The soil is quite literary the base of our existence. All minerals and elements are present in the ground. The quality of the soil determines the quality of all that lives. The soil is not ‘one thing’, it’s build up in layers. The top layer, the topsoil, is most relevant to us. This layer, called the A horizon in science, contains organic particles and a stunning amount of micro organisms: bacteria, fungi, and microscopic ‘worms’. These organisms do a lot of work in the soil: they structure it, hold on to water and convert minerals from rocks, sand and clay to states that plants can absorb. They break down organic material, like wood and plant remains, to make nutrients available again. Without these microorganisms the soil would be dead. You’d have only rocks, sand and clay like in a desert. Without life in the ground there is no life on top of it either. The topsoil is our most basic and important resource.
Soil erosion happens naturally and it is a process that has created our landscapes. Because of activities of mankind, like agriculture and growing cities, our landscape has seen drastic changes causing erosion and land degradation to accelerate. Every year we loose about 75 billion tons (!!) of topsoil. That is an amount between 15 and 40 times the natural erosion (the local amount depends on the landscape and local climate). The main causes for erosion and land degradation are deforestation, chemicals used on the land, repeated plowing, monoculture cropping, overgrazing and extreme climate fluctuations (drought or heavy rains for example). Ultimately, if these practices are not reversed we will see widespread desertification, which in turn leads to further climate change. This also means that the speed at which these problems are occurring will accelerate.
Soil erosion by water has other detrimental effects. In heavy rains it is not only the living topsoil that washes downstream but also nutrients and chemicals. That in turn leads to sediment deposits in waterways, poisoning of the water and algae bloom caused by excess nutrient levels in runoff water.
Within Permaculture regeneration and protection of topsoil has our main focus. Without saving our basic resource it is not only pointless but even impossible to solve other issues like pollution, energy or social problems. In history a collapse of society often happened when fertile soil was depleted. This time, during our existence, this is a worldwide problem.
The UN made 2015 ‘the year of soils’. The problem of soil degradation is known by these institutes and most (if not all) governments. Still too little is done to address the problems. Short term economic gain, often by big chemical corporations, are considered more important. Nature can repair damaged soils and we can help the recovery speed up a bit. But since it’s a natural process no corporation can make a profit on it.
Without addressing topsoil erosion and soil degradation we’re facing a downright catastrophe in the near future. The first signs are visible already: dramatic loss of agricultural land, water shortages, more extreme climate (more droughts followed by heavier rains, which is a characteristic of a desert climate!) and desertification. This will be followed by food shortages and if not addressed by famine. If you live in an area where you don’t yet notice any of this, please realize that the magnitude of this problem worldwide will sooner or later also start to affect your life.
We can end this article on a more positive note. It is possible to regenerate broad degraded landscapes back to health. More and more examples are available where people demonstrate that we can reverse desertification. A good documentary to watch is ‘green gold’. http://topdocumentaryfilms.com/green-gold/
Now we have identified the main problem we face, we can concentrate on solutions. Implementing solutions is what Permaculture is all about!
Sources for this article:
Interesting research paper on if organic agriculture can feed the world (spoiler alert, yes it can!): http://www.worldwatch.org/node/4060[