earth systems the environmentnatureboy.com/sust100/sus100module1fall2019.pdfthe environment unit 1...
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the environmentunit 1
introduction• earth systems
• geosphere• hydrosphere• atmosphere• biosphere
• anthrosphere• sustainability
• what is it?• why should you care?
sustainability• working definitions
• “development that meets the needs of the present without 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
“ways of knowing” • understanding the world
• empirical knowledge• ethical knowledge• intuition• anecdotal
• how do we find truth?• Art• Science• Music• Philosophy• Literature• Religion/Theology
Should we focus more on utilitarian value or intrinsic
value?
science• does science answer all questions?• what is science?
• guided by natural law• testable • conclusions are tentative• falsifiable
• scientific method• proof? (reducing uncertainty)
• controlled experiments• hypotheses, laws, theories• peer review
• observation• hypothesis• experimentation• interpretation• prediction
misunderstandings• language and science
• “theory”• false equivalencies
• trying to balance viewpoints?• is everything up for
debate?• vaccines• climate change• evolution• Antifa vs. Neo-nazis
Samuel Corum/Anadolu Agency via Getty Images
matter• components of matter
• chemical elements • molecules
• chemical compounds• characteristics of matter
• physical change • state change
• chemical change (reaction)• rearrangement of atoms/
molecules• law of conservation of
matterH H
O
(-)
(+) (+)
energy• what is energy?
• kinetic energy• potential energy• energy quality
• high vs. low
laws of thermodynamics• first law of thermodynamics
• law of the conservation of energy• second law of thermodynamics
• “law of entropy” - no perpetual motion machine• efficiency
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 heat
high-quality matter
high-quality energy
waste and pollution
low-quality energy (heat)
INPUTS SYSTEM throughputs OUTPUTS
high-waste economy
(from environment) (into environment)
copyright 2014. Cengage Learning, from Environmental Issues and Solutions
natural resources• natural capital
• one of the major components of sustainability• natural resources
• renewable vs. non-renewable• natural services
sustainability• three pillars of sustainability
• economy• society• environment
• how do we achieve sustainability?• economics
• full cost pricing• politics
• win-win solutions• ethics
• responsibility to future generations
sustaining life• three scientific principles of sustainability
• solar energy• chemical cycling• biodiversity
• trophic structure• food chains
• producers• primary consumers• secondary consumers• tertiary consumers• quaternary consumers
ecosystems
primary consumers
secondary consumers
tertiary consumers
quaternary consumers
producers
ecosystems• trophic structure
• food webs
primary consumers
primary consumers
tertiary consumers
secondary consumers
secondary consumers
producers
• biological magnification• this is a big problem for certain
types of compounds and elements
• DDT• mercury• PCBs
ecosystem dynamics
DDT in small fish 0.5 ppm
DDT in zooplankton
0.04 ppm
DDT in water 0.000003 ppm
DDT in large fish
2 ppm
DDT in fish-eating birds 25 ppm
DDT concentration increase of 10 million times
ecosystem dynamics• ecosystem
• energy flow• energy enters ecosystem through producers
• primary production• can be expressed as biomass• ecosystems differ in biomass
• flow of energy in food chain• represented as pyramid
• chemical cycling• constantly recycled
primary consumers
tertiary consumers
secondary consumers
producers
10 kcal
100 kcal
1000 kcal
10,000 kcal
1,000,000 kcalsunlight
hydrological cycle• resource cycling
chemical cycling• general model for chemical
cycling• abiotic reservoirs
• producers extract chemicals from abiotic reservoirs
• decomposers return nutrients to abiotic reservoirs
• local and global• scale is different for different
nutrients
consumers
producers
decomposers
nutrients available to producers
abiotic reservoirs
carbon cycle• carbon dioxide cycles globally
• combustion
higher level consumers
producers
primary consumers
photosynthesisaerobic respirationcombustion
wood, fossil fuels
decomposers
producersproducersproducersproducersproducersproducers
detritus
leaf litteranimal bodies
CO2 in atmosphere
phosphorus cycle• phosphate cycling
• no atmospheric component• very long term
plants
phosphates in rock animals
detritus
decomposers
phosphates in soil
(inorganic)
phosphate sediment (precipitation)
phosphates in solution
rock
uplifting of rock
weathering of rock
runoff
nitrogen cycle• nitrogen
• most common gas in atmosphereN2 in atmosphere
plant animal
nitrogen-fixing bacteria
detritus
ammonifying bacteria
bacteria
NH4+ in soil
nitrifying bacteria
denitrifying bacteria
NO3- in soil
discussion questions• what are some examples of false equivalencies?• How do you think humans fit into ecosystems?:
• What 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?