What is the Difference Between Humic and Non-Humic Substances?

Humic and non-humic substances are fractions of organic matter in the soil, but they differ in their composition and properties. The key difference between them is:

• Humic substances include humic acid, fulvic acid, and humin, and they are formed from the decomposition and transformation of plant and animal residues. They are complex, heterogeneous organic materials that arise from biogeochemical reactions. Humic substances are major components of natural organic matter in soil and water, as well as in geological organic deposits such as lake sediments, peats, brown coals, and shales.
• Non-humic substances include fats, sugars, and amino acids. These substances are discrete compounds that can be placed in specific categories of known biochemistry. Non-humic substances are part of the soil organic matter, but they are not as complex or recalcitrant as humic substances.

Humic substances are important components of soil that affect its physical and chemical properties, while non-humic substances are discrete compounds that can be identified and categorized more easily. The distinction between humic and non-humic substances is not always clear-cut, as some compounds may have properties that overlap with both categories.

Comparative Table: Humic vs Non-Humic Substances

The main difference between humic and non-humic substances lies in their composition and origin. Humic substances include humic acid, fulvic acid, and humin, while non-humic substances include fats, sugars, and amino acids. Here is a table summarizing the differences between humic and non-humic substances:

In summary, humic substances are complex, high molecular weight compounds extracted from humates, while non-humic substances are simpler, low molecular weight compounds found in soil, sediments, and water. Humic substances have a greater biological function compared to non-humic substances.