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  • This is a man-made forest.

  • It can spread over acres and acres of area,

  • or it could fit in a small space --

  • as small as your house garden.

  • Each of these forests is just two years old.

  • I have a forest in the backyard of my own house.

  • It attracts a lot of biodiversity.

  • (Bird call)

  • I wake up to this every morning,

  • like a Disney princess.

  • (Laughter)

  • I am an entrepreneur

  • who facilitates the making of these forests professionally.

  • We have helped factories,

  • farms,

  • schools,

  • homes,

  • resorts,

  • apartment buildings,

  • public parks

  • and even a zoo

  • to have one of such forests.

  • A forest is not an isolated piece of land where animals live together.

  • A forest can be an integral part of our urban existence.

  • A forest, for me,

  • is a place so dense with trees that you just can't walk into it.

  • It doesn't matter how big or small they are.

  • Most of the world we live in today was forest.

  • This was before human intervention.

  • Then we built up our cities on those forests,

  • like São Paulo,

  • forgetting that we belong to nature as well,

  • as much as 8.4 million other species on the planet.

  • Our habitat stopped being our natural habitat.

  • But not anymore for some of us.

  • A few others and I today make these forests professionally --

  • anywhere and everywhere.

  • I'm an industrial engineer.

  • I specialize in making cars.

  • In my previous job at Toyota,

  • I learned how to convert natural resources into products.

  • To give you an example,

  • we would drip the sap out of a rubber tree,

  • convert it into raw rubber

  • and make a tire out of it -- the product.

  • But these products can never become a natural resource again.

  • We separate the elements from nature

  • and convert them into an irreversible state.

  • That's industrial production.

  • Nature, on the other hand, works in a totally opposite way.

  • The natural system produces by bringing elements together,

  • atom by atom.

  • All the natural products become a natural resource again.

  • This is something which I learned

  • when I made a forest in the backyard of my own house.

  • And this was the first time I worked with nature,

  • rather than against it.

  • Since then,

  • we have made 75 such forests in 25 cities across the world.

  • Every time we work at a new place,

  • we find that every single element needed to make a forest

  • is available right around us.

  • All we have to do is to bring these elements together

  • and let nature take over.

  • To make a forest we start with soil.

  • We touch, feel and even taste it

  • to identify what properties it lacks.

  • If the soil is made up of small particles it becomes compact --

  • so compact, that water cannot seep in.

  • We mix some local biomass available around,

  • which can help soil become more porous.

  • Water can now seep in.

  • If the soil doesn't have the capacity to hold water,

  • we will mix some more biomass --

  • some water-absorbent material like peat or bagasse,

  • so soil can hold this water and it stays moist.

  • To grow, plants need water, sunlight and nutrition.

  • What if the soil doesn't have any nutrition in it?

  • We don't just add nutrition directly to the soil.

  • That would be the industrial way.

  • It goes against nature.

  • We instead add microorganisms to the soil.

  • They produce the nutrients in the soil naturally.

  • They feed on the biomass we have mixed in the soil,

  • so all they have to do is eat and multiply.

  • And as their number grows,

  • the soil starts breathing again.

  • It becomes alive.

  • We survey the native tree species of the place.

  • How do we decide what's native or not?

  • Well, whatever existed before human intervention is native.

  • That's the simple rule.

  • We survey a national park

  • to find the last remains of a natural forest.

  • We survey the sacred groves,

  • or sacred forests around old temples.

  • And if we don't find anything at all,

  • we go to museums

  • to see the seeds or wood of trees existing there a long time ago.

  • We research old paintings, poems and literature from the place,

  • to identify the tree species belonging there.

  • Once we know our trees,

  • we divide them in four different layers:

  • shrub layer, sub-tree layer, tree layer and canopy layer.

  • We fix the ratios of each layer,

  • and then we decide the percentage of each tree species in the mix.

  • If we are making a fruit forest,

  • we increase the percentage of fruit-bearing trees.

  • It could be a flowering forest,

  • a forest that attracts a lot of birds or bees,

  • or it could simply be a native, wild evergreen forest.

  • We collect the seeds and germinate saplings out of them.

  • We make sure that trees belonging to the same layer

  • are not planted next to each other,

  • or they will fight for the same vertical space when they grow tall.

  • We plant the saplings close to each other.

  • On the surface, we spread a thick layer of mulch,

  • so when it's hot outside the soil stays moist.

  • When it's cold,

  • frost formation happens only on the mulch,

  • so soil can still breathe while it's freezing outside.

  • The soil is very soft --

  • so soft, that roots can penetrate into it easily,

  • rapidly.

  • Initially, the forest doesn't seem like it's growing,

  • but it's growing under the surface.

  • In the first three months,

  • roots reach a depth of one meter.

  • These roots form a mesh,

  • tightly holding the soil.

  • Microbes and fungi live throughout this network of roots.

  • So if some nutrition is not available in the vicinity of a tree,

  • these microbes are going to get the nutrition to the tree.

  • Whenever it rains,

  • magically,

  • mushrooms appear overnight.

  • And this means the soil below has a healthy fungal network.

  • Once these roots are established,

  • forest starts growing on the surface.

  • As the forest grows we keep watering it --

  • for the next two to three years, we water the forest.

  • We want to keep all the water and soil nutrition only for our trees,

  • so we remove the weeds growing on the ground.

  • As this forest grows, it blocks the sunlight.

  • Eventually, the forest becomes so dense

  • that sunlight can't reach the ground anymore.

  • Weeds cannot grow now, because they need sunlight as well.

  • At this stage,

  • every single drop of water that falls into the forest

  • doesn't evaporate back into the atmosphere.

  • This dense forest condenses the moist air

  • and retains its moisture.

  • We gradually reduce and eventually stop watering the forest.

  • And even without watering,

  • the forest floor stays moist and sometimes even dark.

  • Now, when a single leaf falls on this forest floor,

  • it immediately starts decaying.

  • This decayed biomass forms humus,

  • which is food for the forest.

  • As the forest grows,

  • more leaves fall on the surface --

  • it means more humus is produced,

  • it means more food so the forest can grow still bigger.

  • And this forest keeps growing exponentially.

  • Once established,

  • these forests are going to regenerate themselves again and again --

  • probably forever.

  • In a natural forest like this,

  • no management is the best management.

  • It's a tiny jungle party.

  • (Laughter)

  • This forest grows as a collective.

  • If the same trees --

  • same species --

  • would have been planted independently,

  • it wouldn't grow so fast.

  • And this is how we create a 100-year-old forest

  • in just 10 years.

  • Thank you very much.

  • (Applause)

This is a man-made forest.

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B1 TED forest soil tree layer nutrition

【TED】Shubhendu Sharma: How to grow a forest in your backyard (How to grow a forest in your backyard | Shubhendu Sharma)

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    Josie Tan posted on 2017/05/26
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