Tuanli

Tuanli (团粒) is a Chinese term referring to soil aggregates, specifically the desirable, stable, and porous structures formed from soil particles binding together. These aggregates are crucial for soil health and fertility. A well-structured soil with abundant tuanli exhibits good water infiltration and retention, aeration, drainage, and resistance to erosion.

Tuanli formation is influenced by several factors, including:

• Organic matter: Decomposing organic material acts as a binding agent, cementing soil particles together.
• Microbial activity: Soil microorganisms, such as bacteria and fungi, produce polysaccharides and other substances that promote aggregation.
• Plant roots: Root exudates and the physical pressure of root growth help bind soil particles.
• Clay minerals: Clay particles, particularly certain types, can contribute to tuanli formation through their surface charges and interactions with other soil components.
• Tillage practices: Certain tillage methods can disrupt tuanli formation, while others, such as conservation tillage, can promote it.

The size and stability of tuanli are important indicators of soil quality. Larger, more stable aggregates are generally associated with healthier soils and improved agricultural productivity. Conversely, soils with poor tuanli structure are often prone to compaction, waterlogging, and nutrient deficiencies.