Environmental Science Chapter 6

In 2012

26 percent of world's population was under the age of 15 (29% in less developed, 16% in more developed)

2 Major problems hindering family planning

42 percent of all pregnancies are unwanted and 26 leads to abortions. Secondly, an estimated 215 mil couples in less developed countries want to limit their number of children and determine their spacing, but they lack access to family planning services.

Fact

42% of all pregnancies in less developed countries are unplanned. 26 ends in abortion.

Fact

95% of the 2.6 billion people projected to be born between 2012 and 2050 will be born in the less developed countries

Fertility rate

A measure of how many children are born in a population over a set period of time. There are two two types of fertility rates. The first is replacement-level fertility rate. The second type of fertility rate is total fertility rate.

Fact

A number of studies show that women tend to have fewer children if they are educated, have the ability to control their own fertility, earn an income of their own, and live in societies that do not suppress their rights.

Fact

A population with a large percentage of its people younger than the age of 15 will experience a rapid population growth unless death rates rise sharply. Cuz of this demographic momentum, the number of births in such a country would rise for several decades, due to a large number of girls entering their prime reproductive years.

Fact

As human pop grows so does the total human ecological footprint, which causes a higher overall impact on the earth's natural capital .

Fact

As the percentage of people age 65 or older increases, more countries will begin experiencing population declines. If population decline is gradual, its harmful effects can usually be handled.

Demographic transition

Demographers found that by looking at western euro countries that became industrialized in the nineteenth century. This states that as countries become industrialized and economically developed, their populations tend to grow more slowly. This takes place in four stages. Analysts believe that most of the world's less developed countries will make this over the next few decades . This will be cuz of newer technology. The four stages are preindustrial, transitional, industrial, and postindustrial. Other analysts fear that some countries will be stuck in the transitional stage.

Crude Birth Rate

Demographers use this. The number of live births per 1,000 people in a population in a given year.

Fact

Estimates of global human population in 2050 is from 7.8 to 10.8 billion people. Medium project of 9.6 billion people. By 2100, size between 8-16 billion people.

Fact

Factors that affect a countries average birth rate and total fertility rate Importance of children as a part of the labor force- causes many poor families to have a lotta kids. they need help with stuff. The cost of raising and educating children- is more costly in more developed nations because the children do not work until later in age. Many children in poor countries receive little education and have to work to help their families survive. The availability or lack of private and public pension systems- It can influence the decision on couples on how many kids to have. Pensions reduce a couples need to have several chidlren to help support them in old age. Infant deaths- More in poorer countries. This has affected the cultural norms related to family size in these countries. The more kids they have the more odds some will survive Urbanization- it plays a role in birth rate trends . People in urban areas have better access to family planning services and tend to have fewer children than do those living in the rural areas of poorer countries. Educational and Employment opportunities available for women- fertility rates tend to be low when woman have access to education and paid employment outside of the house. Educated woman tend to marry longer and have fewer children. Average Age at marriage- the age at which a woman has her first child. Women have fewer children when their average age at marriage is 25. Availability of legal abortions and the availability of reliable birth control methods allows women to control the number and spacing of children that they have Religious beliefs, traditions, and cultural norms

What Demographers Secondly Understand

Human population growth is unevenly distributed and this pattern is expected to continue. 2% of the 84 million new people were from more developed countries. Population is growing exponentially in developed countries by .1. The other 98% from less developed countries where the pop is growing 1.4 each year

What Demographers thirdly understand

Human population is moving from rural areas to cities. More than half of the world's population live in cities and their surrounding suburbs. Large majority of the city dwellers live in less developed countries.

Fact

Human populations grow or decline in particular countries, cities, or other areas through three factors: births, deaths, and migration

Fact

In many less-developed countries, the total fertility and population growth rates tend to be high, and large numbers of poor people are increasingly being crowed into unsanitary and difficult living conditions in slums and shantytowns.

Baby boom

It happened during the high birth rates between 1946 and 1964 in the US. This lead to 79 million million people being added to the US population.

Life expectancy

It is a useful indicator of the overall health of people in a country or region. It is the average number of years a person born in that year can be expected to live.

Population change

It is calculated by subtracting the number of people leaving a population from the number of people entering it during a specified time period

Age structure diagram

It is constructed by plotting the percentages or numbers of males and females in the total population in each of three age categories: pre reproductive (ages 0-14), reproductive ages (15-44), post reproductive (ages 45 and older),

Total fertility rate

It is the key factor affecting human population growth and size. The average number of children born to women in a population during their reproductive years.

Family planning

It provides educational and clinical services that help couples choose how many children to have and when to have them. Most of them provide info on birth spacing, birth control, and health care for pregnant women and infants. It has been a major factor in reducing the number of births throughout most of the world. It has reduced the amount of abortions performed each year and has decreased the number of mothers and fetuses dying during pregnancy. Studies have shown that this is responsible for a drop of at least 55 percent in total fertility rates. It saves 10-16 dollars cuz of unwanted births.

Fact

Japan, Germany, and Italy they have the largest percentage of old people. This shows that the number of working adults is shrinking in proportion to the number of seniors, which in turn is slowing the growth of tax revenues in these countries. How will the seniors be supported?

Three factors of population change

Life expectancy, infant mortality rate, migration

Fact

Scientific studies and experience has shown that the three most effective ways to slow or stop population growth are to reduce poverty, primarily through economic development and universal primary education; to elevate the status of women; and to to encourage family planning and reproductive health care.

Replacement-level fertility rate

The average number of children that couples in a population must bear to replace themselves. It is slightly higher than two children per couple. Higher in less developed countries. It is slightly higher than the two children because some children die before reaching reproductive years. Any fertility rate above this will cause a population to grow. The number of future parents alive has grown drastically.

Fact

The dramatic differences in population age structure between less-developed and more-developed countries show why most future human pop growth will take place in less developed countries

Fact

The environmental impact of a population is obtain by multiplying the effects of three factors: population size, affluence, and technology

Fact

The global population of seniors, is projected to triple by 2050, when one of every six people will be a senior. This graying of the world's population is largely due to declining birth rates and medical advances that have extended life spans.

Infant Mortality Rate

The number of babies out of every 1,000 born who die before their first day. It is viewed as one of the best measures of a society's quality of life because it reflects a country's general level of nutrition and health care. A high infant mortality rate reveals insufficient food, poor nutrition, and a high incidence of infectious diseases. This affects the total fertility rate. This is because women tend to have fewer children because fewer of their children die at a younger age in more affluent areas. These rates have declined since 1965. more than four million infants die of preventable causes during their first year of life. In 1900 the US infant mortality rate was 165. In 2012 it was 6.

Age structure

The number of percentages of males and females in young, middle, and older age groups in that population

Fact

The rapid growth of the world's population over the past 100 years is not primarily the result of a rise in birth rate but rather declining death rates. Due to people living longer and less infants dying. Less infants are dying because of increased food supplies, improvements in food distribution, better nutrition, medical advances such as immunizations and antibiotics, better sanitation, and safer water supplies.

Fact

The varying estimate of environmental refugees depends mostly on TFR projections. However, demographers have to make assumptions about death rates, migration, and a number of other variables.

By 2025

The worlds current pop of 1.5 bil people under 15 will enter prime reproductive years.

Fact

There are 40 mil envrionmental refugees, people who had to leave their homes because of water of food shortages, soil erosion, or some other form of envrionmental degradation of depletion. By 2020, 50 mil there'll be.

Fact

There were dramatic increases in per capita resource use and a much larger total and per capital ecological footprint in the 20th century

Women

They do almost of all of the world's domestic work and children care for little or no pay and provide unpaid health care than do all of the world's organized health-care services combined. In Africa, Asia, and Latin America - Women do 60-80 percent of work associated with growing food, gathering, and hauling wood and animal dung for use as fuel - They account for 60% of all hours worked - They receive only 10 percent of the world's income - They own 2% of the worlds land - They make up 70% of the world's poor - They make up 66% of the 800 mill illiterates in the world - 900 mil girls don't attend school - Poor women who can't read have 5-7 children, compared to the two or fewer children in societies were almost all women can read An increasing number of women in less developed countries are taking charge of their lives and reproductive behavior - This will play an important role in stabilizing pops, reducing poverty and environmental degradation, and allowing more access to basic human rights

What Demographers firstly understand

They recognize that the rate of population growth has slowed but the world's population is still growing gat a rate of about 1.2%. May not seem like a lot but 84 million added to world in 2012.

Baby boom

changes in the distribution of a country's age groups have long-lasting economic and social impacts. It added 79 million people to the US population between 1946 and 1964. The baby boom generation strongly influenced the US economy because they make up 36% of all adult americans. Since 2011, the number of Americans older than the age of 65 has grown at the rate of 10000 a day. This process has been called the graying of America.

Demographers

population experts. They recognize three important growth trends.

Factors that can hinder demographic transition are

rapid pop growth, extreme poverty, increasing environmental degradation and resource depletion. Another factor is that economic assistance from better developed countries has decreased since 1985. This shortage of funds to the poorer countries, plus the poor economies can keep large numbers of people trapped in poverty which could keep population growth rates high in such countries.

Cultural carrying capacity

the maximum number of people who could live in reasonable freedom and comfort indefinitely, without decreasing the ability of the earth to sustain future generations.

Crude death rate

the number of deaths per 1,000 people in a population in a given year.

Migration

the third factor in population change. It is the movement of people into and out of specific geographic areas. Reasons to move: jobs, economic improvement, religious persecution, ethnic conflicts, political oppression, or war

Fact

women make up roughly half of the world's population