There is growing evidence that carbon offsetting is not an effective carbon emissions reduction tool, as presented in our recent assessment. Insetting, which involves carbon sequestration (removal) and abatement (avoiding or reducing emissions), is gaining momentum as an alternative. As a holistic strategy implemented within an organisation’s value chain, insetting can provide greater transparency and control, focusing on creating positive impacts for communities and ecosystems.¹

Insetting is considered a viable alternative to offsetting and within that, one lever is Regenerative Agriculture (RA); but how effective is it at sequestering carbon emissions? How is this measured, and how are brands using RA as an emissions reduction tool to help hit their Science-Based Targets (SBTs)?²

Regenerative Agriculture is a practice that involves enhancing soil health and thereby sequestration of carbon from the atmosphere through various means, including cropping and livestock practices. Borrowing from the ‘farm-to-table’ concept in the food industry, a ‘farm-to-closet’ idea is being adopted by some fashion brands as a strategy for insetting to help fulfil their climate commitments.

Fashion’s fibre production phase is one of the main drivers of the industry’s global pollution impacts including climate change, freshwater withdrawal, ecosystem quality and human health.³ The cultivation of natural and animal fibres is connected to the land due to the dependence on natural resources. Therefore, the potential for impact is also foreseeable. This is because RA practices are focused on ‘replenishment’ and have been proven to absorb and facilitate the reduction of greenhouse gas emissions (GHG), which the industry must urgently achieve.⁴ The SBTis have also identified RA as a strategy for GHG reduction.⁵

Regenerative Agriculture

Although RA doesn’t have a universal definition, it is a holistic method of farming that emphasises the connection between farming systems and the broader ecological system.⁶ RA supports soil health to optimally sequester carbon from the atmosphere and build ecosystem resilience. Soil is a natural ‘carbon sink’, however, global soil carbon stocks have declined over time.⁷ RA aims to help restore this and increase water availability and quality, while promoting biodiversity that could ultimately lead to higher yields and a more sustainable agricultural system.

Implementation and measurement

As an insetting strategy, RA requires collaboration and intervention at the farm level, and finance is a critical component of integrating RA. Otherwise, farmers face significant challenges in implementing and maintaining regenerative farming systems due to the required up-front capital investment and the introduction of a completely new set of maintenance and monitoring methods, as opposed to the traditional industrial methods they are accustomed to. This financial risk is believed to be a major barrier to farmers transitioning to regenerative agriculture methods.⁸

Due to the wide range of co-benefits that regenerative processes provide and that the approach is holistic, measuring and modelling these benefits presents an ongoing challenge.⁹ This is exacerbated by the evolving nature of the ‘new social science understanding’ of carbon sequestration that can affect the mathematical assumptions underpinning computer modelling for calculation.¹⁰ For example, current approaches to measuring soil carbon impacts combine old and new techniques. Traditional methods involve physically sampling soil and measuring the carbon content in a laboratory, but the depth at which samples are taken, for example, can drastically impact the accuracy of results. As deeper sampling requires more work and expense, the recommended depth for sampling is typically 15 centimetres. However, recent research has found that reduced tillage’s effects on soil carbon are typically not apparent at depths of less than 30 centimetres, posing challenges to accurately assessing the amount of carbon absorbed and therefore accountable within insetting practices.¹¹ 

Several brands, including Allbirds, PANGAIA, and Reformation, have recently invested in regenerative farming initiatives, not least because the carbon sequestration potential has been proven scientifically.  Currently, most brands engaged in such initiatives are running pilots to produce small quantities of ‘regenerative fibres’. However, there is a lack of data available publically to demonstrate the levels of carbon sequestration attributable to such fibres.

Effectiveness

There is a growing body of research that RA practices can sequester carbon, but also ongoing debate about how much carbon can be stored and for how long. This is because the amount of carbon that can be held in soil is finite and interdependent on biomass. Further, for capture benefits must be maintained a farm must maintain regenerative methods – if it returns to tilling (regular turning over of the soil) for example, the carbon sequestered could be re-emitted. Therefore, RA practices must be long-term to ensure environmental benefits are sustained.

For additional context, a 2021 study published in the journal Nature reviewed over 100 experiments and found that the storage potential of soil may have been overestimated.¹² It found that when exposed to rising Co2 an increase in plant growth (biomass) resulted in a relative decrease in soil carbon storage. The hypothesis had been that as biomass growth increased, soil carbon would increase in tandem, but this was not the case.

The context of this study is outside of industrial agriculture, however, it demonstrates a complex relationship between the growth of plant matter and the ability of soils to store carbon. Ultimately, it debunks any belief that growing more plants and trees leads to more carbon storage in the long term. This is because increased plant growth requires soil nutrients that when ‘metabolised’ release Co2 themselves. Therefore, plants re-release carbon more readily than soil does (in natural grasslands, for example).¹³ These findings point to the complexity of growing fibre crops to optimise and maintain carbon sequestration levels in the consistent and predictable manner required to use them as evidence of absolute emissions reductions. It also points to further flaws in the notion that planting more trees has a linear and predictable relationship with emissions reductions (see our Offsetting piece for more on that).

While RA may be an effective strategy for insetting and a tool for carbon sequestration with multiple co-benefits (like improving biodiversity, water quality and farmer/grower livelihoods), its effectiveness in reducing emissions at the levels required by the fashion sector is not yet quantified. While sequestration is important, abatement is essential, and brands considering regenerative agriculture should be aware of the limitations and potential re-release of captured carbon.

As geologist David Montgomery states:

“Putting more carbon in the soil will buy us some time. But if we continue to burn fossil fuels, once we fill up the soil with the carbon, all we have done is delay things a bit.”¹⁴