How Are Coral Reefs Formed.docx
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How Are Coral Reefs Formed?Coral reef formation involves a variety of processes operating at different spatial scales, and our discussion of how coral reefs are formed reflects that reality.The Philippines is part of the Coral Triangle, the epicenter for marine biodiversity and what is considered the Amazon of the Sea. It is an area with more species of fish and corals than any other marine environment on earth Last year, Reef Check, an international organization assessing the health of reefs in 82 countries, stated that only five percent of the country's coral reefs are in "excellent condition." These are the Tubbataha Reef Marine Park in Palawan, Apo Island in Negros Oriental, Apo Reef in Puerto Galera, Mindoro, and Verde Island Passage off Batangas.How Are Individual Reefs Built?The structural foundation of individual coral reefs is formed by a multitude of marine animals and plants through the processes of slow accumulation and deposition of calcium carbonate (limestone) extracted from seawater.The Main Reef BuildersWhile a wide variety of marine life ultimately contributes to the structural complexities of coral reefs, most of the reef's underlying solid framework is constructed by just a few types of marine organisms.These are the hard (Scleractinian) corals, and the coralline red algae that grows upon and amidst the coral colonies.encrusting coralline algae grows upon a reef surface Coralline algae. Courtesy NOAA Shallow marine waters are rich in calcium (Ca++) and bicarbonate (HCO3-) ions.Hard corals and coralline algae are able to extract these raw materials from sea water, and both types of marine life have the ability to combine them to form calcium carbonate (CaCO3).This substance, also known as limestone, is used to fashion the protectecive outer skeletons of coral polyps as well as to harden the fleshy parts of the coralline algae.After the individual organisms die, they leave behind their limestone skeletons. Over time, the accumulated and compacted minerals contained in the multitudes of these skeletal remains become the large, solid structures we call coral reefs.The overall reef-building process is slow; coral reefs are built over decades and centuries - not weeks or months.
Other Reef BuildersA great variety of other organisms - including many types of invertebrate animals - assist the two primary types of reef builders (discussed above) in the reef-building process by depositing lesser amounts of carbonate particles.These minor contributors include sponges, octocorals ("soft" corals), fire corals, and many other types of invertebrates. Individually, the contribution of each of these groups may be comparatively small, but collectively their contribution can sometimes be substantial.How Are Coral Reef Ecosystems Formed?At the broader spatial scale of the entire reef ecosystem, structure and formation is shaped not only by the dominant animals and plants. Rather, interactions among a host of other abiotic ("physical") factors AND the underlying geology of the area also come into play. In fact, these physical factors usualy represent THE dominant influences on large-scale reef structure.WHAT IS AN ECOSYSTEM? - Here, we define "coral reef ecosystems" as large, interactive areas of coral reef development containing many individual reefs and associated habitats (e.g., seagrass meadows). These ecosystem extends from the shorelines of tropical islands and coasts to the deep blue waters of the open sea, and includes all the marine life within the area as well as the non-living parts of their environment.Most notably, such factors include sea floor depth profile, substrate composition, water movement, light penetration, and other variables that affect hard coral species distribution, growth forms, and abundance.Types of Coral ReefsMost reef scientists generally recognizethree MAJOR typesof coral reefs:Fringing Reefs,Barrier Reefs, andAtolls. Fringing Reefs (Shore Reefs) Fringing reefs are reefs thatgrow directly from a shore. Fringing reefs surrounding Pacific islands Barrier ReefsBarrier reefs areextensive linear reef complexesthat parallel a shore, and are separated from it bylagoon.
Atoll is a roughly circular (annular) oceanic reef system surrounding a large (and often deep) central lagoon.Indo-Pacific atolls
How are coral reefs destroyed?Coral Reefs are fascinating and mysterious ecosystems. They have been around for over five hundred million years and are considered the marine equivalent of tropical rainforests. Covering only 2% of the ocean bottom, they are the home to 25% of all marine species.Unfortunately this underwater paradise is slowly being destroyed. Destructive actions such as the practice of uncontrolled, destructive fishing methods, oil spills, pollution (from domestic and industrial wastes, fertilizers, and pesticides), anchor damage, untreated or improperly treated sewage, and land runoffs are serious threats to the delicate reefs. Fine sediment-like silt is also extremely harmful to corals. This kind of sediment clouds the water and cuts down the amount of light that reaches the coral. Global Warming. Global Warming causes significant temperature increases in waters in which corals inhabit. Suggestions concerning our reefs.Even though a lot is beeing done to protect our coral reefs they are still in trouble, primarily from too many visitors. Various proposals to alleviate the situation have been made such as,limit access:Limiting access to the coral reefs is a very good idea but it would be very difficult to enforce. Considering that anyone can access the parks at any time since they have entrances from all sides. This is nearly impossible to control.rotate reefs:This proposal has never been tried. Giving it a try would mean that heavily impacted reefs would have to be closed for an indifinate time to give it time to recover while visitors visit other reefs wich might be smaller.The needed time to recover is unknown and these smaller reefs might not withsatand the pressure.prohibit diving.Diving and snorkeling are two of the major factors contributing to the deterioration of the coral reef. These activities can be prohibited for several years until the coral reef recover.Glass bottom boats will stil be allowed to give tours of the reefs but only those which are part of the park. Other boats outside of the area will be prohibited to enter the park.restrict diving:Experts strongly beleive that scuba diving and snorkeling are the activities that put the coral reefs to danger the most. Prohibiting private snorkeling and scuba diving would really help. Only allowing these activities to occur from dive boats where divers could be closely supervised. This can be a very effective solution.close the parks:Fullclosure of the parks would be a very drastic step and should be considered only as a last resort. This step will be taken only if every other option fails.None of the suggestions given concerning human contact on the reef will alleviate the problem if the problem of poluted water is not alleviated also. If all of us do not cooperate, soon there will not be reef to save. Time is running out.