Ombrotrophic ("cloud-fed") refers to soil or vegetation which receive all of their water and nutrients from precipitation, rather than from streams or springs. Such environments are hydrologically isolated from the surrounding landscape, and since rain's acidic and very low in nutrients, they're home to organisms tolerant of acidic, low-nutrient environments. The vegetation of ombrotrophic peatlands's often bog, dominated by Sphagnum mosses. Ombrotrophic circumstances may occur even in landscape… (More on Ombrotrophic)