But people stopped using this method with the coming of subsidized farming. This financial support is aimed only for crop fields of pastures, not both. This way, farmers do not have stimuli to rotate their crops; even the opposite is true.

But the consequences are catastrophic. During the 1930s in the vast prairies of the USA, some unseen phenomena started to take place. Before the colonists, this land was one of the biggest grasslands in the world, supporting the biggest population of bison. By turning these lands into crop fields for corn without crop rotation, the soil started to erode, and the strong winds during these years blew it away. The locals witnessed one of the biggest sandstorms ever seen in North America.

The problem with soil erosion is very serious. If we don’t take some measures, we might end like the people in Mangaia fighting for food but on a much bigger scale.

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THE WATER PROBLEM

Agriculture is using 70% of all the water one person needs in a day. And this is creating big problems.

The soil

problem

or centuries the little island in the Pacific Ocean called Mangaia was covered with thick and ancient forests that protected the land from the fury of the sea. These forests made it possible for fertile soil to develop. A complex ecosystem was created, which boosted the rich diversity of plants and animals. 

But as the first settlers began to arrive, they also started to cut down trees to make space for crops. This way, they destroyed the natural barrier between the island and the ocean. With time the water and wind blew away the fertile soil, and agriculture became impossible.

The lack of food forced people to search for alternative sources for food like rats and other people.

Today we are doing absolutely the same but on a much bigger scale. Of course, we are not eating each other. But we are making the same mistakes, and the fertile soil which we rely on for food is disappearing with rates much bigger then it regenerates.

We take the soil as a fixed part of our planer. But this is not true. It is continually changing. Part of it gets blown away by the wind or washed away by the water. But a lot of soil is being created too. When plants, animals, fungi, and rocks break down.

Most of the plants we grow are annual. At the beginning or the end 

The problem is that the way we do agriculture doesn’t allow the soil to regenerate, and we are breaking the fragile balance which supports the soil.

of the year we plant them, they grow up, collect them, and we leave the soil on the mercy of the elements.

The biggest problem is that we leave the soil uncovered during the winter. If there is no snow, the problem gets even more significant. If there is snow, which is the better case when it melts, it carries the soil with it on the bottom of a river or a lake or a sea. And these are not places where you can grow food.

There are a lot of possible solutions to this problem. We can add shrubs where the soil can attach to or even better - trees. Or we can also leave the unused parts of the plants to cover the soil. The problem with most of these is they use parts of the land. And this means we will grom less food.

Interestingly, a century or so ago, people did not have this problem. Thanks to a method invented thousands of years ago - the so-called crop rotation. And mostly the rotation of crop fields and grasslands, which can be used as pastures.

It turns out that when fields with crops and pastures are rotated, that dramatically enhances the soil and prevents its erosion. Also, grasslands are incredibly efficient in combating global warming. They absorb carbon dioxide and bury it deep inside the soil.