Why are mineral accretion Biorock reefs needed? How much faster does coral grow with mineral accretion? How do Biorock reefs compare with conventional artificial reefs? How is a Biorock reef built? What materials are used in a Biorock reef? How are Biorock reefs powered? How do you anchor a Biorock reef? Where do the corals on a Biorock structure come from? How are the corals attached? What happens after the coral fragments are attached?
Will natural corals settle and grow on Biorock structures? Are fish and other marine creatures attracted to Biorock reefs? Why do corals grow faster on a Biorock structure? Does mineral accretion improve coral health? Have mineral accretion results been documented? Do Biorock reefs require maintenance? What is the lifespan of a typical Biorock reef? Could a shipwreck become a Biorock reef? Do old car and truck tires make good artificial reefs? Where are Biorock reefs in operation?
Where are the most exciting Biorock projects? How far off shore can one place a Biorock reef? How deep beneath the surface of the water can one place a Biorock reef structure? Can coral calcium pills be good for you and for coral reefs? Why does the Biorock solution cease to work when the electricity is removed. Why does the algae growth bloom? Would wind technology on the seas offer a better source of power than solar panels, which can get corroded more easily?
As the Biorock wire structure calcifies, what happens to the salinity of the surrounding waters? Is limestone or Biorock an atmospheric CO2 sink?
What does a typical Biorock project cost and how do you calculate the budget? Why won't big international NGOs support effective coral reef restoration?
Questions specific to global warming:. What is an immediate effect due to global warming we are experiencing today? What prevents the CO2 gases from leaving the atmosphere? What might Average Joe not know about global warming that may change his apathetic attitude to the topic?
What are some other methods you might suggest to those environmentally conscious people who wish to preserve our coral reefs for our progeny? Have we seen any examples of a destroyed coral reef eco-system and its effects on the community? How long will it take for global warming to take its toll on this valuable eco-system? Have you seen any other hazardous effects global warming has had on any other marine life eco-systems? Are there any immediate solutions to the problem at hand? We primarily focus on coral reef restoration, marine diseases and other issues caused by global climate change, environmental stress and pollution.
The electrical current causes minerals that are naturally dissolved in seawater to precipitate and adhere to a metal structure. The result is a composite of limestone and brucite with mechanical strength similar to concrete.
Derived from seawater, this material is similar to the composition of natural coral reefs and tropical sand beaches. Invente d by architect Wolf Hilbertz for construction purposes, mineral accretion has been applied to coral reef restoration by Hilbertz and coral scientist, Tom Goreau. Mineral accretion structures can be built in any size or shape. This patented process increases the growth rate of corals well above normal, giving them extra energy that allows them to survive in conditions that would otherwise kill them.
At the same time these structures attract huge numbers of fish, and also provide breakwaters that get stronger with age. Biorock reefs, with their lush coral swarming with fish, have become major ecotourism attractions. Hotels in the Maldives, Indonesia, and Panama have built their advertising around the fact that they can offer great snorkeling right in front of their beaches. Reefs die for many reasons: rising water temperatures, sewage, eutrophication, disease and negligence.
A reef ecosystem that took hundreds of years to grow can be destroyed in a single afternoon by dredging, dynamite or cyanide fishing. Corals around the world have been severely affected by global warming. If it remains too hot for too long, the corals die of heat shock. Record high temperatures are killing corals across the globe, with only a few of the hardiest corals surviving. Mineral accretion has proved to be a remarkable new method that increases coral growth rates and their ability to resist environmental stresses.
When coral reefs die, fish populations disappear; beaches and shorelines are damaged. Unprotected by breakwaters, fragile land areas become vulnerable to erosion, saltwater intrusion and destruction from waves. For an already damaged reef, regeneration is very slow taking several decades, even under ideal conditions. Global warming has caused significant reef mortality around the world. The prognosis is that oceans will continue to warm until world leaders recognize the long-term consequences of turning a blind eye to the problem.
A few governments have tried to address the problem by building sea walls out of concrete, steel, coral rubble or sand bags. But these materials soon rust, corrode, collapse and need to be rebuilt.
In contrast only breakwaters and reefs made of mineral accretion can provide permanent, cost-effective protection capable of keeping pace with rising global sea levels. Mineral accretion growth rates are typically from one to several centimeters of new rock per year, depending on the surface area of the structure.
The rate at which the coral grows depends on the amount of current, the size of the structure and the species of coral.
Typically, growth rates are about 3 to 5 times faster than normal. Artificial reefs are typically made from manmade materials like sunken ships, planes, cars, concrete, rubber tires and trash. On land, this material might be called junk. Although fish will hide behind or within any structure that provides shelter and although certain sponges and soft organisms will sometimes settle on these materials, they never turn into a true coral reef.
To build a Biorock reef, an electrically conductive frame, usually made from readily available construction grade rebar or wire mesh, is welded together, submerged and anchored to the sea bottom.
Sizes and configurations are infinite and are varied to fit the setting. A low voltage direct current is then applied. Power sources can include chargers, windmills, solar panels or tidal current generators. To see how this is affecting global reef health, Kay Davis at Southern Cross University in Lismore, Australia, and her colleagues analysed data from 36 coral reef sites in 11 countries, including the Great Barrier Reef in Australia and Shiraho Reef in Japan.
They found that the rate at which coral reefs are depositing new calcium carbonate has been dropping by around 4 per cent per year since If this trend continues, a tipping point will be reached in the year whereby corals stop growing altogether and their calcium carbonate structures start to dissolve away into the ocean.
Foliaceous corals, such as the pagoda coral Tubinaria mesenterina, are scroll-like in their appearance. Finally, solitary coral polyps that do not form colonies may be referred to as free-living. Solitary species include the mushroom coral Fungia scutaria species. Coral growth rates C oral growth rates are highly variable between species. In optimum conditions in the tropics, some coral species, such as the branching Acropora cervicornis, can display fast growth rates of between cm per year while other species, such as Porites, grow much slower at around 1 cm per year.
In cold-water environments, the annual growth rates of corals are especially slow. For example, the annual growth rate for Oculina varicose is estimated at around 1. The growth rates of all coral species are heavily influenced by environmental conditions and can slow dramatically in response to disease and environmental disturbances including changes in ocean chemistry salinity and acidification , rising ocean temperatures, sunlight and sedimentation.
Coral reef structures D epending on their structural characteristics, coral reefs are generally described using three major reef types: 1 Fringing reefs , the most common type of the reef forms, extend seaward from the shore, sometimes separated by a narrow stretch of water or lagoon.
They are generally found in shallow waters with the reef flats becoming exposed during low water. Barrier reefs are frequently formed by a network of individual reef systems, often encompassing fringing reefs extending from offshore islands. Sometimes a part of a colony breaks off and forms a new colony. This is called fragmentation, which can occur as a result of a disturbance such as a storm or being hit by fishing equipment. In sexual reproduction, eggs are fertilized by sperm, usually from another colony, and develop into a free-swimming larva.
There are two types of sexual reproduction in corals, external and internal. Depending on the species and type of fertilization, the larvae settle on a suitable substrate and become polyps after a few days or weeks, although some can settle within a few hours! Most stony corals are broadcast spawners and fertilization occurs outside the body external fertilization. Colonies release huge numbers of eggs and sperm that are often glued into bundles one bundle per polyp that float towards the surface.
Spawning often occurs just once a year and in some places is synchronized for all individuals of the same species in an area. This type of mass spawning usually occurs at night and is quite a spectacle. Some corals brood their eggs in the body of the polyp and release sperm into the water.
As the sperm sink, polyps containing eggs take them in and fertilization occurs inside the body internal fertilization. Brooders often reproduce several times a year on a lunar cycle.
The largest polyps are found in mushroom corals , which can be more than 5 inches across. But because corals are colonial, the size of a colony can be much larger: big mounds can be the size of a small car, and a single branching colony can cover an entire reef. Reefs, which are usually made up of many colonies, are much bigger still.
The largest coral reef is the Great Barrier Reef , which spans 1, miles 2, km off the east coast of Australia. It is so large that it can be seen from space! Reefs form when corals grow in shallow water close to the shore of continents or smaller islands. The majority of coral reefs are called fringe reefs because they fringe the coastline of a nearby landmass.
But when a coral reef grows around a volcanic island something interesting occurs. Over millions of years, the volcano gradually sinks, as the corals continue to grow, both upward towards the surface and out towards the open ocean.
Over time, a lagoon forms between the corals and the sinking island and a barrier reef forms around the lagoon. Eventually, the volcano is completely submerged and only the ring of corals remains.
This is called an atoll. Waves may eventually pile sand and coral debris on top of the growing corals in the atoll, creating a strip of land. Many of the Marshall Islands, a system of islands in the Pacific Ocean and home to the Marshallese, are atolls. It takes a long time to grow a big coral colony or a coral reef, because each coral grows slowly. The fastest corals expand at more than 6 inches 15 cm per year, but most grow less than an inch per year.
Reefs themselves grow even more slowly because after the corals die, they break into smaller pieces and become compacted. Individual colonies can often live decades to centuries, and some deep-sea colonies have lived more than years. One way we know this is because corals lay down annual rings, just as trees do. These skeletons can tell us about what conditions were like hundreds or thousands of years ago. The Great Barrier Reef as it exists today began growing about 20, years ago.
There are also deep-sea corals that thrive in cold, dark water at depths of up to 20, feet 6, m. Both stony corals and soft corals can be found in the deep sea. Deep-sea corals do not have the same algae and do not need sunlight or warm water to survive, but they also grow very slowly.
One place to find them is on underwater peaks called seamounts. Reefs are the big cities of the sea. They exist because the growth of corals matches or exceeds the death of corals — think of it as a race between the construction cranes new coral skeleton and the wrecking balls the organisms that kill coral and chew their skeletons into sand. When corals are babies floating in the plankton, they can be eaten by many animals.
They are less tasty once they settle down and secrete a skeleton, but some fish, worms , snails and sea stars prey on adult corals. Crown-of-thorns sea stars are particularly voracious predators in many parts of the Pacific Ocean.
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