Morfološke značajke, veličina populacije i ugroženost cretne breze (Betula pubescens Ehrh.) u Hrvatskoj

master's thesis

• Title (english): Morphological characteristics, population size and conservation status of downy birtch (Betula pubescens Ehrh.) in Croatia
• Author: Anita Petković
• Mentor: Antun Alegro (mentor)
• Committee member: Antun Alegro (predsjednik povjerenstva)
• Committee member: Martina Šeruga Musić (član povjerenstva)
• Committee member: Renata Matoničkin Kepčija (član povjerenstva)
• Committee member: Maria Špoljar (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2017-02-27, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Cretna breza (Betula pubescens Ehrh.) u Hrvatskoj dolazi na južnom rubu svog područja rasprostranjenosti, te spada u vegetaciju cretnih heliofilnih šikara. Zbog nestajanja svojih prirodnih staništa kritično je ugrožena svojta u flori Hrvatske. Cilj ovoga istraživanja bio je utvrditi recentnu rasprostranjenost i veličinu populacija cretne breze u Hrvatskoj, te hibridogene svojte (B. × aurata Borkh.), križanca između cretne i obične breze (B. pendula Roth). Istraživano je na jedine dvije poznate lokacije cretne breze u Hrvatskoj: u Botaničkom rezervatu ˝Đon Močvar˝ kod sela Blatuša (Banovina) i neposredno iznad Ludvić potoka, ispod sela Gradišće (okolica Samobora). Prebrojavanje jedinki pokazalo je da su populacije cretne breze u Hrvatskoj izrazito male i ugrožene; na području Ludvić potoka populacija broji svega tri, a na Đon Močvaru 63 jedinke, od kojih samo manji dio fruktificira. Hibridna (blatuška) breza zabilježena je samo na Đon Močvaru s ukupno 56 jedinki. Na temelju toga procijenjen je stupanj ugroženosti populacija cretne i hibridne breze u Hrvatskoj sukladno IUCN kategorizaciji. Dodatno su na temelju izmjerenih 10 morfoloških svojstava listova obične, cretne i hibridine breze utvrđene razlike u morfologiji, te predložen determinacijski ključ.

Abstract (english)

Downy birch (Betula pubescens Ehrh.) in Croatia is on the southern edge of its area of distribution and is member of bog vegetation. Due to disappearing of its natural habitats, it is considered a critically endangered species of Croatian flora. The aim of this research was to determine the recent distribution and population size of downy birch and hibridogenous taxon (B. × aurata Borkh.), a hybrid between downy and silver birch (B. pendula Roth) in Croatia. The research was performed on the only two known locations of downy birch in Croatia: in Botanical reserve „Đon Močvar“ near the village Blatuša (Banovina Region) and above the stream Ludvić potok, below the village of Gradišće (surroundings of town Samobor). The counting of the individuals revealed that populations of downy birch are extremely small and endangered; the population near Ludvić potok consists of only three, while population at Đon Močvar of 63 individuals, of which just a small number fructificate. Hybridogenous birch has been recorded only at Đon Močvar with 56 individuals. Based on this results, a risk status according to IUCN categorization for the populations of downy and hybridogenous birch in Croatia has been estimated. In addition, based on measured 10 morphological leaf characters of silver, downy and hybrid birch, morphological differences have been identified and the determination key has been proposed.

• Keywords: Betula pubescens; Betula × aurata; morfometrijska analiza; status ugroženosti
• Keywords (english): Betula pubescens; Betula × aurata; morphometric analysis; threat status
• Language: croatian
• URN:NBN: urn:nbn:hr:217:224306
• 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: 2017-04-20 09:56:56