magistrsko delo
Gregor Simčič (Author), Marjetka Suhadolc (Reviewer), Ivan Kos (Mentor), Ivan Kos (Thesis defence commission member), Marjetka Suhadolc (Thesis defence commission member), Tomaž Skrbinšek (Thesis defence commission member)

Abstract

V raziskavi smo preverili primernost tako terensko pridobljenih kot tudi javno dostopnih podatkov o okoljskih spremenljivkah za modeliranje razširjenosti nekaterih vrst strig na območju Slovenije. Podatke o prisotnosti posameznih vrst ter njihovi gostoti smo pridobili z vzorčenjem po metodi kvadratov. Vzorčenje smo opravili na 4 lokacijah na območju Gorjancev. Naša raziskava je prvi sistematičen popis združb strig na tem območju. Skupno smo ujeli 656 osebkov, uvrščenih v 31 vrst. V analizo odnosov med pojavljanjem različnih vrst strig ter abiotskimi dejavniki smo vključili 11 okoljskih spremenljivk, ki opisujejo geografsko lego, klimatske značilnosti, lastnosti tal ter starost in strukturo gozda na območju raziskave. Prav tako smo podatke za omenjene okoljske dejavnike pridobili iz javno dostopnih podatkovnih baz institucij, ki v Republiki Sloveniji delujejo na širšem področju upravljanja z okoljem. Povezave med prisotnostjo različnih vrst strig ter okoljskimi spremenljivkami smo ugotavljali z multitvariatnimi statističnimi metodami, konkretneje z analizo redundance (RDA). Statistično analizo smo izvedli v dveh korakih: najprej smo v analizo vključili podatke o prisotnosti vrst ter podatke o terensko izmerjenih okoljskih spremenljivkah, nato pa smo za iste vrste izvedli še analizo s podatki o okoljskih spremenljivkah, pridobljenimi iz različnih javno dostopnih podatkovnih baz. Pri izboru okoljskih spremenljivk smo se poslužili metod avtomatskega izbora. Tako smo v končni model vključili izmerjene okoljske spremenljivke, ki opisujejo nadmorsko višino, delež organske snovi v tleh ter debelino listnega opada. Stopnja pojasnjene variance prisotnosti različnih vrst strig v odvisnosti od okoljskih spremenljivk je v obeh primerih zelo nizka, kar nakazuje na to, da nam v analizo ni uspelo vključiti okoljskih spremenljivk, ki bi zanesljivo opisovale razporejanje strig znotraj območja naše raziskave. Kot poglaviten razlog za nezanesljivost naših rezultatov lahko izpostavimo predvsem majhen vzorec, ki smo ga vključili v analizo. Kljub temu lahko izpostavimo, da so se kot bolj zanesljivi za snovanje tovrstnih modelov izkazali terensko izmerjeni podatki o okoljskih spremenljivkah. Kar je pričakovano glede na prostorsko merilo javno dostopnih podatkov. Prav tako naši rezultati nakazujejo, da so odnosi med okoljskimi spremenljivkami in pojavljanjem strig vrstno specifični.

Keywords

RDA;javno dostopni podatki;multivariatne statistične metode;modeli razširjenosti vrst;

Data

Language: Slovenian
Year of publishing:
Typology: 2.09 - Master's Thesis
Organization: UL BF - Biotechnical Faculty
Publisher: [G. Simčič]
UDC: 595.62(043.2)
COBISS: 5329487 Link will open in a new window
Views: 610
Downloads: 182
Average score: 0 (0 votes)
Metadata: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Other data

Secondary language: English
Secondary title: Suitability of public access and field-recorded environmental data for modelling centipede (Chilopoda) distribution
Secondary abstract: In this research we tried to assess the suitability of public access and field-recorded environmental data for modelling centipede distribution. We focused on the centipede assemblages of the Gorjanci hill range where four sampling sites were selected. Our research represents the first systematic survey of centipede assemblages in this part of Slovenia. Using the quadrant sampling method we collected 39 samples consisting of 656 individuals assigned to 31 species. For each sampling site, 11 environmental factors (describing geographical region, climate characteristics, soil properties, forest age and structure) were collected. The corresponding data was gathered from publicly available databases of the environmental management institutions of the Republic of Slovenia. We tried to evaluate the usefulness of this data, for species distribution modelling by comparing the results of redundancy analysis (RDA) based on the two different datasets: (i) one consisting of the data gathered from different databases and (ii) the other consisting of the data collected on the field. For the selection of environmental variables that were included in the final model we used automatic stepwise model building methods. So the final model includes environmental variables that describe elevation, soil organic matter content and thickness of leaf litter. The amount of variance of different centipede species distribution explained by environmental factors is relatively low which could indicate that our analysis lacks some environmental or other factors that would clearly describe centipede distribution within our study area. Another reason for our uncertian results is also a small sample size that was included in the analysis. Nevertheless, we can highlight that in the case of our study, field collected data proved to be more accurate for developing such models. One of the reasons for this could be the spatial scale in which publicly avalible environmetal data is collected. Such data is meant to be used for analisys made in the same spatial scale as the data was collected in, which is not the case in our study. Our results also suggest that environmental factors which potentially influence the centipede presence and distribution are species specific.
Secondary keywords: RDA;public access data;multivariate methods;species distiburion models;
Type (COBISS): Master's thesis/paper
Study programme: 0
Embargo end date (OpenAIRE): 1970-01-01
Thesis comment: Univ. Ljubljana, Biotehniška fak.
Pages: X f., 72, [14] str.
ID: 11230370