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The Influence Of Antiseptics On The Bacterial And Protozoan Population Of Greenhouse Soils: Part I. Naphthalene.
Author(s) -
Jacobs Stanley Edward
Publication year - 1931
Publication title -
annals of applied biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.677
H-Index - 80
eISSN - 1744-7348
pISSN - 0003-4746
DOI - 10.1111/j.1744-7348.1931.tb02288.x
Subject(s) - naphthalene , bacteria , biology , population , microorganism , soil water , incubation , environmental chemistry , nitrifying bacteria , botany , agronomy , nitrogen , chemistry , ecology , nitrification , biochemistry , organic chemistry , genetics , demography , sociology
S ummary . 1. The effects of treating cucumber soil, previously air‐dried, with naphthalene, are as follows: (a) The number of bacteria immediately increases rapidly, but very soon decreases again, rapidly at hst, and then more slowly. (b) The development of protozoa is suppressed until most of the naphthalene has disappeared, after which rapid multiplication begins. (c) Ammonia (in an abnormally rich soil) first decreases in amount, and then accumulates to a considerably greater extent. 2. The increased bacterial population is composed partly of organisms which are using the naphthalene as a source of food, and partly of organisms which do not decompose naphthalene. 3. The history of the protozoa in the soil after the disappearance of the naphthalene is one of bursts of activity at irregular intervals. Each period of activity of the amoebae results in a decrease in the numbers of bacteria. The periods of activity of the flagellates are not closely related to fluctuations in the bacterial numbers. 4. The naphthalene‐decomposing bacteria utilise the supply of available nitrogen in the soil; as soon as the supply of naphthalene becomes exhausted, these bacteria attack the organic matter of the soil, resulting in an increase in the amount of ammonia in the particular soil under investigation. 5. The presence or absence of an initial lag in the naphthalene decomposition depends upon the temperature of incubation of the treated soil. 6. Strains of bacteria capable of using naphthalene as their sole source of carbon have been isolated. One of these strains has been shown to produce phthalic acid as an intermediate product in the decomposition of the naphthalene. 7. The reaction of the soil tends to become more alkaline after the disappearance of a quantity of naphthalene. Treatment with a second dose results in a temporary production of acid, which is probably carbonic acid.