onsdag 20 februari 2008

Ronald Bailey om överkonsumtion

Ronald Bailey hos Reason skriver om överkonsumtion. Några utdrag:

World population increased from about 1.5 billion in 1900 to 6.5 billion today. Along the way, Malthusians predicted that massive famines would occur. They didn't. Food supplies increased faster than population growth and food became cheaper and more abundant. In addition, the amount of land devoted to farming barely changed. As a consequence of growing food security and the spread of improved public health and medical technologies, global human life expectancy more than doubled.

A 2006 study published in the Proceedings of the National Academy of Sciences found that "among 50 nations with extensive forests reported in the Food and Agriculture Organization's comprehensive Global Forest Resources Assessment 2005, no nation where annual per capita gross domestic product exceeded $4,600 had a negative rate of growing stock change." Biotech tree plantations would enable humanity to produce all the timber we need on an area roughly 5 percent to 10 percent of the total forest today. [Det skrev jag om här.]

Similarly, the amount of land needed to grow enough food to feed a person has plummeted from about one-and-a-quarter acres in 1950 to about half an acre today. Jesse Ausubel, director of the Program for the Human Environment at Rockefeller University, finds, "If the world farmer reaches the average yield of today's US corn grower during the next 70 years, ten billion people eating as people now on average do will need only half of today's cropland.

Americans are using less water per capita too. Water withdrawals peaked in 1980 and have been flat since. All kinds of innovative techniques for stretching freshwater supplies are being developed. An example of that is the low-cost drip irrigation systems designed by International Development Enterprises that can reduce the cost of irrigation in poor countries from about $6,000 per acre to about $37.


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