Spatial variability of saturated hydraulic conductivity and its links with other soil properties at the regional scale

Abstract Saturated hydraulic conductivity (K) is a key property for evaluating soil water movement and quality. Most studies on spatial variability of K have been performed at field or smaller scale. Therefore, the aim this work was to assess (quantify) distribution larger regional scale in south-eastern Poland its relationship with other properties, including intrinsic sand, silt, clay contents, relatively stable organic carbon, cation exchange capacity (CEC) temporally variable content (WC), total porosity (FI), dry bulk density (BD) surface layer (0–20 cm). The relationships were assessed using semivariogram cross-semivariogram. studied region (140 km 2 ) predominantly permeable sandy soils low fertility productivity located part (Podlasie region). mean sand carbon contents are 74 0.86 their ranges (in %) 45–95 0.002–3.75, respectively. number individual samples varied from 216 228 (for K, WC, BD, FI) 691 properties. best fitting models adjusted empirical (exponential) cross-semivariogram (exponential, Gaussian, linear) used draw maps kriging. results showed that, among properties studied, most (coefficient variation 77.3%) significantly ( p < 0.05) positively correlated (r = 0.300) negatively – 0.283). normal close obtained by natural logarithmic root square transformations. 2.597 m day −1 ranged 0.01 up 11.54 . autocorrelation (range) single (direct) semivariograms 0.081° (8.1 km), while it favourably increased 0.149°–0.81° (14.9–81 km) cross-semivariograms OC textural fractions, CEC as auxiliary variables. generated allowed outlining two sub-areas high above 3.0 northern sandier (sand > 74%) less silty (silt 22%) and, lower southern study region. Generally, values depended share fractions. On hand, between much (from ~ 15 81 than (0.3–0.9 km). This knowledge supportive making decisions related land management aimed alteration improve resources crop reduce chemical leaching.