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Deep sea threats

  2. SOURCES OF DEEP OCEAN THREATS:  Fishing:  Overfishing.  Factory fishing.  Pirate fishing.  Pollution.  Mining and drilling.  Whaling and by catch.  Global warming.
  3. WRONG FISHING ACTIVITIES:  Overfishing:  Depletes the stock of fish beyond their ability to recover  Disrupting the ecosystem.  Factory fishing:  Giant ships use state of the art equipment to locate and vacuum entire schools of fishes  Pirate fishing:  Armed and masked ships, scouring the oceans and steal the food of the hungry families.
  5. MINING AND DRILLING ACTIVITIES:  Valuable reserves also located under the deep ocean floor  Explore down to 3,000m  Such activity could have devastating effects on fragile, slow growing deep- sea communities.  Deep water horizon
  6. WHALING AND BYCATCH:  Whales play an important role in nutrient cycling.  Japan slaughtering events in Taiji.  Bottom trawls and fishing nets actions to whales and dolphins.
  7. GLOBAL WARMING:  Basically population compositions changed in response to changing environmental conditions. When deep cold water warms, species normally restricted to shallower or warmer waters can extend their ranges downward. These animals could either have been going up or down in depth or shifting laterally, trying to find their preferred temperature and environment.
  8. THANK YOU !!

Notas del editor

  1. We talk about sources of deep sea threats and their impacts and their action to the ecosystem
  2. Illustrating the diff between different fishing behaviors And talk about green peace actions
  3. Bottom trawling is currently the greatest threat to deep-sea biodiversity. First introduced in the 1980s, rockhopper trawls fitted with large rubber tires or rollers allow bottom trawling on virtually all of the ocean floor down to a depth of 2,000m.These trawls - whose use is now widespread - crush everything in their path. In an experiment off Alaska, 55% of cold-water coral damaged by one pass of a trawl had not recovered a year later. Scars up to 4km long have been found in the reefs of the north-east Atlantic Ocean. And in heavily fished areas around coral seamounts off southern Australia, 90% of the surfaces where coral used to grow are now bare rock.  Deep-sea species are generally extremely slow growing and do not reach sexual maturity for many years. Some commercial deep-sea fish also congregate in large numbers around seamounts to feed and spawn. And many deep-sea fisheries are located on the High Seas where there is often little or no regulation. These factors make deep-sea fish extremely vulnerable to overfishing. Newly fished populations of deep-sea species like Patagonian toothfish and orange roughy, for example, have been fished to commercial extinction in just a few years. At present most deep-water species are likely to be over-exploited - and as many as 40% of the world’s fishing grounds are now in waters deeper than 200m.
  4. Ocean used as dumping site where trashes buried in pacific and by current action it will move or even decay and then bioaccumlate in our food chain
  5. Nuclear wastes consider a big threat where it may leak and cause destructive damages to man and animals As what happened in fukoshema where leakage biomagnify inside humans and cause many threats within.
  6. Oil, gas, and mineral exploration: At present, most oceanic reserves of oil, gas, and minerals are extracted from the continental shelf, under shallow coastal waters. However, with valuable reserves also located under the deep ocean floor, the oil and mining industries are expected to venture further afield, and eventually explore down to 3,000m. Such activity could have devastating effects on fragile, slow growing deep-sea communities.
  7. Ocean mining in the deep sea is yet another source of ocean pollution. Ocean mining sites drilling for silver, gold, copper, cobalt and zinc create sulfide deposits up to three and a half thousand meters down in to the ocean. While we have yet the gathering of scientific evidence to fully explain the harsh environmental impacts of deep sea mining, we do have a general idea that deep sea mining causes damage to the lowest levels of the ocean and increase the toxicity of the region. This permanent damage dealt also causes leaking, corrosion and oil spills that only drastically further hinder the ecosystem of the region.
  8. Whales have an important role to play in nutrient cycling. Their poo, for example, makes organic carbon more accessible to smaller organisms. Even a dead whale carcass is important in carbon cycling, particularly the export of carbon to the deep sea. The falling carcass (whale fall) brings carbon acquired at the surface (usually in the form of plankton) to the sea floor as the whale's body (a large carbon reservoir) sinks. The larger the whale, the more carbon-filled tissues it has, meaning that larger whales export more carbon. Whaling has reduced the size of whale populations and the size of whales. It has been estimated that bringing whale populations back to their natural level will mean 1.6 x 105 tonnes of carbon could be exported to the deep sea through whale falls - that works out at over 36 double decker busses worth of carbon per day! This is important in the context of global climate change as this export of carbon to the sediment means it can no longer interact with the atmosphere. As it falls to the sea floor, a whale carcass can provide food for hundreds of organisms as they flock to a food source that can keep them going in an environment usually devoid of such bountiful food resources. Here, scavengers such as hagfish sleeper sharks and many invertebrates chomp their way at the whale's soft tissue, removing 40-60 kg of it per day. Deep sea worms and crustaceans also feast on the whale carcass, until only the bones remain - the feasting is not over yet though, as this fuels a host of bone-munching microbes that break down the remains of the whale.
  9. This is a scanning electron microscope image of the shell of a deep-sea Ostracoda (Crustacea). The excellent fossil record of microscopic ostracod fossils in the deep ocean was used to estimate past biodiversity changes in a recent study by scientists based in Hong Kong, the United States and Norway. They determined that even ecosystems in the deepest ocean will feel the impact of climate change. (Image courtesy of Moriaki Yasuhara, The University of Hong Kong) Even tiny crustaceans scuttling across the deepest, darkest depths of the ocean floor will feel the effects of climate change, according to a new study published in the journal Global Ecology and Biogeography. “The deep sea is so remote and so very, very cold that we wondered if it too will be impacted by climate change,