Revegetation of Quarry Using a Complex Vetiver Eco-engineering Technique

摘要

Stone quarrying activities always result in a severe damage to the environment, vegetation and landscape. Revegetation for quarries, especially for quarried faces, however, is always a very thorny thing, and even a world-class difficult problem, which is still resolved unsuccessfully so far. The main reasons resulting in extreme difficulty for revegetation of quarried faces are because: 1) the surface is very glossy, and there is almost no any soil or loose substrate on it; 2) they are all quite steep, usually up to 70 - 80°, and even perpendicular to the ground; and 3) most of them are quite high, often up to dozens of meters and even up to over 100 m and therefore, are extremely difficult to carry out construction. Since 1999, the vetiver technique has been used to restore quarries in China. Through years of research and ex ploration, a complex yet innovative vetiver technique eventually emerged. Combining the traditional vetiver technique with special cement concrete troughs and construction methods, the new technique successfully solves the problem of quarried face revegetation. Like the traditional vetiver technique, the new one aims to establish a permanent, stable ecological system on the quarried face taking vetiver's excellent slope stabilizing property and collaborating with the excellent ecological characteristics of other strongly adaptive species. Its core mechanisms are: 1) special troughs made from armored concrete and particular construction technique; 2) hedgerows formed mainly by vetiver and established on the troughs; 3) a rationally spatial configuration composed of trees, shrubs, grasses and lianas, and an effective nutrient-recycling system coming from the configuration; and 4) special moisture-and nutrient-preserving measures. The new technique, has been testified to be effective, rapid, persistent and relatively cheap. It costs only 20-50% of the present engineering techniques. As such, it is worth disseminating and applying in South China and even around the tropical and subtropical regions of the globe. Currently, the technique has been accepted and heard as a patent by the China National Intellectual Property Bureau.