SORPTION AND DEGRADATION OF ATRAZINE IN MIDDENS FORMED BY LUMBRICUS-TERRESTRIS

Little information is available about the fate of herbicides in midden s formed by Lumbricus terrestris. The midden and surrounding soil mate rials from no-till and conventionally tilled fields were measured for their ability to sorb and biodegrade atrazine [2-chloro-4-(ethylamino) -6-(isopropylamino)- s-triazine]. For samples from the conventional ti llage system, atrazine sorption was similar in middens and in the surr ounding soil, while under no-till atrazine sorption was higher in midd ens than in the surrounding soil. Atrazine degradation under no-till w as slower in the middens than in the surrounding soil, consistent with a commonly observed inverse relationship of sorption and degradation. Under conventional tillage, however, atrazine degradation was greater in the middens than in the surrounding soil, despite little differenc e in sorption between the two treatments. (C) 1997 Elsevier Science Lt d.