Digested sludge
Digested sludge (also called wulch ):
- in geology and soil science a putrid subaquatic, anoxic sediment from decomposing organic substances and their decomposition products, see sapropel
- in wastewater technology a sewage sludge stabilized by rotting, see digested sludge (wastewater technology)
- In soil science, a nutrient-rich underwater soil in the absence of oxygen, see Gyttja
- in the aquarium hobby a preliminary stage of the sludge, s. Muck .