Chlorophyll-a (Chl-a) is an optically active compound commonly used as a proxy for phytoplankton biomass and trophic state in an aquatic system. This work aimed to analyze the spatiotemporal variation of Chl-a values in six Araucanian lakes in Central-South Chile. Here we combined in-situ Chl-a measurements and thirteen Landsat 8 satellite images to build a set of the linear and non-linear models to estimate Chl-a values in the lakes. Through the Taylor diagram, r Pearson, standard deviation, and other statistical indicators (R2, RMSE, IA, and MBE) the Chl-a models were validated. A qualitative/quantitative analysis to identify the species of microalgae present in the lacustrine systems was used. Next, Chl-a estimation maps were created to understand the spatial and seasonal behavior of this variable in each aquatic ecosystem. We observed that during the Summer months the Chl-a values are higher than in the Spring months for all lakes, except in Pirehueico lake. Moreover, the Chl-a models created predict with high accuracy, the results of statistical indicators are R2 ≥ 0.94, IA ≥ 0.80, RMSE ≤0.214 μg/L, and MBE ≤ −0.123 μg/L. In the lake systems were found two invasive species, C. hirundinella, and Didymosphenia geminata, species recognized as bloom-forming in other aquatic systems. Finally, the Chl-a maps provided information on the monitoring of areas sensitive to Chl-a changes. This study is very important to conserve the water quality and early alert to forming phenomena like algal blooms which contributes to providing useful data for managers and policy-makers in Chilean lakes.

叶绿素-a (Chl-a) 是一种光学活性化合物，通常用作水生系统中浮游植物生物量和营养状态的代表。这项工作旨在分析智利中南部六个阿劳卡尼亚湖泊中 Chl-a 值的时空变化。在这里，我们结合了原位 Chl-a 测量值和十三个 Landsat 8 卫星图像来构建一组线性和非线性模型来估计湖泊中的 Chl-a 值。通过泰勒图、r Pearson、标准偏差和其他统计指标（R2、RMSE、IA 和 MBE）验证了 Chl-a 模型。使用定性/定量分析来确定湖泊系统中存在的微藻种类。接下来，创建 Chl-a 估计图以了解该变量在每个水生生态系统中的空间和季节性行为。我们观察到，除了 Pirehueico 湖之外，所有湖泊在夏季月份的 Chl-a 值都高于春季月份。此外，所创建的 Chl-a 模型预测精度高，统计指标结果为 R2 ≥ 0.94、IA ≥ 0.80、RMSE ≤0.214 μg/L、MBE ≤ -0.123 μg/L。在湖泊系统中发现了两种入侵物种，C. hirundinella和Didymosphenia geminata，在其他水生系统中被认为是形成水华的物种。最后，Chl-a 地图提供了有关监测对 Chl-a 变化敏感的区域的信息。这项研究对于保护水质和早期预警藻华等现象的形成非常重要，这有助于为智利湖泊的管理者和决策者提供有用的数据。