2. • Reduction or loss of plant and animal species is
called Biodiversity depletion.
• The cause for biodiversity depletion may be man
made or natural.
• Natural causes include floods, earthquakes,
landslides, diseases etc.
• Man made causes are called Anthropocentric
causes. Some of the anthropocentric causes for
biodiversity depletion are as follows:
3. Urbanization: It refers to the process of
increased concentration of human
population in large cities. Increased human
population has put a great strain on
agricultural land and forest. Clearing of
forests and conversion of agricultural lands
for human habituation has a direct impact
on biodiversity as it destroys natural
habitat eliminating important plant and
animal species.
4.
5. Expansion of Agriculture: It refers to
large scale expansion of land surface for
crop production. To meet the food
demands of increasing human population,
natural habitats like forest and grasslands
are encroached and converted into
agricultural fields causing loss of natural
habitat.
6.
7. Deforestation: It refers to destruction or
removal of forests. As a part of
development to meet the demands of
human society, forests are regularly
cleared for human settlement, grazing
grounds, industries, agriculture,
construction of dams and roads etc.
Deforestation make huge land area barren
and unproductive resulting in biodiversity
depletion.
8.
9. Pollution: Any undesirable change in the natural
qualities of environment due to addition of
physical, chemical and biological factors is called
as pollution. The factors that contribute to pollution
are called pollutants. Pollution of air, water and soil
has a direct or indirect impact on the human,
animal and plant life. Pollutants like pesticides,
radioactive material, SO2, oxides of nitrogen,
heavy metals, chlorofluorocarbon,
chlorofluoromethane, silt and sewage etc., have
become a cause for elimination many sensitive life
forms.
10.
11.
12.
13.
14. Acidification of Soil and Water: It refers to
decrease in pH of soil and water. Generally
most of the soil and water are found to be
slightly alkaline or neutral. Human activities
like excessive use of nitrogen based chemical
fertilizers, acid rain due to SO2 and Oxides of
Nitrogen pollution cause acidification of soil
and water. Many plant and animal species are
sensitive to acidic condition and such species
are eliminated from the habitat causing
biodiversity depletion.
15.
16. Mining Activity: Mining is the process of
excavating non-renewable resources like coal
and minerals from the earth. Surface mining
or Open pit mining activity has direct impact
on the fauna and flora of the area and also
causes environmental pollution. Also to store
mined material and to dump the residue left
after extracting the ore requires huge land
area. Thus mining has a worst impact on the
environment and it biodiversity.
17.
18. Desertification: Desertification is the
process leading to desert formation.
Deforestation and overgrazing brings
about marked changes in the climate of
the area like changes in rainfall,
temperature and wind velocity causing soil
erosion and increased dust particles in the
atmosphere. This causes desertification.
As a result critical habitat for fauna and
flora will be lost.
19.
20. Loss of Soil fertility: Top soil is fertile soil as it is
rich in humus and mineral. It supports rich soil
biodiversity. Soil erosion, intensive agriculture,
continuous monocrop cultivation, disposal of solid
wastes, pesticides, indiscriminate use of chemical
fertilizers are some of the common causes for loss
of soil fertility. The process of removal of top fertile
soil is called soil erosion. Deforestation, over
grazing of animals, unscientific agricultural
practices, landslides, heavy wind and floods are
the common causes of soil erosion. These
changes can eliminate many plants species and
microorganisms.
21.
22. COME LETS ALL JOIN
HANDS AND TRY TO
PROTECT THE EARTH
FROM DEPLETION OF
BIODIVERSITY AND SAVE
THE RESOURSES FOR OUR
YOUNGER GENERATIONS
TO COME.
