Answer:
Deforestation, and desertification. Deforestation can cause desertification, and desertification can cause droughts. To address this issue of deforestation, we could stop using urbanizing Africa, and start rebuilding its ecosystems.
Step-by-step explanation:
No ecosystem can function without water, and in order to stop deforestation, we need to stop desertification, and vice versa. Deforestation causes desertification, because without trees, the water in the ground is easy (for the sun) to evaporate, and without water trees can't grow.