Seasonal abundance of soil mites (Acari) in experimental agroecosystems: Effects of drought in no-tillage and conventional tillage

Soil mite abundance were measured during a 2-year period (1984–1986) in experimental agroecosystems subjected to conventional tillage or no-tillage treatments. The experimental site is a humid, subtropical floodplain located in Clarke County, GA, U.S.A. Soil mite abundances were greater in conventional tillage during 1984–1985, but became greater in no-tillage during 1985–1986. Soil mite build-up in no-tillage coincided with a major drought during the summer of 1986, when both Prostigmata and Oribatei showed large increases in numbers. Although the effects of drought conditions cannot be readily separated from other trends (since droughts are unreplicated and lack controls), higher populations under no-tillage conditions are consistent with the water retention properties of conservation tillage agroecosystems.