Scientists have proved that the world was covered with trees a few centuries ago. With the passage of time and increase in population, people started cutting down the trees and constructing buildings, homes, factories, etc., that brought a drastic change in the world climate. Due to the depletion of trees, lethal viruses and diseases have spread in different areas of the world. Trees are the best source of creating a balance in the environment. They provide oxygen, absorb carbon dioxide (CO2) and maintain the humidity in the air. They protect watershed which supply 75 percent of freshwater.

The authorities concerned and health departments should take serious steps and build nurseries so as to protect forests and everyone should grow more and more trees in their surroundings because trees are directly proportional to our health and inversely proportional to bad atmosphere.

TAYYABA ALI,

Karachi, May 30.