Litter Fragmentation By Isopods as Affected By Herbicide Application

Abstract

Litter fragmentation, an essential precursor of nutrient cycling, as affected by herbicides has been studied by sampling black cherry (Prunus serotina, Ehrh.) and birch (Betula verrucosa L.) leaves and litter at different intervals after treatment with herbicides (2,4,5-T, amitrole or glyphosate) and offering these batchwise or continuously to isopods (Philoscia muscorum Scopoli) in the laboratory. Herbicides have an intended impact on plant biochemistry and change the physico-chemical composition of the leaves. Isopods become affected by direct contact, by direct intake of the herbicide accumulated in the litter and by a reduced consumption rate due to the herbicide. Depending on the specific combination of litter and herbicide this can promote fragmentation or it can seriously hamper litter fragmentation. Therefore litter fragmentation should become part of a procedure to assess the ecotoxicological impact of soil contaminants on soil fauna.