Implementing the Soil Enrichment Protocol at Scale: Opportunities for an Agricultural Carbon Market

Abstract

High-quality agricultural carbon credits that incentivize regenerative practices can help address climate change through greenhouse gas (GHG) abatement and CO2 sequestration. Generating large volumes of such credits requires rigorous crediting methodologies. The Soil Enrichment Protocol (SEP) by the Climate Action Reserve (CAR) aims to unlock this type of crediting potential. The SEP includes new expert-driven standards for validating the use of soil biogeochemical modeling to generate credits. Technical experts at Indigo Ag participated in the SEP working group and are supporting implementation of the first project, CAR 1459_RP1, on hundreds of thousands of acres in the US. The authors share their thoughts on new approaches enabled by the SEP as both contributors to the theory behind and practitioners of these approaches. The SEP enables scalable, high-quality credits through four main advances: (1) allowing flexibility in the use of biogeochemical models that meet explicit performance requirements, (2) enabling a new approach to field-level, modeled baselines, (3) supporting a hybrid approach of credit generation using both soil measurement and modeling, and (4) requiring a new type of credit uncertainty quantification that accounts for multiple sources of uncertainty. Together these advances support agricultural credit quantification that enables payments to offset transitional costs for growers, at large enough scales to create a robust market, with a level of rigor that ensures any credited emission reductions have real climate impact. Innovations in soil analyses, advances in research, and improvements in data collection could further improve the potential for agricultural carbon credits to scale.

Amish and Non-Amish Farmer Perspectives on Climate Change Causes, Effects, and Adaptation Strategies

“…For example, private sector sources of information, such as farm service providers and cooperatives, have a growing influence on farm decision-making over public sector sources of information, such as extension [48][49][50][51]. An increasing number of agricultural cooperatives and other private enterprises are working on "carbon farming" initiatives, which allow growers to sell carbon credits for using cover crops and no-till strategies to sequester carbon in soils [52][53][54][55]. While such opportunities to receive payments for practicing climate-smart agriculture are increasingly available to growers throughout the Midwest, future work should assess how open Amish farmers are to participation.…”

Understanding the value of and reasoning behind farmer adoption of carbon centric practices

“…In the US, voluntary initiatives like the Climate Action Reserve aim to register projects in agricultural lands seeking C credits that would be assessed using protocols devised by a commercial entity (Oldfield et al, 2021). Importantly, sampling requirements for verification purposes are left up to the verifier (Climate Action Reserve, 2020; Jackson Hammond et al, 2021). Given the fluidity and hype in this arena, farmers are rightly asking about transaction costs and the veracity of claims as they wonder how to engage with markets and weigh in on policy.…”

A simple soil mass correction for a more accurate determination of soil carbon stock changes

“…These rely on soil sampling, modeling, or a hybrid approach with modeling, sampling, and remote sensing 4 , 6 . Protocols are trending towards a hybrid MRV approach based on SOC modeling and using data from samples taken prior to a management change and periodic re-sampling afterwards (e.g., 5 years) to re-calibrate model estimates and scale MRV 6 , 7 . The desire to reduce the number of soil samples and their processing and analysis stems from the current small margins between the revenue generated from the sales of carbon credits and the cost of sampling and analysis to adequately confirm changes in SOC stocks 8 .…”