Article:

Coral Reefs:

What is Biodiversity?

Biodiversity also refers to the number or abundance of different species of life in a given area. This shows the wealth of biological resources at our disposal. It is about preserving natural area, made up of a community of plants, animals and other living things that is constantly diminishing as we plan for human activities that diminish due to habitat destruction .

Bioerosion:

Organism that degrade the calcarious substance therefore, bioerosion means the degradation caused by the activity of plant and animal organisms, which creep into the subsoil or erode its surface.

Bio-erosion occurs naturally in nature, but if too much can damage the environment. This natural phenomenon is important to geologists and paleontologists because it allows them to determine prehistoric water levels, climates, and evolutionary patterns.

Example of Bioerosion:

An example of Bioerosion can be seen in the case of coral reefs. Corals create limestone (or calcium carbonate) to form their skeleton, which serves as a source of food and shelter for reef organisms. Microborers and organisms that graze on the surface of the limestone slowly break down the reef skeleton.

                                                           Figure no. 1 Coral reefs

Biodegradation or bioerosion is the removal of calcium carbonate substrates by biological agents1. Corals accumulate calcium carbonate, or limestone, to form their skeletons. Coral skeletons are the structures that provide food and shelter for most coral reefs. Corals regularly accumulate calcium carbonate, but biota naturally break down calcium carbonate, producing debris and sand. The balance between accumulation and erosion is delicate. When bioerosion becomes excessive, corals die faster than they can grow, and corals cannot keep up with the bioerosion caused by rising sea levels.

Bioeroders:

The biodegradable community or bioeroder consists of many types of animals, plants, and even bacteria. They eat coral skeletons, usually dead coral, either by mechanically removing calcium carbonate, which contains tooth-like structures or by chemically excreting acidic compounds and dissolving the coral skeleton. Biodegradable material has three main functional groups: microborers, macroborers and herbivores.

Microborers:

Microborers are tiny algae, cyanobacteria and fungi think so, you'd be wrong In Australia microborers destroy about 0 35kg of calcium carbonate per square meter per year 3. If this figure is accurate for the entire reef, microborers alone can produce enough sand to fill 1.1. million school buses in one year!

Grazers:

Grazers are animals that scrape the surface of the coral skeleton. These animals consume algae that grow on the surface of the skeleton (some fish even eat live coral) and eventually scrape away the lime. The carbonate when they try to eat these scratches changes the surface of the framework which affects the natural processes, such as water exchange, in the reef. Georgian shepherds are animals that scrape the surface of the coral skeleton. Grazers  are mainly thistles and fish. These animals consume algae that grows on the surface of the skeleton (some fish even eat live coral) and when they try to eat it, it breaks down into calcium carbonate. These ripples change the surface of the reef and affect natural processes, such as water exchange, on the reef.

Importance of Bioerosion:

The coral reef framework provides many goods and services to not only the organisms on the reef, but to humans as well. Bioerosion weakens the coral skeletal framework  reducing the mechanical stability of the reef.  Coral reefs have the ability to absorb up to 90% of energy from wind-driven waves4 , protecting the shoreline and coastal property. If the skeleton is weakened then storm events and tsunamis will be much more destructive.  Erosion can also alter the structural complexity of coral reefs and this complexity provides shelter for fish, crabs, and other invertebrates.  If there is less shelter available for these animals then there will be less fish, crabs, and shrimp for us to eat. Finally, if bioerosion is excessive and erodes at a faster rate than corals accrete, coral reefs will not be able to keep up with sea-level rise.

Damages to Coral reef:

Overfishing: 

Increasing demand for food fish and tourism curios has resulted in over fishing of not only deep-water commercial fish, but key reef species as well. Overfishing of certain species near coral reefs can easily affect the reef's ecological balance and biodiversity. For example, overfishing of herbivorous fish can also lead to high levels of algal growth. From subsistence level fishing to the live fish trade, inadequate fisheries management is forcing the decline of fish stocks. Choose seafood products that come from certified, well-managed and sustainable fisheries. Certified products are available at most supermarkets - check out the product

Fishing using dynamites:

Fishing using dynamites, cyanide and other methods that damage fragile coral reefs is highly unsustainable. Explosives and cyanide stun fish, making them easier to capture. Fishermen say they have no choice if they are to compete with trawlers and overcome declining fish supplies caused by past overfishing. These practices often do not select or target specific fish species and often result in the death of young fish in the process. The destruction of coral reef habitats that fish rely on also reduces the productivity of the area and has a greater impact on the livelihoods of fishermen.

Unsustainable tourism:

Tourism generates vast amounts of income for host countries. Where unregulated however, tourism pressures can cause damage to the very environment upon which the industry depends. Physical damage to the coral reefs can occur through contact from careless swimmers, divers, and poorly placed boat anchors. Hotels and resorts may also discharge untreated sewage and wastewater into the ocean, polluting the water and encouraging the growth of algae, which competes with corals for space on the reef.

Pollution:  

Coral reefs need clean water to grow. Pollution, from trash to waste oils, is damaging rocky reefs around the world. Pollution from human activities on land can damage coral reefs when carried by rivers to coastal waters. Do your part - don't leave litter or throw away unnecessary items on beaches, in the sea or near storm drains.

Global Aquarium Trade:

It is estimated that almost 2 million people around the world own marine aquariums. The overwhelming majority of marine aquariums are stocked with wild-caught species. This rapidly growing trade leads to the trans-regional movement of exotic fish species. the use of carbon in collection, the overexploitation of host organisms and the high levels of mortality associated with poor animal husbandry practices and non-susceptible nature. According to estimates, nearly 2 million people worldwide have marine aquariums. The vast majority of marine aquariums are stocked with wild-caught species. This rapidly growing trade leads to the trans-boundary movement of charismatic fish species. Trade-related threats include the use of cyanide during harvest, overexploitation of target organisms, and high mortality associated with poor husbandry practices and insensitive transportation. There are regulations that encourage the use of sustainable collection methods and raise industry standards.