Laboratory experiments to determine the limits of tolerance of flagellates to some abiotic factors

Summary

The ecological limits of tolerance of Ochromonas sociabilis nom. prov. Pringsheim (Chrysophyta, Chrysophyceae) to various pH values and temperatures were investigated in culture experiments. This species prefers acidic pH values and could be cultured for more than 2 weeks at values between 4 and 8. Maximal growth was observed at pH 6. The lower limit of temperature tolerance is the freezing point of the nutrient medium. The upper limit is at 35 °C. The highest population density was observed at 30 °C. The basic findings were confirmed by experiments in which various pH-temperature combinations were investigated.