Types of Water

Tanner Pincince Ezra Richardson Jack Belcher


Fresh is the Best

Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, icebergs, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and other total dissolved solids. The term specifically excludes seawater and brackish water although it does include mineral-rich waters such as chalybeate springs.

Different Fresh Water Ecosystems

Freshwater has abundant life in all sorts of biomes

Plants in Freshwater Ecosystems

Plants and algae are important to freshwater biomes because they provide oxygen through photosynthesis, and food for animals in this biome.


Salt Water

What is it?

It would be easy to say that the difference between salt water and fresh water is all about whether there is salt in the water. While it makes sense, that’s not really accurate. Salinity, or the density of salt, is much higher in salt water, but fresh water is not completely devoid of salt.

The salts that are found in salt water, as well as brackish water (which is a mixture of salt and fresh water), are more diverse than the salt most of us have on our dining room table. The water is composed of various elements, and as those elements break down, they become electrically charged ions. These particles are better electricity conductors. This means that electricity flows through salt water more readily and efficiently than it does through fresh water.

Plants And Animals

The dominant life form of coral reefs is coral, which consists of a plant and an animal living together in a symbiotic relationship. The plant part of the coral consists of algae called zooxanthellae. The animals are polyps. The polyps depend on the zooxanthellae's ability to use sunlight to convert carbon dioxide and water into food. In return, the zooxanthellae use the coral's wastes for growth and live within the coral.

There are 120 species of mammals including whales, dolphins, porpoises, seals and sea lions which have evolved to adapt to their aquatic environment by developing small appendages (ears and flippers), a generally large size, hydrodynamic (mechanical properties of liquid) body shapes and different methods to cope with extreme changes in temperature.

Brackish Water

Brackish water or briny water is water that has more salt than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water, or it may occur in old brackish aquifers. Also, certain human activities can produce brackish water. In particular civil engineering projects such as dikes and the flooding of marshlands produce brackish water pools for certain kinds of farming.

Brackish Ecosystems

Brackish water condition commonly occurs when fresh water meets sea water. In fact, the most extensive brackish water habitats worldwide are estuaries, where a river meets the sea. Another important brackish water habitat is the mangrove swamp. Many, though not all, mangrove swamps fringe estuaries and lagoons where the salinity changes with each tide. Some seas and lakes are brackish. The Baltic Sea is a brackish sea adjoining the North Sea. Originally the confluence of two major river systems prior to the Pleistoscene, since that it has been flooded by the North Sea but still receives so much freshwater from the adjacent lands that the water is brackish. Because the salt water coming in from the sea is denser than freshwater, the water in the Baltic is stratified, with salt water at the bottom and freshwater at the top

Brackish Water Plants/Animals

River estuaries form important staging points during the migration of anadromous and catadromous fish species, such as salmon and eels, giving them time to form social groups and to adjust to the changes in salinity. Salmon are anadromous, meaning they live in the sea but ascend rivers to spawn; eels are catadromous, living in rivers and streams, but returning to the sea to breed. Besides the species that migrate through estuaries, there are many other fish that use them as nursery grounds. Although often plagued with mosquitos and other insects that make them unpleasant for humans, mangrove swamps are very important buffer zones between land and sea, and are a natural defense against hurricane and tsunami damage in particular. Because the salt water coming in from the sea is denser than freshwater, the water in the Baltic is stratified, with salt water at the bottom and freshwater at the top. Limited mixing occurs because of the lack of tides and storms, with the result that the fish fauna at the surface is freshwater in composition while that lower down is more marine. Cod are an example of a species only found in deep water in the Baltic, while pike are confined to the less saline surface waters.