Freshwater Ecology Practice Test

Wetlands that form peat do so because waterlogged, low-oxygen conditions slow decay, allowing organic matter to accumulate. When drainage is very poor and rainfall is the main water source, the resulting acidic, nutrient-poor environment supports a thick moss layer—especially sphagnum—often followed by shrubs and evergreen trees rooted in the peat. This combination of peat formation, moss-dominated surface, and woody vegetation matches a bog.

Other options describe different wetland types. A marsh is dominated by herbaceous plants like grasses and reeds and usually not peat-forming. A swamp features more woody vegetation but isn’t characterized by peat accumulation. A pond is open water without peat buildup.