How does soil degradation reduce the world’s capacity to produce food?

Soil degradation reduces the world’s capacity to produce food by destroying the physical, chemical, and biological properties that make land productive. When topsoil erodes, compacts, or loses organic matter, crops yield less, require more inputs to maintain output, and in severe cases can no longer be farmed at all. The sections below examine the causes, consequences, and scale of this challenge, and what can realistically be done about it.

What are the main causes of soil degradation worldwide?

The main causes of soil degradation worldwide are erosion by water and wind, compaction from heavy machinery, salinisation from poor irrigation, nutrient depletion from intensive cropping, acidification from excess fertiliser use, and contamination from industrial chemicals. These processes are driven by a combination of unsustainable land management practices and the compounding effects of climate change.

Erosion is among the most widespread forms of degradation. When rain or wind strips away the nutrient-rich upper layer of soil, it removes the very material that supports plant growth. Compaction is equally damaging in its own way: when soil particles are pressed together by heavy equipment or intensive livestock grazing, the pore spaces that allow water and air to move through the soil collapse, leaving roots starved of both moisture and oxygen.

Salinisation, the build-up of salts caused by improper irrigation, affects a significant share of the world’s irrigated farmland, particularly in arid regions where water evaporates quickly and leaves mineral deposits behind. Meanwhile, monoculture farming and the over-application of nitrogen fertilisers accelerate nutrient depletion and acidification, gradually stripping soils of their natural fertility. According to the Soil Atlas 2024, around 18.1 million square kilometres of land are already degraded globally, with unsustainable agricultural practices and deforestation accounting for the majority of that damage.

Underlying many of these pressures is rural poverty. Smallholder farmers in developing regions often lack the resources to invest in soil conservation, meaning short-term survival takes precedence over long-term land health. Climate change intensifies all of these dynamics: extreme rainfall events accelerate erosion, while prolonged droughts leave bare, compacted surfaces vulnerable to wind damage.

How does soil degradation directly reduce crop yields?

Soil degradation reduces crop yields by depleting the organic matter, nutrients, and water-holding capacity that plants depend on. As topsoil is lost or its structure breaks down, crops produce less per hectare, become more vulnerable to disease and drought, and respond less effectively even when farmers apply additional fertiliser.

Soil organic matter sits at the centre of this relationship. It acts as a reservoir for nutrients, a sponge for water, and a habitat for the microbial communities that drive nutrient cycling. When organic matter declines, all three functions weaken simultaneously. Research published in 2025 found that for each unit of soil organic carbon lost, maize and soybean yields fell measurably, illustrating how closely productivity tracks soil health at a fundamental level.

Compaction compounds the problem. In Europe, compaction alone can reduce crop yields by between 2.5 and 15 per cent, depending on soil type and crop. Compacted soils hold less water, so crops become more susceptible to drought stress even when rainfall is adequate. The damage is self-reinforcing: stressed crops produce less root biomass, which means less organic matter returns to the soil, accelerating the decline.

Erosion creates a similar feedback loop. Once the fertile topsoil layer is gone, applying more fertiliser does not fully compensate. Studies from the US Corn Belt have shown that fertiliser applied to eroded soils does not restore yields to the levels recorded on intact, non-eroded land. In Sub-Saharan Africa, where erosion rates can be particularly severe, yield losses in the most affected areas can reach 30 to 50 per cent. Across the EU, soil erosion already costs millions of tonnes of wheat and maize production every year.

How much agricultural land has already been lost to degradation?

The scale of agricultural land lost to degradation is substantial. Approximately 1.2 billion hectares of land have been degraded since the Second World War, and at least 100 million hectares of healthy land continue to be lost every year. The United Nations estimates that around 30 per cent of the world’s soils are now moderately to highly degraded.

These figures carry serious implications for food supply. Soil forms slowly: the FAO estimates that regenerating just 2 to 3 centimetres of topsoil can take up to 1,000 years, which means that on any timescale relevant to human food systems, lost topsoil is effectively a non-renewable resource. Land that degrades beyond a certain threshold does not simply recover when pressure is removed.

The geographical concentration of losses matters as much as the total. Two-thirds of degraded land since the mid-twentieth century is located in Asia and Africa, the same regions where food insecurity is most acute. In Sub-Saharan Africa, roughly 65 per cent of arable land is now classified as moderately to severely degraded. At least 60 per cent of soils across the EU are affected by at least one form of degradation, according to the EU Soil Observatory.

Desertification and drought alone remove approximately 12 million hectares of soil from productive use each year. Across the world, an area equivalent to four football fields becomes degraded every second. These are not projections; they describe what is already happening.

Which crops and regions are most vulnerable to soil degradation?

The regions most vulnerable to soil degradation are Sub-Saharan Africa, South Asia, and southern Europe, where a combination of intensive land use, climate stress, and limited soil conservation resources creates the highest risk. Among crops, those grown in continuous monocultures on exposed soils, including cereals and certain legumes, face the greatest yield losses when soil health declines.

Sub-Saharan Africa stands out as the most severely affected region. Approximately 65 per cent of its arable land is moderately to severely degraded, and staple crops such as maize, which is both nutrient-demanding and sensitive to poor soil fertility, are particularly exposed. Oil palms, widely grown across West and Central Africa, are also associated with nutrient depletion under intensive cultivation. The convergence of high degradation and high food insecurity in this region makes the challenge especially urgent.

In South Asia, the combination of steep-land cultivation, flood irrigation, excessive ploughing, and uncontrolled grazing drives degradation across large agricultural areas. Irrigated lands in the region suffer from salinisation, which progressively reduces the area available for productive farming. In Europe, the highest degradation risk is concentrated in southern and eastern areas, where intensively managed and sparsely vegetated landscapes are most exposed to erosion. Rainfed croplands across Eastern Europe have shown increasing degradation risk over the past two decades.

Highly fertile black soils, which represent a disproportionately important share of global food production given their natural productivity, are under particular pressure in China, North America, and Ukraine. These soils are difficult to replace and slow to form, making their degradation a long-term structural risk to global food supply rather than a localised or temporary problem.

Can degraded soil be restored to productive farmland?

Degraded soil can be partially or substantially restored to productive farmland, but recovery is slow, context-dependent, and rarely complete in the short term. Restoration approaches including cover cropping, organic amendments, reduced tillage, and the use of biochar or microbial inoculants have demonstrated genuine improvements in soil function, though the pace of recovery depends heavily on the type and severity of degradation.

Regenerative approaches that prioritise returning organic matter to the soil tend to produce the most consistent results. Cover cropping protects bare soil from erosion and adds biomass that feeds soil biology. Diversified crop rotations reduce the nutrient depletion and pest pressure associated with monocultures. Reducing tillage preserves soil structure and limits the disruption of microbial communities. These practices do not deliver instant results, and some show short-term yield reductions during the transition period before soil function improves.

Biochar, a carbon-rich material produced by heating organic matter, has shown promising results in degraded soils specifically. It improves the soil’s capacity to retain nutrients and water, and can reduce compaction. Compost and biochar applied together have been shown to improve soil fertility and reduce the mobility of contaminants in heavily degraded or polluted soils. Microbial inoculants, including beneficial fungi and bacteria, can help restore nutrient cycling in soils where biological activity has been severely diminished.

Where soil degradation is severe or where land has been effectively removed from production, greenhouse cultivation using professionally engineered growing media offers an alternative pathway for food production that does not depend on soil quality at all. Kekkilä-BVB, which develops high-quality growing media for professional greenhouse growers, notes that controlled growing environments using substrate-based cultivation can yield significantly more food per unit of area than field production, while using substantially less water and fewer inputs. This does not restore degraded land, but it does allow food production to continue and expand in regions where soil health has declined. The company projects that demand for growing media will need to grow substantially over the coming decades as productive arable land becomes scarcer.

Global restoration targets are ambitious. Meeting international pledges would require restoring hundreds of millions of hectares of degraded agricultural land by 2030. Whether that is achievable at scale depends on sustained investment, policy support, and the adoption of soil-conscious practices by farmers across very different economic and ecological contexts.

What does soil degradation mean for long-term global food security?

Soil degradation poses a serious long-term threat to global food security by steadily reducing the productive capacity of the land that most of the world’s food depends on. As soils degrade, farmers must spend more to achieve the same or lower yields, and the most vulnerable populations, particularly smallholder farmers in developing regions, are the least able to absorb those additional costs.

The arithmetic of the challenge is stark. The world’s population is projected to reach close to 10 billion by 2050, requiring substantially more food than is produced today. At the same time, degradation is shrinking the effective area of productive farmland. The UNDRR projects that if current trends continue, more than 90 per cent of the Earth’s land area could be substantially degraded by 2050, with average global crop yields falling by around 10 per cent and by up to 50 per cent in the worst-affected regions.

Degraded soils are also less resilient to climate shocks. Healthy soil with good organic matter content absorbs and retains rainfall, buffering crops against drought. Degraded soils lose this capacity, meaning that the same weather event causes greater crop losses on compromised land than it would on healthy land. This dynamic links soil degradation directly to climate vulnerability, creating compounding risks for food systems in already fragile regions.

The policy response is beginning to catch up. The EU’s Soil Monitoring and Resilience Directive, formally adopted in September 2025, establishes the first EU-wide framework for assessing and monitoring soil health across all land types, with a goal of achieving healthy soils across Europe by 2050. This represents a significant regulatory shift, recognising that soil is a shared resource whose condition has consequences well beyond individual farms.

Ultimately, soil health is foundational to food security in a way that cannot be substituted away entirely. Around 92 per cent of the food consumed globally originates from the soil. Protecting and restoring that resource, while developing complementary approaches such as professional greenhouse cultivation using substrate-based growing media where soil-based production is no longer viable, is central to the challenge of feeding a growing world with finite and increasingly pressured land.