Importance of hydrological parameters in the distribution of planktonic eggs and larvae in an upwelling zone (Imessouane Bay, Moroccan Atlantic Coast)

The present study aimed to evaluate the spring biodiversity of planktonic eggs and larvae in Imessouane Bay and to assess their variability according to the hydrological parameters of the environment. Twenty seven biological and hydrological samples were taken at three stations during a three-month period (March, April and May 2018). The qualitative study revealed the presence of 26 taxa, divided into six major groups, of those the Arthropod larvae were the most dominant (43.16%). The maximum abundances of planktonic eggs and larvae were recorded during May, as the richest month in terms of diversity (25 taxa). The principal component analysis of the hydrological parameters made it possible to define a temporal organization dominated by 3 groups. The canonical correspondence analysis exhibited that certain environmental parameters are essential factors for the functioning and the spatiotemporal variability of the planktonic communities.