Magnus Larsson: 將沙丘變建築

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http://dotsub.com/view/83b0c32b-b6db-4622-af11-f45ba5a35727
Magnus Larsson: 將沙丘變建築
能够来参加这次大会是件很有趣的事， 因为这是一个致力于还未出现的事物的会议， 而且我将呈现一个创意， 一个将可在非洲大陆上筑起全长 6000公里的城墙的建议。 这就形同中国长城的规模， 因此它将成为令人难以忽视的建筑。 然而构成它的部件却是不显眼的，或者说对肉眼几乎是不可见的， 那就是细菌和沙粒。
如今，作为建筑师我们被教以解决问题。 但是我不太相信建筑学上的问题， 我只相信机遇。 这就是为什么我要向你们展现一个恶兆， 和一个建筑学上的回答。 这个恶兆就是沙漠化。 而我的回答 是一条由细菌和固化沙粒建筑而成的城墙， 它将横穿整个沙漠。
在如今，沙子是一种不可思议的材料， 它充满着各种美丽的矛盾。 它简单却又复杂。 和平却也暴力。 它虽为永恒却也无常， 它有着无穷尽的迷人魅力。 这个世界，时时刻刻都有 成千上万的沙粒在产生。 那是一个循环过程。 岩石和山脉消逝之时， 沙粒于焉诞生。 一些沙粒随后又自然粘结形成岩石。 随着岩石风化，新的沙粒形成。 其中一些沙粒 会大规模积聚， 形成沙丘。
从某种程度上来说，静态的岩石山脉 变成了移动的沙粒山脉。 但是，移动的山脉是危险的。我来试着解释一下原因。 地球表面超过三分之一的陆地处于干旱地区。 其中一些是荒漠， 其它的则被沙完全覆盖。 就在撒哈拉沙漠的南边我们发现了沙赫尔。 这个名字的意思是“沙漠的边缘”。 这是和沙漠化联系最紧密的地区。 也就是在这，在六十年代晚期和七十年代早期， 干旱让三百万人民 只能依靠应急救援食品来生存， 并夺去了总计大约250000人的生命。
这样的大灾难正伺机卷土重来。 但它却很少受到人们的注意。 在我们日益加速的媒体文化中， 沙漠化是如此缓慢 而难以登上头版头条。 它一点也不像海啸或卡特里娜（飓风）： 很少有哭泣的孩子和被摧毁的房屋。 然而，沙漠化 对所有国家都是一个主要的威胁。 大约110个国家 和全球70%左右的农用旱地都受其影响。
它严重地威胁了数以万计的人 的生计问题， 尤其是在非洲和中国。 很大程度上这个问题是我们人类自找的， 源于我们对稀有资源的滥用。 为此，我们得到了气候变化。 我们得到了干旱， 日益严重的沙漠化、 食物系统崩溃、水资源短缺、 饥荒、被迫的移民、 政治动荡、战争和危机。 如果我们不严肃对待， 那一切的不幸将在现实上演。 那么，它现在离我们有多远呢？
我试着去尼日利亚南部的索科托州 寻找答案。 这的沙丘以每年大约600米的速度向南移动。 撒哈拉沙漠每天几乎要吞噬掉一米的可耕地， 把人赶出他们的房屋。 我在这——左边第二个—— （笑声） 和Gidan-Kara的长老一起。 那是索科托州外的一个小村庄。
1987年他们不得不搬离了这个村子， 因为一座巨大的沙丘正威胁着将它吞没。 所以，他们一间屋子一间屋子地搬走了整个村庄。 这是他们村子曾经所在的地方。 爬到那座沙丘的顶部大约花掉了我们10分钟时间。 这说明了他们为什么不得不搬到一个更安全的地方。 那就是沙漠化所导致的 被迫的迁移。 如果你碰巧住在离沙漠边界很近的地方， 你几乎能计算还有多久 你就得带着你的孩子离开， 遗弃你的房屋和生活，正如你所知道的。
现在，沙丘只覆盖了我们大约五分之一的荒漠。 但是，如果我们想要阻止流沙的话 那些极端的环境会是很好的地方。 四年前，23个非洲国家 联合起来建造撒哈拉沙漠长城。 一个项不可思议的工程，它最初的计划 是种植一条西起毛里塔尼亚东至吉布提 贯穿非洲大陆的 防护林带。 如果你想要停止沙丘移动 你就必须确保能够阻止沙粒 从沙丘顶部崩塌下来。 有一个很好的也是最有效的方法 就是用某种沙子捕手。 树或者仙人掌就不错。 但是种树面临着一个问题， 那个地区的人太穷， 他们把树砍倒当柴火了。
现在，除了种树然后指望着它们别被砍掉 我们有了另一种选择。 我所提倡的岩石长城从本质上做了三件事。 它增加了沙丘表面纹理的粗糙度， 把沙粒粘结在一起。 它为树木的生存提供了物理支撑结构， 它还在沙丘的内部创造了 可供居住的空间。 如果人们居住在这道绿色的屏障内， 他们就能帮着照料这些树，保护它们免受人类 和一些自然力量的破坏。 在沙丘里我们能找到阴凉的地方。 我们开始收获（沙粒的）凝结， 并开始从内部将沙漠绿化。
沙丘已经差不多有点像现成的建筑了， 我们需要做的只是固化所需的部分， 然后挖掘沙子， 构筑我们的建筑。 我们既可以用手挖掘 也能让风来帮我们。 风把沙粒搬运上来 再把多余的沙从我们的建筑上搬走。
但是，到现在，你们或许会问 我打算怎样把一座沙丘固化呢？ 我们又怎样把沙粒粘合在一起？ 答案就是，或许，你可以用这些家伙， 巴氏芽孢杆菌， 一种能从湿地和沼泽中 轻松获取的微生物。 它带着一堆疏松砂岩 并能用它们制造砂岩。 这些来自美国微生物学会的照片向我们展示了这一过程。
所发生的是，你把巴氏芽孢杆菌倒在一堆沙上， 它开始填充沙粒间的间隙。 由一个化学过程产生方解石， 方解石是一种天然的水泥， 能把沙粒粘结在一起。 整个粘结过程大概需要24个小时。 我从加州大学一个叫Jason DeJong的教授那里学到了这些。 他成功地在1400分钟里完成了这个实验。 在这，我扮演起了这位疯狂的科学家的角色， 和这个疯子一起在伦敦的伦敦大学学院工作， 尝试着固化它们。
那么，这个项目要花费多少呢？ 我一点也不像个经济学家， 但是，我做了一个——照字面来说的——封底运算…… （笑声） 看起来一立方米粘结物 要耗费我们90美元左右。 最初我们需要用60美元来买细菌， 之后你就不用再为细菌花钱了， 那样算下来的话一立方米带细菌的沙子 大约是11美元。
我们该怎么构建想这样的东西呢？ 我这就为你们展示两种选择。 第一是创造一种气球一样的结构， 把它装满细菌，然后用沙子磨洗它， 冲击它，可以说就是把细菌散播进沙里去固化它。 等过几年， 从长远打算， 我们把那部分沙漠绿化。
第二种选择是用喷桩。 我们把喷桩插进沙丘里， 再创造一个原始的细菌表面。 然后把这些喷桩从沙丘里拔出来。 以沙为模子， 我们几乎能在沙丘内部创造任何我们想要的形状。 所以，我们有了一个把沙变成砂岩的办法， 能在沙丘内部创造可居住的空间。
但是，它们该是什么样子的呢？ 嗯，我的建筑形态让我有些激动，它是依靠风化形成的， 看起来有点像这样，这是它的一个模型。 这些是我在索科托州建立的洞穴岩石结构。 我意识到如果我把它们像鱼鳞一样排列起来，它们就能为我提供 很好的空间质量， 无论是通风，温度还是其它事。 现在，在正常控制范围内，这些结构的一部分 很明显会被自然侵蚀掉。 那些细菌起作用了。 我想着确实是创造了一种无尽的美。 在这里的确有一些东西 是非同凡响的。 我们看到了用巴氏芽孢杆菌来把沙漠 雕刻成人间乐土的结果， 如果你喜欢，也可以说是痕迹。
有人担心 这种传播会不会不受控制， 那些细菌会杀死它们碰到的任何东西。 那绝对是错误的。 这是一个自然过程。它现在也在自然界中进行着。 一旦我们停止喂养细菌，它们就会死去。 所以，这些是—— 用沙漠本身建造的 建筑学上的抵抗沙漠化结构。 来自于沙的阻止沙前进的设备。 到本世纪末，全世界有可能失去 三分之一的可耕地。 在人口数量空前飞涨 食物需求日益增加的时期，这几乎是个灾难。 坦白说我们正把目光投向沙漠。
如果没有什么其它的事，我想为这个计划开始一个讨论。 但是，如果要我在TED许一个愿， 我希望它能被切实地建造起来， 开始建造这条可以居住的长城， 这座很长很长，但却很窄的沙漠之城， 建在沙丘自己体内。 它不仅能承载树木， 更能将人和各个国家联系在一起。 最后，我想给你们展示一个这个结构的动画， 并送给你们一句博尔赫斯的话。
博尔赫斯说：“没有什么是建筑在岩石上， 任何东西都建于沙子之上的， 但我们必须把沙子当作石头来建筑。”
现在，这个计划的许多细节还有待进一步研究， 有政治的，实用性的，道德的，经济的。 我的设计——将带领你们深入“兔窝”—— 在现实中充满了 困难和挑战。 但是，这只是一个开始，一个展望。 如博尔赫斯所说，这是沙子。 我想，现在是把沙子 变成岩石的时候了。
谢谢。 （掌声）


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Magnus Larsson: Turning dunes into architecture
It's a bit funny to be at a conference dedicated to things not seen, and present my proposal to build a 6,000-kilometer-long wall across the entire African continent. About the size of the Great Wall of China, this would hardly be an invisible structure. And yet it's made from parts that are invisible, or near-invisible to the naked eye, bacteria and grains of sand.

Now, as architects we're trained to solve problems. But I don't really believe in architectural problems; I only believe in opportunities. Which is why I'll show you a threat, and an architectural response. The threat is desertification. My response is a sandstone wall made from bacteria and solidified sand, stretching across the desert.

Now, sand is a magical material of beautiful contradictions. It is simple and complex. It is peaceful and violent. It is always the same, never the same, endlessly fascinating. One billion grains of sand come into existence in the world each second. That's a cyclical process. As rocks and mountains die, grains of sand are born. Some of those grains may then cement naturally into sandstone. And as the sandstone weathers, new grains break free. Some of those grains may then accumulate on a massive scale, into a sand dune.

In a way, the static, stone mountain becomes a moving mountain of sand. But, moving mountains can be dangerous. Let me try and explain why. Dry areas cover more than one third of the Earth's land surfaces. Some are already deserts; others are being seriously degraded by the sand. Just south of the Sahara we find the Sahel. The name means "edge of the desert." And this is the region most closely associated with desertification. It was here in the late '60s and early '70s that major droughts brought three million people to become dependent upon emergency food aid, with about up to 250,000 dying.

This is a catastrophe waiting to happen again. And it's one that gets very little attention. In our accelerated media culture, desertification is simply too slow to reach the headlines. It's nothing like a tsunami or a Katrina: too few crying children and smashed up houses. And yet desertification is a major threat on all continents, affecting some 110 countries and about 70 percent of the world's agricultural drylands.

It seriously threatens the livelihoods of millions of people, and especially in Africa and China. And it is largely an issue that we've created for ourselves through unsustainable use of scarce resources. So, we get climate change. We get droughts, increased desertification, crashing food systems, water scarcity, famine, forced migration, political instability, warfare, crisis. That's a potential scenario if we fail to take this seriously. But, how far away is it?

I went to Sokoto in northern Nigeria to try and find out how far away it is. The dunes here move southward at a pace of around 600 meters a year. That's the Sahara eating up almost one meter a day of the arable land, physically pushing people away from their homes. Here I am -- I'm the second person on the left -- (Laughter) with the elders in Gidan-Kara, a tiny village outside of Sokoto.

They had to move this village in 1987 as a huge dune threatened to swallow it. So, they moved the entire village, hut by hut. This is where the village used to be. It took us about 10 minutes to climb up to the top of that dune. Which goes to show why they had to move to a safer location. That's the kind of forced migration that desertification can lead to. If you happen to live close to the desert border, you can pretty much calculate how long it will be before you have to carry your kids away, and abandon your home, and your life as you know it.

Now, sand dunes cover only about one fifth of our deserts. And still, those extreme environments are very good places if we want to stop the shifting sands. Four years ago, 23 African countries came together to create the Great Green Wall Sahara. A fantastic project, the initial plan called for a shelter belt of trees to be planted right across the African continent, from Mauritania in the west, all the way to Djibouti in the east. If you want to stop a sand dune from moving what you need to make sure to do is to stop the grains from avalanching over its crest. And a good way of doing that, the most efficient way, is to use some kind of sand catcher. Trees or cacti are good for this. But, one of the problems with planting trees is that the people in these regions are so poor that they chop them down for firewood.

Now there is an alternative to just planting trees and hoping that they won't get chopped down. This sandstone wall that I'm proposing essentially does three things. It adds roughness to the dune's surface, to the texture of the dune's surface, binding the grains. It provides a physical support structure for the trees, and it creates physical spaces, habitable spaces inside of the sand dunes. If people live inside of the green barrier they can help support the trees, protect them from humans, and from some of the forces of nature. Inside of the dunes we find shade. We can start harvesting condensation, and start greening the desert from within.

Sand dunes are almost like ready-made buildings in a way. All we need to do is solidify the parts that we need to be solid, and then excavate the sand, and we have our architecture. We can either excavate it by hand or we can have the wind excavate it for us. So, the wind carries the sand onto the site and then it carries the redundant sand away from the structure for us.

But, by now, you're probably asking how am I planning to solidify a sand dune? How do we glue those grains of sand together? And the answer is, perhaps, that you use these guys, Bacillus pasteurii, a micro-organism that is readily available in wetlands and marshes, and does precisely that. It takes a pile of loose sand and it creates sandstone out of it. These images from the American Society for Microbiology show us the process.

What happens is, you pour Bacillus pasteurii onto a pile of sand, and it starts filling up the voids in between the grains. A chemical process produces calcite, which is a kind of natural cement that binds the grains together. The whole cementation process takes about 24 hours. I learned about this from a professor at U.C. Davis called Jason DeJong. He managed to do it in a mere 1,400 minutes. Here I am, playing the part of the mad scientist, working with the bugs at UCL in London, trying to solidify them.

So, how much would this cost? I'm not an economist, very much not, but I did, quite literally, a back of the envelope calculation -- (Laughter) -- and it seems that for a cubic meter of concrete we would have to pay in the region of 90 dollars. And, after an initial cost of 60 bucks to buy the bacteria, which you'll never have to pay again, one cubic meter of bacterial sand would be about 11 dollars.

How do we construct something like this? Well, I'll quickly show you two options. The first is to create a kind of balloon structure, fill it with bacteria, then allow the sand to wash over the balloon, pop the balloon, as it were, disseminating the bacteria into the sand and solidifying it. Then, a few years afterwards, using permacultural strategies, we green that part of the desert.

The second alternative would be to use injection piles. So, we pushed the piles down through the dune, and we create an initial bacterial surface. We then pull the piles up through the dune and we're able to create almost any conceivable shape inside of the sand with the sand acting as a mold as we go up. So, we have a way of turning sand into sandstone, and then creating these habitable spaces inside of the desert dunes,

But, what should they look like? Well, I was inspired, for my architectural form, by tafoni, which look a little bit like this, this is a model representation of it. These are cavernous rock structures that I found on the site in Sokoto. And I realized that if I scaled them up, they would provide me good spatial qualities, for ventilation, for thermal comfort, and for other things. Now, part of the formal control over this structure would be lost to nature, obviously, as the bacteria do their work. And I think this creates a kind of boundless beauty actually. I think there is really something in that articulation that is quite nice. We see the result, the traces, if you like, of the Bacillus pasteurii being harnessed to sculpt the desert into these habitable environments.

Some people believe that this would spread uncontrollably, and that the bacteria would kill everything in its way. That's not true at all. It's a natural process. It goes on in nature today. and the bacteria die as soon as we stop feeding them. So, there it is -- architectural antidesertification structures made from the desert itself. Sand-stopping devices, made from sand. The world is likely to lose one third of its arable land by the end of the century. In a period of unprecedented population growth and increased food demands, this could prove disastrous. And quite frankly, we're putting our heads in the sand.

If nothing else, I would like for this scheme to initiate a discussion. But, if I had something like a TED wish, it would be to actually get it built, to start building this habitable wall, this very very long, but very narrow city in the desert, built into the dunescape itself. It's not only something that supports trees, but something that connects people and countries together. I would like to conclude by showing you an animation of the structure, and leave you with a sentence by Jorge Luis Borges.

Borges said that, "Nothing is built on stone, everything is built on sand, but we must build as if the sand were stone"

Now, there are many details left to explore in this scheme, political, practical, ethical, financial. My design, as it takes you down the rabbit hole, is fraught with many challenges and difficulties in the real world. But, it's a beginning, it's a vision. As Borges would have it, it's the sand. And I think now is really the time to turn it into stone. Thank you. (Applause)