The effect of long-term temperature enhancement on the subarctic-alpine biocomplexity

• Climate change is expected to alter the nitrogen availability and soil carbon dynamics and, as a consequence, affect plant community composition and production and thereby ecosystem gas flux rates. The International Tundra Experiment (ITEX) was established at Latnjajaure Field Station (LFS), in northern Swedish Lapland, in 1993 and gives a great opportunity to investigate the long-term effect of climatic warming on the soil ecosystem. The Open Top Chambers (OTCs) used within ITEX are located in five different plant communities, which covers both heaths and meadows and the gradient from dry to moist plant communities. The ITEX species Cassiope tetragona, Dryas octopetala, Eriophorum vaginatum, Polygonum viviparum and Ranunculus nivalis, studied at LFS, are all showing positive responses to phenology, growth and reproduction to the warming treatment. The temperature enhancement on the plant community level seems to lead to changes in the dominance of species, especially by shrubs and bryophytes. However, the overall plant community pattern also appears to depend much on changes in the nitrogen availability, where their combined effects are multiplicative rather than additive with a rapidly decrease in species diversity. In this newly started study we are adopting the results from the ITEX study and try to relate them to the soil processes and properties such as potential nitrification and denitrification, soil organic matter, C:N ratio and ecosystem respiration. Thus, we make an effort to amalgamate plant community changes with changes in the subarctic-alpine soil ecosystem.

Subject headings

NATURVETENSKAP  -- Biologi -- Ekologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Ecology (hsv//eng)

Keyword

Arctic

Climate Change

ITEX

Publication and Content Type

vet (subject category)

kon (subject category)