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EWRS Herbicide‐Soil Working Group: Collaborative experiment on simazine persistence in soil
Author(s) -
WALKER A.,
HANCE R. J.,
ALLEN J. G.,
BRIGGS G. G.,
CHEN YUHLIN,
GAYNOR J. D.,
HOGUE E. J.,
MALQUORI A.,
MOODY K.,
MOYER J. R.,
PESTEMER W.,
RAHMAN A.,
SMITH A. E.,
STREIBIG J. C.,
TORSTENSSON N. T. L.,
WIDYANTO L. S.,
ZANDVOORT R.
Publication year - 1983
Publication title -
weed research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.693
H-Index - 74
eISSN - 1365-3180
pISSN - 0043-1737
DOI - 10.1111/j.1365-3180.1983.tb00561.x
Subject(s) - simazine , soil water , persistence (discontinuity) , environmental science , water content , soil science , environmental chemistry , chemistry , moisture , agronomy , pesticide , atrazine , biology , geology , geotechnical engineering , organic chemistry
Summary The effects of soil temperature and soil moisture content on the rate of simazine degradation were measured in the laboratory in soils from sixteen sites located in several different countries. First‐order half‐lives under standard incubation conditions were significantly correlated with clay content, organic carbon content and soil pH in a multiple linear regression. The temperature dependence of degradation was similar in the different soils whereas the moisture dependence showed considerable variation between soils. Persistence of simazine was also measured in the same soils in the field and at live additional sites. Weather records from the different sites for the periods of the Held experiments were used in conjunction with constants derived from the laboratory data in a computer program to simulate persistence in the field. In general, the model overestimated residues in the field. About half of the calculated residues were within 25% of those observed, an accuracy sufficient for practical purposes, but on several occasions the discrepancies between calculated and observed residues were greater than 50%. Possible reasons for the discrepancies and requirements for further experiments are discussed.