Biodiversity of ocean

“Oceanic treasure is inexhaustible if it is used within carrying capacity…”

Richness of biodiversity of ocean is much more fascinating than the biodiversity of terrestrial rainforest...
“Oceans have many secrets to share with mankind, and species diversity is one of them..”

Oceanic waters have miraculous abilities to generate life. Equally, it is no less fertile than the soil. This is the reason why the biodiversity of ocean is much more fascinating than anything else.

Today, when the terristirial resources are on the verge of depletion, oceanic biotic resources would prove viable alternative for mankind.

To ensure the sustainable use of precious marine treasure, we must have proper understanding about the functioning of marine ecosystem.

Then only, the carrying capacity of biodiversity of ocean might not be compromised; otherwise, the fate of marine ecosystem would not be different than earlier.

For this purpose, let’s understand the nature of marine biodiversity in the layman’s language.

Nature of life in the oceanic waters..

Really, vast fathomless water masses of oceans were the biggest misery before the advent of modern technology.

But, nowadays, it is within the ambit of human capacity due to the explosion of knowledge.

Photic zone

Technically, it is the surface layer of sea water which constitutes around 200 m.

This is the most fertile zone comprising almost 90 percent of marine organisms.

It is called photic duo to the availability of sunlight for photosynthesis.

Apart from this, there are other disphotic and photic zone where sunlight hardly or cannot percolate.

Hence, the aphotic zone of the ocean is known as “Biological deserts.”

Temperature and salinity

Temperature and salinity are the major determinants for the marine organisms. Here, temperature affects the properties of saline water, and in turn, salinity affects the density of sea water creating upwelling and downwelling.

Shell forming animals cannot thrive in the absence of certain level of salinity.

Whereas, temperature determines the dissolution of atmospheric gases in the oceanic water.

In this way,  both are important in making favourable condition for the growth of marine life.

Therefore, smooth functioning of marine ecosystem is directly depends on the optimum level of salinity, as well as temperature.

Marine organisms

Marine ecosystem constitutes vast varieties of species, ranging from microscopic single celled algae to the gigantic whales .

For the convenience of better understanding, these are classified in the three groups according to the location in the sea water.

These groups are -Plankton, Neckton, and Benthos.


Planktons are also called floating organisms including plants and animals. It has two major groups – Phytoplankton and Zooplankton.

Phytoplanktons are autotrophic plants with photosynthetic pigment.

It is the food for marine herbivorous and others. Besides, they are credited for  half of the oceanic oxygen through photosynthesis by using carbon dioxide and sunlight in the photic zone.

On the other hand, zooplanktons are animals which thrive on the Phytoplankton. Plankton includes, algae, protozoas, and other floating animals.


Nektons are labeled as swimmers. These are secondary consumers which thrive on primary consumers zooplanktons. Almost all have backbone.

For example, fishes, reptiles, and dolphins are Nektons. Nektons are the great source of food for human communities.


Unlike other two, benthos live at or near the bottom of the Marine environment.

Such as, crabs, oysters, and octopus are popular benthos which thrive at the bottom of the aquatic environment.

These are also known for theirs recycling abilities of dead materials.

In the Marine ecosystem, these are the three categories of organisms which thrive in the different regions as per theirs abilities.

In order to get insight of the functioning of marine ecosystem, at least a general understanding is highly essential.

This is the natural sequence of biodiversity of ocean.. .


This is the general order of marine ecosystem in which all the Marine communities are inter-related or interdependent.

Functioning mechanism of marine ecosystem

Sun is the primary energy sources for entire environment. In oceanic environment, Phytoplankton as a autotroph, with the help of sunlight and carbon dioxide produces food and precious oxygen for the aerobic organisms.

In this sequence, zooplanktons are primary consumers which graze on the phytoplankton for theirs survival.

The second group is Nekton which consume zooplanktons or even other Nektons.

These are secondary consumers and constitutes large proportion of human food as well. Some of the Nektons are labeled as scavenger too.

Third group is benthos which thrive at the bottom of aquatic environment. Majority of them are decomposers and play important role in the recycling of materials.

At last,

After tentatively understanding the nature and function of biodiversity of ocean, one can easily conclude that there is no dearth of food and other resources in the age old treasure. At the same time, we must not forget that this is the last endowment of nature.

Nowadays, unfortunately, oceans are rapidly becoming the dumping ground for the wide array of waste. It is proved that if it continues, the life in the ocean will not be safe in the near future. So, it is the natural duty of everyone to act as early as possible…

Conjunctions for alternative choices

Adversative coordinating conjunctions

Role of subject complement

Adverbial complements

Corrective measures for bleeding biodiversity

Coral reef ecosystems

Impacts of sea water temperature

Equatorial natural region

Growing cyclones in the Arabian sea

Deforestation and soil erosion

Marine ecosystem