With a well-prepared sampling plan, we obtained additional information on the heterogeneity of soil bulk density on arable land. We selected eight fields in the Celje area, where at least 1 month has passed since the last tillage. The soil type is stagnosol, on one field partially gleysol. All soil samples in one year were taken on the same day, and we assumed that the soil was exposed to the same amount of precipitation. Therefore, we assumed that the variability of the measurements depended on the heterogeneity of the soil and the method of sampling. After one year, we repeated the sampling on a smaller scale and compared soil bulk density and gravimetric water content in the soil between years. We found that the average bulk density on the field ranged from 0.80 g/cm3 to 0.98 g/cm3 in 2020 and from 0.97 g/cm3 to 1.11 g/cm3 in 2021. The coefficients of variation for soil bulk density ranged from 0.8 % to 10.2 % in 2020 and in a smaller range from 3.5 % to 6.0 % in 2021. The coefficients of variation for gravimetric water content were higher in 2020, ranging from 11.9 % to 20.4 %, and in 2021, ranging from 5.9 % to 10.5 %, with a higher average gravimetric water content in 2021.
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