Polar, Mountain and Alpine Plants in Climate Change

Polar, mountain, and alpine regions are characterised by a short growing season with long day length, mostly cool temperatures, and rugged terrains. A relatively rich flora can still be found, especially in some of the Arctic regions, even if low shrubs, sedges, grasses, and mosses dominate. Antarctica currently supports only two native vascular plant species, but high numbers of mosses, lichens, and liverworts (Convey and Biersma 2024). Plant life in these areas has evolved to cope with rapidly fluctuating abiotic conditions across diurnal timeframes, but with consistent seasonal patterns (long winter and short growing season). However, climate change is strongly affecting seasonal patterns and is increasing the variability of short-term abiotic extremes, which may exceed the physiological capabilities of native plants in polar and mountainous regions. This special issue includes insights into plant response to cold extremes, plant adaptations across elevational gradients, plant response to drought and heat stress in field manipulations, as well as modelled carbon balance of Sphagnum peatlands, and how environmental pollutants influence plant responses to climate extremes and how this is mediated by fungal endophytes.