tailieunhanh - IELTS Academic Reading 19

Với IELTS Academic Reading 19 sẽ giúp các bạn ôn tập củng cố lại kiến thức và kỹ năng giải bài tập để chuẩn bị cho kỳ thi sắp tới đạt được kết quá mong muốn. Mời các bạn tham khảo. | IELTS Academic Reading 19 You should spend about 20 minutes on Questions 1-13 which are based on Reading Passage 19 below. Creating Artificial Reefs In the coastal waters of the US a nation s leftovers have been discarded. Derelict ships concrete blocks scrapped cars army tanks tyres filled with concrete and redundant planes litter the sea floor. However this is not waste disposal but part of a coordinated state-run programme. To recently arrived fish plants and other sea organisms these artificial reefs are an ideal home offering food and shelter. Sea-dumping incites widespread condemnation. Little surprise when oceans are seen as convenient dumping grounds for the rubbish we have created but would rather forget. However scientific evidence suggests that if we dump the right things sea life can actually be enhanced. And more recently purpose-built structures of steel or concrete have been employed - some the size of small apartment blocks -principally to increase fish harvests. Strong currents for example the choice of design and materials for an artificial reef depends on where it is going to be placed. In areas of a solid concrete structure will be more appropriate than ballasted tyres. It also depends on what species are to be attracted. It is pointless creating high-rise structures for fish that prefer flat or low-relief habitat. But the most important consideration is the purpose of the reef. In the US where there is a national reef plan using cleaned up rigs and tanks artificial reefs have mainly been used to attract fish for recreational fishing or sport-diving. But there are many other ways in which they can be used to manage the marine habitat. For as well as protecting existing habitat providing purpose-built accommodation for commercial species such as lobsters and octupi and acting as sea defences they can be an effective way of improving fish harvests. Japan for example has created vast areas of artificial habitat - rather than isolated reefs - to .