棕腐质的

Ulmic \Ul"mic\, a. [L. ulmus an elm: cf. F. ulmique.] (Chem.)
Pertaining to ulmin; designating an acid obtained from ulmin.

Humin \Hu"min\, n. [L. humus the earth, ground.] (Chem.)
A bitter, brownish yellow, amorphous substance, extracted
from vegetable mold, and also produced by the action of acids
on certain sugars and carbohydrates; -- called also {humic
acid}, {ulmin}, {gein}, {ulmic} or {geic acid}, etc.