inside of permafrost water tracks, hill slope flow paths that drain permafrost-affected soils. The intermittent flow regime in the water tracks was correlated with altered relative abundance of phylum level taxonomic bins in the bacterial communities, but the alterations varied between individual sampling sites. Bacteria related to the Cyanobacteria and Acidobacteria demonstrated shifts in relative abundance based on their location either inside or outside of the water tracks. Among cyanobacterial sequences, the proportion of sequences belonging to the family Oscillatoriales consistently increased in relative abundance in the samples from inside the water tracks compared to those outside. Acidobacteria showed responses to wetting pulses in the water tracks, increasing in abundance at one site and decreasing at the other two sites. Subdivision 4 acidobacterial sequences tended to follow the trends in the total Acidobacteria relative abundance, suggesting these organisms were largely responsible for the changes observed in the Acidobacteria. Taken together, these data suggest that the bacterial communities of these high latitude polar biocrusts are diverse but do not show a consensus response to intermittent flow in water tracks over high Arctic permafrost.

  13. Determination of Suitable Water Salinity and Live Food in The Rearing of Eel (Anguilla bicolor Fry

    Directory of Open Access Journals (Sweden)

    . Sutrisno

    2008-01-01

    Full Text Available This study was conducted to determine suitable water salinity and live food in the rearing of eel,  Anguilla bicolor fry.  Eel fry in weight of 0.15±0.008 g/tail were reared at controlled tank at density of 2 fish liter-1 for 42 days.  Experiment was devided into two steps.  In the first step of experiment, eel fry were reared at different water salinity, i.e., 0; 5; 10 and 15 ppt.  Fish were fed on Tubifex at satiation.  The best result from the first experiment was then used in the second step of study to examine proper live food for eel fry.  Fish were fed on live food (Tubifex, Artemia, or Spirulina at 10% body weight.  Survival rate, specific growth rate and food conversion ratio were observed.  The result of experiment showed that survival rate of eel fry reared in water salinity of 5 ppt (100%, 10 (96% and 15 ppt (97% was higher (p0.05.  The best food conversion ratio was also being obtained at treatment of 5 ppt (3.36, followed repectively by 10 ppt (5.11, 15 ppt (5.70 and 0 ppt (21.11.  No different survival rate of eel fry by feeding on different live food was obtained.  Higher specific growth rate was achieved at feeding of Artemia (2.82% per day, followed respectively by Tubifex (1.85% per day and Spirulina (0.15% per day.  Food coversion ratio in each treatment was 4.42, 2.77 and 134.33, respectively. Keywords:  eel, salinity, live food   ABSTRAK Penelitian dilakukan dengan tujuan untuk mengetahui salinitas air dan jenis pakan alami yang tepat dalam pemeliharaan benih ikan sidat (Anguilla bicolor. Benih sidat dengan berat rata-rata 0,15±0,008 g/ekor dipelihara selama 42 hari pada wadah terkontrol dengan kepadatan 2 ekor/liter. Penelitian dibagi kedalam dua tahap. Pada tahap pertama benih sidat diperlihara pada media dengan salinitas 0; 5, 10 dan 15 ppt.  Pakan alami berupa cacing sutera diberikan secara satiasi.  Salinitas terbaik hasil penelitian tahap pertama digunakan pada penelitian tahap kedua untuk

  14. Rock Physics of Reservoir Rocks with Varying Pore Water Saturation and Pore Water Salinity

    OpenAIRE

    Katika, Konstantina; Fabricius, Ida Lykke

    2016-01-01

    Advanced waterflooding (injection of water with selective ions in reservoirs) is amethod of enhanced oil recovery (EOR) that has attracted the interest of oil and gas companies that exploit the Danish oil and gas reservoirs. This method has been applied successfully in oil reservoirs and in the Smart Water project performed in a laboratory scale in order to evaluate the EOR processes in selected core plugs. A major step towards this evaluation is to identify the composition of the injected wa...

  15. Increasing Gas Hydrate Formation Temperature for Desalination of High Salinity Produced Water with Secondary Guests

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Jong-Ho; Seol, Yongkoo

    2013-10-07

    We suggest a new gas hydrate-based desalination process using water-immiscible hydrate formers; cyclopentane (CP) and cyclohexane (CH) as secondary hydrate guests to alleviate temperature requirements for hydrate formation. The hydrate formation reactions were carried out in an isobaric condition of 3.1 MPa to find the upper temperature limit of CO2 hydrate formation. Simulated produced water (8.95 wt % salinity) mixed with the hydrate formers shows an increased upper temperature limit from -2 °C for simple CO2 hydrate to 16 and 7 °C for double (CO2 + CP) and (CO2 + CH) hydrates, respectively. The resulting conversion rate to double hydrate turned out to be similar to that with simple CO2 hydrate at the upper temperature limit. Hydrate formation rates (Rf) for the double hydrates with CP and CH are shown to be 22 and 16 times higher, respectively, than that of the simple CO2 hydrate at the upper temperature limit. Such mild hydrate formation temperature and fast formation kinetics indicate increased energy efficiency of the double hydrate system for the desalination process. Dissociated water from the hydrates shows greater than 90% salt removal efficiency for the hydrates with the secondary guests, which is also improved from about 70% salt removal efficiency for the simple hydrates.

  16. Formation of ‘Crioula’ guava rootstock under saline water irrigation and nitrogen doses

    Directory of Open Access Journals (Sweden)

    Leandro de P. Souza

    Full Text Available ABSTRACT The objective of this research was to evaluate the growth and formation of fresh and dry weight of ‘Crioula’ guava rootstock irrigated with waters of different saline levels and nitrogen (N doses, in an experiment conducted in plastic tubes under greenhouse conditions. The experimental design was randomized blocks, in a 5 x 4 factorial scheme with four replicates, and the treatments consisted of five levels of water electrical conductivity - ECw (0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1 and four N doses (70, 100, 130 and 160% of the N dose recommended for the cultivation of guava seedlings, cv. ‘Paluma’. The dose referring to 100% corresponds to 773 mg of N dm-3. The highest growth of ‘Crioula’ guava rootstock was obtained with ECw of 0.3 dS m-1 and fertilization of 541.1 mg N dm-3 of soil; increasing N doses did not reduce the deleterious effect of the salt stress on the growth and phytomass formation of ‘Crioula’ guava rootstock; irrigation with water of up to 1.75 dS m-1, in the production of guava rootstocks, promotes acceptable reduction of 10% in growth and quality of the seedlings.

  17. Urbanization accelerates long-term salinization and alkalinization of fresh water

    Science.gov (United States)

    Kaushal, S.; Duan, S.; Doody, T.; Haq, S.; Smith, R. M.; Newcomer Johnson, T. A.; Delaney Newcomb, K.; Gorman, J. K.; Bowman, N.; Mayer, P. M.; Wood, K. L.; Belt, K.; Stack, W.

    2017-12-01

    Human dominated land-use increases transport a major ions in streams due to anthropogenic salts and accelerated weathering. We show long-term trends in calcium, magnesium, sodium, alkalinity, and hardness over 50 years in the Baltimore metropolitan region and elsewhere. We also examine how major ion concentrations have increased significantly with impervious surface cover in watersheds across land use. Base cations show strong relationships with acid anions, which illustrates the coupling of major biogeochemical cycles in urban watersheds over time. Longitudinal patterns in major ions can also show increasing trends from headwaters to coastal waters, which suggests coupled biogeochemical cycles over space. We present new results from manipulative experiments and long-term monitoring across different urban regions regarding patterns and processes of salinization and alkalinization. Overall, our work demonstrates that urbanization dramatically increases major ions, ionic strength, and pH over decades from headwaters to coastal waters, which impacts the integrity of aquatic life, infrastructure, drinking water, and coastal ocean alkalinization.

  18. Effects of changes in water salinity upon exercise and cardiac performance in the European seabass ( Dicentrarchus labrax )

    DEFF Research Database (Denmark)

    Chatelier, A.; McKenzie, David; Claireaux, G.

    2005-01-01

    The European seabass is an active euryhaline teleost that migrates and forages in waters of widely differing salinities. Oxygen uptake (M-O2) was measured in seabass (average mass and forklength 510 g and 34 cm, respectively) during exercise at incremental swimming speeds in a tunnel respirometer...... in seawater (SW) at a salinity of 30 parts per thousand and temperature of 14 degrees C, and their maximal sustainable (critical) swimming speed (U-crit) determined. Cardiac output (Q) was measured via an ultrasound flow probe on their ventral aorta. The fish were then exposed to acute reductions in water...... salinity, to either SW (control), 10 parts per thousand, 5 parts per thousand, or freshwater (FW, 0 parts per thousand), and their exercise and cardiac performance measured again, 18 h later. Seabass were also acclimated to FW for 3 weeks, and then their exercise performance measured before and at 18 h...

  19. Distribution of Glass Eel by the Water Surface Salinity Using Landsat TM at Pelabuhan Ratu Bay, West Java

    Science.gov (United States)

    Irianto, D. S.; Supriatna; Pin, TjiongGiok

    2016-11-01

    Eel (Anguilla spp.) is consumed fish that has an important economic value, either for local or international market. Pelabuhanratu Bay is an area with big potential for supplying eel seed. One of important factor, which affect an eel existence, is salinity, because eel migrate from fresh water, brackish, and sea naturally although the otherwise so that need ways to describe the distribution of glass eel by the salinity. To find out the percentage of salinity, it obtained from Landsat 8 Imagery in year 2015 using salinity prediction of Algorithm Cimandiri. The research has been conducted at Cimandiri Estuary, Citepus Estuary, and Cimaja Estuary based on wet and dry months. The existence of glass eel which is obtained from the catch was occurs on dry month when the most catch was occurs at the edge of estuary. The catch is reduced if it's farther from the edge of estuary, at the beach towards the sea and the inside of the river mouth with the percentage of salinity towards the sea is increase while the percentage of salinity towards the river is decrease.

  20. Meal consumption is ineffective at maintaining or correcting water balance in a desert lizard, Heloderma suspectum.

    Science.gov (United States)

    Wright, Christian D; Jackson, Marin L; DeNardo, Dale F

    2013-04-15

    Many xeric organisms maintain water balance by relying on dietary and metabolic water rather than free water, even when free water may be available. For such organisms, hydric state may influence foraging decisions, since meal consumption is meeting both energy and water demands. To understand foraging decisions it is vital to understand the role of dietary water in maintaining water balance. We investigated whether meal consumption was sufficient to maintain water balance in captive Gila monsters (Heloderma suspectum) at varying levels of dehydration. Gila monsters could not maintain water balance over long time scales through meal consumption alone. Animals fed a single meal took no longer to dehydrate than controls when both groups were deprived of free water. Additionally, meal consumption imparts an acute short-term hydric cost regardless of hydration state. Meal consumption typically resulted in a significant elevation in osmolality at 6 h post-feeding, and plasma osmolality never fell below pre-feeding levels despite high water content (~70%) of meals. These results failed to support our hypothesis that dietary water is valuable to Gila monsters during seasonal drought. When considered in conjunction with previous research, these results demonstrate that Gila monsters, unlike many xeric species, are heavily reliant on seasonal rainfall and the resulting free-standing water to maintain water balance.

  1. Modeling the effects of saline groundwater and irrigation water on root zone salinity and sodicity dynamics in agro-ecosystems

    OpenAIRE

    Shah, S.H.H.

    2013-01-01

    Recent trends and future projections suggest that the need to produce more food and fibre for the world’ s expanding population will lead to an increase in the use of marginal-quality water and land resources (Bouwer, 2000; Gupta and Abrol, 2000; Wild, 2003). This is particularly relevant to less-developed, arid and semi-arid countries, in which problems of soil and water quality degradation are common (Qadir and Oster, 2004). The aim, therefore, should be to increase yield per unit of land ...

  2. Chemical constituents of Cenchrus ciliaris L. from the Cholistan desert, Pakistan

    OpenAIRE

    Ashraf Muhammad Aqeel; Mahmood Karamat; Yusoff Ismail; Qureshi Ahmad Kaleem

    2013-01-01

    The Cholistan Desert is an extension of the Great Indian Desert, covering an area of 26,330 km2. The desert can be divided into two main geomorphic regions: the northern region, known as Lesser Cholistan, constituting the desert margin and consisting of a series of saline alluvial flats alternating with low sand ridges/dunes; and the southern region, known as Greater Cholistan, a wind-resorted sandy desert comprised of a number of old Hakra River terraces w...

  3. Modeling the effects of saline groundwater and irrigation water on root zone salinity and sodicity dynamics in agro-ecosystems

    NARCIS (Netherlands)

    Shah, S.H.H.

    2013-01-01

    Recent trends and future projections suggest that the need to produce more food and fibre for the world’ s expanding population will lead to an increase in the use of marginal-quality water and land resources (Bouwer, 2000; Gupta and Abrol, 2000; Wild, 2003). This is particularly

  4. Modeling the effects of saline groundwater and irrigation water on root zone salinity and sodicity dynamics in agro-ecosystems

    NARCIS (Netherlands)

    Shah, S.H.H.

    2013-01-01

    Recent trends and future projections suggest that the need to produce more food and fibre for the world’ s expanding population will lead to an increase in the use of marginal-quality water and land resources (Bouwer, 2000; Gupta and Abrol, 2000; Wild, 2003). This is particularly relevant to

  5. Chemical Composition, in vitro Digestibility and Fermentative Gas Production of Kochia scoparia Irrigated by Water Containing Different Level of Salinity

    Directory of Open Access Journals (Sweden)

    reza valizadeh

    2016-11-01

    Full Text Available Introduction Shortage of feedstuff is one of the important problems of animal nutrition in Iran. Salinity is a global problem worldwide in particular in arid and semi-arid zones such as Iran. Salinity is an important factor in the growth of plants. Its initial effect to plants is through its effect in the availability of water to plants. Halophytes have good ability to draw water from soils of low water potential due to their ability to maintain a salt balance comparable to the salt in the soil they are growing. Lands in high irrigation districts are susceptible to soil salinization. Soil salinization is the primary cause of productivity decline in highly developed and irrigated land schemes While the increase in soil and water salinity in many agricultural areas of the world has created major challenges in the production of food crops, it has also presented some new prospects for livestock agriculture. There are plants that grow under saline conditions, and historically, they have been opportunistically used as fodder for grazing livestock or as components of mixed rations to replace roughage. Using of seawater for irrigation of this plant because of shortage of sweet water and for higher production of these plants was necessary for feedstuff. The aim of this study was evaluation of Chemical composition, In vitro digestibility and gas production of Kochia scoparia under six level of salinity including 10, 20, 30, 40, 50, 60 ds/m. Materials and Methods The Kochia scoparia was irrigated by normal tap water (the control and water containing 6 levels of salinity including 10, 20, 30, 40, 50, 60 deci Siemens per meter (ds/m. The salinity was applied gradually in accordance with the plant growth advancement (2 ds/m increment per each irrigation period. Oven dried (65◦C for 48 h chopped samples were ground to pass through a 1-mm screen. The samples were analyzed according to the standard procedures for chemical composition (AOAC 2000, Van-Soest et

  6. Regional water table (2016) in the Mojave River and Morongo groundwater basins, southwestern Mojave Desert, California

    Science.gov (United States)

    Dick, Meghan; Kjos, Adam

    2017-12-07

    From January to April 2016, the U.S. Geological Survey (USGS), the Mojave Water Agency, and other local water districts made approximately 1,200 water-level measurements in about 645 wells located within 15 separate groundwater basins, collectively referred to as the Mojave River and Morongo groundwater basins. These data document recent conditions and, when compared with older data, changes in groundwater levels. A water-level contour map was drawn using data measured in 2016 that shows the elevation of the water table and general direction of groundwater movement for most of the groundwater basins. Historical water-level data stored in the USGS National Water Information System (https://waterdata.usgs.gov/nwis/) database were used in conjunction with data collected for this study to construct 37 hydrographs to show long-term (1930–2016) and short-term (1990–2016) water-level changes in the study area.

  7. Biotechnological Applications Derived from Microorganisms of the Atacama Desert

    Directory of Open Access Journals (Sweden)

    Armando Azua-Bustos

    2014-01-01

    Full Text Available The Atacama Desert in Chile is well known for being the driest and oldest desert on Earth. For these same reasons, it is also considered a good analog model of the planet Mars. Only a few decades ago, it was thought that this was a sterile place, but in the past years fascinating adaptations have been reported in the members of the three domains of life: low water availability, high UV radiation, high salinity, and other environmental stresses. However, the biotechnological applications derived from the basic understanding and characterization of these species, with the notable exception of copper bioleaching, are still in its infancy, thus offering an immense potential for future development.

  8. Tritiated-water heat-tolerance index to predict the growth rate in calves in hot deserts

    International Nuclear Information System (INIS)

    Kamal, T.H.

    1982-01-01

    It was the intention of this study to develop a heat-tolerance index that predicts at an early age the growth rate of calves in a hot desert area (Inshas). Twelve female Friesian calves aged 13-15 months were maintained in climatic chambers for 2 weeks at a mild climate (control), followed by 2 weeks at a hot climate (experimental). Determinations of body water content, body solids, body weight and final rectal temperature were undertaken during the second week of the control and experimental periods. Afterwards the animals were transferred to the farm and maintained outdoors; they were weighed at the end of the 4 summer months. Body water content and rectal temperature were 9.47 and 2.42%, respectively, higher in the hot climate than in the control at P 1 ) or body solids content (X 2 ) that had occurred previously during the 2-weeks heat stress in the climatic chamber by using the equation Y = 39.44 - 1.65X 1 or Y = 45.02 - 1.27X 2 . The standard errors of the regression coefficients for the two equations were 0.094 and 0.132, respectively. The standard errors of the predicted Y for the two equations were 0.207 and 0.218, respectively

  9. Assessing Water Stress of Desert Tamarugo Trees Using in situ Data and Very High Spatial Resolution Remote Sensing

    Directory of Open Access Journals (Sweden)

    Edmundo Acevedo

    2013-10-01

    Full Text Available The hyper-arid Atacama Desert is one of the most extreme environments for life and only few species have evolved to survive its aridness. One such species is the tree Prosopis tamarugo Phil. Because Tamarugo completely depends on groundwater, it is being threatened by the high water demand from the Chilean mining industry and the human consumption. In this paper, we identified the most important biophysical variables to assess the water status of Tamarugo trees and tested the potential of WorldView2 satellite images to retrieve these variables. We propose green canopy fraction (GCF and green drip line leaf area index (DLLAIgreen as best variables and a value of 0.25 GCF as a critical threshold for Tamarugo survival. Using the WorldView2 spectral bands and an object-based image analysis, we showed that the NDVI and the Red-edge Chlorophyll Index (CIRed-edge have good potential to retrieve GCF and DLLAIgreen. The NDVI performed best for DLLAIgreen (RMSE = 0.4 while the CIRed-edge was best for GCF (RMSE = 0.1. However, both indices were affected by Tamarugo leaf movements (leaves avoid facing direct solar radiation at the hottest time of the day. Thus, monitoring systems based on these indices should consider the time of the day and the season of the year at which the satellite images are acquired.

  10. Salinity, water hardness, and dissolved organic carbon modulate degradation of peracetic acid (PAA) compounds in aqueous solutions

    Science.gov (United States)

    Peracetic acid (PAA) is used in aquaculture under different conditions for disinfection purposes. However, there is a lack of information about its environmental fate, particularly its persistence in aquatic systems with different chemistries. Therefore, the impact of water hardness, salinity, and d...

  11. Effect of saline water on growth, yield and N2 fixation by faba bean and lentil plants using nitrogen-15

    International Nuclear Information System (INIS)

    Gadalla, A.M.; Galal, Y.G.M.; Elakel, E.A.; Ismail, H.; Hamdy, A.

    2003-01-01

    This work had been carried out under greenhouse conditions through joint research project between international agronomic mediterranean (IAM, Bari), italy and soils and water dept., Egyptian atomic energy authority. The aim of this dy was to assess the effect of saline water irrigation on growth, yield and nitrogen fixation (% Ndfa) by faba bean and lentil plants inoculated with selected rhizobium strains. Four saline irrigation water levels (fresh water, 3.6 and ds/m) were used. 20 kg N/ha as ammonium sulfate contained 10% N-15 atom excess was applied for quantification of biological N-fixation N-portions derived from fertilizer (Ndff). Results showed that high levels of salinity negatively affected seed yield and N accumulated in tissue of faba bean. Similar trend was noticed with dry matter of lentil while shoot-N was increased at 6 and 9 ds/m. Both leguminous crops were mainly dependent on N 2 fixation as an important source of nitrogen nutrition. Under adverse conditions salinity, the plants gained some of their N requirements from the other two N sources (Ndff and Ndfs). Application of the suitable Rhizobium bacteria strains could be beneficial for both the plant growth and soil fertility via N 2 fixation

  12. Accumulation of Chiro-inositol and Other Non-structural Carbohydrates in Limonium Species in Response to Saline Irrigation Waters

    Science.gov (United States)

    Two statice cultivars, Limonium perezii (Stapf) F. T. Hubb cv. ‘Blue Seas’ and L. sinuatum (L.) Mill ‘American Beauty’, were grown in greenhouse sand tanks to determine the effect of salt stress on carbohydrate accumulation and partitioning. Irrigation waters were prepared to simulate typical saline...

  13. Influence of drinking water salinity on carcass characteristics and meat quality of Santa Inês lambs.

    Science.gov (United States)

    Castro, Daniela P V; Yamamoto, Sandra M; Araújo, Gherman G L; Pinheiro, Rafael S B; Queiroz, Mario A A; Albuquerque, Ítalo R R; Moura, José H A

    2017-08-01

    This study aimed to evaluate the effects of different salinity levels in drinking water on the quantitative and qualitative characteristics of lamb carcass and meat. Ram lambs (n = 32) were distributed in a completely randomized design with four levels of salinity in the drinking water (640 mg of total dissolved solids (TDS)/L of water, 3188 mg TDS/L water, 5740 mg TDS/L water, and 8326 mg TDS/L water). After slaughter, blending, gutting, and skinning the carcass, hot and biological carcass yields were obtained. Then, the carcasses were cooled at 5 °C for 24 h, and then, the morphometric measurements and the cold carcass yield were determined and the commercial cuts made. In the Longissimus lumborum muscle color, water holding capacity, cooking loss, shear force, and chemical composition were determined. The yields of hot and cold carcass (46.10 and 44.90%), as well as losses to cooling (2.40%) were not affected (P > 0.05) by the salinity levels in the water ingested by the lambs. The meat shear force was 3.47 kg/cm 2 and moisture, crude protein, ether extract, and ash were 73.62, 22.77, 2.5, and 4.3%, respectively. It is possible to supply water with salinity levels of up to 8326 mg TDS/L, because it did not affect the carcass and meat characteristics of Santa Inês lambs.

  14. Spatial-temporal variability of soil water content in a cropland-shelterbelt-desert site in an arid inland river basin of Northwest China

    Science.gov (United States)

    Shen, Qin; Gao, Guangyao; Hu, Wei; Fu, Bojie

    2016-09-01

    Knowledge of the spatial-temporal variability of soil water content (SWC) is critical for understanding a range of hydrological processes. In this study, the spatial variance and temporal stability of SWC were investigated in a cropland-shelterbelt-desert site at the oasis-desert ecotone in the middle of the Heihe River Basin, China. The SWC was measured on 65 occasions to a depth of 2.8 m at 45 locations during two growing seasons from 2012 to 2013. The standard deviation of the SWC versus the mean SWC exhibited a convex upward relationship in the shelterbelt with the greatest spatial variation at the SWC of around 22.0%, whereas a linearly increasing relationship was observed for the cropland, desert, and land use pattern. The standard deviation of the relative difference was positively linearly correlated with the SWC (p statistics of temporal stability of the SWC could be presented equally well with a low frequency of observation (30-day interval) as with a high frequency (5-day interval). Sampling frequency had little effect on the selection of the representative locations of the field mean SWC. This study provides useful information for designing the optimal strategy for sampling SWC at the oasis-desert ecotone in the arid inland river basin.

  15. Thar Desert

    Science.gov (United States)

    2001-01-01

    This ASTER sub-scene covers an area of 12 x 15 km in NW India in the Thar Desert. The sand dunes of the Thar Desert constantly shift and take on new shapes. Located in northwestern India and eastern Pakistan, the desert is bounded on the south by a salt marsh known as the Rann of Kutch, and on the west by the Indus River plain. About 800 kilometers long and about 490 kilometers wide, the desert's terrain is mainly rolling sandhills with scattered growths of shrub and rock outcroppings. Only about 12 to 25 centimeters of rain fall on the desert each year, and temperatures rise as high as 52 degrees Celsius. Much of the population is pastoral, raising sheep for their wool. The image is located at 24.4 degrees north latitude and 69.3 degrees east longitude. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  16. [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.

  17. Pepper plants growth, yield, photosynthetic pigments, and total phenols as affected by foliar application of potassium under different salinity irrigation water

    Science.gov (United States)

    Irrigation with high salinity water influences plant growth, production of photosynthetic pigments and total phenols, leading to reduction in crop yield and quality. Foliar application of macro- and/or micro-nutrients can, to some extent, mitigate negative effects of high salinity irrigation water o...

  18. Investigation of Chemical and Radiochemical Fingerprints of Water Resources in Siwa Oasis, Western Desert, Egypt

    International Nuclear Information System (INIS)

    El-Sayed, S.A.; Allam, Kh.A.; Salama, M.H.; El Begawy, H.

    2017-01-01

    Water resources in Siwa oasis, Egypt; included the Nubian sandstone aquifer system (NSSAS), Tertiary carbonate aquifer system (TCAS) as well as springs and lakes. Existing chemical and radiochemical fingerprints of these resources in the central and western parts of the oasis were examined based on the analyses of 30 water samples collected in 2015. In each sample, the analyzed chemical and radioisotopic constituents were Cl - , SO 4 2- , CO 3 2- , HCO 3 - , Na + , K + , Ca 2+ and Mg 2+ , Al, B, Ba, Cd, Co, Fe, Cu, Mn, Mo, Ni, Pb, Sr, V, Zn, Si and Cr, 226 Ra, 232 Th and 40 K. Other physical properties included ph and TDS were measured in the field. The chemical analysis was carried out following the ASTM methods, while the radiochemical measurements were done using a hyper pure germanium (HPGe) gamma ray spectrometry. Results of this work may be advantage ous to promote the hydrologic database in the oasis, where levels of the natural radioactivity in groundwater resources were established for the first time. Water resources were classified based on their contents of TDS into fresh water for the NSSAS, brackish to salty water for TCAS, brackish water for springs and brine water for lakes. The artesian water of the NSSAS and TCAS and water of the springs were alkaline, while the water of the lakes was acidic. Chemical characters of the ground water of the NSSAS reflected a little response to the processes of water-rock interactions, and the vice versa was observed for the groundwater of the TCAS. The ground water of the NSSAS was dominated by HCO 3- Na genetic type characterizing the meteoric origin of water. The ground water of the TCAS was characterized by the presence of three genetic types of water (SO 4- Na, Cl-Mg, and Cl-CA water), indicating the modification of the recharged water from the underlain NSSAS due to the effects of water sediment interactions and mixing with trapped ancient sea water. The chemical properties of spring water were, greatly similar

  19. Yield and Nitrogen Assimilation of Potato Varieties (Solanum tuberosum L.) as Affected by Saline Water Irrigation and Organic Manure

    International Nuclear Information System (INIS)

    Hamdy, A.; Gadalla, A.M.; El-Kholi, A.F.; Galal, Y.G.M.; Ismail, M.M.

    2008-01-01

    The experiment was carried out in lysimeter under controlled greenhouse conditions. Saline water was applied in different levels, i.e. fresh water, 3 and 6 dS/m. Organic manure were applied to soil at rates of 0, 2.6 and 5.2 kg/m2. Basal recommended doses of P and K were applied. Labelled urea (10% a.e.) was applied at rate of 200 kg N/ha. 15 N technique was used to evaluate N-uptake and fertilizer efficiency. Comparison held between the two potato varieties indicated that higher reduction in shoot dry weight was recorded with Nicola variety than Spunta one which irrigated with 6 dS/m water salinity level. Addition of 2.6 kg/m 2 organic rate induced an increase in N uptake with fresh water and 3 dS/m salinity then tended to decrease with 6 dS/m level as compared to the untreated control. Concerning the nitrogen fertilization, data of 15 N analysis showed that, water salinity levels combined with organic addition rates were frequently affected the nitrogen derived from fertilizer and consequently the fertilizer use efficiency. Most of nitrogen was derived from the applied nitrogen fertilizer with maximum accumulation in tuber rather than shoots or roots of both potato varieties. Gradual increase of tuber starch with increasing salinity levels was noticed with addition of 2.6 kg/m 2 of organic matter. In general, Spunta variety showed some superiority in tuber starch over those of Nicola variety tuber

  20. Morphology and Kinetics of Growth of CaCO3 Precipitates Formed in Saline Water at 30°C

    Science.gov (United States)

    Sui, Xin; Wang, Baohui; Wu, Haiming

    2018-02-01

    The crystallization kinetics and morphology of CaCO3 crystals precipitated from the high salinity oilfield water were studied. The crystallization kinetics measurements show that nucleation and nuclei growth obey the first order reaction kinetics. The induction period of precipitation is extended in the high salinity solutions. Morphological studies show that impurity ions remain mostly in the solution phase instead of filling the CaCO3 crystal lattice. The morphology of CaCO3 precipitates can be changed from a smooth surface (calcite) to rough spheres (vaterite), and spindle rod bundles, or spherical, ellipsoid, flowers, plates and other shapes (aragonite).

  1. A hydrogeochemical study of rain water to characterize the source of atmospheric pollutants at Jodhpur - desert city of India (abstract)

    International Nuclear Information System (INIS)

    Shrivastava, K.L.; Ojha, S.K.

    1999-01-01

    A study was undertaken has been conducted to determined the physical parameters and chemical species in the first precipitants of the season at desert city of Jodhpur to understand firstly, the degree of pollutants in the atmosphere and secondly to identity the minerals/pollutants of the atmosphere to characterize its possible source of origin. The precipitate samples for cations and other physical and chemical parameters by standard analytical methods. The results obtained on turbidity, conductivity, total dissolved solids and the ratio of total dissolved solids and conductivity, show a moderate degree of pollutants at all the four sites, A, B, C and D but slightly higher at C and D sites. The concentration of various water-soluble chemical species present in the precipitates, specially a balance between acidic and basic constituents decides its pH value. Hydrogen ions are mainly responsible for acidification of rain waters and are derived chiefly from oxidation of SO/sub 2/ and NO/sub 2/ to from H/sub 2/SO/sub 4/ and HNO/sub 3/ respectively. Hence a correlation study carried out between H/sup */and SO/sub 4//sup --/, NO/sub 3/ and Cl. Result shows no strong correlation between H/sup +/ and Cl/up -/. A group of strongly corrected elements Cl, Na/sup +/,K/sup +/ and Mg/sup ++/ were observed representing a similar source of their origin. The atmospheric desert dust components chiefly consist of quartz, mica flakes, clays like illite, kaolinite etc., and especially clays, may neutralize the acidity of precipitates via H/sup +/ exchange. Some minerals like Halite, Gypsum, Dolomite, Calcite may get slightly dissolved in the rainwater to replace H/sup +/ ions and so, impart alkalinity. Thus, it is logical to believe that the cations may have been derived originally from some of the geological source. Some rations like Cl/Na, Mg/Na, Ca/Na are known to have been used in characterization of the source. As expected in the atmosphere of desert city, like Jodhpur, the solid

  2. Growth and yield of cowpea/sunflower crop rotation under different irrigation management strategies with saline water

    Directory of Open Access Journals (Sweden)

    Antônia Leila Rocha Neves

    2015-05-01

    Full Text Available This study aimed to evaluate the effect of management strategies of irrigation with saline water on growth and yield of cowpea and sunflower in a crop rotation. The experiment was conducted in randomized blocks with thirteen treatments and five replications. The treatments consisted of: T1 (control, T2, T3 and T4 using water of 0.5 (A1, 2.2 (A2, 3.6 (A3 and 5.0 (A4 dS m-1, respectively, during the entire crop cycle; T5, T6 and T7, use of A2, A3 and A4 water, respectively, only in the flowering and fructification stage of the crop cycle; using different water in a cyclic way, six irrigations with A1 followed by six irrigations with A2 (T8, A3 (T9 and A4, (T10, respectively; T11, T12 and T13, using water A2, A3 and A4, respectively, starting at 11 days after planting (DAP and continuing until the end of the crop cycle. These treatments were employed in the first crop (cowpea, during the dry season, and the same plots were used for the cultivation of sunflower as succeeding crop during rainy season. The strategies of use of saline water in the salt tolerant growth stage (treatments T5, T6 and T7 or cyclically (treatments T8, T9 and T10 reduced the amount of good quality water used in the production of cowpea by 34 and 47%, respectively, without negative impacts on crop yield, and did not show the residual effects of salinity on sunflower as a succeeding crop. Thus, these strategies appear promising to be employed in areas with water salinity problems in the semiarid region of Brazil.

  3. New insight into photo-bromination processes in saline surface waters: The case of salicylic acid

    Energy Technology Data Exchange (ETDEWEB)

    Tamtam, Fatima; Chiron, Serge, E-mail: serge.chiron@msem.univ-montp2.fr

    2012-10-01

    It was shown, through a combination of field and laboratory observations, that salicylic acid can undergo photo-bromination reactions in sunlit saline surface waters. Laboratory-scale experiments revealed that the photochemical yields of 5-bromosalicylic acid and 3,5-dibromosalicylic acid from salicylic acid were always low (in the 4% range at most). However, this might be of concern since these compounds are potential inhibitors of the 20{alpha}-hydroxysteroid dehydrogenase enzyme, with potential implications in endocrine disruption processes. At least two mechanisms were involved simultaneously to account for the photo-generation of brominated substances. The first one might involve the formation of reactive brominated radical species (Br{center_dot}, Br{sub 2}{center_dot}{sup -}) through hydroxyl radical mediated oxidation of bromide ions. These ions reacted more selectively than hydroxyl radicals with electron-rich organic pollutants such as salicylic acid. The second one might involve the formation of hypobromous acid, through a two electron oxidation of bromine ions by peroxynitrite. This reaction was catalyzed by nitrite, since these ions play a crucial role in the formation of nitric oxide upon photolysis. This nitric oxide further reacts with superoxide radical anions to yield peroxynitrite and by ammonium through the formation of N-bromoamines, probably due to the ability of N-bromoamines to promote the aromatic bromination of phenolic compounds. Field measurements revealed the presence of salicylic acid together with 5-bromosalicylic and 3,5-dibromosalicylic acid in a brackish coastal lagoon, thus confirming the environmental significance of the proposed photochemically induced bromination pathways. -- Highlights: Black-Right-Pointing-Pointer Brominated derivatives of salicylic acid were detected in a brackish lagoon. Black-Right-Pointing-Pointer A photochemical pathway was hypothesized to account for bromination of salicylic acid. Black

  4. Synoptic monthly gridded Global Temperature and Salinity Profile Programme (GTSPP) water temperature and salinity from January 1990 to December 2009 (NCEI Accession 0138647)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The synoptic gridded Global Temperature and Salinity Profile Programme (SG-GTSPP) provides world ocean 3D gridded temperature and salinity data in monthly increment...

  5. The role of hyperthermia in the water economy of desert birds

    NARCIS (Netherlands)

    Tieleman, B.I.; Williams, J.B.

    1999-01-01

    A number of authors have suggested that hyperthermia, the elevation of body temperature (T-b) 2 degrees-4 degrees C above normal, contributes to a reduction in total evaporative water loss (TEWL) in birds. Information about the role of hyperthermia in the water economy of birds is scattered

  6. The adjustment of avian metabolic rates and water fluxes to desert environments

    NARCIS (Netherlands)

    Tieleman, BI; Williams, JB

    2000-01-01

    We tested the hypothesis that birds in arid environments, where primary productivity is low and surface water is scarce, have reduced energy expenditure and water loss compared with their mesic counterparts. Using both conventional least squares regression and regression based on phylogenetically

  7. Restoring abandoned agricultural lands in cold desert shrublands: Tradeoffs between water availability and invasive species

    Science.gov (United States)

    Jeanne C. Chambers; Eric P. Eldredge; Keirith A. Snyder; David I. Board; Tara Forbis de Queiroz; Vada Hubbard

    2014-01-01

    Restoration of abandoned agricultural lands to create resilient ecosystems in arid and semi-arid ecosystems typically requires seeding or transplanting native species, improving plant-soil-water relations, and controlling invasive species. We asked if improving water relations via irrigation or surface mulch would result in negative tradeoffs between native species...

  8. Functional groups in North Chilean desert shrub species, based on the water sources used

    International Nuclear Information System (INIS)

    Squeo, Francisco A; Olivares, Nancy; Olivares, Sandra; Jorquera, Carmen; Pollastri, Alberto; Aguirre, Evelyn; Aravena, Ramon; Ehleringer, James R

    1999-01-01

    Primary productivity and vegetation structure in arid ecosystems are determined by water availability. In studies conducted in the coastal dry land of North Central Chile (29 degrees 43'S; 71degrees 14'0, 300m), the mechanisms to use different water sources by shrubs species, in two contrasting rainfall years were compared. Information on pheno logical studies, root architecture and water sources used by shrubs through the use of stable isotopes is are discussed. Six functional groups based on water uptake and water use are recognized. The functional groups were defined based on their habits (deciduous and evergreen), their root systems, (shallow, dimorphic and deep), and their ability to use different water sources (surficial and/or deep). Because of the differential impact of the goat overgrazing on different functional groups, this would result on a lower utilization of surficial waters. A management and/or restoration plan should maximize the use of all water sources available to recover the primary productivity and the system stability

  9. Variation in biochemical composition of Saccharina latissima and Laminaria digitata along an estuarine salinity gradient in inner Danish waters

    DEFF Research Database (Denmark)

    Nielsen, Mette Møller; Manns, Dirk Martin; D'Este, Martina

    2016-01-01

    In European kelp cultivation, knowledge on the spatial variation in biomass productivity and quality needs to be established. The present study provides a detailed overview of the biochemical composition and biomass production potential of Saccharina latissima and Laminaria digitata along...... a salinity gradient (16–31 PSU) in inner Danish waters. We discuss the results in a cultivation perspective, and evaluate the potential use of Laminariales as an energy feedstock, a feed additive and a bioremediation tool for mitigating eutrophication. We found the highest biomass production potential......, the highest protein content (7.5% of dry matter), and the highest capacity for bio-remediation of nitrogen (1.88% N of dry matter) at high salinities, as opposed to the highest concentrations of fermentable sugars (90% of dry matter) and pigments at low salinities. Thus, areas suitable for high biomass...

  10. Changes in the renal handling of urea in sheep on a low protein diet exposed to saline drinking water

    Directory of Open Access Journals (Sweden)

    R.A. Meintjes

    2004-11-01

    Full Text Available Previous trials have demonstrated that sheep on a low protein diet and free access to water, and sheep dosed with boluses of NaCl intraruminally also with free access to water, showed decreases in urea loss via the urine compared to control animals. We monitored urea excretion in sheep on a relatively poor protein diet when they were exposed to saline drinking water, i.e. they were unable to vary their intake of NaCl:water. Sheep on isotonic saline drinking water (phase 3 excreted significantly more urea via the urine (284 mM/day compared to phase 1 when they were on non-saline drinking water (urea excretion = 230 mM/day and phase 2 when they were on half isotonic saline drinking water (urea excretion = 244 mM/day.This finding was explained by the high glomerular filtration rate (GFR 91.9 ℓ/day, compared to 82.4 ℓ/day (phase 1 and 77.9 ℓ/day (phase 2, together with a significantly raised fractional excretion of urea (FEurea (51.1 % during this phase, and was in spite of the significantly lower plasma concentrations of urea in phase 3 compared to phase 1. The FEurea probably results from the osmotic diuresis caused by the salt. There were indications of a raised plasma antidiuretic hormone (ADH concentration and this would have opposed urea loss, as ADH promotes urea reabsorption. However, this ADH effect was probably counteracted to some extent by a low plasma angiotensin II concentration, for which again there were indications, inhibiting urea reabsorption during the phases of salt loading. As atrial natriuretic peptide both increases GFR and decrease sodium reabsorption from the tubule, it was probably instrumental in causing the increase in GFR and the increase in the fractional excretion of sodium (FENa.

  11. Salinization and dilution history of ground water discharging into the Sea of Galilee, the Dead Sea Transform, Israel

    International Nuclear Information System (INIS)

    Bergelson, G.; Nativ, R.; Bein, A.

    1999-01-01

    The mechanism governing salinization of ground water discharging into the Sea of Galilee in Israel has been the subject of debate for several decades. Because the lake provides 25% of the water consumed annually in Israel, correct identification of the salt sources is essential for the establishment of suitable water-management strategies for the lake and the ground water in the surrounding aquifers. Existing salinization models were evaluated in light of available and newly acquired data including general chemistry, and O, H, C and Cl isotopes. Based on the chemical and isotopic observations, the proposed salt source is an ancient, intensively evaporated brine (21- to 33-fold seawater) which percolated through the valley formations from a lake which had formed in the Rift Valley following seawater intrusion during the late Miocene. Low Na:Cl and high Br:Cl values support the extensive evaporation, whereas high Ca:Cl and low Mg:Cl values indicate the impact of dolomitization of the carbonate host rock on the residual solution. Based on radiocarbon and other isotope data, the dilution of the original brine occurred in two stages: the first took place similar30andpuncsp; omitted000 a ago by slightly evaporated fresh-to-brackish lake water to form the Sea of Galilee Brine. The second dilution phase is associated with the current hydrological regime as the Sea of Galilee Brine migrates upward along the Rift faults and mixes with the actively circulating fresh ground water to form the saline springs. The spatially variable chemical and isotopic features of the saline springs suggest not only differential dilution by fresh meteoric water, but also differential percolation timing of the original brine into the tectonically disconnected blocks, registering different evaporation stages in the original brine. Consequently, various operations to reduce the brine contribution to the lake may be differentially effective in the various areas. (Copyright (c) 1999 Elsevier Science

  12. Osmotic and ionic haemolymph concentrations in the Baltic Sea amphipod Gammarus oceanicus in relation to water salinity.

    Science.gov (United States)

    Normant, Monika; Kubicka, Magdalena; Lapucki, Tomasz; Czarnowski, Wojciech; Michalowska, Monika

    2005-05-01

    The aim of this work was to determine the osmotic and ionic (Na(+), K(+), Ca(2+), Mg(2+) and Cl(-)) haemolymph concentrations in Gammarus oceanicus at different salinity levels. Being a species of marine origin it inhabits brackish waters of the Baltic Sea. G. oceanicus specimens were collected in January 2003 from the Gulf of Gdansk (salinity 7 psu). The animals were gradually acclimated to eight different salinity levels (5, 7, 14, 20, 25, 30, 35 and 41 psu) at a temperature of 5 degrees C and 100% oxygen saturation. The haemolymph osmolalities correlated positively with external salinity, from 545.4+/-17.3 mOsm in 5 psu to 1185.9+/-34.6 mOsm in 41 psu. G. oceanicus hyperregulated within the 5-31.5 psu range; above 31.5 psu it hyporegulated its body fluids in comparison to the external medium. At 31.5 psu (1017 mOsm) the haemolymph concentration of G. oceanicus was isoosmotic with the habitat. The haemolymph concentrations of all the studied ions, except K(+), correlated positively with their concentrations at the various salinity.

  13. Tolerance of salinized floodplain conditions in a naturally occurring Eucalyptus hybrid related to lowered plant water potential.

    Science.gov (United States)

    Zubrinich, T M; Loveys, B; Gallasch, S; Seekamp, J V; Tyerman, S D

    2000-08-01

    Rising saline groundwater and reduced flooding frequency are causing dieback of Eucalyptus largiflorens F. Muell. along the Murray River in Australia. A green-leaved variant of E. largiflorens, which is probably a hybrid with a local mallee species (E. gracilis F. Muell.), tolerates saline conditions better than the more common grey-leaved variant. The green variant exhibited more negative water potentials than the grey variant, and comparison with soil water potential profiles indicated that the green variant extracted water from slightly higher up the soil profile where the salt content was lower but the soil was drier. However, the stable isotopes of water (2H and 18O) in the xylem did not differ significantly between paired green and grey trees, suggesting that both variants used the same water source. The green variant may be able to extract water for a longer period from a given point in the soil profile and tolerate a higher salt concentration around its roots than the grey variant. Predawn leaf water potentials of both variants decreased with increasing salinity of groundwater and decreasing depth to the groundwater, probably because the roots were being progressively confined to soil with lower matric potential as groundwater discharge through transpiration progressively salinized soil up the profile. The green variant had a lower assimilation rate and stomatal conductance than the grey variant, although the differences were not statistically significant during most of the year. Discrimination of 13C indicated that the green variant had a higher leaf internal CO2 concentration than the grey variant, indicative of a greater biochemical limitation on photosynthesis, perhaps resulting from the effects of operating at lower water potentials. The green variant had significantly lower stem hydraulic conductivity than the grey variant, probably because of its smaller xylem vessel diameter and higher degree of embolism. The more conservative water use of the green

  14. Effects of salinity, commercial salts, and water type on cultivation of the cryptophyte microalgae Rhodomonas salina and the calanoid Copepod Acartia tonsa

    DEFF Research Database (Denmark)

    Jepsen, Per Meyer; Thoisen, Christina V.; Carron-Cabaret, Thibaut

    2018-01-01

    at salinities of 10, 20, and 30 psu resulting in equal growth rates at salinities 20 and 30 in SW and RS mixed with deionized (DI) water. The optimum salinity for R. salina was 29 psu. For A. tonsa eggs, we observed highest hatching success in 30 psu with CP or RS mixed with DI water. The egg hatching success...... was not affected by salinities 15–40 and optimal hatching was obtained at 27 psu. Results confirm it was possible to use commercial salts for rearing of both R. salina and A. tonsa, widening the application of these species for aquaculture facilities without access to SW....

  15. [Effects of the grain size and thickness of dust deposits on soil water and salt movement in the hinterland of the Taklimakan Desert].

    Science.gov (United States)

    Sun, Yan-Wei; Li, Sheng-Yu; Xu, Xin-Wen; Zhang, Jian-Guo; Li, Ying

    2009-08-01

    By using mcirolysimeter, a laboratory simulation experiment was conducted to study the effects of the grain size and thickness of dust deposits on the soil water evaporation and salt movement in the hinterland of the Taklimakan Desert. Under the same initial soil water content and deposition thickness condition, finer-textured (soil water evaporation, deeper soil desiccation, and surface soil salt accumulation, while coarse-textured (0.063-2 mm) deposits inhibited soil water evaporation and decreased deeper soil water loss and surface soil salt accumulation. The inhibition effect of the grain size of dust deposits on soil water evaporation had an inflection point at the grain size 0.20 mm, i. e., increased with increasing grain size when the grain size was 0.063-0.20 mm but decreased with increasing grain size when the grain size was > 0.20 mm. With the increasing thickness of dust deposits, its inhibition effect on soil water evaporation increased, and there existed a logarithmic relationship between the dust deposits thickness and water evaporation. Surface soil salt accumulation had a negative correlation with dust deposits thickness. In sum, the dust deposits in study area could affect the stability of arid desert ecosystem.

  16. Aqueducts and geoglyphs : the response of Ancient Nasca to water shortages in the desert of Atacama (Peru)

    Science.gov (United States)

    Masini, Nicola; Lasaponara, Rosa

    2016-04-01

    The desert of Atacama is a plateau in South America, covering a 1,000-kilometre strip of land on the Pacific coast, west of the Andes mountains, between Chile and Peru. Due to the confluence of a cold ocean current (the Humboldt Current) along with other climatic factors, connected to the particular topography and geomorphology of the region, Atacama desert is one of the most arid areas of the world. In particular, in Nasca region (Southern Peru) the lack of water was (and still is) due to the following causes: (i) the scarce pluvial precipitations and the (ii) high infiltration capacity, and the consequent yearly significant reduction of the surface water (Schreiber & Lancho Rojas 2009). Over the millennia long periods of drought occurred and frequently the lack of water was persistent for several decades. Despite the arid and extreme nature of the environment, this region was populated by important civilizations, such as Paracas and Nasca, which flourished in the Early Intermediate period (200 BCE-500 AD) (Silvermann & Proulx 2002). In particular the Nasca civilization is well-known for its refined and colourful pottery, characterized by a rich icononographic repertory, and, above all, by the huge and mysterious geoglyphs drawn on the arid plateaus of the Rio Grande de Nasca Basin. In order to practice agriculture, the Nasca developed adequate strategies to cope with hostile environmental factors and water scarcity, building a very efficient aqueduct system. They were aided by the fact that underground water was likely enough close to the surface and accessible by constructing wells and underground aqueducts, known with quechua name of puquios (Schreiber & Lancho Rojas 2009; Lasaponara & Masini 2012a; 2012b) The effectiveness of the techniques of hydraulic engineering depended on the climate and the weather events that sometimes underwent drastic changes, as results of the cyclical phenomenon of El Niño Southern Oscillation (commonly called ENSO). Hence the

  17. Simulation and resistivity modeling of a geothermal reservoir with waters of different salinity

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, K.; Wilt, M.; Bodvarsson, G.S.; Goldstein, N.E.

    1982-10-01

    Apparent resistivities measured by means of repetitive dipole-dipole surveys show significant changes within the Cerro Prieto reservoir. The changes are attributed to production and natural recharge. To better understand the observed geophysical phenomena a simple reservoir simulation study combined with the appropriate DC resistivity calculations to determine the expected magnitude of apparent resistivity change. We consider production from a liquid-dominated reservoir with dimensions and parameters of the Cerro Prieto A reservoir and assume lateral and vertical recharge of colder and less saline waters. Based on rather schematic one- and two-dimensional reservoir simulations, we calculate changes in formation resistivity which we then transform into changes in apparent resistivity that would be observed at the surface. Simulated changes in apparent resistivities over the production zone show increases of 10 to 20% over a 3 year period at the current rate of fluid extraction. Changes of this magnitude are not only within our ability to discern using proper field techniques, but are consistent in magnitude with some of the observed effects. However, the patterns of apparent resistivity changes in the simulated dipole-dipole pseudosection only partially resemble the observed field data. This is explained by the fact that the actual fluid recharge into the A reservoir is more complicated than assumed in our simple, schematic recharge models.

  18. Mobility of trace metals associated with urban particles exposed to natural waters of various salinities from the Gironde Estuary, France

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, Joerg; Blanc, Gerard [Bordeaux Univ., Talence (France). UMR 5805 EPOC; Norra, Stefan [Karlsruhe Univ. (Germany). Inst. of Mineralogy and Geochemistry; Klein, Daniel [Bordeaux Univ., Talence (France). UMR 5805 EPOC; Karlsruhe Univ. (Germany). Inst. of Mineralogy and Geochemistry

    2009-08-15

    Background, aim and scope: Urban systems are hot spots of environmental pollution caused by manifold anthropogenic activities generating traffic-related, industrial and domestic emissions. Besides air, soil and groundwater pollution, pollution of surface water systems is of major concern because they are often (ab)used to export waste of various consistence out of urban areas and become contaminated on varying scales. The Gironde Estuary (southwest France) is affected by various anthropogenic contaminations derived from historic polymetallic pollution mainly due to former mining and ore-treatment and, additionally, from agriculture and urban areas. Although detailed knowledge is available on the impact of mining and anthropogenic activities on the water quality of the Gironde Estuary, almost nothing is known on the urban impact, even though the Garonne Branch which is one tributary of the Gironde system crosses the large urban agglomeration of Bordeaux. The present work links urban geochemistry and estuary research and aims at evaluating the mobility of potentially toxic trace elements (Cd, Cu, Zn, V, Co, Mo, Pb) associated with urban particles under estuarine conditions owing to the particles' role as potential vectors transporting urban pollutants into the estuary. For this, environmentally available fractions of trace elements in representative urban particles (urban dust, road sediment, riverbank sediment, construction materials) from the city of Bordeaux were extracted by natural estuarine waters of varying salinities and compared to commonly applied HNO{sub 3} extractions. Materials and methods: For the assessment of the urban particles' contribution to the pollution of the Gironde/Garonne system, various particle types were sampled in Bordeaux: road sediments, urban bulk deposition, construction materials (concrete, asphalt, tile and gravel) and flood sediments. Potentially environmental available fractions of Cd, Cu, Zn, V, Co, Mo and Pb were

  19. Water relations and foliar isotopic composition of Prosopis tamarugo Phil. an endemic tree of the Atacama Desert growing under three levels of water table depth.

    Directory of Open Access Journals (Sweden)

    Marco eGarrido

    2016-03-01

    Full Text Available Prosopis tamarugo Phil. is a strict phreatophyte tree species endemic to the Pampa del Tamarugal, Atacama Desert. The extraction of water for various uses has increased the depth of the water table in the Pampa aquifers threatening its conservation. This study aimed to determine the effect of the groundwater table depth on the water relations of P. tamarugo and to present thresholds of groundwater depth (GWD that can be used in the groundwater management of the P. tamarugo ecosystem. Three levels of GWD, 11.2 ± 0.3 m, 10.3 ± 0.3 m and 7.1 ± 0.1 m, (the last GWD being our reference were selected and groups of 4 individuals per GWD were studied in the months of January and July of the years 2011 through 2014. When the water table depth exceeded 10 m, P. tamarugo had lower pre-dawn and midday water potential but no differences were observed in minimum leaf stomatal resistance when compared to the condition of 7.1 m GWD; the leaf tissue increased its δ13C and δ18O composition. Furthermore, a smaller green canopy fraction of the trees and increased foliage loss in winter with increasing water table depth was observed. The differences observed in the physiological behavior of P. tamarugo trees, attributable to the ground water depth; show that increasing the depth of the water table from 7 to 11 m significantly affects the water status of P. tamarugo. The results indicate that P. tamarugo has an anisohydric stomatal behaviour and that given a reduction in water supply it regulates the water demand via foliage loss. The growth and leaf physiological activities are highly sensitive to GWD. The foliage loss appears to prevent the trees from reaching water potentials leading to complete loss of hydraulic functionality by cavitation. The balance achieved between water supply and demand was reflected in the low variation of the water potential and of the variables related to gas exchange over time for a given GWD. This acclimation capacity of P

  20. Decadal Salinity Changes in the Oceanic Subtropical Gyres and Connection to Changes in the Global Water Cycle

    Science.gov (United States)

    Melzer, Bryce Andrew

    There is evidence that the global water cycle has been undergoing an intensification over several decades as a response to increasing atmospheric temperatures, particularly in regions with skewed evaporation - precipitation (E-P) patterns such as the oceanic subtropical gyres. However, observational data (rain gauges, etc.) can be quite sparse over such areas due to the inaccessibility of open ocean regions. This study utilizes in situ data, reanalysis, and model outputs to infer interannual to decadal scale trends in surface freshwater forcing within remote, evaporation-dominated subtropical regions of the ocean as they pertain to the past and present state of the global water cycle. Emphasized in this study is the importance of utilizing a wide range of ocean parameters to strengthen and validate the inferences made from any one proxy of a given parameter. A positive trend in sea surface salinity in the subtropical gyres revealed evidence for decadal intensification in the surface forcing of these regions. Zonal drift in the location of the salinity maximum of the south Pacific, north Atlantic, and south Indian regions implies a change in the mean near-surface currents responsible for advecting high salinity waters into the region. Additionally, a comparison of satellite, in situ, and model salinity datasets was conducted to highlight the potential applications of Aquarius and SMOS satellite-derived salinity products over oceanic regions of low observational density. Spatial and temporal salinity trends in the five subtropical gyre regions were also analyzed over the past six decades, with a focus on the subsurface salinity of the upper 1000 m of the ocean. Our results indicate an overall salinity increase within the mixed layer, and a salinity decrease at depths greater than 200m in the global subtropical gyres over 61 years. Our analysis of decadal variability of depth-integrated mixed layer fluxes into and out of the gyres reveals little change in the strength

  1. Negative effects of salinity on water fleas: implications of saltwater intrusion on freshwater organisms

    Science.gov (United States)

    Reed, A.

    2017-12-01

    Saltwater intrusion can impact freshwater organisms. In this project, Daphnia were used to determine these impacts. I exposed Daphnia to four different treatments (A-C) of salinity for twenty-four hours, hypothesizing that only the control (D) Daphnia would survive. Average percent survival was 89% for D, 85% for C, 7% for B, and 0% for A. The percent survival increases as the salinity decreases. These results suggest that if Daphnia are exposed to a salinity of 5 ppt or higher, they probably will not survive.

  2. Arsenic concentrations correlate with salinity for fish taken from the North Sea and Baltic waters

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Francesconi, K. A.

    2003-01-01

    Total arsenic concentrations were determined in three teleost species (herring Clupea harengus; cod Gadus morhua, and flounder Platichthys flesus) taken. from four locations in the Baltic and North Sea with salinities ranging from 8 to 32 psu. Individual arsenic concentrations ranged from 0.......04 to 10.9 mg/kg wet mass, and there was a positive linear relationship between arsenic concentration and salinity for all three species (r(2) 0.44 to 0.72, all P arsenic than do freshwater fish, the data reported...... here are the first showing a relationship between the total arsenic concentration in fish and salinity....

  3. Effects of water salinity and nitrogen fertilization on the growth and yield of ‘BRS Gabriela’ castor beans

    Directory of Open Access Journals (Sweden)

    João Batista dos Santos

    2016-10-01

    Full Text Available The castor bean has attracted the attention of many farmers as an alternative crop for the National Program of Biofuel and its extensive use in the ricinochemical industry. The crop requires large planting areas to meet the demands of the fuel market. The aim of the present study was to evaluate the effects of irrigation water salinity and nitrogen fertilization on the growth and production of castor beans, ‘BRS Gabriela’, in a protected environment. The present study was conducted at the Center of Technology and Natural Resources of the Federal University of Campina Grande. The experimental design was completely randomized in a 5 × 4 factorial with three replications and one plant per plot. The treatments consisted of irrigation water with five electrical conductivity (ECw levels of 0.7, 1.7, 2.7, 3.7, and 4.7 dS m-1 associated with four nitrogen levels of 60, 80, 100, and 120 mg of N kg-1 of soil. The interaction between water salinity and nitrogen rates did not exert significant effects on the variables studied. Increased salinity of irrigation water affected the growth in height and stem diameter of castor beans in all periods, and leaf area from 90 days after sowing. Increased nitrogen levels had a positive effect on leaf area at 60, 90, 120, and 150 days after sowing. The total mass of seeds, one hundred seed mass, yield, and number of fruits per plant decreased with the increase in water salinity, and the total mass of seeds was the most affected variable.

  4. Functionally relevant climate variables for arid lands: Aclimatic water deficit approach for modelling desert shrub distributions

    Science.gov (United States)

    Thomas E. Dilts; Peter J. Weisberg; Camie M. Dencker; Jeanne C. Chambers

    2015-01-01

    We have three goals. (1) To develop a suite of functionally relevant climate variables for modelling vegetation distribution on arid and semi-arid landscapes of the Great Basin, USA. (2) To compare the predictive power of vegetation distribution models based on mechanistically proximate factors (water deficit variables) and factors that are more mechanistically removed...

  5. Evaluation of two hybrid poplar clones as constructed wetland plant species for treating saline water high in boron and selenium, or waters only high in boron

    Science.gov (United States)

    Wetland mesocosms were constructed to assess two salt- and B-tolerant hybrid poplar clones (Populus trichocarpa ×P. deltoides×P. nigra '345-1' and '347-14') for treating saline water high in boron (B) and selenium (Se). In addition, a hydroponic experiment was performed to test the B tolerance and B...

  6. Autonomous multi-sensor micro-system for measurement of ocean water salinity

    DEFF Research Database (Denmark)

    Hyldgård, Anders; Mortensen, Dennis; Birkelund, Karen

    2008-01-01

    This paper describes the design, fabrication and application of a micro-fabricated salinity sensor system. The theoretical electrochemical behaviour is described using electrical equivalent diagrams and simple scaling properties are investigated analytically and numerically using finite element...

  7. Enhanced Resolution for Aquarius Salinity Retrieval near Land-Water Boundaries

    Science.gov (United States)

    Utku, Cuneyt; Le Vine, David M.

    2014-01-01

    A numerical reconstruction of the brightness temperature is examined as a potential way to improve the retrieval of salinity from Aquarius measurements closer to landwater boundaries. A test case using simulated ocean-land scenes suggest promise for the technique.

  8. Linking fog water use by plants in the coastal Namib Desert to carbon and nitrogen cycles along aridity gradients

    Science.gov (United States)

    Macko, S. A.; Soderberg, K.; Henschel, J.; Billmark, K.; Swap, R. J.

    2009-12-01

    A steep rainfall gradient exists across the Namib Desert in southern Africa, which is unique in that frequent coastal fog occurs in areas that receive the least rainfall. Overall, the Namib is hyper-arid in terms of rainfall (25-100mm mean annual rainfall, MAR), but areas within about 60km of the coast see up to 100 days of fog each year. This scenario has influenced the distribution of plant species and the behavior of Namib fauna. In this study, carbon and nitrogen isotopes are used to investigate the biogeochemistry of vegetation the Namib aridity gradient, and fog uptake by individual plants is estimated by comparing water isotopes (δ2H and δ18O) of fog, groundwater, rain, soil water and plant water. Using the natural aridity gradient as a basis for this investigation allows for observation of patterns that can potentially be related to controlling biogeochemical processes. Studies of carbon and nitrogen isotopes in vegetation along precipitation gradients have revealed similar patterns in the Kalahari of southern Africa and in West Australia. The Kalahari trend observed along a precipitation gradient of 200-1000mm MAR shows enriched δ13C values in drier areas, and this trend is only apparent in C3 vegetation. The West Australia gradient (1000mm MAR) follows the same general pattern, but the values are quite variable below about 250mm MAR. The corresponding nitrogen isotope data in the Kalahari shows an enrichment in 15N with less rainfall, again only apparent in C3 vegetation. Although there are significant differences between the Namib and Kalahari setting - notably soils and climatology - the Namib aridity gradient could potentially extend the Kalahari data set to areas that receive less than 100mm MAR. The fog and the unique survival strategies of Namib plants may explain differences between the Namib and Kalahari patterns. For example, the C3/CAM species W. mirabilis has highly variable δ13C values (-17.5 to -24‰), with a slight enrichment

  9. Water quality assessment and flora study of desert thar and nagarparkar district tharparkar, sindh Pakistan

    International Nuclear Information System (INIS)

    Leghari, S.M.; Mahar, M.A.; Khuhawar, M.Y.; Jahangir, T.M.

    2007-01-01

    A number of water samples (24) were collected from wells, water pumps, natural and artificial depressions from Naukot, Vajuto, Mithi, Islamkot, Virawah and Nagarparkar area and analyzed on the site and at the laboratories for 18 different parameters. There was a wide variation in water quality; conductivity 157 to 41400 micro S/m and total dissolved solids 100 to 26500 mg/L. The highest values were observed at Virawah area and lowest at an artificial depression of rainwater within Nagarparkar town. The higher vegetation of Thar region consists mainly of thorny or prickly shrubs and perennial herbs capable of drought resistance as Calligonum polygonoides, Aerva javanica, Salvadora oleoides, Acacia senegal, Capparis decidua, Tamarix aphylla, Prosopis spicigera, Leptadenia pyrotechnica and Zizyphus nummularia. During rainy season when dunes are covered with grasses and other herbs Salvadora oleoides, Capparis decidua, and Tamarix aphylla were found scattered in Thar area. Acacia leucophloea, Acacia senegal, Salvadora oleoides, Commiphora mukul, Barleria prionitis, Blepharis sindica, Euphorbia caudicifolia were found on dry and rocky area. Rainwater pools contain total 83 algal sp; 37 sp belonging to Cyanophyta; 23 sp Volocothyta; 10 sp Chlorophyta; 3 sp Charophyta; 10 sp Bacillarophyta; some algal species found epiphytic on aquatic plants such as Chaetophora pisiformis, Stigeoclonium subsecundum, Oedogonium sp. Spirogyra rhizobrachialis, S. fluviatilis and Gloeotrichia natans attached to Najas minor, Nymphaea stellata, and Typha domingensis. (author)

  10. Jarosite Precipitation from Acidic Saline Waters in Kachchh, Gujarat, India: an Appropriate Martian Analogue?

    Science.gov (United States)

    Mitra, S.; Gupta, S.; Bhattacharya, S.; Banerjee, S.; Chauhan, P.; Parthasarathy, G.

    2014-12-01

    consistent association of jarosite-bearing horizons with gypsum in Kachchh indicate that saline water intrusion may have played an important role in its formation. Since this association is also reported from the Meridiani Planum, a model explaining the origin of jarosite formation in Kachchh may also be relevant for the Martian surface.

  11. Impact of fresh and saline water flooding on leaf gas exchange in two Italian provenances of Tamarix africana Poiret.

    Science.gov (United States)

    Abou Jaoudé, R; de Dato, G; Palmegiani, M; De Angelis, P

    2013-01-01

    In Mediterranean coastal areas, changes in precipitation patterns and seawater levels are leading to increased frequency of flooding and to salinization of estuaries and freshwater systems. Tamarix spp. are often the only woody species growing in such environments. These species are known for their tolerance to moderate salinity; however, contrasting information exists regarding their tolerance to flooding, and the combination of the two stresses has never been studied in Tamarix spp. Here, we analyse the photosynthetic responses of T. africana Poiret to temporary flooding (45 days) with fresh or saline water (200 mm) in two Italian provenances (Simeto and Baratz). The measurements were conducted before and after the onset of flooding, to test the possible cumulative effects of the treatments and effects on twig aging, and to analyse the responses of twigs formed during the experimental period. Full tolerance was evident in T. africana with respect to flooding with fresh water, which did not affect photosynthetic performances in either provenance. Saline flooding was differently tolerated by the two provenances. Moreover, salinity tolerance differently affected the two twig generations. In particular, a reduction in net assimilation rate (-48.8%) was only observed in Baratz twigs formed during the experimental period, compared to pre-existing twigs. This reduction was a consequence of non-stomatal limitations (maximum carboxylation rate and electron transport), probably as a result of higher Na transport to the twigs, coupled with reduced Na storage in the roots. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  12. Salinity-dependent toxicity of water-dispersible, single-walled carbon nanotubes to Japanese medaka embryos.

    Science.gov (United States)

    Kataoka, Chisato; Nakahara, Kousuke; Shimizu, Kaori; Kowase, Shinsuke; Nagasaka, Seiji; Ifuku, Shinsuke; Kashiwada, Shosaku

    2017-04-01

    To investigate the effects of salinity on the behavior and toxicity of functionalized single-walled carbon nanotubes (SWCNTs), which are chemical modified nanotube to increase dispersibility, medaka embryos were exposed to non-functionalized single-walled carbon nanotubes (N-SWCNTs), water-dispersible, cationic, plastic-polymer-coated, single-walled carbon nanotubes (W-SWCNTs), or hydrophobic polyethylene glycol-functionalized, single-walled carbon nanotubes (PEG-SWCNTs) at different salinities, from freshwater to seawater. As reference nanomaterials, we tested dispersible chitin nanofiber (CNF), chitosan-chitin nanofiber (CCNF) and chitin nanocrystal (CNC, i.e. shortened CNF). Under freshwater conditions, with exposure to 10 mg l -1  W-SWCNTs, the yolk sacks of 57.8% of embryos shrank, and the remaining embryos had a reduced heart rate, eye diameter and hatching rate. Larvae had severe defects of the spinal cord, membranous fin and tail formation. These toxic effects increased with increasing salinity. Survival rates declined with increasing salinity and reached 0.0% in seawater. In scanning electron microscope images, W-SWCNTs, CNF, CCNF and CNC were adsorbed densely over the egg chorion surface; however, because of chitin's biologically harmless properties, only W-SWCNTs had toxic effects on the medaka eggs. No toxicity was observed from N-SWCNT and PEG-SWCNT exposure. We demonstrated that water dispersibility, surface chemistry, biomedical properties and salinity were important factors in assessing the aquatic toxicity of nanomaterials. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Effect of Underground Saline Water on the Growth Characteristic of Tamarix austromongolica in Halomorphic Soil

    Science.gov (United States)

    Iwama, Kenji; Kobayashi, Koji; Kaneki, Ryoichi; Furukawa, Masayuki; Odani, Hiromichi

    It is important to evaluate the salt tolerance of native plants in order to utilize them for improving halomorphic soil in arid regions. Tamarix austromongolica, a dominant species in Inner Mongolia, China, has the property of salt absorption and expected soil desalinization. The effect of salt concentration in groundwater on the growth of stock diameter and shoot length were evaluated by cultivation experiments, growing the plants from cuttings for two years. Though the plants grew well in 1% salt concentration of groundwater, the evapotranspiration in the second year was reduced because of the growth of the root system. The growth of the plants and evapotranspiration were reduced with increasing groundwater salinity of 3 to 5%, but most plants did not die. In contrast, the plants which were supplied with groundwater of 7% salt concentration in the second year started to die in about a month, and two thirds of them died within five months. Thus the results showed that the tolerant limit of salinity of the plants in groundwater was 7%, and the growth was constrained with groundwater salinity of 3 to 5% concentration. The plants that survived with 7% salinity in the second year, however, were grown in groundwater salt concentration of 3% to 5% in the first year. This result indicated that saline stress might have changed the characteristic of salinity tolerance of the plant.

  14. Balanço hídrico e da salinidade do solo na bananeira irrigada com água de diferentes salinidades = Soil water and salinity balance on banana irrigated with water of varied salinity

    Directory of Open Access Journals (Sweden)

    Ancélio Ricardo de Oliveira Gondim

    2009-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de diferentes níveis de salinidade de água de irrigação no uso consultivo na fase reprodutiva da bananeira e evolução da salinidade do solo. Adotou-se o delineamento inteiramente casualizado em parcelas subdivididas, totalizando oito tratamentos com quatro repetições por tratamento. Os níveis de salinidade foram obtidos a partir de águas naturais de poços dos aquíferos arenito e calcário e foram misturadas em tanques de alvenaria para a obtenção das concentrações de salinidade desejada. Verificou-se que a área do bulbo com umidade superior a 8% representa aproximadamente 50% do volume do solo. A evapotranspiração da cultura diminuiu com o aumento da salinidade entre os tratamentos, o kc médio no período variou de 1,01 a 1,09 em águas de salinidade extremas. Comparando os perfis da salinidade do solo, verificou-se quea concentração de sais foi superior na camada superficial aos 440 dias após plantio.The objective this work was to evaluate the advisory use of two cultivars banana and the salinity of the soil in different water salinity levels (0.55; 1.70; 2.85; and 4.00 dS m-1 during the reproductive phase. The experimental design chosen was randomizedcomplete blocks in subdivided plots, totaling eight treatments with four repetitions per treatment. The salinity levels were obtained from natural waters of wells from sandstone and calcareous aquifers and were mixed in masonry tanks in order to obtain the desiredsalinity concentrations. It was verified that the area of the bulb with moisture greater than 8% represents approximately 50% of the volume of the soil. The evapotranspiration of the culture decreased with the increase in the salinity among the treatments; the average kc in the period varied from 1.01 to 1.09 in waters of extreme salinity. Comparing the salinity profiles of the soil, it was verified that the concentration of salts was highest on the surfacelayer at 440

  15. The nutrient, salinity, and stable oxygen isotope composition of Bering and Chukchi Seas waters in and near the Bering Strait

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, L.W. [Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee (United States)]|[Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville (United States); Whitledge, T.E. [Marine Science Institute, University of Texas at Austin (United States); Grebmeier, J.M. [Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville (United States)]|[Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee (United States); Weingartner, T. [Institute of Marine Science, University of Alaska Fairbanks (United States)

    1997-06-01

    Seawater nutrient, salinity, and oxygen 18 data collected from 1990 to 1993 in the Bering and Chukchi Seas were used to identify potential sources of nutrients and water masses that result in formation of the Arctic Ocean upper halocline and its associated nutrient maximum. Water matching the {delta}{sup 18}O values of the Arctic Ocean upper halocline and containing sufficient, or a nearly sufficient, nutrient and salinity concentration was collected in subsurface waters in the summer in portions of the Bering Sea, particularly the Gulf of Anadyr. However, nutrient concentrations significantly declined in this north flowing water over the shallow continental shelf before it reached the Bering Strait, as a consequence of biological utilization, and dilution with nutrient-poor and oxygen 18-depleted fresh water. Therefore it does not appear likely that the flow of unaltered water through the Bering Strait in the summer plays a critical role in the formation of the Arctic Ocean upper halocline. The role of other mechanisms for contributing Pacific-derived waters to the Arctic Ocean nutrient maximum is considered.{copyright} 1997 American Geophysical Union

  16. [Research advance in seed germination of desert woody plants].

    Science.gov (United States)

    Chang, Wei; Wu, Jian-guo; Liu, Yan-hong

    2007-02-01

    This paper reviewed the research methods of desert woody plants seed germination, and the effects of internal and external ecological factors on it. Most researchers use incubator and artificial climate chamber to dispose the seeds, while field investigation was few involved. Seed dormancy is the important physiological factor affecting germination, while seed size, mass and color are closely correlated with its maturity and vigor. The poor permeability of seed capsule is a barrier that restrains the germination, which can be weakened or eliminated by shaving, cutting, treating with low temperature, and dipping in chemical reagent, etc. Seed water content has a close correlation with its storage life and water-absorbing capability. Suitable temperature is the prerequisite of seed germination, while changing temperature can accelerate the germination. Soil moisture content is a limiting factor, while illumination is not so essential to the seed germination of most desert woody plants. Sand-burying plays an important role in the seed germination through regulating illumination, temperature, and soil moisture content. Salinity stress restrains the seed germination of desert woody plants observably. In further studies, the effects of multi-factors and the eco-physiological and molecular biological mechanisms of germination should be more concerned.

  17. Effects of manipulation of water and nitrogen regime on the water relations of the desert shrub Larrea tridentata.

    Science.gov (United States)

    Meinzer, F C; Sharifi, M R; Nilsen, E T; Rundel, P W

    1988-12-01

    Water and nitrogen regimes of Larrea tridentata shrubs growing in the field were manipulated during an annual cycle. Patterns of leaf water status, leaf water relations characteristics, and stomatal behavior were followed concurrently. Large variations in leaf water status in both irrigated and nonirrigated individuals were observed. Predawn and midday leaf water potentials of nonirrigated shrubs were lowest except when measurements had been preceded by significant rainfall. Despite the large seasonal variation in leaf water status, reasonably constant, high levels of turgor were maintained. Pressure-volume curve analysis suggested that changes in the bulk leaf osmotic potential at full turgor were small and that nearly all of the turgor adjustment was due to tissue elastic adjustment. The increase in tissue elasticity with increasing water deficit manifested itself as a decrease in the relative water content at zero turgor and as a decrease in the tissue bulk elastic modulus. Because of large hydration-induced displacement in the osmotic potential and relative water content at zero turgor, it was necessary to use shoots in their natural state of hydration for pressure-volume curve determinations. Large diurnal and seasonal differences in maximum stomatal conductance were observed, but could not easily be attributed to variations in leaf water potential or leaf water relations characteristics such as the turgor loss point. The single factor which seemed to account for most of the diurnal and seasonal differences in maximum stomatal conductance between individual shrubs was an index of soil/root/ shoot hydraulic resistance. Daily maximum stomatal conductance was found to decrease with increasing soil/root/ shoot hydraulic resistance. This pattern was most consistent if the hydraulic resistance calculation was based on an estimate of total canopy transpiration rather than the more commonly used transpiration per unit leaf area. The reasons for this are discussed. It

  18. Drinking Water Sodium and Elevated Blood Pressure of Healthy Pregnant Women in Salinity-Affected Coastal Areas.

    Science.gov (United States)

    Scheelbeek, Pauline F D; Khan, Aneire E; Mojumder, Sontosh; Elliott, Paul; Vineis, Paolo

    2016-08-01

    Coastal areas in Southeast Asia are experiencing high sodium concentrations in drinking water sources that are commonly consumed by local populations. Salinity problems caused by episodic cyclones and subsequent seawater inundations are likely (partly) related to climate change and further exacerbated by changes in upstream river flow and local land-use activities. Dietary (food) sodium plays an important role in the global burden of hypertensive disease. It remains unknown, however, if sodium in drinking water-rather than food-has similar effects on blood pressure and disease risk. In this study, we examined the effect of drinking water sodium on blood pressure of pregnant women: increases in blood pressure in this group could severely affect maternal and fetal health. Data on blood pressure, drinking water source, and personal, lifestyle, and environmental confounders was obtained from 701 normotensive pregnant women residing in coastal Bangladesh. Generalized linear mixed regression models were used to investigate association of systolic and diastolic blood pressure of these-otherwise healthy-women with their water source. After adjustment for confounders, drinkers of tube well and pond water (high saline sources) were found to have significantly higher average systolic (+4.85 and +3.62 mm Hg) and diastolic (+2.30 and +1.72 mm Hg) blood pressures than rainwater drinkers. Drinking water salinity problems are expected to exacerbate in the future, putting millions of coastal people-including pregnant women-at increased risk of hypertension and associated diseases. There is an urgent need to further explore the health risks associated to this understudied environmental health problem and feasibility of possible adaptation strategies. © 2016 American Heart Association, Inc.

  19. Environmental isotope study related to groundwater age, flow system and saline water origin in Quaternary aquifers of North China Plain

    International Nuclear Information System (INIS)

    Zhang Zhigan; Payne, B.R.

    1988-01-01

    An isotopic hydrology section across the North China Plain has been studied to investigate problems of groundwater age, flow system and saline water origin in a semi-arid pre-mountain artesian basin. Two local and one regional flow system along the section have been recognized. Turnover time of water for alluvial fan, shallow and regional systems are estimated to be the order of 10 2 , 10 3 , and 10 4 years respectively. Specific flow rates for the three systems have been calculated. Only less than 5 percent of flow from alluvial fan is drained by the regional flow system and the rest, in natural conditions, discharges at surface in the front edge of an alluvial fan and forms a groundwater discharge belt at a good distance away from the mountain foot. Developed in the alluvial plain and coastal plain areas the shallow flow system embraces a series of small local systems. Groundwater in these systems appears to be the salt carrier during continental salinization. It washes salt out of the recharge area and deep-occurred strata by circulating and carries it up to the surface in lowland areas. Consequently, in parallel with salinization at surface a desalinization process occurs at depth, which provides an additional explanation for the existing thick deep fresh water zone in most arid and semi-arid regions, where continental salting process is in progress. (author). 6 refs, 8 figs, 4 tabs

  20. Degree of mucosal coating on double contrast barium enema : comparison of distilled water and normal saline as a suspension

    International Nuclear Information System (INIS)

    Seo, Tae Seok; Lee, Dong Ho; Ko, Young Tae; Lim, Joo Won; Han, Tae Il; Kim, Hyoung Jung

    1997-01-01

    To evaluate the degree of mucosal coating on double contrast barium enema (DCBE), using barium suspension made with distilled water or normal saline Between June 1 and July 30, 1996, fifty-four patients prospectively underwent DCBE using 83% w/v(weight-to-volume) of barium suspension (room temperature, 24 deg C), which was made with 1,200mL of distilled water (Group 1;29cases) and normal saline (Group 2;25cases) per 1Kg of Solotop (Taejoon Pharmacy, Seoul, Korea). Bowel preparation and examination methods were the same in both groups, and four projections(erect view, supine view, both decubitus views) were taken. The mucosal coating was graded as excellent, good, ordinary, or poor by three radiologists working independently, and scored from 3 to 0. Significance was analyzed by t-test. Mean grading scores were 2.33±0.70 in group 1 and 1.56±0.99 in group 2 (P<0.003). When barium suspension made with distilled water was used, the degree of mucosal coating on DCBE was better than when the suspension was made with normal saline

  1. Localization of water channels in the skin of two species of desert toads, Anaxyrus (Bufo) punctatus and Incilius (Bufo) alvarius.

    Science.gov (United States)

    Shibata, Yuki; Takeuchi, Hiro-Aki; Hasegawa, Takahiro; Suzuki, Masakazu; Tanaka, Shigeyasu; Hillyard, Stanley D; Nagai, Takatoshi

    2011-09-01

    Anuran amphibians obtain water by osmosis across their ventral skin. A specialized region in the pelvic skin of semiterrestrial species, termed the seat patch, contains aquaporins (AQPs) that become inserted into the apical plasma membrane of the epidermis following stimulation by arginine vasotocin (AVT) to facilitate rehydration. Two AVT-stimulated AQPs, AQP-h2 and AQP-h3, have been identified in the epidermis of seat patch skin of the Japanese tree frog, Hyla japonica, and show a high degree of homology with those of bufonid species. We used antibodies raised against AQP-h2 and AQP-h3 to characterize the expression of homologous AQPs in the skin of two species of toads that inhabit arid desert regions of southwestern North America. Western blot analysis of proteins gave positive results for AQP-h2-like proteins in the pelvic skin and also the urinary bladder of Anaxyrus (Bufo) punctatus while AQP-h3-like proteins were found in extracts from the pelvic skin and the more anterior ventral skin, but not the urinary bladder. Immunohistochemical observations showed both AQP-h2- and AQP-h3-like proteins were present in the apical membrane of skin from the pelvic skin of hydrated and dehydrated A. punctatus. Further stimulation by AVT or isoproterenol treatment of living toads was not evident. In contrast, skin from hydrated Incilius (Bufo) alvarius showed very weak labeling of AQP-h2- and AQP-h3-like proteins and labeling turned intense following stimulation by AVT. These results are similar to those of tree frogs and toads that occupy mesic habitats and suggest this pattern of AQP expression is the result of phylogenetic factors shared by hylid and bufonid anurans.

  2. Effect of salinity and sediment characteristics on the sorption and desorption of perfluorooctane sulfonate at sediment-water interface

    International Nuclear Information System (INIS)

    You Chun; Jia Chengxia; Pan Gang

    2010-01-01

    This study investigated the influence of solution salinity, pH and the sediment characteristics on the sorption and desorption of perfluorooctane sulfonate (PFOS). The results showed that the sorption of PFOS onto sediment increased by a factor of 3 as the CaCl 2 concentration increased from 0.005 to 0.5 mol L -1 at pH 7.0, and nearly 6 at pH 8.0. Desorption hysteresis occurred over all salinity. The thermodynamic index of irreversibility (TII) values increased with increasing concentration of CaCl 2 . Maximum irreversibility was found in the sorption systems with CaCl 2 in the concentration of 0.5 mol L -1 . The results suggested that PFOS can be largely removed from the water with increasing sali