Key Components For Sustainability(i) Natural capital

These are natural resources and natural services that keep us and other forms of life alive and support our human economies

o Natural resources: materials and energy in nature that are essential or useful to humans

o Natural services: processes in nature, e.g. purification of air and water and renewal of topsoil, which support life and human economies.

As long as we use natural resources and services in a sustainable fashion, natural capital can support the earth’s diversity of species

Fig. 1-4, p. 9

Natural capital: supported by solar capital

A natural service which is one of the key principles of sustainability

This important natural service recycles chemicals needed by organisms from the environment (mostly from soil and water) through those organisms and back to the environment

Nutrient Cycling

Fig. 1-5, P. 10

An important component of nutrient cycling is topsoil in which plants grow

Topsoil provides the nutrients that support plants, animals, and microorganisms living on land

Without nutrient cycling in topsoil, life as we know it could not exist

(ii) Human activities Human activities can degrade natural capital:-

(i) By using renewable resources faster than nature can restore them e.g.

Clearing mature forests much faster than they can grow back

eroding topsoil faster than nature can renew it

withdrawing groundwater that was stored for thousands of years faster than nature can replenish it

(ii) Overloading natural systems with pollution and wastes

e.g.

loading some rivers, lakes, and oceans with chemical and animal wastes faster than these bodies of water can cleanse themselves

Scientific solutions are needed for environmental sustainability

e.g. solutions to unstainable use of natural capital –forests, animals, pollution of rivers, etc.

(iii) Scientific solutions

Are we Living Sustainably or Unsustainably?

We are living unsustainably by wasting, depleting, and degrading the earth’s natural capital at an accelerating rate

This is referred to as environmental degradation or natural capital degradation

Countries differ in levels of unsustainability because as human population grows, more and more people seek to satisfy their needs and wants by using more resources

Economic growth is an increase in a nation’s output of goods and services.

Usually measured by the % of change in a country’s gross domestic product (GDP)

GDP is the annual market value of all goods and services produced by all businesses operating within a country.

Per capita GDP:- Changes in a country’s economic growth per person. Measured by the GDP divided by the total population at midyear

Economic development is an effort to use economic growth to improve living standards.

• Based average income per person, countries are classified as developed or less developed .

• More-developed countries (high average income PP): North America, Australia, New Zealand, Japan, most of Europe

The more developed countries contain 19% of the world’s population

They use about 88% of all resources

Produce about 75% of the world’s pollution and waste

• Less-developed countries: most countries in Africa, Asia, Latin America

81% of the world’s people live

Less developed countries are classified into two:

(i) middle-income, moderately-developed countries e.g. China, India, Brazil, Turkey, Thailand, and Mexico

(ii) low-income, least-developed countries e.g. the Congo, Haiti, Nigeria, and Nicaragua.

Fig. 1-9, p. 13

Natural Capital Degradation

Degradation of Normally Renewable Natural Resources due to population increase and resource use per person

Climate change

Shrinking forests

Air pollutionDecreased wildlife habitats

Species extinctionSoil erosion

Water pollution

Declining ocean fisheriesAquifer

depletion

Results of unsustainable living

Selected environmental problems

(i) Pollution

Pollution—any presence within the environment of a chemical or other agent such as noise or heat at a level that is harmful to the health, survival, or activities of humans or other organisms.

Types of pollution are air, water, soil, and food pollutants

Pollutants can enter the environment into two ways;

(i) Naturally e.g. from volcanic eruptions

(ii) Through human activities, e.g. burning of coal or gasoline, and the dumping of chemicals into rivers and oceans

Pollutants sourcesoPoint sources; are single, identifiable sources

E.g.

Smokestack of a coal-burning power or industrial plant

Exhaust pipe of an automobile

Discharges from a sewage treatment plant, a factory

Nairobi river, Kenya

E.g. Pesticides blown from the

land into the air,

Runoff of fertilizers, pesticides,

Trash from the land into streams and lakes

o It is much easier and cheaper to identify and control or prevent point source pollution than nonpoint sources

o Nonpoint sources; are dispersed and often difficult to identify

Types of pollutants

o Biodegradable pollutants- are harmful materials that natural processes can breakdown over time. E.g. human sewage and newspapers.

o Non-degradable pollutants-Harmful chemicals that natural processes cannot breakdown. E.g. toxic chemical elements such as Lead and mercury, plastics

Effects of Pollutants

(i) They can disrupt or degrade life-support systems for humans and other species

(ii) They can damage wildlife, human health, and property

(iii)They can create nuisances such as noise and unpleasant smells, tastes, and sights

Solutions to pollution

o Pollution prevention (input pollution control)

Reduces or eliminates production of pollutants

o Pollution cleanup (output pollution control)

Cleans up or dilutes pollutants after they have formed

Disadvantages of relying on pollution cleanup

(i) Temporary solution as long as population and consumption levels grow without corresponding improvements in pollution control technology.

E.g., Garbage collection in Nairobi.

(ii) Cleanup often removes a pollutant from one part of the environment only to cause pollution in another. E.g. garbage collection…

what next?

Burned- possibly causing air pollution and leaving toxic ash that must be put somewhere

Dumped on the land-possibly causing water pollution through runoff or seepage into groundwater

Buried- possibly causing soil and groundwater pollution

(iii) Once pollutants become dispersed into the environment, it is usually too expensive to reduce them to acceptable levels

There should be more emphasis on prevention because it works better and in the long run is cheaper than cleanup

(ii) Overexploitation of Shared Renewable Resources

Three types of property or resource rights

Private property- individuals or companies own the rights to land, minerals, or other resources

Common property- the rights to certain resources are held by large groups of individuals e.g. community/government land in Kenya

Open access renewable resources- owned by no one and available for use by anyone at little or no charge e.g. atmosphere, underground water supplies, and the open ocean and its marine life.

Many common-property and open-access renewable resources have been degraded.

This type of degradation is called the tragedy of the commons.

Reasons for degradation:-human attitude

(i) “If I do not use this resource, someone else will”.

(ii) “The little bit that I use or pollute is not enough to matter”

(iii) “it’s a renewable resource”

(iii) Ecological Footprint

Ecological footprint: the amount of biologically productive land and water (Biocapacity) needed to provide the people in a region with indefinite supply of renewable resources, and to absorb and recycle wastes and pollution

It is measured in global hectares

Per capital ecological footprint:The average ecological footprint of an individual in a given country or area

It includes amount of land and water needed to provide:-

oThe amount of building materials you use in your home and workplace

oThe amount of water you use in your home, workplace and garden

oThe fossil fuels (oil, coal, wood and natural gas) needed to:-

provide the power to run your home and workplace bring your food from all over the world power your vehicles and transport carry away and dispose of your waste

Ecological deficit: Occurs if a country (or the world’s) total ecological footprint is larger than its biological capacity to replenish its renewable resources and to absorb the resulting wastes and pollution

In such scenario, the country or world is living unsustainably by depleting its natural capital

Fig 1-13 Page 16: Humanity's Footprint (1961-2050)

No. of earths= Ratio between resource demand & Biocapacity

Demand = population times per capita consumption , Biocapacity = 1planet

So Where are We At?

Humanity’s ecological footprint exceeds by at least 30% the earth’s biological capacity to support life.

It now takes more than 1.2 years for the Earth to regenerate what we use in a single year

Population growth and increasing development and means that we are increasing our use of Earth’s carrying-capacity

Per capita consumption also influences ecological foot print

Developed countries have very large ecological foot prints compared to less developed countries due to high per capita consumption- influenced by wealth and advanced technology

Causes of increasing Ecological footprint

Comparative Per capita ecological foot print

• Wealth

• Technology

National Footprints In U.S. each person uses about 9.7

hectares/person

Worldwide average = 1.7 hectares/person

Therefore if everybody were to adopt the U.S. consumptive style, how many planets

would we need ???

(See Supplement 8, p. S40, for a map of countries that are either ecological debtors or ecological creditors).

Ecological Overshoot When humanity's ecological resource demands exceed what

nature can supply, we reach ecological overshoot/Ecological tipping point

A situation in which an natural system experiences a shift to a new state, with significant changes to biodiversity and the services to people it underpins

Potential tipping points;(i) Collapse of certain populations of fish due to overfishing

(ii) Premature extinction of many species due to overhunting or clearing their habitats

(iii) Long-term climate change due to burning coal and oil

(iv)Deforestation

(v) Loss of groundwater

Four Major causes of environmental problems

1. Population growth (group 1)

2. Wasteful and unsustainable resource use (group 2)

3. Poverty (group 3)

4. Failure to include the harmful environmental costs of goods and services in market prices (group 4)

Three Big Ideas on sustainable living

1. We could rely more on renewable energy from the sun, including indirect forms of solar energy such as wind and flowing water, to meet most of our heating and electricity needs.

2. We can protect biodiversity by preventing the degradation of the earth’s species, ecosystems, and natural processes, and by restoring areas we have degraded.

3. We can help to sustain the earth’s natural chemical cycles by reducing our production of wastes and pollution, not overloading natural systems with harmful chemicals, and not removing natural chemicals faster than those chemical cycles can replace them.