HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Wang, C. H. Articles by Broadbent, F. E. Search for Related Content PubMed Articles by Wang, C. H. Articles by Broadbent, F. E. Agricola Articles by Wang, C. H. Articles by Broadbent, F. E.

Kinetics of Losses of PCNB and DCNA in Three California Soils¹

ABSTRACT

The losses of two fungicides, PCNB (pentachloronitrobenzene) and DCNA (2,6-dichloro-4-nitroaniline) in three California soils differing in their properties were measured in laboratory experiments. Under controlled temperature and moisture content, both fungicides were lost according to first-order kinetics. The calculated half-time (t) was employed to indicate the stability or the persistence of the fungicides. The half-times of PCNB were found to be 4.7, 7.6, and 9.7 months for Columbia fine sandy loam, Sacramento clay, and Staten peaty muck, respectively, while those of DCNA were 30, 16.2, and 13.6 months, respectively. Thus higher soil organic matter was associated with slower PCNB loss but enhanced DCNA loss. It was also found that clay affected losses of the fungicides in a similar way. Evidence was obtained to show that PCNB was lost mainly through volatilization whereas DCNA was lost through microbial degradation and other processes.

¹ Contribution from the Dep. of Soils and Plant Nutrition, Univ. of California, Davis. 95616.

² Former Research Assistant and Professor of Soil Microbiology, respectively.

Received for publication March 23, 1972. Accepted for publication May 16, 1972.