Soil granular structure is a soil structure formed by several individual soil particles bonded together to form aggregates. Because small pores exist between individual particles and large pores exist between aggregates, its total porosity is larger compared to single-particle structures. Small pores retain moisture, while large pores allow for aeration. Granular soil structure ensures good root growth for plants and is suitable for crop cultivation.

Core Functions of Granular Structure

1. Coordinating Water and Air Conflicts, Acting as a "Dispatch Center"
   Granular structure has an excellent ability to coordinate water and air, acting as the key to resolving the water-air conflict in soil. Aeration pores exist between aggregates, allowing for rapid infiltration and reducing surface runoff and soil erosion; soil air circulation meets the respiratory needs of plant roots and microorganisms; the interior of aggregates is filled with capillary pores, which can absorb and retain moisture, preventing excessive evaporation during droughts; the stable pore structure can mitigate drastic temperature changes, creating an excellent environment for plant growth with coordinated water, fertilizer, air, and heat.

2. Nutrient Retention and Supply: Becoming a "Nutrient Bank"
   Soil aggregates act as "storage depots" and "conversion stations" for soil nutrients. Organic matter and applied fertilizers are mostly adsorbed on the surface and inside the aggregates. This physical protection reduces the loss of soluble nutrients with water. The anaerobic environment inside the aggregates promotes the accumulation and slow decomposition of organic matter, while the aerobic environment outside facilitates microorganisms mineralizing organic nutrients into inorganic forms that plants can absorb. This dynamic balance ensures a continuous and stable supply of nutrients.

3. Maintaining Biodiversity and Building a "Living Paradise"
   Because soil aggregates contain both large and small pores in appropriate proportions, the diverse water and air environment and the diverse supply of matter and energy provide a favorable living space for animals and microorganisms of different sizes and with aerobic and anaerobic lifestyles. The life activities of these organisms further promote the formation of new aggregates, creating a virtuous cycle.

4. Improving Tillability and Enhancing Resilience
   Soil with a good aggregate structure is loose and soft, with low tillage resistance, a long suitable tillage period, and low energy consumption. Its robust pore system allows the soil to expand and contract evenly during alternating wet and dry periods, preventing compaction or cracking. Furthermore, this structure buffers sudden temperature changes and, like a sponge, enhances the soil's drought and flood resistance.

Soil aggregate structure is the lifeline of soil health. Protecting soil aggregate structure requires the rational application of organic fertilizers, reducing the overuse of chemical fertilizers, avoiding excessive deep plowing, and maintaining its stability through ecological farming methods. This is fundamental to improving soil fertility and ensuring food production.