WORLD ENVIRONMENT

ENVIRONMENT

Forests are valuable for many reasons. The timber, foods and medicines that use ingredients from forests are worth billions of dollars every year. However, they are also extremely valuable to us in ways that are difficult to calculate in terms of money.

These children in the Philippines were made homeless and orphans by flash floods. This happened because the forests on surrounding hills had been cut down, increasing the amount of water flowing down hillsides.

FLOODS AND DROUGHT

Trees play an extremely important role in the control of floods and droughts. During torrential rains the leaves in the forest canopy break the fall of rain drops, reducing their impact on the soil and young plants below. The spaces in the soil made by tree roots then help the water to soak in. Forest work like huge sponges soaking up rainfall and releasing it slowly throughout the year into streams and topping up underground water supplies.

A PHILIPPINE DISASTER

In November 1991 flash floods raced down the hillsides above the coastal town of Ormoc in the Philippines. Within minutes the water rose to 4 m deep in the streets. Seven thousand people were drowned.

The tragedy was blamed on illegal logging, which had stripped the hills of the dense rain forest that once clothed them. Without the forests to absorb it, the torrential tropical rain raced down valleys, smashing houses

and bursting river banks. Thousands of illegally cut logs were swept down from the mountain sides, giving a clue to the cause of the disaster.
Ninety years ago 80 per cent of the Philippines was covered in forest. Now it has fewer trees per person than any other Southeast Asian country,

mostly because of illegal logging. 

India is a good example of how the cutting down of forests causes floods and droughts. About 60 million hectares of land in India are now vulnerable to flooding more than twice as much as 30 years ago. And in the Indian state of Uttar Pradesh alone where there has been heavy logging activity the number of villages that are short of water has risen from 17,000 to 70,000 in the last twenty years. 

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