Justification of the approach to establishing levels of soil fertility (on the example of a farm)

The information of agrochemical monitoring of elementary sections of fields allows us to study soil fertility in more detail. For example, using cluster and discriminant analysis methods to identify different levels of agricultural soil fertility. At the same time, it is necessary to comply with the criteria of grouping by fertility. 1. Low spatial contrast of agrochemical properties. If it is present (checked by indicators of asymmetry and kurtosis), then it must be weakened - to bring the data values in the sample to a normal distribution or close to it. Otherwise, information on some indicators may be veiled by extremely high values of others. 2. Reliable participation of all registered soil indicators in the allocation of several groups of sites with similar characteristics (cluster analysis). 3. Equivalent (according to Lambda-Wilkes) and reliable contribution (in terms of significance) of indicators in the allocation of fertility levels. At the same time, it is possible to determine the proportion of sites with different classes of availability of batteries or degrees of acidity. The research was carried out on the basis of data from agrochemical monitoring of soil indicators of leached chernozem of heavy loamy granulometric composition in JSC "General Skobelev", Ryazan region. Salt acidity, mobile forms of phosphorus and potassium, humus were determined by publicly available methods. Two fertility options have been established - conditionally level No. 1 and No.2. According to level 2, the acidity of leached chernozem is shifted to a greater extent to a slightly acidic region compared to level No. 1. The ranges of values for mobile phosphorus correspond to the average - 72-92 mg/kg (level No. 1) and elevated - 103-122 mg/kg (level No. 2) security classes, for mobile potassium - an elevated class. However, for level No. 2, the values were higher (145-167 mg/kg) compared to level No. 1 (114-138 mg/kg). A similar nature of differences was observed in humus. We believe that the information on the fertility of leached chernozem, characteristic of level No. 1, can serve as a guide for the soil of elementary areas with the worst characteristics.

fertility levels, exchange acidity, mobile potassium, mobile phosphorus, humus, cluster analysis, discriminant analysis, leached chernozem