Assessment of <i>Posidonia Oceanica</i> (L.) Delile conservation status by standard and putative approaches: the case study of Santa Marinella meadow (Italy, W Mediterranean)

Abstract

The conservation status of the Posidonia oceanica meadow at Santa Marinella (Rome) was evaluated through both standard (bed density, leaf biometry, "A" coefficient, Leaf Area Index, rhizome production) and biochemical/genetic approaches (total phenol content and Random Amplified Polymorphic DNA marker). The biochemical/genetic results are in agreement with those obtained by standard approaches. The bed under study was ranked as a disturbed one, due to its low density, and high heterogeneity in leaf biometry, LAI values, "A" coefficient and primary production. This low quality ranking is confirmed by both mean phenol content in plants, quite high and scattered, and by the low genetic variability in the meadow, with a very high similarity of specimen at a local scale. Hence, these two putative approaches clearly identify the endangered conservation status of the meadow. They link plant biodiversity and ecophysiology to ecosystem 'health'. Furthermore, they are repeatable and standardizable and could be usefully introduced in meadows monitoring to check environmental quality.

Ecophysiological Plasticity and Bacteriome Shift in the Seagrass Halophila stipulacea along a Depth Gradient in the Northern Red Sea

“…Total phenol content is considered a suitable indicator of the ecophysiological status of seagrasses (Migliore et al, 2007; Rotini et al, 2013), since seagrasses are known to modulate their phenol content in response to stressful environmental conditions (e.g., Rotini et al, 2011; Darnell and Heck, 2013; Silva et al, 2013; Arnold et al, 2014). The reduced phenol concentrations at 28 m may be related to a simultaneous reduction in the phenolic biosynthesis and increase of phenolic mobilization, both triggered by low light regimes.…”

Ecological Function of Phenolic Compounds from Mediterranean Fucoid Algae and Seagrasses: An Overview on the Genus Cystoseira sensu lato and Posidonia oceanica (L.) Delile

“…Among the Mediterranean seagrasses, P. oceanica is the most thoroughly investigated from the phytochemical point of view [6]. Several studies analyzed the role that phenolic compounds have in the response of P. oceanica to different environmental pressures: e.g., turbidity and pollution, ocean acidification, competition, pathogen infection and overgrazing [2,15,29,30,42,120,125,[131][132][133]. For instance, high phenol concentrations were found in P. oceanica leaves when exposed to contamination by metals and proximity to intensive fish aquaculture [42,134].…”

“…Since the changes in phenolic compounds represent a response to environmental stressors, they can be used to screen the P. oceanica health status during the regular monitoring programs carried out for management purposes [16,17,113,116,132,139,140]. Two promising tools (easy, rapid and inexpensive): phenolic compounds in rhizome and Random Amplified Polymorphic DNA (RAPD) markers in leaves, were recently proposed to monitor the health state of P. oceanica meadows [17,116,132]. In fact, phenolic compounds represent a generic response to different environmental stress related not only to extrinsic (seasons) and intrinsic (metabolism) factors, but also to the genetic variation of the plants.…”

Bioactive natural products from marine angiosperms: abundance and functions

“…Similarly, with the predominance of caffeic acid in the adult and intermediate leaves of P. oceanica, other phenolic compounds such as 4-hydroxybenzoic acid, 4-coumaric acid, trans-cinnamic acid, caffeic acid and a mixture of ferulic acid and ester methyl 12-acetoxyricinoleate were also reported 18 . The difference existing in both the free and bound phenolics of P. oceanica were estimated in samples collected from different geographic regions 19,20 . Similarly, phenol content is found to vary in different parts of rhizomes in P. oceanica 21 .…”