A national carbon farming program at the USDA level would be a tremendous leap forward with regards to incentivizing agricultural practices that can help mitigate climate change. However, the current primary focus on no-till and cover cropping is narrow in scope. While cover cropping is an extremely important and impactful agricultural practice, it is merely a part of a larger system needed to regenerate healthy soils on a nationwide basis.

Designing a Whole-System, Outcome-Based Approach

Rather than focus on single farming practice benefits, designing a whole-system approach will create synergy between practices and enterprises, and bring about significant soil carbon sequestration, GHG emissions reductions, and other ecological co-benefits. Fortunately, there are myriad other management interventions that the USDA can fold into their strategy to ensure that the agriculture sector maximizes its full potential in the fight against climate change.

In order for the Biden Administration to ensure that money spent on climate-related USDA incentive programs is supporting real net impact, these programs must be spurred by practice-based incentives that are holistic in scope and supported by comprehensive outcomes-based assessments.

Furthermore, these outcomes must be quantified by a hybrid approach that includes:

• Ground-basedmonitoring,
• Remotesensing,
• Process-basedmodeling

 

In addition, outcomes must be assessed comprehensively, within the context of whole systems, throughout supply chains, and across all GHGs (including methane and nitrous oxide) and emissions scopes.

Integrating cover crops into a row crop system can:

• Increase levels of soil organic carbon,
• Increasesoilwaterinfiltrationandholdingcapacity,
• Reducetheneedforsyntheticfertilizers.

 

However, the system where cover crops are adopted will dictate how these benefits are achieved.

Limitations of Current Soil Carbon Measurement Standards

For example, in annual row-crop systems that use conservation tillage and chemical no-till practices, research has demonstrated that gains in soil organic carbon in the top 20-30 cm of soil in these systems can be offset by losses in deeper layers, and therefore these practices are likely not as effective as previously understood (1,2).

It is now clear that the ability to monitor and model changes in SOC deeper in the soil profile is essential to assessing real outcomes. Thus, having the right kind of monitoring, reporting and verification (MRV) strategy that can adequately and comprehensively assess the ecological, social, and economic impacts of a comprehensive, sector-wide incentive program is of the utmost importance.

Traditionally, carbon offset methodologies for the agriculture sector have relied solely on process-based modeling, the quantification standard in data-poor environments. However, process-based models are only as good as the ground truth data used to develop them.

The most widely used modeling tool to-date is the USDA’s COMET-Farm tool, which is designed to estimate GHG emissions and sequestration at field scale, based on management practices. While this tool has been developed over the course of decades, with data from dozens of research projects throughout the Midwest and Great Plains, it lacks the sophistication to adequately quantify outcomes.

The two most limiting factors of this particular model are its inability to estimate SOC sequestration below 20 centimeters (8 inches), and its inability to quantify the impacts of a broad spectrum of management practices related to cover cropping, grazing, and manure management (3). As a result, necessary practice and system innovation are not supported by these tools. Furthermore, there is a larger limitation with models in general, which is that their output is focused at field scale, and therefore excludes upstream and downstream impact.

In our opinion, the Biden Administration will face grave political consequences and fail to achieve its urgently needed climate goals in agriculture if it follows through with a narrowly-defined incentive program supported by inadequate quantification infrastructure.

Direct measurement of outcomes in an incentive program should be the holy grail.

The greatest challenge to direct measurement is decreasing the sampling burden enough while still capturing spatial and climatic variability. As satellite and ground-based sensor technology advances, the potential for adequately quantifying variability to support cost-effective sample stratification is significant (4,5).

In addition, as the development of process-based modeling must always be an ongoing project, satellite and ground-based sensors can continuously feed necessary ground truth to further advance the accuracy and sophistication of models, and to automate the model input process.

Proper Funding for Soil Health Measurement Technology is Key to Program Success

It is essential that the Biden Administration allocate funding to advance the state of the art of NASA’s Earth Observing System satellites, and to engage in public private partnerships with the world’s best satellite data providers, with the goal of enhancing our ability to leverage remote sensing as a means to monitor the ecological impacts of the agriculture sector. Note: Further efforts to develop and deploy earth observing satellite platforms should be focused on:

• Advancing sensor technology,
• Enhancing spatial and temporal resolution of satellite data,
• Making data publicly available

 

This will allow for the necessary access to correlative datasets to further develop accurate monitoring platforms.

It is also essential that the USDA support the strategic deployment of sector-wide ground-based sensors, monitoring sites and stations across crop fields, CAFO facilities, and at points throughout critical watersheds facing immense pollution pressure (such as the Mississippi and Chesapeake Bay). This will serve to support the development of remote sensing and process-based modeling tools, and also to provide a critical feed-back system that can allow USDA program officials to conduct regular impact assessments based on directly-observed outcomes, and to more rapidly recalibrate the approach to management recommendations.

The current state of ground-based sensor technology, including in-situ soil and water monitoring systems, is such that national-scale monitoring can be rolled out with the necessary degree of standardization.

When considering the environmental impact of the agriculture sector in the United States, it is important to consider the extent to which agricultural enterprises have become consolidated, dis-integrated and specialized compared to a century ago. Therefore the sector as a whole should be considered as one large system, with one type of enterprise (i.e. grain) providing inputs that feed into another (i.e. livestock). In this holistic context, it is clear that the impact of a single management intervention in a certain sub-sector, such as cover-cropping, will be much less in the aggregate (or even fully offset) when measured against the impacts of other downstream sub-sectors, such as CAFO methane emissions.

Therefore, fully functioning incentive programs would be comprehensive and sector-wide, would facilitate GHG emissions reductions and atmospheric drawdown across supply chains, and would consider and quantify not only GHG emissions reductions and SOC sequestration, but also other forms of ecological impact related to water (6) and biodiversity, as well economic and social impact.

Expand and Fully Fund Conservation Programs – CRP and Regenerative Grazing

The expansion of existing USDA programs can also go a long way towards supporting a comprehensive carbon farming program, if high-level principles of regenerative organic agriculture are considered. These principles include biodiversity, tillage reduction, annual-perennial crop rotations, animal integration, aerobic manure management, natural fertility inputs, and protection of waterways.

One of the largest pieces of low-hanging fruit with regard to existing programs is the Conservation Reserve Program (CRP). There are two simple ways in which CRP can support carbon farming in the U.S.:

1) Expanding the CRP budget to increase enrolled acres, and

2) Developing a grazing program on enrolled CRP land that establishes a supply chain between cow-calf operations grazing on public and private land in the western U.S., and CRP grazing permittees, which will have the effect of diverting animals from feedlots to pasture, which will increase domestic production of grass-fed beef, a market for which there is significant demand in this country that we are not currently meeting domestically.

This will also significantly decrease GHG emissions associated with feedlot production and crop production. In order to support a CRP grazing program, funding for fencing and water infrastructure could be met through expanding the Environmental Quality Incentives Program (EQIP) budget. In addition, EQIP funding for cover crop seed and planting equipment, and composting infrastructure (7), will go a long way towards further reducing methane and nitrous oxide emissions associated with crop and livestock production. Direct coordination with USDA and the Bureau of Land Management and the US Forest Service, in the form of rangeland management and rangeland health assessments, is also essential to supporting a national carbon farming program.

Healthy rangeland is a tremendous carbon sink, and presents perhaps one of the greatest opportunities in this country to sequester carbon in soils. The USDA must work with BLM and USFS to improve rangeland health assessments using satellite and ground-based monitoring (8), and to provide technical and financial support for improved rangeland management. This kind of monitoring approach will provide a comprehensive geospatial feedback mechanism that can help pinpoint best grazing management practices and support data-driven implementation.

The Biden Administration has a tremendous opportunity to deploy a robust carbon farming program across the United States, and can leverage many existing USDA programs in support of its goals. However, pains must be taken to ensure that the scope of such a program is sector-wide. This will ensure the full spectrum of opportunities to reduce emissions and sequester atmospheric carbon dioxide are on the table, so as to avoid perceptions of greenwashing and industry placation. Additional pains must be taken to include in this program the farmers and ranchers who have already taken financial risks by adopting and implementing best management practices absent any robust federal program to-date.

 

Matthew Sheffer is the Managing Director at Hudson Carbon.

References:

1.)  No-till and carbon stocks: Is deep soil sampling necessary? Insights from long-term experiments – Humberto Blanco-Canqui a, *, Charles Shapiro a, Paul Jasa b, Javed Iqbal a
https://doi.org/10.1016/j.still.2020.104840

2.)  Tillage and soil carbon sequestration—What do we really know? – John M. Baker a,b,*, Tyson E. Ochsner a,b, Rodney T. Venterea a,b, Timothy J. Griffis b
https://doi.org/10.1016/j.agee.2006.05.014

3.)  Comparison of COMET-Farm Model Outputs to Long-Term Soil Carbon Data at Stone House Farm – Matthew Sheffer, Mike Howardhttps://docs.google.com/document/d/1dVx_ICmMSKeiELIR00v6JHsJoBxABLu_WDyl0Chwick/edit?usp=sharing

4.)  A New Index for Remote Sensing of Soil Organic Carbon Based Solely on Visible Wavelengths – Evan A. Thaler* ,Isaac j.Larsen, Qian Yuhttps://doi.org/10.2136/sssaj2018.09.0318

5.)  Optimizing Stratification and Allocation for Design-Based Estimation of Spatial Means Using Predictions with Error

– J. J. De Gruitjter* B. Minasny A. B. McBratney

6.)  https://doi.org/10.1093/jssam/smu024Understanding the temporal behavior of crops using Sentinel-1 and Sentinel-2-like data for agricultural applications – Amanda Veloso ⁎,1, Stéphane Mermoz, Alexandre Bouvet, Thuy Le Toan, Milena Planells, Jean-François Dejoux, Eric Ceschia
https://doi.org/10.1016/j.rse.2017.07.015

7.)  Compost: Enhancing the Value of Manure; An assessment of the environmental, economic, regulatory, and policy opportunities of increasing the market for manure compost – Sustainable Conservation, 2017 https://suscon.org/pdfs/compostreport.pdf

8.) Beyond Inventories: Emergence of a New Era in Rangeland Monitoring – Matthew O. Jones , David E. Naugle , Dirac Twidwell , Daniel R. Uden , Jeremy D. Maestas , Brady W. Allreda
https://doi.org/10.1016/j.rama.2020.06.009