MARINE STRATEGY MONITORING - PHYSICAL LOSS

In Italian seas, physical loss presents values between 15-16 km², detected respectively in the MRU Ionian Sea and Central Mediterranean and in the MRU Adriatic Sea (which measure 218,378 km² and 62,141 km² in extent, respectively) and the approximately 46 km² observed in the MRU Western Mediterranean Sea with an extent of 310,712 km² (Figure 1). It is generated by the following categories of works: cables, pipelines, port infrastructures, coastal defense works, offshore platforms and wells, wrecks, regasification terminals, wind farms (Figures 2a, 2b, and 2c). Directly related to the nature and characteristics of the works that generate it, physical loss presents a more uniform distribution near the coast, becoming irregular and sporadic as it moves offshore. In all MRUs, the category of work that most significantly impacts physical loss is port infrastructures, with values ranging from 54.6% (MRU Adriatic Sea) to 68.6% of total physical loss (MRU Western Mediterranean Sea). In the MRU Adriatic Sea, about 86% of the total physical loss is due to the combination of port infrastructures, coastal defense works, and pipelines, while in the other two MRUs (Ionian Sea and Central Mediterranean and Western Mediterranean Sea), port infrastructures and cables contribute respectively to 87.6% and 90% of the total physical loss. Specifically, Figure 2a (MRU Adriatic Sea) shows that the total physical loss, which amounts to 16.04 km², is mainly due to port infrastructures (54.6% corresponding to an extent of 8.75 km²), coastal defense works (21.3% corresponding to an extent of 3.42 km²), and pipelines (10.2% corresponding to an extent of 1.64 km²). In this MRU, an important contribution is also provided by wells and offshore structures (oil platforms and regasification terminals), which together contribute about 8% of the total physical loss (equal to 1.34 km²) and by cables (4.3%, with an extent of 0.69 km²). In the MRU Ionian Sea and Central Mediterranean (Figure 2b), 87.6% of physical loss is attributable to port infrastructures (62.2% for an extent of 9.26 km²) and cables (25.4% for an extent of 3.78 km²); the contribution of defense works, pipelines, and wrecks (respectively 5.3%, 3.4%, and 1.4%) provides a total extent of 1.52 km², while offshore platforms and wells contribute 2.2% of the total, corresponding to an extent of 0.33 km². Finally, the physical loss observed in the MRU Western Mediterranean Sea (Figure 2c), despite presenting greater extent values compared to those detected in the other MRUs, in line with the larger extent of the MRU, confirms a distribution by categories of works similar to that observed for the MRU Ionian Sea and Central Mediterranean, with the highest incidence of port infrastructures (68.6% of the total, with an extent of 31.27 km²), and cables (21.4% for an extent of 9.75 km²) and a more modest contribution provided by defense works (7.3% for an extent of 3.31 km²) and pipelines (1.7% for an extent of 0.79 km²). To calculate physical loss by habitat type, BHT (Broad Habitat Type) and OHT (Other Habitat Type), EUSeaMap 2021, EUNIS level 3 were examined. Specifically, for OHT, the Posidonia beds habitat, a priority habitat also protected under the Habitat Directive, was considered. As can be seen, in the MRU Adriatic Sea (Figure 3a), physical loss mainly affects infralittoral (Infralittoral sands) and circalittoral (Circalittoral mud) habitats, with values of 3.7 and 2.2 km², respectively (Figure 3a). On biogenic habitats represented here by Infralittoral rock and biogenic reef, Posidonia beds, and Circalittoral rock and biogenic reef, values of 0.3, 0.5, and 0.02 km² were observed, respectively. In this MRU, the works that most affect infralittoral habitats are defense works and pipelines; circalittoral habitats are mainly affected by pipelines and port infrastructures; finally, for the bathyal zone, cables are predominant (Figure 4a). In the MRU Ionian Sea and Central Mediterranean, physical loss mainly affects deep bathyal habitats (Bathyal sediment) with values of 2.89 km²; physical loss values exceeding 1 km² are also observed in infralittoral (Infralittoral sand) and circalittoral (Circalittoral sand) habitats with values of 1.64 and 1.15 km², respectively (Figure 3b). Regarding biogenic substrates, physical loss mainly affects infralittoral habitats (Posidonia Beds and Infralittoral rock and biogenic reef) with values of 0.26 and 0.32 km², respectively; other biogenic habitats (Circalittoral rock and biogenic reef, Offshore circalittoral rock and biogenic reef, and Bathyal rock and biogenic reef) present a total physical loss of 0.026 km² (Figure 3b). Port infrastructures and defense works are predominant in infralittoral habitats, while cables dominate in other zones (Figure 4b). Finally, in the MRU Western Mediterranean Sea, the highest physical loss values were found in both deep habitats (Bathyal sediment, with 6.45 km²) and abyssal habitats (Abyssal 1.91 km²) as well as in shallow habitats, such as Infralittoral sand, for which a physical loss of 4.82 km² was detected (Figure 3c). Regarding biogenic substrates sensu MSFD, physical loss mainly affects the Posidonia beds habitat (0.83 km²) and Infralittoral rock and Biogenic reef (0.96 km²); physical loss was also recorded with lower values in biogenic habitats of deeper zones (Circalittoral rock and biogenic reef, Offshore circalittoral rock and biogenic reef, and Bathyal rock and biogenic reef), contributing a total physical loss of 0.541 km² (Figure 3c). In this MRU, for almost all habitats, the greatest contribution to physical loss is constituted by cables, while for infralittoral habitats, the highest percentages of physical loss are associated with coastal defense works and port infrastructures (Figure 4c).