题型:阅读理解 题类:模拟题 难易度:普通
吉林省长春市2020届高三质量监测(四模)英语
A few weeks ago, scientists at Ukraine's Vernadsky Research Base in Antarctica found their usually white surrounds were covered in a shocking blood-red. For such a mess, the culprits behind this horrible scene are tiny.
"Our scientists have identified them under a microscope as Chlamydomonasnivalis (雪地 衣藻) said the National Antarctic Scientific Centre of Ukraine in a Facebook post.
These green algae (藻类) . a type of seaweed, are common in all icy and snowy regions of Earth, from the Arctic to high mountain regions. They lie still during the freezing winter, but once the sunlight warms enough to soften their world, the algae awake, making use of the melt water and sunlight to rapidly bloom (开花) .
"The algae need liquid water in order to bloom," University of Leeds microbiologist Steffi Lutz told Gizmodo in 2016. "The algal blooms contribute to climate change," the center stated.
A study in 2016 showed that snow algal blooms can decrease the amount of light reflected from the snow by up to 13 percent across one melt season in the Arctic. "This will surely result in higher melt rates,” the researchers wrote.
In 2017 environmental scientists calculated that microbial (微生物的) communities contributed to over a sixth of the snowmelt where they were present in Alaskan ice fields. Their experiments showed that areas with more melt water led to the growth of 50 percent more algae and places with more algae melted further.
This Antarctic summer has certainly seen a lot more melt water than usual. Temperature records keep changing, leading to rapid melting previously only seen in the Northern Hemisphere (半球) .
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