Wiktionary
n. 1 Two or three species of calcareous algae in the Corallinaceae family, that grow on the seabed. 2 A fertilizer derived from this algae.
Wikipedia
Maerl (or marl) is a collective name for Coralline red algae with a certain growth habit. Maerl grows at a rate of ∼1mm per year. It accumulates as unattached particles and forms extensive beds in suitable sublittoral sites.
Usage examples of "maerl".
The Maerl flowed out of high places in the Westron Mountains, and ran first northeast, then southeast, until it joined the Gray, became part of the Gray, and went eastward to the Soulsease.
Beyond the Maerl was the region where the Lords concentrated their efforts to heal the ravages of Desecration and war.
For all the limitations of their comprehension, the Lords had learned much about the nurturing of damaged earth from the Second Ward, and on this day the Maerl carried only a slight haze of impurity.
Like the Maerl, the Rill had been greatly improved by the long work of the Lords, and the water which flowed from the Valley of Two Rivers no longer deserved the name Gray.