Naslov
Lokrum rocky shores and shallow bottoms- home of a variety of organisms
(Lokrumska obala i plitko podmorje - dom brojnih organizama)

Autori
Bratoš Cetinić, Ana ; Crnčević, Marija

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, prošireni sažetak, ostalo

Izvornik
Book of Abstracts Lokrum Island: From scientific knowledge to protected area management = Zbornik sažetaka Znanstveno- stručnog skupa Otok Lokrum: Od znanstvenih spoznaja do upravljanja zaštićenim područjem / Crnčević, M. ; Bratoš Cetinić, A. - Dubrovnik : Javna ustanova Rezervat Lokrum Public Institution Special Reserve of forest vegetation Island Lokrum, 2019, 78-79

ISBN
978-953-59566-2-4

Skup
Znanstveno-stručnoi skup Otok Lokrum: Od znanstvenih spoznaja do upravljanja zaštićenim područjem = Scientific and Professional Conference Lokrum Island: From scientific knowledge to protected area management

Mjesto i datum
Dubrovnik, Hrvatska, 07.11.2019. - 08.11.2019

Vrsta sudjelovanja
Poster

Vrsta recenzije
Recenziran

Ključne riječi
bentos ; bioraznolikost ; litoral ; Pinna nobilis

Sažetak
Marine environment is the most diverse environment on Earth with a wide range of properties. Besides providing diverse habitats to millions of species and various taxonomic categories, oceans affect terrestrial habitats, biosphere and atmosphere, regulating weather patterns and climate. Littoral, comparatively narrow and the most accessible part of the marine environment is significantly affected by land. During the warm season, Lokrum is visited daily by numerous tourists and local inhabitants, who observe not only terrestrial environment but marine environment as well. Due to the island’s location and mostly accessible limestone rocks, it is a good site to observe common Adriatic marine organisms in situ. In supralittoral zone located above high tide sea level line, which can reach up to 5 meters of height on Lokrum, organisms are mostly distributed horizontally forming belts parallel to the shoreline. Cyanobacteria form visible dark coating on the rocks. Besides, it is inhabited by periwinkles, barnacles and other crustaceans. In midlittoral zone (here 0.5m - 1m), waves and tides generate fluctuations of environmental conditions, so organisms are adapted to an extreme environment – the shore is not always submerged and most organisms are desiccation resistant and distributed unevenly. Since the upper midlittoral zone is inhabited by limpets, periwinkles, barnacles, and other crustaceans, lower midlittoral zone is more diverse and densely populated. This is particularly visible on exposed shores of Lokrum which are covered by red calcareous algae and provide refuge to a variety of invertebrates from different phyla. Brown algae are also found on regular basis. The most common animals such as limpets, chitons, gastropods, anemone are attached to the substrate or their movement is limited, as in sea urchins, crabs and molluscs. It is also home to shrimps. Below the low water line, environmental conditions are more stable. Well-lit shallow rocks are covered with abundant population of macroalgae. They are mostly brown, but green and red algae which are home to many species such as mussels, sea urchins, worms, molluscs, sponges, can be observed in this zone. Aa large variety of fish looking for prey can be observed in this area, too. Well- lit shallow sandy bottoms are covered by patches or large areas of seagrass Posidonia oceanica, endemic to the Mediterranean region. The meadows of Posidonia provide habitat and nutrition for many species of fish, crustaceans, molluscs, bryozoans, as well as for many species of algae. It is the most diverse Mediterranean biocenosis. It is light dependent, produces large quantities of oxygen, and removes carbon dioxide from the atmosphere. Among many species which live in Posidonia meadows, relatively abundant population of the bivalve Pinna nobilis, fan mussel could be observed here by 2019. Interestingly, it was even found among rocks. It seems, however, that the mass mortality events occurring in the western Mediterranean caused by a parasite in 2016 and spreading eastwards, reached the Adriatic in spring of 2019, and affected Lokrums' population. Further comprehensive research is needed to determine the state of this endemic and endangered species. Owing to accessibility and specific environmental conditions, the littoral zone is vulnerable to human impact. However, Lokrum Island is a special nature reserve and an area of Natura 2000 ecological network, which provides opportunities for education, monitoring and research of marine ecosystems.

Izvorni jezik
Engleski

Znanstvena područja
Biologija, Interdisciplinarne prirodne znanosti

POVEZANOST RADA