Although agriculture is highly vulnerable to climate change, it is also a significant contributor to the climate crisis. The sector generates approximately one fifth of global greenhouse gas emissions –through unsustainable land use practices, widespread deforestation, high rates of food loss and waste and growing dependence on fossil fuels.
While much of our response to climate change has focused on helping farmers adapt, we also need to mitigate the negative environmental impacts of unsustainable agricultural practices, encourage farmers to adopt more sustainable modes of production and ensure they become an integral part of climate-related solutions.
Healthy soils should be a critical focus of these efforts. Soils play a major role in global climate processes through their regulation of carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) emissions. Soil is a critical carbon reservoir, storing up to four times more carbon than terrestrial vegetation. Sustainable soil management is a cost-effective way to enhance carbon sequestration, while also providing multiple other ecosystem services, including efficient nutrient cycling and increasing soil's water-holding capacity.
But one third of soils globally are degraded, affecting an estimated 3.2 billion people, and this worrying situation requires urgent attention. We need to limit further soil degradation, restore the productivity of soil and stabilize global stores of soil organic carbon.
Protecting healthy soils
Promising practices that can reverse degradation and enhance soil health include crop rotation, continuous soil cover, manure addition and sustainable grazing management. Agricultural production systems that share space with biodiversity are also effective. For instance, the practice of integrating trees into agriculturally productive landscapes – agroforestry – has been a critical focus of WLE's research. This proven intervention enriches soil organic carbon, improves soil nutrient availability and soil fertility, enhances soil microbial dynamics and reduces run-off and erosion.
Realizing these benefits requires improved targeting – ensuring the right interventions are applied in the right locations. Understanding the current health of a given landscape is an important first step. Given the diversity of landscapes, it's also necessary for planners to embrace complexity and develop sampling designs that capture the variability and interaction between key indicators to help build a more thorough understanding of the drivers of degradation. Additional investments in performance analysis are needed, including in above- or below-ground carbon capture, soil health and measures of the ecological integrity of production systems.
A promising innovation supported by WLE is the Land Degradation Surveillance Framework (LDSF), which brings together physical and chemical analysis of the soil itself with above-ground indicators like vegetation cover, tree and shrub biodiversity, historic land use and visible signs of erosion. The LDSF provides a biophysical baseline understanding of soil and ecosystem health at the landscape level and enables monitoring over time as soil either degrades or (ideally) recovers its health under rehabilitation efforts.
Strategic targeting of interventions should also involve local communities. Solutions must be tailored to local conditions (social, biophysical and economic) and also generate multiple benefits – for both the environment and the livelihoods and wellbeing of farmers and their families, who need to feel they have a stake in the outcomes of restoration and soil health improvements.
Finding the right enabling environment
Healthier soils, land restoration and nature-positive agriculture also need to be more strongly integrated into global environmental policies and agreements, including Nationally Determined Contributions (NDCs), where countries signed up the Paris Agreement outline their efforts to reduce emissions and adapt to climate change. Recent discussions on agriculture and soil at COP 26 and the United Nations Food Systems Summit could help.
Additionally, scaling up truly sustainable and regenerative forms of agriculture needs a more abundant source of funds that communities, countries and planners can tap into. Fortunately, there have been some promising developments on this front. The Coalition of Action 4 Soil Health, for instance, is a global partnership that aims to address public and private investment barriers that prevent farmers from adopting healthy soil practices. We are also seeing the emergence of innovative financial mechanisms that could help to plug investment gaps, including the ACORN initiative, managed by Rabobank, which pays farmers to implement climate-mitigating agroforestry practices.
We need to raise our ambitions and recognize that more work needs to be done. On World Soil Day we acknowledge progress but reiterate our call for additional investments in healthy soil so we can protect and nurture this precious resource – and by doing so strengthen our response to the climate crisis.
Thrive blog is a space for independent thought and aims to stimulate discussion among sustainable agriculture researchers and the public. Blogs are facilitated by the CGIAR Research Program on Water, Land and Ecosystems (WLE) but reflect the opinions and information of the authors only and not necessarily those of WLE and its donors or partners.
WLE and partners are supported by CGIAR Trust Fund Contributors, including: ACIAR, DGIS, FCDO, SDC, Sida and others.