INTERACTIONS BETWEEN BIOTIC COMPONENTS IN SOILS AND THEIR MODIFICATION BY MANAGEMENT PRACTICES IN CANADA: A REVIEW

Abstract

Soil microfloral and faunal components are vitally concerned with soil fertility, plant growth, and decomposition of plant residues and pesticides and are interrelated in a complex manner. Interactions occurring between dominant soil biotic components have been compiled and each interaction rated according to its importance in the literature. This review is intended as a framework on which further information can be superimposed and the relative importance of interactions revised. The general format used is as follows: functions of major biotic components; their interactions; the effects of management practices, excluding pesticides, on the components; and the effects of pesticides. A concluding section suggests where further research is needed. In particular, information is required on the effects of Collembola, mites, enchytraeid worms, and protozoa on actinomycetes; of discing and severe winter conditions on faunal and microfloral populations; of seed treatment fungicides on soil fauna; of lindane, dasanit, furadan, and lannate insecticides on fungi, bacteria, and actinomycetes; of lindane and diazinon on nematodes, and of dasanit, furadan, and lannate on earthworms, enchytraeid worms, Collembola, and mites. Also, more information is needed on the effects of barban, diallate, and triallate herbicides on the major soil biota and of MCPA on the soil fauna.