Relationship between Temperature and Cyanobacterial Recruitment from Sediments in Laboratory and Field Studies

ABSTRACT

Cyanobacterial recruitment from sediments and its driving factors were studied in both a laboratory simulation and a field study in Lake Taihu (China) during March through June 2004. Microcystis aeruginosa constituted 95% of the cyanobacteria in the laboratory and field samples. In the laboratory, senescent cyanobacteria renewed growth between 5 °C and 9 °C and started recruitment to the water column at 14°C, while in Lake Taihu they simultaneously grew and left the sediment surface at 9 °C. We found a close correlation between algal recruitment and cumulative temperatures, in terms of the sum of effective temperatures, both in the laboratory simulation and the field study. Because recruitment is the result of algal growth, we assume cumulative temperature only indirectly drove cyanobacterial recruitment but directly promoted cyanobacterial growth to reduce ballast.