Influence of Agro-Technical Treatments on Some Physical and Agrochemical Parameters of Haplic Vertisols

By assessing basic agro-technical factors, optimal decisions can be made for good agricultural practice on soils with heavy soil texture, such as the Haplic Vertisols. The aim of the study is to identify the changes in the physical and agrochemical status of Haplic Vertisols that occur under the influence of applied agro-technical measures. For the achievement of the purpose in the period 2016 -2019, field experiments, based on the block method in the Sofia Region on a Haplic Vertisols were carried out. The study found out that soil moisture was a major limiting factor for cropdevelopment. The soil moisture content is influenced by the type of soil tillage, although the density of the weeds is also less affected by the parameter. The bulk density of the Haplic Vertisols is inversely correlated with the soil moisture content. In the case of deep loosening of maize, its values are reduced compared to those with plowing. Lower values were found for the parameter after plowing as a pre-sowing treatment for wheat, compared to the variants with disking. The applied fertilization mainly affects the content of nitrate and ammonium nitrogen, the phosphorus forms remain with low values, it is clearly necessary to raise the norm and with a methodical approach it is necessary to achieve a sustainable level of absorbed phosphates. The content of the absorbed potassium is still satisfactory, and based on the data from the analysis, its reduction and export with the produced products are smaller.