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El polvorín

Censo de Vida Marina: 6,000 nuevas especies en los océanos del mundo

5 Octubre 2010 , Escrito por El polvorín Etiquetado en #Politica

Global marine life census charts vast world beneath the seas

No obstante, hay “un declive generalizado de la abundancia marina”, siendo una excepción la recuperación de especies. El censo es indicativo de que los océanos “están más alterados de lo que se esperaba” como consecuencia de la contaminación causada por la actividad humana.

En 10 años de trabajo, más de 250,000 especies fueron catastradas por 2.700 científicos de 80 países.

"Este programa no tiene parangón en la historia de la humanidad". Así de claro es Víctor Gallardo, oceanógrafo de la Universidad de Concepción, para referirse al Censo de la Vida Marina, una investigación de la que formó parte, junto a otros 2.700 científicos de 80 países, para estudiar la biodiversidad de los océanos y mares del mundo y que ayer reveló su informe final en Londres, tras una década de estudios.

¿Sus resultados? Se catastraron 250 mil especies, en 25 zonas del planeta, y se descubrieron 6 mil, de las cuales 1.200 ya fueron descritas formalmente. "Esto representa el primer esfuerzo por documentar lo que vive en los océanos, lo que vivió y lo que vivirá", dice a La Tercera Patricia Miloslavich, bióloga marina e integrante de la comisión central del Censo de Vida Marina.

Durante los 10 años de investigación, los científicos lograron determinar las zonas con mayor biodiversidad marina del planeta -25 en total-, entre las que destacan las costas de Corea, China, Australia y Nueva Zelandia. No sólo eso: además de cuantificarlas y analizarlas, lograron definir qué especies dominan los océanos del mundo: un 19% son crustáceos, 17% moluscos, 12% peces, 10% protozoos y un 10% algas.

Otro gran hito es que logró centralizar, por primera vez, toda la información disponible sobre biodiversidad marina en un solo sitio web de libre acceso (Obis). Gracias a esto, científicos de todo el mundo podrán acceder a datos como la base genética de más de 35 mil especies marinas. "Es un caso único de coordinación, organización, cooperación y persistencia, que esperamos no sea el último, porque aún queda mucho por conocer en esta área", dice Gallardo a La Tercera. De hecho, se estima que quedan 750.000 nuevas especies por descubrir, pues más del 20% del volumen total de los océanos no ha sido explorado ni catastrado.

Los hallazgos en Chile

El Censo dividió los océanos en 25 zonas. Chile está en la región de la corriente de Humboldt. De las 10.201 especies catastradas de esta zona, hay 15 nuevas que están en los mares de Chile. De hecho, una de ellas, el cangrejo yeti (Kiwa hirsuta), ha sido una de las imágenes ícono del Censo. Fue descubierto en 2006, al sur de Isla de Pascua, por una expedición norteamericana, y sus blancas y peludas tenazas son ocupadas como ejemplo de biodiversidad.

cangrejo yeti (Kiwa hirsuta)

Otro hallazgo destacado son las bacterias gigantes descubiertas por Gallardo y su equipo en la costa centro- sur del país y que ocupan la superficie del tamaño de Grecia. Este descubrimiento también corroboró que en peso, la vida marina es principalmente microbiana y superior a la terrestre. Por ejemplo, el peso de los microbios marinos es equivalente a 35 elefantes para cada persona que vive en la Tierra. También están el descubrimiento de los corales de mares fríos en la zona austral, la frecuencia de ballenas azules en la misma región -que ha dado pauta para declarar su protección- y diversos tipos de crustáceos en el norte del país.

Javier Sellanes, biólogo marino de la U. Católica del Norte -uno de los investigadores que más especies nuevas ha catalogado en nuestro país-, revela también cómo esta investigación permitió conocer las principales amenazas que existen para nuestra biodiversidad: la falta de oxígeno en el agua, por faenas productivas, y la sobrepesca que muchas veces arrasa con ecosistemas enteros.

"El efecto de las redes de arrastre sobre las comunidades bentónicas (que viven en el fondo marino) equivale a talar un bosque", dice Sellanes.

 
 
Redes de arrastre de fondo destruyen preciosas formas de vida como estos corales con cientos de años de vida        A photograph taken by an onboard observer shows a very large piece of red gorgonian coral, hundreds of years old, being manhandled to dump it back into the ocean. Other pieces of coral are on the deck of the vessel in bottom trawling nets.
 

Tras diez años de investigaciones y el trabajo de más de 2.700 científicos de todo el mundo, el Censo de la Vida Marina (CVM) reveló hoy una máquina para descubrir belleza que ha catalogado toda la vida que habita y ha existido en los océanos. Seguir leyendo el arículo

Foto y Vídeo relacionado

La labor de estos científicos ha permitido descubrir 6.000 nuevas especies marinas, desde seres microscópicos hasta calamares pasando por corales, y ahora se estima que el número de especies que habita los océanos es cerca de 250.000, 20.000 más que lo calculado antes del inicio de los trabajos.

En la última década, los científicos han realizado 540 expediciones por todos los mares del planeta y han pasado más de 9.000 días recogiendo especímenes, realizando inmersiones en las aguas más profundas del planeta, enviando robots a los ambientes más inhóspitos.

Aún así, CVM sigue sin tener ningún tipo de registro de más del 20 por ciento del volumen de los océanos y sólo unos pocos de vastas regiones marinas

La biodiversidad del Mediterráneo, la más amenazada del mundo ...

2 Ago 2010 ... Los científicos del Censo de Vida Marina publican en la revista PLoS One un inventario de la biodiversidad y distribuciones de especies ...www.plataformasinc.es/.../La-biodiversidad-del-Mediterraneo-la-mas-amenazada-del-mundo -

 

Global marine life census charts vast world beneath the seas

Global marine life census charts vast world beneath the seas 
a recently discovered species called a squidworm found in the Celebes …

LONDON (AFP) – Results of the first ever global marine life census were unveiled Monday, revealing a startling overview after a decade-long trawl through the murky depths.

The Census of Marine Life estimated there are more than one million species in the oceans, with at least three-quarters of them yet to be discovered.

The 650-million-dollar (470-million-euro) international study discovered more than 6,000 potentially new species, and found some species considered rare were actually common.

The study said it offered "an unprecedented picture of the diversity, distribution and abundance of all kinds of marine life in Planet Ocean -- from microbes to whales, from the icy poles to the warm tropics, from the tidal near shores to the deepest dark depths."

The census establishes a baseline against which 21st-century changes can be monitored.

New species were discovered, marine highways and rest stops mapped and changes in species abundance were documented.

The research involved more than 2,700 scientists, 670 institutions, more than 540 expeditions and around 9,000 days at sea. Nearly 30 million observations of 120,000 species were made.

The census was formally launched in London, with more than 300 figures involved gathering to share the results and consider their implications.

"The census has far exceeded any dream that I had. We felt like the people who created the first dictionary and encylopedia 250 years ago," said Jesse Ausubel, a scientist who co-founded the study.

"The most surprising thing was beauty. Our eyes pumped out of our head in front of this beauty."

The survey set out to find out what used to live in the oceans, what lives there now and what might live there in the future.

The census said 16,764 species of fish had so far been described, but an estimated 5,000 more were yet to be discovered.

Scientists found some species thought extinct 50 million years ago, while other finds were less encouraging.

Around 40 percent of plankton, at the bottom of the ocean food chain, has disappeared in the last 30 years, which was put down to a rise in ocean temperatures.

Sharks have disappeared from 99 percent of some areas.

Australian Ian Poiner, chair of the census steering committee, said the researchers "systematically defined for the first time both the known and the vast unknown, unexplored ocean".

"All surface life depends on life inside and beneath the oceans. Sea life provides half of our oxygen and a lot of our food and regulates climate. We are all citizens of the sea," he said.

"While much remains unknown, including at least 750,000 undiscovered species and their roles, we are better acquainted now with our fellow travellers and their vast habitat on this globe."

The census documented a changing marine world, richer in diversity, more connected through distribution and movements, more impacted by humans and less explored than was expected.

The researchers used sound, satellites and electronics to track migratory routes.

They got down to 10 kilometres (6.2 miles) below the sea in the western Pacific Ocean's Mariana Trench.

They affirmed that by weight up to 90 percent of marine life is microbial -- with the equivalent of 35 elephants for every living person.

Scientific steering committee vice-chair Myriam Sibuet of France, said: "The census enlarged the known world. Life astonished us everywhere we looked.

"In the deep sea we found luxuriant communities despite extreme conditions. The discoveries of new species and habitats both advanced science and inspired artists with their extraordinary beauty."

Much of the marine world remains to be explored, so vast are the seas.

The census shows where explorers have not yet looked. For more than 20 percent of the oceans' volume, the database has no records at all, and for large areas very few.

The findings are partially available on the www.iobis.org website.

  • A polychaete worm (vigtorniella sp) found at a whale fall at Sagami Bay, Japan is seen in this undated handout. Scientists completed a 10-year census of marine life on October 4, after finding thousands of exotic new species in a project that will help assess threats to the oceans ranging from climate change to BP's oil spill.  REUTERS/Yoshihiro Fujiwara/JAMSTEC/Handout

     

    Census of marine life shows how various underwater life forms are connected to one another

    Census of marine life took place over a ten-year period and cost $650 million. Over 200 thousand life forms were identified in the census of marine life.

    By Seth Borenstein, Associated Press / October 4, 2010

    The world's oceans may be vast and deep, but a decade-long count of marine animals finds sea life so interconnected that it seems to shrink the watery world.

    An international effort to create a Census of Marine Life was completed Monday with maps and three books, increasing the number of counted and validated species to 201,206.

    A decade ago the question of how many species are out there couldn't be answered. It also could have led to a lot of arguments among scientists. Some species were counted several or even dozens of times, said Jesse Ausubel of the Alfred Sloan Foundation, the co-founder of the effort that involved 2,700 scientists.

    The $650 million project got money and help from more than 600 groups, including various governments, private foundations, corporations, non-profits, universities, and even five high schools. The Sloan foundation is the founding sponsor, contributing $75 million.

    But what scientists learned was more than a number or a count. It was a sense of how closely life connects from one place to another and one species to another, Ausubel said.

    Take the bizarre and minuscule shrimp-like creature called Ceratonotus steiningeri. It has several spikes and claws and looks intimidating — if it weren't a mere two-hundredths of an inch long. Five years ago this critter had never been seen before. No one knew of its existence.

    Then, off the Atlantic coast of Africa as part of the census, it was found at a depth of more than three miles below the surface. It was one of 800 species found in that research trip, said discoverer Pedro Martinez Arbizu, a department head at the German Centre for Marine Biodiversity Research.

    He was astonished to find that the tiny creature also was within the cataloging he'd made earlier 8,000 miles away in the central Pacific.

    There was that critter again. Same shrimpy creature, different ocean.

    "We were really very, very surprised about that," Arbizu said in an interview. "We think this species has a very broad distribution area."

    In that way, Ceratonotus steiningeri exemplifies what the census found.

    "We didn't know so much about the deep sea...," Arbizu said. "We believe now that the deep sea is more connected, also the different oceans, than we previously thought."

    The census also describes a species of strange large squid that was only recently found in waters more than 3,000 feet deep. The 23-foot-long squid has large fins with arms and tentacles that have elbow-like bends. Scientists had seen it in larvae form before, but not in its full-blown glory until it was filmed at depth.

    The census also highlighted marine life that makes commutes that put a suburban worker's daily grind to shame. Before the census started, the migration of the Pacific bluefin tuna had not been monitored much. But by tagging a 33-pound tuna, scientists found that it crossed the Pacific three times in just 600 days, according to Stanford University's Barbara Block. A different species of tuna, the Atlantic bluefin, migrates about 3,700 miles between North America and Europe. Humpback whales do a nearly 5,000 mile north-south migration.

    Still, that's nothing compared to the sea bird that Ian Poiner of Australia studies.

    He studied puffins that make a nearly 40,000-mile circle every year from New Zealand to Japan, Russia, Alaska, Chile and back in what the census calls the "longest-ever electronically recorded migration."

    Other species, such as plankton and even seals, travel great lengths, but stay in the same part of the ocean. They travel thousands of feet between the surface into the depths of the oceans. The scientists measured elephant seals that dived about 1.5 miles, Ausubel said.

    The census found another more basic connection in the genetic blueprint of life. Just as chimps and humans share more than 95 percent of their DNA, the species of the oceans have most of their DNA in common, too. Among fish in general, the snippets of genetic code that scientists have analyzed suggest only about a 2 to 15 percent difference, said Dirk Steinke, lead scientist for marine barcoding at the University of Guelph in Canada.

    "Although these are really old species of fish, there's not much that separates them," Steinke said.

    Marine Life Census Yields Thousands of New Species

    Marine Life Census efforts have taken 10 years, but 2,700 scientists from 80 countries have completed the census work and have revealed thousands of new species, its U.S. founders say. The initiative launched 570 expeditions that produced more than 2,600 academic papers and collected 30 million observations of 120,000 species. Researchers found a possible 6,000 new species, 1,200 of which have ... http://www.thirdage.com/news/marine-life-census-yields-thousands-new-species_10-4-2010

     

     

     

     

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