2. Introduction to PART 4
What is a sustainable development?
What do we think about sustainability ?
Which resources are in danger of
exhausting? Why?
May our society go on consuming
resources indefinitely?
Which global problems have only a
solution with sustainability ?
7. A Town Without Water (p.132)
Where does water flowing form our taps at
our high school come from?
8.
Which are the energy sources at our
school? So, where does energy to feed all
devices (lights, computers, heating, etc.)
come from?
9. Energetic Resources:
These are goods extracted from nature to
be used as energy sources
Some are renewable (wind) and others not
renewable (oil, fossil fuels)
There is endosomatic energy (food) and
exosomatic energy (lifestyle, biomass)
The use of every kind of energy is quite
different from one country to another (see
Table on p. 134)
10. The Future of Energy Use:
We hope of renewable energies because
sooner or later non renewable will run out
Nuclear fission energy (not renewable)
Hydrogen as a fuel (renewable)
Hydroelectric energy (r)
Tidal energy (r)
Nuclear fusion energy (r)
Others: wind, photovoltaic, geothermal (r)
http://lasfuentesdeenergia.blogspot.com/
11. Green Gold: Biofuels
We may consider it as
renewable because
production is fast (time
for growing and
harvesting crops) and it
is exploited at a similar
rate to which the
resource is generated
12. Biofuels
Monoculture
of sugar cane
and corn not to be used as a
food resource replaces food
plants growing, like some cereals
which are very important for
feeding. Massive transformation
of that kind of growing has been
controversial, specially in SouthAmerica , because there is the
risk of provoking food problems
in wide regions
13. Water: An Essential Resource
The water we use comes from superficial
waters (reservoirs) or aquifers (wells)
The way we use it:
Farming use (flood and drip irrigation)
Industrial use (cooling, paper, steal, plastic)
Domestic use (hygiene, washing, toilet, gardens)
Energetic use (hydroelectric energy)
Ludic use (fountains, swimming-pools,
waterparks, golf courses)
15.
Due to solar energy and the force of gravity
water flows through the hydrosphere, but not all
fresh water is suitable to be used by humans
The need for water may cause overexploitation
of aquifers in zones where it scarcely rains
(Mediterranean shore) and provoke well salinity
Several human activities generate residues and
cause contamination
Microorganisms in aquatic systems purify water.
Wastewater treatments (sewage) eliminate
contaminants and give back water quality
17. Solutions to Lack of Water:
Reducing consumption
Increasing efficiency of
installations
Desalination of seawater
Inter-basin transfer from drainage
basins with water surplus
19. Calculations with our Water Bill
67000 L/90 days = 744,4 L per day
744 L/5 people = 148,8 L person and day
(Barcelona 122 L/day, with some savings it
could oscillate between 70 and 100 L daily)
153,27 €/67000 L = 0,002 € each L (100 L
cost almost 20 cents). Bottled water is
much more expensive (50 c/L)
20. Calculations with our Water Bill
We add VAT and other city taxes: 7,31 €+
30,49 € = 37,8 € taxes. 37,8·100/153,27 =
24,66 % taxes
2 million people using 148,8 L per person
and day, during 365 days would need:
2·106·148,8·365 = 108624·106 L per year.
To convert into hm3 we divide per 109. The
final result is a yearly consume of 108,6
hm3 water
21. Forest Resources
Forests cover 1/3 of emerged lands and
are inhabited by most of identified species
There are near 2 million different species,
and maybe even more, that is what we call
as BIODIVERSITY
Between 50 and el 90 % of species live at
rainforests (6 % of emerged lands)
22.
Thick forests play a major role in
atmosphere regulation
They incorporate CO2 and release O2
during photosynthesis
Forests produce humidity and influence
local climate: they make it milder and
diminish oscillations due to near zones
lacking in woods
23. Resources from the Forests
Raw material to produce: furniture, building
materials, paper, food, energy, chemicals (against
cancer)...
Some years ago CHARCOAL was the main
source of primary energy
During the Industrial Revolution it was replaced
by COAL (from a mineral origin)
But there are still many countries whose
resources are in part based in BIOMASS from the
forests (firewood from logs and branches and
charcoal)
More than a half of wood is used to produce
FUEL, a basic combustible in many poor
countries
25. Forests Exploitation
Economic growing and demographic progression provoke
an excessive exploitation of forest resources
Many poor countries pay their debt to the rich ones with
natural resources (wood, precious minerals...)
In Brazil rainforest is transformed into pasture to fatten up
herd
In Madagascar sugar cane monoculture replaces rainforest
In Malaysia part of the rainforest is exploited to get more
wood
At the island of Kalimantan (Indonesia) the natural habitat
of orang-utan is being destroyed and substituted by palm
trees to produce palm oil
http://teknociencia.wordpress.com/2008/12/31/pocos-motivos-para-laesperanza-en-la-isla-de-borneo/
27. Exploitation of resources must be
SUSTAINABLE and they should never be
extracted to a rate higher than they take to
regenerate
At this very moment there are lots of
places all along the planet where forests
supposedly RENEWABLE are exploited
so much intensely that they are becoming
NON RENEWABLE resources
A forest may take decades or even
centuries to regenerate
28. Reforestations
Lots of forests have been substituted by
harvesting and pasturing zones
Some countries have increased or maintained
forest surfaces too
REFORESTACIONS have been made using fast
growing trees which are not original (pine,
eucalyptus...)
Reforestation with plants that are not typical
from the habitat involves some problems:
diminishing original species, loss of original
forest, spreading of illnesses, loss of diversity,
drought, risk of forest fires
29. Paper and Fast Wood
Using digital supports, reusing paper
(using the back side to print rough draft),
sensitizing people
Foreign species play the role of other
original species until they can eliminate
them. Eucalyptus have caused the
disappearing of lots of original woods at
the Cantabrian cornice and Galicia and it
is also a species prone to spread fire
30. Ground as a Resource
It is an interaction zone between living
beings and environmental elements
(rocks, air, water) and the place where
plant nutrients are generated and retained
Ground is a dynamic natural system that
has been formed by rock changes due to
atmospheric agents and living
beings action
31.
It takes a lot of years for a ground to be
formed, however it is easily eroded
away
It is a main resource because it is the
substrate from where primary producers
get part of the mineral matter they need to
live
There live decomposer
microorganisms that transform organic
matter into inorganic nutrients for plant
feeding
Ground has a farming and cattle use .
Production of growing and pastures
depends on ground quality and fertility
32. The Loss of Ground
Intensive farming (heavy machinery,
monoculture) provokes impoverishment and
needs the increasing use of fertilizers
(phosphates and nitrates) that will pollute
groundwater
The number of heads of livestock per
hectare of pasture must respect the
ground features. An excess of them may
cause degradation (erosion,
compactness...)
33.
The most important loss of ground is due
to water erosion . Rain drags ground
materials
Mediterranean climate (dry summers,
intense rains in fall) and the geological
conditions of our countryside become a
very serious problem in our land
Alzira floods in 1982
34.
35. Deforestation and Desertification
Forest degradation is connected with loss of
ground, since vegetal covering contributes to
conservancy and stability
Cause of deforestation: abusive logging in
territories for several uses (mining, pasturing,
growing, roads...)
Another cause of deforestation: forest fire . The
loss of thick forest decreases CO2 fixation and
increases the greenhouse effect
36.
Forest zones decrease ground eroding .
Vegetation intercepts one fraction of the
falling water, it reduces impact speed and
diminishes the eroding power of
precipitations. It also decreases run-off
and contributes to diminish hydric erosion
of the ground
Roots make ground eroding difficult, they
keep it more compact, and accumulated
organic matter (plant litter, leaves in
process of decomposition) and humus
protect it from erosion
37.
Deforestation and loss of ground entail
desert advance, what is known as
desertification
Arid lands (1/3 of the planet) are
extremely vulnerable to overexploitation
and inappropriate use of land
According to FAO at the beginning of 21st
century more than 250 million people
are now affected by desertification and
some 1000 million in more than 100
countries will be at risk the next years
Damaging of habitats and loss of
biodiversity
38.
39. Global Seed Vault :
A Noah’s Ark for Plants
They would be difficult to reforest, since
survival of species cannot be split
up from the presence of other living
beings and environment (species do
not live isolated). According to the degree
of damage in ecosystems, it could not be
easily reforested
40. Global Seed Vault :
A Noah’s Ark for Plants
Natural climate conditions in Svalbard
archipelago are ideal, specially low
temperatures, what permits to keep seeds
without germinating and in good conditions
The existence of a seed bank allows
preserving the genetic heritage of the
Earth and its biodiversity , and one never
knows if we could need to use this
biological potential in future situations
41. Section of the Global Seed Vault at Svalbard Islands (Norway)
42. To Learn More
WEBS where the Global Seed Vault project
is explained:
http://es.wikipedia.org/wiki/B
%C3%B3veda_Global_de_Semillas_de_Sva
lbard
http://www.croptrust.org/main/arctic.php?
itemid=211
http://en.wikipedia.org/wiki/Svalbard_Globa
l_Seed_Vault
