Marine biome-the biggest and most fascinating

Today, we unfold another episode in our series on biomes, which has been continuing for some weeks. Hope you are not bored in the journey through the world of biomes.

How would you like to visit the biggest and the most fascinating biome in the world? An island nation like ours especially deals a lot with this biome. The marine biome has the ability to fascinate anyone at any time. You are sure to be aware of the fact that the ocean covers about 70 per cent of the Earth. It includes five main oceans: the Pacific, Atlantic, Indian, Arctic and Southern, as well as many smaller gulfs and bays.

We need not tell you about the saltiness of the ocean water, but did you know that there is about one cup of salt per gallon of water in the ocean? The ocean can be divided into three vertical zones - the top layer known as the euphotic zone, the next layer called the disphotic zone and the deepest part of the ocean referred to as aphotic zone or deep sea.

The deep sea comprises 80 per cent of all the habitats on Earth, which makes it the largest habitat on the planet. Did you know that the deepest point in the ocean, the Mariana Trench, is deeper than the total height of Mt. Everest? The Mariana Trench is about 36,200 feet deep.

The climate does not have much of an effect on the marine biome, but the marine biome largely affects our global climate! It provides rain for crops through evaporation, wind to help circulate air and affects coastal temperatures.

The constant motion of the ocean results in currents and waves that may either be warm or cold, depending on the weather and temperature of that area. Temperatures in the ocean range from just around freezing at the pole and in the deep waters, to tropical clear waters that are quite warm.

The average temperature of all oceans is about 39 degrees Fahrenheit. The heat from the sun warms only the surface of the water. Deep down, oceans everywhere are cold and dark.

Over one million species of plants and animals have been discovered in the oceans, and scientists say there may be as many as nine million species we have not found yet. One reason the ocean is very important is for all the algae in it. If it were not for marine algae, we would not be able to breathe!

Through photosynthesis, (the process through which plants produce food) marine plants and algae provide much of the world's oxygen supply and take in huge amounts of carbon dioxide. This absorption of carbon dioxide may be a useful tool in reducing the severity of climate change. One type of marine algae is kelp. Kelp is important because it provides shelter and food for many sea creatures.

Another important marine plant is phytoplankton. These tiny plants serve as food to many of the ocean creatures, from the smallest of fish to large whales. Some scientists estimate that phytoplankton provide the Earth with almost half of its oxygen! Marine plants live in the euphotic zone of the ocean because they need energy from the sun for photosynthesis.

The Earth's oceans are home to most of the planet's biodiversity. Here we can find molluscs, fish, whales, crustaceans, bacteria, fungi, sea anemones and many other animals. Animals have to deal with unique living situations in all zones of the ocean.

The ocean is a salty place that is often cold. Many animals have special adaptations to handle this difficult environment. Most marine mammals have fat to survive in the cold water, but sea otters are unique because they do not have fat. Instead, they have fur more dense than any other mammal, with up to one million hairs per square inch. Most people have ten times less than that on their heads!

The ocean can also support very large life forms. The blue whale is the biggest animal on Earth. It can be over 31 metres long. Blue whales are so large that a small person could crawl through their main arteries, and 20 people could stand on their tongue! Animals in the deep sea also live in a tough environment.

Compiled by Janani Amarasekara