Download unit 1 - natureboy

introduction
the
environment
unit 1
• sustainability
• what is it?
• why should you care?
• earth systems
• geosphere
• hydrosphere
• atmosphere
• biosphere
environmental science
science
• environment
• biotic and abiotic components
• ecology
• organization
• ecosystems
• communities
• assemblage of organisms
• community ecology
• study of interactions among organisms and abiotic factors
• inductive and deductive reasoning
• scientific method
• controlled experiments
• hypotheses, laws, theories
• what is science?
• guided by natural law
• testable
• conclusions are tentative
• falsifiable
• limitations of science
• nothing can be proven
• only human
• nature is complex
and how these interactions affect communities
matter
energy
• components of matter
• chemical elements
• molecules
• chemical compounds
characteristics
of matter
•
• physical change
• state change
• chemical change (reaction)
• rearrangement of atoms/
• what is energy?
• kinetic energy
• potential energy
• energy quality
• high vs. low
(-)
molecules
• law of conservation of matter
O
H
(+)
H
(+)
laws of thermodynamics
natural resources
• first law of thermodynamics
• law of the conservation of energy
• second law of thermodynamics
• “law of entropy” - no perpetual motion machine
• efficiency
• natural capital
• one of the major components of sustainability
• natural resources
• renewable vs. non-renewable
natural
services
•
unsustainable practices
unsustainable practices
• high-consumption / high-waste economies
• let’s not name names
• stimulate economic growth through:
• using more resources
• producing more goods and services
• converts many resources to waste, pollution, low-quality
• Energy Use
• doubled in the last 30 years
• will increase 60% by 2030
• mostly non-renewable resources
• gas, coal and oil
heat
INPUTS
(from environment)
SYSTEM throughputs
high-quality matter
high-waste
economy
high-quality energy
OUTPUTS
(into environment)
waste and pollution
low-quality energy
(heat)
copyright 2014. Cengage Learning, from Environmental Issues and Solutions
sustainability
sustainability
• working definitions
• “development that meets the needs of the present without
• three pillars of sustainability
• economy
• society
• environment
social
science principles of
•
compromising the ability of future generations to meet their
own needs” -Bruntland Commission, UN, 1987
• “living on the earth’s income rather than eroding its capital.”
-UK
sustainable development strategy
• “leave the world better than you found it, take no more than you
need, try not to harm life of the environment, make amends if
you do" -Paul Hawken, The Ecology of Commerce, 1993
sustainability
• economics
• full cost pricing
politics
•
• win-win solutions
• ethics
• responsibility to future
generations
sustaining life
ecosystems
• three scientific principles of sustainability
• solar energy
• chemical cycling
• biodiversity
• trophic structure
• food chains
• producers
• primary consumers
• secondary consumers
• tertiary consumers
• quaternary consumers
quaternary
consumers
tertiary
consumers
secondary
consumers
primary
consumers
producers
ecosystems
ecosystem dynamics
• trophic structure
• food webs
• biological magnification
• this is a big problem for
tertiary consumers
secondary
consumers
secondary
consumers
primary
consumers
primary
consumers
certain types of compounds
and elements
• DDT
• mercury
• PCBs
DDT concentration
increase of 10
million times
DDT in fish-eating
birds 25 ppm
DDT in
large fish
2 ppm
DDT in
small fish
0.5 ppm
DDT in
zooplankton
0.04 ppm
producers
DDT in water
0.000003 ppm
ecosystem dynamics
hydrological cycle
• ecosystem
• energy flow
• energy enters ecosystem through producers
• primary production
• resource cycling
10 kcal
• can be expressed as biomass
• ecosystems differ in biomass
tertiary
consumers
100 kcal
• flow of energy in food chain
• represented as pyramid
secondary
consumers
• chemical cycling
• constantly recycled
1000 kcal
primary
consumers
10,000 kcal
producers
sunlight
1,000,000 kcal
chemical cycling
carbon cycle
• general model for chemical cycling
• abiotic reservoirs
• producers extract chemicals from
• carbon dioxide cycles globally
• combustion
abiotic reservoirs
• decomposers return nutrients to
abiotic reservoirs
• local and global
• scale is different for different
nutrients
consumers
CO2 in atmosphere
producers
combustion
aerobic
respiration
photosynthesis
decomposers
higher level
consumers
nutrients
available to
producers
producers
primary
consumers
wood,
fossil
fuels
abiotic
reservoirs
animal bodies
decomposers
producers
detritus
leaf litter
phosphorus cycle
nitrogen cycle
• phosphate
• nitrogen
• most common gas in atmosphere
cycling
• no atmospheric
component
• very long term
N2 in atmosphere
plant
uplifting of
rock
weathering of
rock
phosphates in
rock
phosphates in
solution
animals
plants
runoff
denitrifying
bacteria
detritus
phosphates in
soil
(inorganic)
NO3- in
soil
phosphate sediment
(precipitation)
detritus
nitrogen-fixing
bacteria
bacteria
nitrifying
bacteria
rock
animal
ammonifying bacteria
decomposers
discussion questions
• what would happen to an ecosystem and to humans if:
• soil bacteria were lost?
• all producers were killed through loss of soil fertility?
• top level predators were removed from an ecosystem?
• what do we do about big predators?
• a shift to sustainable societies... unrealistic?
• Fermi paradox...
• what should we focus on?
• food?
• transportation?
• home energy?
• resource use?
NH4+ in soil