SciDev.Net

Daniel Nepstad

Woods Hole Research Center

For five years, Daniel Nepstad and his team have been monitoring a very special corner of the Amazon rainforest.

In the largest experiment of its kind, they suspended 5,600 large plastic panels between one and four metres above the ground. As a result, a one-hectare plot is deprived of 80 per cent of rainfall, mimicking the conditions of a prolonged and severe drought.

In this article in Science, Erik Stokstad, describes Nepstad's unprecedented experiment, and its emerging results.

The good news, says Stokstad, is that the rainforest has remarkable tricks for dealing with low levels of rainfall.

For instance, the team found that trees push some roots deep into the ground and redirect water to shallower roots. Some trees also take in rainwater through their leaves.

The bad news, however, is that after four years the trees had been pushed to their limits and began to die.

With the trees dying, more sunlight reached the ground, drying the fallen leaves and greatly increasing the risk of fire.

Although the experiment is a "worst-case scenario", researchers believe it will help make predictions of the effects of climate change.

Link to full article in Science

Thousands of panels prevent rain from reaching the forest floor