PHYSIOLOGICAL RESPONSES OF ANABAENA VARIABILIS (CYANOPHYCEAE) TO INSTANTANEOUS EXPOSURE TO VARIOUS COMBINATIONS OF LIGHT INTENSITY AND TEMPERATURE¹

Abstract

Light intensity and temperature interactions have a complex effect on the physiological process rates of the filamentous bluegreen alga Anabaena variabilis Kütz. The optimum temperature for photosynthesis increased with increasing light intensity from 10°C at 42 μE·m−2·s−1 to 35°C at 562 μE·m−2·s−1. The light saturation parameter, IK, increased with increasing temperatures. The maximum photosynthetic rate (2.0 g C·g dry wt.−1·d−1) occurred at 35°C and 564 μE·m−2·s−1. At 15°C, the maximum rate was 1.25 g C·g dry wt.−1·d−1 at 332 μE·m−2·s−1. The dark respiration rate increased exponentially with temperature. Under favorable conditions of light intensity and temperature the percent of extracellular release of dissolved organic carbon was less than 5% of the total C fixed. This release increased to nearly 40% under combinations of low light intensity and high temperature. A mathematical model was developed to simulate the interaction of light intensity and temperature on photosynthetic rate. The interactive effects were represented by making the light‐saturation parameters a function of temperature.

Physiological ecology of a species of the filamentous green alga Mougeotia under acidic conditions: Light and temperature effects on photosynthesis and respiration

“…Most empirical models describe photosynthesis as a function of a single factor such as light (Jassby and Platt 1976;Steel 1978;Platt et al 1980) or temperature (Shugart et al 1974). In a few cases empirical models have included both irradiance and temperature (Lester et al 1974;Collins and Boylen 1982), but such combined models are mathematically cumbersome.…”

Temperature effects on photosynthetic capacity, respiration, and growth rates of bloom‐forming cyanobacteria

“…The effect of temperature on photosy an axenic culture of Anabaena variabili ied by Collins & Boylen (1982). P max inc to 35 °C but decreased rapidly thereaf noted a sharp drop in P max below 15 °C, the drop below 11 °C reported for Micwcystisfrom Lake Kasumigaura (Takamura et al 198 et al (1981), also using axenic cultures iabilis grown under 60uEm-2 s~1 ill examined the effect of temperature Arrhenius plots of the data indicated increased between 10 and 30 °C and that mum Pmax attained in the temperature achieved with cultures that had been pr< 27-29 °C.…”

Effects of Fluctuating Environments on the Selection of High Yielding Microalgae

“…In general, the cell quota for protein (44), carbon, nitrogen, and phosphorous all increase with temperature changes away from the optimum (45). Temperature and nutrient limitation interact to a lesser extent as the limitation becomes more severe.…”