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南极"小胖子"拯救地球大作战！这些平时被当作鱼饲料卖的浮游动物，每年春天都会上演"深海减肥记"——先把自己吃成圆滚滚的脂肪球，再沉到千米海底慢慢燃烧卡路里。科学家掐指一算：这群"潜水减肥专家"每年锁住的二氧化碳，相当于5500万辆汽车排放量！不过现在它们正面临"中年危机"：海水变暖加上人类捕捞磷虾，让这些"海洋吸碳小能手"的日子越来越难过了～
Tiny creatures gorge, get fat, and help fight global warming
浮游生物"暴食增肥"竟有助于对抗全球变暖
4 July 2025 Share Save Georgina Rannard Climate and science correspondent Share Save
2025年7月4日 气候科学记者乔治娜·兰纳德
Prof Daniel J Mayor @oceanplankton
丹尼尔·J·梅耶教授 @海洋浮游生物
A tiny, obscure animal often sold as aquarium food has been quietly protecting our planet from global warming by undertaking an epic migration, according to new research.
最新研究显示，一种常被当作鱼粮出售的小型浮游动物，正通过壮观的迁徙默默守护地球免受全球变暖影响。
These"unsung heroes" called zooplankton gorge themselves and grow fat in spring before sinking hundreds of metres into the deep ocean in Antarctica where they burn the fat.
这些名为浮游动物的"无名英雄"在春季疯狂进食增肥后，会沉入南极数百米深的海洋燃烧脂肪。
This locks away as much planet-warming carbon as the annual emissions of roughly 55 million petrol cars, stopping it from further warming our atmosphere, according to researchers.
研究人员称，这一过程封存的温室气体相当于5500万辆汽油车的年排放量，有效阻止了大气进一步变暖。
This is much more than scientists expected. But just as researchers uncover this service to our planet, threats to the zooplankton are growing.
这一数字远超科学家预期。但就在揭示这项"地球服务"的同时，浮游生物面临的威胁也在加剧。
Prof Daniel J Mayor @oceanplankton Female copepods (4mm) with cigar-shaped fat stores in their bodies
梅耶教授拍摄的雌性桡足类(4毫米)，体内可见雪茄状脂肪储存
Scientists have spent years probing the animal's annual migration in Antarctic waters, or the Southern Ocean, and what it means for climate change.
科学家们花费数年研究这种动物在南大洋的年迁徙及其对气候变化的意义。
The findings are"remarkable", says lead author Dr Guang Yang from the Chinese Academy of Sciences, adding that it forces a re-think about how much carbon the Southern Ocean stores.
中科院牵头作者杨光博士称这一发现"非凡"，将促使学界重新评估南大洋的碳封存量。
"But the animals are an unsung hero because they have such a cool way of life," says co-author Dr Jennifer Freer from British Antarctic Survey.
"它们的生活方式太酷了，是真正的无名英雄，"英国南极调查局的合著者詹妮弗·弗里尔博士补充道。
Prof Daniel J Mayor @oceanplankton This copepod has hair-like arms for feeding
梅耶教授拍摄的桡足类，可见用于摄食的毛发状附肢
If anyone has heard of them, it's probably as a type of fish food available to buy online.
即便有人听说过它们，多半也是作为网购鱼粮。
But their life cycle is odd and fascinating. Take the copepod, a type of zooplankton that is a distant relative of crabs and lobsters.
但其生命周期奇妙而迷人。以桡足类为例，这种浮游动物是螃蟹和龙虾的远亲。
Just 1-10mm in size, they spend most of their lives asleep between 500m to 2km deep in the ocean.
体长仅1-10毫米的它们，一生大部分时间都在500米至2千米的深海中"沉睡"。
Prof Daniel J Mayor @oceanplankton Sacs of fat, or lipids, form in Southern Ocean copepods' bodies and heads after they eat phytoplankton (the green material in the bodies in this image)
梅耶教授拍摄的南大洋桡足类，摄食浮游植物(体内绿色物质)后形成脂肪囊
In pictures taken under a microscope, you can see long sausages of fat inside their bodies, and fat bubbles in their heads, explains Prof Daniel Mayor who photographed them in Antarctica.
在南极拍摄这些生物的梅耶教授解释，显微镜照片可见它们体内的"脂肪香肠"和头部的"脂肪泡泡"。
Without them, our planet's atmosphere would be significantly warmer. Globally the oceans have absorbed 90% of the excess heat humans have created by burning fossil fuels.
若没有它们，地球大气将显著变暖。全球海洋已吸收人类燃烧化石燃料产生的90%余热。
Of that figure, the Southern Ocean is responsible for about 40%, and a lot of that is down to zooplankton.
其中约40%由南大洋吸收，浮游动物功不可没。
Prof Daniel J Mayor @oceanplankton
梅耶教授的浮游生物采样工作照
Millions of pounds is being spent globally to understand how exactly they store carbon.
全球正投入数百万英镑研究其碳储存机制。
Scientists were already aware that the zooplankton contributed to carbon storage in a daily process when the animals carbon-rich waste sinks to the deep ocean.
科学家已知浮游动物通过富含碳的排泄物沉入深海实现日常碳封存。
But what happened when the animals migrate in the Southern Ocean had not been quantified.
但其在南大洋迁徙时的碳封存一直未被量化。
The latest research focussed on copepods, as well as other types of zooplankton called krill, and salps.
最新研究聚焦桡足类及磷虾、樽海鞘等其他浮游动物。
The creatures eat phytoplankton on the ocean surface which grow by transforming carbon dioxide into living matter through photosynthesis.
它们摄食海表浮游植物——后者通过光合作用将二氧化碳转化为生物质。
This turns into fat in the zooplankton.
这些物质在浮游动物体内转化为脂肪。
"Their fat is like a battery pack. When they spend the winter deep in the ocean, they just sit and slowly burn off this fat or carbon," explains Prof Daniel Mayor at University of Exeter, who was not part of the study.
"脂肪如同电池组。当它们在深海越冬时，就慢慢燃烧这些脂肪碳，"埃克塞特大学的梅耶教授比喻道。
"This releases carbon dioxide. Because of the way the oceans work, if you put carbon really deep down, it takes decades or even centuries for that CO2 to come out and contribute to atmospheric warming," he says.
"释放的二氧化碳因深海环流特性，需数十年甚至数百年才能重返大气。"
Jennifer Freer Dr Jennifer Freer analyzed the zooplankton on board the Sir David Attenborough polar ship
弗里尔博士在"大卫·爱登堡爵士号"极地船上分析浮游生物
The research team calculated that this process - called the seasonal vertical migration pump - transports 65 million tonnes of carbon annually to at least 500m below the ocean surface.
研究团队计算得出，这种"季节性垂直迁移泵"每年将6500万吨碳输送至至少500米深的海底。
Of that, it found that copepods contribute the most, followed by krill and salps.
其中桡足类贡献最大，其次是磷虾和樽海鞘。
That is roughly equivalent to the emissions from driving 55 million diesel cars for a year, according to a greenhouse gas emissions calculator by the US EPA.
据美国环保署计算器，这相当于5500万辆柴油车年排放量。
Prof Daniel J Mayor @oceanplankton Plankton sampling often happens at midnight when the animals are closest to the ocean surface.
梅耶教授拍摄的午夜浮游生物采样场景
The latest research looked at data stretching back to the 1920s to quantify this carbon storage, also called carbon sequestration.
这项研究追溯至1920年代的数据来量化这种"碳封存"。
But the scientific discovery is ongoing as researchers seek to understand more details about the migration cycle.
随着对迁徙周期研究的深入，科学发现仍在持续。
Earlier this year, Dr Freer and Prof Mayor spent two months on the Sir David Attenborough polar research ship near the South Orkney island and South Georgia.
今年初，弗里尔博士和梅耶教授在"大卫·爱登堡爵士号"极地船上进行了为期两个月的考察。
Using large nets the scientists caught zooplankton and brought the animals onboard.
科学家用大型网具捕捞浮游生物进行研究。
"We worked in complete darkness under red light so we didn't disturb them," says Dr Freer.
"我们在红光下的全黑环境中工作，以免惊扰它们，"弗里尔博士描述道。
"Others worked in rooms kept at 3-4C. You wear a lot of protection to stay there for hours at a time looking down the microscope," she adds.
"有些同事在3-4℃的实验室工作，需全副武装在显微镜前连续观察数小时。"
Prof Daniel J Mayor @oceanplankton Antarctic krill (50-60mm) with green guts showing they've recently eaten algae
梅耶教授拍摄的南极磷虾(50-60毫米)，绿色肠道显示刚摄食藻类
But warming waters as well as commercial harvesting of krill could threaten the future of zooplankton.
但海水变暖和磷虾商业捕捞正威胁浮游生物的未来。
"Climate change, disturbance to ocean layers and extreme weather are all threats," explains co-author Prof Angus Atkinson from Plymouth Marine Laboratory.
"气候变化、海洋层扰动和极端天气都是威胁，"合著者安格斯·阿特金森教授指出。
This could reduce the amount of zooplankton in Antarctica and limit the carbon stored in the deep ocean.
这将减少南极浮游生物数量，限制深海碳封存。
Krill fishing companies harvested almost half a million tonnes of krill in 2020, according to the UN.
据联合国数据，2020年磷虾捕捞量近50万吨。
It is permitted under international law, but has been criticised by environmental campaigners including in the recent David Attenborough Ocean documentary.
虽然国际法允许，但环保人士在纪录片中批评了这一行为。
The scientists say their new findings should be incorporated into climate models that forecast how much our planet will warm.
科学家建议将新发现纳入预测全球变暖的气候模型。
"If this biological pump didn't exist, atmospheric CO2 levels would be roughly twice those as they are at the moment. So the oceans are doing a pretty good job of mopping up CO2 and getting rid of it," explains Prof Atkinson.
"若没有这种生物泵，大气二氧化碳浓度将是现在的两倍。海洋在吸收清除二氧化碳方面做得很好，"阿特金森教授解释道。
The research is published in the journal Limnology and Oceanography.
该研究发表于《湖沼学与海洋学》期刊。
