Nature's nutrient cycle

Soil plays a crucial role in nature’s cycles, including the nutrient cycle, which involves how much soil organic matter — i.e. carbon, nitrogen and phosphorus — is taken up and stored in soil. Organic compounds, such as leaves and root tips, are broken down to simpler compounds by organisms living in soil before they can be used by plants. Some soil bacteria convert atmospheric nitrogen into mineral nitrogen, which is essential for plant growth. Fertilisers introduce nitrogen and phosphates to induce plant growth but not all amounts are taken up by plants. The excess can enter rivers and lakes and affect life in these water ecosystems.