Experimental slab salvage and reinstatement after pipeline construction in a threatened grassland community

Summary The protection and management of grasslands is a priority to conserve biodiversity, particularly in fragmented landscapes subject to human-induced disturbance. We examined the success of salvage and reinstatement of multiple 90 m2 slabs of modified temperate grassland in a pipeline construction corridor in south-eastern Australia and compared it with a reinstated topsoil treatment (i.e. standard pipeline reinstatement practice) and an undisturbed control. Thirty-six plots (each 9 × 10 m) representing the three treatments were monitored across six locations, pre- and postconstruction every 3 months for 2 years. We sampled 18 vegetation/habitat variables to examine the effect of treatments over time. Introduced grass cover was consistently higher than native grasses for both treatments, and the cover of introduced grasses increased over time in both treatments. Conversely, control plots had considerably higher native grass cover than the slab and reinstated topsoil treatments. Native species richness was not negatively affected by the slab reinstatement process. Our results suggest that in this instance, slab replacement was an ineffective way to reinstate native grasslands, as it appeared to confer minimal benefit when compared to the standard practice of reinstating topsoil. This was most likely due to the high degree of disturbance to slabs during the reinstatement process.