Because crop 'waste' is waste only because you can't sell it or eat it.
Unlike other forms of waste, it's not toxic and it's not a pollutant. The
'wasted' part of the crop is intentionally plowed back into the ground in
many cases. It returns nutrients to the soil that were extracted to grow the
crop, and thus serves to partially replenish the soil for the next year's crop.
A student buries an ice cube in a pan of dirt and observes the dirt as the ice cube melts. This activity is a model of the formation of a kettle.
Answer:
reforestation
Explanation:
In the past decade, multiple African nations have been working together on projects that have the purpose to stop and reverse the land degradation. For this purpose, the people that live in the areas where the soil has been badly damaged or has been affected by the process of desertification have been mobilized, educated, and motivated to perform a reforestation. The reforestation generally has been taking place along the northern border of the region where it touches the outskirts of the Sahara Desert. The results have been excellent. The trees that have been planted are trees that produce fruits, thus food, they contributed to making the soil more fertile but also much more resilient to erosion, and the wells have started to replenish their water because of the protection from the trees above them that significantly reduce the evaporation.