What are Humic Substances and How Do They Help with Climate Control by Sequestering Carbon?
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- Definition of Humic Substances
- Humic Substances Properties
- Humic Structures and Reactions
- How do Humics Remain stable?
- HAs for Soil Enhancement, Water Treatment, Recycling and Carbon Sequestration
- How HA Production from Bio-Waste and Coals helps in Repairing Impaired Lands and Arid Areas while Sequestering Carbon
- How to Calculate Carbon Sequestration Potential from Applications of Humic Substances
- Bibliography
- References
- Additional Reading
Humic Acid Structures and Reactions
Although the detailed molecular structures of HAs are unknown at present, HAs behaved as if they have two main structural features. One feature is chemical functional groups, which help HAs to direct physical and chemical reactions. Chemical functional groups present are: carboxylic, phenolic, aliphatic and enolic-OH and carbonyl (C=O). Example of a physical reaction is the binding of a plant nutrient metal such as magnesium (thus concentrating the metal for absorption through the plant roots). Another is binding of a toxic metal such as cadmium (tying up the metal and keeping it out of the water supply). Another physical reaction is retention of water, which is essential for plant growth.
HA’s also direct chemical reactions because they can accept and donate electrons. For example, HA’s can convert carcinogenic chromate in the water from plating and tanning factories to non-toxic chromic ions. A biochemical example is that HAs act as mediators in the reactions of microbes with iron-containing minerals. The HAs help to transfer electrons produced by the microbes to the minerals as the microbes eat and grow. The microbes themselves cannot interact directly with the minerals, but HAs can.