Title: BIOLOGY 157: LIFE SCIENCE: AN ENVIRONMENTAL APPROACH (Systems
1BIOLOGY 157 LIFE SCIENCE AN ENVIRONMENTAL
APPROACH (Systems Ecosystems Modeling
Environmental Crisis)
2Systems and Planetary Organization
- System
- an interconnected complex of parts and processes
characterized by many cause-effect pathways
3Subdividing our Planetary System (I)
- Environment - the influences / forces /
conditions that surround an organism - Biotic vs. Abiotic
- Macroenvironment vs. Microenvironment
- Habitat - physical place where an organism or a
community lives - Macrohabitat vs. Microhabitat
4Subdividing our Planetary System (II)
- Atmosphere - the gaseous envelope around the
earth - Hydrosphere - all the water on the earth
- Lithosphere - the earths crust
- Pedosphere - on land, the surface part of the
lithosphere that has been modified by organisms
( the soil!) - Biosphere - the life layer, a hybrid region
consisting of those portions of the atmosphere,
hydrosphere and lithosphere that can support life
in an active form
5Subdividing our Planetary System (III)
6Subdividing our Planetary System (IV) Layers of
the Atmosphere
JET STREAM
7Subdividing our Planetary System (V)
- Biogeographic Realms - large areas (on land)
characterized by their flora and fauna - Biomes - an area (on land) whose biota is
controlled by (and is in balance with) the
climate and is distinguished by the dominance of
certain plants and animals(?? Can you name some
biomes ??) - Ecosystems - a unit composed of the biota and the
environment of a particular area(?? How many
ecosystems on the earth ??)
8Biogeographic Realms
9Biomes
10Environmental Problems vs.Root Causes
- PROBLEMS
- Global Warming
- Soil Erosion
- Desertification
- Air Pollution
- ROOT CAUSES
- Overpopulation
- Overconsumption
- Inefficiency
- Greed
11Eco Ethics (I)
- FRONTIER SOCIETY ETHIC
- ( Planetary Management Worldview)
- Anthropocentric
- Low Synergy
- -------------------------------------------
- -------------------------------------------
- The earth has unlimited resources.
- When resources are depleted in
- one area, just move to another
- area.
- The value of ones life is
- measured by the accumulation of
- material things
- SUSTAINABLE SOCIETY ETHIC
- ( Earth-Wisdom Worldview, Stewardship Ethic ?)
- Ecocentric / Biocentric
- High Synergy
- ----------------------------------------------
- ----------------------------------------------
- The earth has finite resources.
- We must prevent depletion by
- recycling and developing renewable
- resources.
- The value of ones life is more than
- just the sum of ones material
- wealth
12Eco Ethics (II)
- Economics is everything. It can
- all be boiled down to the cost of
- materials, energy and labor.
- Humans are not a part of
- nature. We are above nature.
- Nature is there for us to use
- and conquer.
- Human activities are expected
- to produce waste and it must
- be tolerated.
- New technology and new laws
- will solve our problems the
- majority can leave the
- The TRUE COST must include
- those things on the left AND also
- take into account the costs to the
- ecosystem and our health.
- We are a part of nature, and
- as such are subject to all of its
- rules.
- We are a part of nature. We
- must work with and within it.
- Waste is not to be tolerated or
- excused. All things should be
- recycled, reused, etc.
- While these things may help,
- we must all be involved in the
- solution of problems.
13Tragedy Of The Commons (I)
- Garrett Hardin
- The concept comes from the concept of common
lands in medieval England. - Is this idea coming back?
14Tragedy Of The Commons (II)
15Environmental Crisis ???
- The environmental crisis is real and it is VERY
complex. - Why is it so complex?
- the ecosystem itself is very complex
- many environmental problems
- numerous root causes
- problems and / or root causes often interact
- problems and / or root causes often transcend
political boundaries - viable solutions may not be available AND even
when available people may disagree on what, if
anything, is to be done or how to best go about
doing something
16Solving Environmental Problems
- must identify the major factors involved
- must decide on a mode of action
- must be committed to the solution
- must allocate the necessary resources
17Models / Modeling
- When investigating something (e.g. as in an
attempt to solve some type of problem) one
usually acquires a large amount of data. To try
to make some sense from the many components to
our problem we usually must construct some type
of MODEL. - DEFINITION - A Model is a physical or abstract
representation of the structure of a real system. - Some models may be quite simple while others may
be quite complex. - Models do NOT have to be mathematical but most
will need to be if they are to be of any real use.
18Examples Of Models (I)
- The generalized equations shown below are
examples from chemistry of very simple models. - A B ? C
- A B ?? C D
19Examples Of Models (II)
20Examples Of Models (III)
21Examples Of Models (IV)
22Examples Of Models (V)(Text, chapter 15)
23Parts Of A Model
- No matter how complex a model might appear,
there are, at most, three main components. - Variable ( systems variable)a number
representing the state of a particular component
in the model - Transfer Functiona number representing the flow
or exchange between compartments (between
variables) of a model. - Forcing Functiona number representing the
magnitude of some particular thing which
affects a system but is NOT affected back by the
system (may be present or absent).
24Feedback Loops In A System
- The parts of a model (variables, etc.) are
interconnected in various ways and usually have
effects on each other. They form pathways. Some
of these become FEEDBACK LOOPS. These loops can
be - NEGATIVEtends to keep things the same (at or
near the set point) - POSITIVEmoves things away from the set point
25Building A Model For Population Growth (I)
- Factors which could account for increase /
decrease in population size - 1) BIRTH RATE (a measure of fertility)the number
of births is affected by the number of people
present nutritional status (famine or plenty of
food) degree of medical technology as it might
relate to treating infertility or to providing
means of birth control - 2) SURVIVABILITYmedical advances which allow for
more people to live to reproductive maturity and
/ or to just live longer - 3) FOOD AVAILABILITYagricultural productivity,
distribution networks, income
26Building A Model For Population Growth (II)
- 4) SOCIETAL INFLUENCESReligion, Pride,
Nationalism, Political Views, Economics, etc. can
influence whether or not large or small families
are "in". - 5) RESOURCE AVAILABILITYResources can affect the
ability to develop and support technology or to
trade for technology and / or food necessary to
support the population. - 6) ENVIRONMENTIncluding disasters such as
droughts, floods, plagues, crop failure from
pests, war, pollution, etc. - all can affect the
ability to support a larger population
27Building A Model For Population Growth (III)
- Now, think for a minute how you would go about
connecting these. Remember some may connect to
quite a few. Then think about the magnitude (the
size or degree) of the effect that each would
have. Remember, we might have to add a few more
factors to this in order to make it a reasonably
'good' model.
28HISTORY LEADING TO ENVIRONMENTAL PROBLEMS
- To look at the development of the environmental
problem we might find it advantageous to look at
our 'roots'. That is to say we should look at
the evolution of our species and the development
of various major societal periods in the recent
history of Humans.
29HUMAN preHISTORY
30LUCY SKELETON
31RECENT EVOLUTIONARY HISTORY LEADING TO MODERN
HUMANS
- Dryopithecus (25mya) (Dawn Ape)
- Australopithecus (4-5mya)
- Homo habilis (2.5mya 1st humans
'Lucy') - Homo erectus (1.5mya)
- Homo sapiens (0.2 mya) (
200,000 ya) - (Cromagnon or
'modern humans,
about 40,000ya) - In the last 40,000 years (or even a bit longer)
it has been much more cultural and technological
changes rather than physical (or mental)
evolution that has accounted for the changes we
see in humans and their societies.
32HUMAN 'SOCIETAL' SYSTEMS (I)
- 1) Hunter-Gatherer Societypopulations more or
less NOMADIC more than 10,000 years ago
minimal impact due to small population size
minimal possessions, minimal resource use, thus
also providing for minimal impact slow pop.
growth rate - 2) Agricultural Societypopulations sedentary
started about 10,000 years ago - Subsistencefed your own family villages small,
impacts a bitlarger than H-G but still generally
minimal - Surplus (starting approx. 5,000 years
ago)allowed for or resulted in city formation,
resource movement (depletion - pollution),
changes in ideas, specialization, crafts, etc.
33HUMAN 'SOCIETAL' SYSTEMS (II)
- 3) Industrial Society
- a) EARLY --- 1760's to WWII
- b) LATE --- Post WWII
- The use of resources, pollution, dislocations,
population growth, etc. accelerates with each
stage and it is not an arithmetic progression,
but rather it is generally a logarithmic
progression.
34IMPACTS OF SOCIETIES
35TO SOLVE OUR PROBLEMS
- To solve our environmental problems (and possibly
other types of problems as well) we need to - 1) adopt a high synergy sustainable society ethic
- 2) control population size
- 3) use resources wisely (reduce amounts required
by using only where and when necessary and
by using only the amounts really necessary) - 4) reuse and recycle
- 5) use renewable resources whenever possible
(e.g. - solar energy instead of coal and oil)
36ADDITIONAL things from chapter 15 for YOU to
investigate
- 1) What does the EPA do?
- 2) What is Adaptive Management?
- 3) Compare and Contrast Environmental
Literacy and Environmental Policy - 4) BEFORE THE NEXT CLASS Google Wikipedia
for the terms wicked problem and
precautionary principle. What
relationships might these have to the
information in chapter 15?