Microbial community in the sediments of seagrasses Cymodocea nodosa and Zostera noltii in the coastal area of western Istria

Abstract

U ovom diplomskom radu analizirani su uzorci sedimenta, morskih cvjetnica i algi, te je određena brojnost mikrobne zajednice tijekom proljeća, ljeta i jeseni 2021. g., i to u uvalama Ribnjak, Funtana i Veštar na zapadnoj obali Istre. Karakteristike sedimenta u uvalama odraz su izloženosti taložnog okoliša i različitog donosa materijala s kopna. Stanje livada cvjetnica i s njime povezana brojnost mikrobne zajednice su pod utjecajem čovjeka i karakteristika sedimenta. Uvala Ribnjak je pod manjim antropogenim utjecajem, a sadrži muljevit sediment i očuvanu livadu cvjetnica. U uvali Veštar livada u karbonatnom pijesku je značajnije devastirana, vjerojatno radi turističkih aktivnosti, a mikrobna zajednica je najmanje zastupljena. Na uglavnom muljevitom dnu uvale Funtana livadu cvjetnica degradira utjecaj invazivne alge, a moguć je i utjecaj turističkih aktivnosti.In this thesis sediment, seagrass, and algae together with microbial abundancy were analysed in Ribnjak, Funtana, and Veštar Bays along the western Istrian coast during spring, summer and, autumn 2021. Sediment characteristics in all bays are the result of sedimentary environment exposure together with various inputs of terrigenous material. Seagrass meadow conditions and related microbial abundancies reflect the anthropogenic influence and sediment nature. Ribnjak Bay with muddy sea bottom and seagrass meadow in good condition is the least affected by human activities. Veštar Bay meadow, developed in carbonate sand, is significantly degraded, probably due to the tourism, while its microbial community is of the lowest abundance. Mostly muddy sea bottom of the Funtana Bay is covered by a partially degraded seagrass meadow, probably due to the competition of invasive algae, while touristic activities is not excluded