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Day 5. 6- 1. Housekeeping Items. A reminder that the meeting to protect Linley Valley West is on for tonight at 7:00 at the Kin Hut in Departure Bay. The bulldozers have already started to roll…. Housekeeping Items.
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Day 5 6-1
Housekeeping Items • A reminder that the meeting to protect Linley Valley West is on for tonight at 7:00 at the Kin Hut in Departure Bay. The bulldozers have already started to roll….
Housekeeping Items • If you have questions about your outlines, talk to me this week, if possible, as I will be away next week. • I apologize for the abrupt transition last class. The film clip was to prepare us for the topic today: population. • I will go over some of the slides today and would suggest you read the rest on your own. • We’re going to do something a little different today. Rather than me drone on and do all the work with some help from Ian, Chelsea, and Seamus, I’m going to make you do some work today.
Upon successfully completing this chapter, you will be able to • Assess the scope and historical patterns of human population growth • Evaluate how human population, affluence and technology affect the environment • Explain and apply the fundamentals concepts of demography • Outline the concept of demographic transition • Describe how wealth and poverty, the status of women, and family planning affect population growth • Link population goals to sustainable development
Central Case: China’s one-child policy • In 1970, the government instituted a one-child policy, drastically decreasing the growth rate (now 0.5%) • Unintended consequences: • Killing female infants • Unbalanced sex ratio • Black-market trade in teenage girls “As you improve health in a society, population growth goes down. You know. I thought it was…before I learned about it, I thought it was paradoxical.” – Bill Gates, Microsoft Corp.
Human population: is now 7 billion and growing • Populations continue to rise in most countries • Particularly in developing nations • Although the rate of growth is slowing, we are still increasing in absolute numbers • How much is 7 billion? • It would take 30 years, counting once each second, to reach 1 billion
The human population is growing nearly as fast as ever • It took all of human history- after 1880 - to reach 1 billion • In 1927 we reached 2 billion, and added the most recent billion in 12 years
The human population is growing nearly as fast as ever (cont’d) • At today’s 2.1% annual growth rate, the population will double in 33 years • If China’s rate had continued at 2.8%, it would have had 2 billion people in 2004.
Perspectives on human population have changed over time • 1700s – more children meant better support in old age and more labour for factory work • 1766: Thomas Malthus – growing population is eventually checked by limits on births or increases in deaths • 1968: Paul Ehrlich – population is growing too fast and must be controlled • Disastrous effects on the environment and human welfare
Perspectives on human population have changed over time (cont’d) • Ehrlich and other neo-Malthusians have argued that population is growing much faster than our ability to produce and distribute food and that population control is the only way to prevent: • Massive starvation • Environmental degradation • Civil strife
Is population growth really a “problem” today? • Population growth results from technology, sanitation, food • Death rates drop, but not birth rates • Some people say growth is no problem • New resources will replace depleted ones • But, some resources (i.e., biodiversity, a balanced climate) are irreplaceable • Quality of life will suffer with unchecked growth • Less food, space, wealth per person
Is population growth really a “problem” today (cont’d)? • Sheldon Richman – humans find potential stuff and human intelligence turns it into resources • Humankind will always be able to save itself with a “technological fix” • Yet not all resources can be replaced or reinvented once they are depleted (e.g. extinct species, land) • Population growth is much more strongly correlated with poverty than with wealth
Is population growth really a “problem” today (cont’d)? • Policymakers believe growth increases economic, political, military strength • They offer incentives for more children • 49% of European nations think their birth rates are too low • In non-European nations, only 12% feel their birth rates are too low
The Science Behind the Story • Mapping Our Population’s Environmental Impact • Burgeoning numbers of people are making heavy demands on Earth’s natural resources and ecosystem services • Humans are responsible for using up almost 24% of the planet’s NPP • Direct harvesting of crops, timber, etc. account for most of this • Densely populated and heavily farmed regions such as India, Eastern China, and Europe show the greatest proportional use of NPP 6-16
Population is one of several factors that affect the environment • The IPAT model: I = P x A x T x S • Our total impact (I) on the environment results from the interaction of population (P), affluence (A) and technology (T), with an added sensitivity (S) factor • Population = individuals need space and resources • Affluence = greater per capita resource use • Technology = increased exploitation of resources • Sensitivity = how sensitive an area is to human pressure
Population is one of several factors that affect the environment (cont’d) • Status quo leads to • Sudden food & population decrease • Pollution increase • Sustainability leads to • Food & population stabilize • Pollution decrease
The environment has a carrying capacity for humans • Demography: the application of population ecology principles to the study of statistical change in human populations • Environmental factors set limits on our population growth, and the environment has a carrying capacity for our species • Four significant periods of societal change appear to have fundamentally altered the human relationship with the environment
The environment has a carrying capacity for humans (cont’d) • Paleolithic period (Old Stone Age): • Use of fire as much as 1.5 million years ago • Shape and use of stones 2.5 million years ago, which helped modify their environment • Little evidence about world populations at this time FIGURE 6.7
The environment has a carrying capacity for humans (cont’d) • Neolithic (New Stone Age): • Agricultural Revolution • 10,000 to 12,000 years ago • Initiated a permanent change in the way humans relate to the natural environment • Made cities, trades, science, armies, and other aspects of modern culture possible FIGURE 6.7
The environment has a carrying capacity for humans (cont’d) • Industrial Revolution: • Began in the mid – 1700s • A shift from rural life, animal-powered agriculture, and manufacturing by craftsmen, to an urban society powered by fossil fuels • Improvements in sanitation and medical technology • Enhanced agricultural production FIGURE 6.7
The environment has a carrying capacity for humans (cont’d) • Medical-Technological Revolution: • Currently in the midst modern medical and technological advancements • People live longer and healthier lives • Green Revolution – shift to modern agricultural practices FIGURE 6.7
Demography is the study of human population • Demographers study: • Population size • Density • Distribution • Age structure • Sex ratio • Rates of birth, death, immigration, and emigration
Demography is the study of human population (cont’d) • Population size - only one factor and does not tell the whole story • A population’s environmental impact depends on its density, distribution, and composition, as well as affluence, technology, and level of consumption
Demography is the study of human population (cont’d) • Humans are unevenly distributed around the globe • Highest population density is in temperate, subtropical, and tropical climates • Unpopulated areas tend to be environmentally sensitive (high S value in the IPAT equation)
Demography is the study of human population (cont’d) • Age structure important in predicting future dynamics of populations • Having many individuals in young age groups results in high reproduction and rapid population growth
China’s reproductive policy Consider the benefits as well as the problems associated with a reproductive policy such as China’s. Should a government be able to enforce strict penalties for citizens who fail to abide by such a policy? What alternatives can you suggest for dealing with the resource demands of a quickly growing population? weighingtheissues
Demography is the study of human population (cont’d) • Sex Ratios can affect population dynamics • Naturally occurring sex ratios for humans slightly favour males (100 females born to 106 males) • In China, 120 boys were reported for 100 girls • Cultural gender preferences, combined with the government’s one-child policy, led to selective abortion of female fetuses • Had the undesirable social consequences of many single Chinese men • Teenage girls were kidnapped and sold as brides
Population change results from birth, death, immigration, and emigration • Whether a population grows, shrinks, or remains stable depends on: • Rates of birth, death, and migration • Birth and immigration add individuals • Death and emigration remove individuals • Crude birth rate (nativity or natality) = number of births per 1000 individuals • Crude death rate (mortality) = number of deaths per 1000 individuals
Population change results from birth, death, immigration, and emigration • Technological advances led to dramatic decline in human death rates widening the gap between crude birth rates and crude death rates and resulting in population expansion • Growth rates in many countries have been declining, even without population control policies • Decline due in part from a steep drop in birth rates
Population change results from birth, death, immigration, and emigration
Total fertility rate influences population growth • Total fertility rate (TFR) = average number of children born per female member of a population during her lifetime • Replacement fertility = the TFR that keeps the size of a population stable
Total fertility rate influences population growth (cont’d) • Increasing urbanization decreases TFR • Children go to school, and increase costs • With social security, elderly parents need fewer children to support them • Greater education allows women to enter the labor force, with less emphasis on child rearing
Consequences of low fertility? In Canada, the United States, and every European nation, the total fertility rate has now dipped below replacement fertility rate. What economic, social, or environmental consequences – positive or negative – do you think might result from below-replacement fertility rates? weighingtheissues
Some nations have experienced the demographic transition • Natural rate of population change = due to birth and death rates alone • In countries with good sanitation, health care, and food, people live longer • Life expectancy = average number of years that an individual is likely to continue to live • Increased due to reduced rates of infant mortality • Urbanization, industrialization, and personal wealth
Some nations have experienced the demographic transition (cont’d) • Demographic transition = a model of economic and cultural change to explain the declining death and birth rates in industrializing nations • high birth and death rates change to low birth and death rates • As mortality decreases, there is less need for large families • Parents invest in quality of life
Some nations have experienced the demographic transition (cont’d) Population growth is seen as a temporary phenomenon
Is the demographic transition a universal process? • It has occurred in Europe, U.S., Canada, Japan, and other nations over the past 200-300 years • But, it may or may not apply to all developing nations • The transition could fail in cultures that • Place greater value on childbirth • Grant women fewer freedoms For people to attain the material standard of living of North Americans, we would need the natural resources of four and a half more Earths
The status of women greatly affects population growth rates • 2010: 55% of married women (aged 15-49) worldwide reported using modern contraception to plan / prevent pregnancy • Social empowerment of women reduces unintended pregnancy • Increasing female literacy is strongly associated with reduced birth rates
The status of women greatly affects population growth rates (cont’d) Increasing female literacy is strongly associated with reduced birth rates in many nations
Small Group Exercise • I will break you into five groups: Japan, India, China, North America, and Sub-Saharan Africa. Your goal will be to answer the following questions: • What is the population-related problem (or problems)? • What is one or more potential solution or solution that has already been tried? • What are some actual or possible unintended negative side-effects? • Is there any way of off-setting them? • What are the long-term prospects for your country or region, with intervention or leaving things as they are?
Population policies and family-planning programs are working • These policies lower population growth rates in all types of nations • Programs for population control: • India – incentives for a “two-child norm” • Thailand – family planning education and increased availability of contraceptives • 1994: U.N. platform for governments to offer universal access to reproductive health care within 20 years.
Population policies and family-planning programs are working (cont’d) Blue = family planning accessible Red = family planning not accessible
Poorer societies have higher growth rates than wealthier societies Consistent with the demographic transition theory They have higher fertility and growth rates, with lower contraceptive use 99% of the next billion people added will be born in poor, less developed regions that are least able to support them Poverty often results in environmental degradation (e.g. soil degradation, hunting of large mammals) Poverty is strongly correlated with population growth
Consumption from affluence creates environmental impacts • Affluent societies have enormous resource consumption and waste production • People use resources from other areas, as well as from their own • Individuals’ ecological footprints are huge • The addition of 1 Canadian to the world has as much environmental impact as 6 Chinese, or 12 Indians or Ethiopians, or 40 Somalians.
Consumption from affluence creates environmental impacts (cont’d) Humanity’s global ecological footprint surpassed Earth’s capacity to support us in 1987