HUMAN IMPACTS ON CORAL REEFS

DIFFERENT HUMAN IMPACTS

REEF WALKING

OVER FISHING

CORAL SOUVENIR

BLAST FISHING

SEWAGE

AGRICULTURE◦ (Sedimentation)

◦ (Fertiliser/Pesticide)

This is the practice whereby people step unto the corals, mostly while site seeing of marine organisms

This is mostly done by tourist

By stepping unto the corals, it damages or even kills the coral polyps which are the basic foundation of corals

Overfishing is one driving pressure that has had devastating impacts on coral reefs.

Overfishing is also a damaging problem to many coral reefs around the world.

Overfishing has caused a shift in the reef ecosystem. Overfishing of certain species near coral reefs can easily affect the reef's ecological balance and biodiversity.

A domino effect comes into play when overfishing occurs in or around a coral reef. This is where the over exploitation of one species can cause a collapse in the entire food web.

This is the whereby pieces of corals are broken for there to be made into souvenirs

Coral's many colours give it appeal for necklaces and other jewellery

In the process of doing this it kills the corals and it damages the natural ecosystem

Blast or dynamite fishing is the practice of using explosives to stun or kill schools of fish for easy collection.

This often illegal practice can be extremely destructive to the surrounding ecosystems, as the explosion often destroys the underlying habitat (such as the coral reef) that supports the fishes.

The frequently improvised nature of the explosives used also means danger for the fishermen as well, with accidents and injuries.

Sewage is refuse (rubbish) liquids or solid waste matter. It is often high in nutrients.

Through improper sewage storage and treatment facilities the sewage can leak out into the soil and then become run-off on to the reef.

Through old septic tanks that have not been maintained and cleaned regularly, the sewage can overflow from the tank and find its way on to the reef.

The sewage can be high in nutrients that promotes plant growth. When this happens sea weeds and algae would outgrow corals and the corals would not be able to get enough sunlight so eventually they die.

Agriculture could affect the coral reef in two ways:

◦ Sedimentation

◦ Excessive nutrients via fertilisers/pesticides

Lands are cleared for agricultural crops so there fore the top soil is exposed.

When the rain falls sediments are washed into the reef through rivers and water channels.

This further affects the corals in two ways:◦ The sediment drastically reduces the amount of

light reaching coral reef prevent them from carry out photosynthesis effectively.

◦ As the sediment settles, it can bury corals or cause them to expend a large amount of energy keeping their surfaces clean.

According to the agricultural practiced used, fertilisers/pesticide are sometimes included, this is high in nutrients

In time, leaching can occur and runoff from rains can transport the chemicals into the water ways and eventually the corals reefs through rivers and water channels.

This causes an over growth in seaweed, eventually killing the corals.