A good review of plankton compositions, cell sizes, etc can be found in Kiørboe, 1993, if you haven't read that already. Lower salinity waters should have larger phytoplankton.

Every phytoplankter has a temperature range in which it can best grow & multiply at an optimal level.If the values of temp. differ from this range,the volume goes down.Higher salinity usually lowers productivity,which is independent of minerals available in sea water.Lower the salinity,a plankter will increase its surface area.

You can refer the book:The Oceans by Johnson,Svedrup & Fleming for more information.

This a gerat question/Discussion Sir Mitra.

Watching both Sir Trivedi and Tilley suggestions, Now I have idea to combining them. I mean there's a possibly purpose to a specific thermal-based identification for sea surface zoning by remote sensing technique thought SST distribution.

For climate change monitoring purpose, perharp this approach can conducting by long series data change monitoring. Challenge and limitation for accuracy result maybe exist from available insitu data to confirm those series data. Others is concerning to best (high resolution) Satellite data set for both series and insitu check make posible for support the result.

Thank you very much for any suggestion later