Discover STEM - Aquatic Vegetations

Aquatic Vegetations

How Do They Survive?

What do plants need to survive?

As we know, among the things that plants need in order to live and grow are these:


Carbon Dioxide


But how do aquatic plants get these basic needs if they live underwater?

How do aquatic vegetations get their source of sunlight?

Plants need sunlight to carry out photosynthesis that will produce fuel for the plant’s growth.

Floating plants

Floating plants gets sunlight directly as their leaves are exposed.

Submerged plants

For submerged plants, although sunlight can pass through water, the amount that reaches plants decrease as the depth increase.

To counter this, some plant species have anatomical, cellular or biochemical adaptations that allow them to carry out photosynthesis successfully.

Now, how about carbon dioxide? How do the plants absorb the gas from the water?

For full submerged plants, getting carbon dioxide is more challenging as the gas diffuse slower in water compared to air. Some adaptations that plants have in order to overcome this includes:

Lacks the waxy layer

Lacks the waxy layer on the leaves to ease carbon dioxide absorption.

Having smaller leaves

Having smaller leaves making it easier to absorb carbon dioxide.

Do aquatic plants obtain water from their environment in similar way to terrestrial plants?

Roots, which normally play a very important role in the absorption of water, are often reduced and their main function is anchorage.

Truly aquatic plants absorbs water all over the plant surface, thus there is no need for a highly developed root system.

How important are aquatic vegetation for other aquatic organisms and ecosystem?

Other aquatic organisms

  • Important components of estuarine systems
  • Shelter and habitat for many organisms
  • Food source for aquatic organisms


  • Absorb nutrients, which can be major estuarine pollutants
  • Photosynthesis adds dissolved oxygen to the water, and their leaves and roots help stabilize the shoreline against erosion
  • Maintain the vialibility of the ecosystem

Why don’t you try and make your own indoor water garden?

What we’ll need is..

AQUARIUM of any size which suits our ‘garden’.

AQUATIC SOIL of any type with the right amount for our ‘garden’.

AQUATIC PLANTS of your choice.

AQUATIC ANIMALS which suits our water garden.

All of the items above depends on the size of the aquarium.
Make sure to have source of light for your aquarium too!

Want to see an aquatic plant and learn about its function in a biosphere? Come and find out at Petrosains!

Biosphere – A global ecosystem composed of living organisms and nonliving factors from which energy and nutrients are derived.