Biodiversity is declining globally in response to multiple human stressors, including climate forcing. Nonetheless, local diversity trends are inconsistent in some taxa, obscuring contributions of local processes to global patterns. Arctic tundra diversity, including plants, fungi, and lichens, declined during a 15-year experiment that combined warming with exclusion of large herbivores known to influence tundra vegetation composition. Tundra diversity declined regardless of experimental treatment, as background growing season temperatures rose with sea ice loss. However, diversity declined slower with large herbivores than without them. This difference was associated with an increase in effective diversity of large herbivores as formerly abundant caribou declined and muskoxen increased. Efforts that promote herbivore diversity, such as rewilding, may help mitigate impacts of warming on tundra diversity.
Plants often thrive in their environments not just because of their genetics, but also through partnerships with fungal endophytes, which are fungi living inside the plants.
The study examined two Antarctic plant species, Colobanthus quitensis and Deschampsia antarctica, to see how these fungal relationships affect plant adaptation and survival in different habitats (hills vs. coast).
Findings showed that while both plants shared similar fungal diversity, C. quitensis had a broader, more flexible relationship with fungi, whereas D. antarctica formed specific, beneficial interactions with fungi mainly in coastal areas, highlighting different strategies for adapting to extreme environments.
The migration rate of Arctic rivers is crucial for the stability of local infrastructure and communities, as well as for controlling the flow of carbon and nutrients to oceans.
Conflicting views exist on whether permafrost slows down or speeds up river migration, complicating predictions in a warming Arctic environment.
New computational methods reveal that permafrost decreases erosion rates by 47%, and models predict that its complete thaw could accelerate river migration by 30-100%.
The environment of mountain ecosystems can change greatly in short distances as elevation increases. The effects of elevation change on the distribution and body size of carabid beetles were investigated at elevations of 750-2600 m in the Changbaishan Nature Reserve (Northeast China). The richness and abundance of carabid species decreased significantly as elevation increased.
Arctic soil microbial communities may shift with increasing temperatures and water availability from climate change. We examined temperature and volumetric liquid water content (VWC) in the upper 80 cm of permafrost-affected soil over 2 years (2018-2019) at the Bayelva monitoring station, Ny Ålesund, Svalbard. We show VWC increases with depth, whereas in situ temperature is more stable vertically, ranging from -5°C to 5 °C seasonally.
Northern herbivores significantly impact tundra ecosystems, but the effects of herbivore diversity on these ecosystems have been largely overlooked, especially with ongoing climate and land-use changes.
This systematic review analyzed numerous studies (201 articles and over 3700 individual comparisons) to understand how different levels of herbivore diversity (measured by functional group richness) influence ecosystem processes and functions in the tundra.
The findings highlight a concentrated body of research from specific locations, emphasizing the need for more comprehensive studies across diverse Arctic regions to grasp the full effects of herbivore diversity on ecosystem functionality.
