Vertical distribution of soil mites (Acari) in conventional and no-tillage agricultural systems

Summary Soil mite abundance was measured at four depths (0–5, 6.5–11.5, 13–18, and 19.5–24.5 cm) in agricultural plots under no-tillage or conventional tillage in Clarke County, Georgia, USA. The vertical distribution of mites was not significantly different between the two tillage systems: Most mites were found in the top 0–5 cm zone. This was the zone where greater moisture content occurred, and (in other studies) was the zone of maximum root biomass and microbial activity. Among mite suborders, only the Prostigmata were found in any abundance below 5 cm. Mite populations declined dramatically on occasions when the soil moisture exceeded field capacity, but did not appear to migrate vertically.Dedicated to the late Prof. Dr. W. Kühnelt