Abstract

In this study, geostatistical analysis of electrical conductivity (EC) and soil pH values, soil clay (C), silt (Si), and sand (S) content, permanent wilting point (PWP), organic matter (OM), field capacity (FC) and water stable aggregates (WSA) were investigated in 1500 ha degraded grassland of Kayseri, Turkey. Coefficients of variations (CVs) of EC (125 -103 dS m^-1) were higher than the other soil properties while the lowest CV was found for pH (5 - 5) in 0 - 30 (D1) and 30 - 60 cm (D2) depths.  To summarize the relationships among examined soil properties, Pearson Correlation analysis was performed and significant correlations were found between LnEC-LnpH and selected physical soil properties for D1 and D2 (p<0.01 and p<0.05). Independent sample t-test indicated that the means of EC and organic matter content of soil (OM) were statistically different while there were no differences for the others (p<0.05). In geostatistical analysis, exponential model was fitted to experimental variograms for LnEC, LnC, SqSi, and LnS of D1 and LnEC of D2, while spherical model was used for LnpH, SqOM, PWP, SqFC, and SqWSA of D1 and LnpH, LnC, SqSi, LnS, SqOM, PWP, FC, and SqWSA of D2. Selected soil variables showed different degree of spatial correlation. Kriging maps showed environmentally risky areas of the study site.

Key words: Salinity, alkalinity, geostatistics, spatial variation, kriging.