GREEN HOUSE EFFECT
As you know, living things are able to survive on earth only because the earth's climate is suitably warm. This is possible because the earth's atmosphere traps the sun's heat on the surface of the planet. If this trapping had not occurred over the past billions of years, plants and animals would not have evolved, as the earth would have remained a frozen planet. This is known as the Greenhouse Effect.

Due to the increase in carbon dioxide and other greenhouse gases in the environment, the earth is gradually becoming warmer and warmer. This warming can have huge and terrible effects on all of us: it can lead to unseasonal rains, flash floods, prolonged droughts and extremes of temperature in the summer (more hot) and winter (more cold). The ice-caps on the tops of mountains and the ice continents can melt, leading to even more problems for humans as well as all living things on earth.

Now imagine a world with millions of more trees than what we have at present. In such a world, most of the extra carbon dioxide would get absorbed by the trees, which need this gas for making food for the entire planet. At the same time, globally, more trees would mean better rains, cooler climates, and decreased use of air-conditioners and refrigerators. This would reduce the other greenhouse gases as well, leading to reversal of global warming. What a wonderful thing to happen!

 Examples of usefulness of trees:

Have you eaten an apple? A mango? Then you will know what I mean when I say that trees provide food. Other fruits like jackfruit, coconut and figs also grow on trees.

Most of the furniture in any house is made from wood. In mountainous regions, even the walls are made from logs of trees. In cold areas, where people need to heat their homes, wood from trees is used for heating.

Many medicines are derived from trees. These include medicines for fever, malaria and heart-diseases.

By absorbing the extra carbon dioxide and releasing oxygen, trees help make the environment clean and more suitable to live in. Forested areas are pleasantly cool, get better rainfall and have cleaner air.

Many trees are grown especially for their products, such as the rubber tree, which gives us rubber that is so useful to us. Nowadays, a lot of rubber is made synthetically in factories..

Trees are tall plants with hard and thick stems (trunks). The main trunks of large trees like the mango and the banyan bear many branches, which further divide into smaller branches. Leaves grow on these branches. Branching causes the tree to spread out wide on all sides.

Trees are Nature's wonders and a great gift to mankind as well as to all those who depend on them. While some dependants stay on the trees, others come to them to rest or to feed. Still others use them to raise their offspring. Humans have used almost any and every tree to their benefit.

It is very sad that the same humans are destroying trees all over the world in the name of "development". This can be to create factories, new townships, wider roads, railways, entertainment centres and so on. They do not realise that they are making a big mistake.

How trees are useful:

Trees are useful to us in many ways.

1. Food: Trees give us food such as fruits. These provide us with excellent nourishment.
2. Wood: The wood from some trees such as teak, walnut, rosewood and oak is used to make furniture. Wood from other trees is used as fuel for cooking and for warming houses.
3. Paper: Paper is made from wood.
4. Medicines: Many trees are the source of useful modern medicines.
5. Shelter: The canopy of leaves and branches gives us shelter.
6. Climate: Trees provide cool shade. Many trees, for example, in a forest, can make the climate pleasant and the air clean.
7. Rain: Forested areas get better rainfall compared to areas with no tree cover.
8. Oxygen: When trees respire, they release oxygen that all animals need for their survival.