Repository of the Department of Marine Studies at the University of Split
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Spatio-temporal distribution of early developmental stages of European anchovy along the eastern side of the Adriatic sea (Croatian fishing sea)
No full textInćun (Engraulis encrasicolus (Linnaeus, 1758)) je vrsta pelagiĉke ribe koja je rasprostranjena u cijelom Sredozemnom i Crnom moru, kao i uz istoĉnu obalu Atlanskog oceana, a živi u plovama. Mrijesti se više puta godišnje, od ranog proljeća do kasne jeseni. Ovaj diplomski rad prikazuje prostornu-vremensku rasprostranjenost 10 stadija jaja i liĉinki inćuna uz istoĉnu obalu Jadranskog mora, na podruĉju ribolovnog mora Republike Hrvatske. Uzorkovanja su provedena u lipnju i srpnju 2021. i 2022.godine tijekom dvije znanstveno-istraživaĉke ekspedicije MEDITS. Broj postaja u 2021. godini je iznosio 59, a u 2022. godini 80. Broj pozitivnih postaja, odnosno onih na kojima su pronaĊeni rani razvojni stadiji inćuna je bio 44 (74,58 %) za 2021.godinu, te 60 (75 %) za 2022. godinu. Brojnost jaja se kretala izmeĊu 1 i 80 jaja po postaji za 2021.godinu, te od 1 do 155 jaja po postaji za 2022. godinu. Uzimajući u obzir obje godine, najveća brojnost ranih razvojnih stadija inćuna je bila na postajama ĉija je dubina mora bila veća od 101 m. Raniji stadiji jaja su bili zastupljeniji u uzorcima prikupljenim prije podne, dok su stariji stadiji jaja bili nešto zastupljeniji u poslijepodnevnim uzorcima. Linearna regresijska analiza ukazuje na jako slabu povezanost izmeĊu abiotskih ĉimbenika (saliniteta i temperature) i abundancije jaja i liĉinki.The European anchovy (Engraulis encrasicolus (Linnaeus, 1758)) is a species of pelagic fish that lives in shoals and it is distributed throught the Medditeranean and the Black Sea, as well as along the eastern coast of the Atlantic Ocean. This species spawns multiple times a year, from the early spring to late fall. This master thesis shows the spatial-temporal distribution of all 10 stages of anchovy eggs and larvae along the eastern side of the Adriatic Sea (Croatian fishing ground). Sampling was carried out in June and July 2021 and 2022 within the scientific expedition "MEDITS".The number of stations in 2021 was 59, and in 2022 80. The number of positive stations (stations which contained samples with anchovy ichthyoplankton) was 44 (74,58 %) for 2021, and 60 (75%) for 2022. The number of anchovy eggs ranged between 1 and 80 eggs per station for 2021, and 1 to 155 eggs per station for 2022. Considering both years, the highest abundance of anchovy early life stages was noted on the station which sea depth was greater than 101 m. In general, samples collected before noon were more abundant with the youngest egg stages while the samples collected after noon were more abundant with older egg stages. The linear correlation between abiotic parameters such as salinity and temperature and the abundance of eggs and larvae revealed a notably weak relationship
Određivanje optimalne neuronske mreže za klasifikaciju virusne populacije
No full textKlasificirana je virusna populacija u vodenom stupcu na srednjem Jadranu pomoću umjetne
neuronske mreže. Najbolja klasifikacija se postiže kada se kao ulazni parametri koriste
brojnosti eukariota i prokariota te temperatura mora kao okolišni parametar. Rezultati će se
naknadno povezati s ostalim okolišnim čimbenicima. U radu su modelirane virusne populacije
i različiti okolišni parametri. Testirana je važnost biotičkih varijabli bitnih za klasifikaciju
virusne populacije te varijabilnost unutar nje same. Korištenjem Neural gas metode s
različitim brojem neurona povećava se varijabilnost, a bojama se označavaju odstupanja od
srednje vrijednosti. Testiranjem Neural gas modela uočava se pojava nelinearnosti virusne
populacije povezane s temperaturom. Vremensko-prostorna analiza prikazuje raspodjelu
neurona u vodenom stupcu kroz cijelu godinu.Virus population in water column in the central Adriatic Sea was classified by artificial neural
network. The best classification is achieved when we use temperature, eukaryotes, and
prokaryotes as parameters, which are associated with environmental factors. In this thesis
virus populations were classified additionally with all parameters related to them. We have
tested importance of biotic variables important for virus population classification and
variability within the virus population itself. Using the Neural gas method with different
number of neurons we increase variability, while colouring signifies deviations from mean
value. Testing Neural gas models shows non-linearity of the virus population as a function of
temperature. Spatio-temporal analysis shows distribution of neurons within water column
throughout whole year
Associations between fishes and medusae
No full textU radu su predstavljeni fakultativni simbiotski odnosi različitih vrsta riba i meduza iz reda Schypozoa. Odnosi koji ostvaruju ribe i meduze mogu biti obostrano korisni (mutualizam), korisni samo za jednu vrstu (komenzalizam), a u nekim slučajevima je odnos koristan za jednu, a štetan za drugu vrstu (parazitizam). U svrhu ostvarivanja takvih odnosa, ribe i meduze su razvile različite mehanizme prepoznavanja sustavom bočne pruge ribe i kemijskim spojevima koje meduza ispušta u okolinu. Meduze kao domaćini ribama osiguravaju zaštitu od predatora, hranu (plankton, dijelovi tkiva meduza i parazitski račići koji žive na meduzama) te sigurno stanište za razvoj ličinki i juvenilnih stadija riba što uvelike doprinosi uspjehu regrutacije tih ribljih vrsta. Potencijalna korist meduza od ovakvog odnosa je uklanjanje ektoparazitskih amfipoda i detritusa s nabora usta.The thesis presents facultative symbiotic relationships of different species of fish and medusae from the order Schypozoa. Relationships between fish and jellyfish can be mutually beneficial (mutualism), beneficial only for one species (commensalism), and in some cases the relationship is beneficial for one species and harmful for the other (parasitism). In order to achieve such relationships, fish and medusae have developed different recognition mechanisms with the lateral line system of the fish and the chemical compounds released by the medusae into the environment. Medusae as hosts provide fish with protection from predators, food (plankton, parts of jellyfish tissue, and parasitic shrimps that live on jellyfish) and a safe habitat for the development of larvae and juvenile stages of fish, which greatly contributes to the success of the recruitment of these fish species. A potential benefit of jellyfish from this relationship is the removal of ectoparasitic amphipods and detritus from the folds of the mouth
Therapeutic use of microorganisms
No full textVeć dugi niz godina mikroorganizmi se primjenjuju u liječenju različitih zdravstvenih smetnji i
bolesti. Istraživanja na tom području pokazuju da primjena mikroorganizama ima potencijal i u liječenju
smrtonosnih bolesti uključujući i različite oblike karcinoma. Bakterije s probiotskim djelovanjem se
vrlo često koriste u tretiranju probavnih smetnji kao što je proljev, ali u novije vrijeme razvijene su i
nove skupine lijekova na bazi fotosintetskih bakterija sposobnih za proizvodnju ljekovitih tvari, kao što
je koenzim Q10, koje se primjenjuju u liječenju srčanih bolesti ili za detekciju raka. Mnoga istraživanja
ukazuju na to da primjena bakterija kao što su Escherichia coli i Streptomyces sp. može biti uspješna u
liječenju raka. Isto vrijedi i za viruse koji se još primjenjuju i u liječenju bakterijskih oboljenja.
Bakteriofagi su se pokazali kao jedna od najboljih opcija za uklanjanje bakterija otpornih na antibiotike,
dok su virusi poput adenovirusa (Ad), herpes simplex virusa 1 (HSV1) i myxoma virusa vrlo učinkoviti
u liječenju raka. Gljivice su među najboljim izvorima antibiotika od kojih je najpoznatiji penicilin. Kroz
različita istraživanja utvrđeno je da mikroorganizmi imaju visok potencijal u liječenju i
najsmrtonosnijih bolesti. U ovom završnom radu dan je prikaz istraživanja različitih mikroorganizama
koji imaju potencijal u primjeni liječenja raznih bolesti.Microorganisms have long been used to treat diseases, but there is various research proving that
they could be used to treat various deadly diseases, including different types of cancerous diseases.
Bacteria have often been used as probiotics against digestive diseases such as diarrhoea, but in recent
years photosynthetic bacteria that can be produced substances like coenzyme Q10 have been used to
treat heart disease and potentially used to detect cancer. Through many studies, it has been revealed that
bacteria such as Escherichia coli and Streptomyces are a potential cure for cancer. Viruses have long
been the basis of various research that focuses on their potential to treat cancer and bacterial diseases.
Bacteriophages are one of the best options for treating antibiotic-resistant bacteria, while viruses such
as adenoviruses (Ad), herpes simplex virus 1(HSV1) and myxoma viruses are primary candidates for
cancer treatment. Fungi are one of the best sources of antibiotics, the most famous of which is penicillin.
Through various studies, it has been established that microorganisms have great potential in the
treatment of even the most dangerous diseases. In this thesis a review on various studies of
microorganisms (bacteria, viruses, fungi, etc.) with potential application in therapeutic methods is
given
Different swimming styles in fish
No full textU ovom završnom radu su predstavljena glavna svojstva vode kao medija za kretanjerazličitih vrsta riba kao i sile koje djeluju na pojedinu vrstu. Za pokretanje ribe koristeperaje kako bi stvorile potisak tj. silu koja ih pokreće prema naprijed. Postoji nekolikovrsta peraja koje pomažu u kretanju; parne trbušne i prsne peraje te neparne leđna, podrepna i repna peraja. Razlikuju se dvije vrste plivanja kroz vodeni medij. Uprvuskupinu spadaju vrste riba koje za plivanje koriste pokretljivost tijela i/ili repnu peraju, a u drugu skupinu vrste koje se koriste neparnim (leđnom i podrepnom) i/ili parnim(trbušnim i prsnim) perajama. Stilovi plivanja i vrste koje karakteriziraju ove skupinepokretanja su detaljno opisani u ovom radu.This final thesis presents the main properties of water as a mediumfor different fishspecies as well as the forces that act on each species. To move fish use fins to createthrust; the force that propels them forward. There are several types of fins that aidinlocomotion; paired ventral and pectoral fins, non-paired dorsal, anal and caudal fins. There are two types of swimming trough the water medium. The first group includes
fish species that use body mobility and/or caudal fins for swimming, and the secondgroup includes species that use non-paired (dorsal and caudal) and/or paired (ventral
and pectoral) fins. The swimming styles and types that characterize these groups of
locomotion will be explained in detail in in this thesis
Floods in Venice
No full textU ovom radu predstavljeni su atmosferski i oceanski utjecaji na problem relativnog porasta
razine mora, a time i poplava, te načini na koje oni predstavljaju velike probleme za Veneciju i
ostatak svijeta. Veliki utjecaj na porast razine mora ima globalno zatopljenje i otapanje polarnih
ledenih kapa, što je posljedica antropogenog djelovanja. Također, vertikalno pomicanje tla te
rijetki atmosferski i oceanografski događaji ključni su faktori za nastanak poplava na mnogim
obalnim područjima poput Venecije. Velika poplava u Veneciji iz 1966. godine bila je svojevrsni
uvod u ono što je uslijedilo u listopadu 2018. i studenom 2019. godine. Na žalost takve pojave
će biti učestalije u budućnosti. Destruktivna poplava iz 1966. godine je prouzrokovala značajne
štete koje su potaknule Venecijance na izradu sustava obrane od poplava. Zbog toga pokrenut
je projekt MoSE , sastavljen od sustava mobilnih brana na tri lokacije Venecijanske lagune kako
bi zaštitio Veneciju od poplave.This thesis presents the atmospheric and oceanic influences on the problem of relative sea level
rise, and thus floods with the ways in which they represent major problems for Venice and the
rest of the world. Global warming and the melting of the polar ice caps have a major impact on
the sea level rise, which in turn is the impact due to anthropogenic activity. Also, vertical soil
movement, subsidence, atmospheric anomalies, oceanic fluctuations and astronomical
oscillations have a great potential of flooding for many coastal areas such as Venice. The great
flood of 1966. was a turning point for what later followed in October 2018. and November
2019., and what we can expect again in the near future. Destructive floods brought significant
damages that encouraged the Venetians to create a flood defense system. In this way, the MoSE
project was launched, consisting a system of mobile dams at three locations in the Venetian
lagoon to protect Venice from flooding
The EFFECT OF THE gROWING SEASONS ON CHEMICAL COMPOSITION AND BIOLOGICAL POTENTIAL OF SELECTED BROWN SEA WEEDS FROM THE ADRIATIC
No full textSmeđe alge su rasprostranjen, nedovoljno istražen i iskorišten te ekonomski vrijedan prirodni resurs. Prepoznate su kao izvor različitih skupina spojeva s dokazanim biološkim aktivnostima (antibakterijska, antioksidacijska, antiviralna, antitumorna, citotoksična aktivnost, itd.). Kemijski sastav algi ovisi o brojnim ekološkim čimbenicima koji variraju tijekom sezone rasta, o uvjetima predobrade algalnog materijala kao i različitim parametrima ekstrakcijskog procesa. U ovom istraživanju optimizirane su metode sušenja i odabrani uvjeti zelenih postupaka za ekstrakciju bioaktivnih tvari iz alge Padina pavonica s ciljem povećanja prinosa fenolnih spojeva, a time i njihove antioksidacijske aktivnosti. Metoda liofilizacije je odabrana kao najbolja metoda sušenja dok su se ekstrakcije potpomognute mikrovalovima i ultrazvukom pokazale učinkovitijima za dobivanje ekstrakata snažne biološke aktivnosti s višim sadržajem fenolnih spojeva. Po prvi put, izolirani ekstrakt P. pavonica korišten je za razvoj bioaktivnog premaza za filmove od polilaktične kiseline čime je potvrđen potencijal primjene ove alge u ambalažnim materijalima koji se koriste u prehrambenoj industriji. Kemijski sastav i biološka aktivnost algi Cystoseira compressa i P. pavonica pokazali su varijabilnost kroz sezonu rasta. Najviši sadržaj ukupnih fenolnih spojeva i najsnažnija antioksidacijska aktivnost zabilježeni su kod uzoraka branih u lipnju, a najveća antimikrobna aktivnost dokazana je za one brane u lipnju, srpnju i kolovozu, kada su izmjerene najviše temperature mora. Kemijski profil eteričnog ulja alge C. compressa mijenjao se sa sezonom rasta. Najviši udio masnih kiselina zabilježen je u svibnju i lipnju, dok je u srpnju i kolovozu zabilježen najviši udio alkohola. Istražen je i utjecaj postupka sušenja i sezone rasta na sastav hlapljivih organskih spojeva alge Halopteris scoparia. Uzorci svježih algi su se značajnije razlikovali kroz mjesece uzorkovanja u odnosu na uzorke suhih algi. U uzorcima vršnih para su dominantne skupine spojeva svježih i suhih algi bili alifatski spojevi i derivati benzena dok su u hidrodestilatima svježih algi najzastupljeniji bili alifatski spojevi u svibnju i rujnu te terpeni u lipnju, srpnju i kolovozu. Temeljem navedenog, rezultati ovih istraživanja ukazuju na činjenicu da su smeđe alge Jadranskog mora izvor bioaktivnih spojeva s potencijalnom primjenom u prehrambenoj i farmaceutskoj industriji.Brown seaweeds are abundant, underexplored, underused and economically valuable natural resource. They are recognized as a source of various compounds with proven biological activity (antibacterial, antioxidant, antiviral, antitumor, cytotoxic activity, etc.). The chemical composition of seaweeds depends on a number of environmental factors that vary during the seasonal growth, on the pre-treatment of algal material and on the extraction parameters. In this study, the drying methods and the selected conditions of the green procedures for the extraction of bioactives from Padina pavonica were optimized with the aim of increasing the yield of phenolic compounds and its antioxidant activity. Freeze-drying was chosen as the best drying method, and extractions assisted by microwaves and ultrasound were found to be the most suitable to obtain extracts with strong biological activity and higher total phenolic content. For the first time, P. pavonica extract was used to develop a bioactive coating for polylactic acid films, confirming the potential of this seaweed for the use in packaging materials for food industry. The chemical composition and biological activity of Cystoseira compressa and P. pavonica showed variations throughout the growing season. The highest content of total phenolic compounds and the strongest antioxidant activity were found in June samples, and the highest antimicrobial activity in June, July and August samples, when the highest sea temperatures were recorded. The chemical profile of the C. compressa essential oil changed during seasonal growth. The highest percentage of fatty acids was recorded in May and June, while the highest percentage of alcohol was recorded in July and August. The influence of drying procedures and growing season on the composition of Halopteris scoparia volatile organic compounds was investigated. Fresh seaweed samples differed more significantly between sampling months than dry seaweed samples. In the headspace samples, the predominant groups of compounds of fresh and dry samples were aliphatic compounds and benzene derivatives, while in the hydrolats of fresh samples, aliphatic compounds were most represented in May and September and terpenes in June, July, and August. Brown seaweeds of the Adriatic Sea are a potential source of bioactive compounds that can be used in the food and pharmaceutical industrie
Fishing boats for hunting small and large blue fish
No full textU ovom završenom radu govori se o raznolikosti brodova za lov male i krupne plave ribe. U tu grupu plovila spadaju parangalaši, koćari i plivaričari pri čemu je poseban naglasak stavljen na karakteristike plivaričara. Ulov plivaričara čini oko 25% svjetskog ulova plave ribe. Plivaričari mogu osigurati veliki ulov na jedinici ribolovnog napora i minimalnu potrošnju goriva po toni ulovljene ribe. Ovisno o rasporedu palubno – ribolovne opreme izdvajaju se različiti tipovi plivaričara: plivaričar sjeverno – američkog tipa, plivaričar tunolovac, plivaričar europskog tipa, plivaričar – koćar i plivaričar sa bubnjem. Plivaričar tunolovac cilja tunu i njene srodnike, dok se ostali plivaričari bave lovom male plave ribe kao što su srdela i inćun. Način pronalaska jata plivaričare čini drugačijim od ostalih ribolovnih brodova jer koriste sonare.In this thesis, we talk about the variety of boats for fishing small and large pelagic fish. This group of vessels includes longliners, trawlers and purse seiner, while the primary focus in this thesis is on purse seiners.. The catch of purse seiners accounts for about 25% of the world´s catch of the fish. Purse seiners can ensure a large catch per unit fishing effort and minimum fuel consumption per ton of fish caught. Depending on the arrangement of deck-fishing equipment, different types of purse seiners are distinguished: north-American type, tuna purse seiner, purse seiner of the European type, purse seiner – trawler and purse seiner with drum. Tuna purse seiner targets tuna and species similar to tuna, while other boat are engaged in hunting small pelagic fish such as sardines and anchovies. Method of finding fish stocks is what makes purse seines different from other fishing boats as they use sonar
Characteristics of the invasive species stypopodium schimperi
No full textU ovom radu su predstavljena obilježja invazivne vrste smeđe alge Stypopodium schimperi (Kützing) Verlaque & Boudouresque 1991. Unesena je u Sredozemno more preko Sueskog kanala, ali se ne zna sa sigurnošću kada, jer je ispočetka često bila zamjenjivana za druge vrste. Danas je S. schimperi široko rasprostranjena u istočnom dijelu Sredozemnog mora, gdje se smatra invazivnom vrstom. U ovom radu opisujemo karakteristike vrste S. schimperi, njezin put do Sredozemnog mora, izvještavamo o prvom nalazu u Jadranskom moru, utjecaju na okoliš te mogućim daljnjim putevima širenja. S visokim godišnjim povećanjem pokrivenosti, velikom biomasom, potpunog obrastanja supstrata i velikih dimenzija talusa, ova vrsta ima potencijal postati jednom od najinvazivnijih bentoskih alohtonih vrsta u Jadranskom moru, ali i u zapadnom dijelu Sredozemnog mora.The paper presents the characteristics of the invasive species of brown algae Stypopodium schimperi (Kützing) Verlaque & Boudouresque 1991. It was first introduced into the Mediterranean Sea through the Suez Canal, but the exact time of introduction remains uncertain due to initial confusion with other species. Today, S. schimperi is widely distributed in the eastern Mediterranean and is recognized as an invasive species. The paper provides a description of S. schimperi, its pathway to the Mediterranean Sea, the first discovery in the Adriatic Sea, its environmental impact and potential methods of spreading. With significant annual growth, large biomass, complete substrate fouling and large thallus dimensions, this species has the potential to become one of the most invasive non-native benthic species in the Adriatic Sea, but also in the western Mediterranean Sea
Oceanografske karakteristike Jadrana dokumentirane rezultatima operativnih numeričkih modela (zima, 2011./2012. godine)
No full textU ovom radu su analizirane oceanografske karakteristike Jadrana zime 2011./12. godine uz korištenje
operativnih numeričkih modela. Analizirani i prikazani su podatci koji karakteriziraju zimu 2011./12.
na temelju hidrodinamičkog i biokemijskog operativnog modela programa Copernicus. U sklopu
projekta Hrvatske zaklade za znanost StAdriVAR klasificirali su se tipovi vjetra. Prikazani su tipovi
vjetrova koji pušu nad Sredozemljem, izdvojeni su tipični vjetrovi za to područje: bura i jugo. Svakom
tipu vjetra pridružen je gubitak energije prema opisanim komponentama. Navedene su četiri
komponente koje objašnjavaju izmjenu energije tijekom ekstremne zime 2011./12., a to su: dolazno
kratkovalno zračenje, povratno dugovalno zračenje, evaporativni ili latentni prijenos energije i gubitak
energije vođenjem. Potom se analizira vremenska promjena svih komponenti izmjene energije. Nakon
prikaza oceanografsko-atmosferskih procesa prikazani su termohalini uvjeti u Jadranskom i Jonskom
moru. U radu su analizirani i termohalini uvjeti u proljeće i ljeto 2012. godine.This thesis analyzes oceanographic characteristics of the Adriatic Sea during the winter of
2011/12 using operational numerical models. The data characterizing the winter 2011/12 were
analyzed and presented based on the hydrodynamic and biochemical operational model of the
Copernicus program. As part of the StAdriVAR project of the Croatian Science Foundation,
wind types were classified. The wind types blowing over the Mediterranean Sea were presented.
The typical winds for this area the Bura and the South wind were highlighted. Each type of wind
was associated with a loss of energy corresponding to the components described previously.
Four components were listed that explained the energy exchange during the extreme winter of
2011/12, namely incoming shortwave radiation, return longwave radiation, evaporative or latent
energy transfer, and conduction energy loss. The temporal variation of all components of the
energy exchange was analyzed. After the oceanographic-atmospheric processes, the
thermohaline conditions in the Adriatic and Ionian seas were presented. The thesis also analyzed
the thermohaline conditions in spring and summer 2012