Browsing NTNU Open by Author "Martinsen, Vegard"
Now showing items 1-7 of 7
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Carbon stocks across the Serengeti ecosystem: Impacts of climate, land-use and woody plant cover
Haukenes, Vilde Lytskjold (Master thesis, 2019)Vi står i dag ovenfor enorme utfordringer med tanke på økende arealbruks- og klimaendringer. Derfor er det vesentlig å forstå hvordan man mest effektivt forvalter et økosystem med økt karbonlagring i fokus. Et tiltak som ... -
Continuous and discontinuous variation in ecosystem carbon stocks with elevation across a treeline ecotone
Speed, James David Mervyn; Martinsen, Vegard; Hester, Alison J.; Holand, Øystein; Mulder, Jan; Mysterud, Atle; Austrheim, Gunnar (Journal article; Peer reviewed, 2015)Treelines differentiate vastly contrasting ecosystems: open tundra from closed forest. Treeline advance has implications for the climate system due to the impact of the transition from tundra to forest ecosystem on ... -
Effects of Sheep Grazing on Availability and Leaching of Soil Nitrogen in Low-Alpine Grasslands
Martinsen, Vegard; Mulder, Jan; Austrheim, Gunnar; Hessen, Dag Olav; Mysterud, Atle (Journal article; Peer reviewed, 2012)Alpine ecosystems are generally nitrogen (N) limited with low rates of N mineralization. Herbivory may affect N cycling and N losses and thus long-term productivity of ecosystems. Using a controlled grazing experiment in ... -
Experimental effects of herbivore density on above-ground plant biomass in an alpine grassland ecosystem
Austrheim, Gunnar; Speed, James David Mervyn; Martinsen, Vegard; Mulder, Jan; Mysterud, Atle (Journal article; Peer reviewed, 2014)Herbivores may increase or decrease aboveground plant productivity depending on factors such as herbivore density and habitat productivity. The grazing optimization hypothesis predicts a peak in plant production at ... -
Long-Term Increase in Aboveground Carbon Stocks Following Exclusion of Grazers and Forest Establishment in an Alpine Ecosystem
Speed, James David Mervyn; Martinsen, Vegard; Mysterud, Atle; Mulder, Jan; Holand, Øystein; Austrheim, Gunnar (Journal article; Peer reviewed, 2014)Ecosystem stores of carbon are a key component in the global carbon cycle. Many studies have examined the impact of climate change on ecosystem carbon storage, but few have investigated the impact of land-use change and ... -
Micromechanical Modelling of Strain Localization and Fracture in Aluminium
Martinsen, Vegard (Master thesis, 2012)Aluminium is often treated as a homogeneous material. However, when investigated on a microscopic scale, a granular structure is observed. The mechanical properties of the constituents, together with the distribution of ... -
Synergies and trade-offs between ecosystem services in analpine ecosystem grazed by sheep – An experimental approach
Austrheim, Gunnar; Speed, James David Mervyn; Evju, Marianne; Hester, Alison; Holand, Øystein; Loe, Leif Egil; Martinsen, Vegard; Mobæk, Ragnhild; Mulder, Jan; Steen, Harald; Thompson, Des B.A.; Mysterud, Atle (Journal article; Peer reviewed, 2016)Domestic livestock drives ecosystem changes in many of the world’s mountain regions, and can be the dominant influenceon soil, habitat and wildlife dynamics. Grazing impacts on ecosystem services (ES) vary according to ...