Articles | Volume 20, issue 20
https://doi.org/10.5194/bg-20-4259-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-20-4259-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
18 Oct 2023
Research article |
| 18 Oct 2023
| 18 Oct 2023
Above-treeline ecosystems facing drought: lessons from the 2022 European summer heat wave
Philippe Choler
CORRESPONDING AUTHOR
Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, 38000 Grenoble, France
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Badlands are heavily eroded landscapes where plants play a major role in controlling erosion. Using 40 years of aerial and satellite images of a badland site in the French Alps, we found that vegetation increased from 39 %–46 %, mainly due to young pines spreading onto bare ground. Vegetation colonization and retreat are linked to erosion and slope stability, seed dispersal, and climate. Understanding these relationships is needed to better predict how these landscapes may change in the future.
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Glacier forefields have long provided ecologists with a model to study patterns of plant succession following glacier retreat. We used remote sensing approaches to study early succession dynamics as it allows to analyze the deglaciation, colonization, and vegetation growth within a single framework. We found that the heterogeneity of early succession dynamics is deterministic and can be explained well by local environmental context. This work has been done by an international consortium.
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Short summary
The year 2022 was unique in that the summer heat wave and drought led to a widespread reduction in vegetation growth at high elevation in the European Alps. This impact was unprecedented in the southwestern, warm, and dry part of the Alps. Over the last 2 decades, water has become a co-dominant control of vegetation activity in areas that were, so far, primarily controlled by temperature, and the growth of mountain grasslands has become increasingly sensitive to moisture availability.
The year 2022 was unique in that the summer heat wave and drought led to a widespread reduction...
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