Fulvic Acid, Humin, Gleysolic Soil order, PS 3 5a

Hello!

I am unsure of the difference between Fulvic Acid and Humin. According to Brady and Weil, Fulvic acid is "usually referring to the mixture of organic substances remaining in a solution upon acidification of a dilute alkali extract from the soil" and Humin is “the fraction of soil organic matter that is not dissolved upon the extraction of the soil with a dilute alkali”. Are these two not the same? If humin is the substance removed, is that not the fulvic acid, as that is what was created?

For the gleysolic soil order, would a soil formation process be the translocation of soil moving within the soil (fluctuating water table)?

For question 5 a) of problem set 3, am I correct in thinking that soil formation factors are referring to Time, Topography, Climate, etc? Thank you!

For the key differences between 3 groups of humic substances (where humin & fulvic acids belong), pls refer to the lecture notes from Jan 24 and also summary file also posted under that same date at the "Lecture Notes" page here in wiki.
Definitions that you cite from the textbook are correct, but they refer to the analytical lab methods of determining fulvic acids and humin, not to how those 2 groups of organic compounds are formed (or destroyed) in real life.

Gleying is a soil forming process brought about water table going up & down within the soil profile, which leads to fluctuations of aerobic & anaerobic conditions and that in turn leads to fluctuations in oxidation & reduction of Fe and Al oxides and hydroxide minerals. Those reactions of oxidation & reduction belong to the general group soil forming processes called transformations. In gleying process there is maybe a limited movement of soil material within the soil probes, but there is the pronounced oxidation & reduction, hence it belongs to transformations, not translocations.