This document discusses finding sustainable sources of energy and food for humanity. It notes that fossil fuels are finite and have environmental impacts. Renewable energy sources like solar, wind and hydro are introduced as more sustainable alternatives. Sustainable agriculture techniques that conserve soil and water are also described. Achieving global food security requires addressing issues like population growth, land degradation, and equitable food distribution. Creating a sustainable society involves meeting present needs without compromising the future through efficient energy and resource use, reducing pollution, and stabilizing population growth.

1. LAST LECTURE Envi 201
FINDING ENERGY , FOOD FOR
HUMANITY AND SUSTAINABLE
SOCIETIES

2. • The fuels we use to run cars, ships, planes and
factories, to produce electricity are natural
resources
• Most of the energy we use comes from a group
called fossil fuels
• These are remains of ancient organisms that
changed into coal, oil or natural gas
• Fossil fuels central to life in modern societies

3. Yet there are two problems with fossil fuels
1. The supply of fossil fuels is limited
2. Obtaining and using them has environmental
consequences
In the 21stC, societies will continue to explore
alternatives to fossil fuels but will also focus on
developing more efficient ways to use these fuels

4. Energy
• Energy is defined as capacity to do work
• Sun is the pry source of energy the standard unit
of energy is Joule in SI units
• Energy utilization is an economic development
which does not take into account the ill effects or
damage to the environ.
• Energy is renewable, non-renewable and
sustainable

5. Renewable energy sources
• These include- wind power, wave power, Ocean
Thermal Exchange Capacity{OTEC}
• Solar power, hydro-power, fuel cells{biomass fuels eg
alcohol form, sugar, methane from organic waste or
charcoal from trees and biodiesel
• Characteristics of renewable energies is : energy
sources are continually available but require good
management
• Others such as solar and wind are available for the
forseable future without any human intervention

6. Non-renewable types of energy
• These include fossils fuels- coal, gas and their
derivatives eg petrol and diesel
• Non-renewable are finite in supply as their rate
of formation is so low
Sustainable energy
• Sustainable is term applied to nuclear power
• The supply is not exactly renewable but will last
for so long because of great electricity is
produced from small amount of radioactive
material

7. • The 3 sources of energy above have very different
characteristics0 meaning no ideal energy source
• The future will most likely be a mix of sources
with increase in emphasis on the renewable
Environmental Impacts of Energy Sources
• Non-renewable Energy Sources affects the
environ as follows[fossil fuels{coal, oil,gas, peat,
lignite etc}

8. • Habitat modification and destruction, pollution
etc due to extraction of fuel by mining, drilling,
quarrying and excavation
• Visual and environ impacts from spoil and solid
wastes
• Pollutes surrounding water, air and land by
waste water and leachates from mining, drilling
and excavation and gas leaks from pipes
• Secondary pollution thro’ purification or
modification

9. Advantages of hydropower :
• Long life
• Renewable
• Low operating and maintenance cost
• Absence of inflationary pressures as in fuels
Drawbacks to environ
• Large areas of forest and agric land require, much
water required, rivers required for other uses
• Silting of reservoirs-reduce life of hydroelectric
power installations
• Displacing people
• Provoking seismic hence earthquakes

10. Solar energy
• Discontinuous nature, cloudy etc
Biomass Energy
• Deforestation in many industrializing nations
• Smoke- can cause respiratory ailments
• Biogas is sometimes stinky
• Wind power
• Bird kills, noise effect on TV reception etc.

11. • Energy use in industrialized verses unindustrialized
countries{ read and write notes}
Promoting efficiency of electricity
• Turn off lights appliances when not in use
• Promote energy efficient appliances eg fluorescent
lights
• Put water heaters at aps and reduce hot water use
• Better insulation in homes can reduce needs for
heating
• Design houses with many insulated windows
reduces need for lighting

12. Promoting efficiency of transportation
• Mass transit- reduce need for individual transport
uses buses and matatus.
• Energy efficient cars
• Good roads
• Reducing urban sprawl
• Industry- co-generation{heat from one process
can be captured and used in another process} or
used to produce electricity

13. Individuals
• Turn down water taps, heaters
• Cover pots while cooking
• Use low –watt light bulbs
• By energy efficient appliances
• Carpool, walk, use matatu
• Use fuel efficient cars

14. Finding Food for Humanity
• Food is regarded as a fundamental right
• Allowing people to starve is usually viewed as
inhuman and unjust
• World food day is usually on 16th oct every year
• Highlights the need to ensure that all people have
physical and economic access to enough,
nutritious, safe food to lead healthy and active
lives

15. • Our food comes from agriculture, animal
husbandry and fishing that is 76% from
croplands, 17% from range lands 7% marine and
fresh water-fisheries
• What is food security?
• What causes food insecurity?
• What is the importance of green revolution?
• How can food distribution problems and
drought lead to famine?

16. Food Security
• Food security is a that situation when all
people at all times have physical and
economic access to enough safe and
nutritious food to meet their dietary needs
and food preferences for an active and healthy
lifestyle{World Food Summit 1996}

17. To be food secure means
1. Food must be available- in amount, quality
globally, nationally and locally. Climate disasters,
war, civil unrest, pop size and growth, agric
practices, environment, social status and trade
affect food temporary or for along time
2. Food affordable{each person should have
access}- sometimes food prices rise hence richer
pple access it and poor people may have difficult
in obtaining sufficient safe and nutritious food
without assistance

18. 3.Food is utilized{the food utilized must fulfill
nutritional requirements}
• At the house level. Sufficient and varied food
needs to be prepared safely so that people can
grow and develop normally, meet their energy
needs and avoid disease
Effects of Food Insecurity
• Children die- due to malnutrition and other
dietary deficiencies
• 17-40% of world pop is malnourished or
undernourished hence shorter life expectancy

19. Causes of food security
• Pop growth ,Degradation of agricultural land
• Poor agricultural practices, Loss of genetic
diversity
• Poverty, Poor health, Water shortage
• Lack of gender equity, Natural disaster
• Conflicts, urbanization, trade imbalance, biofuel
climate change and use of genetically Modified
Seed vaiety

20. How to achieve food security
• Population control, farming more land
• Reducing farmland control conversion
• Making exiting land more productive
Class activity
• Compare subsistence and industrialized agric
• What are long term problems associated with
industrialized agric? Eg soil erosion, water
logging and salinization ,desertification, mass
production of hybrid varieties, nutrient
depletion, water and air pollution
• Compare Organic fertilizers use and synthetic

21. Sustainable Agriculture
• The world finds itself in cross roads
• Caught betwn industrial agric methods which are
highly productive but not sustainable
• The search on agric that is highly productive and
beneficial to nature that is sustainable agric
• The FAO[Food and Agriculture Organization of
UN} defines sustainable agric as the one which
conserves, land, water and plant and genetic
resources, does not degrade the environ and is
economically viable and socially acceptable

22. • Techniques and Actions that can be taken to
bring us closer to sustainable Agriculture
• Reducing Soil Erosion through: minimum tillage,
contour farming, strip cropping, terracing,
shelterbelts{rows of trees planted along he
perimeter of cropland and along stream banks}
• Preventing desertification- thro’ green walls of
vegetation protect forests, better management
of livestock to prevent overgrazing

23. -more organic farming, small fields, crop rotation
• Saving irrigated cropland from waterlogging,
salinization and overdrawing of water thro’
• -use water more efficiently, monitor field
moisture so that water is only applied where
and when it is needed, line irrigation ditches or
use pipes to transport water, water crops at
night with sprinklers that spray downward,
improve amount of organic material in the soil,
use drip irrigation techniques

24. Sustainable crop breeding thro’
• Protecting the earth’s genetic diversity, breed for
crops that do not require large amounts of
chemicals or energy inputs, allow local farmers to
have autonomy over their seeds and selective
breeding, more research independent of agro-
business industries, with overall good for
humanity in mind
• Alternative foods – native edible plants that are
not grown crops, animals that have no been
domesticated- these can contribute greatly to
human nutrition and crop diversity and have not
been exploited

25. • Aquaculture-improved fish farming methods to
supplement protein source
• Eating lower on food chain- plants and plant
produce. Vegetable diets than a meat based
diets
• Better storage and transport- control pests and
diseases sustainably, improve in transits and
storage eg refrigeration of food, reliance on
local arms for produce and less on world market

26. • Trade related issues-International trade policies to
improve flow of food across national borders from
those with surplus to places of deficit,, stop dumping
underpriced foodstuffs onto markets of
underdeveloped countries, this undermines prices an
forces farmers to adopt unsustainable practices to
compete
• Organic Farming-producing food naturally, avoid use
of synthetic chemicals-use crop rotation, green
manure, composts, biological pest control and
mechanical cultivation to maintain soil and pest
control-zero impact on the environment, protect the
earth resources and produce safe, healthy food

27. • NB: World food security is currently in danger
• There is a challenge in feeding an ever
increasing pop without destroying the soil and
water resources upon which food production
depends
• Pop growth should be halted
• Stop reliance on fossil fuels, stop depleting soil

28. SUSTAINBLE SOCIETIES
• Currently the human system is not sustainable
• The rate of human pop growth is out of control
• The resources we depend on for daily living eg
agricultural land and development eg fossil fuels
are being depleted
• The general health of the planet has been
severely affected by disruption of natural
processes and depletion of biodiversity

29. • How can human system be more sustainable
and adaptable?
1. Sustainable development- this is development
that meets the needs of the present without
compromising the ability of future generations
to meet their own needs{the World
Commission on Environment and
Development, Brundtland Commission 1987}
2. Sustainable society- is a society that interacts
with its environment in ways that cause little
other than short-storm change and maintain
the integrity and interactions of the biosphere

30. • This means when people use earth’s resources
eg forests, water, minerals, wildlife etc they
must take account not only how much of these
resources they are using but also what
processes they use to get these resources and
who has access to these resources
• The following questions should be asked and
answered: are enough resources going to be left
for our future generations to use?
• Will the environment be left as we know today?

31. • The primary objective of sustainable
development is to :
• reduce absolute poverty of the world’s poor
thro providing lasting and secure livelihoods
that minimize resource depletion,
environmental degradation, cultural disruption
and social instability.
• Also considers the equity betwn countries and
continens,races and closes, gender and ages
• It includes social and economic development

32. • It is a process which leads to better quality of life while
reducing the impact on the environment
• To accomplish sustainable development a number of
areas have to be organized
I. Improving energy efficiency
II. Saving forests
III. Safeguarding biodiversity
IV. Adopting water resources
V. Managing coastal zones and ocean fisheries
VI. Arresting pollution
VII. Planning cities better
VIII.Accomplishing a second green revolution
IX. Stabilizing world pop and stopping environmentally
destructive subsidies

33. Components of sustainable Society
1. Sustainable use of energy
2. Sustainable use of atmosphere
3. Maintenance of soil fertility
4. Sustainable use of water
5. Sustainable use of nonfuel mineral resources
6. Sustainable use of Biological resources
7. Maintenance of biodiversity
8. Limitation of pop to the carrying capacity of the
environment
9. Sustainable economic policies, accounting of
environmental damage and true measure of quality of
life
10. Political stability and equality

34. Conclusion
• Humans still rely on the environment for life
• It provides the air, shelter, water and food
• We must understand how to keep the
environment alive in order to also to keep
ourselves alive for a high quality of life for all of
God’s creatures
• We must learn how biosphere functions to
achieve the goals of a sustainable society
• Research must continuously be done on
understanding interactions, rates and cycles. If
not unsustainable societies will be