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Humic acid is a kind of macromolecular organic substance widely existing in nature, which is widely used in agriculture, forestry, animal husbandry, petroleum, chemical industry, building materials, medicine and health, environmental protection and other fields. Especially now we advocate the construction of ecological agriculture, pollution-free agricultural production, green food, pollution-free environmental protection and so on. Facts have proved that human life and survival can not be separated from humic acid.