Every time we look far from the ocean shores, all we can see is endlessly drifting molecules of water. Within those ever drifting molecules, there lies home to almost all the organisms in the marine ecosystems combined. Scientific estimation suggests that 91% of the life in marine ecosystems are yet to be explored. Several species of organisms found in marine ecosystems live in an unimaginably dense environment, but of course, they do not feel the gravity of it, adaptability right?.
Lives of organisms in marine ecosystems largely depends on environmental factors such as salinity, temperature, water density and so on. Even in the absence of fundamental factors, some organisms in marine ecosystems have adapted themselves in extremely harsh environments. Marine ecosystems are home to millions or maybe billions of species from microscopic organisms to world’s largest animal. Marine viruses are one of the smallest life-form found in the marine ecosystems with Blue Whale being the largest animals found in these regions.
In this section, we will talk about several types of organisms found in the marine ecosystems. On a large scale, I have divided organisms based on their sizes and their habitable environment in marine ecosystems. We will also come across some really interesting organisms that had adapted itself to almost every environment in the last thousand or maybe millions of years.
HOW REALLY DIVERSE ARE THE ORGANISMS FOUND IN MARINE ECOSYSTEMS?
Marine ecosystems are home to around 50%-80% of total species found on Earth, both on land and in water. Number of species found in the marine ecosystems lies between 700,00- 1,000,000. A scientific estimation suggests, there are around 33.33%-66.66% of marine organisms that are yet to be discovered in the marine environment. However, there are several species that are currently at risk of their survival. Some of these species are Coral reef fishes, Sharks, Rays, and Marine Turtles.
WHAT ARE THE MICRO-ORGANISMS FOUND IN MARINE ECOSYSTEMS?
Microorganisms in marine ecosystems are found in salty or brackish water of coastal estuaries. They can be single-celled or multi-celled organisms. They can be sub categorised in three parts:
- VIRUSES – Marine viruses are small infectious microorganisms that only replicates into the bodies of other organisms. The origin of these viruses is unknown but it is found that they may have evolved from bacteria.
- PROKARYOTES – These are usually single-celled organisms but can also be found in the form of multicellular organisms. The typical length of Prokaryotic bacteria may vary to few micrometers. Marine bacteria are the most common form of prokaryotic organisms. Prokaryotes including marine bacteria and, marine archaea are normally found in the marine ecosystems.
- PROTISTS – These are the eukaryotic organisms that are not animals, plants or fungus. They are not only different from all other microorganisms but are very diverse in nature. Protists have very organized cells with the nucleus at the center and possess a specialized cellular machinery called as organelles.
WHAT KIND OF PLANT SPECIES ARE FOUND IN MARINE ECOSYSTEM?
Plant species are the lifeline to millions of organisms in the marine environment. Plants inside the marine habitat are usually found in the shallow water. Kelp, Red Algae, Sargassum, and Mangrove are some of the plant habitat found in a marine ecosystem. Plants not only act as food for other organisms but also keeps a proper exchange of oxygen and carbon dioxide in the atmosphere.
- KELP – Kelp, one of the 30 genera of brown algae are found in cold water. This specie grow as a large coastal seawoods. They usually produce algin, a form of carbohydrate which is not only helpful for marine habitat but for industrial purposes also. Kelps are found in abundance and can be as long as 10 feet.
- RED ALGAE – These are one of the oldest groups of Eukaryotic algae that are found in marine habitat but can barely be seen in freshwater. They are one of the oldest photosynthetic organisms found in the marine ecosystems. Red Algae possess minimal structural elements which could be a reason for their extremely small size.
- MANGROVE – The Mangrove is formed when variety of trees and shrubs are found in a wetland in coastal areas such as Estuaries. They provide shelter to several animal offshore species such as shellfish and other shallow water fishes. An ordinary mangrove can grow up to 9 meters. The mangrove leaves are spread from 7 to 15 cms. They constantly protect the shorelines from frequent soil erosion.
WHAT ARE THE ANIMAL SPECIES LIVING IN THE MARINE ECOSYSTEM?
Among all the species living in the marine environment, animal species catches our attention. But, the number of marine species we see without any efforts are just a fraction of animals living in the water. Nekton is one of the few species that can overcome ocean current to comfortably move in the water. Various sea mammals, fishes, and reptiles are some of the family of Nekton group.
- SEA MAMMALS – Every time we hear about marine animals Dolphin, Whale, Shark, Sea Otter are some of the marine mammals that captures our imagination. These are some of the most friendly yet familiar names we have ever heard. These mammals possess an intricate social hierarchy and exhibit impressive intelligence.
- SEA TURTLES – Ever since the time of dinosaurs, sea turtles have gone through several transformations. Banded sea kraits, Leatherback turtle, Kemp’s ridley turtle, Hawksbill turtle are some of the diversification that sea turtles had gone through in the few million years. This species is found in warm and temperate waters and can be found all over the world. The sea turtles usually undergo a long distance migration between their feeding grounds and hatching grounds.
WHAT ARE SOME OF THE ORGANISMS IN THE MARINE ENVIRONMENT THAT ARE AT RISK OD SURVIVAL?
- Sea Snakes
- Marine Turtles
- Sharks and Rays
These are some of many marine organisms that are at risk of their survival in the marine ecosystems. The degradation factors affecting marine habitats including water contamination, ocean currents, salinity, and carbon dioxide. The marine species due to these factors and others are getting degraded at an alarming rate. All round sustainability is what every life form on earth must be demanding right now.
- WHY DO WE NEED TO PROTECT MARINE ECOSYSTEMS AND ITS HABITANTS?
Marine algae alone contribute to most of the oxygen on earth and takes in the huge amount of carbon dioxide, making it favorable to live on Earth.
- WHAT ARE SOME OF THE SALTWATER MARINE ORGANISMS?
Saltwater fish, Clownfish, Saltwater crocodiles, and Corals are some of the examples of saltwater marine ecosystems.