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。4 t! r$ S9 P; m( A
) L1 Q6 c/ _5 T: y A satellite image has revealed the scale of a vast algal bloom spreading in the Baltic Sea.* A* P9 A2 _& M9 x" d* d
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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.: p: r+ t3 k" b" ?5 l2 S8 k+ V' W* [
9 A2 J! A. {/ I4 a* M6 D They added that a lack of wind and prolonged high temperatures had triggered the largest bloom since 2005.
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The affected area stretches from Finland in the north to parts of Germany and Poland in the south.5 u. V5 r; P1 l7 M2 P/ q
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The image, captured earlier this month, was recorded by a camera on the European Space Agency's Envisat satellite.$ @) I3 d4 y8 k# V/ W+ w% F
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Researchers monitoring the spread of the blue-green algae said such blooms had spread over the Baltic Sea each summer for decades.
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R) {5 H0 D2 ]4 f: A* G They added that fertilizers from surrounding agricultural land were being washed into the sea and exacerbating the problem." v) L; w7 H' W/ Y4 l# x
6 ^. K5 e- b, D' [ This has led to a process called eutrophication, in which the additional nutrients stimulate rapid growth of phytoplankton - microscopic free-floating marine plants.
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0 s& v1 g8 F/ k: v. p 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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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.4 r+ j4 r1 O% v3 p- i; S; b
( f9 e+ S& O! H, ~ However, researchers said the current bloom would quickly break up with the arrival of strong winds, as the resulting waves would disperse the algae. |