Promjena sastava zajednice riba rijeke Krke s naglaskom na utjecaj invazivnih vrsta

master's thesis

• Title (english): Changes in the composition of the ichthyocenosis of the Krka river with an emphasis on the impact of invasive species
• Author: Tin Škugor
• Mentor: Zoran Marčić (mentor)
• Mentor: Sven Horvatić (komentor)
• Committee member: Zoran Marčić (predsjednik povjerenstva)
• Committee member: Duje Lisičić (član povjerenstva)
• Committee member: Ana Previšić (član povjerenstva)
• Committee member: Ivana Maguire (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2023-09-18, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Cilj provedenog istraživanja bio je usporediti ihtiozajednicu rijeke Krke između razdoblja
2004. – 2008. i 2020. – 2023. te odrediti utjecaj invazivnih vrsta na zavičajne vrste riba.
Usporedbu ihtiozajednica kroz razdoblja proveli smo kroz kvalitativnu i kvantitativnu analizu
zabilježenih vrsta sveukupnog uzorka te šest uzorkovanih postaja pojedinačno. Pri usporedbi
ihtiozajednica također smo koristili i indekse raznolikosti, Cluster i Non-Metric MDS analize
te kategorije dominantnosti. Kako bi utvrdili utjecaj invazivnih na zavičajne vrste, analizirali
smo tri ekološke grupe zabilježenih vrsta koje su uspoređene između dva razdoblja. Također,
u svrhu analize utjecaja invazivnih na zavičajne vrste, usporedili smo dužinsko-masene odnose
i Fultonove kondicijske faktore zavičajne vrste drlje (Scardinius dergle Heckel i Kner, 1858) s
jedne postaje između dva razdoblja. Rezultati ukazuju kako postoje značajne razlike u sastavu
ihtiozajednice rijeke Krke između dva razdoblja, uslijed pojave stranih i translociranih vrsta te
da su one najizraženije na tri uzorkovane postaje koje se mogu opisati kao lentički sustavi.
Analiza ekoloških grupa ukazuje na istiskivanje zavičajnih vrsta pri kompeticiji sa stranim i
translociranim vrstama zbog dijeljenja istih resursa u okolišu. Analiza dužinsko-masenih
odnosa i Fultonovih kondicijskih faktora ukazuje na bolje stanje i kondiciju uzorkovane
populacije drlja u razdoblju 2020. – 2023. u odnosu na one uzorkovane u razdoblju 2004. –
2008.

Abstract (english)

The aim of this study was to compare the ichthyocenosis of the Krka River between two periods
of 2004 – 2008 and 2020 – 2023 and to determine the impact of invasive on native species. The
comparison of ichthyocenosis through periods was carried out through qualitative and
quantitative analysis of the recorded species of the overall sample and of the six sampled
stations individually. When comparing the ichthyocenosis, we also used diversity indices,
Cluster and Non-Metric MDS analysis and dominance categories. In order to determine the
impact of invasives on native species, we analyzed three ecological guilds of recorded species
that were compared between the two periods. Also, for the purpose of analyzing the impact of
invasives on native species, we compared the length-weight relationships and Fulton’s
condition factors of native species of dalmatian rudd (Scardinius dergle Heckel and Kner,
1858) from one station between two periods. The results indicate that there are significant
differences in the composition of the Krka River ichthyocenosis between the two periods, due
to the appearance of alien and translocated species and that they are most pronounced at the
three sampled stations which are described as lentic systems. The analysis of ecological guilds
indicates the displacement native species in competition with alien and translocated species
due to the sharing of resources in the environment. The analysis of length-mass relationships
and Fulton's condition factors indicates a better state and condition of the sampled population
of dalmatian rudds in the period 2020 – 2023 compared to those sampled in the period 2004 –
2008.

• Keywords: ihtiozajednica; strane vrste; translocirane vrste; ugroženost; Scardinius dergle
• Keywords (english): ichthyocenosis; alien species; translocated species; endangerment; Scardinius dergle
• Language: croatian
• URN:NBN: urn:nbn:hr:217:353370
• Study programme: Title: Experimental Biology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra eksperimentalne biologije (magistar/magistra eksperimentalne biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-10-17 11:23:26