Today is Thursday, January 4, 2024.
The strong air temperature warming between the 1950s and 2016 in the Antarctic Peninsula region exceeded the global average warming with evident impacts on terrestrial ecosystems.
Recent research found that as temperatures warm two native Antarctic flowering plants are spreading rapidly, involving their capability to colonize new sites, as well as their areal expansion on the island.
Antarctic hairgrass (Deschampsia antarctica) spread five times faster between 2009 and 2018 than between 1960 and 2009.
And Antarctic pearlwort (Colobanthus quitensis) increased almost ten times more.
According to the study, which provides one of the longest records of changes in vegetation in Antarctica ever made, the primary driver of change is warming summer air. In situ warming experiments also confirmed greater biomass allocation to higher leaf carbon gain of these two species, due to enhanced photosynthetic assimilation. These features suggest future warming would improve vegetative growth of these species.
A secondary reason is there are fewer fur seals on the island, which trample on the plants. It is not known why the number of seals has declined but it is likely to be related to changes in food availability and sea conditions.
The report also mentions that in Antarctica, several studies have reported biotic and abiotic (1) responses to increasing air temperatures in both terrestrial and marine ecosystems but none had yet reported an acceleration, in particular following the short and strong cooling that occurred in the early 2000s. The ‘‘pulse’’ climatic event of the strong air cooling detected in 2012 did not appear to influence the vegetation community dynamics on this island. And after 2012, climate warming resumed with accelerated trends.
This trend of accelerated plant dynamics is in agreement with evidence reported in the Northern Hemisphere:
A strong increase in plant species richness has been reported on mountain summits across Europe in response to climate warming, with a 5-fold increase in 2007–2016 compared with 1957–1966;
Advances in plant phenology (2) have been reported in response to climate warming in North America and Europe, with more intensive impacts at higher latitudes above 60 N.
Click at the image below to read "Acceleration of climate warming and plant dynamics in Antarctica" including references to the above mentioned studies.
Study was conducted at Signy Island, South Orkney Achipelago, jointly by scientists from Universita` degli Studi dell’Insubria, Universita` degli Studi di Torino, British Antarctic Survey and University of Johannesburg.
(1) Biotic factors are living things within an ecosystem; such as plants, animals, and bacteria, while abiotic are non-living components; such as water, soil and atmosphere.
(2) Phenology. The study of cyclic and seasonal natural phenomena, especially in relation to climate and plant and animal life.
