Cycle populations dynamics of harmful insects
S.V. Stankevych*, L.V. Nemerytska, V.M. Polozhenets, L.V. Golovan, L.V. Zhukova, O.A. Molchanova, V.O. Melenti, L.A. Sirous, M.O. Filatov, H.V. Baidyk, I.P. Lezhenina, M.M. Dolya, M.D. Yevtushenko, I.V. Zabrodina, Ye.M. Biletskyj and I.V. Klymenko
We studied the reproduction cycles of 39 pest insect species and revealed that they, being cyclical and polycyclic in nature, are not strictly periodic and occur at different intervals. Moreover, we registered the outbreaks in their numbers in the periods with minimum and maximum of solar activity. The frequencies of the mass reproductions during the years of benchmarks were 2.5–3.0 times higher than the frequencies during the other years for the period of 1854–1985. We asserted that the synchronism of 70 species mass reproductions took place in Ukraine during some period with the years of sharp changes in the solar activity. The global synchronization of insect mass reproductions cannot be only explained by the weather factors since they are unlikely even within the same region. We suggested that the population cycles are self-oscillations of the biological systems synchronised by the solar activity, which can create the double effect: the “cyclic background” in the Earth changes and a part of the fractures of the long-term course distorting this “cyclic background”. The over helming majority of insect mass reproductions began in dry periods, and the droughts are synchronous with the dynamics of the solar activity. We believed that the cyclic character and recurrence are the universal properties of the development and functioning of any natural systems in space and time. This conclusion could be the conceptual basis for regularities in long-term recurrence of mass insect reproduction. Our idea of cyclic population dynamics reflects its descriptive, explanatory, prognostic and synthesizing functions and combines the previously proposed climatic and trophic theories. We developed the method and algorithms for a long-term forecast of insect mass reproductions on cyclic character of the population dynamics. According to the modern concepts of nonlinear dynamics (synergetics), the mass reproductions of insects are definitely programmed in present and future.