On the Yucatan Penisula, jungle fires fed by debris from last year's Hurricane Gilbert have damaged vegetation for hundreds of miles.

It also damages crops, trees and other vegetation.

A five-year study in Canada has found that road salt, a toxic substance, can damage waterways, soil, vegetation, fish, birds and some wildlife without harming people.

However, the chemicals are not in widespread use because they damage vegetation and contaminate water supplies.

They may damage fences, water sources, and vegetation (by overgrazing or introducing seeds of invasive plants).

Another example is of goats competing with cattle in Australia, or goats that damage trees and vegetation in environmentally-stressed regions of Africa.

"There is noise pollution, air pollution, and studies show they damage vegetation and may harm wildlife."

Ozone is helpful by absorbing the fiercer part of the ultraviolet radiation of the sun, but at ground level it damages materials and vegetation.

The amount needed to melt several inches of ice and keep it melted, he said, would be enough to damage soil and vegetation.

This led to, in some circumstances, overgrazing which damages natural and semi-natural vegetation.