Coastal pollution

Vocabulary

fishery – рыболовный промысел

inland fishery - рыболовство во внутренних водоемах

vessel – судно, корабль

fish stocks – рыбные ресурсы, рыбные запасы

species of fish – виды рыб

rebuild depleted stocks – восстановить истощенные запасы

over-exploited – чрезмерно использованный

capture fisheries – рыболовный промысел, рыболовство

squid – кальмар, приманка для ловли рыбы

shrimp - креветка

bottom dwelling fish – придонная рыба

halibut – палтус, камбаловые

sole – морской язык

flounder – речная камбала

protein intake – потребление белка

food supply – кормовая база, пищевые ресурсы

Read the text and answer the following questions:

1. Talk about the state of fisheries.

2. What is the state of fisheries in the Black sea?

3. What are the main reasons of collapse of fisheries?

4. What are the consequences of collapsing fisheries?

5. Can aquaculture substitute for the declining ocean fish catch?

6. What countries are the top fish producers?

Rapidly expanding populations and the growth of cities along coastlines has contributed to a rising tide of pollution in nearly all of the world's seas. Between 80 per cent and 90 per cent of all commercial fish are caught within 320 kilometres of land, and many within 50 kilometres. Thus pollution, mostly from land-based sources, is a contributing factor in falling catches.

Coastal urban areas dump increasing loads of toxic wastes into the sea. In fact, waters around many coastal cities have turned into virtual cesspools, so thick with pollution that virtually no marine life can survive. Let us consider the following:

· Despite over two decades of cleanup efforts, the Mediterranean Sea is on the receiving end of between 30 and 50 million metric tons of untreated or partially treated sewage every year;

· The Lagoon of Iddo in Lagos, Nigeria, gets 60 million litres of raw sewage a year, along with vast quantities of industrial waste;

· Calcutta and Bombay, India, respectively, dump 400 million metric tons and 365 million metric tons of raw sewage and other municipal wastes into coastal waters every year;

· Karachi, Pakistan's largest city, empties 175 million metric tons of untreated sewage and industrial filth into the Arabian Sea every year;

· Chinese cities and towns along the Yellow Sea discharge 50-60 million metric tons of untreated or partially treated municipal wastes every day into coastal waters;

· The Bays of Valparaiso and Concepcion, Chile receive a combined total of 244 million metric tons of untreated effluents a year, mostly from copper mines, pulp and paper mills, fish processing plants and oil refineries;

· In 2007, researchers identified over 200 'dead zones' around the world's coastlines, an increase of 51 such zones since 2003, when scientists reported 149 such biological dead zones in the world's seas. Dead zones are areas where the dissolved oxygen levels are so low that no marine life can be sustained (other than micro-organisms). Moreover, these biologically dead areas are expanding due mainly to high nutrient pollution levels brought in by rivers and streams and washed off coastal land. Since the 1960s, the number of dead zones has doubled every decade. The dead zone in the Gulf of Mexico, now the world's second largest, covers 21,000 square kilometres, an area the size of New Jersey. The world's largest dead zone is in the Baltic Sea, covering some 70,000 square kilometers of seabed.

Ocean currents transport pollutants into the remotest corners of the world's seas. No place in the world ocean is immune from the depredations of humanity. Toxic chemicals, such as PCBs and DDT, for instance, have turned up in the fatty tissues and blubber of seals in the Arctic and penguins in the Antarctic, thousands of kilometers from population centers. Beluga whales found in the mouth of Canada's St. Lawrence River have such high levels of PCBs in their blubber that under Canadian law they qualify as "toxic waste dumps".

Дата добавления: 2014-11-06