红色液体从白色的冰川上流淌下来，这一景象看起来就像电影中的场景，但实际上却是真实存在的。这种现象被称为“血瀑布”（Blood Falls），它位于南极洲。根据2026年发表在《自然·地球科学》（Nature Geoscience）杂志上的一项研究，研究人员通过对该地区的基因分析，发现了一种与泰勒冰川（Taylor Glacier）下方的咸水环境相关的海洋微生物群落。这种微生物群落似乎在与海洋隔绝后仍然存活了很长时间。
A red stain flowing down a white glacier might look like a movie scene, but it is real. It is called Blood Falls, and it is in Antarctica. According toa 2026 Nature Geoscience study, genetic clues from this site led researchers to a marine microbial community associated with the brine below Taylor Glacier. The community appears to have survived for a long time after being cut off from the ocean. The red brine and the ancient sea beneath itBlood Falls pours out from the end of the Taylor Glacier in the McMurdo Dry Valleys. The water is red and salty, and it is full of iron. It runs down the slope and flows into Lake Bonney.
“血瀑布”中的红色液体实际上是一种含铁量极高的咸水，它从泰勒冰川的末端流出，最终汇入邦尼湖（Lake Bonney）。早期的研究已经为这种咸水的起源提供了一些线索：据推测，这种咸水形成于温暖时期，当时海水淹没了泰勒山谷，后来随着冰川的不断推进，这些海水被封闭在了山谷中。在2019年发表于《地球物理研究杂志：生物地球科学》（Journal of Geophysical Research: Biogeosciences）的一篇论文中，莱昂斯（Lyons）及其同事提供了进一步的证据，证明这些咸水中的溶解物质来源于古代的海水。
Previous studies provided some clues to the origin of this brine. They suggest it formed when seawater flooded Taylor Valley during warm periods, before the advancing glacier trapped it. In a 2019 paper in the Journal of Geophysical Research: Biogeosciences, Lyons and colleagues presented evidence that the dissolved material in the brine came from ancient seawater. The team took samples of brine from a channel within the glacier in 2014. In the 2026 paper, the team analyzed 167 water, sediment, and wind-blown samples from the Dry Valleys and from marine sites.
研究团队在2014年从冰川内部采集了样本，并在2026年的研究中分析了来自干谷地区（Dry Valleys）以及海洋地区的167份水样、沉积物样本和风蚀沉积物样本。其中，海洋样本包括2015年从麦克默多海峡（McMurdo Sound）采集的海冰和海水。
The marine samples included sea ice and seawater from McMurdo Sound that were collected earlier, in 2015. At the end of the glacier, they found a distinct community of marine microorganisms living only in the red ice, mud, and sediment. Many of them were diatoms, minute algae. Others were haptophytes, dinoflagellates, and ciliates.
研究发现，红色沉积物中的藻类（主要是硅藻）中有超过60%属于海洋物种；而其他干谷地区的溪流和湖泊中则主要含有淡水藻类，其中海洋来源的硅藻仅占1.5%。此外，研究还发现许多微生物属于鞭毛藻（dinoflagellates）、甲藻（haptophytes）和纤毛虫（ciliates）等类型。这些基因证据表明，这些海洋微生物群落确实是在与海洋隔绝的环境中独立演化而来的。
What the genetic evidence indicatesThe numbers were striking. More than 60 percent of the diatoms in the red mud and sediment were sea types. Sea diatoms from McMurdo Sound matched 20.4 percent of the diatom sequence types at Blood Falls, compared with only 1.5 percent of those in other Dry Valleys streams and lakes. Those streams and lakes held mostly freshwater and land diatoms.
研究团队从样本中提取了 RNA，将其转化为互补 DNA，并进行了测序。这显示了南极晚夏采样时生物体的活动情况。基因分析揭示了光合作用、盐胁迫反应和细胞修复。作者表示，这与盐度环境中的生命特征相符，但并不能证明这一点。
The team extracted RNA from the samples, converted it into complementary DNA, and sequenced it. This showed activity of organisms at the time of sampling in late Antarctic summer. Genetic analysis revealed photosynthesis, salt stress response, and cell repair. The authors say this fits with life in a salty setting, though it does not prove it.
另一种可能的解释是风力作用，因为干燥谷风力极大。然而，风力搬运的样本几乎不含海洋信号。作者表示，仅凭当今的风力不太可能解释这种模式。另一类硅藻——毛囊藻，也在血瀑布形成了自己的谱系。其基因类型仅见于该地点。作者推测，该群落很可能由古代海水入侵的长期幸存者、可能的古代风力搬运以及极有限的现代风力输入组成。
Another possible explanation is wind, because the Dry Valleys are very windy. Nevertheless, wind-blown samples contained almost no sea signals. The authors say the wind alone today is unlikely to explain the pattern. Another group of diatoms, Chaetoceros, also created its own lineage at Blood Falls. Its genetic types were unique to that location. The authors suggest that the community is likely composed of long-term survivors from ancient seawater flooding, possible ancient wind transport, and very limited modern wind input.
科学家仍不清楚的问题该研究存在明确局限性。此前的研究在盐水中发现了与海洋细菌关系密切的细菌。但未在盐水本身中检测到具有复杂细胞结构的微小海洋生物，即真核生物。新发现来自冰川末端的红冰、泥浆和沉积物，即盐水与地表接触之处。所用方法也无法确定确切物种。团队也无法观察生物体形态，因为样本太小且保存状况太差。
What scientists still do not knowThe study has definite limitations. Previous work has found bacteria in the brine that are close relatives of sea bacteria. But no tiny sea organisms with complex cells, called eukaryotes, have been detected in the brine itself. The new findings come from the red ice, mud, and sediment at the glacier’s end, where the brine meets the surface. The method used also cannot ascertain exact species. The team also could not check the shapes of the organisms, as the samples were too small and too poorly preserved.
古代风力搬运不能完全排除。关于古代海水到达的范围和时间，问题依然存在。尽管如此，作者将血瀑布描述为古老谱系的独特避难所。他们表示，这为未来研究奠定了基础，未来的工作可能展示残留群落如何记录过去的变化和未来的极地风险。
Ancient wind transport cannot be ruled out entirely. Questions also remain about how far ancient seawater reached and when. Still, the authors describe Blood Falls as a unique refuge for ancient lineages. They say it sets the stage for future work that could show how remnant communities record past change and future polar risk.