Subject. The article addresses the influence of solar activity cycles on the stability of dynamics and fluctuations of winter wheat yields, on the Orel Oblast case. Objectives. The purpose of the study is to explore the relationship of solar activity in Wolf numbers with fluctuations in winter wheat yield; provide a quantitative measure of the relationship. Methods. We employed statistical methods for measuring trends in dynamics, established indicators of stability and fluctuation of yields, used time series correlation, the M. Kendall's method by the number of turning points to determine the type of fluctuations, tabular and graphical methods. Results. We presented time series of winter wheat yields for 1954–2022 (for 69 years). They include six 11-year cycles of solar activity. Taking into account the historical, socio-economic, agrotechnological conditions of development and achievements of breeding, we examined the time series of winter wheat yields for several periods. For 1954–2022, winter wheat yields increased 3.8 times, the average annual absolute increase was 10 times. The coefficient of determination confirmed that 11.2% of fluctuations in winter wheat yield were due to the influence of solar activity. Conclusions. The study of the variability of winter wheat yields showed that for 22-year cycles of solar activity, only 2% of yield fluctuations were due to differences in deviations of annual Wolf number levels from the average annual level.
Keywords: solar activity, Wolf number, winter wheat yield, indicators of yield stability and fluctuation, correlation coefficient
References:
Semenov M.I. [On the issue of patterns of fluctuations in yields]. Vestnik statistiki, 1922, vol. 11, no. 5–8, pp. 57–95. URL: Link vestnik_statistiki_1922_kniga_11_no5-8.pdf (In Russ.)
Yastremskii B.S. [The average level of Russian harvests and sunspots]. Vestnik statistiki, 1922, vol. 12, no. 9–12, pp. 79–86. URL: Link 63559/vestnik_statistiki_1922_kniga_12_no9-12.pdf (In Russ.)
Chizhevskii A.L. Kosmicheskii pul's zhizni: Zemlya v ob"yatiyakh Solntsa. Geliotaraksiya [The cosmic pulse of life: The Earth in the arms of the Sun. Heliotaraxia]. Moscow, Mysl' Publ., 1995, 768 p.
Chetyrkin E.M. Statisticheskie metody prognozirovaniya [Statistical forecasting methods]. Moscow, Statistika Publ., 1977, 200 p.
Yuzbashev M.M., Popova O.V., Manellya A.I. [Statistical methods for studying the relationship of yield fluctuations with cycles of solar activity]. Vestnik sel'skokhozyaistvennoi nauki = Bulletin of Agricultural Science, 1982, no. 8, pp. 56–64. (In Russ.)
Yuzbashev M.M., Manellya A.I. Statisticheskii analiz tendentsii i koleblemosti [Statistical analysis of trends and fluctuations]. Moscow, Finansy i statistika Publ., 1983, 207 p.
Tikhonov V.E., Neverov A.A. [Long-term forecast of crop yield on the basis of fundamental cycling of solar-planet relations]. Dostizheniya nauki i tekhniki APK =Achievements of Science and Technology of AIC, 2017, vol. 31, no. 4, pp. 62–67. URL: Link (In Russ.)
Tikhonov V.E., Neverov A.A., Kondrashova O.A., Abdrashitov R.R. [Impact of the Solar system planets on the dynamics of spring wheat yielding capacity in the Steppe Preduralye]. Izvestiya Orenburgskogo gosudarstvennogo agrarnogo universiteta = Izvestia Orenburg State Agrarian University, 2011, no. 2, pp. 18–21. URL: Link (In Russ.)
Mizun Yu.V., Mizun Yu.G. Tainy budushchego [Secrets of the future]. Moscow, Veche Publ., 2000, 592 p.
Manellya A.I., Nagnibedova N.N., Frenkel' A.A., Vashchukov L.I. Dinamika urozhainosti sel'skokhozyaistvennykh kul'tur v RSFSR [Dynamics of crop yields in the RSFSR]. Moscow, Statistika Publ., 1972, 192 p.
Kendall M. Vremennye ryady [Time Series]. Moscow, Finansy i statistika Publ., 1981, 199 p.