Praćenje stanja ihtiocenoza rijeke Save u Hrvatskoj u razdoblju od 2018. do 2021. godine

master's thesis

• Title (english): Monitoring the state of the ichthyocenoses of the Sava River in Croatia in the period from 2018 to 2021
• Author: Luka Marjanović
• Mentor: Tea Tomljanović (mentor)
• Committee member: Tea Tomljanović (predsjednik povjerenstva)
• Committee member: Daniel Matulić (član povjerenstva)
• Committee member: Ana Gavrilović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Fisheries, Beekeeping, Game Management and Special Zoology); Zagreb
• Defense date and country: 2023-09-25, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy

Abstract

Rijeka Sava je duž cijelog toka u Hrvatskoj izložena različitim antropogenim stresorima. Pregrađivanje toka, izgradnja nasipa, utvrđivanje obala, unos stranih vrsta te gospodarski i rekreativni ribolov imaju utjecaj na populacije zavičajnih vrsta. Cilj rada je bio usporediti ihtiocenoze različitih dijelova toka rijeke Save, procijeniti stanje stresa istraživanih lokacija te analizirati promjene u sastavu ihtiocenoza pojedinih lokacija. Redovno sustavno istraživanje ihtiofaune rijeke Save neophodno je za procjenu utjecaja antropogenih stresora u svrhu očuvanja zavičajnih vrsta slatkovodnih riba. Tijekom redovnog monitoringa Save bilježeni su podaci o ihtiofauni i bioraznolikosti riba za svaku godinu, no nedostajala je dublja analiza trendova promjena u ihtiocenozama kroz dulje razdoblje, kao i procjena stresa u zajednicama istraživanih lokacija. Podaci o ihtiofauni su prikupljeni u sklopu redovnog monitoringa rijeke Save u razdoblju od 2018.-2021. godine na lokacijama Medsave, Lijevi Dubrovčak, Jasenovac, Gornji Varoš i Slavonski Brod. Uzorak sa svake lokacije je izražen kao brojnost i biomasa riba na odsječku od 100 m. Uzorkovanje ribe se obavljalo elektroribolovom, a za svaku lokaciju su zabilježeni i osnovni fizikalno-kemijski parametri vode. Razlike izmedu ihtiocenoza različitih dijelova toka analizirane su ANOSIM (analysis of similarities) testom, a vrste koje naviše doprinose razlikama između lokacija i pojedninih godina za svaku lokaciju utvrđene su SIMPER (similarities percentage) analizom. Promjene u stanju stresa zajednica procijenjene su računanjem ABC (abundance biomass comparison) indeksa za svaku lokaciju i godinu istraživanja. Kruskal-Wallis analizom testirane su razlike u stanju stresa i bioraznolikosti izmedu pojedinih lokacija. Tijekom istraživanja zabilježeno je 26 vrsta riba koje su od ranije poznate za rijeku Savu. Lokacija Medsave se po sastavu vrsta najviše razlikovala od ostalih lokacija. Kretanje broja vrsta na lokacijama nije pokazalo stalni trend, već je brojnost vrsta nasumično varirala od godine do godine. Između lokacija nije zabilježena značajna razlika u indeksu bioraznolikosti i u stanju stresa.

Abstract (english)

Along its entire course, the Sava River in Croatia is exposed to different anthropogenic stressors. Partition channel construction, embankment construction, fortifying the coast, introduction of foreign species and commercial and recreational fishing have an impact on native species populations. The aim of this research was to compare the ichthyocenoses of different parts of the Sava River, to assess the state of stress in the investigated locations and analyze changes in the composition of the ichthyocenoses for individual locations. Regular systematic research of the ichthyofauna of the Sava River is necessary to assess the impact of anthropogenic stressors in order to preserve the native species of freshwater fish. Data on ichthyofauna and fish biodiversity were collected during regular monitoring of Sava River for each year, but more thorough trend analysis of changes in ichthyocenoses over a longer period, as well as assessment of stress in the communities of the researched locations was necessary. Data on ichthyofauna were collected as part of regular monitoring of the Sava River over the period of 2018 to 2021. at the locations of Medsave, Lijevi Dubrovčak, Jasenovac, Gornji Varoš and Slavonski Brod. Samples from each location show the abundance and biomass of fish on a 100 m section. The fishes were collected by electrofishing moreover, basic physical and chemical parameters of the water were also observed at each location. Differences between the ichthyocenoses of different parts of the stream were analyzed using ANOSIM (analysis of similarities) test and the species that contributed more to the differences between locations and individual years for each location were determined using SIMPER (similarities percentage) analysis. Changes in the stress state of communities were evaluated by calculating the ABC (abundance biomass comparison) index for each location and year of research. Kruskal-Wallis analysis tested differences in the state of stress and biodiversity between locations. During the research, 26 species of fish were found, all of which were known to inhabit the Sava River. Location Medsave differed the most from the other locations in terms of species composition. Number of species on the locations varied randomly from year to year, there was no constant trend. No significant difference was identified between the locations in the biodiversity index and the state of stress.

• Keywords: rijeka Sava; stanje ihtiocenoza; stres; zavičajne vrste
• Keywords (english): Sava River; state of the ichthyocenosis; stress; native species
• Language: croatian
• URN:NBN: urn:nbn:hr:204:434607
• Study programme: Title: Fisheries and Game Management; Study programme type: university; Study level: graduate; Academic / professional title: magistar/ magistra inženjer/inženjerka ribarstva i lovstva (magistar/ magistra inženjer/inženjerka ribarstva i lovstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to authenticated users
• Created on: 2023-11-10 13:23:03