Sub-arctic plant community structure and invasibility.
Scientists involved: apl. Prof. Dr. Rolf Lutz Eckstein, Dr. Bente Graae (Trondheim University, Norway), Dr. Ann Milbau (Umeå University, Sweden)
Project period: 2008 -
Keywords: Community invasibility; Community structure; Climate change; Germination; Litter; Seedling establishment; Sub-arctic heath.
Recent climate change has left its mark on numerous natural processes (Walther et al. 2002, Nature 416: 389-395; Walker et al. 2006, PNAS 103: 1342-1346). Increasing temperatures have changed species phenologies with important implications for complex direct and indirect interactions, and there is evidence for current range dynamics of plants as a response to warming (Walther et al. 2002; 2005, P Roy Soc B-Biol Sci 272: 1427-1432). Results of the International Tundra Experiment (ITEX) concerning the effects of temperature elevation on community structure suggest that (1) plant productivity will increase, (2) the cover of dead plant remains (i.e. litter), and the cover of shrubs and grasses will increase, whereas (3) the cover of bryophytes will decrease in Arctic areas (Walker et al. 2006).
The anticipated changes in community composition and species distributions as a consequence of climate change depend on the invasibility of plant communities. Invasibility is related to vegetation structure, but the importance of the different components of vegetation structure are largely unknown. In the light of climate-induced changes of these components, studies addressing their impact on community invasibility become particularly important for realistic modelling of rates of changes in community compositon and species distributions.
Thus the aim of the study is to disentangle the effects of different components of vegetation structure (living plants, bryophytes, litter) on seedling establishment along an altitudinal gradient.
Funding: EU ATANS grant (FP6 506004)
Eckstein, R.L., Pereira, E., Milbau, A. & Graae, B.J. 2011. Predicted changes in vegetation structure affect the susceptibility to invasion of bryophyte dominated subarctic heath.- Annals of Botany 108: 177-183.