Barrons AP Environmental Science

(Marvins-Underground-K-12) #1

■ COASTLINES AND OCEANS: Half of all coastal ecosystems are pressured by
high population densities and urban development. Ocean fisheries are
being overexploited, estuaries (nurseries of the sea) are being drained and
filled in because of population growth, and fish catches are down.


■ FORESTS: Nearly half of the world’s original forest cover has been lost,
and each year another 16 million hectares are cut, bulldozed, or burned.
Forests provide over $400 billion to the world economy annually and are
vital to maintaining healthy ecosystems. Yet, the current demand for forest
products may exceed the limit of sustainable consumption by 25%.


■ FOOD SUPPLY AND MALNUTRITION: Today, one-quarter of the world’s
population is malnourished. In 64 of 105 developing countries, most
notably in Africa, Asia, and parts of Latin America, the population has
been growing faster than available food supplies. Population pressures
have also degraded some 2 billion hectares of arable land—an area the
size of Canada and the United States combined.
The issue is not that the world does not produce enough food. The
issue is that too many people cannot afford food and that it is not
distributed equally. If all food grown and raised on Earth was distributed
equally, it would result in 4.3 pounds (2 kg) of food per person per day.
Advances made during the first and second green revolutions, which
focused on increasing food production, have not ended world famine and
malnutrition. Even though poorer countries (e.g., India, the Philippines,
and many African countries) have been able to increase their food
production through technological improvements, the food production
(often by large, foreign, multinational corporations whose motivation is
profit) is often sold to other wealthier countries that are able to pay higher
prices.

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