The influence of climatic changes on the formation of the productivity of corn crops for green fodder in the Central Forest- Steppe of Ukraine

Abstract

Purpose. The purpose of the study was to assess the possible impact of climate change on the formation of the productivity of corn crops on green mass in the conditions of the Central Forest Steppe of Ukraine. Methods. The work compares the forecasted data with the past, in particular, the average multi-year values for the base period. In this study, the period from 1991 to 2020 is taken as the base. To assess the impact of possible climate changes, the RCP 6.0 scenario (representative concentration trajectories), which is a stabilization scenario and is currently considered the most realistic option, and the RCP 6.0+СО2 scenario, which takes into account a 30% increase in CO2, were used. Results. As a result of the conducted research, it was established that the vegetation period of corn to obtain green mass under the conditions of climate change will be reduced by 11 days, which will lead to a reduction in the duration of interphase periods, especially the interphase period of panicle shedding – milk ripeness. At the same time, the average air temperature is expected to increase by 1°С on average during the period, and during the period of panicle shedding – milk ripeness by 2.5°С. An increase in the amount of precipitation compared to the basic conditions is expected only during the sowing-seedling period – up to 60%. In general, a 12% decrease in precipitation is expected during the growing season. According to the scenario data (RCP6.0), a 10% decrease in the value of the maximum leaf surface area is expected compared to the baseline data, as a result – a 16% decrease in yield. But due to an increase in CO2 by 30%, we can expect an increase in the value of the maximum leaf surface area by 6% compared to the baseline data, which can lead to a decrease in yield by only 4%. Findings. Based on the climate change scenario (during 2021–2050) and the dynamic model of the formation of the crop of green mass of corn, it was established that the growing season of this crop will take place against the background of significantly increased temperatures, especially at the end of the growing season. An increase in the amount of precipitation compared to the basic conditions is expected only at the beginning of the growing season. An increase in air temperature during the vegetation period will lead to a reduction of interphase periods and the vegetation period as a whole by 10%, which in turn may lead to a decrease in yield.