1. Impact of human activities on forest
• Clearing and burning of the forests for
agriculture,cattle rearing and timber extraction.
• Clear cutting and conversion of forest land in hilly
areas for agriculture,plantation and housing.
• Forests affected by acid deposition originating
from industries.
• Pesticides spraying to control insects in forest
plantation leads to poisoning all the way up the
food chain and unintended loss of species
2. Deforestation
• Clear-cutting of forests causes
erosion, flooding, and changes
in weather patterns.
• The slash-and-burn method of
clearing tropical rain forests for
agriculture increases
atmospheric CO2, which
contributes to the greenhouse
effect.
• Because most of the nutrients
in a tropical rain forest are
stored in the vegetation,
burning the forest destroys the
nutrients.
• As a result, the soil of some rain forests can support agriculture for
only one or two years.
3. Desertification
• Overgrazing and
developing of
grasslands that border
deserts transform the
grasslands into
deserts.
• As a result,
agricultural output
decreases, or habitats
available to native
species are lost.
4. India lost wetlands
• Wetlands and Watersheds are controlled by
interactions among chemical, physical, and
biological factors
• These interactions are controlled in two ways
– Human interactions
– Natural events and processes
5. India lost wetlands
• More than half of the original 110 million
acres of India wetlands have been lost
• These wetlands were destroyed in a variety of
ways due to human activities
– Mining - Waste disposal
– Agriculture - Mosquito control
– Urbanization - Industrial processes
– Construction - Draining
7. Stress on water-resources
• Less than 3% of the world’s water is
fresh – the rest is seawater and
undrinkable.
• Of this 3% over 2.5% is frozen, locked
up in Antarctica, the Arctic and glaciers,
and not available to man.
• Thus humanity must rely on this 0.5%
for all of man’s and ecosystem’s fresh
water needs.
