Today was the final day of the Perth Mountain Meeting and after the close of the conference, TeamShrub drove to the hills to summit a mountain and check out the alpine diversity. The peak was so diverse with red deer, grouse, mountain hare, and one of our favourite shrubs Empetrum (crowberry) that we had to jump for joy!
It was a great week! TeamShrub was representing with talks by Sandra and Anne and a poster by Haydn. We also met up with friends and collaborators from through out the years, including the crew from the WSL in Davos and my own PhD advisor David Hik.
The major take-home messages of the conference for us were:
- Alpine tundra is likely warming and changing just as fast as Arctic tundra, though some factors such as day length, snow conditions, and distance to treeline plant communities differ. Thus, somewhat different future trajectories can be expected for plant communities on the mountainous versus high-latitude sides of the tundra biome.
- Microclimate matters. So, if you are a plant, it might be just as easy to move around a mountain rather than just climb towards the summit to follow your thermal niche.
- Plant diversity is increasing on alpine summits with warming, but the plants that come and go could just be “summit tourists” and might not be there to stay.
- Treeline advance is likely controlled by a variety of factors besides just climate, such as plant competition and herbivory, such that warming won’t always result in trees moving into the tundra.
Check out our tweets for more info on the conference @TeamShrub.
Sandra gave her very first talk at an international conference entitled: “The influence of plant size on the climate sensitivity of tundra shrubs”. She told us all about her analysis of the climate sensitivity of tundra shrubs of different heights. Her hypothesis that taller shrubs are more climate sensitive because they should be better competitors and more linked to atmospheric conditions, was not supported by her analysis of the ShrubHub dataset. This finding leads on beautifully into the rest of her PhD research, where she will explicit test competition and shrub-shrub interactions using dendroecology in tundra ecosystems across the Yukon Territory and Northern Quebec (see details on field data collection in previous blog posts). Sandra did a fabulous job of presenting a complicated analysis on shrubs to an audience of treeline enthusiasts!
It was also an international conference first for Haydn with his poster entitled: “Arctic and alpine tundra vegetation change has no net impact on tundra litter decomposition rates”. Haydn pulled out all the stops putting together a poster that was a work of art, clearly communicated his scientific message, and even included take-away tea bag business cards. Haydn used plant traits to predict community-weighted decomposition. He found that although decomposition is greater at warmer sites around the tundra biome, with warming, plant composition changes. Over time, there is an increase in more decomposable species (e.g., deciduous versus evergreen shrubs) from less decomposable functional groups (e.g., shrubs). Thus, these two effects offset each other leading to no net change in tundra litter decomposition. This is a natural launching off point into other elements of Haydn’s PhD including the tundra teabag experiment initiative that he is leading.
Anne presented the talk: “From the top of the mountain to the top of the world: biogeographic patterns in plant functional traits across the tundra biome”. Anne has found very strong patterns of plant traits along tundra climate gradients. And, what is particularly exciting is that the changes in plant traits across space match up well with the changes in the same traits over time with warming. For example, Anne has looked at the patterns of specific leaf area (SLA), which describes leaf area and mass and is related to energy capture through photosynthesis, water-use efficiency and decomposability of plant leaves. At warmer sites, the community-weighted SLA is higher versus colder sites. And over time with warming, SLA is also increasing across the tundra biome. Anne’s analysis also demonstrates the importance of within versus between species variation in plant traits, such as for example with patterns of canopy height, which need to be incorporated into projections of tundra ecosystem function overtime.
Stay tuned to hear more about the developing manuscripts of these three exciting projects on TeamShrub…
Our week began and ended with climbing a mountain, which seems very appropriate for a conference all about mountains and a research team that loves summiting peaks, tundra (or pseudo-tundra like we have here in Scotland) and shrubs like this beautiful bell heather (Erica cinerea)!