Nitrogen in rain

Quantification in the contribution to sulphur and nitrogen in rain by the above processes has been summarized in table III. 

Table III - Processes contributing to the sulphur and nitrogen in rain. ...

JACOBSON Yes. We did that for the soybean experiment by applying fertilizer according to information that we obtained about what one should do for soybeans in this particular soil. The amount of sulfur that one applies in fertilizer is far in excess of sulfur deposited in an equivalent land area in a single rain event. However, rain events occur repeatedly over the course of a growing season and supply sulfur to the soil as well as directly to the foliage in a very dilute form. By comparing these two very different situations, one can develop an opinion that the sulfur or nitrogen in rain is totally irrelevant as far as plant nutrition is concerned to one where it is possible that it has some importance because of the different mode and pattern of application. 

Acid deposition occurs when sulfur dioxide and nitrogen oxide emissions are transformed in the atmosphere and return to the earth in rain, fog or snow. Approximately 20 million tons of SOj are emitted annually in the United States, mostly from the burning of fossil fuels by electric utilities. Acid rain damages lakes, harms forests and buildings, contributes to reduced visibility, and is suspected of damaging health. 

Nitric acid occurs naturally, in traces, in the atmosphere in rain w from the electrical discharge of lightning and from nuclear expins. Indeed, the natural nitrates of the world have probably been formed by the action of naturally occurring nitric acid to the extent of 4-6 lbs of combined nitrogen per acre (Ref 30)... 

Acid rain. Lakes in some areas of the world are now registering very low pH s because of excess acidity in rain. This was first noticed in Scandinavia and is now prevalent in eastern Canada and the northeastern U.S. Normal rainfall is 5.6 (because of CO2 in the air forming H2CO3). However, excessive use of fossil fuels (especially coal) with high sulfur and nitrogen content cause sulfuric and nitric acids in the atmosphere from the sulfur dioxide and nitrogen oxide products of combustion. Some rain in the Adirondack Mountains of upper New York State has been measured with a pH of 3.0. This problem is not specific to the chemical industry but should be of concern to all of us. 

A nitrogen regulator has to be set at 8 p.s.i. to achieve a pressure sufficient to maintain a flow rate of 0.5 in/rain. A slower flow rate results in poor resolution. 

England 0-97 mgrm. per litre of rain in the oountry, and 5-14 mgrms. in the towns and in Scotland, 0-53 mgrm. in the country, and 3-81 mgrms. in the town. Table V shows that ammoniacal nitrogen is usually in excess of nitric nitrogen, but the converse is true of tropical countries. The ammonia is usually collected by the acids—nitric, hydrochloric, or sulphuric—in the atmosphere and. carried to earth in rain or snow. 

Oxides of nitrogen and sulfur occur in the gaseous state in the atmosphere. These get dissolved in rain water and come down as acid rain. 

Rain with a pH less than 5.6 is known as acid rain. Acid rain is caused by burning fossil fuels (especially coal) and by fertilizers used in intensive agriculture. These activities emit sulfur and nitrogen in gas compounds that are converted to sulfur oxides and nitrogen oxides. These in turn create sulfuric acid and nitric acid in rain. Acid rain may also be created from gases emitted by volcanoes and other natural sources. Acid rain harms fish and trees and triggers the release of metal ions from minerals into water that can harm people. The problem of acid rain in the United States has been addressed in recent decades by the use of scrubbers in coal burning power plants and catalytic converters in vehicles. 

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