The effect of soil management on the soil faunal makeup of a cropped andosol in Central Japan

The effects of four contrasting soil-management practices on soil fauna in an andosol cropped to upland rice and winter wheat, were examined after a 3-year period. The treatments were as follows: direct drilling with organic mulch and without fertilizer: direct drilling without mulch and fertilizer: rotary digging without mulch and with fertilizer: direct drilling without mulch and with fertilizer. The density of 5 animal groups, namely Enchytraeidae, Oribatei, Acari except Oribatei, Collembola and macro-animals, was significantly lower in the direct drilling without mulch and the rotary digging, compared to the other treatments. In comparison with rotary digging, direct drilling with fertilizer, increased soil hardness and enchytraeids and macro-animal densities, but decreased the yield of upland rice. The organic mulch of decomposed plant materials increased the density of all 5 animal groups. The organic mulch also increased soil pH, water content and ignition loss of soil, and decreased soil hardness.