Epiphyte assemblages of the Mediterranean seagrassPosidonia oceanica: an overview

Abstract

This paper reviews the main studies dealing with epiphytes of both leaves and rhizomes of Posidonia oceanica, the main seagrass found in the Mediterranean Sea. A total of 660 epiphyte species has been recorded, including 430 on leaves and 437 on rhizomes. Of these, 205 are Rhodophyta, and 19 Tunicata. The epiphyte assemblages demonstrate a gradient of dissimilarity from west to east, with the eastern area being the most unlike the others. The differences can be attributed mostly to rare species that differ amongst the Mediterranean regions. Many of the dominant taxa have been found in all meadows studied. Data concerning species composition, abundance, and patterns of spatial and temporal variability are summarized, and biotic and abiotic factors controlling the structure of assemblages are discussed. Responses of epiphyte assemblages to anthropogenic stressors, such as nutrient enrichment and biological invasions, are discussed in relation to the use of epiphytes as ecological indicators.Marine Ecology. ISSN 0173-9565

Effects of Costa Concordia shipwreck on epiphytic assemblages and biotic features of Posidonia oceanica canopy

“…Epiphytic foraminiferal populations usually respond to nutrient enrichment with a decrease in abundance, thus they may be useful indicators of ecosystem decline in subtropical-tropical, oligotrophic marine habitats (Richardson, 2006). Although these protozoans in surface sediments colonized by P. oceanica have been shown to be useful indicators to characterize a given environment in an integrated way (MateuVicens et al, 2014), no information is reported about the possible significant changes of foraminifers in leaf epiphytic assemblages colonizing disturbed meadows of P. oceanica (Piazzi et al, 2015). Therefore, further investigations should be carried out on the use of this taxon as bioindicator in epiphytic community studies on P. oceanica.…”

“…In this regard, increases in the epiphyte biomass, differences in their spatial heterogeneity, shifts in species composition, morphological groups and main taxonomic groups have been observed under human disturbance regimes (Balata et al, 2007;Ben Brahim et al, 2010;Martínez-Crego et al, 2010;Piazzi et al, 2004Piazzi et al, , 2015Ruiz et al, 2001).…”

“…Epiphytic community can be an indicator of the ecological quality of coastal waters (Piazzi et al, 2015), being more sensitive and reacting more rapidly than the host plant to alterations (Delgado et al, 1999;Giovannetti et al, 2010;Nesti et al, 2009). In this regard, increases in the epiphyte biomass, differences in their spatial heterogeneity, shifts in species composition, morphological groups and main taxonomic groups have been observed under human disturbance regimes (Balata et al, 2007;Ben Brahim et al, 2010;Martínez-Crego et al, 2010;Piazzi et al, 2004Piazzi et al, , 2015Ruiz et al, 2001).…”

Temporal and bathymetric variation of epiphyte cover and leaf biomass in a southern Posidonia oceanica (L.) meadow: the case of Mahdia coast, Tunisia

“…Biotic interactions, such as grazing and competition amongst sessile organisms, may be responsible for this small-scale variability (Alcoverro et al, 1997;Mazzella & Russo, 1989;Prado et al, 2007). The presence of rocky substrata close or interspersed with meadows may also constitute an important factor influencing smallscale patterns of distribution of epiphytic assemblages (Piazzi et al, 2016).…”

“…Epiphytes are known to be more sensitive to environmental changes than their plant hosts (Nesti, Piazzi, & Balata, ). For example, nutrient enrichment causes an increase in epiphyte biomass, changes in the invertebrate/macroalgae ratio and modifications to species composition (Piazzi, Balata, & Ceccherelli, and references within). Understanding the distribution of macroepiphytic species should be particularly helpful to design monitoring programs.…”