This event was hosted by TABLE on 16 October 2023 and took the format of a panel discussion with:Dr Tara Garnett (director of TABLE);Professor Wim de Vries (Wageningen University & Research);Pauline Chivenge (International Rice Research Institute);Rasmus Einarsson (Swedish University of Agricultural Sciences).

The Amazonian dark earth (terra preta) is not only incredibly fertile but is also a substantial carbon sink. However, whether or not this soil was formed intentionally through indigenous land practice has long been unclear. This paper uses soil analysis and ethnographic observation to demonstrate similarities between ancient and modern dark earth formation by indigenous communities, and to quantify the benefits these practices could have for soil fertility and carbon sequestration.

Improving soil health and soil biological communities through agroecological management approaches will be essential for mitigating the environmental impacts of agricultural intensification in the future. In order to demonstrate some of the values of agroecological practices, this meta-analysis estimates the value of soil biological communities through the earthworms impact on the productivity of global cereal and legume crops.

Soil carbon sequestration involves carbon dioxide being removed from the atmosphere and stored in the soil as soil organic carbon (SOC). This process has been shown to help mitigate climate change; however exactly how SOC forms and persists remains uncertain. This study aims to uncover the role soil microorganisms play in SOC formation, preservation and loss.

A consensus statement on a shared vision of the future for the food system has been published by WWF-UK and co-signed by representatives of several UK organisations, including Pasture for Life, the Soil Association, the Eating Better Alliance and the Food, Farming and Countryside Commission. The statement says that the food system should make space for nature both on farms and in wider landscapes; that farmers should be supported in reducing their use of pesticides and synthetic fertilisers; that regenerative soil management should become the norm; and that technology can play a role in sustainable food production. The statement also criticises intensive livestock production and the marketing of unhealthy ultra-processed foods. It does not call for a reduction in animal product consumption.

This paper critiques the narrative of soil carbon sequestration as a win-win solution offering climate mitigation as well as improving multiple “soil functions” such as fertility, biodiversity and water retention. It argues that accounting for the likely saturation of soil organic carbon over time significantly reduces the estimated potential contribution of soil carbon sequestration to climate mitigation. Furthermore, it finds that the literature does not show a general positive association between soil organic carbon sequestration and improved crop yields - rather, the effects on yields can be positive, neutral or negative depending on the situation.

This report by the Center for International Environmental Law explores a little-known source of plastic pollution: the deliberate addition to soils of pesticides and fertilisers encapsulated in microplastics. This form of agrochemical is often marketed as “controlled release”, with producers arguing that they support sustainable agriculture. The report argues that the intentional use of microplastics in agriculture should be banned on account of the potential for plastics - and the agrochemicals they carry - to accumulate in ecosystems and food supply chains.

This paper summarises what we know about the links between soil pollution and human health, with a focus on cardiovascular disease. The main issues it considers are macroplastics, microplastics, deforestation, pesticides, overfertilisation and heavy metal toxins.