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Abstract Fine‐scale microclimate variation due to complex topography can shape both current vegetation distributional patterns and how vegetation responds to changing climate. Topographic heterogeneity in mountains is hypothesized to mediate responses to regional climate change at the scale of metres. For alpine vegetation especially, the interplay between changing temperatures and topographically mediated variation in snow accumulation will determine the overall impact of climate change on vegetation dynamics.We combined 30 years of co‐located measurements of temperature, snow and alpine plant community composition in Colorado, USA, to investigate vegetation community trajectories across a snow depth gradient.Our analysis of long‐term trends in plant community composition revealed notable directional change in the alpine vegetation with warming temperatures. Furthermore, community trajectories are divergent across the snow depth gradient, with exposed parts of the landscape that experience little snow accumulation shifting towards stress‐tolerant, cold‐ and drought‐adapted communities, while snowier areas shifted towards more warm‐adapted communities.Synthesis: Our findings demonstrate that fine‐scale topography can mediate both the magnitude and direction of vegetation responses to climate change. We documented notable shifts in plant community composition over a 30‐year period even though alpine vegetation is known for slow dynamics that often lag behind environmental change. These results suggest that the processes driving alpine plant population and community dynamics at this site are strong and highly heterogeneous across the complex topography that is characteristic of high‐elevation mountain systems.
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Plant traits, microclimate temperature and humidity: A research agenda for advancing nature‐based solutions to a warming and drying climate
Abstract Climate models predict at least another 1.5°C warming in the next 75 years. This warming drives increased atmospheric drying and a global increase in the severity and duration of ecological drought. Vegetation has the capacity to reduce microclimate temperatures and atmospheric aridity.All species of plants create shade, move water, evapotranspire, humidify the air around them, and affect the temperature and vapour pressure deficit of the environment. Vegetation can thus act as a nature‐based solution to warming and atmospheric drying.These microclimate modifications likely depend on the traits, functional groups and diversity of the plant community. Vegetative feedbacks on microclimate are strong enough to buffer some plants against the negative impacts of warming and drying (e.g. facilitation).Synthesis: Here we present, for the first time, a trait‐based framework that can be applied across study systems for assessing microclimate temperature and humidity under vegetation. This framework includes multiple new hypotheses for future work in this area. We emphasize that a systematic examination of trait–microclimate relationships will enable us to use vegetation as a nature‐based solution to warming and atmospheric drying in a changing climate.
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- Award ID(s):
- 2143186
- PAR ID:
- 10503479
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Journal of Ecology
- ISSN:
- 0022-0477
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1111/1365-2745.14313
