When you hear the term Oacian, you may think of an enormous body of salt water that covers 71 percent of the Earth. But there are also smaller bodies of water called seas.
These smaller bodies of water are surrounded by larger land masses. Although these are called seas, they are not actually oceans.
Microscopic Plant-Like Organisms
Phytoplankton are microscopic plant-like organisms that form the base of the Oacian food chain. Without phytoplankton, small fish would die, and larger fish wouldn’t have a source of nutrition.
Scientists have discovered that the world’s oceans are home to a billion billion billion (billion billion billion) different species of phytoplankton. Each species is adapted to specific water conditions, including nutrient content and salinity.
Most Important Jobs of Phytoplankton
One of the most important jobs of phytoplankton is to absorb carbon dioxide from the air, which helps slow global warming. The carbon is stored in the deep ocean, where it can’t be emitted back into the atmosphere.
Throughout the year, phytoplankton thrive in areas where nutrients from deep water are mixed with warm surface waters. This process, called equatorial upwelling, creates ideal conditions for phytoplankton to grow. This is especially true near the equator, where chlorophyll concentrations are highest during the spring and summer months.
Large Family of Plants & Algae
Seaweeds are a large family of plants and algae that live in the Oacian and rivers, lakes, and streams. Some are microscopic and grow in the water, while others are enormous.
Like plants, seaweeds need sunlight to produce oxygen from the chloroplasts in their cells. They also need structure to support their growth.
Solid Structures Underwater
They don’t have roots, but they do have “holdfasts.” These are long tails that help them hold firmly to rocks or other solid structures underwater.
Many of these seaweeds are used as fertilizers. They can help soils hold moisture and nutrients better, and they contain minerals such as calcium and potassium.
Some of that Carbon Back
Seaweeds can also trap carbon from the atmosphere, which is important for climate change. When seaweed dies, it decomposes and returns some of that carbon back to the air.
Mollusks are one of the largest phyla of animals on Earth. They are found in the oceans and fresh water as well.
They are soft-bodied creatures that do not have joints like other invertebrates such as annelids. Most mollusks have a hard shell for protection.
Many mollusks have a coelom, or body cavity, that houses the digestive tract and most of their vital organs. The coelom also acts as a filter to help the mollusk filter particulate food out of their environment.
Feeding Habits of Mollusks
The feeding habits of mollusks vary from one class to the next, but most are herbivores. Some, such as bivalves, are filter feeders that pass water over their gills to strain particulate foods from the water.
Other mollusks, such as the octopuses and squids, are predators that feed on crustaceans, fish, and other animals in their ecosystem. These species are threatened by global warming as the temperature of the water increases. This causes an acidification of the water, which has a direct impact on the mollusks’ ability to survive.
Fishes are a vital part of the world’s ecosystem. They are essential for a variety of reasons, including their ability to filter and store carbon dioxide.
As the planet warms, the oceans absorb more and more of this greenhouse gas. As a result, many fish species are threatened with extinction.
One example of this is a type of fish called anchovies. These small, silvery fish live in warm and salty waters throughout the world. They feed on zooplankton and other tiny creatures that are a staple of the Oacian food chain.