Aquatic Biome

By: Shakalya Robertson

Aquatic Biome

  • The aquatic biome is definitely the largest biome out there. Water covers nearly 75 percent of the earth's surface, in the form of oceans, lakes, rivers, etc. Just like all other biomes, the aquatic biome can be divided into two categories: freshwater regions and saltwater regions.

Freshwater Regions

  • Freshwater is defined as having a low salt concentration. Usually less than 1%. Plants and animals in freshwater regions are adjusted to the low salt content and would not be able to survive in areas of high salt concentration. There are different types of freshwater regions: ponds and lakes, streams and rivers, and wetlands. The following sections describe the characteristics of these three freshwater zones.

Where Can We Find It?

  • Pretty much all around the world. Aquatic regions are everywhere.
  • Florida, Amazon River, lakes in Russia.


  • The climate of the marine biome is mostly varied. Since it is the largest biome in the world, the climate varies from -40 degrees fahrenheit to over 100 degrees. The average temperature is 39 degrees fahrenheit, but it is warmer near the equator where the direct rays of sun can pierce the water and warm it. The coldest is in the north and south poles, where the water is close to freezing if not frozen (Glaciers). Also, the deeper the ocean is, the colder the water will be because the sunlight isn't directly piercing it.

Plants & Animals

  • The main kinds of animals in the sea are whales, dolphins, sharks, and seals which are some of the most popular kinds of sea mammals. Other kinds of animals and fish that live in the sea are the walrus, star fish, eel, crabs, jellyfish, and fresh and saltwater fish. There are plenty of animals that live just on land around the water. They include the racoon, earthworms, and possums. The area is also very dominant by the presence of mosquitoes.
  • Kelp is a plant that grows in the ocean, Green Algae, and Seagrass. Diatoms and Dinoflagellates are the most commonly found phytoplankton in the aquatic biome.

Soil Found in Freshwater Biomes


  • Water is able to drain relatively easily through silt, but since its particles are packed decently, it retains moisture. Many plants like to live in a freshwater biome with this soil, due to its available air flow and nutrients that it supplies.


  • Because sand is not able to hold much moisture or nutrients, many complex plants do not live in it, although it is the most found soil out of all freshwater biomes. As long as there is at least some silt and clay mixed in, it makes for a good soil for plants.


  • Because of its great density, airflow does not circulate well through it, although it is rich in nutrients for those plants that don't require a lot of air to survive.

Abiotic Factors

  • These include the chemical and physical environmental factors such as sunlight, temperature, water or moisture and soil.

Biotic Factors

Factors include interactions, conditions and energy created or changed by living things. Aquatic ecosystems are affected by five biotic factors: competition, predation, symbiosis, decomposition and disease.