1 . Half of the world's beaches could disappear by 2100, a study published in the journal Nature Climate Change suggests.

Michalis Vousdoukas, of the European Union's Joint Research Center in Ispra, Italy, was the lead researchist. "Tourist areas which have sandy beaches as their main selling point will probably face strong consequences," he said. Aside from economic value, beaches play an important environmental role. "Sandy beaches are important habitats supporting a wide range of species. They also protect the coast from the effects of storms, so without sandy beaches other inland environments can be affected by the effects of waves and saltwater entering," Vousdoukas added.

The main causes are rising sea-level and erosion (侵蚀)from storms, the study says, which warned of the near-disappearance of almost half of the world's sandy beaches by the end of the century. Beaches in the United States will be   “greatly affected”，as will shorelines in Canada, Mexico, China and Chile. In the U. S. , beaches along the East Coast and the Gulf Coast will experience the most erosion.

Michalis Vousdoukas and other researchers used satellite images to track the way beaches have changed over the past 30 years and patterned how global warming might affect them in the future. They found that West Africa will see some of the worst losses, where more than 60% of sandy coastline may be lost in countries such as The Gambia and Guinea-Bissau. Australia will also take a hit:when the total length of sandy beach projected to be lost is analyzed, Australia would be hit the hardest, with more than 7,000 miles at risk.

1. What mainly caused the disappearance of half of the world's beaches?

A．Over population and more tourism.	B．Severe erosion and coastline losses.
C．Global warming and climate change.	D．Sea-level rise and storm destruction.

2. Which country possibly loses more than half of sandy coastline according to the study?

A．Chile.

B．The Gambia.

C．Australia.

D．The United States.

3. Why are beaches important to wildlife?

A．They can provide habitats for species.

B．They can block out waves and storms.

C．They can be popular tourist attractions.

D．They can stop erosion from happening.

4. What is the author's purpose in writing this text?

A．To introduce beaches.	B．To make a comparison.
C．To protect environment.	D．To explain a study.