The Surprising Reason Rare Plants in the Arctic Could Face Extinction
By Nikki Williamson
The Arctic tundra is home to a variety of species that are adapted to living in extreme conditions. With the climate of our earth changing, the species of plants and animals in the Arctic are going to be impacted at a higher rate than at lower latitudes. A recent study conceived by Eric Post, a professor at UC Davis, has been monitoring the change in biodiversity and species abundance in Kangerlussuaq, Greenland. The study was observing the potential decline in rare Arctic plant species, but why?
The Phenomenon of Arctic Amplification
As hinted at above, climate change affects the Arctic at a higher rate than the rest of the world. Studies show that the Arctic is warming at two to three times the global rate. This phenomenon happens due to the loss of sea ice caused by higher temperatures (Serreze, 2011). When this ice melts it leaves behind the darker ocean and land masses that absorb more energy from the sun than the reflective ice that once stood there.
As this area begins to warm it comes into question what species will be affected. That is where the research of Eric Post, Christian Pedersen, and David Watts comes in; exploring what the future of the Arctic may look like.
Predicting Long Term Changes in the Arctic
It’s hard to envision Greenland without its massive array of ice sheets, specialized animal species, and well-adapted plants. However, as our global temperature rises scientists have to dive into the possibility of what these areas will look like in the future. Herbivores may be pushed out of their natural habitats due to climatic events. The interactions these large herbivores have with their environment can change the abundance of common and rare plant species. Because of this perception, scientists manipulated the study site in Kangerlussuaq to mimic what would happen to the local plant species if temperatures increased and herbivory decreased.
Fifty experimental plots were set up in this 15-year long study. The plots represented areas of increased temperature, lack of herbivores, and a combination of the two. They were able to exclude the herbivores by creating wire fencing around enclosures. They amplified temperature using open-topped enclosures with warming chambers inside. The study observed 14 different species of plants, both rare and common. The study was looking at the overall change in abundance of plant species, as well as the fluctuation in the amount of common versus rare species. The goal of this study was to find out if warming temperatures, as well as the disappearance of large herbivores, could play a role in the possible declination or extinction of rare plants.
When caribou and other large animals aren’t in the area grazing and interacting with the plant species, the common plants tend to take over and rare species are more negatively affected. Herbivore exclusion alone reduced rare plant species by 71%. The findings show that temperature didn’t influence the abundance of rare plant species quite as much as herbivore exclusion. There is also the possibility that the rising temperatures will allow plants from lower latitudes to increase their range. The Arctic will be more hospitable to lower latitude organisms if the temperatures rise enough. This could increase plant biodiversity in a sense, but at what cost?
Why Should You Care?
The delicate region that is the Arctic Tundra is a difficult area for organisms to survive; plant diversity here is already relatively low. The grazing of large herbivores can maintain plant diversity and prevent common shrubs from taking over. Biodiversity in these fragile parts of the earth is of the utmost importance. We must protect the most vulnerable species, especially in areas as extreme as the Arctic. With temperatures rising at an unprecedented rate, and Arctic amplification at play, it’s only a matter of time before we see a shift in the abundance of these rare species.
What Can Be Done?
With muskoxen and caribou populations declining in the Arctic, conservation of these large herbivores could not only benefit the animals but could play an important role in the conservation of plant species. Think ‘two birds with one stone’. Changing the temperature of the globe is an extremely difficult task, but with increased conservation efforts for caribou and muskoxen, we could find a symbiotic balance. The Arctic is a rarity we can’t afford to lose, conservation and preservation of these lands should be prioritized accordingly.
Citations
Post, E., Pedersen, C. & Watts, D.A. 2022. Large herbivores facilitate the persistence of rare taxa under tundra warming. Sci Rep 12, 1292. https://doi.org/10.1038/s41598-022-05388-4
Serreze M., Barry, R. 2011. Processes and impacts of Arctic amplification: A research synthesis. Global and Planetary Change. (77) 85–96. https://doi.org/10.1016/j.gloplacha.2011.03.004
