Classification of anthropogenic soils of South Africa
ABSTRACT Man is part of the environment for a significant period of time in the history of earth’s ecosystem and is also influencing the land since his creation. In recent times the earth become so overcrowded and high tech practices are so much in use that there is no chance for the soil to recover after pollution or malprac- tices. There for the anthropogenic environmental footprint becomes more pronounce day by day. Several prehistoric evidences of intensive land uses eg farming, gardening, road building, exists. Unused land occupied by polluted soil or manmade materials could be changed into productive land if more knowledge is available about their properties and characteristics. This is only possible by means of a proper clas- sification system. The demand of any soil classification system is driven by the need to know more about the soil to improve and optimize existing production or soil uses eg crop production, infrastructure, environmental rehabilita- tion. If there are no such soil uses or if there are still enough other soils to occupy, there will be no need to know more about the soils. Little is known about the soil quality, management and production improvement of anthropogenic soils, but due to the ever increasing demand in land use, the situation demands more occupied land to be re- classified for land use purposes. The world wide issue about mine spoils and sustainable rehabilitation also requires a proper soil classification of these un-natural soils. To make this knowledge available for all present and future land users, contemporary and comprehensive classification systems should be devel- oped which should fit into the concept of an international system. The four main issues about classifying Anthrosols are: 1. What is a soil, when can a medium been regarded as a soil? 2. Some Anthrosols are exposed to soil forming processes which are not so pronounced in normal soils eg quick oxidation, acidification eg pH change from 9 to 3 in a short period of time. 3. Should conventional practices and definitions been revised for Anthrosols? Some characteristics and properties of Anthrosols are difficult to describe in context with the conventional system eg artificial structure (bricks, plastic bags, bottles in urban soils). 4. Should all polluted and disturbed soils been regarded as Anthrosols? All soils disturbed by humans eg ploughed fields, should not necessarily be renamed on the highest level (soil form). A technique of using prefixes on form and family level may alleviate the problem.