What are algae?

Algae are a type of organism that is often referred to as ‘simple’ plants, although they aren’t really planted at all. Algae can be found in many different types of environments and have a variety of different reproductive methods. They are photosynthetic organisms. Algae are aquatic plants composed of single or multiple cells. They can be single-celled like diatoms or large collections of cells like kelp forests.

Algae’s carbon-capturing potential

In addition to reducing the number of greenhouse gases emitted by fossil fuels, algae can also reduce the amount of carbon dioxide in the atmosphere. Every day, algae absorb CO₂ from the air and turn it into oxygen, which is then released back into the atmosphere. They emit oxygen for CO₂ they consume for photosynthesis.

While other plants absorb CO2 as well, algae have more power to reduce atmospheric carbon than most other plants because it does so at an unusually fast rate. This leads to a variety of benefits for climate change mitigation through its use as a biofuel or biodiesel source.

Algae sequester phosphorus and nitrogen

Agricultural fertilizer is the single largest source of phosphorus and nitrogen runoff, which can contribute to harmful algal blooms in water systems. Because algae naturally sequester phosphorus and nitrogen, it can be used as an effective way to help keep these nutrients at acceptable levels, thereby reducing the risk of harmful algal blooms. In fact, a study conducted shows that algae accumulate much more phosphorus than plants do.

But how are algae able to reduce excess amounts of phosphorus and nitrogen in our environment?

First of all, you should know that phosphorus and nitrogen are essential for plant growth. But there is a problem with too much of a good thing! When large quantities of these elements enter bodies of water through runoff or direct discharges from wastewater treatment facilities (and let’s not forget that fertilizer from agricultural areas also makes its way into natural waterways), they can stimulate rapid plant growth. This produces cyanobacteria, more commonly known as blue-green algae. If this problem is persistent enough to cause a whole body of water to experience such growth, we call it a “harmful algal bloom” (HAB).

Algae absorb more carbon than most plants

You might not think of algae when you think of plants, but the stuff is actually a plant! While they’re tiny and often overlooked, their ability to absorb carbon dioxide is impressive. Algae absorb CO2 through photosynthesis at a rate faster than land plants, trees, and other marine plants.

Algae are also a vital source of food for fish and other marine life, so growing more will help sustain the populations of fish that humans rely on for food.

Algae help combat climate change but can be harmful in some forms

As you learned in the previous section, the alga is a kind of plant that is microscopic and lives in water. Microalgae can take up carbon dioxide that has been released into the air and turn it back into oxygen. This makes algae very good for fighting climate change!

Some types of algae are helpful to plants and animals, but some kinds of algae can be harmful. When large amounts of harmful algae develop in lakes or oceans, this is called a harmful algal bloom (HAB). In HABs, the amount of oxygen drops because the harmful algae are taking it up from the water for cellular respiration—sometimes so much that fish and other marine life cannot survive. Some types of microalgae can also produce toxins that may harm humans if they drink from affected lakes or eat seafood from affected coastal areas.

What are harmful algal blooms?

Harmful algal blooms are large, visible colonies of microscopic algae that live in our nation’s water bodies, especially lakes. The size and duration of these algal blooms can vary greatly. Many scientists who study HABs want to better understand how they form and why they sometimes cause severe problems for living things in the water, from fish to humans.

Harmful algal blooms (HABs) are pretty much exactly as they sound. They are explosive growths of algae that can turn your swimming hole into a chemical waste dump.

Harmful algal blooms cause human health problems, wildlife impacts, and economic loss. There are many types of harmful algal blooms (HABs), including red tides and blue-green algae. HABs contain microscopic organisms called phytoplankton, which is a plant-like organism that lives near the water’s surface and uses sunlight to produce food. When cells of phytoplankton die, they release a toxin that can sometimes be harmful to people, fish, shellfish, and other animals. This is why HABs can have such devastating effects on ecosystems.

Florida algae bloom

When tourists think of Florida, they think of beautiful white sand beaches and aquamarine ocean water. However, these days they may hear more media coverage about an environmental disaster — harmful algal blooms (HABs).

Florida algae bloom is an introduction to what harmful algal blooms are and why they appear in certain places.

Harmful algal blooms are also called HABs (red tides) and can occur wherever water bodies have a high concentration of nitrogen and phosphorus, which can cause excessive plant growth (algae). While some types of algae are beneficial to aquatic life, others produce toxins that are dangerous to humans, fish, and other animals. These blooms can cause extensive economic loss each year through lost fishing revenue, the costs of cleanup, and property damage.

A harmful algal bloom known by scientists as HABs is a rapid increase in algae growth in an aquatic system. HABs are events where the population of algae goes from undetected to noticeable (sometimes very rapidly) in a water body. Basically, it’s when organisms called phytoplankton to grow out of control and make the water look discolored due to the large concentration of algae cells.

What are kelp forests why are they important?

When you think of seaweed, there is a good chance the only thing that comes to mind is the slimy stuff that attaches itself to your swimsuit or worn-down flip-flops. However, seaweeds are an important component of marine ecosystems around the world. Many scientists even consider them as potential allies in our global fight against climate change.

kelp forest of algae
Licence CC

Kelp forests are underwater ecosystems that occur in shallow waters (less than 200 meters deep) on the coasts of continents and islands. They form and grow towards the surface of the water, forming a very dense seaweed forest. Underwater forests like these are important to support underwater life during all its stages of development.

Kelp forests can be found around sea coasts in many parts of the world, notably around New Zealand and Canada. Indeed Britain is one of the few large countries in Europe not to be home to such a forest but its absence should not surprise people.

kelp forests distribution
Maximilian Dörrbecker (Chumwa), CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0>, via Wikimedia Commons
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