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Search Results: 1 - 10 of 1498 matches for " salinity "
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Hydrochemistry as Indicator to Select the Suitable Locations for Water Storage in Tharthar Valley, Al-Jazira Area, Iraq  [PDF]
Sabbar Abdullah Salih, Lafta Salman Kadim, Manzor Qadir
Journal of Water Resource and Protection (JWARP) , 2012, DOI: 10.4236/jwarp.2012.48075
Abstract: Four locations were chosen according to geomorphologic and engineering criterion to store the water on the midstream of Tharthar valley, water samples were collected from the four locations to evaluate the hydrochemical properties as indicator to select the more suitable location, these locations are Hatra, Abu-Hamam, Tlol Al-Baj and Al-Sukkariah from the north to the south respectively. Also, the groundwater samples were collected from two shallow wells on the banks. The samples were analyzed to determine the concentrations of most common anions and cations in the water Ca2+, Mg2+, Na+, K+, CO32-, HCO3-, Cl, SO42+. Also, pH, EC and TDS were measured. The results reflect high variations in concentrations of the soluble materials, the concentrations of these components are highly increased in locations of Tlol Al-Baj and Al-Sukkariah in comparison with the locations of Hatra and Abu-Hamam. The variation in geology of the area along the valley was represented a main role on the quality of water. These results can help to select the suitable locations of small dam (dams) to store the water in the valley and prevent the problem of salinity. According to the results, the northern part of midstream (north of Abu-Hamam) is suitable for water storage and the dam construction. While the locations of the downstream enriched by local sources of salts.
Underground water affects sexual behavior and gene expression of hormones related to reproduction in blue gourami males  [PDF]
Gad Degani, Gal Levy
Advances in Biological Chemistry (ABC) , 2013, DOI: 10.4236/abc.2013.31016
Abstract:

This study examined the effect of underground water on reproduction- and growth-related hormones in blue gourami males under non-reproductive and reproductive conditions. An increase in the percentage of males building nests under the highest percentage of underground water were compared to fish that maintained a lower percentage of underground water in the first two days. The % Gonado-somatic index (GSI) of males building nests was higher than non- reproductively active males in water containing the lowest concentration of underground water. In non- reproductively active males, brain gonadotropin releasing hormone 1 (GnRH1) and pituitary β subunit of gonadotropins (GtHs) and prolactin (PRL) mRNA levels were significantly higher in males maintained in underground water. In reproductively active males, mRNA levels of brain GnRH1, gonadotropin releasing hormone 3 (GnRH3) and pituitary PRL mRNA levels were significantly higher than males maintained in underground water. Thus, it is suggested that underground water with high salinity and conductivity levels affects the gene expression of repro- duction-related hormones; in reproductively active males, it shortened the duration of nest-building by blue gourami males.

Efficiency of Nanofiltration Membrane TFC-SR3 and SelRo MPF-34 for Partial Elimination of Fluoride and Salinity from Drinking Water  [PDF]
Mouhamadou A. Diallo, Saidou N. Diop, Mohamad M. Diémé, Courfia K. Diawara
Journal of Water Resource and Protection (JWARP) , 2015, DOI: 10.4236/jwarp.2015.77043
Abstract: Consumption of safe drinking water is essential to human health. The excess of certain elements in drinking water causes health problem for people consuming these waters. In Senegal, the excessive levels of fluoride and salts found in the groundnut basin cause public health problem such as dental and/or skeletal fluorosis. Thus, the treatment of such waters is essential before consumption to prevent health problems. For a partial removal of fluoride and salinity, we tested the performance of two commercial nanofiltration membranes namely TFC-SR3 and SelRO MPF-34 at laboratory scale. The results showed that TFC-SR3 membrane was very efficient with rejection rates of 83% - 96% for fluoride ions and 89% - 96% for salinity. For SelRo MPF-34 membrane, retention rates of 25% - 52% were obtained for fluoride ions and 24% - 60% for the salinity.
A Review on Modeling of Kinneret Salinity with Practical Recommendations  [PDF]
Moshe Gophen
Open Journal of Modern Hydrology (OJMH) , 2016, DOI: 10.4236/ojmh.2016.63011
Abstract: Two models have been developed for the evaluation and prediction of salinity changes (chloride concentration; ppm; [Cl]) in Lake Kinneret. They are: 1) RM, which is based on the Salt balance and hydrological budget of the lake; 2) GM which is based on the geo-hydrological regional properties of Kinneret’s geological structure. The concept of both is partly different: RM is correlating reduction of runoffs to salinity elevation and GM relates salt flux to the aquifer yield and the impact of lake water level is neglected. Long term statistical analyses justify support to GM, excluding conditions of heavy floods. This paper is a combination of a supplemental extended temporal study and a models review. Practical conclusions on Kinneret hydrological management within a frame of constrains aimed at prevention of salinity and eutrophication increase are presented.
Soil Salinity Mapping and Monitoring in Arid and Semi-Arid Regions Using Remote Sensing Technology: A Review  [PDF]
Amal Allbed, Lalit Kumar
Advances in Remote Sensing (ARS) , 2013, DOI: 10.4236/ars.2013.24040
Abstract:

Soil salinity is a serious environmental problem especially in arid and semiarid areas. It either occurs naturally or is human-induced. High levels of soil salinity negatively affect crop growth and productivity leading land degradation ultimately. Thus, it is important to monitor and map soil salinity at an early stage to enact effective soil reclamation program that helps lessen or prevent future increase in soil salinity. Remote sensing has outperformed the traditional method for assessing soil salinity offering more informative and professional rapid assessment techniques for monitoring and mapping soil salinity. Soil salinity can be identified from remote sensing data obtained by different sensors by way of direct indicators that refer to salt features that are visible at the soil surface as well as indirect indicators such as the presence of halophytic plant and assessing the performance level of salt-tolerant crops. The purposes of this paper are to 1) discuss some soil salinity indicators; 2) review the satellite sensors and methods used for remote monitoring, detecting and mapping of soil salinity, particularly in arid and semi-arid regions; 3) review various spectral vegetation and salinity indices that have been developed and proposed for soil salinity detection and mapping, with an emphasis on soil salinity mapping and assessment in arid and semi-arid regions; and 4) highlight the most important issues limiting the use of remote sensing for soil salinity mapping, particularly in arid and semi-arid regions.

Salinity Effects on Development and Productivity of Crambe (Crambe abyssinica) under Greenhouse Conditions  [PDF]
Ana Carolina F. de Vasconcelos, Lúcia Helena G. Chaves, Felipe G. Souza, Hans R. Gheyi, Josely D. Fernandes
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.67091
Abstract: Salinity in soil or water in arid and semi arid regions can severely limit crop production, since the high amount of NaCl contributes to specific ion effects of Cl-, Na+ or both, and to antagonistic effects on nutrient elements. Affected by salt stress, most of the cultivated plants do not fully express their growth potential, which lowers their economic value. Crambe (Crambe abyssinica) is an oil plant of the cruciferous family and it is believed that crambe has great potential to figure as raw material for biofuel; however, literature is not abundant about the effects of salinity in crambe production. This work was carried out in order to evaluate the effects on the development and productivity of crambe irrigated with saline waters under greenhouse conditions. Treatments resulted from the combination of two factors: salinity of irrigation water (ECw) in five levels (1.03-control, 2.5, 4.0, 5.5, and 7.0 dS·m-1) and two types of salts (NaCl and NaCl + CaCl2) with three replications, totaling 30 experimental plots. At the end of the experimental period, soil samples from each plot were collected for chemical and salinity of soil saturation extract analyzes. Salt types did not affect plant parameters. However, the salinity levels presented significant effects on the all plant parameters, decreasing their values with the increase of the salt dose. Salinity levels of the solutions used for irrigation in this study affected the growth of plants and grain yield of crambe. Regarding the type of salts, a higher concentration of Na was observed for NaCl solutions at 2.5, 4.0 and 5.5 dS·m-1 salinity levels.
Electromagnetic and Optical Methods for Measurements of Salt Concentration of Water  [PDF]
?. A. Tengesdal, B. L. Hauge, L. E. Helseth
Journal of Electromagnetic Analysis and Applications (JEMAA) , 2014, DOI: 10.4236/jemaa.2014.66013
Abstract:

Sensors for monitoring the salinity of water are useful tools in both environmental sciences and chemical engineering. Sensors based on a large variety of principles have been developed. Here we describe the design and testing of two different, noninvasive measurement methods for monitoring the salt concentration of water. The first method is based measurements of the refractive index using a folded-path optical refractometer, while the second utilizes an electromagnetic resonator, consisting of a magnetic coil and a capacitor, which is brought to resonance by an external magnetic field source. It is demonstrated that the folded-path optical refractometer allows one to monitor changes in salt concentration down to 1 mM in the range between 0 and 0.7 M, whereas the electromagnetic resonator has the capability of monitoring concentration changes as small as 0.3 mM over the more limited range between 0 and 5 mM.

The Diversity of Chrysophycean Algae in an Arctic Zone of River and Sea Water Mixing, Russia  [PDF]
Alena D. Firsova, Anna Yu Bessudova, Larisa M. Sorokovikova, Irina V. Tomberg, Yelena V. Likhoshway
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.615246
Abstract: According to the results of studies in the region of lower Yenisei River to the Kara Sea shelf in September 2009, the flora of chrysophyte algae in the zone of river and sea water mixing comprises 43 species of the classes Chrysophyceae and Synurophyceae. Most of them are cosmopolitan and widespread, but four rare species have also been recorded. The most frequent species are Synura petersenii f. petersenii, S. petersenii f. kufferathii, Spiniferomonas takahashii, Mallomonas acaroides, and M. crassisquama. The composition of chrysophyte flora in the study region is similar to that in some lakes of the Taimyr Peninsula. It has been found that the diversity of chrysophytes in the zone of river and sea water mixing depends on water salinity, with a group of species occurring at increased salinity levels. It includes Chrysosphaerella coronacircumspina (5.2‰), Kephyrion spirale (5.2‰) and Mallomonas crassisquama (8‰). These data contribute to knowledge of how the distribution of chrysophytes responds to changes in ecological conditions such as water salinity, turbidity, pH, and concentrations of oxygen and mineral phosphorus.
Effect of Salts Stress on the Growth and Yield of Wheat (Triticum aestivum L.)  [PDF]
Niaz Ahmed Kalhoro, Inayatullah Rajpar, Shahmir Ali Kalhoro, Amjad Ali, Sajjad Raza, Muneer Ahmed, Fahad Ali Kalhoro, Muhammad Ramzan, Fazli Wahid
American Journal of Plant Sciences (AJPS) , 2016, DOI: 10.4236/ajps.2016.715199
Abstract: In order to study the effect of salts stress on the growth and yield of wheat (cv. Inqalab), a pot experiment was conducted in the wire-house of the Department of Soil Science, Sindh Agriculture University Tando Jam. The soil was artificially salinized to a range of salinity levels i.e . EC 2.16, 4.0, 6.0, 8.0 and 10.0 dS·m-1 with different salts (MgCl2 + CaCl2 + Na2SO4). The salinized soil used for the experiment was sandy clay in texture, alkaline in reaction (pH > 7.0) and moderate in organic matter (0.95%) content. The results showed that with increasing salinity there was an increase in the ECe, Na+, Ca2+, Mg2+ and Cl- and decrease in the K+, SAR and ESP values of the soil Increasing salinity, progressively decreased plant height, spike length, number of spikelets spike-1 1000 grain weight and yield (straw and grain). Adverse effects of salts on plants were associated with the accumulation of less K+ and more Na+ and Cl- in their flag leaf sap, grains and straw. This resulted in lower K+:5Na+ ratio in flag leaf sap, grains and straw of wheat plants. These results indicated that the effects of salts stress were greater at 10 than at 8, 6 and 4 EC dS·m-1.
Adaptabilidad ecofisiológica de organismos acuáticos tropicales a cambios de salinidad
Chung,Kyung S.;
Revista de Biología Tropical , 2001,
Abstract: physiological response of tropical organisms to salinity changes was studied for some marine, estuarine and freshwater fishes (astyanax bimaculatus, petenia karussii, cyprinodon dearborni, and oreochromis mossambicus), marine and freshwater crustaceans (penaeus brasiliensis, penaeus schmitti and macrobrachium carcinus), and marine bivalves (perna perna, crassostrea rhizophorae, and arca zebra) collected from northeast venezuela. they were acclimated for four weeks at various salinities, and (1) placed at high salinities to determine mean lethal salinity, (2) tested by increasing salinity 5 ? per day to define upper lethal salinity tolerance limit, or (3) observed in a saline gradient tank to determine salinity preference. acclimation level was the most significant factor. this phenomenon is important for tropical aquatic organisms in shallow waters, where they can adapt to high salinity during the dry season and cannot lose their acclimation level at low salinity during abrupt rain. for saline adaptation of tropical organisms, this behavior will contribute to their proliferation and distribution in fluctuating salinity environments.
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