Transcript An Introduction to Sustainability

An Introduction to Sustainability
An Introduction to Sustainability
“Unless someone like you cares a whole awful
lot, Nothing is going to get better. It's not.”
― Dr. Seuss, The Lorax
Key Concepts:
Are our present lifestyles sustainable?
(pause)
The Story of Stuff
The Story of Solutions
4
Why are our (developed countries – US, in
particular) lifestyle unsustainable?
Pause for discussion
Our lifestyle is unsustainable:
1. Over-exploitation of natural resources that
accompanied economic and demographic
growth
2. Market failure - Hidden environmental costs are
not reflected in market prices
3. Accelerating resource depletion, waste
generation, and environment pollution due to
shorten product lifecycles (technology
advances) and changing lifestyles since
industrial revolution
We Are Living Unsustainably
• Environmental destruction and degradation:
wasting, depleting, and degrading the earth’s
natural capital
– Happening at an accelerating rate
– Also called natural capital degradation
Humans Degrade Natural Capital
Fig. 1-9, p. 13
The Great Acceleration of Human Pressure on the Planet
The Great Acceleration of Human Pressure on the Planet
A Vision of a More Sustainable World
Sustainability is the overarching
theme of Environmental Science
Environmental Science
Environmental Systems
What do we learn in Environmental
Science?
How to deal with environmental problems
First of Four Spheres of Earth
• Biosphere refers to:
– All of the living parts of the separate ecosystems
of the Earth acting as one unit
– The parts that are organic and self-replicating
– Includes all of the plants and animals of the Earth
– Includes both living and dead organisms
Other Spheres of Earth
• Lithosphere – Above the core and mantle and
contains the top of the upper mantle and the crust
(which includes all of the soil & rocks)
• Hydrosphere – All of the liquid water on the Earth
and in the ground (groundwater), solid water in the
polar ice, permafrost, sea ice, and water vapor in the
atmosphere
• Atmosphere – Gaseous envelope that surrounds the
Earth as is comprised of multiple layers
Atmosphere
• Troposphere (layer closest to the Earth and
referred to as the boundary layer) contains
most of the Earth’s air (78% N2 & 21% O2) and
is where all weather is generated.
• Stratosphere contains the ozone layer which
absorbs ultraviolet radiation from the sun.
• Mesosphere is the coldest layer in the
atmosphere.
• Thermosphere which includes the:
– Ionosphere contains ions and is responsible for the
absorption of high energy photons from the sun.
– Exosphere is the outermost layer and merges with
outer space.
What Keeps Us Alive? Capital
Solar Energy: without the sun there
would be no life. (What is the difference
between direct and indirect solar energy?
Natural Capitals:
Air, water, soil etc.
Natural Capitals
How renewable a resource is
depends on the timescale of reference.
Solar
energy
Natural Capital = Natural Resources + Natural Services
Air
Renewable
energy (sun,
wind, water
flows)
Air purification
Climate control
UV protection
(ozone layer)
Life
(biodiversity)
Population
control
Water
Water purification
Pest
control
Waste treatment
Soil
Nonrenewab
le minerals
(iron, sand)
Soil renewal
Land
Food production
Nutrient
recycling
Nonrenewable
energy
(fossil fuels)
Natural resources
Natural services
Fig. 1-4, p. 9
Resources
 Perpetual: renewed
continuously on a
human scale.
 Renewable: can be
replenished fairly
quickly.
 Non-renewable:
exist only in fixed
quantities. (Once
they are gone, they
are gone.)
Fig. 1-5, p. 9
Ecosystems
• Ecosystem is a community of different species
interacting with each other and their nonliving environment.
ex. Great Lakes
Colorado River
The Adirondack Mountains
New York City
• Ecology is the study of the inter-connections
of nature.
Ecosystems
Living
Non-living
ABIOTIC COMPONENTS
BIOTIC COMPONENTS
Sunlight
Primary producers
Temperature
Herbivores
Precipitation
Carnivores
Water or moisture
Omnivores
Soil or water chemistry (e.g.,
P, NH4+)
Detritivores
etc.
etc.
All of these vary over space/time
Abiotic – chemical & physical
factors present in an ecosystem
Biotic – biological component–
contains all living organisms
Major Ecosystem Processes
The two major processes of any ecosystem are:
1) chemical cycling
2) one-way flows of energy (from the sun)
An ecosystem maintains overall stability by three chief
mechanisms:
1) controlling the rate of chemical or material cycling within the
system
2) controlling the rate of energy flow through the system
3) maintaining a diversity of species and food webs so that
system stability is not affected seriously by the loss of some food
web links and / or species.
Ecosystem problems can arise by:
1) Disruption of essential materials/nutrients cycles
a) changing the rate of cycling by material overloads or leaks
in the system
b) breaking of the cycle
c) introduction of human-made chemicals into the system, especially
those which have no natural decomposition chain
2) Disruption of energy flow(s)
a) entropy or heat build-up in the system by consumption of too much
energy by human society
b) changing properties and/or composition of the atmosphere leading
to an increase or decrease in the solar energy input or output
from the earth-atmosphere system
3) Disruption of the ecosystem by destruction of species diversity
and/or the food web
Ecologic-Environmental principles
• Your can’t get something for nothing, or there is not
such thing as a free lunch (first law of thermodynamics).
• If you think things are mixed up now just wait, or you
can’t even break even (second law of thermodynamic,
energy degradation “up and along” the food web ).
• Everything must go somewhere, or there is no thrown
away (law of conservation of matter)
• Everything is connected to everything, but how?
Ecologic-Environmental principles
• In most cases the greater the diversity of a system the
greater its stability.
• Nature frequently but not always “knows” best.
• Up to a point the bigger the better; beyond that point,
the bigger the worse (negative externalities, negative
“emergent properties,” threshold effects)
• Existence of non-linear and threshold effects
Nature has sustained itself for billions of years
…
It has done so using four principles:
1.
2.
3.
4.
Reliance on Solar Energy
Biodiversity
Chemical (Nutrient) Cycling
Population Control
What Are Four Principles of
Sustainability?
• Concept 1-1A Nature has sustained itself for
billions of years by using solar energy,
biodiversity, nutrient cycling, and population
control.
• Concept 1-1B Our lives and economies depend
on energy from the sun and on natural
resources and natural services (natural
capital) provided by the earth.
Nature’s Survival Strategies Follow
Four Principles of Sustainability
1. Reliance on solar energy
– The sun provides warmth and fuels
photosynthesis
We rely on solar energy
Reliance on Solar Energy: The Sun alone
provides all the energy for the planet
Nature’s Survival Strategies Follow
Four Principles of Sustainability
2. Biodiversity
– Astounding variety and adaptability of natural
systems and species
Biodiversity: The astounding variety of life
forms, the genes they contain, and the natural
services they provide have given countless
ways to adapt to the environmental changes
Diversity Makes a System Stronger
Diversity allows
natural systems to
function since every
player has a
particular role. When
one player drops out
or is unable to fulfill
its role AND if there is
no other player
around to step in,
system function is
compromised.
Nature’s Survival Strategies Follow
Four Principles of Sustainability
3. Chemical cycling
– Circulation of chemicals from the environment to
organisms and then back to the environment
– Also called nutrient cycling
Nutrient Cycling: Chemicals that plants
and animals need to survive and reproduce
are recycled by natural processes.
Nutrient Cycling
Fig. 1-5, p. 10
Nutrient Cycling
Fig. 1-5, p. 10
Nature’s Survival Strategies Follow
Four Principles of Sustainability
4. Population Control:
– Competition and limited resources puts limits on
how much any population on Earth can grow.
Four Scientific Principles of
Sustainability: Copy Nature