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Microbiological Studies on Urea‐Formaldehyde Preparations
Author(s) -
Fuller W. H.,
Clark K. G.
Publication year - 1948
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj1948.036159950012000c0046x
Subject(s) - chemist , citation , library science , citation database , chemistry , political science , computer science , law , organic chemistry , medline , scopus
U products appear to have definite possibilities as sources of slowly available nitrogen for fertilizer use (i, 5). The most promising products are formed by the reaction of urea and formaldehyde under such conditions and in such proportions that the final urea-formaldehyde mol ratio lies between 1.2 and 1.4. Such products contain between 36 and 38% nitrogen, are slightly soluble in cold water, and possess desirable physical properties. Small changes in the mol ratio of urea to formaldehyde have been shown by Yee and Love (5) to be accompanied by rather large changes in solubility and rate of nitrogen liberation. These compounds nitrify slowly at rates roughly proportional to their mol ratio and solubility index. The influence of the soil flora on the extent and rate of liberation of available nitrogen from ureaform is not known since the importance of these products for nitrogen fertilizing purposes only recently has been recognized. Although nitrification in soil is strictly a biological process, ammonification of some organic substances such as urea may be brought about by chemical as well as biological means. Whether or not ammonia may be liberated by chemical hydrolysis of urea-form products in soil media independent of microbial action remains to be determined. The purpose of the investigations reported here was to determine to what extent soil microorganisms influence the rate of release of available nitrogen from urea-form preparations.