Word: manned
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Dates: during 1970-1979
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...like bulldozers, making natural irrigation channels. Without the animals, the rivers quickly silted up; without the overflow channels, periodic floods swept like scythes over adjacent lands. The altered conditions favored a proliferation of schistosomiasis-carrying water snails. Such harsh intrusions on wildlife constitute only one way in which man abuses nature. Another is through his sheer numbers. From an estimated 5,000,000 people 8,000 years ago, the world population rose to 1 billion by 1850, 2 billion about 1930, and now stands at 3.5 billion. Current projections run to 7 billion by the year 2000. Neo-Malthusians like...
Modern technology is already pressuring nature with tens of thousands of synthetic substances, many of which almost totally resist decay?thus poisoning man's fellow creatures, to say nothing of himself. The burden includes smog fumes, aluminum cans that do not rust, inorganic plastics that may last for decades, floating oil that can change the thermal reflectivity of oceans, and radioactive wastes whose toxicity lingers for literally hundreds of years. The earth has its own waste-disposal system, but it has limits. The winds that ventilate earth are only six miles high; toxic garbage can kill the tiny organisms that...
...Man's inadvertence has even upset the interior conditions of the earth's crust. One of the most respected U.S. geophysicists, Gordon J. F. MacDonald, reports that wherever huge dams are built, the earth starts shuddering. The enormous weight of the water in the reservoirs behind the dam puts a new stress on the subsurface strata, which are already in natural stress. In consequence, giant sections of the earth's crust sheer past one another and the earth quivers. MacDonald warns that earthquakes may result (and did near Denver) from one of the newest anti-pollution techniques: injecting liquid chemical...
...technology got man into this mess, surely technology can get him out of it again. Not necessarily, argues Anthony Wiener of the Hudson Institute. Wiener sees technological man as the personification of Faust, endlessly pursuing the unattainable. "Our bargain
...technology to cure pollution, his medicine may well have side effects. Consider his $10 billion plan to build new primary and secondary municipal water-treatment plants. While such plants do make water cleaner, they also have two serious faults. Unlike more expensive tertiary treatment plants, they do not exterminate man-killing viruses, like those that cause infectious hepatitis. They also convert organic waste into inorganic compounds, especially nitrates and phosphates. When these are pumped into rivers and lakes, they fertilize aquatic plants, which flourish and then die. Most of the dissolved oxygen in the water is used up when they...