# Assessment and Spatial Modelling of Agrochernozem Properties for Reclamation Measurements
## 3 Results
The water capacity in the plowable layer was equal to 43.0% (field moisture capacity), 45.0% (capillary moisture capacity) and 53.7% (total moisture capacity). With depth, these values decreased to 23.9, 25.9 and 29.3% in the Cca horizon, respectively. The wilting point of the A\({}_{1}\) humus-accumulative horizon was 14.2-14.3% and decreased to 11.8% with depth. The content of silt (56.2-65.9%) was dominant in the composition of all soil horizons; then, clay and sand contents were descending (21.4-28.9 and 7.8-14.9, respectively). Figure 2 shows water infiltration of the agrochernozem. Determining water infiltration showed that the average speed of water absorption from the soil surface was 1.52 mm/min and from a depth of 50 cm--2.41 mm/min, which, according to the classification of [PERSON] [37], belongs to the medium and high categories of water infiltration, respectively. Land irrigation increases the likelihood of contamination of soils and agricultural products by various pollutants, including heavy metals [53; 54]. Toxicants may also become more mobile in the soil profile [55]. The analysis of micronutrients and heavy metals showed low and medium cobalt, zinc and copper contents (Table 5). The average values of the heavy metals and micronutrient contents were 2.71 mg/kg for Pb, 0.18 mg/kg for Cd, 0.024 mg/kg for Hg, 0.13 mg/kg for Co, 0.33 mg/kg for Zn, 0.11 mg/kg for Cu and 11.27 mg/kg for Mn at the Aplow layer. The Pb, Cd and Hg contents were well below the maximum allowable concentrations. It can be assumed that if there were no  
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \begin{tabular}{c} **Horizon** \\ **(Depth, cm)** \\ \end{tabular}  & \begin{tabular}{c} **Bulk** \\ **Density,** \\ **g/cm\({}^{3}\)** \\ \end{tabular}  & \begin{tabular}{c} **Hardness,** \\ **kg/cm\({}^{3}\)** \\ \end{tabular}  & \begin{tabular}{c} **Porosity** \\ **Point,** \% \\ **R**/**cm\({}^{3}\)** \\ \end{tabular}  & \begin{tabular}{c} **Bilting** \\ **Point,** \% \\ **Point,** \% \\ \end{tabular}  & \begin{tabular}{c} **Field** \\ **Moisture** \\ **Capacity** \\ \end{tabular}  & \begin{tabular}{c} **Capillary** \\ **Moisture** \\ **Capacity** \\ \end{tabular}  & \begin{tabular}{c} **Total** \\ **Moisture** \\ **Capacity** \\ \end{tabular}  & \begin{tabular}{c} **Sand** \\ **(1–0.05 mm)** \\ \end{tabular}  & \begin{tabular}{c} **Silt** \\ **(0.05–0.001 mm)** \\ \end{tabular}  & \begin{tabular}{c} **Clay** \\ **(+0.001 mm)** \\ \end{tabular}  \\ \hline \ \begin{tabular}{c} Aplow \\ 0-28 \\ \(A_{1}\) \\ 84-125 \\ 125-150 \\ Cca \\ 150-180 \\ \end{tabular}  &
\begin{tabular}{c} 1.02 \(\pm\) 0.02 \\ 1.04 \(\pm\) 0.03 \\ 1.04 \(\pm\) 0.03 \\ 1.02 \(\pm\) 0.01 \\ 1.04 \(\pm\) 0.  
pollutants in the water used for irrigation, there will be no risk of contamination from agricultural produce. The effectiveness of soil element prediction models using the RF approach according to the error metrics (ME and RMSE) is presented in Table 6. As an indicator of site fertility, the SOC prediction model showed the RMSE value of 0.60, comparable to that of other authors [56; 57]. The RMSE values for pH, Mg, Ca, N, P and K were 0.48, 1.56, 2.51, 2.92, 1.57 and 4.57, respectively. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Soil Parameter** & **ME** & **RMSE** & **Top 3 Important Variables** \\ \hline SOC & 0.36\% & 0.60\% & B12, NDVI, Aspect \\ pH & 0.23 & 0.48 & Slope, Aspect, Elevation \\ Mg & 2.43 cmol(+)/kg & 1.56 cmol(+)/kg & Slope, MRVBF, B2 \\ Ca & 1.58 cmol(+)/kg & 2.51 cmol(+)/kg & B11, B4, MRVBF \\ N & 8.53 mg/kg & 2.92 mg/kg & NDVI, B2, Aspect \\ P & 2.47 mg/kg & 1.57 mg/kg & B12, B8A, Elevation \\ K & 20.88 mg/kg & 4.57 mg/kg & B8A, Aspect, B11 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Test performance of the RF for soil properties at 0–10 cm depth. Figure 2: Water infiltration of the agrochernozem studied: (**a**) water absorption speed from the soil surface; (**b**) water absorption speed from a depth of 50 cm. The top three important variables for each soil feature were different.