Maakera koostis
Its name
derives from Latin fulvus, indicating its yellow colour.
Its structure is best characterized as a loose assembly of aromatic organic
polymers with many carboxyl groups (COOH) that release hydrogen
ions, resulting in species that have electric charges at various sites on
the ion. It is especially reactive with metals, forming strong complexes
with Fe3+, Al3+, and Cu2+ in particular and leading to their increased
solubility in natural waters. Fulvic acid is believed to originate as a
product of microbial metabolism, although it is not synthesized as a life-
sustaining carbon or energy source.
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