A multi-proxy analysis, including pollen, non-pollen palynomorphs and plant macrofossil remains was performed to reconstruct the paleoenvironmental history of the Cabeza de Buey shallow lake (36°17′S, 61°10′W) over the last 600 years. We identified the main forcing factors behind changes in the structure and dynamics of the lake communities. Given the relatively low intensity of human activity during the early period of the lake history (prior to 1880 AD), changes in dominant communities were mainly controlled by climate. Afterwards, changes probably resulted from a combination of climate and human impacts that generated an accelerated eutrophication. Four periods in the lake’s evolution were recognized based on changes in macrophyte and algae communities’ structure. Between ca. 1320 and ca. 1630 AD a shift was evidenced from an oligotrophic brackish with low nutrient content (dominated by Botryococcus braunii) to a mesotrophic fresh water body (dominated by Pediastrum and Scenedesmus), due to an increase in the water level associated with an increase in precipitation. At ca. 1840 AD a transition towards a phase dominated by Myriophyllum spicatum was noted, induced by a low water level as a consequence of low precipitation. Later, at ca. 1880 AD, the current lake conditions were established, and the increase in nutrient and organic matter supply influenced plant community structure towards organic tolerant species of submerged macrophytes (Potamogeton pectinatus). Towards the beginning of the twenty-first century, the lake turned to a more eutrophic state, which is evidenced by the dominance of the phytoplankton community. The last hundred years of the lake history were characterized by the eutrophication process related to the impact of agriculture and cattle breeding implemented in the landscape as well as to the urban settlement. This study made it possible to infer changes in the structure and dynamics of Cabeza de Buey lake and to elucidate the forcing factors that induced these changes on a high-resolution scale.

进行了包括花粉，非花粉类植物形态和植物化石残留物在内的多代理分析，以重建过去600年Cabuza de Buey浅湖（36°17′S，61°10′W）的古环境历史。我们确定了湖泊群落结构和动态变化背后的主要强迫因素。考虑到湖泊历史早期（公元1880年之前）人类活动的强度相对较低，优势社区的变化主要由气候控制。之后，气候变化和人类影响共同导致富营养化加速，可能导致变化。根据大型植物和藻类群落结构的变化，可以识别出湖泊演化的四个时期。介于ca之间。1320和ca。公元1630年，由于水位的增加与降水量的增加有关，营养成分低的寡营养型微咸水（以Botryococcus braunii为主）转变为中营养型淡水水体（以Pediastrum和Scenedesmus为主）。在加利福尼亚州。公元1840年，由于低降水导致的水位低，引起了向斑鸠鼠（Myriophyllum spicatum）占主导地位的阶段的转变。后来，在加利福尼亚州。公元1880年，当前的湖泊条件得以确立，养分和有机质供应的增加影响了淹没大型植物对有机耐受物种的植物群落结构（Potamogeton pectinatus）。在二十一世纪初，湖泊变成了一种富营养化的状态，浮游植物群落的主导地位证明了这一点。湖泊历史的最后一百年以富营养化过程为特征，该富营养化过程与景观中实施的农业和牲畜育种的影响以及城市定居有关。这项研究有可能推断出Cabeza de Buey湖的结构和动力学变化，并阐明了导致高分辨率变化的强迫因素。