9th Class Science Natural resources Air Pollutions

        Air Pollutions

Contamination of air by poisonous gases released by various means and many other chemicals is called air pollution. The main reason for air pollution is the rapid industrialization and urbanization. This rapid growth and development is reducing the area under the forest leading to the release of gases like sulphur dioxide, carbon dioxide, carbon monoxide, nitrogen oxide, hydrogen sulphide, lead oxide in the atmosphere. Many poisonous gases released by industries and factories, in the atmosphere. In today’s time the main reason for the air pollution is also the large number of vehicles on the roads. These air pollutants can cause respiratory problems, renal problems, high blood pressure, nervous problems and many other health hazards.

The large scale release of gases like sulphur dioxide in the atmosphere cause acid rain which makes the soil very acidic and hence affects the plants and animals. It also leads to the reduction in production of food grains due to loss, that is, of fertility of the soil. The air pollution cause two major ecological problems, green house effect and ozone layer depletion. The green house effect is due to the increase in the concentration of carbon dioxide, which leads to the heating up of the atmosphere and hence cause global warming. The other is the ozone layer, which is a thick blanket of \[{{O}_{3}}\] molecules called the isotopes of oxygen that protects us from the harmful ultraviolet radiation. These harmful ultraviolet radiation can cause skin cancer, immune deficiency, cataracts and damages the plants and forest.

The main region for the hole in the ozone layer is the release of CFC gases. The CFC gas consists of chlorine, fluorine, and carbon. Thus, if we have to protect our atmosphere we have to stop the use of harmful gases like CFC that

           Water

Water is considered to be a wonderful liquid and all the life forms on the earth is possible due to the water only. About 75% of the earth surface is covered with water, but the concentration of fresh water i.e. potable water is very less and is nearly 2.5%. This entire water bodies is called hydrosphere. The fresh water are found in river, ponds, lakes, glacier of mountains, and underground. Water is essential for the survival of life forms on the earth.

Water is considered to be essential because all the reaction that takes place within our body and within the cells occurs in the liquid medium only. The movement of substance from one part of the body to the another part cannot takes place in the form of solid molecule, it flows in the form of liquid, dissolved in water.

The ground water is the water which is found inside the earth surface. The level of ground water increases with the absorption of water by the surface, during rainy season. When rainfall takes place a portion of the rain water is absorbed by the surface. The rain water can also be harvested by other means, such as, by digging wells, percolation pits, building dams etc. The rain water harvesting is very useful to us for irrigation and many other purpose.

The contamination of water by some poisonous chemicals that makes it unfit for drinking and endangered other aquatic life form is called water pollution. The water pollution is of three types, inland water pollution, underground water pollution, and marine water pollution. The various sources of water pollution are given below:

The various sources of water pollutions are Petroleum oil, fertilizers, detergents, industrial wastes and sewages. There are many harmful effect of water pollution. The main disease which causes by the water pollution are: typhoid, cholera, dysentery, jaundice and hepatitis. It also disturbs the ecological balance and affects the life forms in water bodies and many other food chains. Large scale water pollution leads to the killing of aquatic life in sea and oceans. It reduces the oxygen content of water, which makes it difficult for the life forms to survive. It also leads to the killing of some of the useful microorganism that helps in purification of water by degrading the biological wastes.