Humic acid degrades heavy metal residues in contaminated soil
With the rapid development of the economy, various industrial production processes emit a large amount of wastewater containing heavy metal ions. These heavy metal ions are mostly non-degradable toxic substances and do not have the natural purification ability. Once they enter the environment, they are difficult to remove. Heavy metal ions in the water environment can enter the aquatic organism directly, and then enter the human body through the food chain, accumulating in the human body. Most of the heavy metal ions are highly toxic substances that are carcinogenic, teratogenic and mutagenic, and are ecologically safe and human survival and health. Produce great harm. Therefore, the removal of heavy metals is particularly important today when environmental protection is highly valued.
The accumulation and enrichment of heavy metals bring great pressure to the soil. Most of the forms in the soil are chelated or complex, and humic acid is rich in a large number of ions.
Humic acid can replace heavy metal ions in the chelated and complexed states with its own ions, making heavy metals difficult to be absorbed by crops, and crops are less susceptible to heavy metal contamination.
For example, watering a “super-accumulated plant” kidney fern with a solution containing fulvic acid (a super-accumulating plant means a plant that is tolerant to heavy metals or other contaminants) can significantly increase the absorption of various heavy metals.
Humic acid (including brown humic acid and black humic acid) has a large molecular weight and has the effect of reducing and adsorbing and fixing heavy metals, which can reduce the effectiveness of heavy metals, such as cadmium, mercury, lead and the like.