Spatial varibility of soil physico-hydrical properties is related to soil genesis and management, and affect crop production. The objectives of this study were to identify and to relate spatial variability of saturated hydraulic condutivity (K(qs)), soil mechanical resistance (R), soil texture, and A horizont depth, of a Typic Hapludalf under no-till, with wheat yield and hectoliter weight. This experiment was conducted in the winter of 1999, on a 1.51 ha no-till wheat field. Soil and plant characterization was done on five transects with 100m in the East-West direction, with sampling points 10m apart. Values of R for the depths of 5cm, 7.5cm, 10cm and 15cm and A horizont depth showed normal distribution. Spherical model semivariograms were adjusted for K(qs), R in the 30cm depth, clay content, and A horizont depth. Exponential model for R in the 2.5cm and 5cm depths, clay and silt content, and wheat yield and hectoliter weight. For the 7.5cm, 10cm, 12.5cm, 15cm and 17.5cm depths, R semivariograms showed pure nugget effect; in these depths the machinery traffic and previous soil management effects are prominent. Wheat yield and hectoliter weight did not correlate with K(qs) and R. When evaluating the spatial variability in R for soil layers deeper than 5cm, the distance between samples points should be smaller than 10m.
geostatistics; soil mechanical resistance; saturated hydraulic conductivity
