Human Population Growth and the Green Revolution

Chapter 8
China’s One-Child Policy- In 1970, chinas 790 million people face starvation
The gov instituted a one child policy -china’s growth rate plummeted -In 1984, the policy exempted ethnic minorities and farmers
Unintended consequences: killing female infants and a black-market trade in teenage girls

Human Population Growth- 7 billion- population continue to rise in most countries particularly in poverty stricken developing nations -although the rate of growth is slowing, we are still increasing in absolute numbers -took all of human history to reach 1 bill in 1930, 130 years later, we reached 2 billion, and added the most recent billion in 12 years. -the population will double every 58 years -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 are irreplaceable
-Quality of life will suffer with unchecked growth Less food space and wealth per person
Population growth is correlated with poverty, not wealth
Policy makers believe growth increases economic, political, military strength
-they offer incentives for more children
-67% of European nations think their birth rates are too low
-in non eutopean nations 49% feel their birth rates are too high
IPAT model- I=P x A x T x S
Our total impact (I) on the enviorment 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
Demography-the application of population ecology to the study of humans (study pop size, density, distribution, age structure, sex ratio, birth, death, immigration, emigration, etc
Total Fertility Rate (TFR)- the average number of children born per female
Life Expectancy- average number of years that an individual is likely to continue to live. Increased because of urbanization, industrialization, person wealth, reduced infant mortality
Demographic Transition-a model of economic and cultural change to explain the declining death and birth rates in industrializing nations -stable preindustrial state of high birth and death rates change to a stable post-industrial state of low birth and death rates
Demographic Stages:
Pre Industrial Stage- birth and death rates are high
Transitional Stage- death rate declines due to increased food production and improved medical care
Industrial Stage- Birth rate declines due to increased opportunities for women and access to birth control
Post Industrial Stage- Birth and death rates are low
Is it universal?
Has occurred in Europe, U.S., Canada, Japan, etc. does not apply to all developing nations, the transition could fail in cultures. That place greater value on childbirth or grant women fewer freedoms
Empowering Women and How it affects growth rates- women lack the info and personal freedom to achieve equal power with men. 2/3 of people who cannot read, and 60% of those living in poverty are women. Providing info on incentives, education, contraception, and reproductive health care this will lower population growth rates.
Sex Ratios- naturally occurring sex ratios for humans slightly favors males (100 female vs 106 males)
Factors affecting population growth- rates of birth, death, and migration
Birth and immigration add individuals
Death and emigration remove individuals
Immigration and Emigration- refugees flee their home country as a result of war, civil strife, and enviormental degradation. -25 mill escape poor environmental conditions -movement causes environmental problems with no incentives to converse resources
Falling rates of growth only means the rate of increase is slowing not that population is falling
Wealth Gap- richest 20% use 86% of the world’s resources leaving 14% of resources for 80% of population
Poor countries have a higher growth rate cause there is no contraceptive use
HIV/AIDS impacts on Africa and demographic effects- 40 million people infected and 27 million live in sub Saharan Africa. Low rates of contraceptive use spread the disease, 1/5 south Africans are infected
6000 africans die each day,
-increased infant mortality,
-life expectancy fell from 59 to 40,
-millions of orphans created
Young, productive people die
-communities break down
-income and food production decline
-medical expenses and debt skyrocket
Demographic Fatigue-gov. face overwhelming challenges related to pop growth
Gov. are stretched beyond their capabilities and problems grow worse

If nations in Africa don’t take aggressive steps soon these countries will have rising death rates and increased birth rates and it will have a profoundly negative outcome for humans and the environment
The International Conference on Population and Development- In 1994 Cairo, Egypt, 179 nations called on all governments to offer universal access to reproductive health care within 20 years -offer better education and health care and alleviate poverty, disease, and sexism
Despite the success of family planning, recent republican administrations in the U.S. have declined to fund family-planning efforts -George W. Bush cancelled funding as one of his first acts on becoming U.S. president in 2001
Correlation Between Poverty and Population Growth- 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 born will be born in a poor regions that aren’t able to support them

Chapter 10
Oaxaca, Mexico Case Study With Maize- Corn originated in Oaxaca, mexico, 5.5k years ago
-2001 genes from genetically modified corn appeared in oaxacan maize
-Theses transegenes came from U.S. corn shipments
-Could contaminate native crops
-The genes did not appear in subsequent tests
Food production currently exceeds population growth
We produce food through technology -fossil fuels, irrigation, fertilizer, pesticides, cross breeding
Predictions of mass starvation in 1960s did not happen
Food Security- the guarantee of adequate and reliable food supply to all people at all times
-fewer people today are hunry than in 1970
-we have reduced hunger by half since 1970 but 850 million people still go hungry
Undernourishment-people receive less than 90% of their daily caloric needs -mainly from economic reasons in developing countries -31 million Americans are food insecure
Overnutrition- receiving too many calories
-25% of Americans are obese
-worldwide, 300 million people are obese
Malnutrition-shortage of nutrients the body needs
-the diet lacks adequate vitamins and minerals
Green Revolution- dramatically increased per acre yields, spread to the developing world in the 1940s with wheat, rice, and corn
Largely due to synthetic fertilizers, chemical pesticides, irrigation, and heavy equipment
From 1900-2000 cultivated area increased 33% while energy inputs increased 80 times
Positive effects on natural resources-prevented some deforestation and preserved biodiversity
Negative effects on natural resources-pollution, erosion, salinization, and desertification
Monoculture-a large expanse of a single crop
More efficient, increases output, but devastates biodiversity and is susceptible to disease and pests. Narrows human diet 90% of our food comes from 15 crop species and 8 livestock species
Pest-any organism that damages valuable crops
Weed-any plant that competes with crops
Pesticides-poisons that target pest organisms
-Insecticides-target insects
-Herbicides-target plants
-Fungicides-target fungi
400mill kg of pesticides are applied each year in us, 75% is applied to agricultural land, usage is increasing in developing countries
Resistance to Pesticides- some individuals are genetically immune to a pesticide and they survive and pass these genes to their offspring
Pesticides stop being effective which sparks the evolutionary arms race
Evolutionary Arms Race-Chemists increase chemical toxicity to compete with resistant pests but then pests respond by becoming more and more immune
Biological Control-uses a pests natural predators to control the pest, it reduces pest populations without chemicals, cactus moths control prickly pear.
The bacillus thuringienses (BT) is a soild bacteria that kills many pests
Integrated Pest Management (IPM)-IPM uses multiple techniques to suppress pests: biocontrol, chemicals, population monitoring, habitat alteration, crop rotation, transgenic crops, alternative tillage methods, and mechanical pest removal.
Within 4 years of using IPM in Indonesia, rice yields rose 13% and 179 million saved by phasing out subsidies
Genetic Engineering- laboratory manipulation of genetic material
Genetically modified organisms- organisms that have been genetically engineered by scientists
Recombinant DNA-DNA created from multiple organisms
Biotechnology- the material application of biological science to create products derived from organisms
Transgenic organism-an organism that contains DNA from another species
Transgenes- the genes that have moved between organisms
Pros of GM Crops-proponents say GM crops are safe, big business, benefit the enviorment by using less herbicides, reduce carbon emissions by needing fewer tractors and reduce no till farming
Impanct of GM Crops-dangerous to human health, escaping transgenes could pollute ecosystems and damage nontarget organisms, pests could evolve resistance, could ruin the integrity of native ancestral races, interbreed wit hclosey related wild plants
Cons of GM Crops-.take away business from small farmers, increasing use people are forced to use GM crops, research is funded by corporations that will profit if GM foods are approved
Different Nations View on GM Crops- Europe opposes GM foods, US has sued the European Union before the World Trade Organization, charging that the European Union was hindering free trade. Brazil, India, and China approve GM crops. Zambia refused US food aid because it was GM food
Preserving crop diversity- protects against crop failure, lost a great deal of genetic diversity in crops already, market forces discourage diversity in food appearance.
Seed Banks- institutions that preserve seed types as a kind of living museum of genetic diversity
Impact of Eating Animal Products-wealth and commerce increase so do consumption of meat, milk and eggs. Global meat production has increased five fold, per capita meat consumption has doubled.
Feedlot Agriculture-huge warehouses or pens designed to deliver energy rich food to animals living at high densities, over ½ worlds pork and poultry come from feedlots
Energy Choices through food choices- 90% of energy is lost every time energy moves from one trophic level to the next. The lower on the food chain from which we take our food sources the more people the earth can support. Some animals convert grain into meat more efficiently than others.
Enviormental Ramifications of Eating Meat-land and water are needed to raise food for livestock, producing eggs and chicken meat requires least space and water, producing beef requires the most
Aquacultures-raising aquatic organisms for food in controlled environment -Benefits:reliable protein source, sustainable, reduces fishing pressure on overharvested wild fish, energy efficient -Drawbacks:diseases can occur requiring expensive antibiotics, reduces food security, large amounts of waste, and farmed fish may escape bringing diseases into the wild.
Sustainable Agriculture- does not deplete soil, pollute water, or decrease genetic diversity.
Low input agriculture- uses smaller amounts of pesticide fertilizers growth hormons water and fossil fuel energy than industrial agriculture
Organic agriculture- uses no synthetic fertilizers, insecticides, fungicides, or herbicides. -Successes- sales have increased for them, lower iput costs, higher value for them, reduced pollution and chemical costs,