Concepts of soils

In this chapter we will explore some changes of people’s perceptions of soils and their classification as background for the dominant concepts of today. Close your eyes for a moment and imagine that when you open them you are at the beginning of human time, a hunter and gatherer somewhere in the world, isolated, with barest of necessities, and you are hungry. By trial and error and stories passed on to you, you now know which plants and berries are okay to eat and how to stalk and kill animals and how to fish for your survival. As a keen observer you detect the location of specific plants and the common habitats and behaviour of the animals that become your food. You can’t go far from where you are because your source of protein is here – not somewhere else. One or two million years pass by almost unnoticed. Close your eyes again and when you open them imagine that you look beyond the bank of a river to small plots of irrigated land where grain is growing. Fish are still an important protein source but now with harvestable and storable grains you can easily carry protein with you. The world around you opens up to exploration and conquest. Ideas and technology are transferable to faraway places. It is known locally that some lands are better than others for producing grains and are easier to prepare and manage. Your observations reveal many new relationships – for instance, that the effort expended and the yields returned are geographic for the most part. Throughout the Holocene, starting 11–12 000 years BP, there has been evidence of increasing use of land for cultivated grains and fruits. From the early habitats at the edge of sloping uplands to the later migrations into the lower lying river and lake plains, there arose complex systems of irrigation enabling the blossoming of early civilizations. Egypt, the Middle East, India, China, and