Air Pollution Water pollution Land pollution Deforestation Acid Rain
Air Pollution
Air provides us the oxygen that we need for our survival. We inhale the oxygen and give out carbon dioxide, which is used up by plants to make their own food. Clean air is essential for our wellbeing; otherwise we would suffer from many lung and other diseases.
The development of industries and other human activities have caused great harm to the air around us. We burn fossil fuels such as oil, coal and natural gas to make electricity, metals and other products. Petrol is also used in our cars and motorbikes. Burning of these fuels emits poisonous gases into the air. Carbon dioxide released as a natural breathing process as well as through the fumes emitted by the vehicles also pollutes the air. Petrol engines release carbon monoxide, hydrocarbons, and oxides of nitrogen into the air in addition to carbon dioxide. We take in all these gases when we breathe, leading to many respiratory and heart diseases.
Water pollution
Water is an important element for the survival of all the living things. As we know water is one of the best solvents in the world. The flow of water carries away whatever material is put in it from one place to another. Usually many unwanted things such as sewage, industrial chemicals, pesticides, fertilisers and other pollutants are dumped into streams, rivers and the seas. The sewage discharge in the Ravi River has reduced its fish population. The Kabul River is polluted by the industry in Peshawer. Faisalabad discharges high levels of solid, metals, dyes, inorganic salts, and organic material into the municipal sewers without any treatment. Sometimes the polluted water from rivers is passed into the irrigation system, contaminating the crops as well. This is the cause of many stomach disorders, especially in children. When the contaminated water flows into the seas and rivers these pollutants are taken in by the marine life as well and ultimately transferred to humans when eaten.
Deforestation
Trees are the lungs of our land. They clean the air by releasing large amount of oxygen and taking away carbon dioxide. Their leaves provide food for animals and the wood is utilised for domestic and industrial use. More importantly they are used to make paper. However, the utilisation of wood is increasing at an alarming rate. Large tracts of forest are cut down so that the wood can be sold commercially. Consumption of fuelwood also takes place unchecked in Pakistan, as a large portion of the population relies on it for heat. Trees are the natural purifiers of air; they take in carbon dioxide and give out oxygen. Deforestation means that we are losing one of our major sources of oxygen and that the amount of carbon dioxide is increasing.
Shockwave File
Trees also regulate the flow of water and protect the soil from erosion. In hilly areas where the forests have been cut, landslides occur very often leading to a loss of life and property.
Acid Rain
Fossil fuels have sulphur and nitrogen in them. When burned they combine with oxygen to form sulphur dioxide and nitrous oxide. These combine with water droplets in the air to form sulphuric and nitric acids.
Sulphur+Oxygen ---------------Sulphur dioxide
Sulphur dioxide+Water---------------Sulpuric acid
Nitrogen oxide + Water---------------Nitric acid
These acids fall to the ground as acid rain, resulting in damage to soil, buildings, wild life, sea and other water reservoirs, machinery and human beings. This happens because as we all know acids are dangerous and even though acid rain is a dilute form of acids they are still harmful.
