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Activities that are Damaging our Earth and Environment

              Some of the human activities, which cause damage to the environment are over-exploitation of resources, pollution,
              deforestation, mining, destruction of natural habitats, construction, etc. Let us now discuss how some of these
              activities are damaging our earth and environment.
                 • Over-exploitation: This results when  harvesting of resources exceeds their  reproduction  or replenishment.
                It means that when we exploit the species faster than the natural populations can recover, then it may result
                in extinction of the species, thus affecting directly or indirectly the ecological cycle and our environment. For
                example, removal of wild medicinal plants, excessive grazing of pastures by animals, destruction of forests, and
                water aquifers, overfishing and over hunting, results in over-exploitation of forests and natural habitats.
                 • Mining: Mines are dug below the earth's surface to get ores. The ores are then refined to extract the valuable
                elements, such as metals, gems, minerals, etc. Some of the environmental impacts of mining include erosion,
                formation of sinkholes,  loss  of biodiversity, and contamination of soil,  groundwater and surface water by
                chemicals from the mining processes.

                 • Deforestation: It is the clearance of a forest or stand of trees where the land is converted to a non-forest use,
                such as agriculture and construction of houses. It results in loss of habitat for many plants and animals living in
                the forest. It may also lead to extinction of plant and animal species.

                 • Pollution: This word is derived from the Latin  word "polluere" meaning "to soil"  or "defile (contaminate)".
                Pollution is caused by pollutants, which may be solid, liquid, or gaseous in nature. Pollution is the effect of
                undesirable  changes in our surroundings that  have harmful effects on plants, animals, and  human beings.
                Pollutants are produced due to human activity, which have a detrimental effect on our environment.
                For example, factories consume a lot of water and electricity and release harmful chemicals in air, land, and
                water, thus contaminating the atmosphere. Water pollution caused by factories and other industries can be the
                most serious problem. They also pollute the air through fossil fuel emissions. These emissions include carbon
                dioxide, methane, and nitrous oxide, which are harmful to living beings.
              Pollutants are of two types:

                        Pollutants that can decompose                      Pollutants that cannot decompose


               Pollutants that  break down  into simpler, harmless  Pollutants which cannot be broken down  into simpler
               substances naturally (by the action of moisture and  and harmless substances are called non-biodegradable
               bacteria) are called biodegradable pollutants.    pollutants. The harmful effect caused by these pollutants
                                                                 will be there for hundreds of years.


               Examples: vegetable  waste, sewage  waste, paper,  Examples: plastics, insecticides, pesticides, chemicals like
               wood, cattle dung, agricultural waste from organic  mercury or lead, aluminium, glass, etc.
               farms, etc.

              Some of the other factors responsible for polluting the environment are as follows:
                 • Exhaust fumes released from vehicles pollutes the air.
                 • Excessive use of chemicals in agriculture (like insecticides and fertilisers) affect the alkalinity of the soil or the soil
                pH. It adversely affects the health of microorganisms and other organisms in the soil.
                 • Plastic waste like bottles, bags, etc., thrown on land and sea pollutes the water and destroys the flora and fauna.
                 • Dangerous gases (chlorofluorocarbons or CFCs, methane, carbon dioxide, etc.) released into the air.

              The various types of pollution are summarised in Table.





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