Winter climate change is affecting the carbon exchange of northern coniferous forests, but the response depends upon reindeer grazing, according to a new study from the University of Oulu.
Winter climate change is affecting the carbon exchange of northern coniferous forests, but the response depends upon reindeer grazing, according to a new study from the University of Oulu. The study compared areas with ongoing reindeer grazing to areas where grazing has been excluded for 25 years at Oulanka and as long as 55 years at Kevo.
Northern forests store one third of the global carbon and act as sinks for atmospheric carbon dioxide. In addition to trees, understory vegetation and soil play a significant role in regulating carbon sinks. Climate change-induced alterations in snow depth and duration affect the carbon cycle not only in winter but also during the following growing season in summer. At the same time, reindeer grazing affects the carbon cycle, for example, by reducing the abundance of lichens in the understory.
Researchers at the University of Oulu have measured the impacts of snow cover and reindeer grazing on the carbon cycle in northern Finland’s coniferous forests during the growing seasons of 2019–2023. The experiments included areas with ongoing reindeer grazing as well as in areas where grazing has been excluded for 25 years at Oulanka in eastern Finland and for 55 years at Kevo in northernmost Finland. In addition, snow experiments of increased and decreased snow depth were carried out at each of these areas.
Read More: University of Oulu, Finland
Image: The new study from the University of Oulu provides, for the first time, evidence of the role of reindeer grazing in shaping winter climate change impacts on the carbon cycle. Image Noora Kantola / the University of Oulu (Photo Credit: Noora Kantola / University of Oulu)
