Sustainable harvesting of grasslands can buffer large scale wildfires and the harvested biomass can be used for various products. Spinifex (Triodia spp.) grasslands cover ≈30% of the Australian continent and form the dominant vegetation in the driest regions. Harvesting near settlements is being considered as a means to reduce the occurrence and intensity of wildfires and to source biomaterials for sustainable desert living. However, it is unknown if harvesting spinifex grasslands can be done sustainably without loss of biodiversity and ecosystem function. We examined the trajectory of plant regeneration of burned and harvested spinifex grassland, floristic diversity, nutrient concentrations in soil and plants, and seed germination in controlled ex situ conditions. After two to three years of burning or harvesting in dry or wet seasons, species richness, diversity, and concentrations of most nutrients in soil and leaves of regenerating spinifex plants were overall similar in burned and harvested plots. Germination tests showed that 20% of species require fire-related cues to trigger germination, indicating that fire is essential for the regeneration of some species. Further experimentation should evaluate these findings and explore if harvesting and intervention, such as sowing of fire-cued seeds, allow sustainable, localised harvesting of spinifex grasslands. 1. Introduction The evergreen C4 hummock grass genus Triodia (“spinifex”) forms the dominant vegetation in Australia’s arid and semiarid regions, covering nearly one-third of the continent . Fire is a natural disturbance in spinifex grasslands that recycles nutrients and maintains biodiversity and plant community structure [1, 2]. Postfire native ephemeral grasses and forbs proliferate within few months but are gradually replaced by spinifex and a low cover of woody species [3, 4]. While the effects of fire in spinifex grasslands are well known, it is unclear whether it is the removal of the dominant vegetation (spinifex) or the fire cues that trigger the seed germination that maintains plant biodiversity in these ecosystems. We examined this by comparing harvested and burned spinifex plots near settlements in north-west Queensland. If fire is not essential for maintaining plant diversity, localised harvesting could be an alternative to fire in managing spinifex grasslands. Harvested areas could act as fire breaks and plant biomass could be used as feed stock for green products . Indigenous Australians have long burned and locally harvested spinifex grasslands for the purpose of hunting and
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