Statistical analysis of the distribution of infralittoral Cystoseira populations on pristine coasts of four Tyrrhenian islands: Proposed adjustment to the CARLIT index

Abstract

The influence of geomorphological features on the distribution of Cystoseira populations along the coasts of four pristine islands in the Tyrrhenian Sea (Italy, central Mediterranean) was studied by means of a model-based statistical analysis. The most relevant trait that determined the presence of these populations was found to be the coastline slope at the level of the infralittoral fringe. Our findings indicate that slopes above 60 • reduce the likelihood of Cystoseira communities. The effects of the coastline slope on the CARLIT index are considered and discussed in view of these findings. Pending further studies on the implementation of the CARLIT index in the Mediterranean basin, we suggest that any changes to the procedure or the hasty multiplication of reference sites be avoided, and instead propose a simple empirical adjustment of the EQ values to be able to more accurately monitor coasts with steep slopes using this index.

Assessment of the ecological status of Sicilian coastal waters according to a macroalgae based index (CARLIT)

“…Despite the absence of the species with the highest sensitivity level (C. amentacea), ES values belonging to the "good" class have been recorded also in this area within some water bodies. This outocome matched with the findings of a recent study according to which, in absence of anthropogenic pressures, the distribution of C. amentacea of the infralittoral fringe can be induced by the morphology of the coast, mainly related to the coastline slope [16]. Urbanization, including articialization of the coastline and sewage, are known to affect the very shallow communities, together with industrial impacts, as observed in many Mediterranean areas [5,6,19].…”

“…Urbanization, including articialization of the coastline and sewage, are known to affect the very shallow communities, together with industrial impacts, as observed in many Mediterranean areas [5,6,19]. Agricultural discharges and illegal domestic/urban outfalls are most likely responsible of a moderate to poor ES in some sectors of the Sicilian coastline (WB 5,15,16,17,22,23,24). However, only two water bodies (WB 16 and 24) did not yet fulfill the WFD requirements being classified as "moderate".…”

Mapping and Classification of Ecologically Sensitive Marine Habitats Using Unmanned Aerial Vehicle (UAV) Imagery and Object-Based Image Analysis (OBIA)

“…For instance, we reported the presence of brown macroalgae (especially Cystoseira spp., Figure 8b-d). This species is very important along rocky coasts because well-developed Cystoseira belt communities indicate good water quality [67] and, in general, arborescent macro-algae forests covering temperate rocky reefs are a known habitat for juvenile fish [68]. On the other hand, the southern part of the P. oceanica meadow presented an impacted area (represented by dead "matte", Figure 8e-g) near to the port, probably due to the works for the expansion of the breakwater.…”

Ecological status improvement over a decade along the Ligurian coast according to a macroalgae based index (CARLIT)

“…The selection of a proper reference site is fundamental for the CARLIT Index calculation [2]. This index is widely used in the EU Mediterranean countries: Spain (Catalan coast [1], Alboran Sea [3]); France (Southern coast and Corsica [4]); Italy ([5], Ligurian Sea [2, 6], Gulf of Naples [7], Northwestern Adriatic Sea [8], Sardinia [9], Tyrrhenian islands [10]); Croatia (Northeastern Adriatic Sea [11], Malta [12]) and in three non-EU countries: Albania [13], Tunisia [14] and Lebanon [15].…”