As California progresses toward its statewide goal of achieving carbon neutrality by 2045, carbon sequestration by natural and working lands becomes increasingly important.
Groundbreaking study identifies promising solutions for California’s carbon neutrality goals
A recent study by scientists at the Lawrence Livermore National Laboratory (LLNL), “Getting to Neutral: Options for Negative Carbon Emissions in California” finds that California needs to rely upon natural and working lands carbon sequestration to meet its ambitious carbon-neutral. Among the strategies reviewed are forest management practices to improve forest health and healthy soils practices to increase the amount of carbon sequestered in agricultural lands.
The natural and working lands recommended carbon sink actions were selected by scientists from more than 50 carbon storage pathways because of their low cost and productivity estimates. In total, the study estimates that natural and working lands can sequester an estimated 25.5 million tons of carbon annually. Other studies suggest that natural and working lands climate strategies can sequester even greater amounts of carbon, but not without scaling up and accelerating better management of natural and working lands.
Natural and working lands solutions
Aligning with the variety of natural and working landscapes present throughout California, the LLNL report recommends a suite of natural and working lands interventions to achieve emission reductions—including forest, wetland and grassland restoration, and healthy soils practices. Additionally, the report acknowledges the importance of reducing the likelihood of natural and working lands to act as a carbon emitter through land preservation and wildfire management.
Forest, wetland and grassland practices
Forest, wetland and grassland interventions consist of scaling up restoration practices that enhance carbon sequestration capacity. Reforestation and changes to forest management are among the recommended practices.
The potential for increasing carbon sinks in soils is well documented. As such, the LLNL researchers focused heavily on the potential of soil emission reduction drawing on their own extensive research. They propose California adopt a broad range of healthy soils practices—including cover cropping and composting—to meet the carbon sequestration potential of natural and working lands. They also acknowledge the importance of reducing the rate of carbon emission from soils, which can be achieved by limiting physical disturbance through reduced or no-till farming. In total, the near-term potential for carbon sequestration in California soils is estimated to be around 3.9 million tons of CO2 per year. This yields a total of 25.5 million tons of CO2 per year of sequestration potential by 2045 when combined with other natural and working lands solutions.
Figure 1. Figure 8 (pg. 26) from the report shows total emissions reductions associated with each soil conservation practice from NRCS Conservation Practice Standards. The bars show mean emissions reductions and the lines indicate the minimum and maximum values. Negative values indicate net positive emissions.
Advantages of natural and working lands solutions
Natural and working lands cover over 90 percent of California, and include farmland, rangeland, forests, wetlands, coastal areas, grasslands, and urban green space, which means little to no additional infrastructure investments are required for optimization. Coupled with the lowest price per ton of CO2 removed from the atmosphere, at an estimated weighted average of $11.4 per ton of CO2 emissions, natural solutions to carbon capture require low barriers to entry.
Natural and working lands solutions also offer important co-benefits to air and water quality, ecosystem and soil health, resilience to climate change, and protection of life and property through fire reduction. For example, because carbon is an essential component of soil, increasing carbon sinks in soil could improve soil fertility and contribute to negative carbon emissions. Their success does, however, depend on consistent funding, adoption of recommended practices across all of California, and multi-stakeholder engagement and support.
The time is now
California does not need to reinvent the wheel to reach the full potential of carbon sequestration in natural and working lands at the rate and cost estimated by the LLNL report. As an established leader in innovative climate solutions, California can leverage existing climate-smart agriculture programs like Healthy Soils and Alternative Manure Management Program (AMMP) to maximize the potential of carbon sequestration in natural and working lands. Healthy Soils provides incentives for farmers to implement practices like cover cropping and compost while the AMMP program can help curb methane emissions, which must be reduced by 40% to reach the 2045 emissions reduction goal.
The potential is high for natural and working lands solutions in California, and as the report authors find, sufficient and consistent program funding is needed to scale up, accelerate and achieve the maximum carbon sequestration benefits. Additional research is also needed to validate the potential of California-specific carbon sequestration rates. Investing in these programs and research now will also allow the state and researchers to investigate the other complex solutions outlined in the report.