Document


Title

Contribution of some soil fungi to natural and heat-induced water repellency in sand
Document Type: Journal Article
Author(s): S. M. Savage; James P. Martin; J. Letey
Publication Year: 1969

Cataloging Information

Keyword(s):
  • fungi
  • heat
  • heat effects
  • Penicillium
  • soil management
  • soil temperature
  • soils
  • temperature
  • water
  • water repellent soils
Record Maintained By:
Record Last Modified: June 1, 2018
FRAMES Record Number: 38566
Tall Timbers Record Number: 13172
TTRS Location Status: In-file
TTRS Call Number: Fire File DDW
TTRS Abstract Status: Okay, Fair use, Reproduced by permission

This bibliographic record was either created or modified by the Tall Timbers Research Station and Land Conservancy and is provided without charge to promote research and education in Fire Ecology. The E.V. Komarek Fire Ecology Database is the intellectual property of the Tall Timbers Research Station and Land Conservancy.

Description

Eight species of fungi isolated from a water repellent soil were incubated for varying periods of time in silica sand. In their latter stages of growth. two of the fungi, Aspergillus Sidowi and Penicillium nigricans, caused limited water repellency in the sand. All the fungal sand cultures exhibited water repellency when heated briefly at temperatures between 200C and 400C. The times required to produce and destroy water repellency in the sand cultures at the various temperatures were similar to those required by the natural soil from which the fungi were isolated. The fungal sand cultures and natural water repellent soils were extracted with either water, methanol, acetone, or ethyl ether. The methanol and water extractions destroyed the natural water repellency of the A.sidowi and P. nigricans cultures. Methanol and water extractions also destroyed the water repellency of the heated sand cultures if the extractions were made before the heat treatments; however, if the extractions were made after the sand cultures had been heated, the water repellency of the samples was not affected. Wettable silica sand treated with the methanol extracts of the sand cultures exhibited water repellency when heated. Both the heat-induced and natural water repellency of the soil was not affected by any of the solvent extractions, but wettable sand treated with each of the extracts was made water repellent by heat. A variety of known organic substances was applied to wettable silica sand and the water repellency of the treated sand determined before and after heating. Amines were the only class of substances tested that caused water repellency in sand before heating. A variety of substances, however, caused heat-induced water repellency in the sand. The heating conditions required to cause water repellency were similar to those required by fungal sand cultures and natural water repellent soil. The primary conclusion of the study was that heat-induced water repellency may be a universal property of soils rather than property specific to a limited number soils.

Citation:
Savage, S. M., J. P. Martin, and J. Letey. 1969. Contribution of some soil fungi to natural and heat-induced water repellency in sand. Soil Science Society of America Proceedings, v. 33, p. 405-409.