Fuente: News » Research
  Expuesto el: lunes, 23 de julio de 2012 11:51
  Autor: Janis Morgan
  Asunto: Adding iron to the sea could combat climate change
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 Scientists at the    University of Liverpool have found that adding iron to the sea could    alleviate the impact of climate change. The team showed that much    of the algae which grows when iron is added to the sea dies and falls into    the deep ocean, taking with it the carbon it has absorbed. They added several    tonnes of iron sulphate to a 1,67sq km patch within an ocean eddy near    Antarctica which, within a week, had caused a large algae growth in the    iron-limited but nutrient-rich ocean region. Although algae, which consists    of microscopic marine plants and photosynthetic microbes, grows naturally in    the ocean. there is only limited iron in sea water in this region so adding    iron makes it possible to grow algae. Over a seven-week period,    scientists monitored the water inside and outside the eddy before, during and    after the deployment of iron. They found that after three weeks, the    phytoplankton, which was initially within the top 100 metres of the ocean,    sank below 1,000 metres, taking with it the carbon it had absorbed from the    atmosphere and sending it to the ocean floor, where scientists believe it    will remain in a `fluff layer` for many centuries or longer. Dr Harry Leach, from the    School of Environmental Sciences, who was part of the international team    working on the research, said: “The study took place in a self-enclosed eddy    which acted as a giant test tube so we could compare what happened within it    with control points outside. “Using a range of    instruments to monitor nutrient and plankton levels from the ocean’s surface    to the bottom, we were able to conclude that at least half of the algae had    fallen below 1,000m and a substantial portion was likely to have reached the    sea floor taking over half of the carbon absorbed from the surface. “We have demonstrated for    the first time that carbon, absorbed by algae in an iron-fertilised bloom,    can sink to the ocean bed. This contributes to our understanding of the    global carbon cycle and has implications for potential ways of mitigating    rising levels of carbon dioxide – one of the major causes of climate change. “However, more    experiments are needed to decide if these results provide a viable solution    to reducing atmospheric carbon dioxide.” The European Iron Fertilization    Experiment (EIFEX) was carried out using the German Polarstern research ship    and the research was led by the Alfred Wegener Institute for Polar and Marine    Research in Bremerhaven. Leave a commentYou must be logged    in to post a comment. Articles by category
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