Lake Morenito located in the Argentinean Patagonia has been exposed to climatic, volcanic, and anthropogenic impacts for the last decades. In particular, the damming of the lake and the eruption of the Calbuco/Puyehue Volcanoes in AD 1960 played an important role in the lake’s history. A 80-cm-long sediment core from Lake Morenito spanning more than 100 years was studied for chironomids, stable isotopes, and organic geochemistry to investigate how natural and anthropogenic stressors impacted the lake. Chironomid assemblages display large changes around AD 1950, with the appearance of the warm-adapted Chironomus and the replacement of Apsectrotanypus by Ablabesmyia , indicating a shift to warmer conditions. By that time and up to the present, an increasing trend of δ 15 N coupled with a decrease of δ 13 C points to shifts in the carbon and nitrogen cycles associated with human activities. It is evident that the onset of human activities during the 1950s following by the lake damming in AD 1960 had significant effects on the chironomid assemblages and the geochemical composition of sediments which is reflected in the progressive deterioration of the lake ecosystem.

中文翻译：

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人类活动和气候对阿根廷北部巴塔哥尼亚莫雷尼托湖的影响

在过去的几十年里，位于阿根廷巴塔哥尼亚的莫雷尼托湖一直受到气候、火山和人为影响。特别是，公元 1960 年，该湖的筑坝和 Calbuco/Puyehue 火山的喷发在该湖的历史中发挥了重要作用。研究了来自莫里尼托湖 100 多年的 80 厘米长沉积岩心的摇蚊、稳定同位素和有机地球化学，以研究自然和人为压力因素如何影响湖泊。摇蚊组合在公元 1950 年左右显示出巨大的变化，随着适应温暖的摇蚊的出现和 Ablabesmyia 取代了 Apsectrotanypus，表明向温暖条件的转变。那个时候到现在，δ 15 N 的增加趋势加上 δ 13 C 的减少表明与人类活动相关的碳和氮循环发生了变化。很明显，公元 1960 年湖泊筑坝后 1950 年代开始的人类活动对摇蚊群和沉积物的地球化学组成产生了显着影响，这反映在湖泊生态系统的逐渐恶化中。