Today, we will embark on a journey to explore the mesmerizing, yet increasingly vulnerable
world of coral reefs, where vibrant underwater ecosystems face a multitude of challenges that
demand our immediate attention.
THREAT TO CORAL REEFS
Before we dive into the challenges faced by coral reefs let us know more about coral reefs,
coral reefs are the Earth's most mesmerizing and enchanting realms. These aquatic wonderlands,
often hailed as the "rainforests of the sea," are not only breathtaking in their beauty but also vital
to the health of our oceans and the future of our planet. By building large, complex, robust
colonies, corals literally cement themselves in their environment as not just animals, but as
ecosystem engineers. When many corals grow together, they form reefs. Technically speaking, a
reef is a rigid framework made up of the skeletons of living or once-living organisms that
produce topographic relief, or structure. This structure provides habitat - one of the primary
needs of all living things. Even though coral reefs take up less than 1% of all the ocean floor,
they support over a quarter of all marine species, making them biodiversity hotspots. Many
marine animals rely on coral reefs to find food, to provide habitat and shelter, and to serve as
breeding grounds or nurseries. From pelagic fish like mahi and tuna to small benthic organisms
like lobsters and octopuses, countless marine species rely on coral reefs at some point in their
lives.
Fasinating aren't they but what exactly are coral reefs lets understand,
What are coral reefs?
Corals are invertebrate animals belonging to a large group of colourful and fascinating animals
called Cnidaria. Other animals in this group that you may have seen in rock pools or on the
beach include jelly fish and sea anemones. Although Cnidarians exhibit a wide variety of
colours, shapes and sizes, they all share the same distinguishing characteristics; a simple stomach
with a single mouth opening surrounded by stinging tentacles.
Each individual coral animal is called a polyp, and most live in groups of hundreds to thousands
of genetically identical polyps that form a ‘colony’. The colony is formed by a process called
budding, which is where the original polyp literally grows copies of itself.
Coral are generally classified as either “hard coral” or “soft coral”. There are around 800 known
species of hard coral, also known as the ‘reef building’ corals.
Before we go into the challenges or threats to coral reefs it is very important to understand the
formation of a reef and how corals derive their food.
There is a symbiotic relationship between alge and a coral, the mutually beneficial relationship
between algae and corals which provides algae with shelter and in turn algae gives coral reefs
their colors and supplies both organisms with nutrients, this symbiotic relation began more than
210 million years ago. This symbiotic relationship arose during a time of massive worldwide
coral-reef expansion suggests that the interconnection of algae and coral is crucial for the health
of coral reefs, which provide habitat for roughly one-fourth of all marine life.
Now this algae not only helps in providing food and also being crucial for its health, this algae
also helps a coral to build a skeleton called the reef for the corals which are colonial organisms to
build colonies.
Lets understand how this algae helps a coral build its skeleton, the corals take calcium from its
algae and as all other living organisms exhale carbondioxide corals too exhale carbondioxide but
during the process of building of skeleton the coral combines the carbiondioxide with the
calcium to form a white chalky powder Calcium Carbonate and futher the corals puch
themselves to form a gap and expanding their skeleton in turn expanding the colony. It takes
several years for coral reefs to grow a few centimeters.
IMPORTANCE OF CORAL REEFS
Coral reefs play a very vital role in balancing our ecosystem, as we have understood before that
coral reefs support more that 1/4 th of the marine life, it provides us with abundant of fish
supplies to those who eat sea food and also helps the fishries. Not only it provides us food it also
helps in providing medicines for arthrities, Blood pressure and Cancer, It acts as a barrier which
prevents high water currents, waves and also helps in preventing disasters like floods and
tsunamis.
But recent news says that our coral reefs are in danger, a mass coral bleaching was reported in
the world largest coral reef, the great barrier reef(coral reef belt in australia) which is home to
more than 2,900 coral species.
The reson behind coral bleaching is rise in ocean temperature not only ocean temperature but
there are various other factors which threaten the coral life:
The three major threats are
Climate change
Ocean acidification
Overfishing
CLIMATE CHANGE:
