Freshwater
Definition of freshwater: A low salt concentration, usually less than 1%.
Ecosystems:
Rivers and Streams
Rivers and streams are passages of moving water that is flowing downhill from a source towards, eventually, almost always, the ocean. The source can be melting snow, springs or lakes. All rivers and streams carry energy with potential energy turning into movement as the water flows downhill. The energy within these systems makes them attractive to humans, as it is possible to harness this power, which also implies a greater threat to the system. During this journey the rivers and streams change appearance and characteristics such as speed, size and temperature. This means that different animals and plants can be found in different parts of the rivers and streams.
Wetlands includes estuaries, floodplains, marshes, lakes, peatlands an swamps. Wetlands are very important for the worlds wildlife with many animals being dependent on them for their livelihood, for example many of the world’s migrating birds are dependent on wetlands for their resting stops. Wetlands are also vital because many humans depend on them for their freshwater supply. In addition to this wetlands play an important role in natural water purification, flood control and shoreline stability. Sadly, wetlands are also one of the most threatened ecosystems in the world, because of human activities such as land drainage for agriculture, urban development and the discharge of pesticides and pollutants.
