Lake liming

Andersson P, Borg H, Kaerrhage P. 1995. Mercury in fish muscle in acidified and limed lakes. Water Air Soil Pollut 80 889-892. 

Anderson, M.R., D.A. Scruton, U.P. Williams, and J.F. Payne. 1995. Mercury in fish in the Smallwood Reservoir, Labrador, twenty one years after impoundment. Water Air Soil Pollut. 80 927-930. Andersson, P., H. Borg, and P. Karrhage. 1995. Mercury in fish muscle in acidified and limed lakes. Water Air Soil Pollut. 80 889-892. 

The lime lake remaining behind may contain alizarin, anthrapurpurin and flavopurpurin. It is treated with dilute hydrochloric acid and then shaken with ether, which dissolves these colouring matters, the ethereal layer being separated and evaporated and the residue dried at ioo° and weighed. 

Pure -nitroabzarin forms orange-yellow needles, which melt at 244°, with partial decomposition [19]. It sublimes in yellow leaflets, undergoing partial decomposition. It dissolves in benzene and glacial acetic acid, and gives a purple-red solution with alkalies. The violet lime-lake is not decomposed by carbonic acid. (Distinction from alizarin.) It forms a diacetyl compound, M.P. 218° [19]. Nitroalizarin dyes orange shades on alumina mordants, and reddish-violet on iron mordants. 

The above is a commercial green dyestuff prepared from the bark of various species of Bhamnus Rhamnus uHlis,Rh. chlorophlorus). It consists chiefly of the alumina and lime lakes of the glucoside. 

Calcium oxide is often used to lime lake waters that have been acidified by acid rain. It reacts with and neutralizes acids in the lake formed when nitric and sulfuric acid in acid rain are carried to earth by rain, snow, sleet, and other forms of precipitation. 

SCHOFIELD The state has been practicing liming lakes for the purpose of maintaining fish populations as far back as the 1950 s. It s only been I d say in the last five years that they organized programs developed specifically to address the problem of acid precipitation. 

Synthetic magnesia is most often produced from seawater, known as seawater magnesia. Seawater contains approximately 1294 ppm Mg. Synthetic magnesia can also be produced from brine wells or lakes which have much higher concentrations of magnesium. Regardless of the source of magnesium, the sea or brine water is treated with hydrated lime, Ca(OH)2, that precipitates Mg(OH)2 ... 

Controlling the effects of acid deposition by the use oflime or other acid-neutralizing compounds has been tried, but mainly on an experimental basis. Adding lime to lakes usually has only a short-term effect in terms of neutralizing lake acidity. The longevity of the effect is directly related to lake s... 

The low pH of acid precipitation can destroy forests and kill fish. Some lakes and streams lie in soil that has the natural ability to buffer the increased acidity of acid rain, usually because the soil contains a high amount of lime. Other lakes and streams, however, have no such buffering capacity. The pH of the water is not the main problem—at least not directly. The problem lies in the amount of aluminum compounds that are leached out of the soil surrounding the lake or stream at lower pHs. Aluminum is toxic to many aquatic species. 

In areas where lakes are particularly acidic, people have tried to neutralize the acid in the lakes by adding powdered lime (calcium oxide). Making a lake too alkaline, however, can be equally harmful to aquatic plants and animals, and determining the safe amount of lime to add is a difficult problem. 

The main source of silica in antiquity, as today, was sand and, very occasionally, crushed rock or pebbles. The most common modifier was soda, which was obtained from natron lakes, as in ancient Egypt, for example, or from vegetable ash. Most lime was derived from limestone, although some lime could also enter the mixture of glass raw materials together with soda... 

Sloan, R. and C.L. Schofield. 1983. Mercury levels in brook trout (Salvelinus fontinalis) from selected acid and limed Adirondack lakes. Northeast. Environ. Sci. 2 165-170. 

The detrimental effects of acid rain are a major reason why legislation such as the Clean Air Act places strict limitations on sulfur and nitrogen emissions. It is also a reason why low sulfur coal is preferred over high sulfur coal. To reduce sulfur dioxide emissions, industry also uses a technique call scrubbing. Industrial scrubbers employ a variety of physical and chemical processes to remove sulfur dioxide from emissions. Another technique used to combat acidification of lakes is to treat these systems with lime. The lime acts to neutralize the acid, but such techniques are usually costly and are only a temporary remedy for combating the problem. 

Liming an acidic lake is similar to the process many people use to maintain a pH balance in their soil for lawn maintenance. Plants have an optimum pH range in which they strive. Acidic conditions often develop in soils for several reasons. Rain tends to leach away basic ions, weak organic acids develop from the carbon dioxide produced by decaying organic matter, and strong acids, such as nitric acid, can form when ammonium fertilizers oxidize. To neutralize these acids, different forms of lime such as quicklime, CaO, and slaked lime, Ca(OH)2, are used to neutralize the acid and increase the pH of the soil. Table 13.9 shows how much fertilizer is wasted when applied to... 

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