10.Dragging a sleigh loaded with enough presents for the world's children can be no easy skill.But,since ancient times,the Christmas Eve duty has been performed with distinction by a team of beloved reindeer(馴鹿).
Soon,however,Santa Claus may have to start looking around for a stronger type of animal,as a new research shows the species is becoming increasingly puny.A 16-vear survey on the arctic Norwegian island of Svalbard found the reindeer there have declined in weight by an alarming 12 percent.
The reduction in average body-mass is being blamed on global warming.In the research presented lately at a meeting of the British Ecological Society in Liverpool,scientists have explained how rising temperatures are robbing female reindeer of nutrients during important periods of pregnancy.a(chǎn)re becoming starved,causing them to abort their babies or giving birth to much lighter young.
Snow in Svalbard typically covers the ground for eight months of the year,which,combined with low temperatures,limits grass growth to June and July.But as summer temperatures have increased by around 1.5°C,grass has become more productive,allowing female reindeer to gain more weight by the autumn and therefore to have more babies.However,wanner winters have brought with them greater rainfall which freezes when it settles on the snow.Reindeer can often access the poor food sources beneath the snow by clearing it away with their antlers(鹿角),but they cannot break through the hard ice.As a result,female reindeer are becoming starved,causing them to abort their babies or giving birth to much lighter young.
Despite the findings,reindeer appear to be suffering less from the effect of climate change than some other arctic species.Last week the scientists warned that a third of the world's polar bears could disappear in the next 40 years.
32.Which of the following can replace the underlined word"puny"in Paragraph 2?D
A.strong B.mature C.heavy D.weak
33.Why do female reindeer become fat in autumn?C
A.The temperature is getting low.
B.They give birth to more babies.
C.Grass has grown well since summer.
D.They often break through the hard ice.
34.What can we infer from the text?B
A.Climate change has little effect on reindeer.
B.Polar bears suffer more from climate change.
C.Reindeer have no trouble finding food in winter.
D.Polar bears will disappear in the near future.
35.What does the text mainly talk about?B
A.The Christmas Eve duty will still be carried out by reindeer.
B.Reindeer has decreased in weight owing to global warming.
C.Global warming contributes to more young reindeer.
D.Many arctic species are at the risk of dying out.