Our reliance on sand is shocking—the amount we use is second only to water. As a key part of cement, asphalt (柏油) and glass, sand is essential to every aspect of our lives. Globally, humans consume up to 50 billion metric tons of sand and gravel every year, amounting to 18 kilograms per person per day.
In Asia and Africa, a construction boom has increased demand three times over the past two decades. Abundant desert sand, however, is too smooth to use for building materials, so most sand is sourced form quarries (采石场). Increasingly, it is also mined from coastal beaches, river and marine ecosystems, causing great harm to these areas.
Our increasing demand for sand now creates one of the major challenges, concludes a United Nations report. Extraction (开采)—both legal and illegal—“comes at the expense of other economic sectors, local livelihoods, and biodiversity”, according to the report. And “growth in the extraction and use of these minerals is putting pressure on the resource base and will likely lead to a ‘tragedy of the sand commons’ ”.
To avoid that tragedy, the world should focus on “reducing natural sand extraction”, the report states. One recommendation is to remove unnecessary building projects. If possible, recycle old materials. Germany, for instance, recycles 87% of its waste materials. Meanwhile, some nations are eyeing the potential to explore new sand resources. In Greenland, ice melts, leaving piles of sand on the coast, which could be exported.
“Such actions are a good start,” says Aurora Torres, and ecologist at the German Centre for Integrative Biodiversity Research. But the issue is still “understudied” and “rarely comes up in scientific circles”. “Hopefully this report will contribute to paving the way for more dialogues, interaction, and cooperation among all the sectors and actors connected by sand flows. It is time to treat sand as seriously as clean air, biodiversity, and other natural resources that nations seek to manage for the future.”
8. Which kind of sand is unsuitable for building?
A.The sand from quarries. | B.The sand from the ocean. |
C.The sand from desert. | D.The sand from rivers. |
9. What does the author intend to show in paragraph 3?
A.The functions of sand. | B.The harm of sand extraction. |
C.A tragedy of the sand commons. | D.Challenges of sand extraction. |
10. Why are Germany and Greenland mentioned in paragraph 4?
A.To show some countries’ efforts. |
B.To call for monitoring sand extraction. |
C.To persuade other countries to stop sand extraction. |
D.To convince the public of the severe situation. |
11. What can be inferred from Aurora Torres’ words?
A.Researchers take no interest in the sand issue. |
B.The world has been serious about managing sand. |
C.Sand is gaining as much attention as other natural resources. |
D.Joint efforts are needed to solve sand-related problems. |