Environmental Disruption and Collapse of Civilization.

I guess you have studied in school about the lost civilizations, like Mayan or Aztecan.

But then, did you know that most of the lost civilizations are caused by Environmental Disruption?

1. Civilization develops.
2. Wealth grows.
3. Population grows.
4. To maintain the standard of life, Natural resources are exploited.
5. Environment becomes naturally unrecoverable.
6. Natural resources are exhausted.
7. Civilization collapses.

These steps were repeated over the centuries.

Especially WATER was essential in life, and when body-of-water is once polluted, it's very difficult to recover, thus people had to move from one place to another.

Another may be ecocide, usually by too much hunting, bringing non-adoptable introduced species, overgrazing, or deforestation.
And especially deforestation is grave.

As you know, largest desert in the world is Sahara desert, in Northern Africa.
The southern boundary of Sahara desert is called "Sahel", but this desert is growing toward south, 5km every year.

Once the surface is exposed due to deforestation or any other causes, erosion takes place either by rain or wind.
Barren terrain is hardly recovered.
Moreover, forest can keep some amount of water in soil, but Barren soil can't.
This makes landslide easier to occur.

On other hand, There are many uneducated people who thinks "trees come up spontaneously".
They don't have an idea of afforestation.

Perhaps educating them about afforestation while planting trees will be more effective for stopping desertification than simply planting trees.

And of course, we have to prevent from repeating the steps of collapse of civilization.