Salinity and temperature effects on the growth and chlorophyll-α content of some planktonic aigae

the effect of salinity (0-40 %o) and temperature (11-36oc, at 5oc intervals) variations on maximum growth rate (div d-1), maximum yield (logio cell number) and chlorophyll-α content (pg cell-1) of four planktonic algae was examined under laboratory conditions. phaeodactylum tricornutum grew over the entire range of experimental salinities, at 11-26 oc. the highest maximum growth rates ( 1.6 div d-1) occurred between 9-30 %o and 16-26 oc. optimum salinity range for maximum yield (7.0) was found at 9-35 %c, under 16 oc. tetraselmis gracilis reproduced from 4 to 40 %o at 11-31 oc, with the highest values of maximum growth rate ( 1.6 div d-1) and maximum yield (6.1) occurring at salinities between 14-40 %o at 11-21 oc and 11-16 oc, respectively. minutocellus polymorphic and chaetoceros sp grew between 9-40 %o and 11-31 oc. their highest maximum growth rates (2.1 and 2.6 div d-1, respectively) were found at 31oc, between 20-35 %o and 20-40 %o, respectively. the highest maximum yields for at. polymorphic (7.2) were recorded between 16-21 oc at 20-40 %o and for chaetoceros sp (6.8), between 25-40 %o at 16-31oc. chlorophyll-a content per cell was not conspicuously associated to temperature and salinity for the four species. at low salinity extremes, when cell division was inhibited, an increase in the amount of chlorophyll-a per cell was detected.