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  • You may think of sand as part of your beach vacation, but

  • it's used for more than just sand castles. It's a commodity

  • like oil and copper and gold.

  • If you look around you, everything is made of sand.

  • It's a pretty crucial commodity. And even though

  • sand can be found in nearly every single country on Earth,

  • we could soon face a sand shortage. Turns out, sand is

  • only second to water as the most consumed raw material

  • worldwide. Sand mining is the largest mining industry in the

  • world. And yet, it flies under the radar, largely unregulated

  • and unknown.

  • All of society is basically built on sand and how come

  • there's no monitoring on that? And how come people are ready

  • to kill someone else for sand in some regions?

  • It's used in construction, like critical infrastructure,

  • and President Biden is diverting a lot of his

  • attention to America's infrastructure. Sand is also

  • used in chemical production, water filtration, fracking,

  • and of course, glass. So, all of your windows, computers and

  • cell phones.

  • You know, it's literally everywhere we're driving on

  • it. We're sitting in it. We're looking through it. It's

  • absolutely extraordinary. I'm really starting to be

  • concerned about what happens if we don't have this anymore.

  • Sand use around the world has tripled in the last 20 years.

  • That's far greater than the rate that sand is being

  • replenished.

  • One of the biggest sustainability challenges of

  • the 21st century simply because of the scale of the

  • problem. The more I learned about it, the more alarmed I

  • became.

  • So, the world is facing a sand crisis. And that's a problem.

  • I know what you're thinking: Yes, sand is everywhere. How

  • can there be a shortage?

  • Actually, in some places, the world was running out, and

  • it's such a hard concept to get your head around because

  • you think of coastlines and expansive deserts and just see

  • so much of it, that to think of it not being there is very,

  • very challenging.

  • It's a classic example of the tragedy of the commons. An

  • economic concept where everyone is incentivized to

  • keep consuming a natural resource, even if it ends in

  • overconsumption, and ultimately, the total

  • depletion of that resource,

  • So is it a crisis or not? And that's one of the hard things

  • with this topic, that it's a problem that manifests in very

  • different ways in very different places. So, I bet

  • you if you were in a community where sand mining is going on

  • like this is not a surprise to you at all.

  • I grew up in Bangalore in South India. As I grew up, I

  • constantly read reports about rivers being decimated because

  • of sand mining. And at the same time, I saw hundreds and

  • hundreds of sand filled trucks flying up and down the road in

  • the city of Bangalore. That was when the city was being

  • transformed to the Silicon Valley of India basically. A

  • construction boom happening all over and all that sand was

  • coming from precious places.

  • Construction has caused a steep increase in demand for

  • sand. And, a lot of sand is being extracted from oceans

  • and rivers.

  • It's not just shortage in the market at shortage in the

  • natural environment that has to be talked about. The

  • concern is that there's literally not enough sand on

  • coastlines in a context of rising sea levels and

  • increased storms.

  • Sand crafted by water is more valuable than desert sand

  • eroded by wind. That makes desert sand to smooth it

  • doesn't bind together as well as other types of sand. Sand

  • is sourced and extracted from seabeds, coastlines, quarries,

  • or rivers is more angular, so it locks together. And, that's

  • important because this kind of sand is a key ingredient in

  • cement and concrete.

  • And concrete is made up of 65 to 75%, sand and gravel.

  • Then there's glass, sand, gravel and rock crushed

  • together or melted down to make the glass used in every

  • window computer screen and smartphone

  • Glass is about 70% silica sand. So, there are very

  • specific types of sand that are required for specific

  • uses. And these places are limited.

  • Even the production of silicon computer chips uses sand, but

  • extracting sand can damage the environment.

  • Extractions of marine sand, coastal sand, beach... beach

  • is the worst. And rivers is something that is leading to

  • tremendous environmental impact

  • For oceans... Well, imagine you scrape sand off the bottom

  • of the ocean. That's going to affect the microorganisms that

  • live in the ocean floor. That's going to affect the

  • fish that eat the microorganisms, and then the

  • fish that eat those fish. Basically, the sand removal of

  • affects entire ecosystem. Sand is the most extracted resource

  • in the world by volume, surpassing even fossil fuels.

  • Actually, even extracting oil and gas uses a lot of sand,

  • like in fracking. And yet sand has been easy to ignore.

  • Essentially, it's invisible in our minds and in the way that

  • we manage the resource. We don't think about it like a

  • strategic resource. And yet it is everywhere in our societies

  • and our economies.

  • And as a result, we're wasting these resources. And in 2019,

  • we produced this report, which was submitted to the United

  • Nations Environmental Assembly, and it was used for

  • making a new resolution on a global mineral governance, and

  • it was adopted by all countries. And it was first

  • time that countries recognize that we have a problem with

  • sand.

  • This concept of panicking, it reminds me a little bit of

  • Great Thunberg talking about I want you to panic

  • I want you to panic.

  • When she was talking to the World Economic Forum, and it

  • didn't quite go that far.

  • Panicking will never be a solution. We will need sand

  • forever. It's something that we need a lot. So, we need to

  • be much wiser on the way we use the resource.

  • Right now, it's not really possible to monitor global

  • sand use.

  • We just don't know enough. We don't have that global picture

  • or that holistic picture of the extraction sites, the

  • extraction volumes, where it's coming from, where it's going

  • to how it's being used.

  • But it can be measured indirectly.

  • Construction is the biggest demand sector. We know that.

  • There's a very, very good correlation between the use of

  • sand and cement. The UN estimates that 4.1 billion

  • tons of cement is produced every year. And it takes

  • roughly 10 tons of sand to create one ton of cement. Do

  • the math, and...

  • 41 billion tons of sand and gravel

  • That's enough to build a wall nearly 89 feet high by 89 feet

  • wide, that wraps around the planet every year. And that's

  • just sand used in cement production. Demand for cement

  • is driven primarily by China, where construction is booming.

  • In the last two decades, the amount of sand that we've been

  • using has been multiplied by three. More than 55, 58% is

  • being used in in China.

  • Part of the problem is some countries don't have

  • regulations in place.

  • And, then you have people who take sand from the beach. Take

  • sands from anywhere because they have to make a living. If

  • you have a shovel and access to your truck, you an entrepre

  • eur, you taking sand and you re selling it

  • in some parts of the world, there are even sand mafias

  • There are sand mafia. It is a problem. That's for sure. And

  • so in some countries where the governance, the policies do

  • not exist, it's not even illegal to take sand.

  • Plus, the world faces a rapidly growing population. By

  • 2050, the world could reach nearly 10 billion people.

  • Africa is going to see its population doubling from now

  • to 2050. People are shifting from their villages to join

  • the cities that will request more infrastructure in the

  • cities. All of that will request the amount of sand

  • Sand can't be extracted or sourced sustainably to meet

  • demand from a world of 10 billion people without

  • effective planning and regulation.

  • If you are a local government, you need to have a solid land

  • planning. Identify where the sand and gravels should be

  • extracted.

  • The challenge is understanding where it's okay to take it

  • from and how much

  • So it's important to plan ahead and to plan

  • alternatives.

  • It's a time for innovations in this area.

  • There's no one size fits all solution for the looming sand

  • crisis

  • we need many solutions that, you know, will also work

  • together. It's not going to be like one alternative material

  • is going to make the difference. I think it's going

  • to have to be a big group effort, a big push

  • collectively to figure this out.

  • Finding alternatives to sand, including recycled materials,

  • may help

  • We can recycle concrete so that we're not wasting that by

  • dumping these resources as a waste. Because it's not a

  • waste. It can be recycled

  • Our current economy is geared towards mining this material

  • at extreme cost to the environment and to society,

  • but that isn't factored in. We kind of build things and then

  • at the end of life, we simply toss it in the landfill. So

  • it's a very linear economy. But changing this to a

  • circular economy can be a significant solution. And the

  • circular economy is a way that keeps materials in use for

  • longer.

  • We can improve extracting in a better way by doing

  • environmental impact assessment prior to mine then

  • ining in appropriate way respe ting social and envir

  • nmental conditions, then we ca reduce the amount of sand

  • y being much more clever on ho we use it, so that means

  • planning for longer term in te ms of having a building that

  • s not done after 20, 30 yea s. We extend that to 50, 60 y

  • ars.

  • Sand is a finite resource. Every time we remove sand from

  • the ecosystem, we are taking away critical habitat. We ar

  • taking away coastal securit because sand along the coas

  • acts as a storm buffer. S , when we extract sand, it com

  • s at a cost and this needs to e really really balanced wi

  • h the needs of futu e generation

You may think of sand as part of your beach vacation, but

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为什么世界快要枯竭了(Why The World Is Running Out Of Sand)

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    joey joey 發佈於 2021 年 05 月 13 日
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