Human Impact on Environment
Human Impact on Environment GEOG 113
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Date Created: 10/03/15
LECTURE OUTLINE GEOGRAPHY 113 HUMAN IMPACT ON THE ENVIRONMENT I INTRODUCTION A Course objectives 1 content goal we will ask How are humans altering the world they live in a this is an example of a generic type of question in science 1 V 2 V 3 V science is the source of formal knowledge and then of technology as well as we apply the knowledge represents an ordinary human activityinquiry curiosity a V primitive people asked amp answered questions about the sun food water animals health b you ask about the world when you get dressed to go outside choose a way home try to make a new computer program work science is an organized version of this activity a shared standards of evidence and proof b common intellectual tools physics from Newton eg the question in this course is specific to aspect of the world environmental science 1 ecosystems 2 human population 3 resources 4 pollution 2 intellectual goals of the course a b this is not a course for geography or environmental studies majors almost all students in this room are here to satisfy their BA science requirements skills amp perspectives of the course are meant to be general of value for anyone 1 2 recognize elegance power coherence of broad organizing principles and of mechanical explanation seeing how different problems share important characteristics that help us understand them trust your own ability to observe the world see problems and seek solution 394nyone Who conducts an argument by appealing toAuthority is not using his Intelligence he is just using his memory i eonardo Stop this day and night With me and you shall possess the origin of all poems You shall possess the good of the earth and sun there are millions of suns iefL B D Course outline Geography 113 Spring 2008 You shall no longer take things at second or third hand nor look through the eyes of the dead nor feed on the spectres In books You shall not look through my eyes either nor take things from me You shall listen to all sides and filter them from your sell Walt Whitman 3 know some facts about an interesting aspect of the world 3 topic is concrete to us allour enviromnent a we relate to it with ordinary activities food family travel purchases b and also with extraordinary activities catastrophes dramatic degradation health imp acts Approach will be analytic amp synthetic rather than merely descriptive 1 di 39erences are this a ask how the parts of this system work together synthesis b don t ask what s the biggest river in Nebraska description 2 longterm value of waysofthinking exceeds any facts you would retain you can look up the facts in the encyclopedia what you need to know in short term for the course isn39t the facts 3 stuff vs things dichotomy you can look up all that stuff remember the important things you will do badly on the first exam if you know lots of stuffyou only need to know one number for example and it is 7 details later 4 if you know the principles you can reconstruct the speci cs a the Reagan principle b the meandering of streams as an exampleifyou ve seen one meander you ve seen them all Organization of the course see syllabus 1 lecture readings for material 2 the purpose of the outlines 3 quizzes amp three examsWhy so many 4 helpoffice hours Environment what does it mean 1 we use it to describe a set of human concerns about a cleanliness litter smog b health diseasecausing or toxic pollutants b nature wildlife natural ecosystems 2 to most people environment usually refers to the human environment and what is wrong with it although we should think of wellness as a goal not just responses to pathologies 3 most people are interested in the environment in large part because of their affection for it it is a source of beauty peace food recreation complexity resources we should avoid the danger of seeing only bad Course outline Geography 113 Spring 2008 3 4 environment also a concept from biology means surrounding a d organisms inseparable from environment they are part of it not within it Ecosystem is the common term for situation of organism within its environment includes 1 abiotic nonliving elements light heat minerals 2 biotic elements other organisms eX prey and predators every organism changes its environment 1 removes food 2 adds wastes may make other changes eX trees make shade amp soil 5 The human environment is a biological environment a b except humans are much more powerful through technology interaction of technology amp nature underlies most environmental problems however we cannot suspend the laws of physics amp principles of biology E geography and environmental science 1 What is geography This section is from the National Geography Standards from NCGE amp NGS aimed for K 12 students There are 18 standards or goals which are grouped into six categories themes called quotThe six essential elements of geographyquot These six elements and the standards included under each of them are as follows a The World in Spatial Terms Geography studies the relationships between people places and environments by mapping information about them into a spatial context The geographically informed person knows and understands Places and Regions The identities and lives of individuals and peoples are rooted in particular places and in those human constructs called regions Physical Systems Physical processes shape Earth39s surface and interact with plant and animal life to create sustain and modify ecosystems Human Systems People are central to geography in that human activities help shape Earth39s surface human settlements and structures are part of Earth39s surface and humans compete for control of Earth39s surface Environment and Society The physical environment is modified by human activities largely as a consequence of the ways in which human societies value and use Earth39s natural resources and human activities are also influenced by Earth39s physical features and processes The Uses of Geography Knowledge of geography enables people to develop an understanding of the relationships between people places and environments overtime that is of Earth as it was is and might be 2 what does it have to do with environmental science Course outline Geography 113 Spring 2008 optimism and the study of the environment 1 it is a problem for many people to study only the bad parts of the environmental situation 2 we should remember that people care about these issues because of their affection for and connections to the natural world 3 focusing on how problems can be solved is useful in the short and the long run II SYSTEMS amp CYCLES Mhg etc we stl ll have meantnl ms Meg we elm5d wagdag 50 wry aren39t Meg gene A general thee51 sta 10 help as understand the LMCld and lts part5 System as a concept any part of the universe that we can think of as a unit is a system 1 value of the concept a helps us understand how parts of the environment interact with oneanother b we also can understand properties of only that part 2 underlying principle conservation of matter and energy First Law of Thermodynamics a the first law energy or matter is neither created nor destroyed b everything that went into the system is either still in there or has come out c matter and energy are cycled never created nor destroyed d although energy is degraded so it doesn t cycle so well the Second Law of Thermodynamics Natural systems tend to be in balance relatively stable over the long run 1 we know that any system with an out ow Rivers take sediment from continents to the sea must have an offsetting in ow Something brings sediment back onto the land a formula Iinput Ooutput b the input always ends up as output c the output can only come from input 2 even if we cannot see it we should believe the return ow is there a otherwise we would have run out of mountains or whatever a long long time ago b we don t expect to see significant net change in a planet 5000000000 years old within our paltry lifesp ans But in the short run systems don39t need to be in balance because of storage 1 it rains today but the output stream ow doesn t happen immediately 2 lakes soil groundwater glaciers hold water between rainfall and runoff from the rivers 3 IOASt Course outline Geography 113 Spring 2008 5 4 the input can go to increase storage or the output can come from decreasing storage in the short run 5 however ASt 0 in the longrun all the water going into lakes will leave eventually It is not a coincidence that natural systems are stable but rather an outcome of the fact that natural systems that are homeostatic inherently resistant to change survive while others are destroyed Key ideas in homeostasis 1 feedback the state of the system affects inputs or outputs 2 negative feedback an increase in storage will decrease input or increase output a example thermostat too much heat I St of heat turns off furnace linput of heat or turns on air conditioner I O b very common in natural systems animal population stream ow climate physiological systems c physical analog to negative feedback a marble in a bowlrolls back into center of bowl when displaced perturbed 3 positive feedback more storage yields more inputyields more storage yields more input or less storage means less input a continues until input energy is gone or system is broken the positive feedback system destroys itself b ex bonfire earthen or ice dam snow cover amp temperature c selfdestructive systems like this are uncommon in natural circumstancesfor obvious reasons d positive feedback systems can be stable for a long time until a threshold is crossed a pile of firewood is stable until it crosses a certain temperature e physical analog of threshold pop bottle on its neck stable until it tips past a certain point The equilibrium state 1 If the state of a system is the dj 39erence between two opposite forces average temperature balances the day s sunshine against night39s cooling e g we should see the system nd a balance which re ects equally the in uence of the two factors 2 this is the optimum an intermediate value of anything the angle of a mountain slope for example toward which a system will tend 3 the Goldilocks principle Not too hot not too cold but juuuust right 4 optimum doesn t necessarily mean good the ecologically optimum number of mosquitoes is more than none Storage and lag 1 storage smoothes out variation over a time a big bank account smoothes out changes in income 2 storage delays the response of the system to change a lake fills and empties more slowly than a pond a big truck speeds up or slows down later than a little one 3 the time difference between external change and internal response is called lag Course outline Geography 113 Spring 2008 Two Meditations by John Barth 1972 Niagara Falls She paused amid the kitchen to drink a glass of water at that instant losing a grip of fifty years the nextroom ceilingplaster crashed Or he merely sat in an empty study in Marchday glare listening to the universe rustle in his head when suddenly the five foot shelf let go For ages the fault creeps secret through the rock in a second ledge and railings tourists and turbines all thunder over Niagara Which snow ake triggers the avalanche A house explodes a star In your spouse so apparently resigned murder twitches like a fetus At some tri ing new assessment all the colonies rebel Lake Erie The wisdom to recognize and halt follows the knowhow to pollute past rescue The treaty39s signed but the cancer ticks in your bones Until l d murdered my father and fornicated my mother I wasn39t wise enough to see I was Oedipus Too late now to keep the polar cap from melting Venice subsides South America explodes Let39s stab out our eyes Too late our resolve is sapped beyond the brooches III ENERGY Att Lift ott atten mtgwhat dtpmas m mtgag it is pm c ht fondammtot camcfpts m scigmcf Pgt motion source of light Energy drives every temperature change chemical reaction change in 1 Natural work includes wind heat erosion soil development plant and animal life rain stream ow decomposition of chemicals a Energy arrives in sunlight wind streams plants food heat b Nothing happens without a source of energy c we should pay attention to where that energy comes from in order to understand nature 2 Arti cial work includes heat light manufacturing transportation chemical fabrication a Energy arrives as fuel electricity animal work etc b Nothing happens without a source of energy c we should pay attention to where that energy comes from in order to understand society B The laws of thermodynamics the theory behind how energy is used 1 First Law of Thermodynamics Energy is neither created nor destroyed No free lunch Course outline Geography 113 Spring 2008 7 a Because of the First Law we can treat energy as stuff energy accounting works as though energy were material b Common units for energy are calories amount of energy needed to heat one gram of water one degree Celsius 2 Second Law of Thermodynamics Use of energy degrades it toward lower value less usable less pure energy nally to uniform heat thereby eliminating the energy s utility although the energy is still there You cannot make a perpetual motion machine a Entropy is the concept of disorder that the degraded energy represents We can extend the idea to include material pure material iron ore for example contains less entropy Any change mixing eg increases the entropy b One form of energy can be turned into another amp back again 1st Law but there is an energy loss in each change 2nd Law c All energy ends as heat the heat death of the universe will come everything will be lukewarm amp brown material ends up mixed purity is expensive amp rare IV BIOLOGICAL PRODUCTIVITY The mgtm that artts the tacsgrsttm c mm we we pmt All energy to support life on earth comes from the sun energy cascades through the ecosystem passes from one user to another used once by each Energy is fixed by photosynthesis the key reaction for life on earth 1 the equation 6H20 6C02 solar energy gt 06H1206 602 2 06H 1206 represents xed carbon carboncarbon and carbonhydrogen bonds containing more energy than the carbonoxygen bond 3 only well almost only green plants do photosynthesis Respiration is the reverse process which releases energy from the fixed carbon 1 opposite of photosynthesis 06H1206 6026 gt H20 6C02 biological energy 2 done by all living things 3 equivalent to combustion you burn sugar and release work same as a steam engine would Biomass is the general term for fixed carbon 1 we ll use it as a measure of energy content two slices of bread is twice the biomass of one amp twice the energy note that we are using mass as a measure of energy 2 the biomass content of an ecosystem which may be the product of many years of growth is the standing crop Productivity is the rate of biomass production I typically measured as grams of xed carbon meter2 year Course outline Geography 113 Spring 2008 2 productivity limited by supply of nutrients water sun ranges between 3 gm2yr desert and 4000 gm2yr tropical coral reef 3 Limiting factors suppress productivity lack of rain in the desert etc 4 Net primary productivity is plant productivity minus plant respiration Ecology is the interaction between the organisms in the environment different species can be predators prey competitors symbionts etc Animals are consumers live only off of ultimately plant biomass 1 herbivores eat plants primary consumers 2 carnivores eat animals secondary consumers 3 and decomposers eat whatever is left after whatever happens 4 energy cascades through system each level receives from the previous The productivity of animals is far lower than the productivity of plants say 10 1 plant energy dispersed by animal life processes feeding warmth movement 2 Second Law of Thermodynamics would have predicted this less available energy after the use in consumption 3 concept the trophic pyramid each level has a fraction the productivity of the level below it although the standing crop can be higher than in the layer below 4 the productivity of top carnivores of long food chains sharks for example is very low square miles of grass support one lion Necessary ecological concept for understanding prey amp predators and much else 1 rselected organisms disturbance tolerators a reproduce rapidly invest little into each propagule make many each with little defense or food to grow on b respond well to uctuating environment but not competitive in stable environment a I c examples flies rats weeds rapid or rat stands for rate in an ecologists equation or 2 Kselected organisms a reproduce slowly invest much in each offspring it is large at birth long gestation defensive slow to maturity favor stable environments b examples elephants trees large carnivores humans cactus c Kselected organism favored in competitive or stressed environments forests or deserts d both pioneer and climax vegetation should be Kselected Nutrients are cycled within the ecosystem 1 the same phosphorus may be used by a tree today as 5000 years ago at the same spot the same sunlight cannot 2 soil is the shortterm 1000 year pool of nutrients good soils are those that cycle well accept hold amp release nutrients and water Course outline Geography 113 Spring 2008 9 3 decomposers are organisms which break down dead tissue release nutrients for another plant 4 nitrogen carbon water are atmospheric pools fast cycling after loss Nitrogen must be xed before it is available to plants 5 phosphorus calcium potassium iron etc are in geologic pools as long as 100000000 years between loss of the nutrient from the land to the sea and reappearance on land through erosion uplift weathering V HUMANS IN THE ENVIRONMENT 39 ts important 10 555 new wt Mstm a t and new M dt ftr ma animals A Humans are animals We have the same needs as other animals 1 animal requirements which humans have food etc 2 tens of millions of years ago primates were affected by adaptations during our arboreal treedwelling period predisposed us to be social familial visual vocal toolhandling etc 3 humans evolved in Africa over the last million years became taller verbal and tool us1ng 4 much more recently 40000 years environmental di 39erences fostered evolution of super cial di 39erences we see as race pigment hair body build all environmental responses B Humans are more than animals We have culture which animals don t 1 culture learned adaptation a increase our range and density because of what we know b includes technologies fire elevators c includes social adaptations language insurance 2 result of culture humans cover the earth a the great migrations to everywhere b habitation in many environments desert rainforest tundra c efficient resource use 100 s of foods d civilization cities writing monumental architecture C Because of our culture humans have thousands of times more ability to change damage or improve the nonhuman environment than we once did 1 The story of environmental impact is the story of technology 2 l fPAT as a simple construction of this a l human impact the ecological footprint is some function of P population A their af uence and T the level of technology they bring to their lives 9937 10 Course outline Geography 113 Spring 2008 V1 THE HUMAN POPULATION s pyti ppttt ti pm the met Vtvtmmmemmt pm a em 2 A The general issue C 1 people make environmental problems 2 more people make more problems 3 some problems emerge once population cross certain thresholds 4 the population is now increasing rapidly as are environmental problems How to talk about population some statistics 1 population the number of people in a given place a Is this an environmental important factor b Is a country with more people always worse off c What other factors are important Population density for example 2 growth rate population change per year in percent 3 crude birth rate births per thousand people per year 4 crude death rate deaths per thousand people per year a crude differentiates these rates from ageadjusted rates births per thousand women between 15 and 45 for example 5 GR BR DR 10 net immigration which is usually close to 0 a means all change in population is birth death or migration b dividing by ten is only to change a perthousand to a percent c expressed as a percent change per year like an interest rate d a high GR can be caused by a high ER or a low DR or both Exponential growth 1 a constant percent growth 35 for example is not a constant amount of increase or decrease 2 each year increases previous year39s population by 35 and increases the increase look at what happens to 100000000 people over three years at 35 growth which is the same as multiplying by 1035 100000000 1035 103500000 growth is 3500000 100000000 1035 1035 107122500 growth is 3622500 100000000 1035 1035 1035 110871788 growth is 3749288 3 See why it s called exponential growthquot 3 years growth 100000000 1035 1035 1035 is the same as 100000000 10353 4 lesson constant percent increase means that a population increases at an increasing rate Course outline Geography 113 Spring 2008 I 5 a meaningful and powerful statistic doubling time a length of time until population is twice a given level b constant for a given growth rate c value is approximately 07GR x 100 a 10 GR yields 7 year doubling time d note that doubling time is less than 10GR 10 GR yielding 10 year doubling time because of compounding like compound interest 6 description of phenomenon the Jshaped curve 7 can reach any size population we wish to name 100 billion 2000 billion the biotic potential is unlimited 8 Philosophical note Exponential growth is only a heuristic a simple informative model not a rm prediction it is a way to understand the world but not to predict the future We ll see more heuristics D Importance of population growth beyond mere increase in size 1 Age structure a demonstrated with apopulation pyramid a histogram graph of number versus category of age groups shows history of when growth or decline happened in that population helps predict future growth numbers of new mothers eg illustrates dependency ratio percent nonworking people 9937 disproportionate investment required for children39s needs schools hospitals dairy eg 2 Increasing needs a economy must expand to stay constant b more jobs needed for incoming workers E How does a country lower its death rate that is why do people die and how can it be prevented 1 causes infant mortality infectious diseases famine 2 prevention sanitation inoculation disaster relief 3 simple cheap medical technological intervention F How does a country lower its birth rate that is why do people have children and when will they stop I value of children in a sick poor agricultural circumstance 2 cost of children in a healthy rich industrial circumstance 3 slow expensive social and value changes needed G The demographic transition 1 a change happens between high constant BR amp high variable DR and a low constant DR and low variable BR as a country develops 2 it is easy for a country to lower its DR and hard to lower its BR DR drops years earlier 3 the time between the two events is the time of fastest population growth 12 Course outline Geography 113 Spring 2008 4 the poorer the country the longer the transition will take 5 the best way to lower the GR of a poor country is to make the country rich 6 but remember I PAT rich people have more impact Vll OVERPOPULATION A Biological definition exceeding carrying capacity 1 carrying capacity maximum stable population density 2 consequences of exceeding it a starvation predation illness reproductive dysfunction b environmental degradation overgrazing 3 result approximate equilibrium although populations will uctuate above amp below B Human cultural version Rev Thomas Malthus the Malthusian theory 1 the passion between the sexes shall continue unabated the biotic potential is unlimited 2 human population shall grow at a geometric rate as 4 9 16 25 36 exponential actually 4 8 16 32 64 3 food supply will increase linearly as 2 3 4 5 6 nobody knows why he though that but surely there are limits to growth of food production 4 population will exceed food supply eventually 5 resulting in famine pestilence or warfare 6 unless we choose a negative check virtue C NeoMalthusianism a more modern statement of this widely held by the biologists who were important early on in the 20th Century American environmental movement Darwin read Malthus and recognized the significance of excess births for all animals 1 human population has the potential to exceed its carrying capacity 2 starvation is inevitable 3 many other environmental problems are direct amp indirect results of overpopulation a resource depletion b pollution 4 population control must be the rst priority in environmental maintenance 5 we are already well past carrying capacity hunger and environmental degradation are apparent D AntiMalthusianism economists and others know that humans are more than just animals Marx read Malthus and recognized that there must be more to the ability of the land to support people than just its qualities different modes of production eg 1 carrying capacity is culturally varied 250000000 modern Americans where 2000000 Native Americans lived 500 years ago which is the carrying capacity Course outline Geography 113 Spring 2008 13 more people is much more ability to produce food group work irrigation dams eg and innovation steam power e g and people are good anyway the hunger we see is a product of human choices economic systems wealth warfare pollution is not created directly by people dependent upon level of technology one American produces as much pollution as ten Chinese Malthusianism can disguise racism should we discourage reproduction of brown amp black people more than white people we have never been any good at predicting the future knowing what productivity will be for example Environmental ethics in a densely populated world rPPONE What is ethics An ethical tool the ecological footprint Cowboy economy our footprints don t overlap from Kenneth Boulding Spaceship economy we breath each others eXhalate 14 Course outline Geography 113 Spring 2008 Man39s march to the summit Kenneth Boulding 1955 The Conservationist s Lament The world is finite Resources are scarce Things are bad And will be worse Coal is burnt And gas exploded Forests cut And soils eroded Wells are drying Air39s polluted Dust is blowing Trees uprooted Oil is going Ores depleted Drains receive What is excreted Land is sinking Seas are rising Man is far Too enterprising Fire will rage With man to fan it Soon we39ll have A plundered planet People breed Like fertile rabbits People have Disgusting habits Teehnologist s Reply Man s potential ls quite terrific You can t go back To the Neolithic The cream is there For us to skim it Knowledge is power And the sky s the limit Every Inouth Has hands to feed it Food is found When people need it All we need ls found in granite Once we have The men to plan it Yeast and algae Give us Ineat Soil is almost Obsolete Man can grow To pastures greener Till all the earth ls Pasadena Moral The evolutionary plan Went astray By evolving Man Moral Man s a nuisance Man s a crackpot But only man Can hit the jackpot Course outline Geography 113 Spring 2008 I5 VIII POPULATION CONTROL A The issue too many people is a problem it also creates or aggravates other B problems Technical aspects of the solution are simple contraception abortion abortificants etc are well developed technology although liability laws have discouraged development of new kinds of birth control in US Human aspects of problem are intractable 1 moral or religious objections use of abortion as birth control or seX choice e g 2 male selfimage domination who makes decisions who sees the problems more closely 3 individual liberties Chinese systems of strict legal limit on number of children does work do we want it here 4 labor requirements oldage maintenance etc demographic transition issues This contradiction is the Tragedy of the Commons a recurring block to us solving environmental problems Garret Hardin gave it that name and this formulation The best choice for the individual may be the worst choice for the group 1 The commons is a common grazing land in traditional European society eg the Boston Commons a by extension a commons is any free but finite resource fisheries clean water park benches b called a common property resource accessible by all with no owner If it is overgrazed it will degrade and support less To the whole group the optimal number of cows willbe for example 5 per person To each individual the optimal number of cows willbe dozens and dozens If each individual makes hisher choice freely the commons will be degraded QPWN That39s why we need laws or ethics or religions or families or whatever makes us operate toward the interests of all 7 Central idea the market the idea that prices come from the interaction of supply and demand and bring all the crucial information about consuimption to consumers that is we can buy it if we can afford it 1639 Course outline Geography 113 Spring 2008 IX AGRICULTURE IN HUMAN HISTORY A Purpose feed more people by increasing human carrying capacity of an area B Operation control limits of environment water nutrients pests etc and breed plants adapted to those limits C Origin important to understanding the requirements and the problems of agriculture 1 Paleolithic old stone age subsistence was huntinggathering like another animal a example the IKung bushmen of Namibia b One of the harshest environments in the world Kalahari Desert c IKung subsistence 15 hours a week gathering mongongo nuts d IKung healthy longlived environment stable and reliable 2 Neolithic origins of domestication plants and animals with higher productivity and useful traits wool big seeds simultaneous ripening etc a with agriculture Mexican peasants for example b sixtyhour work weeks little protein more disease vulnerability to political subjugation 3 Why make the switch We were better off before a Key element in IKung system was population density at about onethird carrying capacity b Methods of maintaining population levels were traumatic infanticide late marriage yearslong abstinence protracted nursing c Lose control of population density and intensification domestication inevitable d Key to agriculture is that a little more labor is always a little more food a little more hunting is not always a little more food e Neolithic began all over world after settlement had expanded into every corner of the globe and every ecological niche the planet was full D Conclusion about role of agriculture in human evolution 1 increased carrying capacity dramatically 2 increased workperunitfood even more dramatically 3 we cannot go back to gathering mongongo nuts unless most people die 4 agriculture permitted civilization buildings and writing and war kings and peasantry 5 and we shall see it is the most widespread negative impact on the global environment Course outline Geography 113 Spring 2008 I7 X MODERN AMERICAN AGRICULTURE The mics meditative and mics destructive facet system ever xenonVt A General ecological circumstance 1 2 3 4 simplify ecosystems to remove what we don t use amp stop competition favor superweeds rselected plants the right qualities for crops decrease limiting factors provide pmtection from competitors amp predators B Systems amp cycles view an unstable system 1 2 3 4 goal is an output food therefore not inherently stable net inputs fertilizer etc must mean a net output pollution weeds amp crops are a temporary stage in any ecosystem rselected thus a b C unstable p oor cyclin g poor protection soil erosion etc degrading future agricultural potential C The processes of agriculture 1 plow turn over topsoil a b why remove weeds improve seedbed sideeffects dramatic rapid nearpermanent soil loss because atmospheric energy is exerted directly on the soil raindrops streamlets wind preventing problems decrease amount of uncovered soil notill or decrease stream energy across fields stripcropping contour plowing terraces fertilize add inorganic mineral nutrients P N K Ca not present in soil or lost from soil after erosion a b why increase productivity replace lost nutrients sideeffects costly limited supply nonrenewable encourages pollution downstream eutrophication as in Chesapeake and upstream where produced this is an externality to the market the cost of polluting someone else s stream C doesn t hurt the farmer s profit preventing problems decrease soil erosion recycle nutrients more effectively manure management plant hybrids giant defenseless very thoroughly domesticated plants in extensive plots monoculture a b why grow faster utilize fertilizer effectively tastier economies of scale sideeffects vulnerable to pests dramatic failures like the potato famine reliant on farmers amp inputs and cost permanent loss of diversity preventing problems miX crops rotate crops preserve diversity accept lower productivity 18 Course outline Geography 113 Spring 2008 4 pesticides chemical poisons for weeds and insects a why plants are more vulnerable insects not us consume 40 of biomass in natural communities chemicals are very cheap b sideeffects often less productivity after a few years 1 insects evolve resistances very fast as nonresistant ones are killed 2 more toxic up food change preferentially kill our friendly insects before enemies 3 persistent poisons potentially dangerous to humans mammals birds Agent Orange c preventing problems 1 use natural enemies support previous ecosystem import natural predators 2 limit pesticide use to times when pests are obvious integrated pest management 3 use nontoxic controls traps pheromones D Summative critique of modern American agriculture 1 unstable 2 inefficient in a land use b food quantity per input c resources energy chemicals water 3 polluting 4 expensive 5 but very effective in getting you and me a good rich healthy diet XLFEEDING THE NEXT BlLLlONS Fwd pmdmtipm or I39M awt A Premise the present world population is undernourished and there will be still more people in the future How will they be fed B Evidence the Famine What causes intense food shortages QPWN not enough total food environmental degradation low income too many people failures of the market collapse of social economic political transportation system Course outline Geography 113 Spring 2008 19 C Can Americanstyle agriculture feed the world Its strengths here are weaknesses elsewhere Interlude what does efficient mean about agriculture It should be lots of output per unit input but is that food per land input Per capital input Per material input fuel water etc Per hour of labor 1 American agriculture minimizes labor inputs through pro igate use of land fuel chemicals capital poor nations have much labor but little land fuel chemicals capital American agriculture overcomes instability by buying transporting food so we don t get famines and changing inputs poor nations can suffer disasters if crops fail or decrease Americanstyle agricultural technology acts to disrupt many aspects of the food system in poorer countries a land tenure systems 1 landlords kick peasants off land and hire them to farm it 2 wagelabor decreases access to food b economic development 1 debt is necessary to buy hybrids fertilizer fuel 2 excess labor underemployed labor becomes unemployed and migrates to the city c ecology people are dependent on many parts of agriecosystem fish eg which get poisoned or degraded d nutrition single crop rice displaces higher protein lentils etc higher productivity needed mean more protein e stability widespread use of a single cultivar crop type encourages catastrophic pest infestation f exibility cannot return to old system after investment in pumps tractors crops cannot be grown on moderate levels of inputs D The converse what can Americans learn from Thirdworld agriculture 1 2 3 increase ef ciency by utilizing what would otherwise be waste detritus decrease pollution through the same means waste was pollution more labor means higher ef ciency and less degradation use all the land repair damage early recognize noneconomic value of farmland a use land appropriately to its qualities and its permanent value b make decisions according to the interests of the seventh generation meat is very inefficient 25 or less and inhumane vegetarian USA could feed an extra billion E Can we increase the area under cultivation 1 2 only a little bit most soil is inappropriate to food production we can breed new crops drought resistant or tree crops for problem environments 20 Course outline Geography 113 Spring 2008 3 if we do so it is at cost of organisms already there rainforest e g F The oceans will save us 1 the open oceans are a desert a the nutrients sink below the thermocline b fish are concentrated in shallow waters or areas of upwelling 2 we eat high on the trophic ladder in the sea and are thoroughly over shing already 3 we can harvest lower on the pyramid kelp krill or farm choose and manage species but this will displace existing populations Xll RESOURCES Mhm Mt tnvz mmmgmt gab 55 M5 10 M55 A Concept material in the environment of use to us Culturally defined value of materials different to different peoples different times B Renewable vs nonrenewable resources a fundamental but vague distinction 1 all resources are produced by natural processes of course and essentially all natural processes still work at some rate so all resources are technically renewable 2 renewable rate of production approximates our use rate human life span 100 year forest regrowth 3 nonrenewable natural production much slower than use 100000000 years for oil 4 mineral resources are the usual type of nonrenewable resources Xlll MINERAL RESOURCES Mimmm s Mg sigmaam Kymth cfmpwrmmmwt MSWMCES A Value of mineral resources is in their concentration 1 a fundamental tendency for material in the natural world is toward disorder called entropy and it always increases 2 only energy can increase material order at the cost of the entropy the useable quality of the energy 3 it is far more than 1000 times more dif cult to obtain a gram of gold which is 1999Lh of 1000 grams of rock than that which is 51 of 2 grams of rock a the last bit is always the hardest to get b example the first Easter egg is easy to find the last is hardest c note that in the 51 gold case you can throw away millings already processed ore which are better than 1999th gold the ore in the second case 4 if nature do not make a highly concentrated ore then we have to and our energy is more expensive than nature s Course outline Geography 113 Spring 2008 2 Natural processes concentrate ores 1 all such processes take energy examples stream sorting chemical precipitation ground water or hydrothermal sul de deposits 2 all such processes are rare and rarely preserved organic material must be buried without oxygen not over heated brought near surface coal or trapped beneath impermeable layers oil gas We use the best most concentrated resources first Of course 1 the set of resources all of the iron eg are divided into a reserves those of commercial value in concentration or in accessibility reserve will increase or decrease as price changes b known reserves are those we can find stages in resource exploitation 1 early price drop with better technology economies of scale more exploration 2 price rises from depletion supply amp demand more cost to extract 3 increased efficiency recycling cause it pays now 4 nally substitution with a another nonrenewable resource of lesser value b a renewable resource which is now commercially feasible because prices are higher Role of recycling 1 postpone depletion 2 prevent price increases which cost everybody money 3 make money from resource 4 decrease wastestream XIV ENERGY amp ENERGY RESOURCES TM altimmr Mspwct mm mpzmt txp md w clt m mg cthtr macaw Importance of topic 1 high energy use underlies modernity industrial economies a per capita energy use correlated with income b example of modern agriculture c impact of oil embargo Persian Gulf war 2 energy a limited resource a fossil fuels coal oil natural gas are nonrenewable natural production rate essentially zero they will run out b renewable energy resources solar energy hydroelectric power wind energy produced at lower rates than we like to use c efficiency with which we use resources can vary greatly can change impact and rate of depletion Course outline Geography 113 Spring 2008 energy production and use has severe and widespread imp act a mining coal oil spills b air pollution smog in cities c acid rain affecting 1000 s of square miles of forest d Greenhouse effect will change global climate Nonrenewable resources 1 processes which are making for example coal work very slowly 1000000 times slower than we use it 2 examples oil coal natural gas uranium 3 depletion curve use must decrease and price increase as supply exhausted especially easily recovered supply 4 substitute resource will be needed which will be more expensive at least at rst Renewable resources 1 old as re wood was rst renewable fuel 2 examples wood or other biomass sun wind water dung 3 supply unlimited if we can wait that is ratelimited not supplylimited 4 larger capital requirements vs lower production costs Conservation 1 choose not to use extra energy instead of nding new energy 2 cheapest energy source power companies now investing in home insulation to save fuel rather than in new plants 3 savings projected far into the future which is good and bad 4 enduse design matches quality of energy to use heat is cheap due to second law of thermodynamics energy use degrades it to less useable lower quality energy 5 cogeneration waste heat can be used analogy to trophic levels some food is left in the ecosystem after fancier users are done 6 counterargument more energy production means more economic growth Pollution from extraction 1 degraded land and disrupted settlement ex Shamokin amp other anthracite towns destroyed vegetation acid drainage boomandbust economies 2 oil spills especially on the ocean and in coastal waters serious damage in critical environments Total cost of energy use Premise the price we pay directly for energy is a small part of the total cost 1 The market provides a price for energy what are the components of that price Dollar costs for renergy a price goes to labor land owners new investment dividends amp interest b see also energy content of manufactured goods aluminum plastics transportation 2 Course outline Geography 113 Spring 2008 23 Total cost is the market cost price you pay at the pump plus some hidden costs a Environmental costs 1 dollar costs lost fisheries or lumber 2 plus a multiplier lost fishery jobs also decrease boat sales 3 nondollar costs incommensurables dead birds a what39s a dead sea otter worth The 35000 Exxon spent on them A zoo can buy one for 750 b plus ecosystem effects fewer salmon mean fewer bears c hard to measure but maybe 50000 excess deaths from SO2 mostly people already sick very young or old 4 uncertain but possibly extreme future damage greenhouse effect causing extinction of half the species on earth 5 Example of ANWR how to choose b Social costs etc military protection for Persian Gulf tax breaks XV AIR POLLUTION Cow Egpmdmt mydgmitg tX Mrplf yumtm d tg Almost all air pollution from fossil fuel use 802 C02 NOx HC Severe health risk 50000 deaths per year from coalfired power plants Acute local impacts smog in a city where input is very high Regional impacts down wind from industrial regions from acid rain 1 2 3 4 5 02 and NO from combustion makes acid rain kills trees lakes varies according to resilience of local environments buffering capacity delayed impact as buffering is depleted or as organisms age or as other disruptions storms e g amplify effect most acidic rain in nation in central Pennsylvania Global impacts from carbon dioxide and a few other gases see above XVI HUMANINDUCED CLIMATE CHANGE TM biggtst human impact arr History 1 it is clearly the case that climate have changed in the past a New York City was under glacial ice 18000 years ago b the previous interglacial provided a subtropical climate here Course outline Geography 113 Spring 2008 2 data geologic deposits glacial till soil coastlines biological evidence pollen fossils geochemical traces Causes What drives changes 1 external forces planetary cycles amp asteroids 2 internal internal to the atmosphere forces are we one 3 Lots of feedback makes it unpredictable Temperature response of atmospheric system example of accelerated Greenhouse effect 1 CO2 slows cooling through atmosphere 2 concentration rising 270 ppm in 1800 to 360 now 3 globe may be as much as 10 C warmer in 2100 4 melt ice caps shift rainfall zones extinct ecosystems 5 most severe impact on least powerful population like any catastrophe Complexities 1 there is direct driving a more C02 higher temperature b reach a new equilibrium state 2 but negative feedback pervades system a more C02 means faster uptake by natural sinks ocean vegetation b higher temperature means higher evaporation means more clouds means less sun 3 and some positive feedback too a warming releases C02 amp methane from tundra ocean b less snow means more insolation at high latitudes means less snow Uncertainty we don t know what s going to happen 1 predictability is very low we don t know much about conditions so di 39erent from present ones Our models are poorly calibrated for extreme conditions 2 the best models provide a wide range of possible outcomes dependent of certain parameters we cannot yet measure precisely cleanliness of the snow cover amount of methane to be released in the Arctic 3 it is nearly certain that the details of our models will change dramatically in the next few years as they has in the past few years as we learn more 4 some rational scientists expect very little temperature response to the response more negative feedback than positive for example but fewer scientists doubt the visible significant imp act each year Overall response of atmosphere to higher temperature 1 higher temperature shifts weather bands poleward Kansas gets Texas weather Sahara becomes Tropical wetdry while Italy becomes Sahara 2 temperature change greater at higher latitude direct insolation a lower of total heat 5 Course outline Geography 113 Spring 2008 25 storms monsoons more intense more heating most are reluctant to say whether change has begun variation is inherent in system but a consensus is growing indirect outcomes coastal ooding collapse of agriculture extinctions storms G A policy nightmare How do we respond politically to a problem that mightor mightnot give us incomparably bad problems XVII BIODIVERSITY A What is it 1 Biological diversity the relative diversity among organisms present in di 39erent ecosystems a genetic diversity diversity of genes within a species Important to the stability of a species evolutionary bottlenecks of cheetahs Amish b species diversity diversity among species diversity of populations of organisms and species but also the way these organisms function c ecosystem diversity diversity at a higher level of organization In each ecosystem living organisms are part of a whole they interact with one another but also with the air water and soil that surround them B Where does it come from 1 2 Biodiversity is the result of 35 billion years of evolution Until the emergence of humans the Earth supported more biodiversity than in any other period in geological history Estimates of global species diversity vary from 2 million to 100 million species with a best estimate of somewhere near 10 million C Benefits of biodiversity Ethics is the set of reasons we use to choose an action why we do what we do 1 in this sense ethics doesn t mean what we think ethical means right be some particular standard Criminals robs and cheat because it is appropriate within their ethical universe Why is anything important The interaction con ict of human and nonhuman values a instrumental value something is an instrument for me to use an anthropocentric perspective b intrinsic value the value of an organism is defined beyond my relationship to it one approach to ethics is to ask what entity is at the center of a descision me my children my dog all people one simple structure ETHICALREALMxlISCALEe I individual I aggregate I human I egocentric I ethnocentric I Course outline Geography 113 Spring 2008 nonhuman I biocentric I concentric 0 could also dj 39erentiate self others animate inanimate young old etc consider the market as an ethical structure Ecological role of biodiversity borrowed adapted from Wikipedia a Species provide function to an ecosystem They can capture and store energy produce organic material decompose organic material help to cycle water and nutrients throughout the ecosystem control erosion or pests fix atmospheric gases or help regulate climate b Ecosystems also provide various supports of production for humans soil fertility pollinators of plants predators decomposition of wastes and services such as purification of the air and water stabilization and moderation of the climate decrease of flooding drought and other environmental disasters These functions are important for ecosystem function and human survival c Research suggests that a more diverse an ecosystem is better able withstand environmental stress and consequently is more productive 1 The loss of a species is thus likely to decreases the ability ofthe system to maintain itself or to recoverfrom damage or disturbance 2 An ecosystem with high biodiversity may have a greater chance of adapting to environmental change The more species comprising an ecosystem the more stable the ecosystem is likely to be Economic role of biodiversity The biodiversity is the one of the bigger wealths of the planet and nevertheless the less recognized as such EO Wilson a For humans biodiversity a resource for daily life Eg 39crop diversity39 b Biodiversity is a reservoir of resources 1 biodiversity provides food crops livestock forestry and fish 2 7O of the promising anticancer drugs come from plants in the tropical rainforests c Ecotourism biodiversity is a source of economical wealth for many areas d The majority of species have yet to be evaluated for their current or future economic importance Ethical role of biodiversity a biodiversity is to be a mirror of our relationships with the other living species an ethical view with rights duties and education 1 If humans consider species have a right to exist they cannot voluntarily cause their extinction 2 biodiversity is also part of many cultures spiritual heritage see indigenous people and cultural diversity b the market provides no value for nature beyond the instrumental Scientific role of biodiversity a Each species can gives a clue as to how life evolved b biodiversity helps scientists understand how life functions and the role of each species in sustaining ecosystems c A biodiversity hotspot is a region with many endemic species 1 Usually in areas of historically limited human impact and are generally very productive 2 Most of these hotspots are located in the tropics Course outline Geography 113 Spring 2008 27 3 Human activity in many of these areas is increasing dramatically 4 coral reefs mangroves eg 5 Brazilian rainforest is said to represent 15 of the world biodiversity with 50000 plant species 5000 vertebrates 1015 million insects millions of microorganisms etc D How is biodiversity threatened 1 The majority of biologists believe that a mass extinction is under way a estimates rates range from a handful to upwards of 200 species a day lost b most scientists believe that the rate of species loss is greater now than at any time in human history with extinctions occurring at rates hundreds of times higher than background extinction rates c Some studies show that about one of eight known plant species is threatened with extinction d Every year between 17000 and 100000 species vanish from our planet This figure indicates unsustainable ecological practices because only a small number of species come into being each year e Some people say that up to 15 of all living species could disappear within 30 years Nearly all say that the losses are due to human activities in particular destruction of plant and animal habitats a An increasing number of studies indicate that elevated rates of extinction are being driven by human consumption of organic resources b While most of the species that are becoming extinct are not food species their biomass is converted into human food when their habitat is transformed into pasture cropland and orchards 40 of the Earth39s biomass is tied up in livestock and crops d An ecosystem decreases in stability as its species are made extinct the global ecosystem faces collapse if it is further reduced in complexity 0 Biodiversity and size bias The vast majority of Earth39s biodiversity is microbial and that contemporary biodiversity science is quotfirmly fixated on the visible worldquot Microbial life is very much more metabolically and environmentally diverse than multicellular life On the tree of life visible life consists of barely noticeable twigs This should not be surprising invisible life had at least three billion years to diversify and explore evolutionary space before the 39visibles39 arrivedquot E Extinction the extreme case of biodiversity loss 1 loss death of gene pool of a species not just an individual like when we die a a species is a population which can interbreed the basic kind of organism b a lesser version loss of genetic diversity Within a species corn tigers Significance irreplaceable that combination of genetic material will never occur again it is the creation of the billions of deaths that drive evolution The big picture over time a extinctions occurred repeatedly through out geologic history at most period ends CretaceousTertiary dinosaurs etc Jurassic the big one PleistoceneHolocene mammoths etc b specific causes identified or presumed for each climate sealevel asteroid Course outline Geography 113 Spring 2008 XVIII CAUSES OF BIODIVERSITY LOSS Ecological adaptations Necessary ecological concept for understanding prey amp predators and much else 1 rselected organisms disturbance tolerators 1 reproduce rapidly invest little into each propagule make many each with little defense or food to grow on 2 respond well to uctuating environment but not competitive in stable environment 3 examples flies rats weeds r equation or rapid or rat stands for rate in an ecologists 2 Kselected organisms 1 V reproduce slowly invest much in each offspring it is large at birth long gestation defensive slow to maturity favor stable environments 2 examples elephants trees large carnivores humans cactus 3 Kselected organism favored in competitive or stressed environments forests or deserts 4 both pioneer and climax vegetation should be Kselected 3 Essentially all threats to biodiversity favor the r over the Kselected organisms Direct killing or collecting 1 hunting food trophies the lure of the almost extinct 2 commerce whales chimpanzees sea otters example whaling 3 predator control wolves bears coyotes eagles Pollution 1 DDT amp food chain osprey pelicans ex bald eagle 2 eutrophication like Lake Baikal ex humpback whales amp red tide H abitat loss 1 rainforest most obvious example 1 acresecond 2 also here bison cougar everywhere we cut our forests long ago 3 size of remaining plots signi cant must be enough to support large animals 4 climate change as a driving force ex coral reef E xo tics Environmental changes from thoughtless causes that will outlast the human species 1 de nition organisms introduced into environments where they are not native 9937 Course outline Geography 113 Spring 2008 29 familiar and apparently benign examples pigeons starlings dandelion corn Norway rat a permanent change in the world will survive for tens of millions of years if anything does our longestlasting environmental effect We expect exotics to be rselected travel well spread rapidly ex snakehead Spartina Four dramatic problems with exotics a Problem 1 human disturbance favors a shift to rselects organisms including exotics 1 examples weeds and pests that have developed and moved around with agriculture Med y dandelion bindweed 2 these become ubiquitous problems everywhere as we average the genes of the world Problem ll introducing unmatched organisms those with no natural enem1es 1 examples Japanese beetles Gypsy moth kudzu fire ants Africanized bees 2 eventually predators can be introduced or develop locally but population explodes first Problem 111 introducing diseases to populations without defenses 1 examples smallpox and measles into New World killed more native people than did Europeans SARS Dutch elm disease Newcastle39s disease Chestnut blight 2 can amp will extinct species long before defenses can evolve this is a slow process decay amp threshold ex distemper amp seals in Europe Problem IV the competitive disadvantage of island biota 1 small number of species evolve poorly into many niches on islands 2 predatory pressure weak so defenses are too 3 continental biota will consume or outcompete the islanders 4 examples deer in New Zealand half of Hawaii39s birds are extinct pigs goats amp mongoose in Hawaii amp Caribbean ex Hawaii rates of interchange are increasing ecological sideeffects a b collapse of food chain ex orcas and sea otters symbiotic species the dodo acacia and ants Course outline Geography 113 Spring 2008 XIX EXTINCTION Definition loss death of gene pool of a species not just an individual like when we die 1 a species is a population which can interbreed the basic kind of organism 2 a lesser version loss of genetic diversity within a species corn tigers Significance irreplaceable that combination of genetic material will never occur again it is the creation of the billions of deaths that drive evolution The big picture over time 1 extinctions occurred repeatedly through out geologic history at most period ends CretaceousTertiary dinosaurs etc Jurassic the big one PleistoceneHolocene mammoths etc 2 speci c causes identi ed or presumed for each climate sealevel asteroid The big picture now 1 gt 1000000 species described 2 2x 10x presumed undescribed how would we know how many 3 ninetypercent of species in tropical forests 13 are coleopterans beetles Human impact the numbers currently 1000x background rate XX WILD RESOURCES Mt we deptmdemt m V WAMS wags an Wily cyg misms Mt we yawn 51 themaghlg and quotM Mame O U U U cmmd tipm that pmt 2 My tmv mmmmt Harvesting living things 1 sh trees are examples 2 in this case we depend on natural productivity existing forests natural reproduction this is hunting and gathering like the IKung 3 clearly can be a renewable resource have been used for 1000 s of years 4 What happens as rate of use increases That is what is over shing or cutting a at low rates harvesting mimics natural losses may increase vigor like wolves strengthening caribou herds b higher 1 marginal productivity decreases in a limited lake 200 fishermen don t catch twice as much as 100 2 harvest rates exceed growth amp replacement rates 3 ecosystem changes forced up or down food chain 4 standing crop existing population of fish trees etc can postpone this effect a threshold to our observation c higher still Course outline Geography 113 Spring 2008 3 1 marginal productivity is negative more fishermen catch fewer fish 2 population collapses remove adults amp reduce offspring production 5 new technology makes this worse and increases ancillary ecological impact a drift nets superships strip mine the ocean deplete surface species completely chew up bottom structure b wholetree harvest clearcutting removes all habitat nutrients ground cover 6 this is literally the Commons sh in the ocean and we see here the Tragedy I39ll catch all I can and everyone will suffer 7 response to the Commons problem privatize wood lots versus government land legislate fishing season size and technology limits exert moral force Greenpeace boycotts educate sportsman clubs newts offer incentives debtfornature costsharing of habitat planting f empower the market bidding for licenses leases B Managing wild resources how do we minimize damage 1 maximum sustained yield harvest at at top of the curve or do we want the steepest part of the curve before serious ecological problems start while marginal productivity is still high 2 shift down trophic ladder to increase ef ciency harvesting krill versus harvesting whales although harvesting whales is currently more efficient like using cows to harvest fodder and this would take the whales food 3 farm fish or trees select species manage food supply or nutrients and competitors harvest at lower energy cost compared to traveling 100039s of miles in a boat but this has environmental problems of any farming ex eutrophication of Puget Sound introduced diseases exotic fishes 4 protect limited productive areas nearshore and estuarine areas have more nutrients compared to desert of open ocean also for the same reasons most vulnerable to pollution XXl E X 0 T l C S Emvz ymmgmt t Marga themghtltss a oat that will thst m human 52ch A definition organisms introduced into environments where they are not 11 ative B familiar and apparently benign examples pigeons starlings dandelion corn Norway rat C a permanent change in the world 1 will survive for tens of millions of years if anything does 2 our longestlasting environmental effect Course outline Geography 113 Spring 2008 We expect exotics to be rselected travel well spread rapidly Four dramatic problems with exotics 1 Problem I human disturbance favors a shift to rselects organisms including exotics a examples weeds and pests that have developed and moved around with agriculture Med y dandelion bindweed b these become ubiquitous problems everywhere as we average the genes of the world 2 Problem II introducing unmatched organisms those with no natural enemies a examples Japanese beetles Gypsy moth kudzu fire ants Africanized bees b eventually predators can be introduced or develop locally but population explodes first 3 Problem III introducing diseases to populations without defenses a examples smallpox and measles into New World killed more native people than did Europeans SARS Dutch elm disease Newcastle39s disease Chestnut blight b can amp will extinct species long before defenses can evolve this is a slow process decay amp threshold 4 Problem IV the competitive disadvantage of island biota a small number of species evolve poorly into many niches on islands b predatory pressure weak so defenses are too c continental biota will consume or outcompete the islanders d examples deer in New Zealand half of Hawaii39s birds are extinct pigs goats amp mongoose in Hawaii amp Caribbean rates of interchange are increasing XXII ENVIRONMENTAL HEALTH Fiaiai i Ca it is new tag tavimamgat pmttcts pm Mata that ma a mast 10 as as imafiyiaaai s General idea 1 much of health amp sickness is environmental and always has been 2 much of our interest in the environment is about its possible effect on our health 3 three topics ecology of vectors amp contagion human settlement toxins in the environment ecology of disease germs are organisms amp have an ecology like others do 1 vectors eg tropical diseases a mosquitoes amp malaria ecologic action draining swamps as response b Lyme disease amp ecology of dogs exotics carrying diseases farm animals eg beavers and giardiasis 2 Travelers disease others39 intestinal ora doesn t match your defenses 3 Course outline Geography 113 Spring 2008 33 genetic forces responding to environmental forces race qv sicklecell anemia lactase deficiency C human settlement how we live increases our exposures 1 contagion living close together is dangerous a most sickness is from improper water supplies very much a product of population density b cholera plague small pox are diseases of civilization c episodes of Asian u from Chinese pigs illustrate spread d smaller population protected 2 hungerrelated diseases result of settlement density D Health effects of pollutants 1 toxins a some chemicals we release into the environment are poisonous doing direct damage to human tissues kidney liver nerves skin reproductive organs b examples lead pesticides mercury TCE PCB etc c toxicity related to dose more is worse d exposure is significant variable lead poisoning in innercity children e from paint exhaust water pipes f lowgrade neurological damage cf decline of Roman empire g some chemicals heavy metals pesticides cumulative poisons stays in the body h biological amplification increases concentration of poisons up food chain example toxins accumulate in fishes from sediment at Minamata Hg James River kepone Hudson River PCB ocean tuna Hg Columbia River radiation etc 2 carcinogens a some chemicals that we release into the environmental induce physiological damage that causes or promotes uncontrolled cell proliferation cancer b psychologically important environmental impact c many most people carry personal tragedies from cancer 1 a major tool against industrialization 2 Delany clause prohibits any carcinogens in food additives no matter what the tradeoff d pattern of cancer implies environmental causes bad water air etc e specific chemicals exposures are linked to cancer in humans they are carcinogens smoking asbestos radon formaldehyde etc f animal models suggest more Ames test rodents g identifying imp act of carcinogens on humans is currently almost impossible for four reasons 1 Are there thresholds below which carcinogens have no effect that is what is the shape of the tail of the doseresponse curve If so we need not control low exposures as carefully as high exposures 34 Course outline Geography 113 Spring 2008 2 Which animal models are appropriate for humans Guinea pigs and rats respond differently by a factor of 1000 s to dioxin we don t know at all about humans 3 Background carcinogen levels may be very high 1 g per day of natural carcinogens from plant pesticides 4 Statistical methods cannot identify significant increases in a very rare event we are measuring excess deaths above background A relatively large clustering of a rare event or a small increase in a common event can be mere chance XXIII RISK 39 matters new dangers twy i mmmgmt i Manges we it matter mere WW damgemas we mime tmi mmmmtm Manges we The risk concept 1 we make decisions to avoid or accept environmental and other situations because we are concerned that they will hurt us physically economically or psychologically 2 thus our behavior can be thought of as choosing or rejecting risks 3 our responses to risk are very di 39erent for different risks of the same magnitude that is two things with equal chance of harming you are not equally scary Measuring risk 1 necessary before we can compare them scientifically 2 insurance companies do it all the time probability from previous experience x magnitude of loss your car insurance 3 for health sorry this is pretty clinicalsounding a chance of death b loss of years of life or quality of life c in law loss of lifetime earnings rich people s live are worth more or pain and suffering 1500000000 d a facetious concept the micromort what you get from an activity which increases your chance of dying by 1 in 1000000 1 14 cigarettes 6 minutes in a canoe 150 miles in a car 1000 miles in a jet 1 pint of wine 40 tablespoons of peanut butter 2 ignores length of life lost but permits us to comp are mortal risks How can we measure the value of a human life I obviously it is valuable beyond price but 2 people will sell micromorts a increase in pay to take an equivalentjob with increase risk b comes to about 480 per micromort equals 4800000 per life c the last micromort is worth more than the first of course 3 investment to avoid lossoflife standard amp inevitable engineering decision Course outline Geography 113 Spring 2008 35 a a million dollars was a ruleofthumb a few decades ago b but Ford got into trouble over the pinto for using a number 4 but this is statistical we cannot easily stop paying for a real person D When do we value micromorts more highly that is what risks seem biggest 1 high regret large or very noticeable losses at one time plane crashed involuntary living next to a chemical plant hidden chemicals radiation dreadful cancer nuclear war environmental collapse not helpful unlike medicines e g new renting a car with bad brakes versus not xing my own unfamiliar E What is the effect of this on policy NQQPWN 1 decisions are conservative favor speci c people ignore voluntary risks 2 rational consideration of tradeoffs not possible under many situations 40000000 micromort for hazardous waste cleanup XXIV SUSTAINABILTY Cam ME SSME that ayt gtmtmtipms gft cppmtumitits 147 Myst ME had A Definition of sustainability 1 Standard de nition The ability to meet present needs without compromising those of future generations 2 comparative ethical perspective seventh generation B Practical limits of the idea 1 the physical problem any change or use is a future loss 2 the cultural problem do we know what they want C Sustainability as a societal endeavor 1 we cannot solve isolated pieces of a broad problem 2 sustainability has social economic as well as environmental components 3 topical closure an environmental choice exists within a cultural system and cannot be considered independently sustainability of this system underlies the human future XXV FINAL THOUGHTS 0 TM Human Emyimmmgmt A Why go on Isn t it hopeless 1 Yeah but it always was We ve been abouttobeoverpopulated since Malthus about torunoutof petroleum since 1965 and so forth There s time Course outline Geography 113 Spring 2008 2 Organisms in the environment may be more resilient and adaptable than we can imagine Trees grow in cracks in the sidewalk humans thrive in Calcutta 3 The world is new to each newborn We see an open natural world in the forest or elds that have been drastically altered since 200 years ago what will our children see 4 Humans may pass but the earth abideth forever There will be shadbush blooming in the mountains in 10000 years if we figure out how to live sustainable or if we finish ourselves off Is this cheering you up yet 5 If we are depressed it is because we love the world and its beauty depression isn t a reason to stop Understand what is particular about human responses to these problems We see specific aspects of human psychology that moderate our responses 1 tragedy of the commons affects our abilities to think of the needs of others 2 a billion years of evolution prepares us to fear quick personal harm a tiger stinking water but not slow indirect subtle harm ozone depletion carcinogens lost of biodiversity too many babies 3 the scale of human life means we don t even see some problems a the slow soil erosion b the distant in time or place hazardous wastes starvation in Africa 4 risk perception minimizes some problems amp increases others a nuclear accidents and cancer are scary extinction isn t b reasons to not change may exceed concerns about significant risks staying in Centralia or living on a oodplain 5 the more people around the more reluctant we are to act as individuals lt s someone else s problem 6 we ll solve the easy obvious cheap annoying local problems rst How do we solve environmental problems 1 Understand what is particular about these problems a Limits to our understanding of global change 64digestfmmStern Paul C etal Global environmental change understanding the human dimension 1992 NationalAcademyPress The earth has entered a period hydrological climatological and biological change that differs from previous episodes ofglobal change in the extent to which it is ofhuman origin Human and environmental systems meet in two places where human actions proximately cause environmental change that is where they directly alter aspects of the environment and where environmental changes directly affect what humans value Humans threaten to alter the global climate by releasing socalled greenhouse gases CFCs already in the atmosphere are expected to cause significant reduction in stratospheric ozone over a period of several decades Course outline Geography 113 Spring 2008 37 Human activities are decreasing biological diversity on land in fresh waters and the seas in industrialized and developing nations from the coldest inhabited lands to the tropics Large physical and biological systems exhibit a number of characteristics that present a number of challenges to those endeavoring to understand them They require advances in scientific concepts theories and methods beyond those typical of existing disciplines Complex interdependencies exist both within and between environmental systems Changes in one part of the earth s environment can have effect in surprising places Global environmental systems frequently exhibit nonlinear responses Mathematical models ofglobalprocesses demonstrate that under certain conditions small perturbations in environmental systems can have large effects Environmental systems can undergo irreversible changes The clearest example is the extinction of species Long lag times are common in environmental systems CFCs released into the atmosphere migrate into the stratosphere where they are broken down by sunlight over aperiod of decades to centuries Global environmental changes can result from the interactions of local systems with each other and with largerscale systems Understanding of the biosphere may need to be built up from knowledge of smaller spatial scales such as ecosystems or biomes These characteristics of the global environmentpresent serious challenges for scientific research The nature of the global environment also raises doubts about the value of existing scientific disciplines for understanding global change 2 HUMANS AND ECOSYSTEMS Quotes are from G Tyler Miller a The ecosystem is not only more complex than we think it is more complex than we can ever think b Everything and everyone are all interconnected Function within the ecosystem with a sense of cooperation rather than domination c Everything we have has come from the earth or the sun We cannot sustain ourselves by depleting the earth s capital d We can never throw something away we can only through it somewhere else e The biotic potential is unlimited we can expand enough the exceed any limit f Higher levels of consumption create higher levels of trouble D What can a person do What is the nature of the problem 1 Engineering what technology would help Policy how do we help the common good Ethical why do people act as they do Research what do we know Educational what should others know 9919905quot Economic how can resources be available Course outline Geography 113 Spring 2008 7 Narrative how can people come to understand their world more clearly Ask whether we have the ethical framework to address the problems What rights do animals have What rights does a tree have How does Christianity regard the environment What do other peoples teach us about the world Are animals more important than the ecosystem they are in And then the politics in which realm environmental concerns on but one of the competing issues hunger fairness strategic and economic security must also win But that s another course
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