Abstract ID: 3.12158 | Accepted as Talk | Talk/Oral | TBA | TBA

Alpine snowpatch plant communities (synonymous with snowbank or snowbed communities) are re-occurring assemblages of plants that exist where snow lies late into the summer. On the Australian mainland, these occur on the south-east side of high elevation ridges and mountain sides, in the lee of the prevailing north-westerly winds. The highest elevation snowpatches can develop impressive cornices of snow that may be up to 10 m deep. Snowpatches are one of the rarest communities in the Australian alpine landscape due to topographical constraints and the restricted nature of the alpine zone in general, and are listed as critically endangered ecological communities. Snow is the primary environmental driver in a snowpatch community, creating a repeating pattern of melt every year and thus predictable zones of growing season length across the snowpatch. Soil water availability is also determined by the regular pattern of melting snow, and this affects nutrient cycling and litter decomposition processes. Many species time their growth and phenology to these snowmelt patterns. Snow also determines the type and function of species that grow in different snowmelt zones; those which are relatively taller and larger-leaved (competitive and productive) tend to be around the perimeter of a snowpatch where snow melts earlier, compared to the shorter and smaller leaved species which grow in the centre of the snowpatch where snow melts last. Shrub species are also more abundant around the perimeter of some lower-elevation snowpatches, as they are restricted by their requirements for relatively longer growing seasons. However, lasting snow cover is dwindling and species abundances are changing…

In this update, I will present some recent research on how the inter-linked threatening processes of snow cover duration and warming temperatures have been driving changes in the composition of snowpatch communities and how this has led to ecological collapse in some areas. I will also describe some potential mechanisms for snowpatch plant regeneration from the soil seed bank and outline some options for how these communities might be managed into the future.