"Quena Raymi" is a very special festival held once a year in the Peruvian Andes.
It's a tree-planting ceremony -- attended by over 200 men, women and children from various
villages in the area.
Once the festivities are over, they begin their hike up the mountain -- carrying shovels
and other tools, and provisions with them ... ((00:36)) PLUS infants and the saplings
-- even the llamas come along.
Their two-hour trek takes them to an altitude of over four thousand meters above sea-level.
They follow anicent paths once used by their ancestors.
The Incas lived in harmony with their environment.
For today's population, the idea is to give back what they have taken from nature.
The past few centuries have seen the area almost completely deforested, with no effort
to replenish the devastated woodlands.
These people are the first generation to recognize that something has to change.
Hermogenes, one of the village leaders, is here with his family.
"It's hard to dig holes in the ground here.
You might dislodge rocks -- you can never rule out accidents.
You have to be extremely careful.
"There are no trees left here -- and no firewood to gather.
So I'm glad that we're planting new trees.
My friends and neighbors have all come along to help.
Constantino Aucca is the man behind the project.
He set up an NGO called the "Association for Andean Ecosystems" -- or ECOAN -- in 2001.
He and his team want to plant 25 thousand saplings today.
They have to work quickly so that the roots won't dry out.
"If there's no vegetation or trees, the water will flow straight from the mountain down
into the valley, and cause landslides, before it continues on to the sea.
The new trees we're planting will absorb the moisture that nature gives to us -- mist and
rain.
The trees are the ONLY way we have of storing the water."
The tropical glaciers are the most important source of water in the Andes.
But global warming is causing them to melt away at a growing pace.
Entire swathes of mountain terrain used to be covered with polylepis trees -- a species
only found in South America.
It's highly resilient, and can withstand extreme weather conditions.
At night, temperatures here can drop to minus 20 degrees Celsius -- in both the winter and
summer.
The trees at these high altitudes therefore grow very slowly.
Over the last 19 years, the biologists from the NGO have been observing changes in the
local climate.
"People who come here expect to see huge forests with tall trees blocking out the sun.
What they don't appreciate is that we're 4,400 meters above sea level.
In some places, the tree line is as low as 3,500 meters.
But here it's different."
More woodland means more liquid in the overall water cycle.
The hope is that eventually this would enable the glaciers to reverse their retreat.
"When there is precipitation, when it rains, the trees ensure that the water does not simply
disappear.
Instead, it is stored by the trees' roots and by the moss that grows everywhere.
Otherwise it would evaporate far more quickly especially when the sun's shining, and be
carried away by the wind."
The slower the water makes its way down from the mountains, the longer it remains available
in the villages in the valley -- all year round.
Normally this would be the wet season, but rainfall has decreased -- something the villagers
are all too aware of.
The reforestation project includes the tree nurseries managed by local people.
In Hermogenes' village, the saplings are nurtured for 12 months, until they're sturdy enough
to be planted.
Their survival rate has now reached almost 90 percent.
ECOAN pays the villagers money for the trees.
The association itself is funded by private donations.
Some of the tree nursuries are now getting their own greenhouses, in order to provide
better protection for the plants.
And that also means new job opportunities.
This kind of work is hard to get, so it's a sound opportunity for us.
Not just for me as a technical specialist but also for my younger colleagues.
Logistically they need a lot of people.
And that also applies to the tree-planting enterprise, which involves villagers from
many local communities.
They're committed to the project -- even if its fruits will only be enjoyed by the generations
to come.