Is TV delaying child development?

By Clare Murphy
BBC News health reporter



Does CBeebies have a lot to answer for?

New research suggests having the TV on may impair young children's development by reducing the amount of conversation between infant and adult. So how bad is the box for young minds?

A US team recorded more than 300 children aged between two months and four years on several days every month over two years.

They found that when the TV was audible - either on in the background or being watched - the number of words spoken and sounds made by either adult or child reduced considerably.

It is the latest study to imply that delays in language development may be the fault of TV, a medium blamed for a host of other modern ills, from bullying to obesity. But while it is not without its problems, experts warn that to expunge it from our children's lives completely may be as undesirable as it is unrealistic.

Mixed picture

Certainly there is a body of research building up that finds a correlation between heavy TV viewing at an early age and linguistic problems.

This study is the first to demonstrate that when the television is on, there is reduced speech in the home

Dimitri Christakis
Lead researcher
The exact nature of the relationship is unclear, and the role that family circumstances and other social influences play has not been established. However lack of interaction at a personal level is thought to be a key culprit.

But there is equally evidence that, for those over two at least, monitored levels of age-appropriate programmes can in fact foster language skills and indeed improve attention.
Watching with an adult and discussing the contents after a shared experienced has been found to be particularly beneficial, but not always necessary providing children are watching high-quality, tailored programmes which contain familiar words and scenarios.

Indeed some psychologists argue that given young children cannot read their own books or surf the internet, watching may be an empowering experience that gives them access to other worlds which present useful information in a way their parents may not be able to.

But there are some serious caveats: what appears to be particularly undesirable is the viewing of general audience or adult programmes both alone or in the company of a carer.


National Literacy Trust's TV tips
Limit TV time to one hour for 3-5 year olds
Where possible, watch together
Switch off when finished
Encourage imaginative play based on what was watched
Videos/dvds may be better due to repetition of words
Avoid TV in the bedroom

In addition while some TV may be beneficial for the over twos, the evidence for those younger is more shaky. First words, it is argued, are learnt far more effectively from real people than voices on the TV.

In the US, the American Academy of Paediatrics recommends no exposure to TV and computer screens for those under two, but lack of evidence for such a measure means there is no such policy in the UK.

Constant hum

This latest study into TV's effect on children comes from the University of Washington's Dimitri Christakis, the researcher who made headlines after reporting that infants who watched the Baby Einstein series - a set of programmes billed as educational - learnt fewer new words than those who did not.

His new study did not differentiate between TV being watched or background TV, nor did it examine the kind of programmes that were on. But it did find that overall, adults barely spoke to children when the TV was audible.

Research published last year also in the US also found problems with background TV, concluding that it affected both the quality and quantity of play in young children.

Liz Attenborough, director of Talk to Your Baby at the UK's National Literacy Trust, agrees that the permanent presence of the TV in the background is something parents should try to reduce.

"Even if you think you're not paying attention to it, you probably are - and this may well interfere with how much you speak to your child. The TV shouldn't be on all the time.
"But we are lucky to have some high-quality children's programmes in the UK. They are usually well thought-out, often featuring a clear, single voice, and incite children to make responses," she said.

"Of course we need to be aware of the problems TV can pose, but equally we don't want to throw the baby out with the bathwater."

Tourism benefits and drawbacks

In general, tourism has several advantages as a sector for pro-poor economic growth (Ashley et al., 2000):

Ø The consumer comes to the destination, thereby providing opportunities for selling additional goods and services.
Ø Tourism is an important opportunity to diversify local economies. It can develop in poor and marginal areas with few other export and diversification options. Remote areas particularly attract tourists because of their high cultural, wildlife and landscape value.
Ø It offers labour-intensive and small-scale opportunities compared with other non-agricultural activities, employs a high proportion of women and values natural resources and culture, which may feature among the few assets belonging to the poor.
In case tourism is being considered as one of several land use options, an assessment should be carried out of the likelihood of all the benefits and drawbacks, or advantages and limitations. At the same time, they represent the key issues to bear in mind in impact assessments and in strategies to maximise tourism's benefits and minimise negative impacts. Note that especially many of the disadvantages are not unique to tourism, but can be attributed to other economic activities in rural areas as well. The table gives a listing of the main points, as they have emerged from numerous analyses of tourism practice (many interesting cases illustrating these issues and ways to address them can be found in Boo, 1990; Lindberg, 1991; Wight, 1991; Whelan, 1992; Wells & Brandon, 1992; Lindberg et al, 1993 and 1998; McIntyre, 1993; Ceballos-Lascurain, 1996; France, 1997; Goodwin et al., 1998; Ashley et al., 2000; Carey et al., 2000).

Table. Advantages and Limitations of Tourism for Development




Advantages
- the positive scenario




Limitations and disadvantages

- the negative scenario



For local development


Ø Jobs (also for labour force with little formal education)

Ø Community income

Ø Enterprise opportunities

Ø Opportunities for training skills and upward mobility

Ø Diversify livelihoods

Ø Improved infrastructure and community facilities in marginal areas

Ø Institutional development

Ø Renewed cultural pride and self-esteem, appreciation of natural and cultural heritage

Ø Recreational and cultural facilities can also be used by residents


Ø Menial jobs only

Ø A ‘bad deal’ for communities

Ø Limited spin-off, high leakage

Ø Limited investment in training

Ø Inequitable distribution of all the above

Ø Conflict with agriculture and livelihood strategies. Risky investment.

Ø Infrastructure only for tourists, not residents, may result in hostility

Ø Local conflicts exacerbated

Ø Control by outsiders

Ø Disempowerment of residents

Ø Cultural disruption

Ø Conflicts over land rights

Ø Conflicts over resources between locals and migrants attracted by tourism success

Ø Possible competition with tourists for basic commodities makes them too scarce or expensive for locals (water, staple foods)





For economic growth


Ø Growing industry

Ø Steady prices (compared to traditional exports)

Ø Job creation, spin-off enterprises, and multiplier effects

Ø Attracts private investment

Ø Economic diversification

Ø Sustainable utilisation of natural assets

Ø Increased markets for local products




Ø Volatile demand

Ø High leakage out of economy; enclave tourism with few spin-offs

Ø Private control not partnership

Ø Over-dependence

Ø Over-use of natural resources

Ø May divert investments from other sectors or regions of higher local importance to tourism infrastructure elsewhere







For conservation


Ø Improved environmental quality

Ø Increased local benefits from wildlife justify its management as a land use option

Ø Enhanced local appreciation of values of nature

Ø Enhanced environmental awareness among tourists; possibly become private donors to conservation projects

Ø Economic justification for establishing PAs or investing in more effective management

Ø Revenues help to cover costs of conservation




Ø Benefits insufficient, narrowly distributed, and not visibly linked to conservation of the resource base.

Ø Capacity and other prerequisites lacking

Ø Conflicts with wildlife protected as tourist attraction (health risks, crop damage)

Ø Deforestation for infrastructure development or to supply fuel wood to tourists

Ø Pollution due to absent waste or sewage treatment at tourism facilities

Ø Disturbance of wildlife, trampling of sensitive vegetation

Ø Immigration as result of tourism success increases pressure on sensitive ecosystems

Tourist attraction, rising oxymoron

Tourism: attraction and drawbacks


New York's Little Italy not so Italian anymore
By Alvin Powell
Harvard News Office

Tourism changes everything it touches, homogenizing and sanitizing even as it brings in bodies and dollars.

This is tourism's "central paradox," according to Susan Fainstein, a Columbia
Columbia's Susan Fainstein explains that exotic locales marketed for their distinct culture and history become a little less exotic when the streets are teeming with tourists instead of local residents. (Staff photo Justin Ide/Harvard News Office)
University professor and author of the book on tourism "The City Builders." It's the task of local officials and regulators, she said, to keep those homogenizing forces in check even as they promote what can be an important contributor to a region's economy.

Fainstein, who spoke at the John F. Kennedy School of Government's Taubman Building on Thursday afternoon (March 4), outlined tourism's benefits and drawbacks in a presentation before about 40 people in the Taubman's Allison Dining Room. The event was sponsored by the Taubman Center for State and Local Government.

The point of tourism is to escape, even briefly, from life's problems, Fainstein said. So tourist destinations are under pressure to make themselves prettier, to add entertainment and insulate tourist areas from crime, and to hide away evidence of manual labor and poverty.

Exotic locales marketed for their distinct culture and history become a little less exotic when the streets are teeming with tourists instead of local residents. Some locations even change their physical look to meet the expectations of tourists, who in this information age can research even the most remote locations and who arrive with bags packed with expectations as well as garments.

"The old places take on new clothes," Fainstein said. "The real places are scurrying to remake themselves to match the expectations of what people think they should be."

Fainstein described different types of tourist destinations, each with their own characteristics. Tourist cities, such as Cancun and Las Vegas, are created with the tourist in mind. Converted cities, such as Detroit and San Antonio, have more uneven development, and attempt to keep tourists segregated from the rest of the city in special districts.

"In an effort to protect visitors from the city, they are separated," Fainstein said.

Her talk dealt mostly with a third category of city, historic and multicultural cities. Tourism in these cities tends to be much more integrated with the fabric of life.

But in integrating, tourism also changes.

Fainstein offered many examples, describing how tourism changes the experience of a place. Touring a historic European church, she said, is a different experience entirely from worshipping there. Touring a castle, she said, is a different experience from visiting there at the bequest of the king.

Given enough time, she said, tourism becomes part of the fabric of a place. In Venice, for example, glassmakers have been making things for tourists for so long that they're part of the background.

"For 200 years, people have been spinning glass to sell to tourists. That's what people in Venice do," Fainstein said. "The meanings of the places have changed."

Tourism promotes what Fainstein termed "fakery" such as the neighborhood Italian restaurants in New York's Little Italy, where the neighborhood these days is mostly made up of ethnic Asians, rather than Italians.

Though tourism has its drawbacks, it's not purely negative. As a form of economic development, it can be more stable than manufacturing, Fainstein said. Manufacturing jobs can be shipped out of state or overseas, but tourists coming to New York City can't go anywhere else but New York.

Jobs in the tourism industry have been criticized as being low-wage, seasonal, and exploitative. But Fainstein said they're also low-skilled, which makes them accessible to entry-level workers or those laid off from manufacturing jobs.

In addition to bringing dollars to a region, tourism can foster positive change.

Sports teams, conventions, and cultural institutions enrich the life for city residents as well as for visitors, she said.

In Harlem, Fainstein said, tourism has helped revive black culture. Streets are better lit, and jazz clubs and restaurants have opened. Still, Fainstein said, there is resentment among some residents.

"People say, I don't want to be in a 'zoo' walking down the street while a bus full of people seeing 'real life' goes by," Fainstein said.

That highlights the tension that tourism has always brought. The tension is familiar in traditional summer resort areas such as Cape Cod, where the local residents dread the annual onslaught of tourists, even as they rely on them for their livelihood.

"Tourism always inspires ambivalence among the people being visited," Fainstein said. "There is a question whether culture can be maintained, because once you sell it and market it, you change it."

Energy of the future

Some countries use fossil fuels such as coal, gas, ... Other countries encourage the use of alternative sourses of energy such as wind and solar power.

What might be positive and negative development of each?
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Current energy sources will not be able to sustain our growing society. We must look to alternate energy sources for the answer.

For further readings on alternative energy (hydro, solar, wind, biomass, nuclear) pls read this (20 pages)
https://www.wellsfargo.com/downloads/pdf/about/csr/alt_energy.pdf
================

Alternate energy sources must replace our traditional energy sources because they are sustainable for our lifestyles. Since the age of industrialization, we have relied heavily upon traditional energy resources (mostly the burning of fossil fuels such as coal, oil, and natural gas). These traditional resources have shaped our culture as well as our development. However, when these resources are used to produce energy, they negatively impact our delicate environment. They are also nonrenewable and will one day run out. However, we may solve the problem of our depleting resources through current technology, which promise new alternative methods to produce energy. Using these alternative resources will greatly increase our sustainability.

Alternative sources must replace traditional sources because they are renewable (the resource will never deplete). One example of an alternate resource is hydroelectricity which generates power via moving water. Due to the hydrologic cycle, the fast-moving water will never deplete. Hydroelectricity is therefore a renewable energy resource. Another example of renewable energy is solar power, which generates energy by collecting heat or light from the sun. Since the sun will not stop emitting heat and light (at least not for the next 4,000,000,000 years) it is considered a renewable resource. Wind can also be used to generate large amounts of electricity. As long as the sun’s heat creates wind currents, we will be able to produce power from the wind. Coal will be gone in 200 years, whereas natural gas will have disappeared in less than 100 years. However, these three resources mentioned above, hydro, solar, and wind power, cannot be depleted.
Another advantage alternative power sources have over traditional sources is that they have little to no impact on the environment. Hydroelectricity relies solely on fast-flowing water to generate power. Once a hydroelectric dam is operating it does not emit any pollutants into the atmosphere. Geothermal energy is considered to be the cleanest energy resource yet explored. A geothermal plant does not burn any fossil fuels and requires minimal land space to operate. Its environmental impact is nearly zero. Hydrogen energy promises to be an excellent substitute to gasoline products currently used in cars and trucks. The element hydrogen is much more powerful per liter than gasoline. Unlike gasoline, the exhaust products of hydrogen do not pollute the atmosphere with CO2 or CO1 (carbon dioxide and carbon monoxide respectively) but release clean H­2O (water). Since alternative energy sources have minimal effects on the environment, the must be used as substitutes for traditional energy sources which are currently trashing our earth.

The only disadvantages of alternative energy are that they are often unreliable and have high start-up costs. For example, solar energy requires a great number of solar cells to produce any significant amount of electricity. The cells are expensive and may not be affordable for family households or small companies. They also only produce electricity on sunny days. Because the sun is not always shining, the source is not reliable. Another example of an energy resource that is expensive to start up is hydroelectric dams. Though running costs are cheap the building of a hydroelectric dam far exceeds that of a fossil-fuel-burning plant. Many governments and companies may stay away from alternative energy sources such as these because the resource is unreliable or they cannot afford the initial start-up costs.
Alternative energy has more benefits than drawbacks. Unlike traditional resources, it is renewable and has little to no impact on the environment. The only drawbacks to these sources are that they are often unreliable and command high startup costs. Our current technologies employed to produce energy are not sustainable. The resources will not last for future generations. We therefore need to move to alternate energy resources to ensure that our lifestyles are sustainable, both for us and for future generations.

Nuclear Technology: benefits and risks

The benefits of nuclear technology in agriculture


by Monish Gunawardana*

Nuclear power can be used to wipe out our civilization within a few minutes. In 1945, two atom bombs wiped out millions of civilians in two Japanese cities, Hiroshima and Nagasaki. Today, our planet houses nearly 22,000 nuclear weapons. But let us discuss how to employ nuclear technology to bring food to all people.

Radioisotopes are are used in agriculture to control pests, study fertilizer or prevent waste of grain in stores. At the beginning, isotopes were mainly used for medical diagnosis, with the patient being given the radioisotopes in a chemical form to concentrate in the organ to be studied. The radiation can then be easily detected outside the patient's body by a scanner.

Improving agricultural productivity by utilizing advanced technology is crucial to guarantee food security for all. The Food and Agriculture Organization (FAO) has recognized that nuclear energy can improve development, including agriculture, horticulture, forestry and improved levels of nutrition. The FAO and International Atomic Energy Agency (IAEA) work hand in hand in promoting nuclear-related technologies to achieve these goals.

The IAEA promotes radioisotopes to study the growth and nutrient needs of agricultural crops in dry areas. These studies help agricultural scientists to introduce efficient water management systems and crop varieties to water-deficient lands. The FAO has introduced some fertilizers labeled with nitrogen-isotopes (15N), to use and identify the best growing conditions for crops in dry lands in Burkina Faso, Mali, Niger and Senegal.

Inadequate preventive maintenance generates leakages in the irrigation schemes, while poor irrigation management makes soil saline (saltiness of the soil). Around 40 percent of the world's food is grown utilizing irrigation schemes and 10 percent of agricultural lands in the world have become unproductive by salinity. However, the above-mentioned nuclear-scientific interventions help drought-ridden nations to grow food successfully.

IAEA encourages radioisotope techniques to improve fertilizer applications. It could estimate the exact amount of water and nutrients needed for a certain crop. The optimal use of fertilizers and water helps farmers to grow food with good quality at lower production costs. The application of fertilizers via major irrigation schemes and minor waterways within the farmland can bring many benefits to the farmer. Some of those benefits are saving water, nitrogen fertilizers,labour and farm implements' costs.

Radiation techniques can control pests and insects that destroy food crops. It is used to rear insects en masse and sterilise them with gamma radiation. Then, these unproductive insects are released to compete with wild males for mating. Over time, this nuclear-based technique begins to eradicate insects that are harmful to agricultural crops.

Using Sterile Insects Techniques (SIT), Guam and Marian's islands have eradicated fruit flies. In 2001, the FAO, IAEA and World Health Organization extended SIT programmes to 37 Sub-Saharan African countries to control the Tsetse Fly that causes sleeping sickness and cattle diseases like Magana, which cause US$4 billion economic losses per year.

With the help of nuclear radiation, IAEA/FAO agricultural scientists have introduced nearly 400 varieties of high-yield and disease-resistant rice to Vietnam and other rice -producing countries. This is done by changing the inherited characteristics of plants exposed to radiation.

Protein-rich wheat in India and high-yield rice and early maturing soya beans in Japan are some examples of the new generation of plants bred by radiation technology. These new breeds of plants consume less water, fertilizer and time to produce grains, fruits or vegetables. In addition, they are more resistant to pests and diseases than traditional crops. Therefore, the new strain of plants produced by nuclear applications would trim down the production costs of agriculture and improve the food security of many nations, predominantly in the developing countries.

The Indira Gandhi Center for Atomic Research at Kalppakkam in India, using nuclear tools, introduced advanced varieties of green grams, black grams and red grams. Moreover, it introduced tissue culture in sugarcane in Maharastra region.

Around two billion of people around the world do not have easy access to safe drinking water. They use contaminated water sources. Because of that, water-borne diseases could increase the poverty of developing nations. Under the guidance of the IAEA and FAO, hydrologists using nuclear means try to locate and protect springs and other water sources. Their tool is the isotope. For instance, in an area in Uganda, a community spring began to generate contaminated water. Isotope hydrologists found the source for the spring as a swamp in the mountain. After that they took steps to protect the swamp. Now that spring water is safe and clean.

In Abidjan, Ivory Coast, a few years ago people began to complain about the contaminated ground water. Hydrologists using nitrogen-isotopes identified the reason as the worn-out underground sewage network of the area.

Industrialized nations and emerging economic powers in Asia have recognized the great significance of nuclear applications in agriculture, industries, medicine, water and power supply. The nuclear-scientific approach is a viable solution for global socio-economic advancement.

*Professor, International University of Management, Namibia
Atoms for peace: Extending the Benefits of Nuclear Technologies
http://www-tc.iaea.org/tcweb/archives/articles/atomsforpeace.asp
Through IAEA-supported projects, beneficial nuclear technologies are contributing to national development goals.
by Jihui Qian and Alexander Rogov
________________________________________
Over the past 40 years, a disease known as rinderpest, or "cattle plague", has been devastating for farmers in Africa, claiming the lives of millions of cattle and severely hurting farm production and income. Especially in the 1980s, serious outbreaks of rinderpest in livestock were reported throughout Africa.

Today, that picture has changed. Out of 18 African countries where cattle once were infested with rinderpest, only two show signs of the disease today. Instrumental to this remarkable turnabout has been a Pan-African campaign that incorporated the application of a new nuclear-based testing technique developed jointly by the IAEA, Food and Agriculture Organization (FAO) of the United Nations, and a laboratory in the United Kingdom in 1987. The application has radically increased the effectiveness of vaccination campaigns against cattle plague, enabling African countries to declare themselves free of the disease. Veterinarians in these countries received support from the IAEA's technical co-operation programme and an FAO/IAEA coordinated research programme. They were supplied with necessary testing kits, equipment, training, and technical support to ensure the correct use of the technique in national veterinary laboratories. Participating laboratories throughout Africa now have acquired the expertise and skills they need to carry out effective testing.

The project's success is leading to similar work in other regions of the world. A global rinderpest campaign has been launched with the aim of eradicating the disease over the next 20 years. Under a 4-year IAEA technical co-operation project, the techniques developed through the FAO/IAEA's work in Africa will be part of efforts for rinderpest surveillance and control in West Asia. Countries there currently are suffering millions of dollars in losses from animal deaths. The IAEA regional project aims to help these countries eradicate rinderpest by the turn of the century.
The case of rinderpest is just one example of how international and national scientists are working together to bring practical benefits to people through technology-transfer projects supported by the IAEA. In other fields as well including medicine, environmental protection, and food preservation, for example - nearly, 1300 IAEA-supported projects are making key contributions around the world. This article looks at the kinds of projects cooperatively undertaken through IAEA mechanisms to extend the reach of beneficial nuclear technologies in response in increasing demands for technical support and assistance from its Member States.
Evolution of international nuclear co-operation

In the early 1950s, the international community was first becoming aware of the great opportunities that peaceful applications of atomic energy could offer for economic and social development. It was also becoming apparent that, for most countries, these opportunities could be materialized in a most effective manner through extensive and concerted international efforts.

In this environment, on 4 December 1954, the United Nations General Assembly unanimously passed an "Atoms for Peace" resolution expressing the hope that an international atomic energy agency would be established without delay to facilitate the use by the entire world of atomic energy for peaceful purposes, and to encourage international co-operation in the further development and practical use of atomic energy for the benefit of humanity.

At the time when the IAEA was established in 1957, only a limited number of countries had knowledge and experience in nuclear research, and especially its practical application. At the first International Conference on the Peaceful Uses of Atomic Energy, held in Geneva in August 1955 and attended by scientists and engineers from 73 countries, less than half of participating States were able to present reports on nuclear science or technology and only 12 of these States were from developing areas of the world.

In framing the IAEA's Statute, governments sought to create an international institution through which countries could receive multilateral technical assistance on peaceful nuclear research and applications. The Statute stipulates a range of conditions for countries to receive such assistance. These include, inter alia, the usefulness of the project, including its scientific and technical feasibility; the adequacy of plans, funds, and technical personnel to assure the effective execution of the project; and the adequacy of proposed health and safety standards for handling and storing materials and for operating facilities.

Back in 1957, however, the basis for technical assistance activities was fairly weak. The sphere of co-operation was relatively limited covering mainly nuclear power and aspects of its fuel cycle, and to a certain extent some aspects of radiation applications. Very few peaceful nuclear technologies had reached the level of maturity which enabled them to be effectively used for practical applications. At that time as well, most developing countries were not yet at the stage where they could effectively apply nuclear science and technology. It should also be noted that, in the early years, none of the three partners involved in the technical assistance process i.e. donor countries, recipient countries, and the IAEA - had neither the required experience nor administrative arrangements for multilateral intergovernmental co-operation.

Today, the situation is different. Most IAEA Member States from the developing world have gained knowledge and experience in many fields of nuclear research and applications, mainly those related to basic human needs. Mechanisms for technology transfer have been put into place, and their effectiveness is continually reviewed. IAEA activities cover practically all areas of peaceful applications of nuclear energy, and interest in receiving technical assistance is growing.

People in many countries around the world are seeing benefits of nuclear technologies in their lives, through IAEA-supported projects in fields of health care, water management, agriculture, and industry, for example. (Credits: J: Aranyossy and V. Mouchkin, IAEA)
Priorities and needs

What kinds of technical assistance are countries receiving? In terms of total annual disbursements through the IAEA's technical co-operation programme, the largest share is for projects related to nuclear applications in food and agriculture, which accounted for about 22% of disbursements in 1994. Nuclear-related methods are widely used in developing countries in such areas as plant breeding, soil fertility studies, insect and pest control, animal production and health, and studies of the fertilizer efficiency and the fate of agrochemicals and residues. The technology of food irradiation additionally is finding increasing acceptance as an effective means of protecting agriculture products from spoilage, and as a method for controlling pathogens associated with serious food-borne diseases and for meeting the strict quarantine requirements of international food trade.

Another major area of interest is the use of nuclear technologies in physical and chemical sciences, and in fields of industry and earth science. This includes the utilization of research reactors and particle accelerators for scientific studies, production of isotopes; the application, maintenance and repair of nuclear instrumentation; and the preparation and utilization of radiopharmaceuticals. Over the 1990-94 period, the share of total disbursements in this area have ranged between 18% and 25%. Other areas showing high levels of interest are nuclear applications in industry and earth sciences - including non-destructive testing of materials and products, radiation processing, and development of water resources, for example and nuclear-related health care and treatment. Greater support, for instance, is being requested in the use of nuclear techniques for the diagnosis of many diseases, such as leishmaniasis, Chagas disease, iodine deficiencies, and sickle cell diseases. At the same time, the use of ionizing radiation to treat cancer is drawing more and more interest. Currently the IAEA has 40 technical co-operation projects associated with radiotherapy in 29 countries. Additionally, nuclear methods and technologies are used for sterilization of biological tissues and medical supplies, and for nutritional and health-related environmental studies.
An area of shifting demand is nuclear power and safety. While nuclear power programmes in many countries have been cut back or halted, there is increasing awareness of the needs for nuclear safety and radiation protection. The share of disbursements on nuclear power has dropped from about 12% in the late 1980s to 6% in the 1990s, whereas the share for safety and radiation protection has grown. Projects being supported include those related to strengthening national infrastructures for radiation protection; occupational safety of radiation workers; safety of nuclear installations; the safe management, storage, and disposal of radioactive wastes; and nuclear emergency planning and preparedness.

On average over the past 5 years, countries have received technical assistance from the IAEA valued at about US $40 million per year through expert services, provision of equipment, and training activities. All told over the past 25 years, the cumulative resources available to the IAEA's technical co-operation programme amount to nearly US $690 million.
Realizing the benefits

As the rinderpest example illustrates, a number of techniques developed and applied with the IAEA's assistance are significantly contributing to the solution of serious problems hampering social and economic development. Some selected other cases may help to indicate the number of different ways in which the IAEA's assistance can be applied.

Water resources. The assessment and development of water resources has been a major area of IAEA activity for more than 30 years. Nuclear and isotope techniques play a valuable role in hydrological investigations. Under one current project, in Venezuela, IAEA scientists are helping local water authorities in Caracas study the potential of an aquifer to provide additional water for residential, agricultural, and industrial needs. A rapid increase in the population of Caracas has led to a deficit of nearly 20% in the water supply, and more water resources must be found. Studies will help Venezuelan authorities make decisions concerning the best use of the aquifer, and how to protect its water from pollution.

Animal health and productivity. Buffaloes and cattle in Asia are fed mainly with rice straw and native grasses. However, these materials are very indigestible and have only limited amounts of the protein, energy, and minerals needed to provide a balanced diet. Poor nutrition seriously compromises the ability of the animals to produce meat and milk and to provide draught power. Through projects jointly supported by the IAEA and United Nations Development Programme (UNDP), assistance was provided to India and Indonesia in using isotopes for investigating the efficiency of the processes involved in feed digestion. As a result, the best combination of local materials for supplementing grass or straw was determined.
In both countries the effect of the introduction of this feed supplementation method has been very high. For example, in India the amount of milk collected by the largest milk co-operative in 1989 increased by 30%, and the price was 25% less than the price of producing milk by the other methods of feed supplementation.
Quality control in industry. Non-destructive testing (NDT) techniques are widely applied in industry and manufacturing for quality control purposes. In Latin America and the Caribbean, an IAEA-supported NDT regional project involving 18 countries was conducted from 1983-94. The overall objective was to assist them in developing an autonomous capability for applying NDT, largely by providing support in areas of training.

The evaluation review carried out by independent experts in 1994 showed that the project had been instrumental in providing the region with a significant technological tool for the advancement of the region's industrialization. This enabled the development of local industries and the displacement of NDT services previously provided from outside the region. The project marked a significant change for the region's own technological development. In previous years, the input from experts from outside of the region was the dominant mode of dissemination of NDT technology. This was often in the context of regional courses, with typically one participant from each project country. Gradually, the dominant mode changed from using external experts to using regional experts and further evolved to the use of national experts teaching courses solely in their respective countries.

Health care. Nuclear and related techniques play an especially vital role in health care and treatment. Among important diagnostic tools is a technique known as radioimmunoassay. With the IAEA's support, more than 250 radioinimunoassay laboratories have been established or upgraded in Africa, Asia, and Latin America, and supplied with reagents in bulk form. has allowed recipient countries to provide reasonable clinical diagnostic services covering important substances such as hormones, vitamins, enzymes and even some tumor markers. The cost of each test is less than US 50 cents per patient sample, which on average is ten times less than the application of complete commercial kits. In some countries, where some of the primary reagents needed are being produced locally, the cost per test is significantly lower. More important than the lower cost is the fact that many people now have access to reliable diagnostic tests that play a key role in the improvement of their health care and treatment.
Future directions

In its current and planned programmes, the IAEA is placing increasingly more emphasis on cost-effective projects that promise significant social and economic benefits, that have a lasting and environmentally sound impact on a country's development, and that clearly demonstrate the value of nuclear applications for end users. The IAEA's Member States have strongly supported this move towards impact-oriented technical co-operation. At an IAEA Technical Cooperation Policy Review Seminar in September 1994, for example, governmental representatives provided the Agency with valuable recommendations regarding the practical implementation of projects important to them.

Undoubtedly the major challenge facing the IAEA's technical co-operation programme in years ahead is the availability of sufficient financial resources to effectively carry out approved projects. In terms of its funding base, the IAEA occupies a place far behind large bilateral and multilateral agencies. Even so, the trend in contributions to the IAEA's technical co-operation programme over the past 5 years has been negative, and many sound projects have had to go unfunded. In response to the situation, the IAEA has taken a number of administrative and programmatic measures intended to stretch its limited resources so as to obtain the best possible results.

These efforts are part of steps to improve programme efficiency, and to attract greater resources enabling the IAEA to enhance its support for technology-transfer activities that are not only operationally sound but visibly effective. As the main channel for global nuclear co-operation, the IAEA possesses an exceptionally high level of technical expertise and experience to identify and carry out a multitude of projects that can make a lasting difference to a country's sustainable development.

RISKS OF NUCLEAR POWER
http://www.physics.isu.edu/radinf/np-risk.htm
Bernard L. Cohen, Sc.D.
Professor at the University of Pittsburgh
________________________________________
Radiation

The principal risks associated with nuclear power arise from health effects of radiation. This radiation consists of subatomic particles traveling at or near the velocity of light---186,000 miles per second. They can penetrate deep inside the human body where they can damage biological cells and thereby initiate a cancer. If they strike sex cells, they can cause genetic diseases in progeny.

Radiation occurs naturally in our environment; a typical person is, and always has been struck by 15,000 particles of radiation every second from natural sources, and an average medical X-ray involves being struck by 100 billion. While this may seem to be very dangerous, it is not, because the probability for a particle of radiation entering a human body to cause a cancer or a genetic disease is only one chance in 30 million billion (30 quintillion).

Nuclear power technology produces materials that are active in emitting radiation and are therefore called "radioactive". These materials can come into contact with people principally through small releases during routine plant operation, accidents in nuclear power plants, accidents in transporting radioactive materials, and escape of radioactive wastes from confinement systems. We will discuss these separately, but all of them taken together, with accidents treated probabilistically, will eventually expose the average American to about 0.2% of his exposure from natural radiation. Since natural radiation is estimated to cause about 1% of all cancers, radiation due to nuclear technology should eventually increase our cancer risk by 0.002% (one part in 50,000), reducing our life expectancy by less than one hour. By comparison, our loss of life expectancy from competitive electricity generation technologies, burning coal, oil, or gas, is estimated to range from 3 to 40 days.
There has been much misunderstanding on genetic diseases due to radiation. The risks are somewhat less than the cancer risks; for example, among the Japanese A-bomb survivors from Hiroshima and Nagasaki, there have been about 400 extra cancer deaths among the 100,000 people in the follow-up group, but there have been no extra genetic diseases among their progeny. Since there is no possible way for the cells in our bodies to distinguish between natural radiation and radiation from the nuclear industry, the latter cannot cause new types of genetic diseases or deformities (e.g., bionic man), or threaten the "human race". Other causes of genetic disease include delayed parenthood (children of older parents have higher incidence) and men wearing pants (this warms the gonads, increasing the frequency of spontaneous mutations). The genetic risks of nuclear power are equivalent to delaying parenthood by 2.5 days, or of men wearing pants an extra 8 hours per year. Much can be done to avert genetic diseases utilizing currently available technology; if 1% of the taxes paid by the nuclear industry were used to further implement this technology, 80 cases of genetic disease would be averted for each case caused by the nuclear industry.
________________________________________
Reactor accidents
The nuclear power plant design strategy for preventing accidents and mitigating their potential effects is "defense in depth"--- if something fails, there is a back-up system to limit the harm done, if that system should also fail there is another back-up system for it, etc., etc. Of course it is possible that each system in this series of back-ups might fail one after the other, but the probability for that is exceedingly small. The Media often publicize a failure of some particular system in some plant, implying that it was a close call" on disaster; they completely miss the point of defense in depth which easily takes care of such failures. Even in the Three Mile Island accident where at least two equipment failures were severely compounded by human errors, two lines of defense were still not breached--- essentially all of the radioactivity remained sealed in the thick steel reactor vessel, and that vessel was sealed inside the heavily reinforced concrete and steel lined "containment" building which was never even challenged. It was clearly not a close call on disaster to the surrounding population. The Soviet Chernobyl reactor, built on a much less safe design concept, did not have such a containment structure; if it did, that disaster would have been averted.

Risks from reactor accidents are estimated by the rapidly developing science of "probabilistic risk analysis" (PRA). A PRA must be done separately for each power plant (at a cost of $5 million) but we give typical results here: A fuel melt-down might be expected once in 20,000 years of reactor operation. In 2 out of 3 melt-downs there would be no deaths, in 1 out of 5 there would be over 1000 deaths, and in 1 out of 100,000 there would be 50,000 deaths. The average for all meltdowns would be 400 deaths. Since air pollution from coal burning is estimated to be causing 10,000 deaths per year, there would have to be 25 melt-downs each year for nuclear power to be as dangerous as coal burning.

Of course deaths from coal burning air pollution are not noticeable, but the same is true for the cancer deaths from reactor accidents. In the worst accident considered, expected once in 100,000 melt-downs (once in 2 billion years of reactor operation), the cancer deaths would be among 10 million people, increasing their cancer risk typically from 20% (the current U.S. average) to 20.5%. This is much less than the geographical variation--- 22% in New England to 17% in the Rocky Mountain states.
Very high radiation doses can destroy body functions and lead to death within 60 days, but such "noticeable" deaths would be expected in only 2% of reactor melt-down accidents; there would be over 100 in 0.2% of meltdowns, and 3500 in 1 out of 100,000 melt-downs. To date, the largest number of noticeable deaths from coal burning was in an air pollution incident (London, 1952) where there were 3500 extra deaths in one week. Of course the nuclear accidents are hypothetical and there are many much worse hypothetical accidents in other electricity generation technologies; e.g., there are hydroelectric dams in California whose sudden failure could cause 200,000 deaths.
________________________________________
Radioactive Waste
The radioactive waste products from the nuclear industry must be isolated from contact with people for very long time periods. The bulk of the radioactivity is contained in the spent fuel, which is quite small in volume and therefore easily handled with great care. This "high level waste" will be converted to a rock-like form and emplaced in the natural habitat of rocks, deep underground. The average lifetime of a rock in that environment is one billion years. If the waste behaves like other rock, it is easily shown that the waste generated by one nuclear power plant will eventually, over millions of years (if there is no cure found for cancer), cause one death from 50 years of operation. By comparison, the wastes from coal burning plants that end up in the ground will eventually cause several thousand deaths from generating the same amount of electricity.

The much larger volume of much less radioactive (low level) waste from nuclear plants will be buried at shallow depths (typically 20 feet) in soil. If we assume that this material immediately becomes dispersed through the soil between the surface and ground water depth (despite elaborate measures to maintain waste package integrity) and behaves like the same materials that are present naturally in soil (there is extensive evidence confirming such behavior), the death toll from this low level waste would be 5% of that from the high level waste discussed in the previous paragraph.
________________________________________
Other Radiation Problems
The effects of routine releases of radioactivity from nuclear plants depend somewhat on how the spent fuel is handled. A typical estimate is that they may reduce our life expectancy by 15 minutes.

Potential problems from accidents in transport of radioactive materials are largely neutralized by elaborate packaging. A great deal of such transport has taken place over the past 50 years and there have been numerous accidents, including fatal ones. However, from all of these accidents combined, there is less than a 1% chance that even a single death will ever result from radiation exposure. Probabilistic risk analyses indicate that we can expect less than one death per century in U.S. from this source.

Mining uranium to fuel nuclear power plants leaves "mill tailings", the residues from chemical processing of the ore, which lead to radon exposures to the public. However, these effects are grossly over-compensated by the fact that mining uranium out of the ground reduces future radon exposures. By comparison, coal burning leaves ashes that increase future radon exposures. The all-inclusive estimates of radon effects are that one nuclear power plant operating for one year will eventually avert a few hundred deaths, while an equivalent coal burning plant will eventually cause 30 deaths.

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Contributed by NguyenDucNam as part of his homework. Thanks Nam

Overpopulation: causes, effects and solutions

Causes of Overpopulation

NB: (This is taken from some sources on the internet. Too long ago I can't remember the link). In fact, this is collected by some students as mentioned at the end of the reading. Thank you.
Pls read this and write an essay on population
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Overpopulation is one of the most serious threats to mankind. It's high time we identify and understand the causes of overpopulation and take steps to avoid it. To know more about the causes of overpopulation, read on…

By definition, overpopulation is the condition where the number of organisms exceeds the carrying capacity of their habitat. We are facing the effects of overpopulation in our daily lives. Overpopulation has impacted the life of common man and has proved to be one of the gravest difficulties that have to be fought. Overpopulation implies scarcity of resources and economic inflation; these are the monsters which can make life miserable. Living through the negative effects of overpopulation have made us realize serious problems associated with it. It is high time we wake up and find the causes of overpopulation and work on them.

Causes of Overpopulation

Decline in the Death Rate: The fall in death rates that is decline in mortality rate is one fundamental causes of overpopulation. Owing to the advancements in medicine, man has found cures to the previously fatal diseases. The new inventions in medicine have brought in treatments for most of the dreadful diseases. This has resulted in an increase in the life expectancy of individuals. Mortality rate has declined leading to an increase in population. Owing to modern medications and improved treatments to various illnesses, the overall death rate has gone down. The brighter side of it is that we have been able to fight many diseases and prevent deaths. On the other hand, the medical boon has brought with it, the curse of overpopulation.

Rise in the Birth Rate: Thanks to the new discoveries in nutritional science, we have been able to bring in increase in the fertility rates of human beings. Medicines of today can boost the reproductive rate in human beings. There are medicines and treatments, which can help in conception. Thus, science has led to an increase in birth rate. This is certainly a reason to be proud and happy but advances in medicine have also become a cause of overpopulation.

Migration: Immigration is a problem in some parts of the world. If the inhabitants of various countries migrate to a particular part of the world and settle over there, the area is bound to suffer from the ill effects of overpopulation. If the rates of emigration from a certain nation do not match the rates of immigration to that country, overpopulation makes its way. The country becomes overly populated. Crowding of immigrants in certain parts of the world, results in an imbalance in the density of population.

Lack of Education: Illiteracy is another important cause of overpopulation. Those lacking education fail to understand the need to prevent excessive growth of population. They are unable to understand the harmful effects that overpopulation has. They are unaware of the ways to control population. Lack of family planning is commonly seen in the illiterate lot of the world. This is one of the major factors leading to overpopulation. Due to ignorance, they do not take to family planning measures, thus contributing to a rise in population.

Viewing the issue of increasing population optimistically, one may say that overpopulation means the increase in human resources. The increase in the number of people is the increase in the number of productive hands and creative minds. But we cannot ignore the fact that the increase in the number producers implies an increase in the number of consumers. Greater number of people requires a greater number of resources.

Not every nation is capable of providing its people with the adequate amount of resources. The ever-increasing population will eventually leave no nation capable of providing its people with the resources they need to thrive. When the environment fails to accommodate the living beings that inhabit it, overpopulation becomes a disaster.

By Manali Oak
Published: 7/29/2008


http://en.wikipedia.org/wiki/Overpopulation

Overpopulation is a condition where an organism's numbers exceed the carrying capacity of its habitat. In common parlance, the term usually refers to the relationship between the human population and its environment, the Earth.[1]
Overpopulation does not depend only on the size or density of the population, but on the ratio of population to available sustainable resources, and on the means of resource use and distribution used by that population. If a given environment has a population of 10 individuals, but there is food or drinking water enough for only 9, then in a closed system where no trade is possible, that environment is overpopulated; if the population is 100 but there is enough food, shelter, and water for 200 for the indefinite future, then it is not overpopulated. Overpopulation can result from an increase in births, a decline in mortality rates due to medical advances, from an increase in immigration, or from an unsustainable biome and depletion of resources. It is possible for very sparsely-populated areas to be overpopulated, as the area in question may have a meager or non-existent capability to sustain human life (e.g. the middle of the Sahara Desert or Antarctica).
The resources to be considered when evaluating whether an ecological niche is overpopulated include clean water, clean air, food, shelter, warmth, and other resources necessary to sustain life. If the quality of human life is addressed, there may be additional resources considered, such as medical care, education, proper sewage treatment and waste disposal. Overpopulation places competitive stress on the basic life sustaining resources, leading to a diminished quality of life.[2]
Some countries have managed to increase their carrying capacity by using technologies such as modern agriculture, desalination, and nuclear power. Not everyone agrees that overpopulation is a bad thing. In his book The Ultimate Resource, economist Julian Simon argued that higher population density leads to more specialization and technological innovation, and that this leads to a higher standard of living.[3] But most sociologists see overpopulation as a serious problem.[2][4]
•
[edit] Population growth
[edit] History


In order to better present the subject of overpopulation, it may be useful to first review the current population of the world in the context of human population from the dawn of civilization to date. Civilization began roughly 10,000 years ago, coinciding with:
• the final receding of ice following the end of the most recent glacial period and
• the start of the "Neolithic Revolution" when there was a shift in human activity away from “hunter-gathering” and towards very primitive farming.
• At the dawn of agriculture, about 8,000BC, the population of the world was approximately 5 million[5].
• Minimal change in population for many thousands of years ending around 1,000BC.
• Steady growth began around 1,000BC which then plateaued (or alternatively peaked) around the year 0.
• The trend for next 800 - 900 years from around 800AD onwards was slow but steady growth, though with major disruption from frequent plagues (most notably the Black Death during the 14th century).
• Yet faster growth from the start of the Industrial Revolution around 1700AD.
• At over 6.7 billion[6] World Population is approximately 3 times higher in 2009 than it was at approximately 2.3 billion or less[7] in 1939, despite loss of life during World War II (an upper estimate of which is some 72 million).
• Dramatic growth since the start of the Green Revolution around 1950 and continuing to the present day. Forecast to carry on growing to 8.9 billion, 9.2 billion, 9.5 billion or perhaps even 11 billion by 2050.

Clearly, an inspection of the graphs above reveals the unusual and very pronounced negative skewing. In this case that means after many thousands of years of minimal population there has, for the first time in human history, been a period of consistently rapid population increase followed more recently by a spectacular and unprecedented increase.

[edit] Projections to 2050
United Nations reports, such as World Population Prospects state:
• World population is currently growing by approximately 74 million people per year. If current fertility rates continued, in 2050 the total world population would be 11 billion, with 169 million people added each year. However, global fertility rates have been falling for decades, and the updated United Nations figures project that the world population will reach 9.2 billion around 2050.[8][9] This is the medium variant figure which assumes a decrease in average fertility from the present level of 2.5 down to 2.
• Almost all growth will take place in the less developed regions, where today’s 5.3 billion population of underdeveloped countries is expected to increase to 7.8 billion in 2050. By contrast, the population of the more developed regions will remain mostly unchanged, at 1.2 billion. The world's population is expected to rise by 40% to 9.1 billion. An exception is the United States population, which is expected to increase 44% from 305 million in 2008 to 439 million in 2050.[10]
• In 2000-2005, the average world fertility was 2.65 children per woman, about half the level in 1950-1955 (5 children per woman). In the medium variant, global fertility is projected to decline further to 2.05 children per woman.
• During 2005-2050, nine countries are expected to account for half of the world’s projected population increase: India, Pakistan, Nigeria, Democratic Republic of the Congo, Bangladesh, Uganda, United States of America, Ethiopia, and China, listed according to the size of their contribution to population growth.
• Global life expectancy at birth, which is estimated to have risen from 46 years in 1950-1955 to 65 years in 2000-2005, is expected to keep rising to reach 75 years in 2045-2050. In the more developed regions, the projected increase is from 75 years today to 82 years by mid-century. Among the least developed countries, where life expectancy today is just under 50 years, it is expected to be 66 years in 2045-2050.
• The population of 51 countries or areas, including Germany, Italy, Japan and most of the successor States of the former Soviet Union, is expected to be lower in 2050 than in 2005.
• During 2005-2050, the net number of international migrants to more developed regions is projected to be 98 million. Because deaths are projected to exceed births in the more developed regions by 73 million during 2005-2050, population growth in those regions will largely be due to international migration.
• In 2000-2005, net migration in 28 countries either prevented population decline or doubled at least the contribution of natural increase (births minus deaths) to population growth. These countries include Austria, Canada, Croatia, Denmark, Germany, Italy, Portugal, Qatar, Singapore, Spain, Sweden, United Arab Emirates and United Kingdom.[11]
• Birth rates are now falling in a small percentage of developing countries, while the actual populations in many developed countries would fall without immigration.[12]
• By 2050 (Medium variant), India will have almost 1.7 billion people, China 1.4 billion, United States 400 million, Indonesia 297 million, Pakistan 292 million, Nigeria 289 million, Bangladesh 254 million, Brazil 254 million, Democratic Republic of the Congo 187 million, Ethiopia 183 million, Philippines 141 million, Mexico 132 million, Egypt 121 million, Vietnam 120 million, Russia 108 million, Japan 103 million, Iran 100 million, Turkey 99 million, Uganda 93 million, Tanzania 85 million, and Kenya 85 million.
1900
• Africa - 133 million
• Asia - 946 million
• Europe - 408 million
• Latin America & Caribbean - 74 million
• Northern America - 82 million
2050
• Africa - 1.9 billion
• Asia - 5.2 billion
• Europe - 664 million
• Latin America & Caribbean - 769 million
• Northern America - 445 million[13]
[edit] Demographic transition


United Nation's population projections by location.
Main article: Demographic transition

The theory of demographic transition, while unproven to apply to all world regions, holds that, after the standard of living and life expectancy increase, family sizes and birth rates decline. Factors cited include such social factors as later ages of marriage, the growing desire of many women in such settings to seek careers outside child rearing and domestic work, and the decreased need of children in industrialized settings. The latter factor stems from the fact that children perform a great deal of work in small-scale agricultural societies, and work less in industrial ones; it has been cited to explain the decline in birth rates in industrializing regions.

Another version of demographic transition is that of Virginia Abernethy in Population Politics, where she claims that the demographic transition occurs primarily in nations where women enjoy a special status (see Fertility-opportunity theory). In strongly patriarchal nations, where she claims women enjoy few special rights, a high standard of living tends to result in population growth.
Many countries have high population growth rates but lower total fertility rates because high population growth in the past skewed the age demographic toward a young age, so the population still rises as the more numerous younger generation approaches maturity.[original research?]

"Demographic entrapment" is a concept developed by Maurice King, who posits that this phenomenon occurs when a country has a population larger than its carrying capacity, no possibility of migration, and exports too little to be able to import food. This will cause starvation. He claims that for example many sub-Saharan nations are or will become stuck in demographic entrapment, instead of having a demographic transition.[14]

For the world as a whole, the number of children born per woman decreased from 5.02 to 2.65 between 1950 and 2005. A breakdown by continent is as follows:
• Europe 2.66 to 1.41
• North America 3.47 to 1.99
• Oceania 3.87 to 2.30
• Central America 6.38 to 2.66
• South America 5.75 to 2.51
• Asia (excluding Middle East) 5.85 to 2.43
• Middle East & North Africa 6.99 to 3.37
• Sub-Saharan Africa 6.7 to 5.53
In 2050, the projected world number of children born per woman is 2.05. Only the Middle East & North Africa (2.09) and Sub-Saharan Africa (2.61) will then have numbers greater than 2.05.[15]

[edit] Carrying capacity
Main article: Carrying capacity
Estimates of the carrying capacity of Earth range between 1 billion and 1 trillion people, depending on the values used in calculations. The variability of estimates has grown larger since 1950, compared to earlier estimates.[16]
In a study titled Food, Land, Population and the U.S. Economy, David Pimentel, professor of ecology and agriculture at Cornell University, and Mario Giampietro, senior researcher at the US National Research Institute on Food and Nutrition (INRAN), estimate the maximum U.S. population for a sustainable economy at 200 million. To achieve a sustainable economy and avert disaster, the United States must reduce its population by at least one-third, and world population will have to be reduced by two-thirds, says the study.[17]

Steve Jones, head of the biology department at University College London, has said, "Humans are 10,000 times more common than we should be, according to the rules of the animal kingdom, and we have agriculture to thank for that. Without farming, the world population would probably have reached half a million by now." [18]
Some groups (for example, the World Wide Fund for Nature[19][20] and the Global Footprint Network[21]) have stated that the carrying capacity for the human population has been exceeded as measured using the ecological footprint. In 2006, WWF's "Living Planet" report stated that in order for all humans to live with a high degree of luxury (European standards), we would be spending three times more than what the planet can supply.[22]

But critics question the simplifications and statistical methods used in calculating ecological footprints. Some point out that a more refined method of assessing ecological footprint is to designate sustainable versus non-sustainable categories of consumption.[23][24]
[edit] Resources

David Pimentel,[25] Professor Emeritus at Cornell University, has stated that "With the imbalance growing between population numbers and vital life sustaining resources, humans must actively conserve cropland, freshwater, energy, and biological resources. There is a need to develop renewable energy resources. Humans everywhere must understand that rapid population growth damages the Earth’s resources and diminishes human well-being."[26][27]

These reflect the comments also of the United States Geological Survey in their paper The Future of Planet Earth: Scientific Challenges in the Coming Century. "As the global population continues to grow...people will place greater and greater demands on the resources of our planet, including mineral and energy resources, open space, water, and plant and animal resources." "Earth's natural wealth: an audit" by New Scientist magazine states that many of the minerals that we use for a variety of products are in danger of running out in the near future. "A handful of geologists around the world have calculated the costs of new technologies in terms of the materials they use and the implications of their spreading to the developing world. All agree that the planet's booming population and rising standards of living are set to put unprecedented demands on the materials that only Earth itself can provide. Limitations on how much of these materials is available could even mean that some technologies are not worth pursuing long term.... "Virgin stocks of several metals appear inadequate to sustain the modern 'developed world' quality of life for all of Earth's people under contemporary technology".[28]

On the other hand, some writers, such as Julian Simon and Bjorn Lomborg believe that resources exist for further population growth. However, critics warn, this will be at a high cost to the Earth: "the technological optimists are probably correct in claiming that overall world food production can be increased substantially over the next few decades...[however] the environmental cost of what Paul R. and Anne H. Ehrlich describe as 'turning the Earth into a giant human feedlot' could be severe. A large expansion of agriculture to provide growing populations with improved diets is likely to lead to further deforestation, loss of species, soil erosion, and pollution from pesticides and fertilizer runoff as farming intensifies and new land is brought into production."[29] Since we are intimately dependent upon the living systems of the Earth,[30][31][32] scientists have questioned the wisdom of further expansion.[33]

According to the Millennium Ecosystem Assessment, a four-year research effort by 1,360 of the world’s leading scientists commissioned to measure the actual value of natural resources to humans and the world, "The structure of the world’s ecosystems changed more rapidly in the second half of the twentieth century than at any time in recorded human history, and virtually all of Earth’s ecosystems have now been significantly transformed through human actions."[34] "Ecosystem services, particularly food production, timber and fisheries, are important for employment and economic activity. Intensive use of ecosystems often produces the greatest short-term advantage, but excessive and unsustainable use can lead to losses in the long term. A country could cut its forests and deplete its fisheries, and this would show only as a positive gain to GDP, despite the loss of capital assets. If the full economic value of ecosystems were taken into account in decision-making, their degradation could be significantly slowed down or even reversed."[35][36] The MA blames habitat loss and fragmentation for the continuing disappearance of species.
Another study by the United Nations Environment Programme (UNEP) called the Global Environment Outlook [6] which involved 1,400 scientists and took five years to prepare comes to similar conclusions. It "found that human consumption had far outstripped available resources. Each person on Earth now requires a third more land to supply his or her needs than the planet can supply." It faults a failure to "respond to or recognise the magnitude of the challenges facing the people and the environment of the planet... 'The systematic destruction of the Earth's natural and nature-based resources has reached a point where the economic viability of economies is being challenged - and where the bill we hand to our children may prove impossible to pay'... The report's authors say its objective is 'not to present a dark and gloomy scenario, but an urgent call to action'. It warns that tackling the problems may affect the vested interests of powerful groups, and that the environment must be moved to the core of decision-making... '[37]
Additionally, other issues involving quality of life - would most people want to live in a world of billions more people - and the basic right of other species to exist in their native environments come into play.

[edit] Fresh water
Further information: Water crisis
Fresh water supplies, on which agriculture depends, are running low worldwide.[38][39] This water crisis is only expected to worsen as the population increases. Lester R. Brown of the Earth Policy Institute argues that declining water supplies will have future disastrous consequences for agriculture.[40]

Fresh water can also be obtained from salt water by desalination. For example, Malta derives two thirds of its freshwater by desalination. A number of nuclear powered desalination plants exist,[41] and some argue that there are billions of years of nuclear fuel available.[42] But the high costs of desalination, especially for poor countries, make impractical the transport of large amounts of desalinated seawater to interiors of large countries.[43] However, while desalinizing 1,000 gallons of water can cost as much as $3, the same amount of bottled water costs $7,945. [44]
One study found that "one needs to lift the water by 2000 m, or transport it over more than 1600 km to get transport costs equal to the desalination costs.[citation needed] Desalinated water is expensive in places that are both somewhat far from the sea and somewhat high, such as Riyadh and Harare. In other places, the dominant cost is desalination, not transport. This leads to somewhat lower costs in places like Beijing, Bangkok, Zaragoza, Phoenix, and, of course, coastal cities like Tripoli." Thus while the study is generally positive about the technology for affluent areas that are proximate to oceans, it concludes that "Desalinated water may be a solution for some water-stress regions, but not for places that are poor, deep in the interior of a continent, or at high elevation. Unfortunately, that includes some of the places with biggest water problems."[45]

Israel is now desalinating water for a cost of 53 cents per cubic meter,[46] Singapore at 49 cents per cubic meter.[47] In the United States, the cost is 81 cents per cubic meter ($3.06 for 1,000 gallons). [48]
Another problem of desalination is the "lethal byproduct of saline brine that is a major cause of marine pollution when dumped back into the oceans at high temperatures."[49]

The world's largest desalination plant is the Jebel Ali Desalination Plant (Phase 2) in the United Arab Emirates, which can produce 300 million cubic meters of water per year,[50] or about 2500 gallons per second. The largest desalination plant in the US is the one at Tampa Bay, Florida, which began desalinizing 25 million gallons (95000 m³) of water per day in December 2007.[51] A January 17, 2008, article in the Wall Street Journal states, "Worldwide, 13,080 desalination plants produce more than 12 billion gallons of water a day, according to the International Desalination Association." [52] After being desalinized at Jubail, Saudi Arabia, water is pumped 200 miles (320 km) inland though a pipeline to the capital city of Riyadh. [53]
[edit] Food

Some argue there is enough food to support the world population,[54][55] but other sources dispute this, particularly if sustainability is taken into account.
More than 100 countries now import wheat and 40 countries import rice. Egypt and Iran rely on imports for 40% of their grain supply. Algeria, Japan, South Korea and Taiwan import 70% or more. Yemen and Israel import more than 90%. And just 6 countries - the US, Canada, France, Australia, Argentina and Thailand - supply 90% of grain exports. The US alone supplies almost half of world grain exports.[56][57]
A 2001 United Nations report says population growth is "the main force driving increases in agricultural demand" but "most recent expert assessments are cautiously optimistic about the ability of global food production to keep up with demand for the foreseeable future (that is to say, until approximately 2030 or 2050)", assuming declining population growth rates.[58]
[edit] Global perspective


Growth in food production has been greater than population growth. Food per person increased during the 1961-2005 period.

The amounts of natural resources in this context are not necessarily fixed, and their distribution is not necessarily a zero-sum game. For example, due to the Green Revolution and the fact that more and more land is appropriated each year from wild lands for agricultural purposes, the worldwide production of food had steadily increased up until 1995. World food production per person was considerably higher in 2005 than 1961.[59]

As world population doubled from 3 billion to 6 billion, daily calorie consumption in poor countries increased from 1,932 to 2,650, and the percentage of people in those countries who were malnourished fell from 45% to 18%. This suggests that Third World poverty and famine are caused by underdevelopment, not overpopulation.[60] However, others question these statistics.[61]
The number of people who are overweight has surpassed the number who are undernourished. In a 2006 news story, MSNBC reported, "There are an estimated 800 million undernourished people and more than a billion considered overweight worldwide."[62]

The Food and Agriculture Organization of the United Nations states in its report The State of Food Insecurity in the World 2006, that while the number of undernourished people in the developing countries has declined by about three million, a smaller proportion of the populations of developing countries is undernourished today than in 1990–92: 17% against 20%. Furthermore, FAO’s projections suggest that the proportion of hungry people in developing countries could be halved from 1990-92 levels to 10% by 2015. The FAO also states "We have emphasized first and foremost that reducing hunger is no longer a question of means in the hands of the global community. The world is richer today than it was ten years ago. There is more food available and still more could be produced without excessive upward pressure on prices. The knowledge and resources to reduce hunger are there. What is lacking is sufficient political will to mobilize those resources to the benefit of the hungry." [7]PDF

As of 2008, the price of grain has increased due to more farming used in biofuels,[63] world oil prices at over $100 a barrel,[64] global population growth,[65] climate change,[66] loss of agricultural land to residential and industrial development,[67][68] and growing consumer demand in China and India[69][70] Food riots have recently taken place in many countries across the world.[71][72][73] An epidemic of stem rust on wheat caused by race Ug99 is currently spreading across Africa and into Asia and is causing major concern. A virulent wheat disease could destroy most of the world’s main wheat crops, leaving millions to starve. The fungus has spread from Africa to Iran, and may already be in Afghanistan and Pakistan.[74][75][76]
[edit] Africa
In Africa, if current trends of soil degradation and population growth continue, the continent might be able to feed just 25% of its population by 2025, according to UNU's Ghana-based Institute for Natural Resources in Africa.[77]

Hunger and malnutrition kill nearly 6 million children a year, and more people are malnourished in sub-Saharan Africa this decade than in the 1990s, according to a report released by the Food and Agriculture Organization. In sub-Saharan Africa, the number of malnourished people grew to 203.5 million people in 2000-02 from 170.4 million 10 years earlier says The State of Food Insecurity in the World report.
According to the BBC, the famine in Zimbabwe was caused by government seizure of farmland.[78] However drought has also played a major role.[79] Drought in southern Africa now threatens 13 million people with famine, 6 million of whom live in Zimbabwe.[80] The current food shortages are projected to worsen. [80] Prior to this combination of drought and seizure of farmland, Zimbabwe exported so much food that it was called "the breadbasket of southern Africa". So other countries were also harmed by these farm seizures.[78] People who study the Zimbabwean famine claim that normally there are more than enough natural resources to feed the people.[80][81][82] Some claim that the dams and rivers in Zimbabwe are full, and that the famine has nothing to do with drought.[83] Although it is undoubtedly true that bad governance has exacerbated the famine, the article notes that "Four weeks without rain at the critical germination phase has led to the failure of [the villagers] small crops. There will be no harvest again until next June."

Prior to President Robert Mugabe's seizure of the farmland in Zimbabwe, the farmers had been using irrigation to deal with drought, but during the seizures of the farmland, much of the irrigation equipment was vandalized and looted.[84][85] A 2006 BBC article about the seizure of farmland states, "Critics say the reforms have devastated the economy and led to massive hunger. Much of the formerly white-owned land is no longer being productively used - either because the beneficiaries have no experience of farming or they lack finance and tools. Many farms were wrecked when they were invaded by government supporters."[86]

Compared to Zimbabwe's population density of 33 people per square kilometre, Israel has 302 people per square kilometre.[87] Although Israel is a desert country with frequent drought and very high population density, it does not have famine. One possible reason for this[original research?] is that its government encourages farmers to use modern agriculture and irrigation to grow huge amounts of food.[88][89] Another possible reason is that Israel is a net importer of food.[90] It must also be noted that the high productivity of modern agriculture depends on the unsustainable use of fossil fuels to produce fertilizer and pesticide and to drive farming machinery.[91]

[edit] Asia
In China, only 8% of children are underweight.[92] According to a 2004 article from the BBC, China, the world's most populous country, suffers from an obesity epidemic.[93] More recent data indicate China's grain production peaked in the mid 1990s, due to overextraction of groundwater in the North China plain.[94]

Nearly half of India's children are malnourished, according to recent government data.[citation needed] Japan may face a food crisis that could reduce daily diets to the austere meals of the 1950s, believes a senior government adviser.[95]
[edit] America

According to a 2007 article from the BBC, scientists at Columbia University have theorized that in the future, densely populated cities such as Mexico City, Los Angeles, and New York City, which are the largest in North America, may use vertical farming to grow food on each floor of 30-story skyscrapers.[96]
[edit] Population as a function of food availability

Thinkers such as David Pimentel,[97] a professor from Cornell University, Virginia Abernethy,[98] Alan Thornhill,[99] Russell Hopffenberg[100] and author Daniel Quinn[101] propose that like all other animals, human populations predictably grow and shrink according to their available food supply – populations grow in an abundance of food, and shrink in times of scarcity.

Proponents of this theory argue that every time food production is increased, the population grows. Some human populations throughout history support this theory. Populations of hunter-gatherers fluctuate in accordance with the amount of available food. Population increased after the Neolithic Revolution and an increased food supply. This was followed by subsequent population growth after subsequent agricultural revolutions.

Critics of this idea point out that birth rates are lowest in the developed nations, which also have the highest access to food. In fact, some developed countries have both a diminishing population and an abundant food supply. The United Nations projects that the population of 51 countries or areas, including Germany, Italy, Japan and most of the states of the former Soviet Union, is expected to be lower in 2050 than in 2005.[11] This shows that when one limits their scope to the population living within a given political boundary, human populations do not always grow to match the available food supply. Additionally, many of these countries are major exporters of food.

Nevertheless, on the global scale the world population is increasing,[102] as is the net quantity of human food produced - a pattern that has been true for roughly 10,000 years, since the human development of agriculture. That some countries demonstrate negative population growth fails to discredit the theory. Food moves across borders from areas of abundance to areas of scarcity. Additionally, this hypothesis is not so simplistic as to be rejected by a single case study, as in Germany's recent population trends - clearly other factors are at work: contraceptive access, cultural norms and most importantly economic realities differ from nation to nation.
[edit] As a result of water deficits

Water deficits, which are already spurring heavy grain imports in numerous smaller countries, may soon do the same in larger countries, such as China or India.[103] The water tables are falling in scores of countries (including Northern China, the US, and India) owing to widespread overdrafting beyond sustainable yields. Other countries affected include Pakistan, Iran, and Mexico. This overdrafting is already leading to water scarcity and cutbacks in grain harvest. Even with the overpumping of its aquifers, China has developed a grain deficit. This effect has contributed in driving grain prices upward. Most of the 3 billion people projected to be added worldwide by mid-century will be born in countries already experiencing water shortages. One suggested solution is for population growth to be slowed quickly by investing heavily in female literacy and family planning services.[104] Desalination is also considered a viable and effective solution to the problem of water shortages.[46][47]

After China and India, there is a second tier of smaller countries with large water deficits — Algeria, Egypt, Iran, Mexico, and Pakistan. Four of these already import a large share of their grain. Only Pakistan remains self-sufficient. But with a population expanding by 4 million a year, it will also soon turn to the world market for grain.[105]
[edit] Land

World Resources Institute states that "Agricultural conversion to croplands and managed pastures has affected some 3.3 billion [hectares] — roughly 26 percent of the land area. All totaled, agriculture has displaced one-third of temperate and tropical forests and one-quarter of natural grasslands."[106][107] Energy development may also require large areas; hydroelectric dams are one example. Usable land may become less useful through salinization, deforestation, desertification, erosion, and urban sprawl. Global warming may cause flooding of many of the most productive agricultural areas[108]. Thus, available useful land may become a limiting factor. By most estimates, at least half of cultivable land is already being farmed, and there are concerns that the remaining reserves are greatly overestimated.[109]

High crop yield vegetables like potatoes and lettuce[citation needed] use less space on inedible plant parts, like stalks, husks, vines, and inedible leaves. New varieties of selectively bred and hybrid plants have larger edible parts (fruit, vegetable, grain) and smaller inedible parts; however, many of the gains of agricultural technology are now historic, and new advances are more difficult to achieve. With new technologies, it is possible to grow crops on some marginal land under certain conditions. Aquaculture could theoretically increase available area. Hydroponics and food from bacteria and fungi, like quorn, may allow the growing of food without having to consider land quality, climate, or even available sunlight, although such a process may be very energy-intensive. Some argue that not all arable land will remain productive if used for agriculture because some marginal land can only be made to produce food by unsustainable practices like slash-and-burn agriculture. Even with the modern techniques of agriculture, the sustainability of production is in question.

Some countries, such as the United Arab Emirates and particularly the Emirate of Dubai have constructed large artificial islands, or have created large dam and dike systems, like the Netherlands, which reclaim land from the sea to increase their total land area.[110] Some scientists have said that in the future, densely populated cities will use vertical farming to grow food inside skyscrapers.[96]
The space taken by a humans themselves is not a problem. A number of thinkers who deny that overpopulation is a problem have noted that the whole world population could live on land with the area of Texas. The resources that are apt to run out first are good cropland and fresh water.
[edit] Energy

Population optimists have also been criticized for failing to account for future shortages in fossil fuels, currently used for fertilizer and transportation for modern agriculture. (See Hubbert peak and Future energy development.) They counter that there will be enough fossil fuels until suitable replacement technologies have been developed, for example hydrogen in a hydrogen economy.[111][112]

In his 1992 book Earth in the Balance, Al Gore wrote, "... it ought to be possible to establish a coordinated global program to accomplish the strategic goal of completely eliminating the internal combustion engine over, say, a twenty-five-year period..."[113] Plug-in electric cars such as the Tesla Roadster suggest that Gore's prediction will come true.[citation needed] Earth has enough uranium to provide humans with all of their electricity needs until the sun blows up in 5 billion years, assuming that we develop large-scale breeder reactors.[42]

There has also been increasing development in extracting renewable energy, such as solar, wind, and tidal energy. If used on a wide scale, these could theoretically fulfill most, if not all, of the energy needs currently being filled by non-renewable resources.[citation needed] Most renewable energy forms rely on an oil-based economy to produce, i.e. you cannot make a wind turbine without the oil-run machinery to begin with, making the whole process moot. Some of these renewable resources also have ecological footprints, although they may be different or smaller than some non-renewable resources.

[edit] Fertilizer
Modern agriculture uses large amounts of fertilizer. Since much of this fertilizer is made from petroleum, the problem of peak oil is of concern. According to articles in Discover Magazine (in 2003 and a 2006), it is possible to use the process of thermal depolymerization to manufacture fertilizer out of garbage, sewage, and agricultural waste.[114][115]
[edit] Wealth and poverty


As the world's population has grown, the percentage of the world's population living on less than $1 per day (adjusted for inflation) has halved in 20 years. The graph shows the 1981-2001 period.

The United Nations indicates that about 850 million people are malnourished or starving,[116] and 1.1 billion people do not have access to safe drinking water.[117] Thus some argue that Earth may support 6 billion people, but only if many live in misery. The proportion of the world's population living on less than $1 per day has halved in 20 years, but these are inflation-unadjusted numbers and likely misleading.[118]

The UN Human Development Report of 1997 states: "During the last 15-20 years, more than 100 developing countries, and several Eastern European countries, have suffered from disastrous growth failures. The reductions in standard of living have been deeper and more long-lasting than what was seen in the industrialised countries during the depression in the 1930s. As a result, the income for more than one billion people has fallen below the level that was reached 10, 20 or 30 years ago". Similarly, although the proportion of "starving" people in sub-Saharan Africa has decreased, the absolute number of starving people has increased due to population growth. The percentage dropped from 38% in 1970 to 33% in 1996 and was expected to be 30% by 2010.[61] But the region’s population roughly doubled between 1970 and 1996. To keep the numbers of starving constant, the percentage would have dropped by more than half.[35][119]

Opponents of birth control sometimes argue that overpopulation is unrelated to extreme poverty. [120][121]
The chart to the right is illuminating.


wealth per capita graphed against fertility rate.
As of 2004, there were 108 countries in the world with more than five million people. None of these in which women have, on the average, more than 4 children in their lifetime, have a per capita GDP of more than $5000. Conversely, in all but two of the countries with a per capita GDP of more than $!5,000, women have, on the average, 2 or fewer children in their lifetime. Israel and Saudi Arabia are the only outliers, with per capita GDP between $15,000 and $25,000, and average lifetime births per woman between 2 and 4.
[edit] Environment

Overpopulation has greatly impacted the environment of Earth starting at least as early as the 20th century.[2] There are indirect economic consequences of this environmental degradation in the form of ecosystem services attrition.[122] Beyond the scientifically verifiable harm to the environment, some assert the moral right of other species to simply exist rather than become extinct. Says environmental author Jeremy Rifkin, "our burgeoning population and urban way of life have been purchased at the expense of vast ecosystems and habitats. ... It's no accident that as we celebrate the urbanization of the world, we are quickly approaching another historic watershed: the disappearance of the wild."[123]

Says Peter Raven, former President of the American Association for the Advancement of Science (AAAS) in their seminal work AAAS Atlas of Population & Environment, "Where do we stand in our efforts to achieve a sustainable world? Clearly, the past half century has been a traumatic one, as the collective impact of human numbers, affluence (consumption per individual) and our choices of technology continue to exploit rapidly an increasing proportion of the world's resources at an unsustainable rate. ... During a remarkably short period of time, we have lost a quarter of the world's topsoil and a fifth of its agricultural land, altered the composition of the atmosphere profoundly, and destroyed a major proportion of our forests and other natural habitats without replacing them. Worst of all, we have driven the rate of biological extinction, the permanent loss of species, up several hundred times beyond its historical levels, and are threatened with the loss of a majority of all species by the end of the 21st century."

A 2001 United Nations report has postulated that, although human activity can be blamed for much of the environmental degradation in the last century, overpopulation is not a major cause, but rising per-capita production and consumption and the use of particular technologies used in such production are more likely major factors.[citation needed] Further, even in countries which have both large population growth and major ecological problems, it is not necessarily true that curbing the population growth will make a major contribution towards resolving all environmental problems.[124] However, as developing countries with high populations become more industrialized, pollution and consumption will invariably increase.
[edit] Cities

In 1800 only 3% of the world's population lived in cities. By the 20th century's close, 47% did so. In 1950, there were 83 cities with populations exceeding one million; but by 2007, this had risen to 468 agglomerations of more than one million.[125] If the trend continues, the world's urban population will double every 38 years, say researchers. The UN forecasts that today's urban population of 3.2 billion will rise to nearly 5 billion by 2030, when three out of five people will live in cities.[126]

The increase will be most dramatic in the poorest and least-urbanised continents, Asia and Africa. Surveys and projections indicate that all urban growth over the next 25 years will be in developing countries.[127] One billion people, one-sixth of the world's population, or one-third of urban population, now live in shanty towns,[128] which are seen as "breeding grounds" for social problems such as crime, drug addiction, alcoholism, poverty and unemployment. In many poor countries, slums exhibit high rates of disease due to unsanitary conditions, malnutrition, and lack of basic health care.[129]

In 2000, there were 18 megacities – conurbations such as Tokyo, Mexico City, Mumbai (Bombay), São Paulo and New York City – that have populations in excess of 10 million inhabitants. Greater Tokyo already has 35 million, more than the entire population of Canada.[130]

By 2025, according to the Far Eastern Economic Review, Asia alone will have at least 10 hypercities, those with 20 million or more, including Jakarta (24.9 million people), Dhaka (25 million), Karachi (26.5 million), Shanghai (27 million) and Mumbai (33 million).[131] Lagos has grown from 300,000 in 1950 to an estimated 15 million today, and the Nigerian government estimates that city will have expanded to 25 million residents by 2015.[132] Chinese experts forecast that Chinese cities will contain 800 million people by 2020.[133]

Despite the increase in population density within cities (and the emergence of megacities), UN Habitat states in its reports that urbanization may be the best compromise in the face of global population growth.[134] Cities concentrate human activity within limited areas, limiting the breadth of environmental damage. [135] But this mitigating influence can only be achieved if urban planning is improved[136] and city services are properly maintained.

[edit] Ecological footprint by world region
As set forth on page 18 of WWF's Living Planet report, the regions of the world with the greatest ecological footprint[137] are ranked as follows as of 2003:
1. North America
2. Europe (European Union countries)
3. Middle-East and Central Asia
4. Asia and Pacific Islands
5. Africa
6. Europe (Non-European Union countries)
7. Latin-America and the Caribbean
[edit] Effects of overpopulation
Some problems associated with or exacerbated by human overpopulation:
• Inadequate fresh water[117] for drinking water use as well as sewage treatment and effluent discharge. Some countries, like Saudi Arabia, use energy-expensive desalination to solve the problem of water shortages.[138][139]
• Depletion of natural resources, especially fossil fuels[140]
• Increased levels of air pollution, water pollution, soil contamination and noise pollution. Once a country has industrialized and become wealthy, a combination of government regulation and technological innovation causes pollution to decline substantially, even as the population continues to grow.[141]
• Deforestation and loss of ecosystems[142] that sustain global atmospheric oxygen and carbon dioxide balance; about eight million hectares of forest are lost each year.[143]
• Changes in atmospheric composition and consequent global warming[144] [145]
• Irreversible loss of arable land and increases in desertification[146] Deforestation and desertification can be reversed by adopting property rights, and this policy is successful even while the human population continues to grow.[147]
• Mass species extinctions.[148] from reduced habitat in tropical forests due to slash-and-burn techniques that sometimes are practiced by shifting cultivators, especially in countries with rapidly expanding rural populations; present extinction rates may be as high as 140,000 species lost per year.[149] As of 2007, the IUCN Red List lists a total of 698 animal species having gone extinct during recorded human history.[150]
• High infant and child mortality.[151] High rates of infant mortality are caused by poverty. Rich countries with high population densities have low rates of infant mortality. [8]
• Increased chance of the emergence of new epidemics and pandemics[152] For many environmental and social reasons, including overcrowded living conditions, malnutrition and inadequate, inaccessible, or non-existent health care, the poor are more likely to be exposed to infectious diseases.[153]
• Starvation, malnutrition[116] or poor diet with ill health and diet-deficiency diseases (e.g. rickets). However, rich countries with high population densities do not have famine.[154]
• Poverty coupled with inflation in some regions and a resulting low level of capital formation. Poverty and inflation are aggravated by bad government and bad economic policies. Many countries with high population densities have eliminated absolute poverty and keep their inflation rates very low.[155]
• Low life expectancy in countries with fastest growing populations[156]
• Unhygienic living conditions for many based upon water resource depletion, discharge of raw sewage[157] and solid waste disposal. However, this problem can be reduced with the adoption of sewers. For example, after Karachi, Pakistan installed sewers, its infant mortality rate fell substantially. [158]
• Elevated crime rate due to drug cartels and increased theft by people stealing resources to survive[159]
• Conflict over scarce resources and crowding, leading to increased levels of warfare[160]
[edit] Mitigation measures

While the current world trends are not indicative of any realistic solution to human overpopulation during the 21st century, there are several mitigation measures that have or can be applied to reduce the adverse impacts of overpopulation.
[edit] Birth regulations

See also: Criticism of the Roman Catholic Church#Opposition to contraception
Overpopulation is related to issue of birth control; some nations, like China, use strict measures to reduce birth rates. Religious and ideological opposition to birth control has been cited as a factor contributing to overpopulation and poverty.[161] Some leaders and environmentalists (including Ted Turner) have suggested that there is an urgent need to strictly implement a China-like one-child policy globally by the United Nations, because this would help control and reduce population gradually and most successfully as is evidenced by the success and resultant economic-growth of China due to reduction of poverty in recent years.[162][163] Because such a policy would be uniformly and unanimously implemented globally and would be implemented by a reputable central-global organization (United Nations), it would face little political and social opposition from individual countries.
Indira Gandhi, late Prime Minister of India, implemented a forced sterilization programme in the 1970s. Officially, men with two children or more had to submit to sterilization, but many unmarried young men, political opponents and ignorant men were also believed to have been sterilized. This program is still remembered and criticized in India, and is blamed for creating a wrong public aversion to family planning, which hampered Government programmes for decades.[164]

Urban designer Michael E. Arth has proposed a "choice-based, marketable birth license plan" he calls "birth credits."[165] Birth credits would allow any woman to have as many children as she wants, as long as she buys a license for any children beyond an average allotment that would result in zero population growth (ZPG). If that allotment was determined to be one child, for example, then the first child would be free, and the market would determine what the license fee for each additional child would cost. Extra credits would expire after a certain time, so these credits could not be hoarded by speculators. Another advantage of the scheme is that the affluent would not buy them because they already limit their family size by choice, as evidenced by an average of 1.1 children per European woman. The actual cost of the credits would only be a fraction of the actual cost of having and raising a child, so the credits would serve more as a wake-up call to women who might otherwise produce children without seriously considering the long term consequences to themselves or society.[166]
[edit] Education and empowerment

One option is to focus on education about overpopulation, family planning, and birth control methods, and to make birth-control devices like male/female condoms and pills easily available. An estimated 350 million women in the poorest countries of the world either did not want their last child, do not want another child or want to space their pregnancies, but they lack access to information, affordable means and services to determine the size and spacing of their families. In the developing world, some 514,000 women die annually of complications from pregnancy and abortion. Additionally, 8 million infants die, many because of malnutrition or preventable diseases, especially from lack of access to clean drinking water.[167] In the United States, in 2001, almost half of pregnancies were unintended.[168]

Egypt announced a program to reduce its overpopulation by family planning education and putting women in the workforce. It was announced in June 2008 by the Minister of Health and Population Hatem el-Gabali. The government has set aside 480 million Egyptian pounds (about 90 million U.S. dollars) for the program.[169]
[edit] Extraterrestrial settlement

In the 1970s, Gerard O'Neill suggested building space habitats that could support 30,000 times the carrying capacity of Earth using just the asteroid belt and that the solar system as a whole could sustain current population growth rates for a thousand years.[170] Marshall Savage (1992, 1994) has projected a human population of five quintillion throughout the solar system by 3000, with the majority in the asteroid belt.[171] Arthur C. Clarke, a fervent supporter of Savage, argued that by 2057 there will be humans on the Moon, Mars, Europa, Ganymede, Titan and in orbit around Venus, Neptune and Pluto.[172] Freeman Dyson (1999) favours the Kuiper belt as the future home of humanity, suggesting this could happen within a few centuries.[173] In Mining the Sky, John S. Lewis suggests that the resources of the solar system could support 10 quadrillion (10^16) people.

K. Eric Drexler, famous inventor of the futuristic concept of molecular nanotechnology, has suggested in Engines of Creation that colonizing space will mean breaking the Malthusian limits to growth for the human species.
Many authors (eg. Carl Sagan, Arthur C. Clarke,[174] Isaac Asimov[175]) have argued that shipping the excess population into space is no solution to human overpopulation, and that "the population battle must be fought or won here on Earth". (Clarke, 1999) The problem for these authors is not the lack of resources in space (as shown in books such as Mining the Sky[176]), but the physical impracticality of shipping vast numbers of people into space to "solve" overpopulation on Earth. However, Gerard O'Neill's calculations show that Earth could offload all new population growth with a launch services industry about the same size as the current airline industry in O'Neill, Gerard K. (1981). 2081: A Hopeful View of the Human Future. Simon and Schuster. ISBN 0-671-44751-3..
[edit] Other approaches and effects

Many philosophers, including Thomas Malthus, have said at various times that when humankind does not check population-growth, nature takes its course. But this course might not result in the death of humans through catastrophes; instead it might result in infertility. German scientists have reported that a virus called Adeno-associated virus might have a role in male infertility,[177] but is otherwise harmless to humans.[178] Thus, if this or similar viruses mutate, they might cause infertility on a large-scale, thus resulting in a natural and harmless human population-control over time.

Some[who?] propose that governments around the world should stop spending funds on child vaccination because children would and should survive naturally by principle of "survival of the fittest", rather than artificially through vaccination, and argue that humans survived even before the introduction of modern vaccination. They suggest that the funds saved from vaccination should instead be better spent on providing free-of-cost primary and higher education to everyone, particularly the meritorious but needy scholars and students. Alternatively, they argue that it was only the introduction of modern vaccination that led to the growth in world population from less than 1 billion people to more than 6 billion people in the 20th century only. They argue that saving children who are unable to get proper education leads to unemployment and that such uneducated children gradually become a burden to society and to their nations, and many of them resort to becoming criminals

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Contributed by NguyenDucNam as part of his homework. Thanks Nam.