Wednesday, November 20, 2013

The discarded lines abrade coral polyps and upper tissue layers

The discarded lines abrade coral polyps and upper tissue layers. Corals are able to recover from small lesions, but larger and recurrent damage complicates recovery. Bottom dragging gear such as beach seines can damage corals by abrasion and fracturing. A beach seine is a long net about 150 meters (490 ft) with a mesh size of 3 centimeters (1.2 in) Toshiba Satellite A300D CPU Fan and a weighted line to hold the net down while it is dragged across the substrate and is one of the most destructive types of fishing gear on Kenya’s reefs.[12] Bottom trawling in deep oceans destroys cold–water and deep–sea corals. Historically, industrial fishers avoided coral because their nets would get caught on the reefs. HP Pavilion dv8397ea CPU  Fan In the 1980s, "rock–hopper" trawls attached large tires and rollers to allow the nets to roll over rough surfaces. Fifty-five percent of Alaskan cold–water coral that was damaged by one pass from a bottom trawl had not recovered a year later. Northeast Atlantic reefs bear scars up to 4 kilometers (2.5 mi) long. HP Pavilion dv9821ea CPU Fan In Southern Australia, 90 percent of the surfaces on coral seamounts are now bare rock. Even in the Great Barrier Reef World Heritage Area, seafloor trawling for prawns and scallops is causing localized extinction of some coral species. Reefs in close proximity to human populations are subject to poor water quality from land- and marine-based sources. HP COMPAQ TC4200 CPU Fan In 2006 studies suggested that approximately 80 percent of ocean pollution originates from activities on land.[15] Pollution arrives from land via runoff, the wind and "injection" (deliberate introduction, e.g., drainpipes). Runoff brings with it sediment from erosion and land-clearing, SONY Vaio VGN-NW228F CPU Fan nutrients and pesticides from agriculture, wastewater, industrial effluentand miscellaneous material such as petroleum residue and trash that storms wash away. Some pollutants consume oxygen and lead to eutrophication, killing coral and other reef inhabitants.[16] An increasing fraction of the global population lives in coastal areas. HP G62-b16ST CPU Fan Without appropriate precautions, development (e.g., buildings and paved roads) increases the fraction of rainfall and other water sources that enter the ocean as runoff by decreasing the land's ability to absorb it.[16] Pollution can introduce pathogens. HP 580696-001 CPU Fan For example, Aspergillus sydowii has been associated with a disease in sea fans, andSerratia marcescens, has been linked to the coral disease white pox.[16] Reefs in close proximity to human populations can be faced with local stresses, including poor water quality from land-based sources of pollution.[16] HP Pavilion dv6-3049tx CPU Fan Copper, a common industrial pollutant has been shown to interfere with the life historyand development of coral polyps. In addition to runoff, wind blows material into the ocean. This material may be local or from other regions. For example, dust from the Sahara moves to the Caribbean and Florida. HP G42-380LA CPU Fan Dust also blows from the Gobi and Taklamakan deserts across Korea, Japan, and the Northern Pacificto the Hawaiian Islands.[18] Since 1970, dust deposits have grown due to drought periods in Africa. Dust transport to the Caribbean and Florida varies from year to year[19] with greater flux during positive phases of the North Atlantic Oscillation.[20] Toshiba Qosmio G30-167 CPU Fan The USGS links dust events to reduced health of coral reefs across the Caribbean and Florida, primarily since the 1970s.[21] Dust from the 1883 eruption of Krakatoa in Indonesiaappeared in the annular bands of the reef-building coral Montastraea annularis from the Florida Reeftract.[22] Sediment smothers corals and interferes with their ability to feed and reproduce. HP Pavilion dv7-1157cl CPU Fan Pesticides can interfere with coral reproduction and growth. Excess nutrients, particularly nitrogen and phosphorus can cause eutrophication, upsetting the balance of the reef by enhancing algal growth and crowding out corals.This nutrient–rich water can enable blooms of fleshy algae and phytoplankton to thrive off coasts. Compaq Presario CQ40-408AX CPU Fan These blooms can create hypoxic conditions by using all available oxygen. Biologically available nitrogen (nitrate plus ammonia) needs to be below 1.0 micromole per liter (less than 0.014 parts per million of nitrogen), and biologically available phosphorus (orthophosphate plus dissolved organic phosphorus) HP Mini 110-1110ET CPU Fan   needs to be below 0.1 micromole per liter (less than 0.003 parts per million of phosphorus). In addition concentrations of chlorophyll (in the microscopic plants called phytoplankton) needs to be below 0.5 parts per billion.[23] Both plants also obscure sunlight, killing both fish and coral. High nitrate levels are specifically toxic to corals, while phosphates slow down skeletal growth. HP Pavilion dv7-1157cl CPU Fan Excess nutrients can intensify existing disease, including potentially doubling the spread of Aspergillosis, a fungal infection that kills soft corals such as sea fans, and increasing yellow band disease, a bacterial infection that kills reef-building hard corals by fifty percent. A study released in April 2013 has shown that air pollution can also stunt the growth of coral reefs; HP Pavilion dv6-3163eo CPU Fan researchers from Australia, Panama and the UK used coral records (between 1880 and 2000) from the western Caribbean to show the threat of factors such as coal-burning coal and volcanic eruptions. The researchers state that the study signifies the first time that the relationship between air pollution and coral reefs has been elucidated, HP Pavilion dv9740us CPU Fan while former chair of the Great Barrier Reef Marine Park Authority Ian McPhail referred to the report as "fascinating" upon the public release of its findings. Marine debris is any solid object that enters coastal and ocean waters. Debris may arrive directly from a ship or indirectly when washed out to sea via rivers, streams, and storm drains. HP COMPAQ NX9420 CPU Fan Human-made items tend to be the most harmful such as plastics (from bags to balloons, hard hats to fishing line), glass, metal, rubber (millions of tires!), and even entire vessels.[16] Plastic debris kills several reef species. Derelict (abandoned) fishing nets and other gear—often called "ghost nets" because they still catch fish and other marine life despite being abandoned—can entangle and kill reef organisms and break or damage reefs. HP Pavilion dv7-4150ec CPU Fan Even remote reef systems suffer the effects of marine debris. Reefs in the Northwestern Hawaiian Islands are particularly prone to the accumulation of marine debris because of their central location in the North Pacific Gyre. From 2000 to 2006, NOAA and partners removed over 500 tons of marine debris there. HP Pavilion dv5-1102tu CPU Fan Rising sea levels due to climate change requires coral to grow to stay close enough to the surface to continuephotosynthesis. Also, water temperature changes can induce coral bleaching as happened during the 1998 and 2004 El Niñoyears, in which sea surface temperatures rose well above normal, bleaching or killing many reefs. SONY VGN-SZ220 CPU Fan High sea surface temperature (SST) coupled with high irradiance (light intensity), triggers the loss of zooxanthellae, a symbiotic algae, and its dinoflagellate pigmentation in corals, turning coral white. Zooxanthellae provide up to 90% of their hosts' energy supply. Healthy reefs can often recover from bleaching if water temperatures cool. HP Pavilion dv7-6011tx CPU Fan However, recovery may not be possible ifCO 2 levels rise to 500 ppm because concentrations of carbonate ions may then be too low.[26][27] Warming seawater may also encourage an emerging problem: coral disease. Weakened by warm water, coral is much more prone to diseases including black band disease, white band disease and skeletal eroding band. HP Pavilion dv5-1040eb CPU Fan If global temperatures increase by 2 °C during the twenty-first century, coral may not be able to adapt quickly enough.[28] Warming seawater is also expected to cause migrations in fish populations to compensate for the change. ASUS F3Jv CPU Fan This puts coral reefs and their associated species at risk of invasion and may cause their extinction if they are unable to compete with the invading populations.[29] A 2010 report by the Institute of Physics predicts that unless the national targets set by the Copenhagen Accord are amended to eliminate loopholes, then by 2100 global temperatures could rise by 4.2°C and result in an end to coral reefs. IBM ThinkPad R50p 2887 CPU Fan Ocean acidification results from increases in atmospheric carbon dioxide. Oceans absorb around one–third of the increase.[5]The dissolved gas reacts with the water to form carbonic acid, and thus acidifies the ocean. This decreasing pH is another issue for coral reefs.[5] Ocean surface pH is estimated to have decreased from about 8.25 to 8.14 since the beginning of the industrial era,[32] and a further drop of 0.3–0.4 units is expected.[33SONY VGN-CS36GJ/R CPU Fan ] Before the industrial age the conditions for calcium carbonate production were typically stable in surface waters since the carbonate ion is at supersaturated concentrations. However, as the ionic concentration falls, carbonate becomes under-saturated, making calcium carbonate structures vulnerable to dissolution. Toshiba Satellite A215-S4807 CPU Fan Corals experience reduced calcification or enhanced dissolution when exposed to elevated CO 2.[34] Bamboo coral is a deep water coral which produces growth rings similar to trees. The growth rings illustrate growth rate changes as deep sea conditions change, including changes due to ocean acidification. Toshiba Satellite Pro M10-SP405 CPU Fan Specimens as old as 4,000 years have given scientists "4,000 years worth of information about what has been going on in the deep ocean interior". Rising carbon dioxide levels could confuse brain signaling in fish. In 2012, researchers reported on their results after studying the behaviour of baby clown and damselfishes for several years in water with elevated levels of dissolved carbon dioxide, HP Pavilion dv4-1120us CPU Fan in line with what may exist by the end of the century. They found that the higher carbon dioxide disrupted a key brain receptor in the fish, interfering with neurotransmitter functions. The damaged central nervous systems affected fish behaviour and diminishing their sensory capacity to a point "likely to impair their chances of survival".Compaq Presario C550EM CPU Fan The fishes were less able to locate reefs by smell or "detect the warning smell of a predator fish". Nor could they hear the sounds made by other reef fish, compromising their ability to locate safe reefs and avoid dangerous ones. They also lost their usual tendencies to turn to the left or right, damaging their ability to school with other fish. Toshiba Qosmio E15-AV101 CPU Fan Within the last 20 years, once prolific seagrass meadows and mangrove forests, which absorb massive amounts of nutrients andsediment, have been destroyed. Both the loss of wetlands, mangrove habitats and seagrass meadows affect the water quality of inshore reefs.[39] Toshiba Satellite L645D-S4056 CPU Fan Coral mining is another threat. Both small scale harvesting by villagers and industrial scale mining by companies are serious threats. Mining is usually done to produce construction material which is valued as much as 50% cheaper than other rocks, such as from quarries.[40] The rocks are ground and mixed with other materials, like cement to make concrete. Toshiba Satellite A305-S6837 CPU Fan Ancient coral used for construction is known as coral rag. Building directly on the reef also takes its toll, altering water circulation and the tides which bring the nutrients to the reef. The pressing reason for building on reefs is simply lack of space. Boats and ships require access points into bays and islands to load and unload cargo and people. HP Pavilion dv7-4087cl CPU Fan For this, parts of reefs are often chopped away to clear a path. Negative consequences can include altered water circulation and altered tidal patterns which can disrupt the reef's nutrient supply; sometimes destroying a great part of the reef. Fishing vessels and other large boats occasionally run aground on a reef. Two types of damage can result. HP Pavilion dv5-1118es CPU Fan Collision damage occurs when a coral reef is crushed and split by a vessel's hull into multiple fragments. Scarring occurs when boat propellers tear off the live coral and expose the skeleton. The physical damage can be noticed as striations. Mooring causes damage which can be reduced by using mooring buoys. Toshiba Satellite A665-S6050 CPU Fan Buoys can attach to the seafloor using concrete blocks as weights or by penetrating the seafloor, which further reduces damage.[42]Coral in Taiwan is being threatened by the influx of human population growth. Since 2007, several local environmental groups conducted research and found that much of the coral populations are being affected by untreated sewage, an influx of tourists taking corals for souvenirs, HP Pavilion G72-259WM CPU Fan without fully understanding the destructive impact on the coral's ecological system. Researchers reported to the Taiwanese government that many coral populations have turned black in the southeast coast of Taiwan. Potentially, this could lead to loss of food supply, medicinal sources and tourism due to the breakdown of the food chain. HP Pavilion dv6-3109ca  CPU  Fan The global standard for recording threatened marine species is the IUCN Red List of Threatened Species.[44] This list is the foundation for marine conservation priorities worldwide. A species is listed in the threatened category if it is considered to be critically endangered, endangered, or vulnerable. Other categories are near threatened and data deficient. HP Pavilion dv6782eg CPU Fan By 2008, the IUCN had assessed all 845 known reef-building corals species, marking 27% as Threatened 20% asnear threatened and 17% as data deficient.[45] The coral triangle (Indo-Malay-Philippine archipelago) region has the highest number of reef-building coral species in threatened category as well as the highest coral species diversity. SONY UDQF2PH52CF0 CPU Fan The loss of coral reef ecosystems will have devastating effects on many marine species, as well as on people that depend on reef resources for their livelihoods. The Great Barrier Reef is the world's largest coral reef system. The reef is located in the Coral Sea. A large part of the reef is protected by the Great Barrier Reef Marine Park. Toshiba UDQFRPH33CCM CPU Fan Particular environmental pressures include runoff, salinity fluctuations, climate change, cyclic crown-of-thorns outbreaks, overfishing, and spills or improper ballast discharge. Southeast Asian coral reefs are at risk from damaging fishing practices (such as cyanide and blast fishing), overfishing, sedimentation, pollution and bleaching. Toshiba Satellite A505-S6980 CPU Fan Activities including education, regulation and the establishment of marine protected areas help protect these reefs. Indonesia is home to one-third of the world's coral reefs, with coral that covers nearly 85,000 square kilometres (33,000 sq mi) and is home to one-quarter of its fish species. HP Pavilion dv7-2025es CPU Fan Indonesia's coral reefs are located in the heart of the Coral Triangle and have fallen victim to destructive fishing, tourism and bleaching. Data from LIPI in 1998 found that only 7 percent is in excellent condition, 24 percent is in good condition and approximately 69 percent is in poor-to-fair condition. TOSHIBA Satellite L300 CPU Fan According to one source, Indonesia will lose 70 percent of its coral reef by 2050 if restoration action does not occur. In 2007, Reef Check, the world's largest reef conservation organization, stated that only 5% of Philippines 27,000 square kilometres (10,000 sq mi) of coral reef are in "excellent condition": HP G62-a10EJ CPU Fan Tubbataha Reef, Marine Park in Palawan, Apo Island inNegros Oriental, Apo Reef in Puerto Galera, Mindoro, and Verde Island Passage off Batangas. Philippine coral reefs is Asia's second largest. Coral reefs in Taiwan are being threatened by human population growth. Dell MF60100V1-Q000-G99 CPU Fan Many corals are affected by untreated sewage and souvenir-hunting tourists, not knowing that this practice destroys habitat and causes disease. Many corals have turned black from disease off Taiwan's southeast coast. HP Envy 15 CPU Fan,HP Pavilion dv7-1190er CPU Fan,Toshiba Satellite A105-S4074 CPU Fan  

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