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U ovom radu prati se stanje koraligenske biocenoze i pripadajućih vrsta na 8 različitih postaja u Nacionalnom parku Mljet. Raznolikost vrsta na istraživanim postajama koraligenske biocenoze je prilično velika, te je na istraživanim postajama određeno je 415 vrsta alga i životinja. Najveća sličnost među vrstama utvrđena je između postaja Rt Lenga i Vranji Škoj (95,75%), Rt Lenga i Velika priveza (95,14%), te Hrid Štit i Korizmeni Rat (po 94,98% sličnosti). Koraligenska biocenoza je široko rasprostranjena uz istočnu stranu Jadranskog mora, prvenstveno na vanjskim otocima i pod jakim je negativnim utjecajem povišene temperature mora uslijed globalnih klimatskih promjena. Izmjerene temperature mora na postaji Rt Lenga na dubinama od 30 do 50 metara pokazuju trend temperaturnih anomalija tijekom ljetnih mjeseci. Najviše su ugroženi kameni koralji Madracis pharensis i Leptopsammia pruvoti, te crveni koralj Corallium rubrum. Populacije crvenog koralja (C. rubrum) su ugrožene i ilegalnim vađenjem, te previsokim temperaturama mora na dubinama ispod 40 metara. Vrsta Leptopsammia pruvoti ima velik postotak uginulih jedinki na istraživanim postajama (preko 30%). Koraligenska biocenoza u podmorju Nacionalnog parka Mljet je dobro očuvana, uz manji negativni antropogeni utjecaj (prvenstveno ribolovni alati i onečišćenje mora). Glavni problem su ipak klimatske promjene koje uzrokuju temperaturne anomalije na većim dubinama (između 30 i 50 metara dubine). Invazivne vrste također predstavljaju prijetnju za koraligensku zajednicu, a najveći problem trenutno predstavljaju Caulerpa cylindracea, Hermodice carunculata i Sparisoma cretense. Na istraživanim postajama pronađene su ribolovne mreže koje oštećuju sesilne vrste koraligena (alge i životinje) i nepovratno uništavaju vrste. In this paper, the state of the coralligenous biocenosis and associated species is monitored at 8 different stations in the Mljet National Park. The diversity of species at the researched stations of the coralligenous biocenosis is quite large, and 415 species of algae and animals were determined at the researched stations. The highest similarity among species was determined between the stations Rt Lenga and Vranji Škoj (95.75%), Rt Lenga and Velika priveza (95.14%), and Hrid Štit and Korizmeni Rat (94.98% similarity each). The coralligenous biocenosis is widely distributed along the eastern coast of the Adriatic Sea, primarily on the outer islands, and is strongly negatively influenced by increased sea temperatures due to global climate change. Sea temperatures measured at the Rt Lenga station at depths of 30 to 50 meters show a trend of temperature anomalies during the summer months. The most endangered are the stony corals Madracis pharensis and Leptopsammia pruvoti, and the red coral Corallium rubrum. Populations of red coral (C. rubrum) are also threatened by illegal fishing and excessively high sea temperatures at depths below 40 meters. The coral Leptopsammia pruvoti has a high percentage of dead individuals at the research stations (over 30%). The coralligenous biocenosis in the seabed of the Mljet National Park is well preserved, with less negative anthropogenic influence (primarily fishing tools and sea pollution). The main problem, however, is climate change, which causes temperature anomalies at greater depths (between 30 and 50 meters deep). Invasive species also pose a threat to the coralligenous community, and the biggest problem is currently represented by Caulerpa cylindracea, Hermodice carunculata and Sparisoma cretense. At the researched stations, fishing nets were found that damage sessile coralligene species (algae and animals) and irreversibly destroy the species. |
