Analisi delle comunita fitoplanctoniche dell'Adriatico Settentrionale mediante applicazione della metodologia statistica "Multi-Dimensional Scaling"

A research concerning the phytoplankton community of the Northern Adriatic Sea has been carried out in 1989. A statistical method, the "Non-metric Multi-Dimensional Scaling" (MDS), has been used to analyze phythoplankton data and to relate them to the environmental variables. Results showed that during summer, different communities were found in layers separated by the pycnocline, owing to the strongly stratified density structure of the water column. In winter, the geographical separation of floristical samples seemed to be due to different levels of dissolved nutrients (mainly nitrogen) that could be noticed respectively in the northern and in the southern area of the Venice Gulf. Finally, a comparison between MDS and PCA ("Principal Component Analysis") has been performed: the results show that PCA is less sensitive, being not able to discriminate the samples as well as MDS does.