Improper water management, including insufficient supply and poor-quality drainage systems, are contributing to excessive soil salinisation – a problem that threatens global food security, according to the UN’s Food and Agriculture Organization (FAO).
Soil salinisation refers to excessive levels of salt in the soil, which can inhibit plant growth and even be toxic to life. It can occur naturally, for example in deserts due to lack of water and intense evaporation, or because of human activity.
The UN agency highlighted the issue while observing World Soil Day on December 5. The day was organised around the theme of Halt soil salinisation, boosting soil productivity.
“Soil is the foundation of agriculture and the world’s farmers depend on soil to produce about 95 per cent of the food we eat. Yet, our soils are at risk,” said Qu Dongyu, FAO Director-General.
FAO said unsustainable agricultural practices and overexploitation of natural resources, as well as a growing global population, are putting increased pressure on soils and causing alarming rates of soil degradation worldwide. More than 833 million hectares of soils are already salt-affected, representing around 9 per cent of the world’s land surface, or roughly four times the size of India. Salt-affected soils occur in all continents, and under almost all climatic conditions, but more than two-thirds are in arid and semi-arid zones. Some of the regions most affected are Central Asia, the Middle East, South America, North Africa and the Pacific.
A case in point is Uzbekistan, the world’s largest landlocked country that is surrounded by other landlocked nations. The Central Asian country has more than half of its soils affected by salt, making it extremely difficult to farm productively. Over the years, many people from difficult areas have left because of the heat, dry weather and water shortages.
However, in other regions of the world, soil salination is attributed to unsustainable human activities, such as overuse of fertilisers, inappropriate irrigation methods, poor quality water and deforestation.
In response to the challenge, in Uzbekistan, FAO has a Global Soil Partnership (GSP), where the UN agency collaborates with scientists to develop climate-smart soil management practices so that crops in salt-affected areas can thrive.
FAO has also stressed the importance of generating reliable soil data, though it warns that many countries face challenges in this area. The agency has published the Global Soil Laboratory Assessment Report, which reveals that out of 142 countries surveyed, 55 per cent lack the adequate capability for soil analysis. Most are in Africa and Asia.