Field evaluation of seven grasses for use in the revegetation of lands disturbed by coal mining in Central Queensland

Abstract

Pasture-based systems, dominated by the tussock forming Cenchrus ciliaris cv. Biloela (buffel grass) and the stoloniferous Chloris gayana cv. Pioneer (rhodes grass), are commonly used in the revegetation of lands disturbed by coal mining in the Bowen Basin of Central Queensland. Although able to establish quickly under favourable conditions, neither species has proven entirely suitable for use in this situation, particularly in providing effective ground cover for erosion control on the re-contoured post-mining landscape. The aim of this study was to evaluate a range of new pasture grasses, with the objective of identifying accessions better adapted to the edaphic and climatic conditions of the areas requiring revegetation. Seven grasses were evaluated, on both bare spoil and replaced topsoil, at the Saraji mine, about 25 km north of Dysart. Differences in establishment between grasses were limited, although establishment was up to 5 times greater in the replaced topsoil plots. Urochloa mosambicensis CPI 60128 exhibited better seedling survival (up to 8 times greater) and produced a more extensive ground cover (up to 3 times greater) than the stoloniferous control Chloris gayana cv. Pioneer under conditions of below average rainfall (rainfall was below average in 70% of the months). This work resulted in the commercial release of U. mosambicensis CPI 60128 as cv. Saraji.