Ecosystem Carbon Management: A Paradigm Shift
What is Ecosystem Carbon Management?
Ecosystem carbon management is the intentional management of ecosystems to enhance and maintain carbon storage.
“Ecosystem carbon management,” a new concept developed by CATF, aims to reflect and value various strategies for managing ecosystems to enhance carbon sequestration and storage. The concept expands the scope beyond traditional nature conservation and restoration for climate change mitigation, typically referred to as ‘nature-based climate solutions,’ to include new and emerging strategies that harness the power of ecosystems for managing carbon.
Ecosystem carbon management involves multiple pathways, including conventional biological approaches to organic carbon storage in trees and soils, novel approaches that introduce carbon rich biomass-based materials to ecosystems for long-term storage such as biomass burial and biochar, engineered pathways like enhanced rock weathering that accelerate geochemical carbon storage and rely on existing ecosystem processes such as weathering and mineral transport, and approaches that use biomass to capture carbon for permanent storage.
Activities considered ecosystem carbon management may avoid and reduce ongoing emissions from the land sector, serve to remove additional carbon from the atmosphere, or in many cases, do both at the same time.
Ecosystem carbon management can occur in various ecosystems including land ecosystems such as forests, grasslands, and agricultural systems; as well as aquatic and marine ecosystems such as rivers, coastal waters, and open oceans. Ecosystems managed for carbon may be urban or rural, working or conserved lands, and degraded or pristine. Ecosystem carbon management also recognizes the potential for improving climate outcomes and reducing risks of reversal by managing systems at large scales and over long time periods.
Why is Ecosystem Carbon Management Important?
The full suite of ecosystems and ecosystem carbon management approaches are critical tools in the climate mitigation toolbox.
When undertaken with rigor, there is enormous near-term mitigation potential in conventional ecosystem carbon management activities, such as improved forestry and agricultural practices that protect and enhance biological carbon capture and storage. These activities can also have associated benefits for enhancing ecosystem resilience to ongoing climate change, protecting biodiversity, and maintaining livelihoods worldwide.
Significant technical potential also exists to further harness the power of photosynthesis, the single largest flux of carbon between the atmosphere and coupled human-land systems, to capture and permanently store carbon out of the atmosphere. Plant-derived materials that contain captured atmospheric carbon can be used in innovative ways to create useful long-lived products and develop long-term storage approaches that keep carbon out of the atmosphere for centuries to millennia. There is also rapid innovation in engineering systems that rely on the connectivity of ecosystems and the concentration of atmospheric carbon into plants and soils to accelerate natural weathering processes that can fix carbon into minerals for millennia.
Existing and emerging approaches to increasing carbon storage in ecosystems can help keep the global carbon cycle, and its feedbacks into the water cycle, nutrient cycles, and climate system, in check as countries decarbonize.
What are the Different Approaches to Ecosystem Carbon Management?
Ecosystem carbon management can broadly be classified into ‘conventional’ approaches that store organic carbon in ecosystem trees and soils, and ‘novel’ approaches which leverage ecosystem functions with technology to store carbon for very long periods of time.
Conventional ecosystem carbon management approaches are available at scale today but have a significant risk of reversal, meaning that carbon stored away in trees and soils could be remitted to the atmosphere through, for example, deforestation or fire. Many novel approaches can store carbon for thousands of years but are not yet technologically mature enough for deployment at scale. There is therefore a need to balance responsible deployment and appropriate use of high-quality conventional ecosystem carbon management options available today while simultaneously taking action to ensure that more permanent novel approaches can develop at scale as quickly as possible.
Conventional approaches
Conventional biological approaches to ecosystem carbon management contribute approximately two gigatons of carbon removal per year to climate mitigation today. This entails a wide range of management activities, including but not limited to:
- Sustainable forest management for ongoing timber harvest
- Expansion of forest area through reforestation (replacing forests that have been cleared) and afforestation (planting forests where they did not previously exist)
- Protection and conservation of existing forests
- Agricultural practices that maintain and/or increase soil carbon content, like cover and rotational cropping systems
- Introducing tree cover into agricultural production and grazing systems
- Conservation and restoration of coastal and inland wetland ecosystems
Ecosystem carbon management through these conventional approaches must be deployed in ways that move beyond business-as-usual management to be additional and have real climate impact. While demonstrating that conventional nature-based strategies are an added benefit has been and remains a challenge, quantification and monitoring approaches that leverage cutting edge science and data resources are under development and may enable carbon management at large ecosystem scales.
Novel approaches
There is a large and growing suite of new technological approaches to storing carbon in ecosystems for centuries to millennia. These include utilizing plant-derived biomass processed to increase durability, like biochar, or using the vast extent of natural and managed ecosystems to bury or sink carbon rich materials and thus keep it out of the atmosphere. Research is ongoing to understand how to accelerate processes, such as rock weathering and balancing the ocean bicarbonate cycle, to store atmospheric carbon dioxide for millennia. This includes applying crushed minerals to agricultural fields, forests, wetlands, or other ecosystems to speed the weathering process, transport captured carbon dissolved in water through streams and rivers to the coast, and ultimately store captured carbon in the ocean in mineral form. Other approaches look to increase mineral carbon storage in the ocean by increasing alkalinity of ocean waters directly, which can shift the balance of the ocean carbon cycle and lead to drawdown of atmospheric carbon dioxide through increased rates of ocean uptake. These kinds of novel open-systems approaches are at the forefront of scientific and engineering exploration. Many questions remain about how to implement these approaches, but the climate mitigation potential may be significant.
Examples of novel approaches, which are still emerging, include:
- Enhanced rock weathering
- Ocean alkalinity enhancement
- Burial of plant-derived biomass carbon
- Sinking plant-derived biomass deep into the ocean
- Biochar production and storage in ecosystems and products
Advancing Ecosystem Carbon Management
As novel technologies for ecosystem carbon management emerge, appropriate policy structures for governing and valuing carbon removal and storage through ecosystem carbon management must be developed to ensure there are both financial incentives for deployment and appropriate guidelines and safeguards to ensure these novel approaches have real climate benefit and do not harm people or the environment.
Adopting “ecosystem carbon management” as a concept will help encourage innovation and value the full expanse of biological, geochemical, and technological methods for enhancing carbon sequestration and storage that have emerged since the advent of the term “nature-based solutions.” Appropriately identifying a range of ecosystem carbon management approaches will enable targeted efforts to raise the bar on the tools, scales, appropriate uses and climate outcomes for both people and the environment.
Learn more about CATF’s leading work on ecosystem carbon management and reach out with questions at [email protected]