Читать книгу Practical Sustainability Strategies - George P. Nassos - Страница 40

This means that we cannot harvest or manipulate ecosystems in such a way that productive capacity, ecosystem services, and diversity systematically diminish. While the first two system conditions refer to generation of substances into the ecosphere, this condition pertains to the destruction of the natural resources in such a way or to an extent that they cannot regenerate and be useful. An example is the over harvesting of forests to meet the current demand for wood, or for its conversion to paper. This also has a detrimental effect in reducing the sequestration of carbon dioxide. Human activities need to work in harmony with the cyclic principle of nature. Carbon dioxide emitted as a result of the combustion of fossil fuels is absorbed by vegetation and returned to the earth's ecosphere. Overharvesting to meet the current demand may make it impossible for future generations to meet their requirements.

Other examples include the destruction of forests to convert the land for agricultural use. The increase in demand for food has forced some nations to trade off forests for agricultural land. This condition can also be considered in violation for the production of ethanol from corn. The land needed for this industrial crop could also be used for food crops. Overharvesting of fish may eventually deplete the fish population to a level below which regeneration to its original level may be impossible.