Rerun: Sequestering Carbon using Compost and Grasslands, with Whendee Silver

Climate Break

Carbon Sequestration

Carbon sequestration is the process of capturing and storing atmospheric carbon dioxide to slow the pace of climate change. There are two major types of carbon sequestration: geologic and biologic. Geological carbon sequestration injects carbon dioxide captured from an industrial or energy-related source into underground geologic formations. Biological carbon sequestration refers to the storage of atmospheric carbon in vegetation, soils, woody products, and aquatic environments. While carbon dioxide (CO2) is naturally captured from the atmosphere through biological, chemical, and physical processes, some artificial sequestration techniques exploit the natural processes to slow the atmospheric accumulation of CO2.

Soil Carbon Sequestration and Climate Change

The exchange of carbon between soils and the atmosphere is a significant part of the world’s carbon cycle. Carbon, as it relates to the organic matter of soils, is a major component of soil and catchment health. However, human activities including agriculture have caused massive losses of soil organic carbon, leading to soil deterioration. California´s Healthy Soil Initiative is one program in the state working to promote the development of healthy soils in efforts to increase the state´s carbon sequestration, prevent soil deterioration and reduce overall greenhouse gas emissions.

Soil carbon sequestration is a process in which CO2 is removed from the atmosphere, primarily mediated by plants through photosynthesis, with carbon stored in the form of soil organic matter. Many scientists agree that regenerative agricultural practices can reduce atmospheric CO2 while also boosting soil productivity and health and increasing resilience to floods and drought.

UC Berkeley researchers found that low-tech agricultural management practices such as planting cover crops, optimizing grazing, and sowing legumes on rangelands, if instituted globally, could capture enough carbon from the atmosphere and store it in the soil to reduce global temperatures 0.26 degrees Celsius – nearly half a degree Fahrenheit – by 2100. However, critics say that because biological sequestration isn't permanent and can be hard to measure, it's only part of the climate solution and not a substitute for reducing emissions.

Whendee Silver

Dr. Whendee Silver is the Rudy Grah Chair and Professor of Ecosystem Ecology and Biogeochemistry in the Department of Environmental Science, Policy, and Management at U.C. Berkeley. She received her Ph.D. in Ecosystem Ecology from Yale University. Her work seeks to determine the biogeochemical effects of climate change and human impacts on the environment, and the potential for mitigating these effects. The Silver Lab is currently working on drought and hurricane impacts on tropical forests, climate change mitigation potential of grasslands, and greenhouse gas dynamics of peatlands and wetlands. Professor Silver is the lead scientist of the Marin Carbon Project, which is studying the potential for land-based climate change mitigation, particularly by composting high-emission organic waste for soil amendments to sequester atmospheric carbon dioxide.

Continued Reading

• The potential of agricultural land management to contribute to lower global surface temperatures
• Technical options for sustainable land and water management
• Soils help to combat and adapt to climate change by playing a key role in the carbon cycle
• The solution to climate change is just below our feet
• Soil as Carbon Storehouse: New Weapon in Climate Fight?
• Soil Carbon Sequestration Impacts on Global Climate Change and Food Security

Organizations

• Silver Lab, UC Berkeley
• Carbon Management and Sequestration Center, Ohio State University
• Food and Agricultural Organization, the United Nations

Related Episodes

• Collaborating with farmers on climate-friendly practices, with Alameda County Resource Conservation District

For a transcript, please visit https://climatebreak.org/sequestering-carbon-using-compost-and-grasslands-with-whendee-silver/