Abstract
Climate warming causes upward shifts of plant species distributions, resulting in an influx of species from lower elevations into alpine plant communities. Plant functional trait changes along elevation gradients and over time may reflect these changing conditions. Intraspecific trait variation measured from herbarium records offer a way to observe such changes in trait values over time.
We selected four species: Poa alpina and Polygonum viviparum found in alpine grasslands, and Cardamine resedifolia and Ranunculus glacialis found in high-alpine to subnival scree habitats. We measured several functional traits from (i) herbarium records collected between 1880-1950 and from (ii) individuals resampled in 2014 along an elevation gradient covering 13 >1500 m within the same study region in the Swiss Alps. By comparing (i) against (ii) for each
14 species separately, we analysed temporal changes in the distribution of traits along the studied elevation gradient.
After a century of climate warming, the change in the relationship linking plant functional traits with elevation was species dependent. Size-related and reproductive functional trait values for P. viviparum increased over time, increasing at lower, but not higher elevations. P. alpina’s size-related traits increased consistently with time along the elevation gradient. Most of C.
resedifolia’s size-related and flowering traits decreased over time at lower elevations, and converged at higher elevations. Finally, R. glacialis traits did not respond to time alone -reproductive traits decreased over time at lower, and increased at higher elevations, reversing their historical trait distributions. The negative trend for vegetative trait values with elevation did not change over time, however. In 2014, at lower elevations, all species mainly occurred on their typical microhabitat types, but osccurrence on other microhabitats increased with
elevation for all species.
Synthesis. Contrasting temporal changes in the distribution of growth and reproductive trait values between alpine grassland and alpine-subnival scree species, especially at lower elevations, suggest that climate warming effects vary among species. Additionally, species’ physiological constraints and availability of suitable microhabitats may further impact species’ distribution changes. Further warming may confine the distribution of high-alpine plant species to even higher elevations, or to microclimates currently difficult to colonise by lower-alpine species.
We selected four species: Poa alpina and Polygonum viviparum found in alpine grasslands, and Cardamine resedifolia and Ranunculus glacialis found in high-alpine to subnival scree habitats. We measured several functional traits from (i) herbarium records collected between 1880-1950 and from (ii) individuals resampled in 2014 along an elevation gradient covering 13 >1500 m within the same study region in the Swiss Alps. By comparing (i) against (ii) for each
14 species separately, we analysed temporal changes in the distribution of traits along the studied elevation gradient.
After a century of climate warming, the change in the relationship linking plant functional traits with elevation was species dependent. Size-related and reproductive functional trait values for P. viviparum increased over time, increasing at lower, but not higher elevations. P. alpina’s size-related traits increased consistently with time along the elevation gradient. Most of C.
resedifolia’s size-related and flowering traits decreased over time at lower elevations, and converged at higher elevations. Finally, R. glacialis traits did not respond to time alone -reproductive traits decreased over time at lower, and increased at higher elevations, reversing their historical trait distributions. The negative trend for vegetative trait values with elevation did not change over time, however. In 2014, at lower elevations, all species mainly occurred on their typical microhabitat types, but osccurrence on other microhabitats increased with
elevation for all species.
Synthesis. Contrasting temporal changes in the distribution of growth and reproductive trait values between alpine grassland and alpine-subnival scree species, especially at lower elevations, suggest that climate warming effects vary among species. Additionally, species’ physiological constraints and availability of suitable microhabitats may further impact species’ distribution changes. Further warming may confine the distribution of high-alpine plant species to even higher elevations, or to microclimates currently difficult to colonise by lower-alpine species.
| Original language | English |
|---|---|
| Number of pages | 18 |
| Journal | Journal of Ecology |
| Early online date | 24 Jan 2023 |
| DOIs | |
| Publication status | E-pub ahead of print - 24 Jan 2023 |
Bibliographical note
AcknowledgementsThis project would not have been possible without the support and enthusiasm of the staff at herbaria around Switzerland (herbaria of University and ETH Zurich, Universities of Basel and Neuchatel, and Museum of Natural History Chur), in particular Hugo Berger, for which we would like to say thanks. We would also like to thank Rachel Imboden, Samuel Stolz, Aino Kulonen, Adrien Gaudard, Louis Quéno, Amy MacFarlane, Ueli Schmid, Lorna Holl and Pirmin Ebner for their invaluable help in the field and in the lab
Keywords
- Global change ecology
- plant population and community dynamics
- plant-climate interactions
- Plant development and life-history traits
- Herbarium collections
- Plant functional traits
- Alpine ecology
Access to Document
- Jaroszynska_etal_JoE_Resampling_Alpine_Herbarium_VoR
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. © 2023 The Authors. Journal of Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society https://creativecommons.org/licenses/by/4.0/