DigitalUM :: Browsing by Subject "Flora planctónica"

Now showing 1 - 1 of 1

Open Access
Fluctuación estacional de las poblaciones fitoplanctónicas del Estany de Cullera (Valencia)
(Universidad de Murcia, Servicio de Publicaciones, 1984) Rojo, C.; Miracle, María Rosa; Facultad de Biología
The seasonal fluctuations and the vertical distribution of the phytoplanktonic populations of the Estany of Cullera has been studied. The Estany of Cullera is a stratified coastal lagoon due to a marine water wedge underneath the flowing fresh water. The higher phytoplanktonic densities were found in winter and spring, in conditions of vertical mixing; being 86x109 ind/m2 the maximum density detected. In these seasons the diatoms were dominant; the most abundant species were Stephanodiscus subsalsus, Cyclotella meneghiniana & Cyclotella atomus. I n these periods m arine species can also be found such as Skeletonema costatum. Diatom dorninance is switched by the dorninance of green algae in summer, being the density then arround 8x1 09 ind/m2. In autumm, a remarkable minimum is produced due to an important water flux, reducing the phytoplanktonic density to 0.5~109 ind/m2. Most species are not found below the level of the chemocline where there ¡S a growth of photosynthetic bacteria. However, the existence of a few species of euglenoids, cyanobacteia and small flagellates has been detected in these botton water layers; they must have interesting adaptations to be able to live in the anoxic conditions of these waters.