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全球化对环境影响的争议

Global change has become a popular word in scientific debates on long-range

structural change in the earth‟s ecology. Globalization has in the past played a

major role in the controversial environmental debates. Many problems resulted in

this area of discussion, in regard to the intricate linkages between

globalization, government, trade and transport, and environmental decay. The

current debate on the environmental effects of globalization is particularly

concerned with the question whether a worldwide liberalization of trade may

provoke environmental collapse. Three major environmental concerns related to

trade are the domestic environmental effects caused by the use of imported

products, the foreign environmental effects caused by the production of exported

goods, and the environmental effects caused by transport movements needed for

international trade.

危害健康的颗粒污染物

Particulate matter (soot, ash, and other solids), usually consist of unburned

hydrocarbons, carbon monoxide, sulfur dioxide, various nitrogen oxides, ozone,

and lead. These compounds undergo a series of chemical reactions in the presence

of sunlight: the result is smog (a term used to describe a noxious mixture of

fog and smoke).

The process by which these pollutants harm our bodies begins by simply taking

a breath. Particulates are present everywhere, in some areas they are as dense

as 100,000 per milliliter of air. The damage begins when the particulates are

inhaled into the small air sacs of our lungs called alveoli. With densities such

as 100,000 per milliliter a single alveolus may receive 1,500 particulates per

day. These particulates cause the inflammation of the alveoli. The inflammation

causes the body to produce agents in the blood that increase clotting ability,

which leads to the decreased functionality of the cardiovascular system,

resulting in diseases and increased mortality.

基因污染

Purebred naturally evolved region specific wild species can be threatened

with extinction in a big way through the process of Genetic Pollution, i.e.

uncontrolled hybridization, introgression and Genetic swamping which leads to

homogenization or replacement of local genotypes as a result of either a

numerical and/or fitness advantage of introduced plant or animal. Nonnative

species can bring about a form of extinction of native plants and animals by

hybridization and introgression either through purposeful introduction by humans

or through habitat modification, bringing previously isolated species into

contact. These phenomena can be especially detrimental for rare species coming

into contact with more abundant ones where the abundant ones can interbreed with

them swamping the entire rarer gene pool creating hybrids thus driving the

entire original purebred native stock to complete extinction. Attention has to

be focused on the extent of this underappreciated problem that is not always

apparent from morphological (outward appearance) observations alone. Some degree

of gene flow may be a normal, evolutionarily constructive process, and all

constellations of genes and genotypes cannot be preserved however. Hybridization

with or without introgression may, nevertheless, threaten a rare species‟

existence.