The Mar Menor hypersaline coastal lagoon has suffered serious degradation in the last three decades attributable to nutrient pollution. In 2015, the lagoon experienced an intensive bloom of cyanobacteria that triggered a drastic change of its ecosystem. Our analyses indicate that phytoplankton in 2016–2021 did not present a seasonal variability pattern; the community was mainly dominated by diatoms and punctually reached abundance peaks above 10⁷ cell L⁻¹ along with chlorophyll a concentrations exceeding 20 μg L⁻¹. The predominant diatom genera during these blooms were different as well as the nutrient conditions under which they were produced. These high diatom abundances are unprecedented in the lagoon; in fact, our data indicate that the taxonomic composition, time variation patterns and cell abundance of phytoplankton in 2016–2021 differ notably in comparison to the data published before 2015. Consequently, our results support the finding that the trophic status of the lagoon has changed profoundly.

Mar Menor 高盐度沿海泻湖在过去 30 年中因营养物污染而严重退化。2015 年，泻湖经历了蓝藻的密集繁殖，引发了生态系统的剧烈变化。我们的分析表明，2016-2021 年的浮游植物没有呈现季节性变化模式；该群落主要以硅藻为主，准时达到 10 ⁷细胞 L ⁻¹以上的丰度峰值以及超过 20 μg L ^{−1的叶绿素}a浓度. 这些大量繁殖期间的主要硅藻属以及它们产生的营养条件不同。这些高硅藻丰度在泻湖中是前所未有的；事实上，我们的数据表明，与 2015 年之前发布的数据相比，2016-2021 年浮游植物的分类组成、时间变化模式和细胞丰度有显着差异。因此，我们的结果支持泻湖营养状况发生变化的发现深刻地。