They are also edible and can be used to make kelp lasagne! Another example of a delicious seaweed is nori, also known as laver. Seaweeds are divided into three main groups based on colour: brown, green and red algae. A well-known example of the first group is the giant kelps that form massive and ecologically important forests off the western coast of Canada and the United States.
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It can host a wide variety of algal and animal life. The bright green seaweed in the centre is an alga known as Ulva lactuca, or sea lettuce. Image: Amanda Savoie © Canadian Museum of Nature Tide pools are formed when water is left behind in a depression as the tide goes out. The depth at which they can be found in the ocean is determined by how much sunlight penetrates the water-in clear tropical waters this can be surprisingly deep! Different types of seaweeds found in a tide pool near Point Lepreau, New Brunswick. Additionally, they live in marine environments, such as oceans and estuaries, in the intertidal zone or shallow subtidal zone. So, seaweeds are algae, but what makes them different from other types of algae? The answer lies in two important characteristics: they are macroscopic and marine. Seaweeds are big enough that they can be seen without a microscope. Image: Tobi Bailey © Canadian Museum of Nature Collecting seaweed almost always involves getting your hands and feet wet. Here, Amanda is looking for specimens to bring back to the Museum in the intertidal zone at Kejimkujik National Park, Nova Scotia. This group includes seaweeds, diatoms, dinoflagellates, phytoplankton, cyanobacteria, and many more photosynthetic organisms it does not, however, include land plants, even those that live in lakes and oceans like seagrass or water lilies. They occur in a wide range of sizes: some are tiny single cells, while others such as giant kelp can be more than 45 metres long. Algae are aquatic and can be found almost anywhere that there is water and sunlight. Algae are usually photosynthetic, meaning that they convert light from the sun into chemical energy-carbohydrates like sugar and starch.
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The term “algae” refers to a group of organisms defined by ecological traits. The short answer is that seaweeds are a kind of algae. If that is the case, what are algae? Image: Amanda Savoie © Canadian Museum of Nature But what exactly are these strange organisms? And how do they differ from algae? Waves crashing onto seaweed-covered rocks at low tide in Kejimkujik National Park, Nova Scotia. If you’ve ever spent time by the sea, you’ve probably seen seaweed-either floating in the water, washed up on the beach, or draped over intertidal rocks.