2.1. Yield of Humic Acids
2.2. Identification and Comparison of Humic Acids
- It has been commonly believed that Leonardite coal humic acids are different from soil-extracted humic acids, and this finding shows that this was incorrect.
- Kelp extracts are mainly humic acids (as potassium humate), and these humic acids are very similar to soil humic acids. As a side issue, kelp extracts are known to promote plant growth, which may be due to hormones rather than their humic acid content .
- There is a slight difference between the fluorescence spectra of Leonardite coal/kelp humic acids and soil humic acids. This can be explained by a slightly different composition of the suite of humic acids in these samples. This can be explained by differences in the formation of humic acids via the furfural pathway from xylose and fructose (and perhaps ribose and arabinose) in the original plant or algal matter .
4.1. Chemicals and Materials
4.2. Extracting Humic Acids from Senescent Plant and Algal Matter
Conflicts of Interest
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