CO{sub 2} availability, carbonic anhydrase, and the annual dinoflagellate bloom in Lake Kinneret
- Yigal Allon Kinneret Limnological Lab., Tiberias (Israel)
- Hebrew Univ., Jerusalem (Israel); and others
Changes with time in the concentration of inorganic carbon in Lake Kinneret subsurface water were followed throughout two seasonal dinoflagellate blooms. The response of natural populations of the dominant dinoflagellate, Peridinium gatunense, to these changes was recorded by examining fluctuations over time in the activity of the enzyme carbonic anhydrase (CA) and in photosynthetic parameters. Our results show distinct fluctuations of both external and cytoplasmic CA activity in P. gatunense throughout the annual bloom. Higher levels of activity were triggered by the decline of total dissolved inorganic C below 1.8 mM and more specifically by low concentrations of dissolved CO{sub 2} (1-10 {mu}M) during the seasonal bloom decline in May-June. Laboratory studies on cultured P. gatunense confirmed our field observations, suggesting that supplemental mechanisms are activated in P. gatunense that enhance inorganic C uptake when CO{sub 2} is limiting for photosynthesis. Eventually, the cellular adaptations of P. gatunense to the declining CO{sub 2} concentrations could not prevent decline of photosynthetic rates contributing to the subsequent decrease in P. gatunense biomass in May-June. In Lake Kinneret, P. gatunense is succeeded by Peridiniopsis spp., the photosynthetic rates and external CA activities of which were much higher under environmental conditions typical of the end of the bloom. 45 refs., 9 figs., 2 tabs.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 160111
- Journal Information:
- Limnology and Oceanography, Vol. 39, Issue 8; Other Information: PBD: Dec 1994
- Country of Publication:
- United States
- Language:
- English
Similar Records
Formation of dimethyloligosulfides in Lake Kinneret: Biogenic formation of inorganic oligosulfide intermediates under oxic conditions
Kootenay Lake Fertilization Experiment; Years 11 and 12, Technical Report 2002-2003.