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dc.date.accessioned2013-03-12T08:44:28Z
dc.date.available2013-03-12T08:44:28Z
dc.date.issued2010en_US
dc.date.submitted2010-12-01en_US
dc.identifier.citationMagnussen, Tore. Aerial dispersal of invertebrates on Svalbard and the influence of weather. Masteroppgave, University of Oslo, 2010en_US
dc.identifier.urihttp://hdl.handle.net/10852/11717
dc.description.abstractA total of 20 water traps were set out at four locations around Longyearbyen on the High Arctic island Spitsbergen. The traps sampled aerially dispersed invertebrates during the summer of 2008. These trapping locations were in relatively close proximity to weather stations that recorded the local variations in weather. During the summer, the traps caught 102 Acari, 47 Collembola, 8 Aphidoideae and 5 Araneae as well as 10979 Nematocera, 177 Brachycera and 36 Hymenoptera. The effect of weather on aerial dispersal rates of invertebrates was studied and three general hypotheses were tested, that (1) aerial dispersal rates of wingless invertebrates will increase with wind speed, (2) aerial dispersal rates for all invertebrates will increase with temperature, (3) Collembola aerial dispersal will increase with relative humidity. To study the relationship between invertebrate catches and weather variables, canonical correspondence analysis, multiple regression and linear regression methods were used. Based on our results, we conclude that relative humidity has a positive effect on Collembola dispersal rates and the related hypothesis is accepted. The effect of wind speed on Collembola dispersal is negative and this is thought to be because of a negative relationship between wind speed and relative humidity. The hypothesis that increased wind speed has a positive effect on Collembola aerial dispersal is rejected. Brachycera and Hymenoptera respond positively to temperature and the related hypothesis is accepted. The explanation is thought to be the presence of temperature threshold values under which winged insects are not able to take flight. On average, warmer temperatures mean winged insects are able to spend more time flying. Wind speed has a negative relationship with Brachycera and Hymenoptera dispersal and this is thought to be because of an avoidance strategy where Brachycera and Hymenoptera avoid taking to the air or fly at lower altitude as flying into winds represents a risk of being swept away from a preferred habitat. Analysis did not find any significant relationships between Acari aerial dispersal and weather and due to errors in the study related to site location and hidden variables, no conclusions are drawn regarding Nematocera dispersal and how it is affected by weather. Catch densities of Aphidoideae and Araneae were considered too low for statistical testing.eng
dc.language.isoengen_US
dc.titleAerial dispersal of invertebrates on Svalbard and the influence of weatheren_US
dc.typeMaster thesisen_US
dc.date.updated2011-03-09en_US
dc.creator.authorMagnussen, Toreen_US
dc.subject.nsiVDP::488en_US
dc.identifier.bibliographiccitationinfo:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Magnussen, Tore&rft.title=Aerial dispersal of invertebrates on Svalbard and the influence of weather&rft.inst=University of Oslo&rft.date=2010&rft.degree=Masteroppgaveen_US
dc.identifier.urnURN:NBN:no-26788en_US
dc.type.documentMasteroppgaveen_US
dc.identifier.duo109247en_US
dc.contributor.supervisorVladimir Gusarov, María Luisa Ávila Jiménez, Stephen J. Coulsonen_US
dc.identifier.bibsys111971586en_US
dc.identifier.fulltextFulltext https://www.duo.uio.no/bitstream/handle/10852/11717/2/TORExMAGNUSSEN_MASTER.pdf


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