Desertification is a complex
process involving multiple natural
and human-related causes. In
desertification, the productive
potential of arid and semi-arid
lands falls by 10% or more, and
topsoil is lost or degraded.
– Desertification results mainly
from a combination of natural
climate changes causing
prolonged drought and
unsustainable human activities,
including overgrazing and
Overgrazing on marginal lands (top) can
extend desert zones (lower)
Biodiversity is the degree
of variation of life forms
within a given species,
ecosystem, biome, or an
entire planet. Biodiversity is a
measure of the health of
ecosystems. Biodiversity is in
part a function of climate.
If anything in your dustbin
can be reused by
somebody else, recycled
or repaired it should not
Waste is Costly
The earth is a closed system. Matter
amoung keeps constance. There are
• Any nutrients and resources being
taken out of the system (and buried
in a landfill, or burnt) are resources
lost to us.
To produce one ton of paper, 100 tons of
water are used.
For every litre of beer, 10 litres of water
have been used in the fermenting process.
Producing one cellphone requires 75 kg of
A toothbrush requires 1,5 kg of resources
– coal, oil and water – for its production
Benefits of recycling
• reduces the amount of waste going into landfill sites,
• creates jobs and money for schools and organisations
• reduces pollution and litter;
• saves raw materials needed to make new products
• reduces the need to import expensive raw materials
Benefits of recycling
• slows down the use of the world’s non-renewable
(oil, coal and iron) and renewable resources
• reduces energy costs in manufacturing of containers,
• saves water (used in packaging and product
manufacture). Recycling paper uses 50% less water
than paper that is made from wood pulp.
1) Why can we say Nature is continuously recycling?
2) Which are the main points to be considered in human
impact on the environment?
3) Write five actions to make a contribution to solve global
4) Describe in your owm words, the human contribution to
5) Give three reason to practise the recycling that you can
do in your diary life
A particular slide catching your eye?
Clipping is a handy way to collect important slides you want to go back to later.