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  • The world’s sands are shifting, by the lorryload.

  • According to a recent UN report, up to 50 billion tonnes of sand a year is being mined,

  • dredged and even stolen to satisfy the global appetite for infrastructure.

  • And it’s disappearing faster than it can be replenished.

  • The plunder of lakes, rivers and coastal areas cuts biodiversity, destroys fishing communities,

  • causes pollution, lowers the water table and increases the risk of flooding.

  • There are two types of sand.

  • The first is mineral sand, which comes mainly from riverbeds and coastal areas like beaches.

  • The second type is aggregates, that’s a generic term for crushed rock, sand and gravel.

  • It’s coarser, easier to bind, and the construction industry loves it.

  • The plunder tends to happen in countries with rapidly growing infrastructure and where rules

  • are lacking, not enforced, or where there’s corruption.

  • The UN now wants to curb the problem, starting with improved governance.

  • Transporting sand is expensive, so material tends to be used near to where it’s removed.

  • Tracking where infrastructure is springing up could provide clues about which ecosystems

  • might be targeted.

  • Another option is to find alternative materials, like desert sand. It’s a huge resource,

  • but the challenge is, it’s smooth and fine-grained.

  • An Imperial College student start-up called Finite, is trying to develop a building material

  • out of desert sand, but the reusable, biodegradable composite is so far only suitable for temporary

  • structures.

  • There are no simple answers, but as it slowly ebbs away, something needs to be done about

  • the great sand grab.

The world’s sands are shifting, by the lorryload.

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B2 中高級

遏止大肆搶奪沙子的行為|可持續發展的反思 (Curbing the great sand grab | Rethink Sustainability)

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    林宜悉 發佈於 2021 年 01 月 14 日
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