Latitudinal shifts in species interactions interfere with resistance of southern but not of northern bog‐plant communities to experimental climate change

• Published in: Journal of Ecology
• Main Authors: Schwarzer, Christian, Heinken, Thilo, Luthardt, Vera, Joshi, Jasmin
• Other Authors: Brooker, Rob
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2013
• Subjects: Subarctic
• Online Access: http://dx.doi.org/10.1111/1365-2745.12158; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2F1365-2745.12158; https://besjournals.onlinelibrary.wiley.com/doi/pdf/10.1111/1365-2745.12158

Summary The persistence of species under changed climatic conditions depends on adaptations and plastic responses to these conditions and on interactions with their local plant community resulting in direct and indirect effects of changed climatic conditions. Populations at species' range margins may be especially crucial in containing a gene pool comprising adaptations to extreme climatic conditions. Many species of northern E uropean bog ecosystems reach their southern lowland range limit in central E urope. In a common‐garden experiment, we experimentally assessed the impact of projected climatic changes on five bog‐plant species (including peat moss S phagnum magellanicum ) sampled along a latitudinal gradient of 1400 km from S candinavia to the marginal lowland populations in G ermany. Populations were cultivated in monocultures and in experimental communities composed of all five species from their local community, and exposed to five combinations of three climate treatments (warming, fluctuating water‐tables, fertilization) in a southern common garden. Whereas most monocultures showed a decreasing biomass production from southern to northern origins under southern environmental conditions, in the experimental mixed‐species communities, an increasing biomass production towards northern communities was observed together with a shift in interspecific interactions along the latitudinal gradient. While negative dominance effects prevailed in southern communities, higher net biodiversity effects were observed in northern subarctic communities. The combined effects of climate treatments increased biomass production in monocultures of most origins. In communities, however, overall the treatments did not result in significantly changed biomass production. Among individual treatments, water‐table fluctuations caused a significant decrease in biomass production, but only in southern communities, indicating higher vulnerability to changed climatic conditions. Here, negative effects of climate treatments on graminoids ...