Soil
It is the mixture of minerals, organic matter, gases, liquids, and the countless organisms that together
support life on Earth.
In terms of soil texture, soil type usually refers to the different sizes of mineral particles in a particular
sample. Soil is made up in part of finely ground rock particles, grouped according to size as sand and
silt in addition to clay, organic material such as decomposed plant matter.
POLLUTION                                                      Cause : Vehicle or manufacturing
                                                                exhaust, Forest fires, volcanic eruptions,
It is the introduction of contaminants into the                 dry soil erosion, and other natural sources,
natural environment that cause adverse                          Building construction or demolition
change.
                                                            Water pollution
Pollutants
                                                               When some foreign particle, organic,
It is the substance or agent of pollution. It is
                                                                inorganic or biological impurities are
harmful to nature.
                                                                added to the water so that it becomes unfit
Primary Pollutants are injected into the                        for use is known as water pollution.
atmosphere directly. e.g. smoke, carbon                        Major Water pollutants: Point Sources:
monoxide, nitric oxide , sulphur dioxide, dust,                 Sewerage system and industrial effluents
ash, salt particles, etc.                                       etc. Diffused sources: Agriculture. Mining
                                                                and construction etc.
Secondary pollutants are formed by chemical                    Cause : Increased sediment from soil
reaction between the primary pollutants and                     erosion, Improper waste disposal and
constituents of the environment (i.e. those                     littering, Leaching of soil pollution into
which are already present in the environment).                  water supplies, Organic material decay in
e.g. smog, ozone, sulphur trioxide, nitrogen                    water supplies
dioxide, etc.
                                                            Soil pollution
Air pollution
                                                               When the productivity of the soil reduces
     When some foreign particles enters the air                due to the presence of pollutants in it is
      and deteriorate its quality is known as air               known as soil pollution. Man has polluted
      pollution. These particles can be produced                the soil by the excess use of pesticides.
      naturally or man made. Dust storms,                      Major soil pollutants: Pesticides,
      Bacteria and gases of volcanic eruptions                  fungicides and herbicides
      are examples of natural’s sources of                     Cause : Hazardous waste and sewage
      pollutants. Gases released from the                       spills, Non-sustainable farming practices,
      automobile and the chimneys are the                       such as the heavy use of inorganic
      example of man made pollutants.                           pesticides, Strip mining, deforestation, and
     Major Air pollutants: Carbon monoxide                     other destructive practices, Household
      (CO), Ozone (O3), Nitrogen dioxide                        dumping and littering
      (NO2), Sulphur dioxide (SO2), etc.
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