Original paper

The comparison of ecological characteristics of Stichococcus (Chlorophyta) strains isolated from polar and temperate regions

Kvíderová, Jana; Lukavský, Jaromír

Abstract

Ecological characteristics, i.e. growth optima, upper and lower growth limits, of six Stichococcus strains were evaluated. Three strains originated from Svalbard, the Arctic, the next three ones from temperate regions. The ecological characteristics were evaluated by cultivation in the unit with crossed gradients of temperature (5 to 28°C) and light (170 to 1150 μmol.m−2.s−1). We studied growth in ten temperatures and five irradiances so 50 different combinations were obtained and compared. The strains originating from "cold" localities had significantly decreased lower temperature limit and optimum of growth, but no statistically significant difference was found in the upper growth limits. The differences in irradiance optima were not observed. The correlations between ecological characteristics and locality microenvironments were significant for low and optimum temperatures only.

Keywords

chlorophytastichococcuspolar regionstemperatecrossed gradientslighttemperaturegrowth rateoptimumlimit