1、HUMIC ACID: THE SCIENCE OF HUMUS AND HOW IT BENEFITS SOIL

Humic acid is a group of molecules that bind to, and help plant roots receive, water and nutrients. High humic acid levels can dramatically increase yields. Humic acid deficiency can prevent farmers and gardeners from growing crops with optimum nutrition.

2、Studies on the colour of humic acids: Part 1 on the concepts of humic

It has been fairly well established that humic acids extracted from soils are different from one another, and that the humic acids extracted from a soil can be fractionated by any suitable procedure into two or more fractions which are never clearly distinct.

3、Humic Acids: What They Are and How They Benefit Soil

Humic acids and fulvic acids are both components of humic substances, formed from the same decomposition processes of organic matter. However, they differ in their molecular characteristics and functional roles.

What Are Humic Substances and How Do They Work?

Fulvic acid is highly soluble in water across the entire pH spectrum. This fraction is lighter in color, appearing yellow to yellow-brown, and contains a higher proportion of oxygen-containing functional groups compared to humic acid.

Humic Acids: Overview and prospective with especial

Calorimetrically, humic acids obtained from the lignite coal is yellow, black and brown colored which is extracted conventionally for the humic acids (via alkali followed by acid...

Chemistry:Humic substance

The colour of humic substances varies from yellow to brown to black. Humic substances represent the major part of organic matter in soil, peat, coal and sediments and are important components of dissolved natural organic matter (NOM) in lakes (especially, dystrophic lakes), rivers and sea water.

Humic Acid vs Fulvic Acid: Key Differences and Best Uses

Fulvic acid is a lower-molecular-weight compound and is completely soluble in water under all pH conditions. It is more yellow or amber in color and has a much smaller molecular size compared to humic acid, making it more bioavailable to plants. Humic acid is more effective when applied to soil.

Humic acid vs. Fulvic acid

The color of fulvic acid is ranged from yellow to light brown. Fulvic acids are more active than humic acids due to its oxygen content that is almost double the amount of humic acid.

Classification of humic acids

According to the formation mode, humic acid can be divided into primary humic acid and regenerated humic acid (including natural weathered coal and artificial oxidation of coal humic acid) .

What Is Humic Acid?

Humic acids are complex molecules that exist naturally in soils, peats, oceans and fresh waters. The one source of humic acids are the sedimentation layers referred to as Leonardite.

Yellow-brown humic acid and humic acid both refer to organic substances that play critical roles in soil. differences arise between them due to their distinct sources, structures, and properties.

Firstly, differences in origin: Humic acid primarily forms from the decomposition of plant and animal residues in soil, influenced by factors like climate and soil type. In contrast, yellow-brown humic acid may derive from specific plants or animals in unique environments, such as those found in yellow-brown soils. Its formation is often shaped by particular geographic conditions and biological activities.

Secondly, structural differences: Humic acid is a complex organic compound composed mainly of carbon, hydrogen, nitrogen, and oxygen, with a relatively intricate molecular structure. Yellow-brown humic acid, may contain higher amounts of organic materials like proteins, fats, and sugars, leading to a more complex molecular composition. Additionally, it might include specialized compounds such as lignin and cellulose, which distinguish its properties and functions from ordinary humic acid.

Thirdly, differences in properties: Humic acid is known for its strong adsorption capacity, retaining water and ions to enhance soil moisture and fertility. Yellow-brown humic acid, meanwhile, often exhibits superior adsorption capabilities, especially for heavy metal ions. It also tends to have greater stability and temperature resistance, maintaining its structure and properties across broader thermal ranges.

Finally, differences in applications: Due to its unique traits, yellow-brown humic acid is commonly used in soil amendments and fertilizer additives. For example, it improves soil physical-chemical properties, boosting water retention, fertility, and crop yield. Ordinary humic acid, is widely applied in agriculture as an organic fertilizer to enhance crop growth and productivity.

while both yellow-brown humic acid and humic acid are organic substances, they differ in origin, structure, properties, and usage. These variations stem from their formation environments, compositional complexity, and functional characteristics. Understanding these distinctions helps optimize their roles in agricultural and environmental practices.