We’ve been taught that photosynthesis takes place in plants on land. But does it also happen under water? Indeed, it does. The ocean also experiences photosynthesis. It’s a process that marine organisms do so the ocean can have oxygen and essential nutrients.
To get a clearer picture on how they do it, here’s an explanation on The Process of Photosynthesis in the Ocean. This crucial piece of information will give you more insight on how marine plants and animals thrive in the oceans for so many years already.
What Carries Out the Photosynthesis?
The main organism that is responsible for carrying out photosynthesis in the ocean is phytoplankton. Phytoplankton is often described as very small marine organisms. It is a huge producer for the food web. The phytoplankton is divided into different kinds of groups. All of them contribute to the photosynthesis in the ocean. Here are the common phytoplankton in the ocean:
- Cyanobacteria (Blue-green algae)
- Red Algae
- Green Algae
These phytoplanktons contain the one chemical that is crucial for photosynthesis in the ocean which is chlorophyll. It is used to gain sunlight that enters the water. Phytoplanktons will use photosynthesis to keep the every marine creature in the ocean to stay alive.
Process of Photosynthesis in the Ocean
The marine organisms photosynthesize in a similar way to the plants on land. They will reach for the closest source of sunlight in the open water. Carbon dioxide are also absorbed which are then turned into carbohydrates. Through the complex process of photosynthesis, the organisms will then produce oxygen. Nutrients are also released which other marine creatures can feed on.
Apparently, there are phytoplanktons that contain an additional chemical other than chlorophyll which also helps in photosynthesis. The chemical is called as phycobilins. It is mostly found in red algae, cyanobacteria and dinoflagellates. Phycobilins help other organisms to convert the light that chlorophyll cannot handle.
It can get quite hard for light to pass through into the ocean water. The sunlight is made up of 6 different colours namely violet, blue, green, yellow, orange and red. Unfortunately, not all colours have the ability to pierce into the deep water. The only colours that can get reach the 200 metres depth are green and blue. Meanwhile, the other colours can’t even make it past 100 metres.
That is where phycobilins come to fulfill their role. They phycobilins inside the marine organisms make it easier to absorb any light that is present in the water. They will convert it into the red light that cholorophyll can accept. Photosynthesis can finally occur thanks to the help of phycobilins.
Also read: Importance of Algae in Ocean
Photosynthesis in the ocean faces more challenging aspects in terms of getting enough sunlight and carbon dioxide. Being submerged in water will require the organisms to come closer to the surface of the ocean water. They also absorb nutrients from the ocean water for more energy. A lot of energy is needed for a successful photosynthesis.
Factors that Affect Ocean Photosynthesis
There are some factors that determine the frequency or the intensity of photosynthesis in the ocean. Below are the ones that give the biggest influences to the process:
1. Amount of Nutrients
A high concentration of nutrients is needed for photosynthesis to occur easily. As most of them already exist on the surface of the ocean water, organisms will also carry out photosynthesis there. A lack of nutrients will disrupt the process. Without photosynthesis, the whole marine ecosystem will eventually suffers.
Light is the most important of them all. Without it, photosynthesis is impossible. The higher amount of light that can penetrate the water, the better the photosynthesis is. Dim conditions will cause photosynthesis to slow down.
Seasons will affect photosynthesis. Winter season will provide less light into the depths of water than the summer season. Most photosynthesis will occur on the surface water when it’s winter. In other seasons, the light could reach into deeper parts.
Reportedly, shallow coastal waters experience the most photosynthesis. But this does not exclude other parts of the oceans. Other open oceans also have organisms that carry out photosynthesis though not as intense as the ones in coastal waters.
Characteristics of Plants that Photosynthesize in the Ocean
Plants or algae in the oceans that photosynthesize have specific characteristics. They are special enough to enable adaptation to the harsh condition of the ocean water. The following are the characteristics needed to survive:
- Waxy Leaves and Stems: The wax property helps them to prevent harmful microbes to enter. It also reduces the amount of water that the plants have to take in.
- Long Roots: The plants have long roots or bodies. An example is the brown algae, also known as kelp. The length is meant to help the plant reach the surface of the water. It can also act as a support system for the plant.
- Able to Remove Excess Salt: Some plants are gifted with the ability to get rid of excess salt in their bodies. This ensure that the plant will stay alive.
- Stays Afloat: The plants need to float nearby the sea water surface. It is the best way to get as much sunlight and carbon dioxide for photosynthesis.
- Grow in Shallow Sea Floors: Some plants such as the seagrass can only survive in shallow parts of the ocean. They are one of the places where the sunlight can reach them.
Also read about the different Plants in the Ocean Biome
Photosynthesis in the ocean is vital for the marine ecosystem. It sets the whole system in motion. The ocean is healthy and thriving because of photosynthesis. Our atmosphere is also maintained as harmful gases are absorbed through the process in the ocean.
We must be able to minimise the harm that we are causing to the ocean so that it can continue to function properly.