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?