We present results from Lago Negro, a small closed-basin lake adjacent to Lago Rosselot, to examine the vegetation and environmental history of an insufficiently studied sector of Chiloé Continental (41°30′-44°S) in northwestern Patagonia. Lake sediment cores from Lago Negro reveal 27 tephra deposited since ∼12.7 ka, including two prominent rhyodacite tephra marker beds erupted from Volcán Melimoyu, and a stratified basal clastic unit we attribute to meltwater discharge from an ice tongue that originated from Monte Queulat and covered Lago Rosselot during its expanded position, presumably Antarctic Cold Reversal in age. The pollen record shows closed-canopy North Patagonian rainforests since ∼12.7 ka, with variations in species composition and structure that suggest dynamic responses of the vegetation to past environmental changes. Vegetation responses to climate in the Lago Negro record were modulated, sometimes interrupted, by high magnitude and frequent disturbance regimes, most notably during maxima in explosive volcanic activity (∼9.5–7.2 ka and ∼3.6–1.6 ka) and heightened fire activity.

Since Lago Negro is the southernmost palynological site so far investigated in the region and is located within a volcanically active sector, it provides a valuable perspective for assessing past vegetation responses along environmental gradients since the last glaciation. When compared with other sites throughout northwestern Patagonia, our record reveals a distinct north-to-south gradient in temperature and precipitation, with peak temperature and rainfall seasonality in the north, and a west-to-east gradient in disturbance regimes, with maximum frequency and magnitude of explosive volcanic events in the east. These gradients have modulated the response of rainforest vegetation to climate forcing at regional scale since ∼12.7 ka. We identify negligible differences in timing for the majority of key vegetation signals during the initial phase of the Lago Negro record, and propose that plant colonization and expansion along the ∼360 km long corridor through the Pacific slope of the northwestern Patagonian Andes was a rapid process during the Last Glacial Termination.

我们提出了Lago Negro（毗邻Lago Rosselot的小型封闭盆地湖）的结果，以研究西北巴塔哥尼亚ChiloéContinental（41°30′-44°S）未充分研究的部分的植被和环境历史。Lago Negro的湖泊沉积物岩心揭示了自12.7 ka以来沉积的27 tephra，包括从VolcánMelimoyu喷发的两个突出的流纹岩Tephra标记床，以及一个分层的基底碎屑单元，我们将其归因于源自Monte Queulat和覆盖Lago的冰舌融化的融水排放。罗塞洛特（Rosselot）处于扩张期，大概是年龄上的南极逆转。花粉记录显示了约12.7 ka以来的北巴塔哥尼亚封闭林冠雨林，物种组成和结构的变化表明植被对过去环境变化的动态响应。

由于拉各·内格罗（Lago Negro）是该地区迄今调查的最南端的孢粉学地点，并且位于火山活动区，因此它为评估自上次冰川以来沿环境梯度的过去植被反应提供了宝贵的前景。与整个巴塔哥尼亚西北部的其他地点相比，我们的记录揭示了温度和降水的明显的北-南梯度变化，北部为峰值温度和降雨季节，扰动范围为西-东梯度变化，频率最高和东部爆炸性火山事件的规模。自大约12.7 ka以来，这些梯度在区域尺度上调节了雨林植被对气候强迫的响应。