It has been estimated that the total human population of the world was less than 20 million in 6000 B.C. During the next 7,750 years, it rose to 500 million; by 1850, it had doubled to 1 billion; and 70 years later, it had doubled again to 2 billion. The 4.48-billion mark was reached in 1980, and within 5 years, it had grown to 4.89 billion. It is presently increasing by nearly 80 million annually, and estimates for the year 2006 are over 6.5 billion. By 2025 it is believed the world’s population will exceed 7.8 billion. The earth remains constant in size, but humans obviously have occupied a great deal more of it over the past few centuries or at least have greatly increased in density of population.
In feeding, clothing, and housing ourselves, we have had a major impact on our environment. We have drained wetlands and cleared natural vegetation from vast areas of land. California, for example, now has less than 5% of the wetland it had 100 years ago. We have dumped wastes and other pollutants into rivers, oceans, lakes, and added pollutants to the atmosphere, and we have killed pests and plant disease organisms with poisons. These poisons have also killed natural predators and other useful organisms, and, in general, have thoroughly disrupted the delicate balance of nature that existed before humans began degrading their natural surroundings.
If we are to survive on this planet beyond the 21st century, there is little question that humans have to stop increasing in numbers, and the many unwise agricultural and industrial practices that have accompanied the mushrooming of human populations must be replaced with practices more in tune with restoring some ecological balance. Agricultural practices of the future will have to include the return of organic material to the soil after each harvest, instead of adding only inorganic fertilizers. Harvesting of timber and other crops will have to be done in a manner that prevents topsoil erosion, and the practice of clearing brush with chemicals will have to be abolished. Industrial pollutants will have to be rendered harmless and recycled whenever possible.
Many products that now are still largely discarded (e.g., garbage, paper products, glass, metal cans) will also have to be recycled on a much larger scale. Biological controls will have to replace the use of poisonous controls whenever possible. Water and energy conservation will have to be universally practiced, and rare plant species, with their largely unknown gene potential for future crop plants, will need to be saved from extinction by preservation of their habitats and by other means. The general public will have to be made even more aware of the urgency for wise land management and conservation—which will be especially needed when pressures are exerted by influential forces promoting unwise measures in the name of “progress”—before additional large segments of our natural resources are irreparably damaged or lost forever.
Alternatives appear to be nothing less than death from starvation, respiratory diseases, poisoning of our food and drink, and other catastrophic events that could ensure the premature demise of large segments of the world’s population.In recent years, scientists and, increasingly, the general public, have become alarmed about the effects of human carelessness on our environment. It wasn’t until the 1980s,shield, major global climatic changes, loss of biodiversity in general, and loss of tropical rain forests in particular, gained widespread publicity. However, that damage to forests and lakes caused by acid rain, the “greenhouse effect,” contamination of ground water by nitrates and pesticides, reduction of the ozone shield, major global climatic changes, loss of biodiversity in general, and loss of tropical rain forests in particular, gained widespread publicity.
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