Precedent #4 Dune: Arenaceous Anti-Desertification Architecture -Magnus Larsson

From the Holcim Foundation Website, in the words of Magnus Larsson:

"This project investigates adaptive (as opposed to mitigatory)

strategies leading to the creation of a climate-conscious

architecture that responds to the extreme environments

of tomorrow’s globally-warmed world. Highly speculative

yet buildable, the scheme aims to fi nd innovative solutions

to combat desertifi cation in the Sahel region of Africa, where

sand dunes are currently moving southward at a breathtaking

pace of around 600m per year, ruining the land and making

it impossible for the inhabitants of this area to make a

living or even stay in their homes.

The forced migration of desertifi cation refugees is perhaps

more threatening in Nigeria than anywhere else. With a population

of over 140 million people, Nigeria is the most populous

country in Africa, with serious desertifi cation issues

throughout its northern states. It was Nigeria’s former president,

Olusegun Obasanjo, who initiated the anti-desertifi -

cation Green Wall Sahara initiative in 2005. This pan-African

scheme seeks to plant a shelterbelt across the continent, from

Mauritania in the west to Djibouti in the east, in an attempt

to stop the dunes from migrating. The trees are being planted

right now.

An architectural response to this campaign would be to go

beyond the mere planting of a mitigatory shelterbelt. Habitable

spaces can be created in close proximity to the trees. By

cutting through the sand dunes and digging down to fi nd

water and shade, an artifi cial oasis can be formed underground.

The sand is solidifi ed using bacillus pasteurii, a microorganism

with which professor Jason DeJong has turned

sand into sandstone in a mere 1,400 minutes. This technology

of organically cementing networks of sand dunes into

habitable barriers that stop the desert from spreading has

never been proposed before, but on hearing about this project,

the professor was enthusiastic: “I do think the application

you are talking about is possible”.

I’m proposing anti-desertifi cation structures made out of

the desert itself, sand-stopping devices made of sand: a poetic

proposal that simultaneously works in a sustainable

way with local materials and assets. Special emphasis has

been put on fi nding a solution that is high-tech in result

but low-tech in application and construction, with the economical

scenario being hard to pin down as this method is

virgin territory. It is recognized that poor people are highly

vulnerable to the effects of weather, as drought can cause

famine while good rains can cause drops in crop prices. The

architecture presented here could form a stable base from

which to fi ght back against both effects.

http://www.holcimfoundation.org/Portals/1/docs/A08EU/WinnerPoster_AME_A4_ng12_hires.pdf