Amelioration of toxic conditions in miner in south Africa
Reforestation often involves addressing toxic site conditions . Landfills can have toxic liquids and gases mine tailings can have extreme PH values or toxic levels of metals in addition to surface compaction or erosion problem reforestation of dunes mined for various ores in south africa involved topsoil replacement windbreaks and sowing of various grasses that provided a nurse crop for slower-germinating native Acacia karoo trees from the seed bank. The acacia trees, promoted soil development through nitrogen fixation and were gradually replaced by larger native trees. In this case normal succession processes replaced early intensive manipulation . However it is often difficult to restore some semblance of predisturbance vegetation due to alterations in drainage , fertility and even topography . forests may remain stunted if they do colonise toxic sites, and reclamation goals are often more modest than in less toxic situations.