Lost soil
Due to overgrazing, chemical-intensive farming techniques, deforestation and other threats, about a third of the world's soil is considered degraded. On top of that, an estimated 75 billion metric tons of soil are lost every single year — the equivalent of more than 200,000 Empire State Buildings. Replenishing lost soil is no easy task — it takes more than 500 years to create 1 inch of topsoil.