About 95 percent of our food comes from soils, which have the natural capacity to provide nutrients to support crop growth. Globally, however, not all soils have the same capacity to supply nutrients.

We are currently facing a contrasting scenario of nutrient imbalances. In some regions, soils are naturally infertile and have little or no agricultural capacity; in other regions, soil degradation has reduced fertility. In both situations, crop growth is reduced due to the lack of nutrients in the soil. On the other hand, there are soils where the excessive addition of nutrients, due to improper management, has led to soil, air and water pollution and serious negative effects on terrestrial and aquatic biodiversity. Both of these sharply contrasting nutrient imbalance scenarios contribute to food insecurity and are neither environmentally and economically sustainable nor socially equitable; moreover, they are leading us down a path that exacerbates global climate change and greenhouse gas emissions. 

“Unfortunately, loss of soil fertility means that many vegetables and fruits are not as rich in vitamins and nutrients as they were 70 years ago. Today, two-thirds of the world’s population is at risk of nutrient deficiency,” FAO Director General, Qu DongYU said.

Nutrient imbalance has been identified as a major threat to global soil health, with devastating environmental, social and economic effects both in the Status of the World’s Soil Resources (FAO 2015) and the Voluntary Guidelines for Sustainable Soil Management (FAO 2017). Although 195 million tonnes of fertilizers were applied in 2020, with the annual application rate increasing every year, hunger still affects 768 million people. Nutrient imbalance directly affects food production, quality and safety. Lack of essential nutrients, including macro- and micronutrients, causes underdevelopment of plants and a decrease in yield and nutritional value of crops.

One of the main dimensions of food security is sufficient food production, which can be sustained by improving soil fertility. 

Soil fertility is the ability of soil to support plant growth by providing the essential nutrients and adequate chemical, physical, and biological conditions as a habitat for plant growth and the maintenance of ecosystem services.

The recent FAO report on the State of Food Security and Nutrition in the World confirmed a significant rise in global food insecurity and malnutrition as a consequence of multiple drivers, including the COVID-19 pandemic, climate crisis and ongoing conflicts that have led to rising fuel, feed and fertilizer costs.

Efforts and investments to increase plant nutrient uptake and balance, and ultimately human and animal nutrition, can be lost if soils are not healthy. When soils are compacted, eroded, depleted of nutrients and soil organic matter, or have chemical toxicity problems due to contamination by pollutants, acids or salts, they are unable to produce food containing the nutrients needed for human health, or even to assimilate the nutrients added by fertilizer application.

Whilst the need to increase food production for a growing population is indisputable, the focus should not only be on producing more food, but also on producing better food. Sustainable Soil Management  is essential to preserve and increase the nutrient content in soils, plants, animals and humans. The use of nutrient-rich staple crop varieties, in combination with soil health, is a technological advance to reduce malnutrition, especially if staple crops are grown with, or in rotation with, other species such as native species or legumes, which encourage diet diversity and improve nutrient cycling and biodiversity.

Nutrient imbalance is also a significant driver of environmental degradation and greenhouse gas emissions. Although adding fertilizers represents indisputable benefits for agricultural production, and their proper use may contribute to increased soil health, misuse and overuse of fertilizers increase global climate change, degradation of soil and water resources, and harm human, animal and soil health.

Nutrient imbalance is also a major driver of environmental degradation and greenhouse gas emissions. Although the addition of fertilizers is an unquestionable benefit to agricultural production, and their proper use can contribute to improving soil health, the misuse and overuse of fertilizers increase global climate change, soil and water degradation, and harm human, animal and soil health. 

“We cannot achieve the 2030 Agenda and the Sustainable Development Goals without this transformation and we only have seven years to do so. Healthy soils are our ally to make this transformation a reality,” FAO Director General, Qu DongYU reported.

A growing concern associated with the use of some mineral fertilizers and recycled nutrient sources is their quality and safety. Harmful microbes and heavy metal content can cause serious and persistent environmental pollution and induce significant human health problems. Maintaining soil fertility should not be responsible for environmental pollution resulting from fertilizer extraction and processing. In addition, the depletion of mineral reserves from mining for fertilizer production highlights the urgency of using soil nutrients efficiently, safely and sustainably.

DOWNLOAD THE PUBLICATION Soils for nutrition: state of the art

RELATED LINKS

• The International Code of Conduct for the Sustainable Use and Management of Fertilizers
• FAO and Soil Fertility
• Soils for nutrition video
• Global soil maps and assessments