近年来,全球各地的人们都在极端天气下饱受煎熬,酷暑、严寒、洪水、强风……事实上,如果人类再继续肆无忌惮的破坏地球环境的话,人类将为自己的行为付出更大的代价。
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A satellite image has revealed the scale of a vast algal bloom spreading in the Baltic Sea./ q5 K. r3 W8 Z: _ @: B2 e' L
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The potentially toxic bloom, covering 377,000 sq km, could pose a risk to marine life in the region, warn scientists. f7 O% q2 U/ n' {2 @
% h* ]9 z8 J7 s7 |, q! F3 G; y They added that a lack of wind and prolonged high temperatures had triggered the largest bloom since 2005.1 q$ x2 @2 C3 l+ a2 q! c- S
0 \3 Z& z! t% O j The affected area stretches from Finland in the north to parts of Germany and Poland in the south.
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The image, captured earlier this month, was recorded by a camera on the European Space Agency's Envisat satellite.& N" j0 f7 e) T1 w {
- _+ W1 o/ g! i; P/ ] J3 ] Researchers monitoring the spread of the blue-green algae said such blooms had spread over the Baltic Sea each summer for decades.% P2 s2 Z. {# }# _3 W
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They added that fertilizers from surrounding agricultural land were being washed into the sea and exacerbating the problem.' I( k2 e7 w# X3 c
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This has led to a process called eutrophication, in which the additional nutrients stimulate rapid growth of phytoplankton - microscopic free-floating marine plants.$ ^2 |* ], G5 U! l, l6 b, x
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This accelerated growth also reduces the amount of oxygen available to other plant and animal species in the affected area; raising fears that it could destabilise fragile marine ecosystems.
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9 ]" Z" K, h0 f h/ u7 e As well threatening certain species, blue-green algae can also pose a risk to human health, and officials are advising people not to bathe in areas where the algae is visible.
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However, researchers said the current bloom would quickly break up with the arrival of strong winds, as the resulting waves would disperse the algae. |