Showing papers on "Saline water published in 1987"

The seasonal intrusion of relatively saline water on the shelf off northern and central Namibia

Abstract: The movement of tropical, saline water onto the northern and central Namibian shelf in late summer and early autumn in the periods 1973–1974 and 1979–1986 is investigated. The strong intrusions in ...

Beneficial Aspects of Sea-Water Intrusion

Abstract: The Permo-Triassic sandstone aquifer of northwest England has been a major source of ground-water supply since the early 19th century. Between Liverpool and Manchester, ground-water resource development has led to a considerable lowering of the water level inland and intrusion of sea water from the Mersey Estuary and Manchester Ship Canal. As part of a detailed investigation of resource management, a two-dimensional finite-difference flow model was developed to represent aquifer behavior for the period 1840 to 1980. Subsequently, this model was used to predict the effects of implementing various management strategies over a 40-year period ending 2020. Results indicate that ground-water withdrawals have exceeded natural replenishment by an average of 100% during the past 50 years. In this time the potentiometric heads have responded remarkably slowly to the flow imbalance, a resilience that is largely attributed to the inflow of sea water at rates only marginally less than recharge from meteoric sources. Careful development of the fresh ground-water resources has minimized water quality problems along the estuary and ship canal, and the model clearly shows how controlled inflow of saline water can considerably enhance the recovery of fresh ground-water reserves. Difficulties arise only when excessive exploitation accelerates water quality deterioration. Model calculations indicate that inflow of saline water would continue for over 10 years following complete cessation of fresh ground-water production.

The alpha, beta, gamma of evaporation from saline water bodies

Abstract: Evaporation from a saline water body is less than that from a freshwater body because of two factors: a decrease in saturation vapor pressure and a partially compensating increase in water surface temperature. These factors are quantified by analyzing field data for eight evaporation pans containing solutions with different salinities and ionic compositions (extending the analysis of Salhotra et al. (1985)). A large saline lake (Dead Sea) is also analyzed using a one-dimensional numerical model with coupled heat, salt, water, and mechanical energy balances. Further, the use of experiments involving evaporation pans, to study the effect of salinity on lake evaporation, is discussed in light of the fact that the two water bodies have different wind speed functions and hence different temperature feedback effects. Finally, data on the direct measurement of the saturation vapor pressure from mixtures of Mediterranean and Dead Sea waters are presented and compared with results from the analyses of the evaporation pan data.

Stratiform copper deposits hosted by low-energy sediments; III, Aspects of metal transport

Abstract: The approximate compositions of closed basin saline waters that existed in probable source rocks of stratiform copper deposits hosted by low-energy sediments were derived by the simulated evaporation of dilute inflow waters from basalt and granite provenances. The saline water derived from dilute inflow water in the basalt provenance had a pH of 7.6 and was saturated with talc, dolomite, and gypsum. The saline water derived from dilute inflow water in the granite provenance had a pH of 7.7 and was saturated with quartz, calcite, talc, and gypsum. Both waters were 3 molal in chloride and were also saturated with hematite, fluorite, and fluorapatite. The waters probably represent likely end members in the compositional spectrum of metal-transporting waters which existed in the source rocks of the stratiform copper deposits. Copper and cobalt exhibit solubility maxima of 1,500 ppm or greater and 150 ppm, respectively, at oxygen fugacities in the range 10 (super -35) to 10 (super -55) bars. Lead solubility is similar in the two waters and is a maximum of 20 ppm at oxygen fugacities greater than 10 (super -60) bars. Zinc solubility is a maximum of 80 ppm in the basalt-derived saline water, and 20 ppm in the granite-derived saline water. Silver solubility is a maximum of 200 ppm at oxygen fugacities above 10 (super -35) bars. Barium and iron solubilities are less than 5 ppm. Abundances of copper, silver, and in some instances cobalt, in all common source rocks result in concentrations of these metals in the saline waters less than their saturation limits. Concentrations of barium, iron, lead, manganese, and zinc in the saline waters are limited by water composition rather than by abundance in source rocks. The high copper, cobalt, lead, and zinc solubilities are consistent with the hypothesis (Haynes, 1986a) that most sulfides in stratiform copper deposits hosted by low-energy clastic sediments are deposited within 50 cm of the sediment-water interface during bacterial sulfate reduction. Porosity and permeability constraints imposed by uncompacted analogs of ore-hosting sediments show that the copper contents of the metal-transporting waters must be greater than 100 ppm for formation of ore which grades 1 percent or more copper. The modeling demonstrates that the proposed waters are potentially effective metal transporters capable of forming stratiform copper ore when the prevailing oxygen fugacity is within the range 10 (super -35) to 10 (super -55) bars. The saline waters are capable of transporting at least 100 ppm copper, and therefore, are likely to produce copper ore under the porosity and permeability constraints imposed by the hypothesis.

Nitrate nutrition as a tool to reduce chloride toxicity in avocado

Abstract: SYNOPSIS Three levels of nitrate (2, 8 and 16 mMol) and four levels of chloride (2, 4, 8 and 16 mMol), in a complete factorial experiment, were given for two months to two avocado rootstocks, Mexican (salt-sensitive) and West Indian (salt-tolerant). An increase in the concentrations of nitrate in the irrigation solution reduced the Cl - content in the leaves and enhanced the ability of the avocado plant to use increasing concentrations of saline water. Good growth was obtained at 16 mMol Cl - in the presence of equimolar N03 concentration. The results of this study suggest that by raising the nitrate content in the irrigation water, the tolerance of avocado plants to salinity is increased.

Irrigation of lucerne with saline groundwater on a slowly permeable, duplex soil

Abstract: Lucerne was irrigated for three years on a slowly permeable, duplex soil, with saline water up to 2.4 dS m−1 without significant yield decline. Irrigation water of 4.5 dS m−1 significantly reduced yield. Lucerne yield was most closely related to the soil ECe of the 0–15 cm depth, rather than the total rootzone, and was described by; Relative yield=100−6.5 (ECe-2.1). While lucerne roots reached depths of at least 150 cm, approximately 80% of total root length was located in the 0–60 cm depth. Increasing salinity increased the plant concentrations of sodium and chloride, however, these changes were not closely related to changes in yield. Soil salinity increased with increasing salinity of the applied water. However, during the irrigation season water penetration and the accumulation of salt within the profile was predominantly restricted to the 0–60 cm depth. No portion of the applied irrigation water was available as a leaching fraction. Any leaching of salts to the watertable, particularly below 120 cm, was due to winter rainfall rather than the application of summer irrigation water. Ripping the soil to a depth of 75 cm increased water infiltration and resulted in increased crop yields, but did not significantly affect the crop relative yield-soil ECe relationship. From the results it is proposed that on the slowly permeable duplex soils, when watertable depth is controlled, management strategies for lucerne irrigated with saline water should be based on controlling the salinity of the shallow soil depths, to 60 cm.

Sources of Ground Water Salinization in Parts of West Texas

Abstract: Determination of chemical constituent ratios allows distinction between two salinization mechanisms responsible for shallow saline ground water and vegetative-kill areas in parts of west Texas. Mixing of deep-basin (high Cl) salt water and shallow (low Cl) ground water results in saline waters with relatively low Ca/Cl, Mg/Cl, SO44/ Cl, Br/Cl, and NO3/Cl ratios. In scattergrams of major chemical constituents vs. chloride, plots of these waters indicate trends with deep-basin brines as high Cl end members. Evaporation of ground water from a shallow water table, in contrast, results in saline water that has relatively high Ca/Cl, Mg/Cl, SO4/Cl, and Br/CL ratios. Trends indicated by plots of this water type do not coincide with trends indicated by plots of sampled brines. Leaching of soil nitrate in areas with a shallow water table accounts for high NO3 concentrations in shallow ground water.

Chronic toxicity of an environmental contaminant mixture to young (or larval) striped bass

Abstract: Larvae of striped bass (Morone saxatilis (Walbaum)) were exposed to a mixture of organic and inorganic contaminants in fresh well water and 2 g L−1 saline water for 30 days and in 5 g L−1 saline water for 90 days. Environmental concentrations (ECs) of organic and inorganic chemicals were estimated for the Chesapeake Bay area. Striped bass were exposed to the EC, 0.25 EC, 0.5 EC, 2 EC, 4 EC, and a solvent control to simulate potential conditions in their spawning and nursery habitats of the Chesapeake Bay. The sensitivities of striped bass as determined by survival depended on the characteristics of the exposure water. Larvae exposed in fresh well water were the most susceptible to the contaminant mixture; the 2 and 4 EC treatments caused significant (P:5 0.05) mortality within 30 days. In the 2 g L−1 salinity water, the 4 EC treatment caused significant mortality after 30 days of exposure. Larvae exposed to the contaminant mixture for 90 days in the 5 g L−1 saline water incurred significant mortality in the 2 and 4 EC treatments. We concluded that the age of the larvae, concentration of the contaminants, and salinity of the environment must be considered in evaluating the influence of environmental contaminants on the decline of striped bass along the east coast.

Hydrography of a hypersaline coastal lagoon in the Red Sea

Abstract: Temporal and spatial variations in salinity, temperature, oxygen and pH were studied in a coastal lagoon located on the eastern coast of the Red Sea during 11 cruises taken in the period from May 1983 through April 1984. The lagoon has an area of about 30 km2 and a maximum depth of about 3 m. The study showed that the water in the lagoon had a very high salinity that varied between 51‰ in February to 113‰ in October and was believed to reach higher values in summer. Rapid fluctuations in salinity were observed in the lagoon especially in positions near its mouth due to the daily exchange of water with the Red Sea accompanying the tides. During high tide, a layer of relatively cold and low salinity water from the Red Sea entered the lagoon and spread over its warmer and more saline water. This led to the existence of a strong vertical stratification in this shallow lagoon. During low tide, the subsurface warm and high salinity water was exposed resulting in the existence of one layer of water in the lagoon. Temporal variation of salinity was correlated with the monthly changes of the mean sea level of the Red Sea and with evaporation. Spatial variations in this property at any position in the lagoon depended upon its location from the mouth of the lagoon. Temperature variation was controlled by meteorological conditions in the region and by the volume of the water in the lagoon. The marine environment of this lagoon is under natural stress due to its high temperature and to the extreme fluctuations of its high salinity. This can be reduced by increasing the rate of exchange of water between the lagoon and the Red Sea.

Performance of Surface Aerators in Saline Pond Waters

Abstract: Although the solubility of oxygen in water decreases as salinity increases, the rate at which an aerator transfers oxygen to water is not affected by salinity. A method for predicting aerator performance in saline water ponds is presented.

Afforestation of Salt Affected Wasteland I-screening of Forest Tree Species of Madhya Pradesh for Salt Tolerance

Abstract: Germination studies on the seeds of four forest tree species viz. Dendrocalamus Strictus (Bamboo) of Betul and Amarkantak origin, Emblica officinalis (Awala) and Acacia auriculiformis (Australian Babul) were performed in different artificially prepared saline water of 3, 6, 9, 12 and 18 mmhos/cm electrical conductivity adjusted in Hoagland solution 1 by incorporating neutral salt, NaCl. Tap water was the control whose Electrical conductivity was .56 mmhos/cm and fresh Hoagland solution contained 1.76 mmhos/cm E.C. Germination data were subjected to statistically analysis with 7 treatments and 8 replications in factorial design. Eamtoo may tolerate higher salt concentration. Bamboo of Amarkantak origin may prove to be better In high salinity conditions, however the same may be very detrimental for the germination of Awala. Australian Babul may not fair well in salt affected conditions.

Marginal-water application in arid zones

Abstract: The intensified efforts to improve agricultural economy in arid zones is associated with increased demand for water. Scarcity of potable water has hightened the importance of marginal water in dry regions. Marginal water includes saline water, wastewater, and runoff water. These water sources differ in location in regards to the application site, quality, quantity, and stability of supply. Previous experience proved that each of the above alternative water sources can be used separately or in combination, for the economic benefit of the farmers.

Solar Desalination Techniques

Abstract: Adequate quality and reliability of driking water supply is a fundamental need of all people Without potable or fresh water (less than about 550 parts per million, ppm, of salt) there is no human life Industries and Agrigculture also need fresh water without which they can not function or thrive Water is therefore the key to man’s prosperity; it is intimately associated with the evolution, civilisation and destiny; hence it is aptly said that water is everybody’s business Fresh water which was obtained from rivers, lakes, and ponds is becoming scarce because of idustrialization and population explostion Moreover these potable water sources are being polluted constantly by industrial wastes and large amounts of sewage It is said that presently more than 2000 million people are not getting potable water which leads to many deseases and stops the development In the past, also the shortage of fresh water existed but it was confined to arid and semi—arid regions and regions where only brackish water was available But now due to industrialization and population rise, the shortage has come into prominence

Leaching of salts as affected by the method of water application and atmospheric evaporativity under shallow and saline water-table conditions

Abstract: Field studies on leaching a highly saline sandy loam soil having a shallow groundwater table showed that application of 150 mm water in two equal parts at 10 days interval had no distinct advantage over a single application of the whole amount. On the contrary, the surface-accumulated salts were displaced to a lesser extent and the salt peak remained at a shallower depth under split application, particularly during periods of high atmospheric evaporativity when the leached salts tended to move upward between successive water applications. A soil mulch created by shallow tillage reduced evaporation losses and curtailed upward movement of salts, resulting in nearly 10% increase in leaching efficiency. Significantly a small quantity of water (0·41 cm leaching water per unit soil depth) sufficed for 70% chloride removal, indicating that under the prevailing conditions a larger fraction of the pores contributed to the leaching process. A compact layer, having a bulk density of 1·69 g/cm 3 , at the soil surface, also appeared to be related to the higher leaching efficiency by maintaining a preponderance of unsaturated flow.

Ostracode Shells as Indicators of Thermal History

Abstract: Ostracode shells from 20 species were subjected to various temperatures and pressures (T-P) to mimic burial. For the first time with ostracodes, mineral mixtures, organic matter, and saline water were used to simulate sediments and pore fluids. Features developed that were diagnostic of narrow T-P ranges and sediment types . Alteration in quartz was used as a standard for comparison. The shell features were, at increments of 30°C and 100 atm, as follows: Tabulated data; refer to PDF file. Except for the rosettes, all features are seen on fossil ostracodes, although rosettes also are common in sediments. For each 100 atm less, an additional 15 to 30°C was needed to achieve the alteration listed for a given temperature. Seawater (35 ppt) retarded alteration and had to be 30°C warmer to produce features like those in distilled water. More saline water (70 ppt) enhanced alteration and had to be 60°C cooler to match results in pure water. An additional 60°C was needed with one clay (61% silica) to equal the effect of quartz at a given T-P; in another clay (51% silica) and in calcite, 90 and 90 to 120°C were needed, respectively. The alteration in sediment mixtures was predictable, and depended upon the proportion of silica. Temperature, sediment and pore water salinity were the major controls of alteration of ostracode shells. For interpretations, a resolution of about 15°C was possible, but smaller increments in experiments may give even better results.

Origin of Saline Springs in Cataract Canyon, Utah

Abstract: Stable isotopic data from springs issuing from the Honaker Trail Formation in Cataract Canyon indicate that the springs have a large component of meteoric water and a small component of older, more saline water. Ionic ratios suggest that salt dissolution accounts for the salinity in the springs. This water of salt dissolution may have come from discharge of Leadville Limestone water or, more likely, from discharge of water recharged in the Grabens of the Needles fault zone that migrated to the impermeable Paradox Formation and dissolved salt in transit to discharge in Cataract Canyon. The saline water probably does not represent a component of Honaker Trail or Elephant Canyon formation waters as they are found in the formations near Davis and Lavender Canyons located about 20 to 25 miles east of Cataract Canyon.

Production of electrically processed food and apparatus therefor

Abstract: PURPOSE:To enable the ripening and thermal sterilization of a food material at a high temperature, by submerging a raw food material in dilute saline water and electrifying the material under application of pressure to the saline water. CONSTITUTION:A raw food material A is submerged in dilute saline water B used as an electrically conductive medium and is electrified under application of pressure to the dilute saline water B. Even if the temperature of the saline water B is raised by this process, the generation of bubbles can be prevented because the boiling point of the dilute saline water B is raised by the pressure applied to the water. A definite quantity of electrical current can be smoothly passed through the raw food material A via the dilute saline water B to increase the temperature of the food to >=100 deg.C. A ripened and thermally sterilized electrically processed food can be produced by this process.

Irrigation with saline water

Abstract: The potential of the saline water for irrigation against the background of the world's food shortage is reviewed. It is shown that irrigation has improved food situation wherever it has been used. However, irrigation is always associated with salinity problems. Leaching techniques and drip irrigation suggest a partial solution for the problem. The objective of this paper is to review and examine additional solutions in order to increase the use of saline water for irrigation. A quantitative approach to further research on the use of saline water for irrigation is suggested. An analytical solution to the mass-balance equation of nutrients and salt in the soil, which includes a sink term for absorption by a plant, revealed some valuable derivatives, both for planning further research in irrigation with saline water and making decisions about fertilization and soil leaching throughout the growth period of a crop. Preliminary attempts to meaningfully increase the fertilization level of crops irrigated with saline water support the approach that was developed from one of the model's derivatives.

Optimal management of saline water tables in irrigated regions

Abstract: A computer model incorporates uncertainties about water tables and aquifers into irrigation management.

Minimizing the Impact of Salinity Intrusion Due to Sea Level Rise

Abstract: A rise in sea level will cause saline water to intrude up estuaries including those adjacent to aquifers with major pumping centers. During a drought a significant amount of saline estuary water can recharge certain aquifer systems. The objective of this study is to consider various response options that are appropriate to minimize the impact of the salinity intrusion into the Delaware Estuary and adjacent Potomac-Raritan-Magothy aquifer system (PRM) during a drought. Extraction wells and a combination of extraction and injection wells are considered during the drought period. The results indicate that the PRM can be adequately protected during a drought with an adequate short term water supply and delivery system.

Method and plant for obtaining fresh water from saline water

Abstract: In a distillation system for saline water with the final preheater (20) being heated by the off-gas heat from a gas turbine system (38), the off-gas is, before entry into the final preheater (20), cooled by mixing with water to a temperature which is low enough to prevent salt deposits and/or encrustation on the heating surfaces contacted by the saline water.

Method for treating edible meat or raw fish with cold saline water and apparatus therefor

Abstract: PURPOSE:To enable water-washing and cold saline-water treatment of edible meat, etc., without necessitating an additional space, by continuously and successively subjecting edible meat, etc., in a container to washing with water, primary draining, spray of cold saline water, secondary draining and air-blasting. CONSTITUTION:Edible meat or raw fish is put into a container C and transferred by a conveyor B. The container C is successively and continuously sprayed with washing water by spray pipes 1, 2, sprayed with cold saline water by spray pipes 6, 6' and blasted with air by pipes b, b' attached to a frame A. The above pipes are supplied with water and air by tanks 3, 7, circulation pumps P1-P2 and a blower BL. The edible meat or raw fish contained in the container C is washed with water in a water-washing step X, drained in primary draining step Y1, sprayed with cold saline water from above and below, drained in secondary draining step Y2 and blasted with air in air-blasting step. The washing of edible meat or raw fish with water and the cold saline water treatment of the meat, etc., can be continuously carried out by the above apparatus without necessitating additional space.

Conjunctive use of surface and groundwater in a problem of environmental protection: a case in salento peninsula in southern italy

Abstract: The Ionic area of Apulia, in Southern Italy, has a very peculiar surface hydrology. The average annual rainfall is merely 500 mm, which gives rise to very little runoff. Groundwater resources are extensive and are favoured by natural recharge through the fractured soil. The groundwater system consists of a lens-shaped freshwater layer floating on top of intruded sea water. A multifaceted economic development plan has been formulated for this area by local and national authorities. However, the problems of environmental protection are related to the construction and operation of urban and industrial wastewater treatment plants. Extracted groundwater is mixed with brackish water from a coastal spring that has a flow of about 2 m3/s and with diversion of 2.4 m3/s from a large aqueduct system, starting from a reservoir more than 200 km away. This quantity of water is requested for irrigating an area on the order of 20,500 hectares. For this system an ‘incident’ is any situation in which a discharge of contaminated water, either onto the topsoil or below ground, is characterized by quality parameters that exceed acceptable limits. A secondary set of incidents can be defined if there is not enough water available to meet the demand for the most common uses. The situation in which the farmers have no water for irrigation is particularly serious, especially when the level of the water table is lowered or the piezometric surface of the saline water has risen.