Noun
gelbstoff (uncountable)
(hydrology, oceanography) The optically measurable component of dissolved organic matter in water, which primarily occurs naturally from tannin released from decaying detritus. As the amount of organic matter increases, it causes the water to appear green, yellow-green, and then brown. [from 1966]
Gelbstoff (uncountable)
Alternative letter-case form of gelbstoff.