8.3 Wetland and freshwater aquatic ecosystems

A number of wetland and aquatic settings of the world are not on the scale of entire biomes. In terrestrial systems, we often see intermingled ecosystems in places with complex topography – a very tall mountain in the desert Southwest of the US might go from desert at the bottom, through grassland, woodland, dry forest, wetter forest, to alpine tundra. The large swaths of continuous vegetation that are biomes are also not completely continuous – they are dotted with wetlands, cut through by rivers, and where the soil changes or bedrock comes near the surface, areas of different vegetation types will appear – too small to be biomes in their own right.

Terrestrial wetland and aquatic ecosystems are almost never large enough to be considered biomes. Much of the boreal forest is wetland forest, but we label the biome boreal forest. Rivers, lakes, and ponds do not continuously cover the landscape in the way that the major grasslands, deserts, savannas, and forests do. For that reason, this section is about wet terrestrial ecosystems as well as about the aquatic biomes that occur in oceans, where continuously wet environments are the rule. But even in oceans, important features such as coral reefs are not continuous over large areas, and are best discussed as ecosystems.

Read the linked PowerPoint or its .pdf equivalent for an introduction to wetland and freshwater aquatic ecosystems and biomes, their ecology, ecosystem services, and threats.

Knowledge Check

Take a moment to complete the short quiz below to assess your understanding of this section. Read each question carefully and refer to the section content as needed. This quiz is not graded – it’s simply an opportunity for you to reflect on what you’ve learned and reinforce key concepts.