This post is based on an article found in "The Guardian".
The vast majority of food is grown in the upper layer of soil. This fact makes soil possibly one of the most important factors to our continued existence. The problem is that we have been totally mistreating soil and the delicate balance required for it's health and productive contribution to plant growth.
The startling facts are, that over the last 150yrs nearly 50% of the planets most productive soils have all but disappeared. Soil sustaining croplands are eroding at ten fold the replacement rate using current farming techniques. It is estimated that in little over 50yrs the world could run out of the requisite top soil needed to sustain minimum nutritional intake.
The combined application of tilling, pesticides, chemical fertilizers and little use of cover cropping has resulted in fields stripped of nutrients, vital minerals and all the very necessary microbes that are required to grow a viable food crop.
Added to this, scientists estimate that it takes as long as 500yrs for soils to return to a healthy state, while it has taken most big-agri just over 100yrs to severely damage it. They are unsustainable numbers and we need to look at how we grow our food and care for our soil.
Unhealthy soils also lack the required nutrients we so desperately need from plants. Crop comparisons from the late 1990's when compared to crops from the 1950's show significant decrease in protein, iron, vitamin B2 & C and phosphorus.