Opterećenje plastike i sedimenta bakterijama i metalima u tragovima na otoku Lastovu

master's thesis

• Title (english): Bacterial and trace metal load of plastic debris and sediment on the Lastovo Island
• Author: Ivan Lakuš
• Mentor: Kristina Pikelj (mentor)
• Mentor: Vlado Cuculić (komentor)
• Committee member: Kristina Pikelj (predsjednik povjerenstva)
• Committee member: Hana Fajković (član povjerenstva)
• Committee member: Zrinka Ljubešić (član povjerenstva)
• Committee member: Ivan Čanjevac (član povjerenstva)
• Committee member: Mladen Maradin (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Granter: University of Zagreb; Faculty of Science; (Department of Geology); Zagreb
• Defense date and country: 2023-09-22, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Plastični otpad i sediment mediji su za transport metala u tragovima te patogenih
bakterija u morskom okolišu, što ih čini prijetnjom za organizme i morske ekosustave, a na koncu i
za čovjeka. Cilj rada bio je odrediti opterećenje plastike i sedimenta metalima u tragovima te
bakterijama prije i poslije turističke sezone na Lastovu. Prvo su određene litološke značajke
sedimenata, a potom su FTIR-ATR metodom identificirani tipovi uzorkovanih polimera. Sediment
u uvali Uska šljunkoviti je pijesak s visokim udjelom karbonata (80% CaCO3), dok je sediment u
uvali Zace pijesak u kojem je najzastupljeniji kvarc (42% CaCO3). Najzastupljeniji tip polimera u
obje uvale je polipropilen (39%), a slijede ga polistiren (17%), polietilen niske gustoće (17%),
polietilen nepoznate gustoće (16%), te polietilen visoke gustoće (11%). Voltammetrijom su
određeni maseni udjeli metala u tragovima na plastici, odnosno u sedimentu. U sedimentu su
zabilježene veće vrijednosti ukupnih metala, ali unutar dopuštenih granica. Maseni udjeli metala na
plastici u rangu su neonečišćenih sedimenata. Primijećen je sljedeći trend masenih udjela metala na
plastici i u sedimentu: Zn > Pb > Cu > Cd. Afinitet vezanja metala s obzirom na tip polimera je:
LDPE > PS > PP > HDPE. Mikrobiološkom analizom je ustanovljeno veće opterećenje
heterotrofnim bakterijama na plastici i u sedimentu u post-sezoni. To bi mogao biti rezultat
turističke sezone. Sediment je pokazao veće opterećenje od plastike. U post-sezoni su u sedimentu
zabilježene i veće vrijednosti indikatora fekalnog onečišćenja, no unutar dopuštenih granica. U
sedimentu su identificirane vrste Vibrio alginolyticus i V. harveyi koje mogu biti patogene za
morske organizme i čovjeka. Polistiren se u ovom radu smatra bakterijama najopterećenijim
polimerom budući da su jedino na njemu uvijek narasle kolonije pojedinih HPC bakterija.

Abstract (english)

Marine plastic litter and sediment are transport media for trace metals and pathogenic
bacteria, which makes them a threat to living organisms and marine ecosystems, and ultimately to
humans. This work aimed to determine the load of MPL and sediment with TM and bacteria before
and after the tourist season on the island of Lastovo. Firstly, the lithological features of the
sediments were determined, followed by the identification of types of polymers using the FTIRATR. The sediment in the Uska cove is gravelly sand with a high carbonate content (80% CaCO3),
while the sediment in the Zace cove is sand with quartz being most abundant mineral (42%
CaCO3). The most common type of polymer in both bays was polypropylene (39%), followed by
polystyrene (17%), low density polyethylene (17%), unspecified polyethylene (16%), and high
density polyethylene (11%). Mass fractions of TM on MPL and sediment were determined by
voltammetry. The sediment showed higher values of total TM, but within the allowed limits. Mass
fractions of TM on MPL are in the range of unpolluted sediments. The following trend of mass
fractions of TM on MPL and in sediment was observed: Zn > Pb > Cu > Cd. Metal binding affinity
with regard to the polymer type was: LDPE > PS > PP > HDPE. Microbiological analysis revealed
a higher load of heterotrophic bacteria on MPL and in sediment in the post-season. This could be
the result of an exceptional tourist season. Sediment showed a higher bacterial load than MPL. In
the post-season, higher values of fecal pollution indicators were recorded in the sediment, but
within the permissible limits. The species Vibrio alginolyticus and V. harveyi, which can be
pathogenic for marine organisms and humans, were identified in the sediment. In this study,
polystyrene is considered to be the polymer most loaded with bacteria.

• Keywords: plastika; metali u tragovima; fekalne bakterije; onečišćenje; FTIR; voltammetrija
• Keywords (english): marine plastic litter; trace metals; fecal bacteria; pollution; FTIR; voltammetry
• Language: croatian
• URN:NBN: urn:nbn:hr:217:980382
• Project: Number: IP-2019-04-5832; Title: Međudjelovanje morskog (mikro)plastičnog otpada i metala zagađivala: mogući put od morskog okoliša do čovjeka; Title: Marine (micro)plastic litter and pollutant metals interaction: a possible pathway from marine environment to human; Acronym: METALPATH; Leader: Vlado Cuculić; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• Study programme: Title: Enviromental Sciences; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra struke znanosti o okolišu (magistar/magistra struke znanosti o okolišu)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2024-09-22
• Created on: 2023-10-18 11:21:46