What is Seaweed?
The word seaweed can refer to both plants and algae. Algae are a separate group of organisms that, like plants, use photosynthesis to convert sunlight, carbon dioxide, and water into glucose (sugars) and oxygen.
The word seaweed can refer to both plants and algae. Algae are a separate group of organisms that, like plants, use photosynthesis to convert sunlight, carbon dioxide, and water into glucose (sugars) and oxygen. Algae, like plants, form the base of the food chain and are found all over the world wherever there is moisture.
They do not have true roots, since they absorb water and nutrients across their entire surface. Nor do they have a developed vascular system for transporting water and nutrients. Algae are important oxygen producers, and more than 50% of the oxygen available to life on Earth comes from algae.
Algal Forms and Growth Habits:
Algae occur in many sizes, shapes, and colors. They are commonly divided into microalgae and macroalgae.
Microalgae consist of a single cell, although they can sometimes form small clusters.
Macroalgae are multicellular; some species are fine and delicate, while others are thick and robust. The largest algae, kelp, can grow up to 70 metres long.
A common way to classify algae is by grouping them based on color. Color depends on the different pigment combinations they use to capture sunlight for photosynthesis. Since different wavelengths of light penetrate to different depths in the water, algae use varying pigments to survive at different depths.
In Sweden, algae can typically grow down to around 20 metres. In clear tropical waters, which are less nutrient-rich and therefore offer greater visibility, algae can grow down to about 200 metres.
Generally:
Green algae live closest to the surface. Brown algae grow slightly deeper. Red algae grow deepest. This is a general pattern—some green algae grow deep, and some red algae grow near the surface.
Some algae live floating in the water column, but most macro algae attach to a solid substrate such as rocks, stones, or even other organisms. Certain species also thrive on boat hulls and piers.
All species have scientific names, but most algae also have common names in many languages. Rockweed and kelp are common names for groups of brown algae. This means rockweed and kelp are not separate from algae—they are specific types of algae.
Algae play crucial roles in aquatic ecosystems:
Primary producers: As the base of the food chain, they provide energy for a wide variety of organisms.
Nutrient uptake: They absorb dissolved nutrients and salts from the water, helping to counteract eutrophication.
Oxygen production: Their photosynthesis produces at least 50% of the oxygen available to organisms on Earth.
Carbon storage: By absorbing carbon dioxide (CO₂), algae contribute to carbon storage and other important ecosystem services.
Habitat creation: Large algae, such as kelp, provide surfaces for many organisms to attach to, offer shelter from predators, and function as nurseries for young animals.
Coastal protection: Extensive beds of algae can dampen wave energy and help bind bottom sediments, reducing coastal erosion.
The word seaweed can refer to both plants and algae. Algae are a separate group of organisms that, like plants, use photosynthesis to convert sunlight, carbon dioxide, and water into glucose (sugars) and oxygen. Algae, like plants, form the base of the food chain and are found all over the world wherever there is moisture.
They do not have true roots, since they absorb water and nutrients across their entire surface. Nor do they have a developed vascular system for transporting water and nutrients. Algae are important oxygen producers, and more than 50% of the oxygen available to life on Earth comes from algae.
Algal Forms and Growth Habits:
Algae occur in many sizes, shapes, and colors. They are commonly divided into microalgae and macroalgae.
Microalgae consist of a single cell, although they can sometimes form small clusters.
Macroalgae are multicellular; some species are fine and delicate, while others are thick and robust. The largest algae, kelp, can grow up to 70 metres long.
A common way to classify algae is by grouping them based on color. Color depends on the different pigment combinations they use to capture sunlight for photosynthesis. Since different wavelengths of light penetrate to different depths in the water, algae use varying pigments to survive at different depths.
In Sweden, algae can typically grow down to around 20 metres. In clear tropical waters, which are less nutrient-rich and therefore offer greater visibility, algae can grow down to about 200 metres.
Generally:
Green algae live closest to the surface. Brown algae grow slightly deeper. Red algae grow deepest. This is a general pattern—some green algae grow deep, and some red algae grow near the surface.
Some algae live floating in the water column, but most macro algae attach to a solid substrate such as rocks, stones, or even other organisms. Certain species also thrive on boat hulls and piers.
All species have scientific names, but most algae also have common names in many languages. Rockweed and kelp are common names for groups of brown algae. This means rockweed and kelp are not separate from algae—they are specific types of algae.
Algae play crucial roles in aquatic ecosystems:
Primary producers: As the base of the food chain, they provide energy for a wide variety of organisms.
Nutrient uptake: They absorb dissolved nutrients and salts from the water, helping to counteract eutrophication.
Oxygen production: Their photosynthesis produces at least 50% of the oxygen available to organisms on Earth.
Carbon storage: By absorbing carbon dioxide (CO₂), algae contribute to carbon storage and other important ecosystem services.
Habitat creation: Large algae, such as kelp, provide surfaces for many organisms to attach to, offer shelter from predators, and function as nurseries for young animals.
Coastal protection: Extensive beds of algae can dampen wave energy and help bind bottom sediments, reducing coastal erosion.