Conventional agriculture in the world we know today is mostly industrial and mechanized. This system of agriculture aims to mass produce certain types of food and plants that are traded world over to register a significant profit by certain companies. While I this description of the industrialised agricultural system is a known fact and highly oversimplified, I do this mainly to cut to the chase. In essence, the industrialised methodology of agriculture that prevails today has an adverse effect on the quality and arability of soil.
Soil is a renewable resource that is a product of biological and chemical processes that result in its creation and fertility. This soil contains a multitude of species like ants, fungi, earthworms and organisms. It is estimated that a single centimeter of healthy nutrient rich soil takes approximately 200 years to form in wet tropical areas. In milder climates, this timeline extends to 400 years and more, provided erosion of the forming soil is at a minimum. This long process for the formation of naturally occurring fertile soil and the damage that it faces due to industrialized farming today is a reason for concern. Vandana Shiva says more about this in the video below (at 41:52 onward).
There are many ways of looking at this matter, but in my opinion in boils down to the inherent global land quality and the methods by which infertile land is treated. Inherent global land quality looks at land quality in areas of the world and assesses its resilience and performance. This land quality, however is negatively affected by the excessive use of chemical fertilizer and erosion among other factors. David Montgomery, a University of Washington geologist claims in his book, `Dirt: The Erosion of Civilizations` that “the world today is losing soil 10 to 20 times faster than it is replenishing it. In some places it is happening much faster: northern China, sub-Saharan Africa, parts of the American West and Australia are already seeing large tracts of arable land disappear.“
Cleaner and more organic soil is an important resource that is depleting at a very steady rate today. The 10- 20 times increase in soil depletion, the 9.6 billion population projection for 2050 by the UN and the food dependence of this future population, paints a rather troubling picture. While the infertility of soil can be combated by chemical fertilizers, this is only a temporary solution. Better farming practices like lower degradation through chemicals, better erosion prevention techniques, no overgrazing and crop rotation techniques will help gradually restore the soil that we have today.