"It's this time of year when the weather starts warming up and frogs start breeding - but they haven't been breeding," says John Wilkinson, research and monitoring officer at the Amphibian and Reptile Conservation Trust (ARC).
Amphibians (两栖动物) are just one of the groups of animals that nature observers fear may have problems reproducing this year, as groundwater levels are even lower now than in the infamously dry summer of 1976, according to the Department for Environment, Food and Rural Affairs (Defra). According to the UK's Centre for Hydrology and Ecology the average rainfall so far this winter has been the lowest since 1972.
"If ponds dry up totally," says Mr. Wilkinson, "you could have lots of dead tadpoles." Drier and windier conditions could also make it more difficult for juvenile amphibians to survive their journeys between wet habitats.
But Peter Brotherton, the biodiversity manager for Natural England, says that "drought is part of nature's cycle", and, at present, a lot of animals, plants and insects are still in hibernation. This means that the population picture is unclear. "However, when we get extreme events, we get animals dying," he says. "And what is worrying is that normally at this time of year we expect soil to be near saturation（湿润）after winter."
Charlie Kitchin, the RSPB's site manager of the Nene Washes in Cambridgeshire, says the 2,000-acre wetland and grassland area is now struggling following two winters with relatively little winter rain and no flooding. One species that could suffer, he says, is the black-tailed godwit（黑尾豫）. "There are only 50 breeding pairs in the country, and we have 40 of them, and everything is bone-dry," Mr Kitchin says.
But one bad nesting season, he says, is "not the end of the world". "One of the features of flood plains is that they're volatile anyway," he adds. "But if they fail to breed another year, the population is likely to dip again."
71. According to the passage animals may have problems reproducing this year mainly due to ________.
A. drought B. hibernation
C. windier conditions D. extreme events
72. What really worries Peter Brotherton is that ________.
A. drought is part of nature’s cycle
B. animals are still in hibernation
C. soil at this time is far from saturation
D. the population of animals is still unclear
73. Which of the following is NOT true of Charlie Kitchin’s words?
A. Drought has so far continued for two winters.
B. Animals could survive one bad nesting season.
C. The black-tailed godwit is in danger of extinction.
D. 40 black-tailed godwits live in the Nene Washes.
74. The underlined word volatile in the last paragraph can be replaced by ________.
A. losing water B. undergoing changes
C. breeding animals D. suffering flood
75. It can be learnt from the text that ______________.
A. groundwater levels this summer are lower than those of 1976
B. the average rainfall this year has been the lowest since 1972
C. windier conditions could also cause some amphibians’ death
D. flooding plays no useful role in wetlands and grasslands