Contrasting key roles of Ruppia cirrhosa in a southern Mediterranean lagoon: reservoir for both biodiversity and harmful species and indicator of lagoon health status.
The distribution of Ruppia cirrhosa meadow density and its epiphytic organisms in relation with environmental factors were studied in summer 2011 at five stations in the Ghar El Melh lagoon (GML; southern Mediterranean Sea). Eleven epiphytic groups were recognised among which diatoms and dinoflagellates were the dominant groups and greatest contributors to temporal dissimilarity. An overwhelming concentrations of harmful microalgae was recorded, mainly represented by the toxic dinoflagellate Prorocentrum lima with maximal concentrations attaining 6 × 10(5)cells 100g(-1) of Ruppia fresh weight. The epifauna community accounted for only 1.4% of total epiphyte abundance and was comprised predominantly of nematodes (47.51%), ciliates (32.59%), fish eggs (7.2%) and larvae (4.95%). PERMANOVA analyses revealed a significant spatio-temporal variation of all epiphytic groups (p<0.01). In this study, R. cirrhosa and its epiphytes were studied as potential early warning indicators of the health status of GML waters.
Université de Franche-Comté, Laboratoire de Chrono-Environnement, UMR CNRS 6249, France; Institut National des Sciences et Technologies de la Mer (INSTM), Laboratoire Milieu Marin, Centre la Goulette, Tunisia.
Amel
A
Dhib
Mounir
M
Ben Brahim
Souad
S
Turki
Lotfi
L
Aleya
D035961:Alismatales / Q000502:physiology*; D000818:Animals; D044822:Biodiversity; D004141:Dinoflagellida / Q000145:classification / Q000254:growth & development; D004784:Environmental Monitoring; D058865:Introduced Species; D008522:Mediterranean Sea; D010839:Phytoplankton / Q000145:classification / Q000254:growth & development; D012623:Seawater
Enviromental factors; Epiphytes; Ghar El Melh lagoon; Ruppia cirrhosa