Seasonal periodicity, heterocyst differentiation and sporulation of planktonic Cyanophyceae in a shallow lake, with special reference toAnabaena solitaria
Open Access
- 1 September 1984
- journal article
- research article
- Published by Taylor & Francis in British Phycological Journal
- Vol. 19 (3) , 245-257
- https://doi.org/10.1080/00071618400650271
Abstract
The periodicity of eight species of Cyanophyceae is recorded over two seasons in Sawley Dene, a 9·5 ha lake in North Yorkshire. The succession of blooms of heterocystous forms followed by colonial coccoid species is similar to that found in the epilimnion of many temperate eutrophic lakes that stratify in summer, though the Yorkshire lake is too shallow for thermal or chemical stratification to occur. The periodicity is explained by the long retention time of the lake, variable column stability and summer nitrogen deficiency, conditions that favour the larger self-regulating cyanophytes. Cell degeneration, heterocyst frequencies and akinete differentiation are discussed in relation to nitrate-nitrogen concentrations and population maxima. In the decline phase after a bloom, heterocystous forms show cell degeneration and akinete formation whereas the coccoid forms undergo sinking with little cell degeneration since intact colonies are necessary for overwintering in the sediment. Forty per cent of the akinetes of Anabaena solitaria germinate shortly after maturation and it is suggested that these akinetes serve to remove the alga from the upper and potentially damaging layers of the lake rather than persisting as long-term resting spores. Germinated akinetes may well constitute the major overwintering stage.This publication has 35 references indexed in Scilit:
- Some effects of artificial mixing on the dynamics of phytoplankton populations in large limnetic enclosuresJournal of Plankton Research, 1983
- Temporal and Spatial Scales in Phytoplankton Ecology. Mechanisms, Methods, Models, and ManagementCanadian Journal of Fisheries and Aquatic Sciences, 1980
- Planktonic blue‐green algae: Production, sedimentation, and decomposition in Lake Mendota, WisconsinLimnology and Oceanography, 1980
- Akinetes of the Cyanobacterium Nostoc PCC 7524: Macromolecular Composition, Structure and Control of DifferentiationJournal of General Microbiology, 1979
- Some physiological‐biochemical characteristics of planktonic blue‐green algae during bloom formation in three Salopian meresFreshwater Biology, 1979
- Sporulation and the development of planktonic blue-green algae in two Salopian meresProceedings of the Royal Society of London. B. Biological Sciences, 1977
- Nitrogen fixation in lakesPlant and Soil, 1971
- Special aspects of nitrogen fixation by blue-green algaeProceedings of the Royal Society of London. B. Biological Sciences, 1969
- Evidence of a Role of Heterocysts in the Sporulation of a Blue-Green AlgaAmerican Journal of Botany, 1966
- Control of sporulation in a blue-green algaDevelopmental Biology, 1965