The experiment was conducted from 1983 to 1987. Under reducedtillage and located area-broadcast sowing, paddy fields avoid much soil destruc-tion caused by conventional tillage. This tillage and planting method makes thetillage layers form an 'sticky upper and loose lower' soil structure. As a resultventilation is improved; good conditions for the growth of rice crops and the ac-tivities of micro-organisms are created; the quantity of microorganisms is increas-ed tremendously and their oxidizing metabolism is virtually intensified; theactivities of soil enzymes and microbial respiration are al...
