Small-scale spatial variability of selected soil properties in a sloped cultivation area  A case study of Phetchabun province's highland region, Thailand

Main Article Content

Wongkaew, A.
Saito, H.
Chueasamat, A.
Aramrak, S.
Nakasathien, S.
Sreewongchai, T.

Abstract

Spatial variability analysis revealed distinct patterns among selected soil properties in a small-scale sloped cultivation area in the highland region of Phetchabun Province, Thailand. Descriptive statistics revealed low coefficients of variation (CV) for soil bulk density (BD), gravimetric soil water content (GWC), soil pH, soil organic carbon (SOC), and soil organic matter (SOM), indicating little variability. Exchangeable potassium (Kexch), exchangeable calcium (Caexch), and exchangeable magnesium (Mgexch) showed moderate variability, while both saturated soil hydraulic conductivity (Ksat) and available phosphorus (Pavai) displayed high variability. A geostatistical analysis, where residuals are kriged before adding with trend obtained through linear regression, reliably predicted BD, GWC, and Kexch under a small sample size; however, caution is needed for soil pH predictions. The study underscored the impact of a small sample size on log-transformed Ksat, SOC, SOM, log-transformed Pavai, Caexch, and Mgexch correlations. Overall, the findings are emphasized the importance of spatial variability analysis in guiding precise agricultural practices and resource utilization for small-scale sloped cultivation areas.

Article Details

How to Cite
Wongkaew, A., Saito, H., Chueasamat, A., Aramrak, S., Nakasathien, S., & Sreewongchai, T. (2026). Small-scale spatial variability of selected soil properties in a sloped cultivation area  A case study of Phetchabun province’s highland region, Thailand. International Journal of Agricultural Technology, 22(2), 1017–1044. https://doi.org/10.63369/ijat.2026.22.2.1017-1044
Section
Original Study

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