Features of the investigation of agrophysical properties of blackship by different treatment systems

Abstract

The study of soil physical properties is a theoretical and practical basis for choosing of a cultivation system. It is an important agri-acceptance of modern agriculture. In the scientific literature, many publications in periodicals is devoted to the study of soil physical properties. In this paper are shown features of study of physical parameters of soils on southern chernozem, which characterized by low-humus content under different cultivation systems for corn: plowing, chisel, No-till and grassland are highlighted. The methodological features of the research are described in detail in the paper. Determination of physical parameters for different soil tillage systems showed that the five-year application of No-till for maize significantly improved compared with the plowing, the structural composition of the southern chernozem was 62.4–66.6%, and the aggregates had a rounded form with pronounced porosity. Soil density was also optimal within the range of 1.10– 1.26 g/cm3, which gives grounds for positively assessing the investigated agriculture measure and the possibility of its introduction into production. Key words: physical soil properties, southern chernozem, No-till, plowing, bulk density, soil structure, soil hardness.
 
Topicality. For the southern regions of Ukraine, due to the dry conditions of the climate and for the purpose of moisture accumulation, actual research is being carried out on the No-till of the soil, which prevents it from excessive water evaporation at the expense of the mulch and protects against wind erosion. At the same time, it is important to study the agrophysical properties of soils, as the theoretical and practical basis for the introduction of different cultivation systems. The purpose of the research was to study the effect of No-till cultivation on the agrophysical parameters of the southern chernozem with low-humus content and heavy-gravel texture, in comparison with traditional plowing, chisel loosening and grassland.
Materials and methods of research. Studies of physical properties of soils have their own specifics, since their parameters are sufficiently variable in area, especially in cultivated soils, as well as dynamic during the growing season. The determination of agro-physical parameters was carried out on the experiments of the southern branch of the research and production enterprise "Rise-Agro" located in the village Tavria of the Tokmak district of Zaporizhzhia region, in different variants (field plowing, chisel and No-till cultivation) at the end of the vegetation of maize and on the turnip, near field experiments. The specificity of agrophysical studies was that in a section width of 200 cm across the crop, the soil hardness was determined by using the Reawaken device from soil surface in fourfold repetition every 30 cm long, and then, at the place of the plunger plugs, the gauge made a trap with a depth of 50, width 40 and 200 cm long. In this trap, also, every 30 cm of length, the bulk density of soil was determined by the cutting ring method according to Kachynskiy in soil layers at 0-10, 10-20, 2030, 30-40 cm. Soil samples for structure determining were also selected in a six-fold repetition layer by Savinov method. Water permeability from the soil surface was determined by the method of pouring squares. Research results and their discussion. Regarding the structural and aggregate composition of chernozem of the south for different cultivating systems, we note the following. In the plots and chisel cultivars, the increased content of briils is noted - 43,6-44,0% and 27,9-47,4% respectively, which gives us the basis to state the compression (densified) type of structure with low porosity, which is due to the effect of heavy agricultural technology. The content of air-dry aggregates in the size of 10-0.25 mm for plowing was 55.4-56.6%, which is estimated as the average level of degradation. The five-year application of No-tillage treatment resulted in improved structural and aggregate composition in all studied layers of soil. The content of valuable air-dry aggregates in this variant was depending on the layer in the range of 62.4-66.6%, which corresponds to a weak level of degradation. It is also necessary to note the predominantly rounded form of aggregates with pronounced intra
aggregate pores. At the turn of the grassland we note the best structural and aggregate composition of the soil, the content of valuable aggregates after the dry scattering was within 68,4-84,1%. In the variant with No-till treatment there is a tendency to dissolve the upper layers (0-10 and 10-20 cm) of soil to 1,10-1,22 g / cm3, compared to the plowing of 1,21-1,28 g / cm3, which is due to considerably less machine load on the soil and a more pronounced granular structure. Also, the spatial variation in the density of the gravel for No-till cultivation decreases and, to some extent, the anisotropy of the soil with depth is leveled. The analysis of the correlation between bulk density and hardness showed a positive correlation with a coefficient of 0.61. An increase in moisture reduced the density of soil formation, the tightness of the connection -0.56. According to literary sources, the range of allowable compaction density for normal growth of field crops in heavy-soil soils is within the range of 1.15-1.40 g / cm3, and for corn growing – within 1.05-1.30 g / cm3 of the average value is 1.19 g / cm3. In general, in our detailed studies, the bulk density of the southern chernozem for different cultivating systems was, basically, in optimal parameters in the 0-40 cm layer. Although in the variant with a plow in a certain part in a layer of 10-20 cm there was a seal, which was 1.30-1.33 g/cm3. In the case of chisel cultivation, the rebonding also appeared in a certain part of the layers of 10-40 cm in the range of 1.31-1.41 g/cm3. Conclusions. 1. System study of agrophysical properties of soils provides the basis for more detailed research and evaluation of the impact of different systems of cultivation on their fertility and to substantiate the agroeconomic efficiency in modern agriculture. 2. Five-year application of No-till cultivation for corn resulted in the formation of optimal agrophysical parameters of southern chernozem. The content of agronomic-valuable aggregates was 62.4-66.6%, while the aggregates had a rounded form with pronounced porosity. The bulk density was also optimal within
the range of 1.10-1.26 g/cm3, which gives grounds for positively assessing the investigated agro-plant and the possibility of its introduction into production.