A man checks a soil affected by salinity
Soil salinization and sodification are among the most important problems at a global level for agricultural production, food security and sustainability in arid and semi-arid regions.
Photo:International Rice Research Institute (IRRI).

Soil salinization: a threat to our global pantry

Have you ever seen white crusts on soil? Yes, it is what you think. Soils can be salty. Salts are present naturally in soils and water, and they move freely through the soil. Naturally saline soils may support rich ecosystems, but natural processes such as droughts and human activities, especially improper irrigation, can increase how many salts are in soils, a process that is called salinization. Soil salinization breaks down our soils and reduces their ability to help our food grow.

Soil salinization and sodification are major soil degradation processes threatening ecosystem and are recognized as being among the most important problems at a global level for agricultural production, food security and sustainability in arid and semi-arid regions.

Salt-affected soils have serious impacts on soil functions, such as in the decrease in agricultural productivity, water quality, soil biodiversity, and soil erosion. Salt-affected soils have a decreased ability to act as a buffer and filter against pollutants. Salt-affected soils reduce both the ability of crops to take up water and the availability of micronutrients. They also concentrate ions that are toxic to plants and may degrade the soil structure.

World Soil Day 2021 (#WorldSoilDay) and its campaign "Halt soil salinization, boost soil productivity" aims to raise awareness of the importance of maintaining healthy ecosystems and human well-being by addressing the growing challenges in soil management, fighting soil salinization, increasing soil awareness and encouraging societies to improve soil health.

To commemorate the Observance, FAO will hold a virtual ceremony on 3 December (12:30 - 13:30 CET) with the participation of the fFAO Director-General and thousands of soil enthusiasts. Artistic performances and keynotes will animate the ceremony and the winners of the Glinka World Soil Prize and King Bhumibol WSD award will also be announced. Interpretation will be available in the six UN official languages. Register here!

Observance Day poster 2021

Get the message across!

FAO’s website is full of initiatives and materials to raise awareness and disseminate these Observance’s goals on different platforms. Get to know multitude of worldwide events related to the growing threat of the salinization of soils.


World Soil Day (WSD) is held annually on 5 December as a means to focus attention on the importance of healthy soil and to advocate for the sustainable management of soil resources.

An international day to celebrate soil was recommended by the International Union of Soil Sciences (IUSS) in 2002. Under the leadership of the Kingdom of Thailand and within the framework of the Global Soil Partnership, FAO has supported the formal establishment of WSD as a global awareness raising platform. The FAO Conference unanimously endorsed World Soil Day in June 2013 and requested its official adoption at the 68th UN General Assembly. In December 2013, the UN General Assembly responded by designating 5 December 2014 as the first official World Soil Day.

Did you know?

  • Soil salinization takes up to 1.5 million ha of farmland per year from production
  • The annual loss in agricultural productivity caused by salinization is estimated to be of US$ 31 million
  • It is estimated that there are more than 833 million hectares of salt-affected soils around the globe (8.7% of the planet).

Source: FAO 2021


Get to know all events around the world and register yours!





Plant coming out of a dry crack of land

FAO has launched the Global Map of Salt-Affected Soils. Most of them can be found in naturally arid or semi-arid environments in Africa, Asia and Latin America. The map allows experts to identify where sustainable soil management practices should be adopted to prevent salinization.

In order to educate children about the need for healthy soils, FAO published "Salty experiments with soil for children" in which they will start a journey to discover how food begins beneath our feet; the second initiative is "Living in the soil", a story in comic format to learn soil’s secrets and possible solutions to keep it alive.

illustration of people with clock, calendar, to-do list and decorations

International days and weeks are occasions to educate the public on issues of concern, to mobilize political will and resources to address global problems, and to celebrate and reinforce achievements of humanity. The existence of international days predates the establishment of the United Nations, but the UN has embraced them as a powerful advocacy tool. We also mark other UN observances.