SOIL MESOFAUNAL STUDIES UNDER DIFFERENT VEGETATIVE REGIMES IN NORTH CENTRAL ALBERTA

Research on soil mesofauna distribution and diversity was conducted on a cultivated Gray Luvisol near Breton, Alberta. Particular reference was made to the soil Collembola (springtails) and the Acarina (mites). Seven different vegetative regimes (grass litter, balsam leaves, aspen leaves, straw litter, fescue grass, alfalfa, check) were established on 14 (2 m × 2 m) microplots. Microarthropod distribution and diversity were found to be dependent on a number of soil parameters such as temperature, moisture, depth, nutrient status, microhabitat availability and vegetative cover. Seasonal changes were also monitored. Examination of soil thin-sections revealed that a wide variety of fauna contribute to the reorganization of fabrics, especially in the upper 7 cm of soil. These fauna varied in their significance throughout the microplots. Fecal pellets of 280–350 μm size were encountered, commonly comprising mull-like material. Insect larvae are thought to be responsible but their type is unknown. The authors stress the need for further research in this area to establish the role and importance of the soil mesofauna in the soil ecosystem. Key words: Soil mesofauna, Acarina, Collembola, soil microstructure