• 175 years of adaptation: North Scandinavian Sámi reindeer herding between government policies and winter climate variability (1835–2010) 

      Riseth, Jan Åge; Tømmervik, Hans; Bjerke, Jarle W. (Journal article; Peer reviewed, 2016)
      Unmanaged wild reindeer populations tend to follow cyclical behaviour, and domesticatedreindeer populations often show cyclical behaviour, too. In this contribution, we intendto use the long-term development of two areas ...
    • Alpine garden plants from six continents show high vulnerability to ice encasement 

      Bjerke, Jarle W.; Elvebakk, Arve; Tømmervik, Hans (Journal article; Peer reviewed, 2017)
      Icy surfaces impose challenges for northern societies, wildlife and agriculture. However, there have been relatively few studies of the impacts of anoxic ground ice on non-agricultural plants. During the winter of 2009–2010, ...
    • Arctic browning: extreme events and trends reversing arctic greening 

      Phoenix, G. K.; Bjerke, Jarle W. (Journal article; Peer reviewed, 2016)
    • Biologisk mangfold. Flakstad kommune 

      Strann, Karl Birger; Bjerke, Jarle W.; Frivoll, Vigdis Irene; Johnsen, Trond Vidar; Sortland, Frantz (NINA Rapport;139, Research report, 2006)
      Strann, K.-B., Bjerke, J.W., Frivoll, V., Johnsen, T.V. og Sortland, F. 2006. Biologisk mangfold: Flakstad kommune. - NINA Rapport 139. 35 s. Stortingsmelding nr. 42 (2000-2001) pålegger den enkelte sektor å gjennomføre ...
    • Biologisk mangfold. Karlsøy kommune 

      Strann, Karl Birger; Bjerke, Jarle W.; Frivoll, Vigdis Irene; Johnsen, Trond Vidar (NINA Rapport;208, Research report, 2007)
      Strann, K.-B., Bjerke, J. W., Frivoll, V. og Johnsen, T. V. 2007. Biologisk mangfold. Karlsøy kommune - NINA Rapport 208. 90s. Stortingsmelding nr. 42 (2000-2001) pålegger den enkelte sektor å gjennomføre kartlegging av ...
    • Biologisk mangfold. Røst kommune 

      Strann, Karl Birger; Bjerke, Jarle W.; Frivoll, Vigdis Irene; Johnsen, Trond Vidar (NINA Rapport;138, Research report, 2006)
      Strann, K.-B., Bjerke, J.W., Frivoll, V. og Johnsen, T.V. 2006. Biologisk mangfold: Røst kommune. - NINA Rapport 138. 42 s. Stortingsmelding nr. 42 (2000-2001) pålegger den enkelte sektor å gjennomføre kartlegging av ...
    • Biologisk mangfold. Skjervøy kommune 

      Strann, Karl Birger; Bjerke, Jarle W.; Frivoll, Vigdis Irene; Johnsen, Trond Vidar (NINA Rapport;209, Research report, 2007)
      Strann, K.-B., Bjerke, J.W., Frivoll, V. & Johnsen, T. V. 2007. Biologisk mangfold. Skjervøy kommune - NINA Rapport 209. 49 s. Stortingsmelding nr. 42 (2000-2001) pålegger den enkelte sektor å gjennomføre kartlegging av ...
    • Biologisk mangfold. Vestvågøy kommune 

      Strann, Karl Birger; Bjerke, Jarle W.; Frivoll, Vigdis Irene; Johnsen, Trond Vidar; Sortland, Frantz (NINA Rapport;140, Research report, 2006)
      Strann, K.-B., Bjerke, J. W., Frivoll, V., Johnsen, T.V. & Sortland, F. 2006. Biologisk mangfold. Vestvågøy kommune. - NINA Rapport 140. 80 pp. Stortingsmelding nr. 42 (2000-2001) pålegger den enkelte sektor å gjennomføre ...
    • Biologisk mangfold. Vågan kommune 

      Strann, Karl Birger; Bjerke, Jarle W.; Frivoll, Vigdis Irene; Johnsen, Trond Vidar; Sortland, Frantz (NINA Rapport;141, Research report, 2006)
      Strann, K.-B., Bjerke, J. W., Frivoll, V., Johnsen, T.V. & Sortland, F. 2006. Biologisk mangfold. Vågan kommune. - NINA Rapport 141. 56 pp. Stortingsmelding nr. 42 (2000-2001) pålegger den enkelte sektor å gjennomføre ...
    • Changes in winter warming events in the Nordic Arctic Region 

      Vikhamar-Schuler, Dagrun; Isaksen, Ketil; Haugen, Jan Erik; Tømmervik, Hans; Luks, Bartlomiej; Schuler, Thomas Vikhamar; Bjerke, Jarle W. (Journal article; Peer reviewed, 2016)
      In recent years extreme winter warming events have been reported in arctic areas. These events are characterized as extraordinarily warm weather episodes, occasionally combined with intense rainfall, causing ecological ...
    • Changing Arctic snow cover: A review of recent developments and assessment of future needs for observations, modelling, and impacts 

      Bokhorst, Stef; Pedersen, Stine Højlund; Brucker, Ludovic; Anisimov, Oleg; Bjerke, Jarle W.; Brown, Ross D.; Ehrich, Dorothee (Journal article, 2016)
      Snow is a critically important and rapidly changing feature of the Arctic. However, snow-cover and snowpack conditions change through time pose challenges for measuring and prediction of snow. Plausible scenarios of ...
    • Climatic and biotic extreme events moderate long-term responses of above- and belowground sub-Arctic heathland communities to climate change 

      Bokhorst, Stef; Phoenix, Gareth K.; Berg, Matty P.; Callaghan, Terry V.; Kirby-Lambert, Christopher; Bjerke, Jarle W. (Journal article; Peer reviewed, 2015)
      Climate change impacts are not uniform across the Arctic region because interacting factors causes large variations in local ecosystem change. Extreme climatic events and population cycles of herbivores occur simultaneously ...
    • Combining modelling tools to evaluate a goose management scheme 

      Baveco, Johannes M.; Bergjord, Anne-Kari; Bjerke, Jarle W.; Chudzinska, Magda E.; Pellissier, Loïc; Simonsen, Caroline E.; Madsen, Jesper; Tombre, Ingunn; Nolet, Bart A. (Journal article; Peer reviewed, 2017)
      Many goose species feed on agricultural land, and with growing goose numbers, conflicts with agriculture are increasing. One possible solution is to designate refuge areas where farmers are paid to leave geese undisturbed. ...
    • Contrasting survival and physiological responses of sub-Arctic plant types to extreme winter warming and nitrogen 

      Bokhorst, Stef; Jaakola, Laura; Karppinen, Katja; Edvinsen, Guro Kristine; Mæhre, Hanne Kirsti; Bjerke, Jarle W. (Journal article; Peer reviewed, 2017)
      Main conclusion Evergreen plants are more vulnerable than grasses and birch to snow and temperature variability in the sub-Arctic. Most Arctic climate impact studies focus on single factors, such as summer warming, while ...
    • Feasibility of hyperspectral vegetation indices for the detection of chlorophyll concentration in three high Arctic plants: Salix polaris, Bistorta vivipara, and Dryas octopetala 

      Zagajewski, Bogdan; Kycko, Marlena; Tømmervik, Hans; Bochenek, Zbigniew; Wojtun, Bronislaw; Bjerke, Jarle W.; Klos, Andrzej (Peer reviewed, 2018)
      Remote sensing, which is based on a reflected electromagnetic spectrum, offers a wide range of research methods. It allows for the identification of plant properties, e.g., chlorophyll, but a registered signal not only ...
    • Fremmede karplanter i Norge: modellering av introduksjonsområder og nåværende utbredelse 

      Olsen, Siri Lie; Åström, Jens; Hendrichsen, Ditte; Bjerke, Jarle W.; Blaalid, Rakel; Töpper, Joachim; Bakkestuen, Vegar (NINA Rapport;1393, Research report, 2017)
      Olsen, S.L., Åström, J., Hendrichsen, D., Bjerke, J. W., Blaalid, R., Töpper, J. & Bakkestuen, V. 2017. Fremmede karplanter i Norge: modellering av introduksjonsområder og nåværende utbredelse. – NINA Rapport 1393. 116 ...
    • Gjess i Nord-Trøndelag. Status september 2017 

      Tombre, Ingunn M.; Bjerke, Jarle W.; Brattland, Camilla; Eythórsson, Einar; Fredriksen, Fredrik; Gundersen, Ove Martin; Holmgaard, Sanne Bech; Olsen, Anne Kari Bergjord; Reinsborg, Tore (NINA Rapport;1390, Research report, 2017)
      Tombre, I.M., Bjerke, J. W., Brattland, C., Eythórsson, E., Fredriksen, F., Gundersen, O.M, Holmgaard, S.B., Olsen, A. K. B. & Reinsborg, T. 2017. Gjess i Nord-Trøndelag. Status september 2017. - NINA Rapport 1390, 22 ...
    • High tolerance of a high-arctic willow and graminoid to simulated ice encasement 

      Bjerke, Jarle W.; Elverland, Ellen; Jaakola, Laura; Lund, Leidulf; Zagajewski, Bogdan; Bochenek, Zbigniew; Kłos, Andrzej; Tømmervik, Hans (Journal article; Peer reviewed, 2018)
      Climate change-induced snow thaw and subsequent accumulation of ice on the ground is a potential, major threat to snow-dominated ecosystems. While impacts of ground-ice on arctic wildlife are well explored, the impacts on ...
    • Høymyrer i Andøy kommune – Kartlegging av forekomster primært på grunnlag av flybildeserier 

      Bjerke, Jarle W. (NINA Rapport;82, Research report, 2005)
      Bjerke, J. W. 2005: Høymyrer i Andøy kommune – Kartlegging av forekomster primært på grunnlag av flybildeserier - NINA Rapport 82. 22 s. På oppdrag for Andmyran Vindpark AS har NINA foretatt en undersøkelse av forekomster ...
    • Impact of Multiple Ecological Stressors on a Sub-Arctic Ecosystem: No Interaction Between Extreme Winter Warming Events, Nitrogen Addition and Grazing 

      Bokhorst, Stef; Berg, atty P.; Edvinsen, Guri K.; Ellers, Jacintha; Heitman, Amber; Jaakola, Laura; Mæhre, Hanne K.; Phoenix, Gareth K.; Tømmervik, Hans; Bjerke, Jarle W. (Peer reviewed, 2018)
      Climate change is one of many ongoing human-induced environmental changes, but few studies consider interactive effects between multiple anthropogenic disturbances. In coastal sub-arctic heathland, we quantified the ...