Aplica？？o superficial de calcário no sistema plantio direto consolidado em solo arenoso

surface liming is an alternative way to correct soil acidity. the objective of this study was to evaluate the effects of surface liming on soil properties and crop yield under no-tillage. the experiment was carried out at federal university of santa maria, southern brazil, on a typic hapludult, under no-tillage, for five years, with ph 5.0, 13, 140 and 610g kg-1 om, clay and sand, respectively. the lime rates used were 0, 1.2, 1.8 and 3.6mg ha-1, applied on the soil surface without incorporation. the crops used were corn (94/95), black oat (95 and 96) and soybean (95/96 and 96/97). grain yield was evaluated for corn and soybeans; dry matter production was evaluated for black oats. six, 12, and 18 moths after liming, soil was sampled at four depths, 0-2.5, 2.5-5, 5-10 and 10-15cm to measure some attributes related to soil acidity. treatments were set up in a complete block design with four replications. superficial applied lime did not induce crop yield differences, but modified acidity and increased ph, calcium and magnesium contents in the 0-5cm layer.