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Save Our Seeds
Over the past four hundred years, four hundred and fifty types of plants and trees around the world have become extinct as a result of the combined effects of global warming, population growth, deforestation, flooding and the fact that deserts are advancing in some regions at a rate of nearly four miles a year. Scientists estimate a quarter of the world's remaining 270, 000 plant species will be under threat of extinction by 2050. In 1997, in an attempt to try to prevent the loss of such precious resources, volunteers all over Britain began collecting seeds from Britain's 1, 400 species of wild plants, three hundred of which are already facing extinction. The seeds collected are now housed in the Millennium Seed Bank, which opened its doors in 2000. Run by the Royal Botanical Gardens department of the famous Kew Gardens in London, the bank is located in Sussex, about thirty-five miles outside of the capital. The bank is expected to become the world's biggest seed bank and, apart from preserving almost all the plant life in Britain, it also aims to have saved the seeds of more than 24, 000 species of plant life, almost a tenth of the world's flowering plants, in the next twenty years. If they are successful, the Millennium Seed Bank Project will be one of the largest international conservation projects ever undertaken. In order to achieve this aim, the Millennium Seed Bank has a team of scientists who travel to remote corners of the world to find and collect seeds. They work together with local botanists and also help them to set up their own seed banks by training local scientists. They also spend a great deal of time negotiating with governments to allow them to collect the seeds and bring them back to Britain for storage in the Millennium Seed Bank. When these seeds arrive at the seed bank, they are sorted, separated by hand from their pods, cleaned and dried and then X-rayed to make sure that they haven't been damaged in any way that might stop them from growing into healthy plants. Finally, they are placed in ordinary glass jars and stored in three underground vaults at temperatures of -20°C. Most plant species have seeds that can be dried, frozen and stored for years and still grow into healthy plants. However, the seeds of some species cannot be dried, so they can't be stored in seed banks in the usual way. These seeds include many rainforest tree species and plants that grow underwater. Roger Smith, head of the Millennium Seed Bank, explains that scientists at the bank are already working on finding new ways of storing those seeds that cannot survive the drying and freezing process, and also on how to regenerate the seeds when they become extinct in their natural habitats. " At the moment, all we're doing is preserving these plants for the future. We won't have managed to conserve any species until we find the way to successfully regenerate them and grow new plants from them, " points out Smith. " But at least this way, when the technology becomes available, and it will, we won't have lost everything." As well as preserving seeds for the future, the seed bank also receives 2000 requests per year for seeds from universities, governments and conservationist organisations for use in various types of research - for example, to find cures for diseases, to grow food in the developing world and to help in projects that restore the natural habitats of endangered animal species so they can be released back into the wild. Dr Hugh Pritchard, head of research at the Millennium Seed Bank, says: " While it's true that many of the plants we preserve at the bank aren't useful at the moment, that doesn't mean they won't become useful in the future. Something like thirty per cent of the medicines we use today are based on products or chemicals which have been extracted from plants. So it's easy to see why we need to preserve the diversity of the earth's plant life for the future."
1 What do scientists believe will happen by 2050? A All plant life will be altered. B 450 types of plants will be in danger of becoming extinct. C Part of the world's plant life will face extinction D Environmental factors will affect only 450 plant species. 2 Where can the Millennium Seed Bank be found? A outside Sussex B outside London C in the Royal Botanical Gardens D in the Kew Gardens 3 The main objective of the Millennium Seed Bank is to A save the seeds of thousands of the world's plants. B protect all flowering plants in the world. C start a new international project in the next few years. D undertake a larger conservation project soon. 4 The Millennium Seed Bank carries out its work by A training foreign governments to plant seeds. B travelling around the world with botanists from other countries. C helping other international seed banks. D collecting international seeds and returning them to Britain for storage. 5 The methods used in storing the seeds show that A all seeds can be preserved for many years. B some species cannot be stored by regular means. C some of the plant species develop into healthy plants. D some seeds are damaged when X-rayed. 6 The Millennium Seed Bank is trying to A reproduce new plants from the seeds. B reduce the storage lives of some seeds. C destroy the seeds that cannot be frozen. D plant the seeds that have a short storage life. 7 Why is this project important, according to Dr Pritchard? A It's useful to medical research. B It's useful in technological research. C It helps governments in developing countries. D It helps animal habitats.
Завідувач кафедри __________ Т.І. Крехно Викладачi _______________І.С. Лученцова _______________ А.О. Пікалова _____________ C.О. Тимошенко
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