World Soil Day

When COP26 concluded in Glasgow, Scotland participants echoed the urgency to limit global warming to below 2°C, ideally below 1.5°C. To achieve this, emissions reductions would need to be supported by all available options to mitigate climate risks. Besides its many functions that support life, soil stores carbon in the form of organic matter and minerals. This carbon sequestration, measured in the form of Soil Organic Carbon (SOC), makes soils the planet’s largest carbon sink on land. Sustainable land and soil management practices hold the potential to offset increasing atmospheric concentration of CO2 and reduce climate vulnerability while ensuring food security for the world.

Soil, a vital part of nature, is the bedrock of our food systems, the forests, grasslands, and all life on land. Besides food and living space, we depend on the humble soil for a range of ecosystem services, from water purification to regulation of our local climates. Despite its critical role in supporting food and agriculture, the health of soil and land resources call for our attention – for our daily bread, the life around us, and the future of generations to come. Scientific observations and studies carried out by several organizations have highlighted the continued decline in the quality of soil.

Some facts on soil degradation

Soil erosion due to loss of forests and vegetative cover, the decline in soil quality (breaking down of soil structure and nutrient loss in the soil) due to unsustainable agricultural practices, drastic changes in land use, and urbanization have emerged among the primary drivers of soil degradation, as per a study by the International Panel on Climate Change (IPCC). 

This degradation has led to a drastic loss of the organic and carbon contents of the soil, essential for supporting the growth of crops and life on land. 

Soil erosion due to loss of forests and vegetative cover, the decline in soil quality (breaking down of soil structure and nutrient loss in the soil) due to unsustainable agricultural practices, drastic changes in land use, and urbanization have emerged among the primary drivers of soil degradation, as per a study by the International Panel on Climate Change (IPCC). 

This degradation has led to a drastic loss of the organic and carbon contents of the soil, essential for supporting the growth of crops and life on land. 

According to the World Wildlife Foundation, our Earth has lost half of its topsoil in the last 150 years. Degradation and decline in soil quality are emphasized even more when we look at the lost agricultural productivity and carbon sequestration – built up over decades. According to the World Wildlife Foundation, our earth has lost half of its topsoil in the last 150 years. Degradation and decline in soil quality are emphasized even more when we look at the lost agricultural productivity and carbon sequestration – built up over decades.

Degradation of soils worsens climate change

The loss of soil and its carbon content is directly linked to climate change – a result of the increase in atmospheric CO2. Erratic weather patterns linked to climate change are projected to give rise to drought-like conditions and erosion of the fertile topsoil from excessive downpours. Climate change could also aggravate soil aridity – a result of higher evaporation due to increased temperatures. 

Loss of SOC due to changes in land use and deforestation accounts for almost a third of the total increase in atmospheric CO2, the remaining two-thirds coming from the burning of fossil fuels. The organic matter (including living organisms and dead plant material) and carbonate minerals present in the soil make up the carbon content in the soil. 

This quality to store carbon makes soils the largest carbon pools on land. Soils, therefore, are vital in the fight against climate change.

Healthy soils are important for climate action & indispensable for the future of food

According to a study by Nature, of all the carbon sequestered in terrestrial ecosystems, nearly 80% of it is found in soil. The International Union for Conservation of Nature (IUCN) estimates that a mere increase in the soil carbon content by 1% in the top meter of soils would offset the annual anthropogenic CO2 emissions from the burning of fossil fuels. The potential role of SOC in emissions reduction and mitigation is further highlighted by initiatives such as the French 4 per 1000 Initiative which champions for an annual increase of organic carbon in soils of 0.4%. 

With the world set on tight deadlines to achieve net-zero emissions, it is imperative to identify and grab hold of all possible mitigation options. What makes investing in sustainable soil management even more attractive are the several co-benefits of healthy soils.

The value of this natural resource is best captured by the agricultural adage that says, “the tiny animals that live below the surface of a healthy pasture weigh more than the cows grazing above it”.

In her book, “Bringing a Garden to Life”, author Carol Williams elaborates further on the complex workings of the underground soil ecosystem. Soil is composed of biotic material such as earthworms, fungi, bacteria, and numerous other microorganisms and plant matter, all of which work together as a single symbiotic system. Changing and growing over time, requiring air, water, and food (nutrients from plants and animals) to stay healthy, soils are even considered a living ecosystem. Even the word “human” is derived from the Latin word “humus”, meaning earth or ground, and the living matter in the soil. 

Besides supporting all life on land, healthy soils have multiple co-benefits such as increased crop yields, climate resilience, reduced erosion, reduced loss of forests, and increased biodiversity. For this reason, the IPCC report suggests that soil carbon sequestration is worth the cost with or without its impact on climate mitigation. And concerning climate change as well, healthy soils, rich in plant detritus and soil biota, are much more effective as a carbon sink when compared to arid or degraded soils.

Options to improve the health of our soils

In the context of countries and regions with large landmasses, such as the United States, China, the European Union (which make up for about 40% of greenhouse gas emissions), mapping and monitoring of soil carbon with the adoption of best practices on sustainable soil management can contribute to their national pledges and climate commitments. 

Estimation of SOC would need to consider the variability of climate, soil, and vegetation, along with analysis of land uses, deforestation, and cropping systems. This would help to determine the SOC sequestration potential and the selection of appropriate strategies to enhance SOC. 

In addition to the SOC mapping, soil carbon sequestration pathways include augmentation of soil carbon sequestration through planting more native species of trees, adoption of agroforestry, and sustainable soil management practices in agriculture such as reduced tillage, application of biochar, intercropping, and rotation of crops which can increase the soil organic matter in the soils. 

We elaborated in an earlier post on the importance of trees and agroforestry for food production and the environment. Planting native species of trees can enrich the soil and help in storing more carbon. More carbon storage in the soil also supports increased retention of water thus mitigating the risk of aridity, droughts, and salinization. 

Growing appropriate tree species on farmlands and adopting agroforestry practices can thus reduce climate vulnerabilities described earlier, enhance carbon storage and improve agricultural productivity.  

At Greenstand, we have been on a mission to restore lands in areas of high climate vulnerability. Our Treetracker platform makes it easy for farmers and our environmentally conscious stakeholders to plant and track the growth of trees. Engaging the local community in the restoration efforts has provided a sustainable source of income for some surviving on less than one US dollar per day. This has also created awareness of the importance of conserving the lands and natural resources for their well-being. 

Since we began operations in 2015, Greenstand has verified over 1.7 million tree photo captures across about 50 countries. Increased local incomes through plantation efforts, thus contributing to climate-proofing of the lands and communities have been and will continue to remain our biggest rewards. You can read more about our efforts here.

Conclusion

Healthy soils are one of the major pools of carbon. Their role is indispensable in climate change mitigation and urgent in the case of vulnerable nations already reeling under increased soil stress (from factors such as droughts, saline water ingress, and degradation linked to climate change). 

Sustainable land and soil management and appropriate strategies to enhance SOC can enhance nations’ efforts towards Nationally Determined Contributions (NDCs) by generating additional carbon sinks via SOC while also fortifying their food and ecological security.

You too can contribute towards healthy soils by supporting initiatives such as planting native tree species, raising your voice against pollution and unsustainable practices, or simply by educating others about the importance of healthy soils. 

Happy World Soil day!


Bhaskar Paul, Communications Contributor

bhaskar.paul@greenstand.org


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