Showing papers on "Saline water published in 1975"

Stratified lake and oceanic brines: Salt movement and time limits of existence1

Abstract: Pronounced salt concentration gradients in five antarctic, arctic, and Pacific coastal lakes an be accounted for by diffusional transport of salt out of the deeper saline water layers. The computed values of the mean salt diffusion coefficients, based on the ages of salinity stratification, agree to within an order of magnitude with molecular diffusivities for four out of five lakes. This agreement suggests that no major mixing events occurred in the water column during the late historical stages of the lakes. Upper limit time estimates for the removal of most of the salt from the saline bottom layers range from 5,000 to 35,000 years, depending on lake depth. Historical records of deepening of the Great Bitter Lake owing to dissolution of a salt layer on the bottom suggest that dissolution was a diffusion controlled process. For the saline brines in the Red Sea Deeps, an assumption tllat they are transient structures leads to the following estimates of the time to mixing with Red Sea water: 103-10” years, if mixing takes place by diffusional transport of salt between the heavier and lighter brines, and lo”-10’ years, if salt diffuses from the brines upward. The geologically short range of times suggests that the possible recycling of evaporative brines through the deeper ocean could not affect the ocean water salinity for any- significant time intcgval. A stratified water column consisting of a denser saline layer below a fresher water layer, with neither external input nor removal of salt, would eventually become homogeneous owing to dispersal of salt by molecular or eddy diffusion. Thus, many stratified brine lakes and ocean basins, where composition or salinity gradients are pronounced, are likely to be in a transient state with respect to the distribution of dissolved species. The differences in salt concentration between the denser and lighter layers in natural bodies of water range from a few hundred milligrams per liter to the upper limits of hundreds of grams per liter in salt-saturated brines overlain by freshwater. Here we examine the vertical distribution of salt in a number of coastal brine lakes, arriving at the rates of salt transport through the water column, as well as the limiting estimates of the longevity of brine stratification. In some of the lakes we examine, the higher salinities of the deeper waters are related to entrapment of ocean water during the postglacial rise of the

Effects of Saline Water from North Dakota Lakes on Survival of Fathead Minnow (Pimephales promelas) Embryos and Sac Fry

Abstract: Eggs and sac fry of the fathead minnow (Pimephales promelas) were subjected in the laboratory to various dilutions of water obtained from four saline North Dakota lakes; three were sodium sulfate-, one a sodium chloride-type lake. In water from the latter, the percent of fertilized eggs surviving as sac fry for 5 days remained the same as the percent hatched: about 90% at treatment levels of 500 – 12,000 μmho and 68% in undiluted lake water of 18,000 μmho. In sodium sulfate-type water, however, about 92% of the fertilized eggs hatched at treatment levels of 500 up to only 6,000 μmho, with about 82% living as sac fry for 5 days in water from two of the lakes, and only about 54% living for 5 days in dilutions made from the most saline lake (lake water of 25,000 μmho). No sac fry survived for 5 days after hatching in sodium sulfate-type water of 12,000 μmho. From laboratory bioassays and field observations, we estimated sodium sulfate-type water exceeding 8,000 μmho during reproductive periods may decrease s...

Influence of water salinity on sheep performance while grazing on natural grassland and saltbush pastures

Abstract: Merino sheep grazing a semi-arid natural grassland were given water containing 0.0, 1.2, 1.6 or 2.0 per cent (w/v) soluble salts and similar sheep grazing on saltbush (Atriplex vesicaria) were given water containing 0.0, 0.8, 1.2 or 1.6 per cent soluble salts. The saline water was made up from sodium chloride and magnesium sulphate to give an ionic concentration similar to that occurring in natural underground waters. On grassland, 1.2 per cent saline water was without effect on the sheep, 1.6 per cent water reduced weight and wool growth in the first year and 2.0 per cent water reduced both wool growth and body weight by a significant amount. The effects were confined to the summer period of November to March. On saltbush, the results for four years were essentially similar to those for sheep on the grassland, although the effects of 1.2 per cent and 1.6 per cent saline waters were more pronounced. However, in the fifth year when drought conditions prevailed, the effects of both these treatments were more severe Water intakes were up to 1 lday-1 higher on the saline water treatments than on the fresh water, except when water intakes of the sheep on saltbush were high (7-11 lday-1) and then water salinity reduced water intakes. It was concluded that water salinities up to 1.2 per cent on grassland and 0.8 per cent on saltbush will not affect sheep productivity. Higher concentration (up to 1.6 per cent on grassland and 1.2 per cent on saltbush) can be used for adult sheep when forage conditions are good.

A geophysical investigation of saline water in the chalk of the South Coast of England

Abstract: Summary The Chalk on the South Coast of England between the rivers Adur and Ouse is in hydraulic continuity with the sea. Certain pumping stations up to 3.5 km from the shoreline have shown in the past abnormal chloride ion concentrations which have been considered to be due to seawater intrusion into the aquifer. Geophysical logging of boreholes especially drilled for the purpose close to the shoreline has confirmed the presence of saline water at various horizons, and has also shown diurnal variations in salinity due to the tide and seasonal variations related to infiltration and groundwater abstraction rates.

Classification and Management of Saline Seeps in Western North Dakota

Abstract: Saline seeps observed in western North Dakota can be classified into one of several general categories based on different geologic conditions. Present management practices lead to the formation of saline seeps and their growth. Suggestions are given for modification of these practices which may have a beneficial effect on control and abatement of seeps.

Treatment of saline water

Abstract: PURPOSE: To produce K and Na in the form of KCl and NaCl with high yield rate by means of simple method from saline water which is obtained from the sea water by electrodialysis method. COPYRIGHT: (C)1977,JPO&Japio