As we approach a point for urgent action to deal with climate change, the reality of ‘business as usual’ is now being questioned. This, together with the fact that natural resources are being depleted, means that all industries need to change, and the fashion industry is no exception.

Soil is now under the spotlight in the UK and to date, it has been an undervalued resource that is essential to all life. With this, the link between the fashion industry and soil is just being realised.

Although in theory soil is renewable, it is now considered in practice as more of a non-renewable resource due to the fact that we are essentially mining the soil globally and depleting it much faster than the very slow rate of natural generation. The significance the soil holds in terms of sustainability is vast and prioritising its health can be linked to working towards a number of the UN’s Sustainable Development Goals.

“growing and harvesting cotton accounts for 3.6-4.3% of global GHG emissions from agriculture or 0.4% of overall global emissions”

The soil is not only used as a medium for growing food and fibre, but it also filters, recycles and stores water, moderates the climate and supports a myriad of life within and above it. Soil is also the second largest natural carbon sink after oceans in its capacity to store carbon, and so is one of our greatest tools for mitigating climate change. The success of all of these functions are, however, greatly dependent on the quality and management of the soil.

The scale of soil degradation

As much as a third of the planet’s land is now severely degraded according to the UN, causing drought and loss in soil fertility. To improve soil health, 110 countries joined a global target to reach land degradation neutrality by 2030 as an international call for action. This means engagement by all industries to adopt soil conservation practices.

Cotton is one of the world’s most grown crops, occupying 2.5% of all arable land. This represents about 35 million hectares of land. The growing and harvesting of this crop account for 3.6-4.3% of global agriculture’s GHG emissions, or 0.4% of overall global emissions. This is huge. And given the significance that it has in the textiles industry, it is imperative that the impacts of growing cotton are accounted for.

Soil erosion

Cotton is mainly grown in arid or semi arid climates, and given the nature of the dry land this means that the soil is vulnerable to erosion by water and wind, which is exacerbated by tillage. Arguably, erosion of topsoil and loss of organic matter are the main sustainability issues linked to cotton. In the long term, the loss of topsoil and soil degradation affects crop yields as well as impacting the environment. Erosion is an inherent natural problem in arid areas but it is exaggerated by climate change. Additionally, farm practices such as over-tilling, irrigation, and leaving the land bare in extreme weather, also speed up the erosion process rapidly. The subtropical regions where cotton is grown is especially susceptible to water erosion, as the hot dry season bakes the soil dry, and is then followed by heavy, intense rain which causes surface runoff that sweeps the top soil away. Additionally, many cotton growing regions are also susceptible to wind erosion and dust storms. Degradation is often incremental, and because cotton is a tolerant crop, the impacts on soil quality may go largely unnoticed until crop yields start to drop. The true global extent of soil erosion from growing cotton is unknown, however on average, 24% of global arable land is eroded, with the annual economic loss of $8 billion from crop yield and increased water use.

The impacts on water and air

Surface runoff from rain and irrigation displaces soil particles that can cause pollution, eutrophication and sedimentation in waterways. The effects can be made worse if the runoff contains high amounts of synthetic and organic fertilisers. Fertilisers are expensive and are known to exhaust the soil of nutrients. In some cases within cotton farming, this has promoted abandoning depleted land to expand into new areas, resulting in further knock on effects including loss of natural habitats.

It has been estimated that the world’s cultivated soils have lost between 25 to 75 percent of their original carbon stock, releasing CO2 into the atmosphere and contributing to the greenhouse effect. Keeping carbon in the soil is crucial, and increasingly it is now realised that soil offers a huge opportunity to actually sequester and drawdown CO2 from the atmosphere, mitigating the greenhouse effect.

The impacts on soil biology

A further impact of cotton farming is the potential damage from using GM cotton varieties. Bt cotton uses the bacillus thuringiensis toxin as an artificial systemic control of pests. Recent research has been shown that the toxin affects the symbiotic relationship between the cotton plant and arbuscular mycorrhizal fungi in the soil. Fungi are essential in the exchange of nutrients and water that take place between the plant and the soil. This has an effect on soil ecosystems that are key for crop health, soil health and structure, and can create further soil degradation. Bt seed now monopolises all major cotton growing countries.

Cotton is sensitive to weed competition and susceptible to insect attack, which consequently leads to the extensive use of chemical herbicides and insecticides. Cotton currently uses 16% of the world’s pesticides which truly highlights the scale of use. Persistent use can lead to soil contamination, polluted surface runoff and groundwater contamination. It can also kill soil microorganisms, fauna and non-targeted life such as worms and bees. Dangerous chemicals such as Endosulfan and Aldicarb that have been withdrawn in many parts of the world are still reported as being used on cotton.

The impacts of irrigation

In some cotton growing areas such as Australia, India and Pakistan, the irrigation of cotton can lead to salinisation of the soils. This is due to drylands and high evapotranspiration rates. The increased concentration of salt in the soil affects the roots of the cotton plant, decreases the nutritional balance and affects soil structure. This in turn increases the risk of erosion and affects crop yields. An estimated 20% of cultivated land and 33% of irrigated agricultural land are impacted by high salinity.

Regenerative agriculture

There is no doubt that alternative farm management approaches are needed that focus on the health of the soil. With a few different more sustainable systems already being practiced, such as organic farming and the Better Cotton Initiative (BCI), there is one interesting approach that is aiming to go beyond sustainability by regenerating the soil. This is called regenerative agriculture.

Regenerative agriculture is a holistic approach that promotes the restoration and regeneration of the land through the use of beneficial farming practices that build organic matter, capture carbon and contribute to healthy ecosystems. This is achieved by minimal tillage, use of diverse cover crops, novel grazing practices, use of composts (organic materials and manure) and little to no use of agrochemicals. These practices build resilience to drought, soil erosion and naturally increases agricultural productivity. Water retention is increased, which can cut down the need for excessive irrigation. Minimum or no tillage is used to decrease soil erosion and limit carbon loss – a practice found to perform best in dry climates. What’s more, is that reduced tillage utilises the symbiotic relationship between plants and the soil to draw carbon from the atmosphere back into the soil, thus increasing carbon levels in the soil. This, done on a large scale, is auspicious in mitigating climate change, and according to the Rodale Institute, arable soil has the ability and capacity to sequester the global annual production of global greenhouse gas emissions.

Regenerative agriculture is an established farming approach that is proven to dramatically decrease soil erosion and greatly increase the sustainability of the crop/s being grown. It has been practiced for a long time on a wide range of food crops such as wheat and maize, but the use on non-food crops is just emerging. The principles can be used with all the fibres used in textiles. However, as with all practices there are some risks. Within no-till there are risks of compaction due to the use of heavy machinery and where soil is not regularly loosened, as well as the overuse of chemical herbicides – which are used to control weeds as a replacement to ploughing which buries weeds. Similarly, some believe that to receive the full benefits of regenerative agriculture, all practices need to be organic and it is contradictory to be using agrochemicals in such a holistic system.

“cotton, as one of the biggest crops in the world, has to be a part of the global effort to improve the soil through sustainable farming practices”

The movement of using regenerative agriculture for cotton and other fibres is relatively very small, and so the extent of its success is unknown.

The relationship between soil and the fashion industry

The importance of soil health is indisputable in mitigating the impacts of climate change and reversing soil degradation. Cotton, as one of the biggest crops in the world, has to be a part of the global effort to improve the soil through sustainable farming practices. Fashion retailers and the public need to be a part of the conversation and take responsibility for the impact that is happening on behalf of it. The fashion revolution starts from the ground up.

“the fashion revolution starts from the ground up”

Some companies are starting to develop branding of garments such as jeans and t-shirts that use regenerative agriculture. This is an emerging market. However, in order to avoid ‘greenwashing’ and to make certain that practices are sustainable, some organisations have decided to test the soil to demonstrate improvement.

With this, it is key to use metrics to define performance indicators, so that data collection has a focus, and progress (if any) can be monitored. Data collection is crucial in understanding whether any new techniques used are having a positive effect. This can then be communicated throughout the company, to customers and to other retailers or suppliers to work together in becoming more sustainable. This takes a paradigm shift throughout the industry including farmers. And it is critical for the fashion industry to support their suppliers right down to the bottom of the supply chain. With this, priority can be placed in data collection and emphasising increasing soil health by investing in climate beneficial systems.