5 December: World Soil Day

World Soil Day: United Nations Declaration and FAO’s Leadership

World Soil Day (WSD) is a global observance dedicated to highlighting the vital role of healthy soils. The initiative was first proposed by the International Union of Soil Sciences (IUSS) in 2002. With strong advocacy from the Kingdom of Thailand and the support of the Global Soil Partnership, the Food and Agriculture Organization (FAO) of the United Nations played a pivotal role in establishing World Soil Day as a platform for international awareness and action.

In June 2013, the FAO Conference unanimously recommended the adoption of World Soil Day. The 68th United Nations General Assembly subsequently designated 5 December 2014 as the inaugural World Soil Day, launching an annual event to recognize soil’s essential contribution to life on Earth.

The Importance of Plants and Soil Biodiversity

Soil is far more than the ground beneath our feet—it is a dynamic ecosystem rich with life. Plants depend on soil, which hosts a diverse community of organisms that nourish and protect them. This biodiversity is crucial for maintaining soil health and fertility, driving the biogeochemical cycles that underpin all terrestrial life.

Healthy soils support robust plant growth, which in turn sustains animals and people. The intricate web of soil organisms facilitates nutrient cycling, disease resistance, and carbon storage—processes vital for ecosystem balance and agricultural productivity.

FAO’s Commitment to Soil Conservation

The FAO leads global efforts to address the urgent challenges of soil management. The 2023 campaign, “Keep soil alive, protect soil biodiversity,” highlights the need to preserve healthy ecosystems for human well-being. This initiative calls on individuals and communities worldwide to take action to restore soil health and halt the alarming decline in soil biodiversity.

Without immediate intervention, declining soil fertility threatens global food security and nutrition. Protecting soil biodiversity is fundamental to ensuring the future of agriculture and environmental sustainability.

Types of Soil

Soils are commonly classified by particle size into three main types: silt, clay, and sand. Each type has distinct properties that affect water retention, nutrient availability, and aeration.

Loam is a balanced blend of sand, silt, and clay—often with a significant clay component—making it ideal for plant growth. Humus refers to the organic matter found primarily in the top “O” layer of soil. While humus enriches soil fertility, it is not a soil type itself.

Although pollution is often associated with air and water, soil pollution is a critical issue that directly impacts the safety and quality of fruits and vegetables. Contaminated soils can affect human health through the food chain, highlighting the urgent need to protect and restore soil resources.

Soil Degradation and the Impact of Pollution

Modern soil degradation is driven by several factors, including:

• Erosion
• Loss of organic carbon
• Increased salinity
• Soil compaction
• Acidification