What Is Plankton and Why Is It So Important?

Learn about the different types of plankton and why they are as crucial for terrestrial environments as they are for life in our oceans.

Mar 29, 2023By Donna Hobson
what is plankton and why is it so important

We might not be able to see them (because they're microscopic), but plankton are vital for supporting almost every form of life on Earth. They support ocean ecosystems and provide over half the world's oxygen, making them essential for our survival.

Discover the different plankton types and their integral role in keeping our planet full of life. Learn why they are so important and what would happen if all the plankton on Earth suddenly disappeared.

What Is Plankton?

microscopic image of plankton
Plankton swimming in dark waters

Plankton are tiny aquatic organisms that play an essential role in the global ecosystem. They are found in oceans, lakes, rivers, and streams and can range in size from microscopic to visible to the naked eye. Plankton provides food for fish, whales, and other marine life and is responsible for producing around 80% of the world's oxygen. They also help to regulate climate by removing carbon dioxide from the atmosphere. Plankton are an important part of the food chain, and their presence is essential for a balanced aquatic environment.

The name "plankton" derives from Greek meaning "wanderer" or "drifter," the latter being a good description of these tiny creatures who spend much of their lives "drifting" along tidal and ocean currents as they are not strong enough to swim against them.

There are several ways in which scientists classify plankton, such as size and type, but the simplest categories separate them into plants (phytoplankton) and animals (zooplankton).

What's The Difference Between Phytoplankton and Zooplankton?

zooplankton in the ocean
Many plankton swimming together

Phytoplankton is a microscopic organism found in the world's oceans and other aquatic environments. It plays an essential role in the marine food web. It is a primary producer of organic carbon and is a significant source of nutrition for many species of fish, invertebrates, and other organisms. Phytoplankton also helps to regulate the global climate by absorbing carbon dioxide from the atmosphere and releasing oxygen into the environment. As such, it is essential to sustaining life on Earth.

Zooplankton are microscopic organisms that inhabit the world's oceans, lakes, rivers, and streams. They play a vital role in the ocean food web as they are a significant food source for fish and other aquatic animals. Zooplankton range in size from microscopic to several centimeters long. They feed on phytoplankton, bacteria, detritus, and organic matter in the water column. By doing so, they help to keep the ocean clean by consuming waste products that would otherwise accumulate.

Although they may appear similar in size, these two plankton species have distinct biological differences. Phytoplankton are photosynthetic organisms that use sunlight to produce energy, while zooplankton are heterotrophic organisms that feed on other organisms for energy. Both types of plankton play a vital role in the marine food web and contribute to the overall health of aquatic ecosystems.

How Do Humans Benefit from Plankton?

oxygen produing phytoplankton

Plankton are essential for maintaining healthy marine ecosystems and providing a source of food for many species. They also provide crucial nutrients for larger animals such as whales and dolphins. Furthermore, plankton are essential for regulating climate change by absorbing carbon dioxide from the atmosphere and helping to reduce global warming.

We often think of trees as our primary source of oxygen, but this is not the case. Phytoplankton generates just as much oxygen as all the plants on Earth combined via their feeding process. These small entities harness energy from the Sun and convert carbon dioxide into body tissues thanks to the presence of chlorophyll in their cells. When this happens, oxygen is created as a byproduct that keeps many terrestrial species alive - including humans.

In short, plankton are essential for sustaining life on Earth, and we must protect them so that future generations can benefit from their many benefits.

Can We Survive Without Plankton?

ocean gathering of plankton
Dozens of plankton swimming on the surface of the water

Without plankton, entire ecosystems could collapse and cause devastating effects on marine life. The loss of plankton would lead to a decrease in oxygen levels, an increase in carbon dioxide levels, and an increase in ocean acidity.

These changes could have far-reaching consequences for all life on Earth, including humans. Without plankton, many species of fish and other marine animals would be unable to survive due to their lack of food sources. This could lead to a collapse in marine biodiversity that would have long-term implications for fisheries and coastal communities worldwide.

How Can We Protect Plankton?

different types of plankton
Close-up of plankton

Unfortunately, these tiny organisms face an uncertain future due to increasing ocean pollution, habitat destruction, and overharvesting. Research has shown the negative impact of human pollution; large concentrations of microplastics prevent these organisms from growing correctly. Furthermore, they can interfere with carbon storage in our oceans.

To protect plankton, we must take action to reduce the amount of pollution entering our oceans, use less energy to reduce the effects of climate change on plankton habitats and work to prevent further destruction of their habitats. We must also stop overharvesting from our oceans if we want to ensure that plankton populations remain healthy in the future. By taking these steps now, we can help protect plankton for future generations.

Donna Hobson
By Donna Hobson

Donna believes that keeping a pet is the key to a happy life. Over the years, many creatures have passed through her home - Sooty the cat, Millie the rabbit, Stuart (Little) the guinea pig, and Trixie the tortoise, alongside her pet goldfish, Zippy, who lived to the grand old age of 24 years! She currently resides with her black kitten Jinx and an aquarium full of fish and snails to entrance them both. When she is not looking after her pets, Donna enjoys researching and writing the answers to all your pet-related wonders.