Ecological erosion control on coal-spoil banks: an evaluation

The relative merits of slope protection by forestation and by mechanical protection with contour wattles are evaluated for a steep. 17-18degrees, embankment of coal-briquette spoils, where drought and spoil properties prevent the establishment of ground vegetation. Ground loss, monitored for 6 years by erosion pins, shows that both treatments reduce the development of surface flow pathways. However, inter-rill soil losses are not significantly smaller on the wattle-protected than on the unprotected control slope. By contrast, ground losses under forest (1.9 mm year(-1)) are significantly smaller than on either the unprotected slope (7.0 mm year(-1)) or that protected by wattles (6.2 mm year(-1)). Ground losses from sites with > 20% leaf litter cover average 0.54 mm year(-1) and never exceed 3.5 mm year(-1). (C) 2002 Elsevier Science B.V. All rights reserved.