Estimation of the Seasonal Dynamics of Abundance and Age Structure of the Southern Baikal Population of <i>Episсhura baiсalensis </i>Sars Using Variance Analysis
On the basis of the data obtained in collecting the zooplankton samples for 10-day periods in water layer 0-250 m during the years 2001-2004, the saeasonbal dynаmics of abundance and age structure of the natural population of <i>Episсhura baiсalensis </i>Sars<i>,</i> 1900 (Copepoda, Calanoida)<i> </i>from Southern Baikal was investigated. It was established by means of variance analysis that the seasonal changes of abundance and relations between nauplius, copepodites and mature individuals are statistically significant. By means of sample reduction, three phases of the population cycle were identified: growth, peak, and depression of abundance, corresponding to the three biological seasons. The importance of the data obtained for investigating the mechanisms of regulation of the number of population of <i>E. baiсalensis </i>is discussed