Conventional agriculture causes increased greenhouse gas emissions, soil erosion, water pollution, and threatens human health. Organic farming has a smaller carbon footprint, conserves and builds soil health, replenishes natural ecosystems for cleaner water and air, all without toxic pesticide residues. While organic farming tends to enhance soil health and conventional practices degrade it, relying on tillage for weed control on both organic and conventional farms degrades soil organic matter and can disrupt soil life in ways that reduce crop mineral uptake and phytochemical production. Soil organic matter significantly improves the soil's capacity to store and supply essential nutrients (such as nitrogen, phosphorus, potassium, calcium and magnesium), and to retain toxic elements. It allows the soil to cope with changes in soil acidity, and helps soil minerals to decompose faster.