摘要 : Planktonic organisms live in the pelagic zone of open waters and are adapted to survive in this turbulent environment. Some experimental results supported that a moderate turbulent intensity is beneficial for the function of the z... 展开 Planktonic organisms live in the pelagic zone of open waters and are adapted to survive in this turbulent environment. Some experimental results supported that a moderate turbulent intensity is beneficial for the function of the zooplankton (Saiz & Alcaraz 1991, 1992, Wisser & Stips 2002); however, above a critical turbulence value some organisms may suffer. Some research has hypothesized that the maximum body size of a planktonic organism cannot be larger than half the diameter of the smallest eddies occurring in a downward cascade of propagating eddies or organisms would get broken by the shear forces (Margalef 1978, Reynolds 1992, 1998, O'Brien 2002). Lake Balaton is the largest shallow lake in Central Europe, and the vertical space for the kinetic energy dissipation is very limited by its 3.25-m water column. Therefore, the estimated (Mackenzie & Leggert 1993) energy dissipation rate is high and the diameter of the smallest eddies are very small (6.19 10~(-5) cm~2 sec~3 and 0.33 mm, respectively, at the 3.2 cm sec~(-1) mean wind velocity in the lake area). The transient character of the vertical structure of zooplankton assemblages in Lake Balaton suggests that small-scale turbulence can be a major environmental factor for the vertical distribution and migration of the organisms in this kinetic lake. The aim of our study was to detect first the effect of the RMS turbulence (root-mean-square of the time series of the 3-D individual velocity magnitude values) on the vertical segregation and diurnal migration of zooplankton assemblages in the lake. 收起