History of the community of planktonic Cladocera in Lake Glubokoe (Moscow Region)

Abstract

A 128-centimeter sediment core of a forest lake in the Moscow Region, for which the recent zooplankton has been well studied, was analysed. The changes in the density and size of organisms in the core points to an important role of fish and interspecific competition in Cladocera and to a minor role of invertebrate predators in the historical development of the plankton. No substantial shifts in the lake trophy seem to have occurred during the last 600 years. A widely used technique of heating the sediment in a 10°7o KOH solution may account for 5-13-fold losses of planktonic cladocerans' remains.

Temporal dynamics of invertebrate community assembly in Lake Victoria since the late Pleistocene based on chitinous remains

“…Sediment subsamples (~1 cm 3 ) of 1‐cm thickness for Cladocera analysis were collected along the length of the core ( n = 103; sampling intervals typically ranged from every 2 cm upcore to 15 cm downcore). The sediment was mixed with a 10% potassium hydroxide solution and heated to ~70°C for 10 min with gentle mixing to adequately separate cladoceran remains from other sediment particles and minimise further fragmentation (Frey, 1959; Matveev, 1986; Verbruggen et al., 2010). The mixture was subsequently washed through a 38‐μm mesh to remove finer materials.…”

“…The sediment was mixed with a 10% potassium hydroxide solution and heated to ~70°C for 10 min with gentle mixing to adequately separate cladoceran remains from other sediment particles and minimise further fragmentation (Frey, 1959;Matveev, 1986;Verbruggen et al, 2010). The mixture was subsequently washed through a 38μm mesh to remove finer materials.…”