Soil Carbon Sequestration

What is Soil Carbon Sequestration?

Soil carbon sequestration is a natural process where CO2 is removed from the atmosphere and stored in the soil in a stable form. This process is primarily facilitated by plants through photosynthesis, as they absorb atmospheric CO2 and convert it into organic matter. When plants die, this organic matter is incorporated into the soil, contributing to the soil carbon pool. Soil carbon sequestration is a critical ecosystem service, enhancing soil health, fertility, and the global carbon cycle, playing a significant role in mitigating climate change by reducing atmospheric greenhouse gas concentrations.

The Mechanism Behind Soil Carbon Sequestration

The process of soil carbon sequestration involves multiple steps. It starts with photosynthesis, where plants absorb CO2 from the atmosphere. The carbon is then transferred to the soil through root exudates, litter fall, and plant residue. Soil organisms decompose this organic material, leading to the formation of humus, a stable form of organic matter that can store carbon for centuries. Agricultural practices such as crop rotation, cover cropping, reduced tillage, and organic amendments can enhance this natural process by increasing the amount of carbon that is sequestered in the soil.

Examples of Soil Carbon Projects

Klim is a leader in the regenerative agriculture movement in Germany. They are working towards a fully regenerative agricultural system in which farmers and society work together to protect the world's soil. This has a twofold effect, as their work results in effective carbon sequestration, while also ticking the boxes for several Sustainable Development Goals.

Common Types of Soil Carbon Sequestration Projects

Soil carbon sequestration projects can vary widely, depending on the agricultural and land management practices employed. Common types include:

Regenerative Agriculture: This includes sustainable farming practices such as maintaining soil cover and promoting crop rotation to enhance soil structure, reduce erosion, and increase carbon storage.
Agroforestry: Integrating trees with crops or pasturelands not only sequesters carbon in trees and soil but also improves biodiversity and land productivity.
Organic Farming: Using organic fertilisers and compost increases soil organic carbon content and soil health.
Restoration of Degraded Lands: Reclaiming and restoring lands that have been degraded by overgrazing, erosion, or chemical pollution can significantly increase soil carbon stocks.

Benefits Beyond Carbon Capture

The benefits of soil carbon sequestration extend beyond its potential to mitigate climate change. Improved soil health enhances water retention, which can lead to increased resilience to drought and flooding. Healthier soils also support higher agricultural yields, which can contribute to food security. Furthermore, practices that enhance soil carbon sequestration often lead to increased biodiversity, improved water quality, and enhanced ecosystem services, supporting overall environmental health and sustainability.