POPULATION GROWTH AND VARIATIONS AMONG NATIONS
There are 5 main concepts that our students struggle with when learning about population growth and the relationship of population to geological resource use:
1. overpopulation is a leading environmental problem,
2. exponential population growth and development leads to faster depletion of resources,
3. population grows exponentially,
4. why population prediction is difficult,
5. population is not evenly distributed throughout the world.
A leading environmental problem: Overpopulation
Students do not understand that overpopulation is the cause of many other environmental problems. To help students understand this, one of my colleagues asks her students to list three important local and global environmental issues as part of a survey on the first day of class. During this lecture, we will present overpopulation as the top environmental problem:
1. Pollution (unspecified):14.7%
2. Global warming:14.5%
3. Air pollution:13.5%
4. Habitat destruction:13.1%
5. Resource depletion/degradation:11.8%
6. Population growth/Overpopulation:7.9%
7. Natural disasters:6.2%
8. Water pollution:6.6%
9. fossil fuels (oil spills/ANWR):6.0%
10. Waste management:3.5%
11. Miscellaneous (famine, poverty, ignorance, etc):2.3%
How many of these problems are the direct or indirect result of overpopulation? Would we have such a problem with the top three – pollution, global warming and habitat- if world population was not so large? Other than some of the natural disasters, most of these other environmental problems are due to overpopulation.
More people = More babies
Students may have a hard time understanding that population growth is controlled not only by birth and death rates but also by the present population. The mathematics of exponential growth govern the prediction of population growth. In some cases, you may want to point out that students may have heard of exponential growth in other contexts, such as compound interest or the spread of viral disease. The rate of population growth at any given time can be written:
where
N0 is the starting population;N is the population after a certain time, t , has elapsed,
r is the rate of natural increase expressed as a percentage (birth rate - death rate) and e is the constant 2.71828... (the base of natural logarithms).
A plot of this equation looks something like the plot on the right. Population grows exponentially - if the rate of natural increase (r) doesn't change. The variable r is controlled by human behavior as described below.
Essential to understanding the mathematics of population growth is the concept of doubling time. Doubling time is the time it takes for population to double and it is related to the rate of growth. When the population doubles, N = 2N0. Thus the equation becomes
ln 2/r = t
or 0.69/r = t; where r is the rate and t is the doubling time.
In many ways, it is similar to half-life. But instead of the time it takes for half the isotopes to decay, it is the time it takes for a known quantity to double.
"Birth control" was advanced as alternative to the then-fashionable terms "family limitation" and "voluntary motherhood." Family limitation referred to deliberate attempts by couples to end childbearing after the desired number of children had been born. Voluntary motherhood had been coined by feminists in the 1870s as a political critique of "involuntary motherhood" and expressing a desire for women's emancipation. Advocates for voluntary motherhood disapproved of contraception, arguing that women should only engage in sex for the purpose of procreation and advocated for periodic or permanent abstinence. In contrast the birth control movement advocated for contraception so as to permit sexual intercourse as desired without the risk of pregnancy. By emphasising "control" the birth control movement argued that women should have control over their reproduction and the movement had close ties to the feminist movement. Slogans such as "control over our own bodies" criticised male domination and demanded women's liberation, a connotation that is absent from family planning, population control and eugenics. Though in the 1980s birth control and population control organisations co-operated in demanding rights to contraception and abortion, with an increasing emphasis on "choice."
The societal acceptance of birth control required the separation of sex from procreation, making birth control a highly controversial subject in the 20th Century. Birth control has become a major theme in feminist politics who cited reproduction issues as examples of women's powerlessness to exercise their rights. In the 1960s and 1970s the birth control movement advocated for the legalisation of abortion and large scale education campaigns about contraception by governments. In a broader context birth control has become an arena for conflict between liberal and conservative values, raising questions about family, personal freedom, state intervention, religion in politics, sexual morality and social welfare.
The effectiveness of a birth control method is generally expressed by how many women become pregnant using the method in the first year of use. Thus, if 100 women use a method that has a 0 percent first-year failure rate, then 0 of the women should become pregnant during the first year of use. This equals 0 pregnancies per 100 woman-years, an alternative unit. Sometimes the effectiveness is expressed in lifetime failure rate, more commonly among methods with high effectiveness, such as vasectomy after the appropriate negative semen analysis.
The most effective methods in typical use are those that do not depend upon regular user action. Surgical sterilization, Depo-Provera, implants, and intrauterine devices (IUDs) all have first-year failure rates of less than one percent for perfect use. In reality, however, perfect use may not be the case, but still, sterilization, implants, and IUDs also have typical failure rates under one percent. The typical failure rate of Depo-Provera is disagreed upon, with figures ranging from less than one percent up to three percent.
Other methods may be highly effective if used consistently and correctly, but can have typical use first-year failure rates that are considerably higher due to incorrect or ineffective usage by the user. Hormonal contraceptive pills, patches or rings, fertility awareness methods, and the lactational amenorrhea method (LAM), if used strictly, have first-year (or for LAM, first-6-month) failure rates of less than 1%. In one survey, typical use first-year failure rates of hormonal contraceptive pills (and by extrapolation, patches or rings) were as high as five percent per year. Fertility awareness methods as a whole have typical use first-year failure rates as high as 25 percent per year; however, as stated above, perfect use of these methods reduces the first-year failure rate to less than 1%. Intrauterine devices (IUDs) were once associated with health risks, but most recent models of the IUD, including the ParaGard and Mirena, are both extremely safe and effective, and require very little maintenance. Condoms and cervical barriers such as the diaphragm have similar typical use first-year failure rates (14 and 20 percent, respectively), but perfect usage of the condom is more effective (three percent first-year failure vs six percent) and condoms have the additional feature of helping to prevent the spread of sexually transmitted diseases such as the HIV virus. The withdrawal method, if used consistently and correctly, has a first-year failure rate of four percent. Due to the difficulty of consistently using withdrawal correctly, it has a typical use first-year failure rate of 19 percent, and is not recommended by some medical professionals. Combining two birth control methods, can increase their effectiveness to 95% or more for less effective methods. Using condoms with another birth control method is also one of the recommended methods of reducing risk of getting sexually transmitted infections, including HIV. This approach is one of the dual protection strategies
The Growth of Human Population can be Viewed in the Following Four Major Periods or Stages
Stage 1. An early period of hunters and gatherers
This period ranges between the first evolutions of humans on this planet to the beginning of agriculture. During this period, it is estimated that the total population was probably less than a million, population density was about 1person per 130-260 sq km in the most habitable areas, and the average rate of growth was perhaps less than 0.00011% per year.
Stage 2. Early, per-industrial agriculture
This period began sometime between 9,000 BC and 6,000 BC and lasted approximately until the 16th century AD. The first major increase in population came during this period. The total human population of the world was approximately 100 million by 1AD that further increased to about 500 million by 1600 AD. The population density increased greatly to about 1 or 2 people per sq km or even more. The average rate of growth was probably about 0.03%.
Stage 3. The age of industrial revolution
The second and much more rapid increase in population started about 400 years ago with the industrial revolution associated with the advances in medicines and health care. Experts are of the opinion that Renaissance in Europe, (beginning about 1600 AD) marks the transition from agricultural to liberate societies, when medical care and sanitation were factors responsible in reducing the death rate. The total human population of about 900 million in 1800 AD almost doubled in the next century and again doubled to approximately 3 billion by 1960. The average rate of growth by 1600 AD was about 0.1% per year, which increased about one-tenth of a percent every 50 years until 1950. The main reasons of this rapid increase in population were discovery of the causes of diseases, invention of vaccines, improvement in sanitation, and advances in agriculture that led to a great increase in the production of food, shelter and clothing.
Stage 4. The modern era
Though the rate of population growth has slowed down in developed countries, but population still continues to increase rapidly in many parts of the world, particularly developing countries. At mid 2002, the world population stood at 6.215 billion. The average rate of growth reached 2% in the middle of the 20th century and has declined to 1.3% in 2002 AD. According to projections, the global population will be Approximately 8 billion by 2025 and 10 billion by 2050 AD.
According to World Bank projections, the world population may stabilize between 10.1 to 12.5 billions. Developed countries would only increase from 1.2 billion today to 1.9 billion, but developing countries would increase from 5 billion to 9.6 billion. In these projections, the developing countries using by 95%
Variation of Population Among Nations
The distribution of world population densities show that while the great majority of the land surface is sparsely or moderately populated, but some limited areas are densely populated. The densely populated areas include Western Europe, the Indian subcontinent, the plains and river valleys of China, and north-eastern USA. High concentrations of people are also found in some relatively smaller areas, for example—the Nile valley of Egypt, the Islands of Java in Indonesia and the Southern part of Japan.
In terms of continents and countries, the world’s population is very ill-balanced. More than half of the world’s people live in Asia (approximately 3.7 billion), which accounts for only one-fifth of the world’s land area; while North, Central and South America together occupying more than a quarter of the land surface, have only one-fifth of the population (1.3 billion). The African continent also accounts for a quarter of the land surface but has just over one-eighth (840 million) of the world population. On the other hand, Europe whose area is only one twenty-fifth of the total has about one-ninth (729 million) of the world’s people.
The distribution within the continents is also uneven. In Asia, China alone, with about 1.29 billion people, accounts for one-third Asian and one-fifth of the world population. The Indian subcontinent has a further 1.3 billion people—India, 1.05 billion; Pakistan, 143.5 million; Bangladesh, 133.6 million; Nepal , 23.9 million; Sri Lanka , 18.9 million; Bhutan, 0.9 million; and Maldives, 0.3 million. In Europe too, the population is an evenly distributed. Far less people live in Northern European countries than in other European countries .The most populous European countries are Russia (143.5 million), Germany (82.4 million), United Kingdom (60.2 million), France (59.5 million); Italy (58.1 million), Ukraine (48.2 million), Spain (41.3 million) and Poland (38.6 million). In Africa and Americas people are for the most part spread very thinly across the land, leaving large sections such as Northern Canada, Southwest USA, the Sahara desert and the Amazon forest practically uninhabited.
Factors discouraging settlement
They are usually climatic or relief factors. The main factors are—cold, altitude, heat, drought, poor soils, inaccessibility, etc.
Factors encouraging settlements
They are –good land, flat or undulating terrain, the existence of mineral resources, a good climate suitable for a wide range of crops or a less equable climate suitable to the cultivation of specialized crops which have a good market, etc. Other factors include extension of roads, railways and other modes of transportation.
Population Explosion
The rapid growth of population is perhaps the most obvious factor affecting the present and future national and regional development, but it is by no means the only population problem in the world today. The main problem is that of ‘Population Explosion’.
Population explosion doesn’t mean overpopulation or population density. Infact, overpopulation or population density is not the major problem. The problem arises when the economic developments fails to maintain pace with population growth. So the most important factors regarding population are how fast population is growing; and most important is where it is growing. For example, Japan has a high population density but it ranked first on the human development index formulated by U.N.D.P. On the other hand low population density areas of Africa or S. America are unable to support the existing population. Thus, the size, distribution and structure of the population within a country must be viewed in relation to its natural resources and the techniques of production used by its population. The extent to which they are used and the way in which they are utilized determine whether an area/country is under-or over-populated and hence witnessing population explosion or not. A country is said to have an “optimum population” so long as the number of people is in balance with the available resources of the country. If in a country the process of industrialization accompanied by urbanization is not fast and education is not widespread, then this is really a grave situation called as Population Explosion.
Effects of population explosion
The effect of population explosion is numerous with far reaching consequences. Some of them are enumerated as under:
· Unemployment,
· Low living standard of people,
· Hindrance in the process of development of economy
· Pressure on agriculture land,
· Low per capital income,
· Lack of basic amenities like water supply and sanitation, education, health, etc.,
· High crime rate
· Environmental damage,
· Migration to urban area in search of job,
· Energy crisis,
· Overcrowding of cities leading to development of slums.
Population explosion in Indian context
The population explosion, though a worldwide phenomenon, poses a serious threat to India as it has to maintain 16.9% of world’s population on only 2.4%of the world’s area. The present growth rate of 1.7% is much higher than the world population growth rate of 1.3%, which is of great concern.
In order to overcome this problem of population explosion, a sound Population Policy is required with the following objectives:
1. Quick economic development and raising the per capital income.
2. Significant reduction in birth rate, which is more fundamental and important than the first, by providing legal and fiscal motivations like raising age of marriage, legalization abortion etc.
3. The planning of population must not aim merely at controlling the rate of multiplication but it should also include the improvement of the quality of the population as well by providing better facilities in education, health, etc.
4. (iv) The death rate should be brought down further, as high death rate results in waste of human energy and resources.
5. Integrating population planning with economic planning.
We are thus facing a population explosion of crisis dimensions which has largely diluted the fruits of the remarkable economic progress that we have made over the last few decades. It is clear that simply to wait for education and economic development to bring about a desirable drop in fertility is not a practical solution. The time factor is so pressing and the population growth so formidable that we have to get out of this vicious circle through a direct assault upon the population problem as a national commitment.
Methods of birth control
The effectiveness of a birth control method is generally expressed by how many women become pregnant using the method in the first year of use. Thus, if 100 women use a method that has a 0 percent first-year failure rate, then 0 of the women should become pregnant during the first year of use. This equals 0 pregnancies per 100 woman-years, an alternative unit.
The most effective methods in typical use are those that do not depend upon regular user action.
a) Surgical sterilization, Depo-Provera, implants, and intrauterine devices (IUDs) all have first-year failure rates of less than one percent for perfect use. In reality, however, perfect use may not be the case, but still, sterilization, implants, and IUDs also have typical failure rates under one percent. The typical failure rate of Depo-Provera is disagreed upon, with figures ranging from less than one percent up to three percent.
b) Other methods may be highly effective if used consistently and correctly, but can have typical use first-year failure rates that are considerably higher due to incorrect or ineffective usage by the user. Hormonal contraceptive pills, patches or rings, fertility awareness methods, and the lactational amenorrhea method (LAM), if used strictly, have first-year (or for LAM, first-6-month) failure rates of less than 1%. In one survey, typical use first-year failure rates of hormonal contraceptive pills (and by extrapolation, patches or rings) were as high as five percent per year. Fertility awareness methods as a whole have typical use first-year failure rates as high as 25 percent per year; however, as stated above, perfect use of these methods reduces the first-year failure rate to less than 1%. Intrauterine devices (IUDs) were once associated with health risks, but most recent models of the IUD, including the ParaGard and Mirena, are both extremely safe and effective, and require very little maintenance.
c) Condoms and cervical barriers such as the diaphragm have similar typical use first-year failure rates (14 and 20 percent, respectively), but perfect usage of the condom is more effective (three percent first-year failure vs six percent) and condoms have the additional feature of helping to prevent the spread of sexually transmitted diseases such as the HIV virus. The withdrawal method, if used consistently and correctly, has a first-year failure rate of four percent. Due to the difficulty of consistently using withdrawal correctly, it has a typical use first-year failure rate of 19 percent, and is not recommended by some medical professionals.
d) Combining two birth control methods, can increase their effectiveness to 95% or more for less effective methods. Using condoms with another birth control method is also one of the recommended methods of reducing risk of getting sexually transmitted infections, including HIV. This approach is one of the dual protection strategies.
Aim of ‘Family Welfare Programme’
In the year 1952, India launched a nation-wide family planning programme making it the first country in the world to do so. Unfortunately, family planning in India is associated with numerous misconceptions—one of them is its strong association in the minds of people with sterilization, while others equate it with birth control. The recognisation of its ‘welfare concept’ came only when the family planning programme was named as ‘Family Welfare Programme’ in the year 1977. The concept of welfare is very comprehensive and is basically related to quality of life. The Family Welfare Programme aims at achieving a higher end- that is, to improve the quality of life of the people.
Although the performance of the programme was low during 1977-78, but it was a good year in the sense that it moved into new healthier directions. The 42nd Amendment of the Constitution has made “Population Control and Family Planning” a concurrent subject. The acceptance of the programme is now purely on voluntary basis. The launching of the Rural Health Scheme in 1977 and the involvement of the local people (e.g., trained Dais and Opinion leaders) in the family welfare programmes at the gross-root level were aimed at accelerating the pace of progress of the programme. India was a signatory to the Alma Ata Declaration, 1978. The acceptance of the primary health care approach to the achievement of ‘Health For All by 2000 AD’ led to the formulation of a ‘National Health Policy’ in 1982. The policy laid down the long-term demographic goal of Net Reproduction Rate (NRR)=1 by the year 2000-which implies a 2-child family norm-through the attainment of a birth rate of 21 and a death rate of 9 per thousand population, and a couple protection rate of 60% by the year 2000. The successive Five Year Plans were accordingly set to achieve these goals. The Government of India envolved a more detailed and comprehensive National Population Policy in 1986, to promote it on a voluntary basis as a ‘movement of the people, by the people, for the people’. It has given family planning the broadest possible dimensions which include not only health and family welfare but also child survival, women’s status and employment, literacy and education, socio-economic development and anti-poverty programmes.
The current approach in favour today is one of involvement and integration. The idea is to value those who stand to benefit from the programme and integrate the various attempts to propagate the same. Family Welfare Programme with such an approach can reduce the population growth to more manageable levels. Presently, the Family Welfare Programme seeks to promote on a voluntary basis, responsible and Planned Parenthood with one child norm, male or female, through independent choice of family welfare methods best suited to acceptors.
Problems of family welfare programme
The two major problem of Family Welfare Programme are:
1. Generally women are the major targets of family planning programmes .according to National Family Health Survey, the most widely used method of family planning in India is female sterilization. This shows that family planning has largely remained a women-centered programme. Due to reluctance of men to use permanent methods, women are forced to accept family planning methods. Gender specificity or gender subordination has to be eliminated in the approach in the family planning programmes as far as possible.
2. The imbalance in the sex ratio (female/1000 male) across the nation, which is 933, is another worrisome factor. In states like Haryana (SR=861), Punjab (SR=874), U.P. (S.R=898), Delhi (SR=821), Sikkim (SR=875) and others, the girl-child is being discriminated against even before birth. The instance of female infanticide in these and other states has brought down the sex ratio to an all time low. Though there is a law banning the determination of the sex of the child in the womb, unscrupulous medical practitioners and short-sighted parents connive to prevent the birth of female children. There is, thus, an urgent need to prevent the misuse of technology through education and awareness.