Seed persistence in soil seed banks of sub-Alpine Bogs and Fens – Progress Report March 2016

Lydia Guja | 2016


Project background

Alpine Sphagnum bogs and associated fens (ASBAF) are a Nationally-listed endangered wetland community in the Australian Alps. Climate change is predicted to be the single greatest threat to the biodiversity values of the Australian Alps catchments, especially ASBAFs. More frequent and hotter fires, the drying out of important Sphagnum bogs and wetlands, and overall ‘up-mountain’ movement of vegetation communities are likely to occur by 2050. The detailed knowledge required to appropriately conserve, manage, and restore endangered ASBAF communities in the face of rapid climate change is lacking. Current restoration techniques for bog and fen communities rely on slowing water flow and minimising erosion through damming, and shading to encourage Sphagnum regrowth. Although successful to date, these practices rely on existing soil propagules for plant re-establishment and the practices will likely become less viable under climate change. Shorter disturbance regimes, such as changes to fire frequency and intensity, will limit the ability of plants to reach reproductive maturity and replenish the soil seed bank between disturbance events. To improve the conservation, management, restoration and resilience of Endangered ASBAF plant communities we require a clear, scientifically-based understanding of key processes that underpin re-establishment of these communities. One of the most critical processes requiring research is re-generation from seed, and in particular the persistence of seeds in soil seed-banks. Understanding how long soil seed banks persist will ensure that post-disturbance restoration is not relying on diminished seed supply. Accordingly, the Australian National Botanic Gardens (ANBG) is conducting projects focussed on expanding ex situ conservation seed collections that will be used to provide the knowledge required to collect and use seed to supplement current restoration techniques. The scientific project reported here, supported by the Australian Alps Liaison Committee (AALC) (reference A13- 14/CC1), aims to promote understanding of the persistence of seed in endangered ASBAF communities; this has Alps-wide implications and will assist in efforts to mitigate biodiversity loss due to climate change. Research outcomes may also inform the development of operational, on-ground, management actions in the National Recovery Plan for ASBAFs.