World Soil Day 2021 – Soil salinisation
World Soil Day is celebrated every year on 5 December as a means of focusing attention on the importance of healthy soil and in favour of sustainable management of soil resources. Each year has a different theme as the main focus of awareness raising.
An international day to celebrate soil was proposed 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 Territorial Cooperation, the United Nations Food and Agriculture Organization (FAO) supported the official establishment of World Soil Day as a global awareness platform. The FAO Conference unanimously endorsed World Soil Day in June 2013 and called for its formal 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.
The date of 5 December for World Soil Day was chosen because it corresponds to the official birthday of His Majesty King Bhumibol Adulyadej, King of Thailand, who officially ratified the event.
Soil salinization: a threat to our global food supply
World Soil Day 2021 (#WorldSoilDay) and its campaign “Stop Soil Salinization, Boost Soil Productivity” aims to raise awareness about the importance of maintaining healthy ecosystems and human well-being by addressing the growing challenges in soil management, combating soil salinization, increasing soil awareness and encouraging societies to improve soil health.
Salinisation is the excessive accumulation of salts in soil
Have you ever seen white crusts in the soil? Soils can be saline. Salts exist naturally in soils and water and move freely through the soil. Naturally salty soils can support rich ecosystems, but natural processes such as drought and human activities, especially improper irrigation, can increase the number of salts in soils, a process called salinization. Soil salinization breaks down our soils and reduces their ability to help grow our food.
Soil salinization and soil sodification are major soil degradation processes that threaten the ecosystem and are recognized as one of the most important problems globally for agricultural production, food security and sustainability in arid and semi-arid regions.
What exactly are saline and sodic soils? Both are soils affected by salts. Saline soils contain high levels of water-soluble salts, such as potassium, magnesium, calcium, chlorine, sulphate, carbonate, bicarbonate, which can negatively affect or even inhibit plant growth. Sodic soils have a high content of adsorbed sodium in the soil particles which causes a degradation of the soil structure.
Soils affected by salts suffer structural deterioration and become hard and compacted
Salt-affected soils have serious impacts on soil functions, such as reducing agricultural productivity, water quality, soil biodiversity and soil erosion. Salt-affected soils have a reduced ability to act as buffers and filters against pollutants. Salt-affected soils reduce both the ability of crops to take up water and the availability of micronutrients. They also accumulate ions that are toxic to plants and can degrade soil structure.
How do we prevent soil salinization and soil sodification?
Let’s see what the main causes of soil salinization and soil sodification are and how we can prevent it:
Common Causes / Preventive Measures
Irrigation with low quality water / Irrigation with water of sufficient quality and/or irrigation with appropriate methods
Insufficient soil drainage / Improve drainage
Deforestation and removal of deep-rooted vegetation / Reforestation and permanent green cover
Seawater intrusion and water pumping in coastal areas / Control of water pumping and monitoring of soil and groundwater salinity
Poor or excessive use of fertilisers/ Consistent use of fertilisers
What can we do to “stop soil salinisation and enhance soil productivity”?
Raising awareness about the importance and impacts of salt-affected soils and supporting the prevention of unsustainable practices that can lead to this
Encourage and promote the use of sustainable agricultural systems adapted to saline/sodic environments
Promote technological innovation for managing salt-affected soils in a sustainable way
Investing in the collection of better knowledge on the status of salt-affected soils at national, regional and global level
Develop policies and implement field actions to integrate science-based soil management practices
Farmers in action: 8 good practices to “stop soil salinisation and boost soil productivity”
Practice alophyte farming (plants resistant to high salinity) and use salt tolerant crops
Water with good quality water, using correct and effective methods
Control groundwater pumping and monitor its quality
Improve drainage systems
Maintain vegetative ground cover
Promote integrated soil fertility management, including the addition of manure
For saline soils: lift the soil substrate, cover with membrane or mulch
For sodic soils: add chemical amendments such as lime or gypsum
Did you know that?
It takes up to 1000 years to build up 1 cm of soil
Soil salinisation removes up to 1.5 million hectares of arable land annually from production
The annual loss in agricultural productivity caused by salinisation is estimated to be €27.4 million (US$31 million)
It is estimated that there are more than 833 million hectares of land already affected by salinity worldwide (8.7% of the planet)
Estimates show that more than 10% of arable land is affected by salts, which poses a major risk to global food security
Some of the regions most affected are Central Asia, the Middle East, South America, North Africa and the Pacific
Watch the official United Nations Food and Agriculture Organization (FAO) video for World Soil Day 2021 raising awareness of soil salinization:
BIOCHEMIKI Analytical Laboratories can assist you with soil analyses as well as drilling and irrigation water analyses. Contact us for more information.
More information sources.
