Energy aspects of alfalfa seed production in southern Ukraine

Abstract

This paper presents the findings of the study on determining the energy efficiency of alfalfa seed production in the first year of life in the south of Ukraine using various technologies, which is relevant for their adequate assessment in conditions of energy conservation of non-renewable resources. The purpose of the study was to determine the most energy-efficient technology for growing alfalfa varieties for seeds. Methods of observation, comparison, and field experiment were used. The study investigated the varieties Nadezhda, Veselka, and Unitro for cultivation using conventional technology (without manual and chemical weeding), which included manual weeding without herbicides and a chemical method to reduce crop contamination. It is established that the production of alfalfa seeds requires a significant expenditure of energy-intensive non-renewable resources for the reliable protection of crops from weeds. It was found that the energy intensity of the technology with chemical weeding of alfalfa crops in the first year of life increased by 32.1-32.4% compared to the control (without weed destruction). Energy consumption reached 13,706 MJ/ha (Nadezhda grade, yield 1.46 centner/ha) against 10374 MJ/ha (yield 0.43 centner/ha) in the control. At the same time, due to the introduction of herbicides, 2.6 times less energy was consumed per 1 centner of seeds (9,388 MJ) compared to the control (24,126 MJ). The energy efficiency coefficient (Kee) for chemical weeding of crops increases from 1.28 to 2.99 (Nadezhda variety) and from 1.35 to 3.13 (Unitro variety). Labour costs are reduced by 2.9 or more times due to chemical weeding of crops. Thus, in the control areas, 25.3 (Nadezhda variety) — 23.3 person-hours were consumed per 1 centner of seeds (Unitro variety), and with the introduction of herbicides, this indicator decreases to 8.8, 8.4 person-hours, respectively. The practical significance of the study lies in the proposal of an energy-saving technology for growing alfalfa for seeds.