The array of different types of wetland communities is certainly very complex, and there is controversy among professional aquatic biologists, plant geographers, and ecologists, for which there has never been agreement on a single way to classify freshwater habitats. No simplistic system can reveal the many variants of freshwater communities, nor can a single classification be used to describe and explain the factors controlling these watery communities. One reason why freshwater habitat are difficult to pigeonhole is because there is a tremendous range of climatic, physical, and chemical features:
In general, we are concerned here with the larger plants (macrophytes) found in shallow water, especially the fringing, extremely shallow and well-illuminated littoral zone of lakes, ponds, and rivers, and habitats with shallow standing water, or grasslands and forests that are flooded. Here we cannot be concerned with how lakes originated (e.g., glacial, floodplain, volcanic, rift, or other mechanisms) or with microscopic planktonic plants. Instead, what vascular plants live in these wetlands under what environmental conditions?
For convenience, we will recognize six categories of wetland habitats. Read further about wetlands from the tropics to cold polar and alpine locations.
Also learn about the adaptations of aquatic plants, i.e., the species that inhabit fresh water.