The improvement effect of Humic Acid on soil - physical effect

Humic acid substances (HS) are an important guarantee for building soil fertility, stabilizing soil quality and maintaining soil safety. Soil fertility refers to the supply of all elements (water, fertilizer, air, heat, etc.) required for crop growth and development, and is also the fundamental characteristic of soil. HS, which accounts for more than 60% of soil organic matter, especially Humic Acid, is the core substance of soil quality and plays a decisive role in soil fertility.

As a natural macromolecular organic matter, Humic Acid has many effects on soil, making the soil fertile and generating land productivity by changing the physical, chemical, nutritional and biological properties of the soil. This article will describe it from the physical aspect.

1. Increase the content of soil organic matter and organic carbon

    The content of soil organic matter and carbon has an important influence on the physical/chemical and biological properties of soil, and is one of the important indicators for evaluating soil quality. The organic matter and carbon content of high-quality arable land should be maintained at 4%~6% and 2%~3% respectively, so that the soil shows a unique dark brown and brown color, thereby increasing the absorption of solar radiation and raising the soil temperature. Generally, dryland soil with more HS is 2~3℃ higher than poor soil; HS also reduces the thermal conductivity of the soil, buffering the sudden fluctuations in temperature to protect soil organisms from harm.

2. HS is the bridge and binder of soil aggregates

    Soil aggregates, also known as "aggregates", are the basis for forming the multi-level structure and multi-level porosity inside soil particles. They are also the elements that constitute the environment for the survival of microorganisms and affect the decomposition, transformation and stability of soil organic carbon. Among them, the content of water-stable aggregates with a particle size of >0.25mm is significantly positively correlated with the content of soil organic carbon. This soil aggregate structure determines its coordination of water, fertilizer, air and heat, and can provide a good growth and development environment for plants.

3. Reduce soil bulk density, increase porosity and water holding capacity

    The improved soil can maintain a loose, porous and small-particle state, thereby improving soil permeability, permeability and water holding capacity, which is more conducive to root elongation and seed germination.

In summary, adding Humic Acid substances and other organic fertilizers is an important way to improve the soil.