Vascular plant success in a warming Antarctic may be due to efficient nitrogen acquisition

For the past 50 years there has been rapid warming in
the maritime Antarctic, with concurrent, and probably
temperature-mediated, proliferation of the two native plants,
Antarctic pearlwort (Colobanthus quitensis) and especially
Antarctic hair grass (Deschampsia antarctica). In many
terrestrial ecosystems at high latitudes, nitrogen (N) supply
regulates primary productivity. Although the predominant
view is that only inorganic and amino acid N are important
sources of N for angiosperms, most N enters soil as protein.
Maritime Antarctic soils have large stocks of proteinaceous N,
which is released slowly as decomposition is limited by low
temperatures. Consequently, an ability to acquire N at an early
stage of availability is key to the success of photosynthetic
organisms. Here we show that D. antarctica can acquire N
through its roots as short peptides, produced at an early stage
of protein decomposition, acquiring N over three times faster
than as amino acid, nitrate or ammonium, and more than 160
times faster than the mosses with which it competes. Efficient
acquisition of the N released in faster decomposition of soil
organic matter as temperatures rise may give D. antarctica
an advantage over competing mosses that has facilitated its
recent proliferation in the maritime Antarctic.