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[{"key": "dc.contributor.advisor", "value": "Karjalainen, Juha", "language": "", "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.advisor", "value": "Marjom\u00e4ki, Timo", "language": "", "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.author", "value": "Borg, Venla", "language": "", "element": "contributor", "qualifier": "author", "schema": "dc"}, {"key": "dc.date.accessioned", "value": "2024-12-09T06:40:27Z", "language": null, "element": "date", "qualifier": "accessioned", "schema": "dc"}, {"key": "dc.date.available", "value": "2024-12-09T06:40:27Z", "language": null, "element": "date", "qualifier": "available", "schema": "dc"}, {"key": "dc.date.issued", "value": "2024", "language": "", "element": "date", "qualifier": "issued", "schema": "dc"}, {"key": "dc.identifier.uri", "value": "https://jyx.jyu.fi/handle/123456789/98853", "language": null, "element": "identifier", "qualifier": "uri", "schema": "dc"}, {"key": "dc.description.abstract", "value": "Kalojen elinkierron tuntemus on oleellista kalakantojen kest\u00e4v\u00e4n kalastuksen ja\nsuojelun kannalta. Muikku (Coregonus albula) on Suomessa merkitt\u00e4v\u00e4\nkaupallisen sis\u00e4vesikalastuksen kohdelaji. Muikun t\u00e4rke\u00e4st\u00e4 asemasta\nhuolimatta etenkin sen elinkierron varhaisiin vaiheisiin liittyy viel\u00e4 avoimia\nkysymyksi\u00e4. T\u00e4ss\u00e4 tutkimuksessa oli tarkoitus arvioida m\u00e4timunien ja poikasten\ntiheyksi\u00e4 ja levinneisyytt\u00e4 osana muikun lis\u00e4\u00e4ntymisstrategiaa S\u00e4kyl\u00e4n\nPyh\u00e4j\u00e4rvess\u00e4. Lis\u00e4ksi tavoitteena oli selvitt\u00e4\u00e4 kutukannan koko. M\u00e4titiheyksi\u00e4\ntutkittiin Pyh\u00e4j\u00e4rvess\u00e4 ensimm\u00e4ist\u00e4 kertaa uudenlaisella passiivisella\nm\u00e4tiker\u00e4inmenetelm\u00e4ll\u00e4. Syksyll\u00e4 2022 150 m\u00e4tiker\u00e4int\u00e4 laskettiin 10 paikkaan\nnelj\u00e4\u00e4n syvyysvy\u00f6hykkeeseen 0\u201312 m v\u00e4lille ja syksyll\u00e4 2023 12 paikkaan\nkolmeen syvyysvy\u00f6hykkeeseen 0\u20139 m v\u00e4lille. M\u00e4timunia l\u00f6ytyi molempina\nvuosina kaikista n\u00e4ytepaikoista, mutta vain alle 6 m syvyydest\u00e4. M\u00e4timunien\ntiheyksiss\u00e4 ei havaittu merkitsevi\u00e4 eroja paikkojen v\u00e4lill\u00e4, eik\u00e4\nsyvyysvy\u00f6hykkeell\u00e4 (0\u20133 m ja 3\u20136 m) havaittu olevan merkitsev\u00e4\u00e4 vaikutusta\nm\u00e4titiheyteen vuonna 2022. Vuonna 2023 puolestaan 0\u20133 m syvyydess\u00e4 oli\nkeskim\u00e4\u00e4rin enemm\u00e4n m\u00e4timunia 3\u20136 m verrattuna. Munien keskitiheysarvio oli\nkoko j\u00e4rvess\u00e4 220 000 kpl ha-1 vuonna 2022 ja 120 000 kpl ha-1 vuonna 2023.\nPoikastiheyksi\u00e4 tutkittiin standardoidulla menetelm\u00e4ll\u00e4 kev\u00e4\u00e4ll\u00e4 2023 ja 2024.\nMolempina vuosina poikasia havaittiin ymp\u00e4ri j\u00e4rve\u00e4. Poikastiheydet olivat\nmerkitsev\u00e4sti suuremmat kev\u00e4\u00e4ll\u00e4 2023 kev\u00e4\u00e4seen 2024 verrattuna. M\u00e4timunien\nja poikasten paikkakohtaisten tiheyksien v\u00e4lill\u00e4 ei havaittu merkitsev\u00e4\u00e4\nkorrelaatiota. Kutukannan tiheysarvio naaraat ja koiraat yhteen laskien oli\nPyh\u00e4j\u00e4rvess\u00e4 2,1 kg ha-1 syksyll\u00e4 2022 ja 0,7 kg ha-1 syksyll\u00e4 2023.\nM\u00e4tiker\u00e4inmenetelm\u00e4 toimi odotusten mukaisesti ja tuotti suhteellisen\nluotettavia tuloksia. T\u00e4m\u00e4n tutkimuksen tulokset vahvistavat k\u00e4sityst\u00e4 siit\u00e4, ett\u00e4\nmuikun lis\u00e4\u00e4ntymiselle on luontaista m\u00e4timunien levitt\u00e4minen laajasti ymp\u00e4ri\nj\u00e4rve\u00e4 antaen munille ja kuoriutuville poikasille paremmat mahdollisuudet\nselviyty\u00e4 vaihtelevissa ymp\u00e4rist\u00f6olosuhteissa.", "language": "fi", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.abstract", "value": "Detailed knowledge about life history of fishes is crucial for sustainable fisheries\nand conservation of fish stocks. Vendace (Coregonus albula) is an important target\nspecies in Finnish inland fisheries. There are still many open questions about the\nearly life stages of vendace. The aim of this study was to estimate egg and larval\ndensities and dispersal as a part of the reproductive strategy of vendace. The aim\nwas also to estimate the size of the spawning stock. Egg densities were studied\nfor the first time with passive egg samplers in lake S\u00e4kyl\u00e4n Pyh\u00e4j\u00e4rvi. In autumn\n2022, 150 egg samplers were set in 10 study sites in four different depth zones\nbetween 0\u201312 m and in autumn 2023, in 12 study sites in three depth zones\nbetween 0\u20139 m. Vendace eggs were found in all sites in both years, but only in\ndepths less than 6 m. Depth zone (0\u20133 m and 3\u20136 m) had no significant effect on\negg densities in 2022, whereas in 2023, egg densities were higher on average in\ndepth zone 0\u20133 m compared to 3\u20136 m. There were no significant differences in\negg densities between sites. The mean egg density of the lake was 220 000 eggs\nha-1 in 2022 and 120 000 eggs ha-1 in 2023. Larval densities were studied in the\nspring of 2023 and spring 2024 with a standardized method. In both years,\nvendace larvae were dispersed throughout the lake. Larval densities were higher\nin 2023 than in 2024. There was no correlation between site specific egg and larval\ndensities. The spawning stock biomass (including both females and males) was\nestimated 2,1 kg ha-1 in 2022 and 0,7 kg ha-1 in 2023. The method used for egg\ndensity estimation worked successfully and provided relatively reliable results.\nThe results of this study support the understanding that vendace disperse their\neggs throughout the lake, thus providing eggs and larvae a better chance of\nsurvival in varying environmental conditions.", "language": "en", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Submitted by Paivi Vuorio (paelvuor@jyu.fi) on 2024-12-09T06:40:27Z\nNo. of bitstreams: 0", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Made available in DSpace on 2024-12-09T06:40:27Z (GMT). No. of bitstreams: 0\n Previous issue date: 2024", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.format.extent", "value": "36", "language": "", "element": "format", "qualifier": "extent", "schema": "dc"}, {"key": "dc.language.iso", "value": "fin", "language": null, "element": "language", "qualifier": "iso", "schema": "dc"}, {"key": "dc.rights", "value": "In Copyright", "language": "en", "element": "rights", "qualifier": null, "schema": "dc"}, {"key": "dc.subject.other", "value": "fekunditeetti", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "kutukanta-arvio", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "kutuk\u00e4ytt\u00e4ytyminen", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "levitt\u00e4ytyminen", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "talvikuolleisuus", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.title", "value": "Muikun (Corgonus albula) m\u00e4ti- ja poikastiheyden sek\u00e4 kutukannan arviointi S\u00e4kyl\u00e4n Pyh\u00e4j\u00e4rvess\u00e4", "language": "", "element": "title", "qualifier": null, "schema": "dc"}, {"key": "dc.type", "value": "master thesis", "language": null, "element": "type", "qualifier": null, "schema": "dc"}, {"key": "dc.identifier.urn", "value": "URN:NBN:fi:jyu-202412097667", "language": null, "element": "identifier", "qualifier": "urn", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Master\u2019s thesis", "language": "en", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Pro gradu -tutkielma", "language": "fi", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Matemaattis-luonnontieteellinen tiedekunta", "language": "fi", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Faculty of Sciences", "language": "en", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Bio- ja ymp\u00e4rist\u00f6tieteiden laitos", "language": "fi", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Department of Biological and Environmental Science", "language": "en", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "Jyv\u00e4skyl\u00e4n yliopisto", "language": "fi", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "University of Jyv\u00e4skyl\u00e4", "language": "en", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Akvaattiset tieteet", "language": "fi", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Aquatic sciences", "language": "en", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "yvv.contractresearch.funding", "value": "0", "language": "", "element": "contractresearch", "qualifier": "funding", "schema": "yvv"}, {"key": "dc.type.coar", "value": "http://purl.org/coar/resource_type/c_bdcc", "language": null, "element": "type", "qualifier": "coar", "schema": "dc"}, {"key": "dc.rights.accesslevel", "value": "restrictedAccess", "language": null, "element": "rights", "qualifier": "accesslevel", "schema": "dc"}, {"key": "dc.type.publication", "value": "masterThesis", "language": null, "element": "type", "qualifier": "publication", "schema": "dc"}, {"key": "dc.subject.oppiainekoodi", "value": "4012", "language": "", "element": "subject", "qualifier": "oppiainekoodi", "schema": "dc"}, {"key": "dc.subject.yso", "value": "muikku", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "j\u00e4rvet", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "kalakannat", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "lis\u00e4\u00e4ntyminen", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "kalat", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "tiheys", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.rights.url", "value": "https://rightsstatements.org/page/InC/1.0/", "language": null, "element": "rights", "qualifier": "url", "schema": "dc"}, {"key": "dc.rights.accessrights", "value": "The author has not given permission to make the work publicly available electronically. Therefore the material can be read only at the archival workstation at Jyv\u00e4skyl\u00e4 University Library (https://kirjasto.jyu.fi/collections/archival-workstation).", "language": "en", "element": "rights", "qualifier": "accessrights", "schema": "dc"}, {"key": "dc.rights.accessrights", "value": "Tekij\u00e4 ei ole antanut lupaa avoimeen julkaisuun, joten aineisto on luettavissa vain Jyv\u00e4skyl\u00e4n yliopiston kirjaston arkistoty\u00f6semalta. Ks. https://kirjasto.jyu.fi/kokoelmat/arkistotyoasema..", "language": "fi", "element": "rights", "qualifier": "accessrights", "schema": "dc"}]
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