HUMAN POPULATION GROWTH Earth's population: 6 billion (Oct 12, 1999) Every second, five people are born and two people die, a net gain of three people.

Every day, +250,000 = 2 x Irvine This year, +87,000,000 = Mexico This decade +1,000,000,000 = China

Thomas Malthus (1798) “An Essay on the Principle of Population”

• Populations grow geometrically while supporting resources grow arithmetically • Population, if not purposefully checked (“preventative checks”), would outpace resources and lead to unplanned “positive checks” that would return population to sustainable levels

Crop Yield and Fertilizer Input

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“Green revolution”: high-yielding crop

• • • •

varieties chemical fertilizers pesticides irrigation mechanization Global Fertilizer use

Net primary productivity (NPP) and “Carrying Capacity”

(“How many People can the Earth Support?) •Prior to human impact, NPP was about 150 billion tons of organic matter per year. •Humans have destroyed about 12% of the terrestrial NPP, and use or co-opt additional 27%. •Thus we have already appropriated about 40% of the terrestrial food supply •If we appropriate ALL of the terrestrial food capacity, the planet could support 2.5 x 6 = 15 billion

Billions of people Global “Carrying Capacity”

Human dominance or alteration of several major components of the Earth system

• • transformed or degraded 39-50% of the Earth's land surface use 8% of the primary productivity of the oceans (25% for • • • • upwelling areas and 35% for temperate continental shelf areas).

increased atmospheric CO2 concentration by 30% use more than half of the accessible surface fresh water over 50% of terrestrial nitrogen fixation is caused by human activity on many islands, more than half of plant species have been • introduced by man; on continental areas the fraction is 20% or more about 20% of bird species have become extinct in the past 200 • years, almost all of them because of human activity 22% of marine fisheries are overexploited or depleted, 44% more are at the limit of exploitation

Coastal Zone Color Scanner Global chlorophyll NOVEMBER 1978 to JUNE 1986

The Global Biosphere (September 97 - August 98)

Upwelling off Cape Town, South Africa, 16 Sept. 1997

Chlorophyll West of Galapagos Islands Normal El Niño

Gulf of Mexico (23 February 1998)

POPULATION AND AVAILABILITY OF RENEWABLE RESOURCES

Population (millions) Fish Catch (million tons) Irrigated Land (million hectares) Cropland (million hectares) 1990 2010 Total Change (%) Per Capita Change (%) 5,290 7,030 85 102 33 20 -10 237 277 1,444 1,516 17 5 -12 -21 Rangeland and Pasture (million hectares) 3,402 3,540 4 -22 Forests (million hectares) 3,413 3,165 -7

Source: Postel, S. "Carrying capacity: Earth's bottom line." State of the World, 1994.

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Decline of Fisheries

Regional population patterns:

Population density

Consortium for International Earth Science Information Network.

POPULATION DENSITY AND GROWTH RATE

Region Asia Europe Africa Former Soviet Union Latin America North America Oceania Inhabitants /sq.km. agricultural land 423 213 80 69 58 55 15 % annual growth rate 1.8

0.2

3 0.7

1.9

0.7

1.4

DOUBLING TIMES

World Africa Kenya (fastest) Latin America Asia 40 years 23 years 20 years 30 years 36 years

The “demographic transition”

Reduction in childhood death rates

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DDT used against mosquitoes that transmit malaria

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Childhood immunization used against cholera, diphtheria, etc.

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Antibiotics used against bacterial infections

“Rate of Natural Increase”

“Rate of Natural Increase”

People over 100 years old in U.S.:

4,000 in 1970; 64,000 in 1990 projected 1.4 million in 2040

China

(20% of world’s population) "one-child-per-couple" policy since 1979:

•Rewards for having only one child: grants, additional maternity leave, increased land allocations. Children get preferential treatment in education, housing, and employment.

•Couples punished for refusing to terminate unapproved pregnancies, for giving birth when under the legal marriage age, and having an approved second child too soon. •Penalties include fines, loss of land grants, food, loans, farming supplies, benefits, jobs and discharge from the Communist Party. •In many provinces sterilization is required after the couple has had two children.

China’s Population Policy

Children per woman: 1970: 5.01

1995: 1.84

Population still growing!

Population in 2000: 1.3 billion Projected for 2025: 1.5 billion

Criticisms:

Use of abortion Forcible abortions and sterilization Infanticide

India

1998: 853 million. 2025 predicted: 2 billion

U.N. Conference on Population (Cairo, 1994) "Programme of Action" (182 nations) Goal: to stabilize human population at 7.8 billion by 2050 .

1. Provide universal access to family-planning and reproductive health programs.

2. Recognize that environmental protection and economic development are not necessarily antagonistic. Promote free trade, private investment and development assistance.

3. Make women equal participants in all aspects of society - by increasing women's health, education, and employment.

4. Increase access to education. Provide information and services for adolescents to prevent unwanted pregnancies, unsafe abortion, and the spread of AIDS and sexually transmitted diseases.

5. Ensure that men fulfill their responsibility to ensure healthy pregnancies, proper child care, promotion of women's worth and dignity, prevention of unwanted pregnancies, and prevention of the spread of AIDS and sexually transmitted diseases.

United Nations Population Fund (UNFPA)

Programs to improve:

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pre- and post-natal mother's health

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access to voluntary family planning programs and contraception

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STD and HIV education and prevention

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U.S. funding withheld for many years because of UNFPA’s support of China’s policies

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U.S. funding restored for F.Y. 2000 at level of $25 million

International Planned Parenthood Federation (IPPF)

1. To meet the demand and unmet need for quality services; 2. To promote sexual and reproductive health for all; 3. To eliminate unsafe abortion; 4. To take affirmative action to gain equity, equality and empowerment for women; 5. To help young people understand their sexuality and to provide services that meet their demands; 6. To maintain the highest standards of care throughout the Federation.