The University of Western Australia
The Use of Innovative Seed Enhancement Technologies to Overcome Barriers to Restoration Success In A Biodiversity Hotspot
New technologies are needed to overcome the diverse array of barriers to native plant establishment for achieving restoration success. Large parts of southern Australia have already passed beyond “safe limits” of environmental degradation. For low-moderate reinstatement of species diversity, 10-15kg/ha of seed is required, and with an average price of $2,800/kg (current commercial prices) it is therefore imperative that seed resources are used efficiently.
Water repellent soils are a major barrier to plant establishment globally, affecting >10M ha of arable sandy soils in southern Australia alone. Soil water repellency leads to decreased water infiltration and moisture retention in the seed zone with resulting poor germination and seedling survival. Weeds are another major barrier to native species in the southwest of WA and are known to change the nutrient status of soils and outcompete native species.
Recent developments that include ‘extruded’ seed pellets (seeds embedded in a soil matrix) with soil surfactants (wetting agents) and with activated carbon (herbicide protection) have shown promise in restoring native species in the Southwest of Western Australia. Lambertia inermis seedling emergence was 20% greater from pellets in comparison to bare seeds. For Banksia menziesii, pellets with a surfactant significantly improved the average survival of seedlings after a severe drought by 2.6 days. Trials with activated carbon pellets have shown to protect Jacksonia furcellata from harmful herbicides, targeting the removal of weeds.
Using novel methods of distributed temperature sensing (DTS) to aid in the quantification and capture of niche-level processes (e.g. fine-scale hydrological processes), we are now able to quantify the affects to which these pellets formulations influence water infiltration rates.
These proof-of-concept investigations into new technologies demonstrate the possibility of creating favourable microsite conditions for seedling establishment and improving the deployment of seeds, provide the necessary steps in the advancement of restoration programs across Australia.