Ecology-energy efficiency of tehnology growing agricultural crops in South steppe conditions

Abstract

During 2011–2013 years in a stationary field experiment on southern chornozem of Askaniya State Agricultural Experimental Station (Institute of irrigated agriculture of the National Academy of Agrarian Sciences of Ukraine (the Kahovka regions of Kherson Oblast) a comparative analysis of changes in the energy capacity of the soil in relation to anthropogenic energy costs of different technologies growing crops was made. Calculations on four fields, each of which is treated by the three different technologies or soil processing: a) traditional (with turning of layer of the soil on crops of peas and sorghum and processing without soil layer turn in versions with mustard and wheat’s), b) minimum processing of the soil (surface tillage or «mini-till») and no-till (or so-called «direct sowing») were carried out. A research was conducted in four field crop rotation: winter (spring-sown) wheat, sorghum, mustard. There was a positive energy balance for all technologies growing crops (when it was saved up by the energy soil more than it is lost) on fields № 1 and № 3, and negative on fields № 2 and № 4. In the case of a positive balance, the amount of stored energy in the soil under different technologies varies 6,5–18,9 GJ/ha. By negative balance energy losses are ground 21,7–37,2 GJ/ha. The use of no-till technology reduces soil energy capacity in comparison by traditional soil processing on 3,36 GJ, which is associated with a significant reduction in crop yields and reduction of organic matter coming from plant remains it was established. The coefficient of energy efficiency technologies (ratio of energy capacity crop to the total harvest human energy is spent in agricultural landscapes in growing each crops) for all years of observation has a positive value (field № 1 and № 3), and negative (field № 2 and № 4). In the first case, its value is 0,13–0,51, the second –0,69–0,44. The highest rate was observed in the traditional technology growing crops, the lowest – for no-tiil technology. The total change in the energy capacity of the soil under the different agricultural technologies for all years of observations shows that the least environmental and energy efficiency in all cultures showed no-till. Based on the above data, it can be argued that the properties of no-till technology which declared (reducing losses from soil erosion, improve physical and chemical properties of the soil, etc.) do not provide any benefits to which the energy balance of the soil, and, moreover, adversely affecting its energy potential. Direct seeding also has a lower environmental and energy efficiency compared to conventional and minimum tillage technology. All this is due to a decrease in productivity, leading to a decrease in soil joining the main source of energy soil – plant residues. Between ecology-energy and energy valuation of technologies growing crops on all versions of research there is a direct correlation – the higher the energy efficiency of technologies growing crops the better its ecology-energy indicators, due to the size of the annual energy investments, which are proportional values of vegetable remains. In turn vegetable remains depend on crop yields and energy density of anthropogenic origin.