![]() ![]() We propose that fluid seed drilling techniques (suspending uncleaned harvested seed in a cellulose-based gel matrix, which may then be injected into the soil with a mechanical planter) may overcome these challenges. Harvested seed must be cleaned of chaff to allow mechanical planting, which can exclude small seeds. All rights reserved.Ĭommercial seed mixes and various mechanical planting methods have been implemented to overcome barriers to successful restoration of degraded grasslands but their effectiveness in aiding the restoration process has been understudied. It is necessary to determine the longer‐term impacts of switches in disturbance regimes, and whether recovery thresholds have already been crossed. This suggests that seed‐ and/or dispersal‐limitation may limit passive restoration outcomes in fragmented landscapes. Positive outcomes for other disturbance shifts (grazing → mowing, or cultivation → grazing) occurred when the disturbance type was accompanied by seed addition, or in landscapes where dispersal from nearby remnant sites was possible. We found mostly no change in native and exotic species richness when management changed from stock grazing to fire (at least in the short term ≤10 years). We review literature that reports instances where there has been a change in disturbance type to examine how grasslands respond to disturbance switching. Here, we examine if the change in disturbance type-a disturbance switch-improves the native composition of grasslands. Recently, native grasslands have been acquired to improve the reservation status of the threatened community and management strategies have been implemented that involve the removal of livestock grazing and the re‐introduction of fire or other biomass reduction methods. ![]() Changes in disturbance type, particularly the removal of Indigenous fire and the introduction of livestock grazing, resulted in the local extinction of fire‐dependent and grazing‐sensitive native species, and led to an increase in exotic species. Temperate native grasslands in Australia have been decimated across their range since European colonisation (>200 years ago), and the few remaining remnants are mostly fragmented and degraded. Understanding the environmental requirements needed for seed germination, together with an appropriate pre-treatment before sowing, can speed up seedling emergence and increase total emergence when using native Poaceae species for seed-based restoration. ![]() Generally, soil type did not influence emergence rates for either GEC or SET. Seedling emergence from seed cookies was low in all three species (<15%). bladhii, total seedling emergence was the highest (36% in both soils) for primed seeds with KNO 3. spicigerum, priming and/or coating with KNO 3 + SW had the highest cumulative emergence. Incorporating GECs together with seed priming or seed coating treatment significantly increased seedling emergence rates and promoted earlier emergence as compared to the untreated control. Laboratory germination percentages achieved were <50% for all species, limited by dormant seeds. The seeds were exposed to different germination-enhancing chemicals (GECs, namely smoke water (SW), potassium nitrate (KNO 3 ) or a combination (SW + KNO 3 )) and treated with three different seed enhancement technologies (SETs, namely seed priming, seed coating or seed cookies) then sown into two contrasting soil types (sodosol or black vertisol). In this study, germination biology of three Australian native Poaceae species, such as Cymbopogon refractus, Capillipedium spicigerum and Bothriochloa bladhii, was investigated. For Australian native Poaceae species, seed quality and dormancy can impose constraints on restoration success. Using seeds to restore natural ecosystems has a greater chance of success if the seeds used are ready to germinate given appropriate environmental conditions. ![]()
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