Unit 5
Human population and the environment
There is strong evidence that the growth of the world population poses serious threats to human health, socioeconomic development and the environment. It has taken only 12 years for the world population to grow from 5 billion to today's 6 billion. This is the shortest time ever to add 1 billion people — a number equivalent to the population of India or the combined population of the United States and Europe.
Some 10 000 years ago, when only about 5 million people inhabited the Earth, few biological systems were seriously damaged by human activity. Today, however, the world faces an environmental dilemma. Current demands are depleting many of the Earth's natural resources and ecological services. Within the next 50 years, it is likely that those life-supporting systems will somehow have to accommodate 3 billion more people as well as support desperately needed advances in living standards for those in poverty, particularly the 3 billion people now living on about $2 a day.
The impact of humans on their environment is related to population size, per capita consumption and the environmental damage caused by the technology used to produce what is consumed. The exploitation of technology and the high consumption pattern of people in Japan, Europe, the United States and Canada have a greater adverse impact per capita on the world's environment than that of a subsistence farmer in Bangladesh, for example. Although they represent 20% of the world's population, the 1.2 billion people living in developed countries consume an estimated 67% of all resources and generate 75% of all waste and pollution.
There are many important interactions between population growth, consumption, environmental degradation and health. Human activity has already transformed an estimated 10% of the Earth's surface from forest or rangeland into desert. The productive capacity of 25% of all agricultural lands, an area equal to the size of India and China combined, has already been degraded. Unproductive land and food scarcity currently contribute to malnutrition among 1 billion people, with infants and children suffering the most serious health consequences.
Environmental degradation, declining food security and uncontrolled epidemics of communicable diseases have slowed, and even reversed, the demographic transition to low death rates in some poor countries. In contrast to developed countries, where cardiovascular diseases and cancer are the leading causes of death, in poor countries infectious diseases cause 45% of all deaths.
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.
2. 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.
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. In fact, 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.
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 evolved 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.
It is an established fact that environment has a direct impact on the physical, mental and social well-being of those living in it. The environmental factors range from housing, water supply and sanitation, psychosocial stress and family structure through social and economic support systems, to the organization of health and social welfare services in the community.
In fact the occurrence, prevention and control of disease lies in the environment. If the environment is favourable to the individual, he or she can make full use of his or her physical and mental capabilities. On the contrary, if the environment is polluted it can affect the human health and his susceptibility to illness.
Thus, protection and promotion of ‘environment health’ is one of the major global issues today. It includes the issues of urban environmental health, water quality and health, air quality and health, industry and health, and energy and health.
The term ‘Human Rights’ refers to those basic rights which are essential for the development of human personality such as the right to life, liberty, property and security of an individual. The ‘Universal Declaration of Human Rights’ adopted by the United Nations on December10, 1948, states that-“the inherent dignity of all members of the human family is the foundation of freedom , justice and peace in the world”. This is possible only when each and every human being enjoys fundamental rights, which include:
- The right to life, liberty and security of persons;
- The right to own property;
- The right to freedom of opinion and expression;
- The right to an adequate standard of living;
- The right to seek and to enjoy in other countries asylum from persecution.
- The right to education, freedom of thought, conscience and religion; and
- The right to freedom from torture and degrading treatment,
- The methods and strategies of imparting value education are many and varied. The selection depends much upon the value chosen, sources of development of these values and other limiting factors. The following approaches can be used for teaching values in character building activities:
- Telling: It is a process for developing values to enable a pupil to have a clear picture of a value- laden situation by means of his own narration of the situation.
- Inculcating: It is an approach geared towards instilling and internalizing norms into person’s own value systems.
- Persuading: it is the process of convincing the learner to accept certain values and behave in accordance with what is acceptable.
- Modelling: Modelling is a strategy in which a certain individual perceived as epitomizing desirable/ ideal values is presented to the learners as a model.
- Role playing: acting out the true feelings of the actor/ actors by taking the role of another person but without the risk of reprisals.
- Simulating: It is a strategy in which the learners are asked to pretend to be in a certain situation called for by the lesson and then to portray the events and also by imitating the character’s personality.
- Problem solving: It is an approach wherein a dilemma is presented to the learners asking them what decision they are going to take.
- Discussing situations, stories, pictures, etc: This technique asks the learners to deliberate on and explain the details in the lesson.
- Studying biographies of great men: This is an approach that makes use of the lives of the great men as the subject-matter for trying to elicit their good deeds and thoughts worthy for emulation.
- Moralizing: It is the process of working out a sense of morality through active structuring and restructuring of one’s social experiences (e.g. Moral reasoning and analysis).
- Value clarification: It may be considered as learner-centered. It relies mainly on the pupil’s ability to process his beliefs and behave according to his beliefs, and also, to make a decision whenever confronted with the value dilemma.
AIDS, the Acquired immune-Deficiency Syndrome is a fatal illness caused by a retrovirus known as the Human Immune-Deficiency Virus (HIV) which breaks down the body’s immune system, leaving the victim vulnerable to a host of life-threatening opportunistic infections, neurological disorders or unusual malignancies. Once a person is infected with HIV, it is probable that the person will be infected for life. Strictly speaking, AIDS refers only to the last stage of the HIV infection. There are two types of HIV- the most common HIV 1 and HIV 2 (commonly found in West Africa). The high risk groups include male homosexuals and bisexuals, hetero-sexual partners (including prostitutes), clients of STD, intravenous drug abusers, transfusion recipients of blood and blood products, haemophiliacs, and medical and paramedical staff. Since the first clinical evidence of AIDS in USA in 1981, the disease has become a more devastating disease than any other disease humankind has ever faced. It has acquired epidemic like proportion as more than 60 million people all over the world have been infected with the HIV (Africa-13.2%, Americans-13.6%, Asia-60.7%, Europe-12.0% and Oceania-0.5%).
Estimates of HIV infection cases in India are about 3.5 million. HIV sentinel surveillance data shows Maharashtra as the most affected state followed by Tamil Nadu, Andhra Pradesh, Karnataka and Manipur.
Various Problems Affecting the Women and Welfare
- Malnutrition
Pregnant women, nursing mothers and children are particularly vulnerable to the effects of malnutrition. The adverse effects of malnutrition on women are-maternal depletion, low birth weight, anaemia, toxemias of pregnancy, post-partum haemorrhage, all leading to high mortality and morbidity. Measures to improve the nutritional status of women and children may be broadly divided into two-direct and indirect nutrition interventions. Direct interventions cover a wide range of activities, such as, supplementary feeding programmes, distribution of iron and folic acid tablets, fortification and enrichment of foods, nutrition education, etc. indirect interventions include control of communicable diseases through immunization, improvement of environmental sanitation, provision of clean drinking water, family planning, food hygiene, education and primary health care.
2. Infections
Women or maternal infections can cause a variety of adverse effects such as threatened abortions, foetal growth retardation, low birth weight, embryopathy and puerperal sepsis. Women of under-developed nations are at high risk. Infections in the child may begin with labour and delivery and increase as the child grows older. Children may be ill with debilitating diarrhoeal, respiratory and skin infections, or the situation is further aggravated by the chronic infections, such as, malaria and tuberculosis. The children also suffer from the severe protein-energy malnutrition and anemia. Prevention and treatment of infections in women and children is being done by adopting the WHO Expanded Programme on Immunization. The children in the developing countries are being immunized against tuberculosis, diphtheria, pertusis (whooping cough), tetanus, measles and polio.
3. Uncontrolled reproduction
The severe health hazards for the women and children resulting from the unregulated/uncontrolled reproduction have been well recognized, viz., increased prevalence of low birth weight babies, severe infections and a high maternal and perinatal mortality. Statistics have shown that in most countries, a birth rate is associated with a high infant mortality rate and child death rate.
4. Education and socio-economic status
The dropout rate (from schools) of girls is much higher than the boys. In under-developed nations the educational preference, both at the primary level and at secondary level, is given to the male child as compared to the female child. This also indirectly affects the socio-economic status of the women. This problem is very much under control by making the female education free at the primary level by the several under-developed nations. In India too, the female literacy rate has gone up to 50% from 39.3%.
Role of Information Technology in Human Health
Its various applications include:
- Bioinformatics and osteoporosis
The application of bioinformatics is in the emerging possibility for the cure of osteoporosis-a crippling disease caused by the breakdown of bone, caused by a class of molecules called Cathepsin K. Now the pharmaceutical companies have to find a drug that blocks the Cathepsin K gene only.
- Role in genome sequencing
Bioinformatics played a key role in the final stages of the Human Genome Project. In just four weeks, James kent a Ph.D student of California University produced a computer programmers that helped the public consortium to complete the sequencing in time and to present the draft sequence along with Celera Genomics on June26, 2000.
- DNA databases or data banks having genetic information about populations together with their personal physical characteristics (eye colour, height, weight, etc.), finger prints, dental records, medical records, financial records, etc. are used by the Government Departments to identify missing persons, by the investigating agencies (e.g., FBI, CBI, RAW, etc.) to identify criminals, and also by the insurance companies to prevent insurance fraud.
- Many organizations, such as WHO, maintain their web sites with information about endemic, epidemic and communicable diseases to inform people about dangers involving populations.
- Information about new drug release, their mode of action, indications and risk are also available on web sites.
- Any new development in the field of surgery is also available on net to be referred by the doctors of any country at any time.
- Telemedicine and distance medicine is now far-reaching along with documentation and display of human anatomy with the help of internet.
REFERENCES TEXT BOOKS :
1. Text book of Environmental Studies for Undergraduate Courses by Erach Bharucha for University Grants Commission, Universities Press.
2. Environmental Studies by Palaniswamy – Pearson education
3. Environmental Studies by Dr.S.Azeem Unnisa, Academic Publishing Company
4. Textbook of Environmental Science by Deeksha Dave and E.Sai Baba Reddy, Cengage Publications.
5. Text book of Environmental Sciences and Technology by M.Anji Reddy, BS Publication.
6. Comprehensive Environmental studies by J.P.Sharma, Laxmi publications.
7. Environmental sciences and engineering – J. Glynn Henry and Gary W. Heinke – Prentice hall of India Private limited.
8. A Text Book of Environmental Studies by G.R.Chatwal, Himalaya Publishing House
9. Introduction to Environmental engineering and science by Gilbert M. Masters and Wendell P. Ela - Prentice hall of India Private limited.
