Abstract
Epiphytes are species that live and develop on other plants in the Mediterranean, the long
leaves of Posidonia oceanica represent an excellent support for a whole flora and fauna of
epiphytes. The objectives of this study are to:
1. Identification of the epiphytic species of Posidonia oceanica leaves
2. Measure the potential effects of effluent discharges on the epiphytic community of
Posidonia oceanica leaves.
Samples were taken during the summer of 2015 in an autonomous scapander, at the three
study sites (Anse de kouali, Bou Ismaïl, Tonic), 15 orthotropic beams of Po are randomly
collected and stored in formalin seawater at 5%. In our study, only 5 bundles per site were
treated. The study of the epiphytic population of Posidonia oceanica leaves collected at the
three study sites (Anse de kouali, Bou Ismaïl, Tonic) resulted in the identification of a total of
46 taxon, including 39 floristic taxa composed of 22 Rhodophyta , 14 Ochrophyta,
1Chlorophyta and 2 Cyanophy, and 7 faunistic taxa distributed in 3 Bryozoa, 2 Cnidaria, 1
Annelida and 1 Chordata. Macroalgae are qualitatively dominated by Rhodobionts
(Ceramiales) and quantitatively by Chromobionts (Ectocarpales). The specific richness S does
not show any differences between the inner and outer face of the leaves except for the Tonic
site where we recorded an S = 25 on the inner face and S = 12 on the outer face. this
difference can be explained by the very high turbidity, due to the numerous discharges that
line the coastline and, in particular, the discharges from the Tonic Emballage company. While
the overlap presents differences between the two faces at the level of the three sites. The
lowest R% is noted at Kouali which is probably due to the density and cover of the herbarium
at this site. At the level of the three sites, the adult leaves present a specific richness and a
greater epiphytic coverage than those of the intermediate leaves, the latter are less exposed
than the adult leaves, on the intermediate leaves generally only the encrusted species are
found. The sites located opposite the seafront of the agglomeration of Bou Ismaïl could be
individualized in relation to Kouali and especially Tonic, by their epiphytic composition but
also in terms of epiphyte overlap
Epiphytes are species that live and develop on other plants in the Mediterranean, the long
leaves of Posidonia oceanica represent an excellent support for a whole flora and fauna of
epiphytes. The objectives of this study are to:
1. Identification of the epiphytic species of Posidonia oceanica leaves
2. Measure the potential effects of effluent discharges on the epiphytic community of
Posidonia oceanica leaves.
Samples were taken during the summer of 2015 in an autonomous scapander, at the three
study sites (Anse de kouali, Bou Ismaïl, Tonic), 15 orthotropic beams of Po are randomly
collected and stored in formalin seawater at 5%. In our study, only 5 bundles per site were
treated. The study of the epiphytic population of Posidonia oceanica leaves collected at the
three study sites (Anse de kouali, Bou Ismaïl, Tonic) resulted in the identification of a total of
46 taxon, including 39 floristic taxa composed of 22 Rhodophyta , 14 Ochrophyta,
1Chlorophyta and 2 Cyanophy, and 7 faunistic taxa distributed in 3 Bryozoa, 2 Cnidaria, 1
Annelida and 1 Chordata. Macroalgae are qualitatively dominated by Rhodobionts
(Ceramiales) and quantitatively by Chromobionts (Ectocarpales). The specific richness S does
not show any differences between the inner and outer face of the leaves except for the Tonic
site where we recorded an S = 25 on the inner face and S = 12 on the outer face. this
difference can be explained by the very high turbidity, due to the numerous discharges that
line the coastline and, in particular, the discharges from the Tonic Emballage company. While
the overlap presents differences between the two faces at the level of the three sites. The
lowest R% is noted at Kouali which is probably due to the density and cover of the herbarium
at this site. At the level of the three sites, the adult leaves present a specific richness and a
greater epiphytic coverage than those of the intermediate leaves, the latter are less exposed
than the adult leaves, on the intermediate leaves generally only the encrusted species are
found. The sites located opposite the seafront of the agglomeration of Bou Ismaïl could be
individualized in relation to Kouali and especially Tonic, by their epiphytic composition but
also in terms of epiphyte overlap