Archive | 2019
The Model of Dynamics of Population Number of the Plankton Cyclop Mesocyclops leuckarti (Copepoda), Based on Photoperiodism
Abstract
A model of Mesocyclops leuckarti population dynamics in a forest lake in Nord-Western Russia is described. The model is based on detailed phonological data that included the following information on copepod dormancy: density of resting stages in the lake sediments, rate of dormant stage reactivation in spring, active stage growth rate after diapause, accumulation rate of dormant stages in fall, and their survivorship during wintertime. Other important modeling parameters, such as critical photoperiodic response, percentage of diapausing stages versus day length, growth, and feeding rates for each development stage, and sensitivity to photoperiod stages, were estimated experimentally both in field and in lab. The model was verified with natural population of the species in Lake Kalishevskoe, Leningradskaya district, Nord-West of Russia. After verification, the model was used to test several hypotheses including effects of climate warming on copepod population density and accumulation of dormant stages in the end of summer. Increasing of diapausing copepodite stage density in the end of season was related to population density in the next year. The last amount was evaluated as population success obtained in competition with other zooplankton species.