Abstract Enhanced nutrient input and warming have led to the development of low oxygen (hypoxia) in coastal waters globally. For many coastal areas, insight into redox conditions prior to human impact is lacking. Here, we reconstructed bottom water redox conditions and sea surface temperatures (SSTs) for the coastal Stockholm Archipelago over the past 3000 yr. Elevated sedimentary concentrations of molybdenum indicate (seasonal) hypoxia between 1000 b.c.e. and 1500 c.e. Biomarker‐based (TEX86) SST reconstructions indicate that the recovery from hypoxia after 1500 c.e. coincided with a period of significant cooling (∼ 2°C), while human activity in the study area, deduced from trends in sedimentary lead and existing paleobotanical and archeological records, had significantly increased. A strong increase in sedimentary lead and zinc, related to more intense human activity in the 18th and 19th century, and the onset of modern warming precede the return of hypoxia in the Stockholm Archipelago. We conclude that climatic cooling played an important role in the recovery from natural hypoxia after 1500 c.e., but that eutrophication and warming, related to modern human activity, led to the return of hypoxia in the 20th century. Our findings imply that ongoing global warming may exacerbate hypoxia in the coastal zone of the Baltic Sea.

中文翻译：

---

从现代人类活动终止的波罗的海斯德哥尔摩群岛的千年自然沿海缺氧中恢复

摘要 养分输入增加和气候变暖导致全球沿海水域出现低氧（缺氧）现象。对于许多沿海地区，缺乏对人类影响之前氧化还原条件的了解。在这里，我们重建了过去 3000 年斯德哥尔摩群岛沿海的底水氧化还原条件和海面温度 (SST)。钼的沉积浓度升高表明 1000 bce 和 1500 ce 之间的（季节性）缺氧 基于生物标志物 (TEX86) 的 SST 重建表明 1500 ce 后从缺氧中恢复恰逢显着冷却时期 (~ 2°C)，而人类活动在研究区，根据沉积铅趋势和现有古植物和考古记录推断，显着增加。沉积铅锌大幅增加，与 18 和 19 世纪更强烈的人类活动有关，并且现代变暖的开始先于斯德哥尔摩群岛缺氧的回归。我们得出结论，气候变冷在 1500 ce 后自然缺氧的恢复中发挥了重要作用，但与现代人类活动相关的富营养化和变暖导致了 20 世纪缺氧的回归。我们的研究结果表明，持续的全球变暖可能会加剧波罗的海沿岸地区的缺氧。导致了20世纪缺氧的回归。我们的研究结果表明，持续的全球变暖可能会加剧波罗的海沿岸地区的缺氧。导致了20世纪缺氧的回归。我们的研究结果表明，持续的全球变暖可能会加剧波罗的海沿岸地区的缺氧。