Deforestation
The plants and trees of the planet play a critically important; and necessary role in establishing and maintaining a healthy eco-system. They are entirely responsible for recycling carbon gases and producing the oxygen that it necessary for mobile forms of life to live and flourish. Fewer plants and trees leads to reduced levels of oxygen, reduced ability of recycling gases that are hazardous to oxygen breathers, as well as a reduced ability to maintain a stable and protected environment. Without plants and trees, all oxygen breathers on the planet would cease to exist.