Things we didn’t know about our Aquatic Biome

Photo by Jeremy Bishop

Although I’ve spent nearly twenty three years of my life on this bewitchingly beautiful blue planet, there are so many things that I’m simply unaware of. I’m not talking about rocket science, no; I’m simply talking about the prepossessing story about one of our major biomes of our terrestrial planet, The Aquatic Biome.

A lot of us are vaguely aware of what lakes, ponds & rivers are. We judge them by the size and the depth and occasionally on the flora & fauna around it. But do we really know the difference?

Smaller water bodies such as ponds & lakes belong to the freshwater biome. These ponds & lakes are the remnants of something called the ‘Pleistocene glaciation.’

As we all know, earth is now in the inter-glacial period. Which means, our entire planet is not frozen or covered in thick sheets of ice.

The Quaternary glaciation, also known as the Pleistocene glaciation, is an alternating series of glacial and interglacial periods during the Quaternary period that began 2.58 Million years ago, and is currently ongoing.

Our ponds & lakes that we see today are merely a residue of the glacial period. The animals & plants that thrive in these bodies are adapted to the extremely low salt content present (less than 1%) in these waters.

Photo by Quang Nguyen Vinh

You’d be surprised to know that rivers have high oxygen content and are much cooler at the source of the river than at the mouth.

“But wait Sushanth! I’ve seen a river before! They’re brown and mostly soiled; but definitely not clear. Are you telling me that I don’t know what rivers ar — ”

I’m glad you asked.

Water becomes soiled towards the mouth of the river from all the sediments therefore, less sunlight passes through these waters. Therefore fish that require less oxygen and light are found in these waters such as catfish & carps. A wide variety of ‘heterotrophs’ also thrive here. These heterotrophs are organisms that cannot produce their own food by carbon fixation, therefore they take nutrition from other sources of organic carbon.

If you think this sounds interesting, boy do I have some news. Our Marine biome is rich in diversity with millions of organisms thriving and making their way to become top contenders for being insanely gorgeous.

Did you know that there are these breathtaking places where you can see the tides meet the stream? That’s right. These places are called Estuaries. (seen below).

Photo By National Geographic Society

An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. They are as breathtaking as they seem.

These zones are:

  • Inter-tidal zone
  • Pelagic zone
  • Benthic zone
  • Abyssal zone

I know I’m taking too much of your brain space & throwing out fancy words every now and then; but I’ll explain these as briefly as possible.

It’s a place where the ocean meets land. These areas are somewhat submerged. Waves & tides occasionally come in & out. In these zones, only a handful of species such as algae & molluscs are found. However, the bottom of these inter-tidal zones have invertebrates, a wide variety of fishes & seaweed.

Photo by Tom Fisk

These zones are cold and away from land. These magnificent zones are where you find your favorite animals such as whales, dolphins & surface sea-weed.

The Benthic zone is right below the Pelagic zone. In these areas, sand, silt & dead organisms are usually found. They are nutrient rich and have less light. Species such as bacteria, fungi & sponges are found here.

These zones are extremely cold in temperature. (Around 3 degrees C) and as you might have already guessed, highly pressurized! In these deep parts of the ocean, you can find many species of invertebrates & Chemosynthic bacteria. These bacteria are organisms that use inorganic material as a source of energy and convert them into organic substances.

How cool is that!

I don’t know about you, but I’m pretty blown away as to how little of earth we all know. Our aquatic biome is one of the most beautiful and diverse biomes on the planet. Also did I mention, how gorgeous they are to look at?

There’s still so much to learn all around us. I’m on a journey to do just that! Let’s hope you tag along with me for the ride.


A Front-end Ninja, UI/UX Designer & Author of Being Minimal. More at

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