Population Growth And Its Impacts

1. Population through ages
2. Rapid growth of population in 20th century due to variation in death & birth rates
3. The most populated countries
4. The speed of population growth
5. Stress on grain production
6. Cropland
7. Scarcity of fresh water
8. Diminishing of oceanic fish catch
9. Limiting meat production
10. Natural Reaction Areas
11. Killing of forest
12. Threat to biodiversity
13. Climate change – a serious hazard
14. Energy shortage
15. Waste problem
16. Rapid increase in unemployment
17. Income distribution
18. Housing & education problem
19. Urbanization
20. Conclusion

During the first 2 million or so years of is history the human population was a minor element in the world ecosystem, with at most 10 million members. In the New Stone Age, less than 10,000 years ago, the numbers of humans began to increase more rapidly. The rough equilibrium maintained before Neolithic times gave way the human population developed agriculture and animal husbandry and no longer had to spread out in search of game. With the abandonment of a hunting-gathering way of life and the rise of permanent settlement and eventually cities, the human population underwent dramatic growth. By the beginning of the Christian era it had reached 250 million, and by 1650, half a billion.

Growth of population during 20th century was very rapid. In 1994 the total world population was estimated at about 5.6 billion people. It increased nearly by 4 billion of people during past 100 years. The most significant world trend is that death rates are currently falling in poor and rich countries alike, while birth rates remain high in most poor countries and low in most rich ones. Exceptions are the generally higher death rates of Africa and the high birth rates of the rich oil-producing countries.

The world’s population has doubled during the last half century, climbing from 2.5 billion in 1998. This unprecedented surge in population, combined with rising individual consumption, is pushing our claims on the planet beyond its natural limits.

The United Nations projects that human Population in 2050 will range between 7.7 billion and 11.2 billion people. We use the United Nations middle-level projection of 9.4 billion (from world Population Prospects) to give an idea of the strain this “most likely” outcome would peace on ecosystems and governments in the future and of the urgent need to break from the business-as-usual scenario. This essay look at 16 dimensions or effects of population growth in order to gain a better perspective on how future population trends are likely to affect human prospects: From 1950 to 1984, growth in the world grain harvest easily exceeded that of population, so per-person output has dropped by 7% (0.5% a year), according to the U.S. Department of Agriculture.

The slower growth in the world grain harvest since 1984 is due to the lack of new land and to slower growth in irrigation and fertilizer use because of the diminishing of these inputs.

Now that the frontiers of agriculture settlement have disappeared, future growth in the grain production must come almost entirely from raising land productivity. Unfortunately, this is becoming more difficult. The challenge for the world’s farmers is to reverse this decline at a time when cropland area per person is shrinking, the amount of irrigation water per person is dropping, and the crop yield response to additional fertilizers use is falling.

Since mid-century, grain area- which serves as a proxy for cropland in general – has increased by some 19%, but global population has grown by 132%. Population growth can degrade farmland, reducing or even eliminating it from production. As grain area per person falls, more and more nations risk losing the capacity to feed themselves.

The trend is illustrated starkly in the world’s four fastest-growing large countries. Having already seen per capita grain area shrink by 40%-50% and 1998, Pakistan, Nigeria, Ethiopia, and Iran except a further 60%-70% loss by 2050 – a conservative projection that assumes no further losses of agricultural land. The result will be four countries with a combined population of more than 1 billion whose grain area per person will be only 300-600 square meters –less than a quarter of the area in 1950.

Spreading water scarcity may be the most underrated resource issue in the world today. Whenever population is growing, the supply of fresh water per person is declining. Evidence of water stress can be seen as rivers are drained dry and water tables fall. Rivers such as the Nile, the Yellow, and the Colorado have little water left when they reach the sea. Water tables are now falling on every continent, including in major food-producing regions

The International water Management Institute projects that a billion will be living in countries facing absolute water scarcity by 2025. These countries will have to reduce water use in agriculture in order to satisfy residential and industrial water needs. In both China AND India, the two countries that together dominate water supplies lie ahead.

A fivefold growth in the human appetite for seafood since 1950 has pushed the catch of most oceanic fishers to their sustainable limits or beyond. Marine biologists believe that the oceans cannot sustain an annual catch of much more than 93 million tons, the current take.

As we near the end of the twentieth century, over-fishing has become the rule, not the exception. Of the 15 major oceanic fisheries, 11 are in decline. The catch of Atlantic cod – long a dietary mainstay for western Europeans – has fallen by 70% since peaking in 1968. Since 1970, Bluefin tuna in the West Atlantic have dropped by 80%.

With the oceans now pushed to their limits, future growth in the demand for seafood can be satisfied only by fish farming. But as the world turns to aquaculture to satisfy its needs, fish begin to compete with livestock and poultry for feedstuffs such as grain, soybean meal, and fish meal.

The next half century is likely to be marked by the disappearance of some species from markets, a decline in the quality of seafood caught, higher prices, and more conflicts among countries over access to fisheries. Each year, the future oceanic catch per person will decline by roughly the amount of population growth, dropping to 9.9 kilograms (22pounds) per person in 2050, compared with the 1988 peak of 17.2 kilograms (37.8) pounds). When incomes being to rise in traditional low-income societies, one of the first things people do is diversify their diets, consuming more livestock products.

World meat production since 1950 has increased almost twice as fast as population. Growth in meat production was originally concentrated in western industrial countries and japan, but over the last two decades it has increased rapidly in East Asia, the Middle East and Latin American. Beef, pork, and poultry account for the bulk of world consumption. Of the world grain harvest of 1.87, an estimated 37% will be used to feed livestock and poultry, producing milk and eggs as well as meat, according to the U.S. Department of Agriculture. Grain feed to livestock and poultry is now the principle food reserve in the event of a world food emergency.

Total meet communication will rise from 211 million tons in 1997 to 513 million tons in 2050, increasing pressures on the supply of grain.

The ultimate manifestation of population growth outstripping the supply of housing is homelessness. The United Nations estimates that at least 100 million of the world’s people – roughly equal to the population of Mexico-have no more; the number tops 1 billion of squatters and other with insecure or temporary accommodation are included. Unless population growth can be checked worldwide, he ranks of the homeless are likely to swell dramatically.

If national education systems begin to stress lifelong learning for a rapidly changing world of the twenty-first century, then extensive provision for adult education will be necessary, affecting even those countries with shrinking child-age populations.

Such a development means that countries which started population-stabilization programs earliest will be in the best position to educate their entire citizenry. Today’s cities are growing faster: It took London 130 years to get from 1 million inhabitants; Mexico City this jump in just 30 years. The world’s urban population as a whole is growing by just over 1 million people each week. This urban growth is fed by the natural increase of urban populations, by ne migration from the country-side, and by villages or towns expanding to the point where they are absorbed by the spread of existing cities. If recent continue, 6.5 billion people will live in cities by 2050, more than the world’s total population today.

Actions for Slowing Growth: As we look to the future, the challenge for the world leaders is to help countries maximize the prospects for achieving susceptibility by keeping both birth and death rates low. In a world where both grain output and fish catch per person are falling, a strong case can be made on humanitarian grounds to stabilize world population.