The studies were conducted to quantitatively assess the impact of changes in the main agroclimatic resources in different periods of vegetation on the formation of spring wheat yield in the Trans-Ural steppe. The data for 1966–2023 of the state meteorological stations of Bredy (Chelyabinsk oblast), Ak’yar (Republic of Bashkortostan), and Dombarovskii (Orenburg oblast); of the Federal State Statistics Service; and of field experiments were used. The grain yield of spring wheat in the Trans-Ural steppe was low (0.914 t/ha), unstable from year to year (variation coefficient was 42.9%), and depended on moisture and heat resources. The precipitation amount during the growing season varied greatly from year to year (52.2–89.5%). The annual precipitation remained virtually unchanged in the period from 1966 to 2023, but decreased in June, July, August, and September and increased in other months. A rise in the amount of precipitation per year and in some months of the year exerted a positive effect on the yield of spring wheat. The impact of precipitation in May and June was significantly positive (the correlation coefficients were 0.676 and 0.771, respectively), a rise in its amount in these months by 10 mm increased the yield by 0.132 and 0.214 t/ha, respectively, relative to its initial trend value. The mean annual air temperature in the Trans-Ural steppe for the period from 1966 to 2023 increased on average by 0.038°C per year. Its rise was the greatest in January, February, March, August, and October. Climate warming in the Trans-Ural steppe exerted a negative effect on the formation of the spring wheat crop. An increase in air temperature by 1°C per month caused a decrease in the grain yield of the crop by 0.140 t/ha in May, by 0.109 t/ha in June, and by 0.041 t/ha in July.
Ismagilov et al. (Fri,) studied this question.