Net ecosystem exchange: a paradigm shift for tracking the carbon footprint of land use

The net ecosystem exchange approach offers a number of advantages compared to conventional carbon monitoring approaches

April 27, 2023
The net ecosystem exchange (NEE) approach is a paradigm shift for tracking land-based CO2 sequestration and emissions in agrifood supply chains.

NEE represents the net exchange of CO2 between the atmosphere and the major ecosystem carbon pools: above- and below-ground biomass, soil organic matter, and dead organic matter. NEE is the difference between photosynthesis, plants drawing CO2 out of the atmosphere, and respiration, the ecosystem “breathing” and releasing CO2 into the atmosphere.
Ecosystem carbon balance terms
Why do we need NEE?
Calculating CO2 emissions and sequestration due to biological processes is complex.

An ecosystem is both drawing CO2 out of the atmosphere via photosynthesis and releasing it via respiration, so we need to understand the net difference in those processes. And the rates of these processes differ based on land cover type (crop, forest, etc), region, weather, historical and current land management practices, and more. It gets complicated quickly.

Direct measurements of NEE account for all of the aforementioned variables, making it a great parameter to track productive ecosystems and nature-based solutions in a holistic way.

As an independent parameter, NEE can be used to assess the carbon productivity of fields, farms, and forests. Areas with lower (negative) NEE absorb more carbon from the atmosphere and transform it into agricultural products and natural carbon pools, making this parameter “a primary gauge of ecosystem [carbon] sink strength.” 1

And because the approach accounts for all major carbon pools, it provides a more holistic view on an ecosystem, making it a proxy for ecosystem health and biodiversity.2
Net ecosystem exchange infographic
How can NEE be measured accurately?
There’s a global network of stations that have made continuous, direct measurements of NEE on an hourly basis since the early 1990s using the eddy covariance method. At CarbonSpace, we’ve tuned satellite imagery with this primary data to develop highly accurate, specific models for all major land cover types globally. As a result, you don’t need to have a station in your immediate area to access NEE monitoring.

You can read more about our technology here and access our peer-reviewed paper here.

How does NEE compare to other carbon estimation approaches?
NEE offers a number of advantages compared to conventional carbon monitoring approaches.

Physical methods, such as soil sampling and tree allometry, are expensive, infrequent, and difficult to scale, especially with global and remote suppliers.

Generalized tools, such as calculators based on emissions factors and industry averages, have high uncertainty and significant reserve buffers built in, meaning the estimates are generally conservative. They also don’t capture unique local conditions and management practices. Carbon sequestration could be occurring that these tools won’t account for.

CarbonSpace’s NEE monitoring is remote, scalable, and based on primary data. It’s applicable to all major land cover types in the world (croplands, grasslands, forests, shrublands, and more) and can thus capture the unique performance of practices such as agroforestry, intercropping, restoration, afforestation, and ecosystem corridors.

With this breadth, NEE monitoring provides unrivaled visibility to supply chains and project performance.

Who can benefit from NEE?
Up to 90% of a food & beverage company’s greenhouse gas emissions are Scope 3, or from their supply chain. The agrifood industry is setting ambitious climate targets and working with suppliers to implement climate-smart practices that can not only reduce emissions but sequester CO2 as well. And accurate, scalable, and cost-effective CO2 monitoring is essential to reach these targets.

CarbonSpace’s NEE monitoring enables agrifood companies to:
  • Track and assess global supply chain performance with a unified tool, including the impact of new initiatives and nature-based solutions
  • Understand whole ecosystem health and productivity, rather than only focusing on a single carbon pool
  • Avoid using averages and emissions factors, which don't fully capture local variations and effects of management practices
  • Ensure deforestation free supply chains
  • Track and share climate progress with science-based, primary data

NEE provides a comprehensive understanding of the carbon balance of an ecosystem, taking into account all sources and sinks of CO2, seasonal variations, and land management impacts. It’s the most precise, operative, and cost-effective way to track carbon stock changes.

The NEE approach is essential for the agrifood industry to reach supply chain climate goals.

Monitor your supply chain or nature-based carbon removal projects with primary NEE data:

  1. Joseph C. Restaino, David L. Peterson, Wildfire and fuel treatment effects on forest carbon dynamics in the western United States, Forest Ecology and Management, Volume 303, 2013, Pages 46-60, ISSN 0378-1127,
  2. Geller, G.N. et al. (2017). Remote Sensing for Biodiversity. In: Walters, M., Scholes, R. (eds) The GEO Handbook on Biodiversity Observation Networks. Springer, Cham.

Special thank you to Vitaly Pashkin for his skills creating infographics, including the NEE infographic in this article!