1 . With no special equipment, no fences and no watering, two abandoned agricultural fields in the UK have been rewilded (重新野化), in large part due to the efforts of jays, which actually “engineered” these new woodlands. Researchers now hope that rewilding projects can take a more natural and hands-off approach and that jays can shed some of their bad reputations.
The two fields, which researchers have called the New Wilderness and the Old Wilderness, had been abandoned in 1996 and 1961 respectively. The former was a bare field, while the latter was grassland—both lay next to ancient woodlands. Researchers had suspected that the fields would gradually return to wilderness, but it was impressive to see just how quickly this happened, and how much of it was owed to birds.
Using aerial data, the researchers monitored the two sites. After just 24 years, the New Wilderness had grown into a young, healthy wood with 132 live trees per hectare, over half of which (57%) were oaks. Meanwhile, the Old Wilderness resembled a mature woodland after 39 years, with 390 trees per hectare.
“This native woodland restoration was approaching the structure (but not the species composition) of long-established woodlands within six decades,” the researchers explained in the study.
Part of this reforestation was done by the wind, and researchers suspect that previous ground disturbance may have aided the woodland establishment—which is good news, as it would suggest that agricultural areas may be reforested faster than anticipated. However, animals—Eurasian jays, thrushes, wood mice, and squirrels—also played an important role in helping the forests take shape. This handful of species provided much of the natural regeneration needed for the forest to develop. Jays, in particular, seem to have done a lot of heavy lifting.
1. What does the underlined word “shed” in Paragraph 1 refer to?A.Be opposed to. |
B.Be ashamed of. |
C.Get used to. |
D.Get rid of. |
A.The scale of the woodlands. |
B.The diversity of the fields. |
C.The rate of the changes. |
D.The frequency of the wilderness. |
A.The woodland restoration was approaching the structure of long-established ones. |
B.Much of the wilderness of the fields was owed to birds. |
C.Previous ground disturbance aided the woodland establishment. |
D.How quickly the fields returned to wilderness over time. |
A.The essential role of humans in the reforestation. |
B.The factors that contribute to the reforestation. |
C.The importance of woodland establishment. |
D.The threats faced by a handful of wild animals. |
The classical gardens of Suzhou, Jiangsu province, date back to the 6th century
Built in the 11th century on the site of an
The classical gardens of Suzhou
3 . Mount Tai, located just north of Tai’an city in East China’s Shandong Province, is a mountain of historical and cultural
Among the Five Sacred Mountains (the other four are Heng Mountain of Hunan Province, Hua Mountain of Shaanxi Province, Song Mountain of Henan Province and Heng Mountain of Shanxi Province), Mount Tai is only the third highest. Why is it seen as the
In absolute terms, Mount Tai cannot be considered as the highest of China’s mountains, but because it is
Many Chinese emperors climbed to the top for enthronement (登基) or other significant ceremonies in ancient China, for they considered it to be a
Mount Tai is famous for its various stone inscriptions, which are the works of either ancient emperors or celebrities. The stone inscriptions
A.evidence | B.significance | C.confidence | D.existence |
A.partner | B.member | C.leader | D.laggard |
A.close | B.far | C.remote | D.proper |
A.absolute | B.relative | C.real | D.perfect |
A.altitude | B.width | C.longitude | D.attitude |
A.However | B.Therefore | C.Otherwise | D.Moreover |
A.chance | B.change | C.death | D.renewal |
A.gift | B.symbol | C.beginning | D.call |
A.look at | B.go through | C.look for | D.go back |
A.preserved | B.ruined | C.collected | D.hid |
A.newspapers | B.information | C.articles | D.advertisements |
A.combine | B.change | C.stop | D.increase |
A.exciting | B.famous | C.delicate | D.rough |
A.importance | B.magnificence | C.possibility | D.difference |
A.powerless | B.pale | C.weak | D.forceful |
4 . By the end of the century, if not sooner, the world’s oceans will be bluer and greener thanks to a warming climate, according to a new study.
At the heart of the phenomenon lie tiny marine microorganisms(海洋微生物) called phytoplankton. Because of the way light reflects off the organisms, these phytoplankton create colourful patterns at the ocean surface. Ocean colour varies from green to blue, depending on the type and concentration of phytoplankton. Climate change will fuel the growth of phytoplankton in some areas, while reducing it in other spots, leading to changes in the ocean’s appearance.
Phytoplankton live at the ocean surface, where they pull carbon dioxide(二氧化碳) into the ocean while giving off oxygen. When these organisms die, they bury carbon in the deep ocean, an important process that helps to regulate the global climate. But phytoplankton are vulnerable to the ocean’s warming trend. Warming changes key characteristics of the ocean and can affect phytoplankton growth, since they need not only sunlight and carbon dioxide to grow, but also nutrients.
Stephanie Dutkiewicz, a scientist in MIT’s Center for Global Change Science, built a climate model that projects changes to the oceans throughout the century. In a world that warms up by 3℃, it found that multiple changes to the colour of the oceans would occur. The model projects that currently blue areas with little phytoplankton could become even bluer. But in some waters, such as those of the Arctic, a warming will make conditions riper for phytoplankton, and these areas will turn greener. “Not only are the quantities of phytoplankton in the ocean changing. ” she said, “but the type of phytoplankton is changing.”
And why does that matter? Phytoplankton are the base of the food web. If certain kinds begin to disappear from the ocean, Dutkiewicz said, “it will change the type of fish that will be able to survive.” Those kinds of changes could affect the food chain.
Whatever colour changes the ocean experiences in the coming decades will probably be too gradual and unnoticeable, but they could mean significant changes. “It’ll be a while before we can statistically show that the changes are happening because of climate change,” Dutkiewicz said, “but the change in the colour of the ocean will be one of the early warning signals that we really have changed our planet.”
1. What are the first two paragraphs mainly about?A.The various patterns at the ocean surface. |
B.The cause of the changes in ocean colour. |
C.The way light reflects off marine organisms. |
D.The efforts to fuel the growth of phytoplankton. |
A.Sensitive. | B.Beneficial. | C.Significant. | D.Unnoticeable. |
A.Phytoplankton play a declining role in the marine ecosystem. |
B.Dutkiewicz’s model aims to project phytoplankton changes. |
C.Phytoplankton have been used to control global climate. |
D.Oceans with more phytoplankton may appear greener. |
A.To assess the consequences of ocean colour changes. |
B.To analyse the composition of the ocean food chain. |
C.To explain the effects of climate change on oceans. |
D.To introduce a new method to study phytoplankton. |