Improved native understorey establishment in mine waste rock in Australia’s wet–dry tropics

Re-establishment of understorey in mine waste can be challenging because its physical, chemical and microbiological characteristics. This project investigated amelioration treatments for establishing native rock at Ranger uranium mine, including the addition fine sand, fertiliser, surface litter, incorporated organic matter, or a combination fertiliser litter. Trials were established shade house situ on waste-rock landform. Several grass legume species had seedling emergence growth being monitored. In situ, litter generally twice as many seedlings emerge did other tallest mean height most species, likely it created microclimate that retained moisture moderated temperature. house, no treatment significantly greater than control (except Acacia gonocarpa F.Muell. with litter). Fertiliser application resulted taller plants but effect which suggests under well watered conditions, plant is affected by nutrient deficiency, whereas field water supply main growth-limiting factor. When hot seasonally wet–dry climates, applying seeds may improve initial establishment.