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Jukuri

Tervetuloa käyttämään Jukuria, Luonnonvarakeskuksen (Luke) avointa julkaisuarkistoa. Jukurissa on tiedot Luken julkaisutuotannosta. Osa julkaisuista on vapaasti ladattavissa. Luken muodostaneiden tutkimuslaitosten aikaisemmasta julkaisutuotannosta osan tiedot ovat järjestelmässä jo nyt ja kattavuus paranee jatkuvasti.

Kokoelmat

Viimeksi tallennetut

  • Puna-apilan siemenviljely: Pölyttäjiä suosiva maisema
    Nykänen, Inka; Tolonen, Saara; Kykkänen, Sanna
    Luke tietokortti (Luonnonvarakeskus, 2026)
    Puna-apilan tehokkaimpia pölyttäjiä ovat pitkäkieliset kimalaiset. Ne ovat etenkin avoimien ja puoliavoimien elinympäristöjen lajeja, jotka ovat erikoistuneet hyödyntämään pitkätorvisten kukkien (esim. apilat, virnat) mettä. Puna-apilalohkon tulisi kuulua isompaan peltoalueeseen, jolta löytyy myös viljelemättömiä avoimia ja puoliavoimia alueita. Kukkajatkumon toteutuminen on tärkeää ja mesikasvien tulisi löytyä avoimilta tai puoliavoimilta alueilta. Viljelemättömien avoimien ja puoliavoimien ympäristöjen määrän lisäksi niiden hyvä laatu on tärkeää pitkäkielisille kimalaisille.
  • Impact of Environmental Conditions on the Spawning Migration of Sea Trout (Salmo trutta L.) in Two Large, Sub‐Arctic River Systems
    Lähteenmäki, L.; Romakkaniemi, Atso; Huusko, Riina; Hellström, G.; Orell, Panu; Erkinaro, Jaakko; Rikardsen, A. H.; Jensen, J.; Snickars, M.
    Fisheries management and ecology (Wiley-Blackwell, 2026)
    The global decline in salmonid stocks has increased the need for knowledge of local adaptations and life history strategies of salmonids. In this study, we used radio-telemetry tracking data from sea trout populations in two large high-latitude rivers to model upstream spawning migration speed of trout in response to prevailing environmental conditions and different stages of the migration. The results indicate that studied populations had similar responses to environmental changes, as trout inhabiting both rivers displayed similar responses to variation in discharge, temperature, and migrated distance covered. Higher discharge and temperature had a positive influence on trout migration speed, as did moderate discharge fluctuations. Migration distance influenced movements, as speed increased as trout moved upstream, while speed decreased late in the migration prior to spawning. These results highlight the adaptability of sea trout populations, underlining the importance of stock-specific information on habitat use and migration strategies for targeted management.
  • Rapid increase in abundance and distribution of invasive pink salmon (Oncorhynchus gorbuscha) within a diverse, large Barents Sea catchment
    Erkinaro, Jaakko; Orell, Panu; Fossøy, Frode; Kytökorpi, Mikko; Gjelland, Karl; Johansen, Narve; Domaas, Sigurd; Kuusela, Jorma; Fagard, Pierre; Frøiland, Eirik; Falkegård, Morten
    Journal of fish biology (John Wiley & Sons, 2026)
    Pink salmon originate from the North Pacific area but were introduced into northwest Russia from the late 1950s onwards. Since 2017, the alien species has increased dramatically in abundance and rapidly invaded adjacent areas of the North Atlantic region. In the large Teno River in northernmost Norway and Finland, running to the Barents Sea, various monitoring methods originally designed for assessment of Atlantic salmon populations have been used to observe the development in abundance and distribution of pink salmon in the main stem and in a number of tributaries. In addition, environmental DNA (eDNA) sampling has enabled monitoring of these trends across an even wider set of tributaries. The first observations of pink salmon were made in the 1960s, and variable but mostly low catches were recorded in the following decades. In recent years, the total number of pink salmon entering the Teno system increased rapidly from c. 5000 in 2017 to c. 180,000 in 2023. Initially, the invading pink salmon were occupying the main stem, large tributaries and headwater rivers of the catchment, even up to a distance of 250–350 km from the sea. However, in recent years, a greater number of smaller tributaries have been occupied as demonstrated by eDNA detections and other observations. The largest spawning aggregations of pink salmon have been observed in the main stem of the Teno River. Future development in the abundance and dispersal of pink salmon in the Teno system depends strongly on the extent and success of the mitigation efforts in intercepting and removing pink salmon by a weir and trap close to the estuary.
  • 21st century Northern Hemisphere warming in a 2025-year context of climatic events using tree-ring data
    Helama, Samuli
    Discover geoscience : 1 (Springer Nature, 2026)
    In this study, previously built community ensemble reconstruction, fully based on tree-ring proxy data, is used as a precisely estimated preindustrial-to-present-day temperature scale for Northern Hemisphere summer (June through August) variability over the past two thousand years, against which the recent variability in the observed record was evaluated. The proxy data verified successfully against temperature variability defined by grid boxes extending the tree-ring sites by plus/minus 10 degrees latitudinally and longitudinally (but not over wider spatial scales) over the 1921–2010 period. Summer 2024 was the warmest in the instrumental record, 2.8 °C above the preindustrial 1850–1900 reconstruction mean. In comparison, the warmest and coldest reconstructed summers in AD 246 and AD 536 were, respectively, 1.5 °C and 5.5 °C colder than the 2024 warmth. This means that the full range of natural climate variability was 4.0 °C, which was increased to 5.5 °C by 21st century warming. Temporal pattern of the warmest and coldest preindustrial 1-year temperature events reflected the long-term climatic swings previously described in paleoclimate literature through the Roman Warm Period, AD 536/540s event, Mediaeval Warm Period and Little Ice Age. Despite the improvements in the data processing, the reconstruction still contains considerable uncertainties. A future aim should be to develop denser tree-ring networks to fully cover the extra-tropical Northern Hemisphere land temperature grid boxes for an improved evaluation of the preindustrial and 21st century climatic events, for which purpose the Roman Warm Period appears an interesting, yet largely unexplored, climatic feature.
  • Occurrence of Twins in Saimaa Ringed Seals
    Alakoski, Riikka; Mutka, Piia; Auttila, Miina; Niemi, Marja; Kunnasranta, Mervi
    Marine mammal science : 2 (Wiley-Blackwell, 2026)