A Study of the Properties of the Multi-Step Recurrent Models for the Interannual Dynamics of Epiphytic Diatom Communities

Abstract

Communities of epiphytic diatoms develop seasonally. On macroalgae, they reach the highest density in the middle of summer and decline to a minimum value in winter. This discrete pattern makes it possible to use the tool of difference (recurrent) equations for testing the concept of density regulation on the interannual dynamics of the number of epiphytic diatoms. The properties of the obtained multi-step recurrent models for the interannual dynamics of the number of diatoms in the epiphyton of the macroalga Ulva lactuca Linnaeus collected from three areas of coastal waters in Peter the Great Bay, Sea of Japan (Amur Bay, Ussuri Bay, and Stark Strait), are considered. The proposed multi-step recurrent models do not contradict the primary data of observations. Each of the obtained descriptions for different water areas is characterized by its specific pattern of dynamics. The reproductive capacity of epiphytic diatom community is the lowest in the Stark Strait; the highest reproductive capacity is observed in Amur Bay. According to the models, the epiphytic diatom communities in different parts of Peter the Great Bay exhibit generally complex, pseudochaotic, dynamics of their number.