Life and Strife of Coral Reefs

Picture a massive rocklike structure of dazzling colour, submerged in clear blue tranquil water, teeming with exotic plants and animals of all shapes and sizes. Then an enormous school of fish of brilliant colours enter your view. They swim gracefully through the water, some dart to and fro between the reefs while others stop to nibble on a tasty snack. As you carefully study this magnificent scene you notice a manta ray hovering effortlessly near the seabed and a turtle close by grazing on one of the sponges on the reef.

The once massive structure of exuberant colour is now faded and overgrown with slimy plants and macro algae. The desolated reef, now occupied by trash, is no longer a lovely home or feeding ground for fish and other aquatic animals. Dead fish and other wastes can be seen lying on the sea floor. The murky water, filled with unwanted, disgusting waste is no longer a pleasant sight. This is a picture of what a reef could look like in a short period of time if it does not receive proper protection from sources of water pollution. Coral reefs and their eco-systems are being affected by three main sources of water pollution: agricultural runoff, sewage and marine debris.

Corals are the most import part of a reef because of the long lasting structures they build and the homes that these structures provide for countless organisms. Although coral heads resemble plants or rocks they are actually coral polyps. A coral polyp is a tiny fragile limestone-secreting animal. The limestone serves as a skeleton that either is embedded within the living tissue of the coral or encloses the animal (United States Environmental Protection Agency).

Coral reefs are made up of numerous coral colonies and take hundreds or sometimes even thousands of years of growth before becoming a striving coral reef ecosystem. Coral reefs are often called rainforests of the sea because of the diversity of life for which they provide homes and food. ICRIN (International Coral Reef Information Network) have said, As one of the most complex ecosystems on Earth, coral reefs are home to over 4,000 different species of fish, 700 species of coral, and thousands of other plants and animals.

The word ecosystem refers to the relationship that all living and nonliving things have among themselves in an environment. Scientific studies show that the coral reefs are the nucleus of an intricate ecosystem, which is extremely sensitive to environmental disturbances such as various forms of water pollution (United States Environmental Protection Agency).

In the article Water Pollution and Society, David Krantz and Brad Kifferstein point out that coral reefs need special environmental conditions to survive. The conditions needed are special temperatures, saltwater, oxygen, and sunlight. Reef building corals require warm water conditions. Different corals living in different regions can withstand different temperature fluctuations. However, corals generally live in water temperatures ranging from 20 to 32 degrees Celsius (68 to 90 degrees Fahrenheit). Corals also require a balance in the ratio of salt in a corals tissues to the salt water surrounding it. If the coral tissues contain more salt than their environment, the coral will absorb water through tissue membranes causing the coral to expand and bust its limestone skeleton. On the other hand if the coral tissues contain less salt than their environment, the coral will lose water and dehydrate (ICRIN). Corals like other pants and animals need oxygen to live and breath. Lastly corals need to grow in shallow water where sunlight can reach them. Reef corals depend on zooxanthellae (tiny one-celled algae) that grow inside the cells of the coral polyps bodies. The algae use coral waste and carbon dioxide, which the polyps produce during the process of respiration, in making their food. In return, the polyps receive oxygen and nutrients produced by the algae during photosynthesis. When environmental conditions fall outside these requirements, the health of a coral reef community can be severely disrupted (Sylvia A Johnson 21).

Water pollution is the contamination of a body of water or the disruption of its natural processes and environmental conditions. Water pollution upsets these processes, mainly by robbing the water of oxygen. Two main sources of water pollution that affect the water in this manner are agricultural runoff and sewage (World Book 2001).

Agricultural runoff occurs when water runs of farmlands and giant feedlots carrying pesticides, fertilizers and animal waste into nearby waterways. Pesticides are harmful to a coral reef ecosystem because it kills fish and other organisms that absorb large amounts of pesticides into their flesh. The death of these animals will affect the rest of the food chain including the coral reefs.

Sewage is a mixture of water, human waste, and ground-up garbage. The water and human waste contents come from sinks and toilets of homes, restaurants, office buildings, and factories. Water in sewages also originates from bathtubs, showers, dishwashers and laundry washers. Peter Kaminsky, explained in an article entitled Water Pollution that sewage sometime may contain debris due to water runoffs that occur after storms or floods. Kaminsky went on to say that about 80 per cent of all the sewage in the United States goes through treatment plants that remove solids and such dissolved substances as the nutrients nitrogen and phosphorus. About ten per cent passes through septic tanks before being filtered ad seeped into the ground, while the remaining 10 per cent goes untreated directly into rivers, lakes, streams or oceans.

Agricultural runoff, from livestock pens, and untreated sewage flow into waterways and severely affect the physical conditions of the coral reefs. This occurs because untreated sewage and agricultural runoff contain many harmful chemicals and pathogens. Pathogens are microorganisms such as viruses, bacteria, and parasites. Pathogens cause many species to become infected with diseases (United States Environmental Protection Agency). Untreated sewage can also directly affect the coral reef ecosystem by poisoning and killing fish and aquatic plants that feed on the reef. Improper sewage treatment has especially affected coral reefs in the Caribbean and Central America, where statistics show that just 10 per cent of sewage is properly treated before it is dumped in the sea (Keith Hammond).

Sadly, even treated sewage that is dumped in waterways, also harms coral reefs and their ecosystems. Treated sewage and fertilizers affect the coral reefs because they contain very high levels of nutrients such as nitrates and phosphates. Normal quantities of these nutrients help to support various life forms in the water but at excess levels, nutrients over stimulate the growth of aquatic plants and algae. Soon some of the excess algae die because there are not enough herbivorous fish to eat the extra algae. After algae die, they decay and use up dissolved oxygen (Sue Wells & Nick Hanna 79). The loss of oxygen affects the respiration of fish and bottom-dwelling animals that can not survive when levels of dissolved oxygen drop below two to five parts per million. When this occurs, aquatic organisms die in large numbers, which leads to a decrease in animal and plant diversity and a disruption in the food chain. Once the herbivorous fish that kept harmful algae in check are eliminated, algae will overgrow and smother the coral reefs (Krantz and Kifferstein).

Another type of pollution that plagues coral reefs and their ecosystems is marine debris. Marine debris, which includes plastics, fishing nets, and many other forms of trash and garbage, pollute oceans in physical, rather than chemical ways. Marine debris can come from many sources, including ships and other sea vessels, divers, offshore oil platforms, and improper disposal of trash on land (Boyce Thorne-Miller & John Catena19)

Marine debris can affect the coral reef ecosystem in two ways, one killing the coral reefs by continually rubbing against them or smothering them while the other being to harm fish species and other aquatic organisms that use the reef. Marine debris threatens the lives of aquatic organisms by entangling, poisoning, or choking them. This occurs because marine animals mistake floating plastic bags, balloons and other items, which resemble jellyfish, as one of their normal food, sources. When the animals go to feed on the imagined food some may get entangled in the object and die, while others suffocate or become poisoned after trying to digest the debris (Wells & Hanna 88)

Sadly, we learned from Wells and Hanna that a survey in the 1980s found that reef damage had occurred in 93 of the 109 countries with reef and coral communities (6). Recently the ICRIN have stated that over a quarter of the worlds reefs have been destroyed and up to 60 per cent of the reefs may be lost by within our lifetime if we dont take action.

In a UNESCO article on the status of the worlds coral reefs, written by Peter Coles in December 2002, he states that unfortunately the biggest threat to the coral reefs is human. He adds that According to the UNESCO report coral reefs provide goods and services worth an estimated US$375 billion per year (eg fish, tourism, coastal protection, etc), while 500 million people depend totally or partially on reefs that are being damaged. Surely, this being the case shouldnt we all be trying our hardest to keep coral reefs alive?

It is time that people around the world act now before the beautiful rainforests under the sea are sadly no more! Pollution can be avoided and must be avoided if we are to succeed in preserving the worlds coral reefs. In order to succeed in this mission many environmentalists say that people must think globally and act locally. The John Gray Recyclers believe that the plight of the worlds coral reefs is now so serious that we need to not only think globally but act globally as well.

Please join the John Gray Recyclers with our Seacology Foundation project and help to keep the worlds coral reefs healthy. Read more information on our website and then check out all the wonderful projects that the Seacology Foundation does at www.seacology.org

Then please contact us at johngrayrecyclers@hotmail.com