International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

By assessing basic agro-technical factors, optimal decisions can be made for good agricultural practice on soils with heavy mechanical composition, such as the Haplic Vertisols.
The aim of the study is to identify the changes in the 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, a field trials, based on the block method in the Sofia Region on a Haplic Vertisols were carried out.
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.

Applying appropriate tillage systems, agro-technical and ameliorative measures can stop the negative changes in soil functions and stabilize and improve soil fertility through a systematic agro-technical approach.
The aim of the study is to investigate the effect of the introduction of new solutions in agro-technology on cultivation of arable crops on soils with impaired fertility. In a three-field crop rotation with potato, wheat and corn cultivation, after the application of soil tillage and liming systems, it has been found that soil tillage systems have a direct and indirect impact on the productivity of crops grown under crop rotation, setting the conditions for the cultivation of crops other agrotechnical activities.
The deeper basic cultivations applied to the potatoes on Chromic Luvisosl and EutricPlanosols, leads to lower values of bulk density and strength.
Potato cultivation has a significant effect on both limestone and ash input, with a positive effect on corn and wheat.
On the basis of the results obtained from the field experiments, a technology for the production of potatoes and wheat grown in a three-field crop rotation on soils with medium to highly acidic reaction of the soil solution – Chromic Luvisosl and EutricPlanosols in the study area is recommended.