{"id":295143,"date":"2024-05-10T19:00:27","date_gmt":"2024-05-10T13:30:27","guid":{"rendered":"https:\/\/forumias.com\/blog\/?p=295143"},"modified":"2024-05-11T14:57:24","modified_gmt":"2024-05-11T09:27:24","slug":"fifth-mass-coral-bleaching-event","status":"publish","type":"post","link":"https:\/\/forumias.com\/blog\/fifth-mass-coral-bleaching-event\/","title":{"rendered":"Coral Bleaching- Explained Pointwise"},"content":{"rendered":"

Researchers at the ICAR-Central Marine Fisheries Research Institute have found that marine heatwaves since October 2023<\/span> have resulted in widespread bleaching of coral reefs in the Lakshadweep Sea<\/span>. Further, according to the US National Oceanic and Atmospheric Administration<\/span> (NOAA<\/span>), the fourth global mass coral bleaching event<\/span> has been triggered by extraordinary ocean temperatures<\/span>. The mass coral bleaching could have serious consequences for ocean life and millions of people who rely on reefs for food<\/span>, jobs<\/span>, and coastal defence<\/span>.<\/p>\n

\"Coral
Source- NOAA<\/figcaption><\/figure>\n\n\n\n\n
Table of Content<\/strong><\/td>\n<\/tr>\n
What are coral and coral reefs?<\/a>
\nWhat is the significance of Corals?<\/a>
\nWhat is coral bleaching? What are the mass coral bleaching events which have taken place?<\/a>
\nWhat are the Causes Responsible for Coral Bleaching?<\/a>
\nWhat are the consequences of coral bleaching?<\/a>
\nWhat are the Initiatives to Protect Corals?<\/a>
\nWhat should be the way forward?<\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

<\/a>What are coral and coral reefs?<\/strong><\/span><\/h2>\n

Corals-<\/strong>\u00a0Corals\u00a0are small\u00a0(0.25-12 inches), soft-bodied marine invertebrates (not possessing a spine) which\u00a0belong to the group cnidaria<\/span>. These are\u00a0sessile animals<\/span>\u00a0which permanently attach themselves to the ocean floor.<\/p>\n

Each individual coral animal is known as a\u00a0polyp\u00a0<\/span>and it lives in groups of hundreds to thousands of genetically identical polyps that form a \u2018colony<\/span>\u2019. They\u00a0use their tiny tentacle-like hands to catch food<\/span> from the water\u00a0and sweep into their mouth.<\/p>\n

Mutualistic relation between Corals and Algae-<\/strong>\u00a0These coral polyps have\u00a0microscopic algae called zooxanthellae\u00a0<\/span>living within their tissues. The corals and algae have a mutualistic relationship.
\nThe coral\u00a0provides the zooxanthellae with\u00a0the compounds\u00a0necessary for photosynthesis<\/span>. In return, the\u00a0zooxanthellae supply the coral with organic products<\/span> of photosynthesis, like carbohydrates<\/span>, which are\u00a0utilized by the coral polyps\u00a0for\u00a0synthesis of their calcium carbonate<\/span> skeletons. In addition to providing corals with essential nutrients,\u00a0zooxanthellae<\/span> are responsible\u00a0for the\u00a0unique and beautiful colours of corals<\/span>.<\/p>\n

Types of Corals-\u00a0<\/strong>There are two types of corals- Hard coral and soft coral.<\/p>\n

a. Hard corals-<\/strong>\u00a0These corals also called\u00a0hermatypic<\/span>\u00a0or \u2018reef building<\/span>\u2019 corals which extract\u00a0calcium carbonate from the seawater<\/span>\u00a0to build\u00a0hard<\/span>,\u00a0white coral exoskeletons<\/span>.<\/p>\n

b. Soft Corals-<\/strong>\u00a0Soft corals borrow their appearance from plants, and attach themselves to such skeletons and older skeletons built by their ancestors. Soft corals add their own skeletons to the hard structure over the years and these growing multiplying structures gradually form coral reefs. They are the\u00a0largest living structures on the planet<\/span>.<\/p>\n

Coral Reefs in India-<\/strong>\u00a0Coral reefs in India are located in seven regions namely\u00a0Goa coast<\/span>,\u00a0Kerala coast<\/span>,\u00a0Palk Bay<\/span>,\u00a0Gulf of Kutch<\/span>,\u00a0Gulf of Mannar<\/span>,\u00a0Lakshadweep islands<\/span>\u00a0and\u00a0Andaman and Nicobar islands<\/span>.<\/p>\n

\"Mangrove
Source- Researchgate<\/figcaption><\/figure>\n

<\/a>What is the significance of Corals?<\/strong><\/span><\/h2>\n

1. Rainforests of the sea-<\/strong>\u00a0Coral reefs\u00a0support over 25% of marine biodiversity<\/span>, including fish, turtles and lobsters, while taking up 1% of the seafloor.\u00a0For ex-<\/strong>\u00a0The Great Barrier Reef\u00a0<\/span>contains over\u00a0400 coral species<\/span>,\u00a01,500 fish species<\/span>,\u00a04,000 mollusc species\u00a0<\/span>and\u00a0six of the world\u2019s seven sea turtle species<\/span>.<\/p>\n

2. Economic value-<\/strong>\u00a0Coral structures provide\u00a0economic goods and services worth about $375 billion each year<\/span>. More than\u00a0500 million people<\/span>\u00a0across the world dependent on coral reefs for food and income.<\/p>\n

3. Coastal protection-<\/strong>\u00a0Coral reefs absorb up to\u00a097% of the energy from waves, storms, and floods<\/span>, which prevents loss of life, property damage, and soil erosion. The absence of coral reefs results in severe ramifications for marine life and humans.<\/p>\n

<\/a>What is coral bleaching? What are the mass coral bleaching events which have taken place?<\/strong><\/span><\/h2>\n

Coral Bleaching-<\/strong>\u00a0When\u00a0corals are stressed<\/span>\u00a0by\u00a0changes in conditions<\/span>\u00a0such as\u00a0temperature<\/span>,\u00a0light<\/span>, or\u00a0nutrients<\/span>, they expel the symbiotic algae (zooxanthellae<\/span>) living in their tissues, causing them to turn completely white. This is called\u00a0coral bleaching<\/span>.<\/p>\n

Coral Death-<\/strong>\u00a0Bleached corals can survive depending on the levels of bleaching and the recovery of sea temperatures\u00a0to normal levels<\/span>. If heat-pollutions subside in time, over a few weeks, the zooxanthellae can come back to the corals and restart the partnership. But in\u00a0cases of severe bleaching and prolonged stress\u00a0in the external environment<\/span> can lead to\u00a0coral death<\/span>.<\/p>\n

Mass Coral Bleaching Events<\/strong><\/p>\n\n\n\n\n\n
First Mass Bleaching<\/strong><\/td>\nIt occurred in\u00a01998<\/span>\u00a0when the El Ni\u00f1o weather pattern caused sea surfaces in the\u00a0Pacific Ocean to heat up<\/span>. This event led to the\u00a0death of 8% of the world\u2019s coral<\/span>.<\/td>\n<\/tr>\n
Second Mass Bleaching<\/strong><\/td>\nThis event took place in\u00a02010<\/span>. It led to\u00a0increased destruction of\u00a035% coral reefs<\/span>.<\/td>\n<\/tr>\n
Third Mass Bleaching<\/strong><\/td>\nThe event that took place between\u00a02014-17<\/span>\u00a0and affected reefs in Guam in the\u00a0Western Pacific region<\/span>,\u00a0the North<\/span>,\u00a0South-Pacific<\/span>, and\u00a0the Indian Ocean<\/span>. It affected 56% of coral reefs around the world.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Fourth global bleaching event is currently underway. Nearly 54 countries, territories and local economies- from Florida, the US, Saudi Arabia to Fiji- have confirmed bleaching. Bleaching has been confirmed in the Western Indian Ocean<\/span>, including Tanzania<\/span>, Kenya<\/span>, Mauritius<\/span>, Seychelles<\/span>, and off the western coast of Indonesia<\/span>.<\/p>\n

<\/a>What are the Causes Responsible for Coral Bleaching?<\/strong><\/span><\/h2>\n

1. Rise in Sea Temperature-<\/strong>\u00a0The rise in global warming has led to increase in the sea temperatures which has resulted in the destruction of corals.<\/p>\n

2. Ocean Acidification-<\/strong>\u00a0Due to rise in carbon dioxide levels, oceans absorb more carbon dioxide. This\u00a0increases the acidity of ocean water<\/span>\u00a0and\u00a0inhibits the coral\u2019s ability to create calcareous skeletons<\/span>, which is essential for their survival.<\/p>\n

3. Solar radiation and ultraviolet radiation-<\/strong>\u00a0Changes in tropical weather patterns\u00a0<\/span>result in less cloud cover and more radiations which induce coral bleaching.<\/p>\n

4. Infectious Diseases-<\/strong>\u00a0Penetration of bacterium like\u00a0vibrio shiloi\u00a0<\/span>inhibits\u00a0photosynthesis of zooxanthellae<\/span>. These bacteria become more potent with elevated sea temperatures.<\/p>\n

5. Chemical Pollution-<\/strong>\u00a0Increased nutrient concentrations affect corals by promoting phytoplankton growth<\/span>, which in turn supports increased numbers of organisms that compete with coral for space.<\/p>\n

6. Human Induced Threats-<\/strong>\u00a0Over-fishing<\/span>,\u00a0pollution from agricultural and industrial runoff<\/span>,\u00a0coral mining<\/span>,\u00a0development of industrial areas<\/span> near coral ecosystems\u00a0also adversely impact corals.<\/p>\n

<\/a>What are the consequences of coral bleaching?<\/strong><\/span><\/h2>\n

1. Affecting the Food Chain-<\/strong>\u00a0Changes in coral communities can\u00a0affect the species that depend on them<\/span>, such as the fish and invertebrates<\/span>\u00a0that rely on live coral for food, shelter. Loss of such marine animals can disturb the entire food chain.<\/p>\n

2. Loss of Biodiversity-<\/strong>\u00a0Declines in genetic and species diversity occurs when corals die as a result of bleaching.<\/p>\n

3. Economic Decline-<\/strong>\u00a0Bleached and degraded reefs can discourage tourism, which can affect the local economy.<\/p>\n

4. Affects Food Availability-<\/strong>\u00a0Coral bleaching can cause\u00a0large shifts in fish communities<\/span>.\u00a0This can translate into reduced catches for fishers, which in turn impacts food supply and associated economic activities.<\/p>\n

5. Impact on Coastal Protection-<\/strong>\u00a0Coral reefs protect coastlines by absorbing constant wave energy from the ocean, thereby protecting people living near the coast from increased\u00a0storm damage<\/span>, erosion<\/span> and flooding<\/span>.<\/p>\n

<\/a>What are the Initiatives to Protect Corals?<\/strong><\/span><\/h2>\n

A number of global initiatives are being taken to address the issues-<\/p>\n\n\n\n\n\n\n
Institution of International organisations<\/strong><\/td>\n\u00a0International Coral Reef Initiative, Global Coral Reef Monitoring Network (GCRMN), Global Coral Reef Alliance (GCRA) and The Global Coral Reef R&D Accelerator Platform have been established to deal with the issue.<\/td>\n<\/tr>\n
Biological restoration<\/strong><\/td>\nIt uses methods for coral growth and transplanting to assist the restoration of a coral reef. It includes\u00a0Asexual propagation<\/span> and Coral Gardening<\/span>.<\/td>\n<\/tr>\n
Structural restoration<\/strong><\/td>\nIt involves the construction of artificial reefs<\/span>, or relocation of rocks\/dead coral heads<\/span>. The goal is to increase the amount of reef structure<\/span> and habitat available for the corals and other reef organisms to grow on<\/span>. For ex-<\/strong> Bio rock technology<\/span><\/td>\n<\/tr>\n
Physical restoration<\/strong><\/td>\nIt addresses the conditions in which the corals are growing to improve their\u00a0health, growth rates, or reproductive ability.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

<\/a>What should be the way forward?<\/strong><\/span><\/h2>\n

1. Halting unplanned development-<\/strong>\u00a0Halting unplanned coastal development would play a significant role in reversing the decline of reefs in some locations.<\/p>\n

2. Promotion of sustainable fishing-<\/strong>\u00a0Promoting sustainable fishing and providing opportunities for ecotourism<\/span> can help conserve corals.<\/p>\n

3. Minimal use of chemical fertilisers-<\/strong>\u00a0There is a need to\u00a0minimise the use of chemically enhanced fertilizers, insecticides, pesticides, and herbicides\u00a0which are non degradable<\/span> and harm corals.<\/p>\n

4. Measures for prevention of global warming-<\/strong>\u00a0Taking all possible measures to prevent actions that worsen global warming<\/span> since Climate change is the greatest global threat to coral reef ecosystems.<\/p>\n\n\n\n
Read More- Livemint<\/a>
\nUPSC Syllabus- GS 3- Environment conservation, GS 1- Effects of Climate Change<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"excerpt":{"rendered":"

Researchers at the ICAR-Central Marine Fisheries Research Institute have found that marine heatwaves since October 2023 have resulted in widespread bleaching of coral reefs in the Lakshadweep Sea. Further, according to the US National Oceanic and Atmospheric Administration (NOAA), the fourth global mass coral bleaching event has been triggered by extraordinary ocean temperatures. The mass… Continue reading Coral Bleaching- Explained Pointwise<\/span><\/a><\/p>\n","protected":false},"author":10357,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"footnotes":""},"categories":[130,1],"tags":[],"class_list":["post-295143","post","type-post","status-publish","format-standard","hentry","category-7-pm","category-uncategorized","entry"],"jetpack_featured_media_url":"","views":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts\/295143","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/users\/10357"}],"replies":[{"embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/comments?post=295143"}],"version-history":[{"count":0,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts\/295143\/revisions"}],"wp:attachment":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/media?parent=295143"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/categories?post=295143"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/tags?post=295143"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}