Species turnover reveals hidden effects of decreasing nitrogen deposition in mountain hay meadows

Zoological Institute, University of Basel, Basel, Switzerland
Hintermann & Weber AG, Reinach, Switzerland
Meteotest, Bern, Switzerland
Swiss Soil Monitoring Network NABO, Agroscope, Zurich, Switzerland
Air Pollution Control and Chemicals Division, Federal Office for the Environment (FOEN), Bern, Switzerland
DOI
10.7287/peerj.preprints.27230v2
Subject Areas
Biodiversity, Ecology, Plant Science, Climate Change Biology, Environmental Impacts
Keywords
alpine meadows, nitrogen critical loads, plant community composition, species richness, grassland, biodiversity, Biodiversity monitoring, mountain hay meadows, Nitrogen deposition
Copyright
© 2018 Roth et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Roth T, Kohli L, Bühler C, Rihm B, Meuli RG, Meier R, Amrhein V. 2018. Species turnover reveals hidden effects of decreasing nitrogen deposition in mountain hay meadows. PeerJ Preprints 6:e27230v2

Abstract

Nitrogen (N) deposition is a major threat to biodiversity in many habitats. The recent introduction of cleaner technologies in Switzerland has led to a reduction in the emissions of nitrogen oxides, with a consequent decrease in N deposition. We examined different drivers of plant community change, i.e. N deposition, climate warming, and land-use change, in Swiss mountain hay meadows, using data from the Swiss biodiversity monitoring program. We compared indicator values of species that disappeared from or colonized a site (species turnover) with the indicator values of randomly chosen species from the same site. While oligotrophic plant species were more likely to colonize, compared to random expectation, we found only weak shifts in plant community composition. In particular, the average nutrient value of plant communities remained stable over time (2003-2017). We found the largest deviations from random expectation in the nutrient values of colonizing species, suggesting that N deposition or other factors that change the nutrient content of soils were important drivers of the species composition change over the last 15 years in Swiss mountain hay meadows. In addition, we observed an overall replacement of species with lower indicator values for temperature with species with higher values. Apparently, the community effects of the replacement of eutrophic species with oligotrophic species was outweighed by climate warming. Our results add to the increasing evidence that plant communities in changing environments may be relatively stable regarding average species richness or average indicator values, but that this apparent stability is often accompanied by a marked turnover of species.

Author Comment

This version includes changes in response to the comments by two reviewers ("minor revision").

Supplemental Information

Appendix A: Comparision of lost/gained species to randomly selected species Appendix A: Comparision of lost/gained species to randomly selected species

Appendix A: Comparision of lost/gained species to randomly selected species

DOI: 10.7287/peerj.preprints.27230v2/supp-1