IF one tree is felled in the jungle, it does not mean that a city will disappear under floodwaters the next morning. But if an area of jungle the size of six football fields is cleared every minute, it could well mean that our cities will one day be inundated. The jungle, among other things, retains water that has fallen as rain, preventing it from overflowing a wider area. Unfortunately, the jungle in this country is being cleared at an ala