This study aims to estimate, with a climatology perspective, the average seasonal pattern of phytoplankton biomass (SP-PBavg) and its distribution in Bahia Magdalena (Mexico) as a baseline to evaluate PB changes in future studies. This lagoon is in a semi-arid region, lacks river discharges, and channels with vegetation are limited at the north and south zones. SP-PBavg was estimated with chlorophyll-a (chl-a) data obtained in 21 sites on daily MODIS-Aqua imagery (2002–2013; n = 2,418) from a ready-to-use public database. The first step was to establish criteria to use imagery and validate with in situ observations taken in 14 sites (2002–2011; n = 312). MODIS-Aqua overestimated chl-a (mean ± confidence interval₉₅: 5.09 ± 0.97 mg m⁻³; n = 225); with differences among sites. There were no differences near the inlet lagoon (p <0.05), where the water characteristics are Case-1 while values were significantly higher in the eastern shore and two or three times higher in the mouth of north and south channels, whose water characteristics are similar to Case-2. Multivariate statistical methods allow defining zones into the lagoon and describe their SP-PBavg with both in situ and MODIS Aqua data, but the former's sample size was small, and the patterns were only delineated. In the inlet surroundings, chl-a peaks from March/April to June/July. On the eastern shore, where MODIS Aqua and in situ data were correlated, despite concentration differences, chl-a is higher from March/April to October, with peaks in June and September. In the mouth of internal channels, chl-a was higher than other sites and during a longer period; however, the very high MODIS-Aqua values suggest that the satellite also detects organic matter supplied by phytoplankton and other vegetables, which explain the high lagoon's productivity. These results validate the use of MODIS Aqua imagery to describe the chl-a seasonal patterns in the sea's vicinity.

本研究旨在从气候学角度估计浮游植物生物量的平均季节性模式 (SP-PBavg) 及其在巴伊亚马格达莱纳（墨西哥）的分布，作为评估未来研究中 PB 变化的基线。该泻湖位于半干旱地区，缺乏河流排放，北部和南部带植被的渠道有限。SP-PBavg用叶绿素估计一个（chl-一个从一个准备使用的公共数据库中;在上每日MODIS-水族图像21个站点获得）数据（N = 2418 2002年至2013年）。第一步是建立使用图像的标准，并通过在 14 个地点（2002-2011 年；n = 312）进行的原位观察进行验证。MODIS-Aqua 高估了 chl- a（平均值 ± 置信区间₉₅： 5.09 ± 0.97 毫克 m ^-3；n = 225); 与站点之间的差异。泻湖入口附近无差异（p <0.05），水特征为Case-1，东岸明显偏高，南北水道口高2-3倍，水特征为Case-1类似于案例2。多变量统计方法允许将区域定义为泻湖并使用原位和 MODIS Aqua 数据描述其 SP-PBavg ，但前者的样本量很小，并且仅描绘了模式。在入口周围，chl- a在 3/4月至6/7月达到高峰。在东岸，MODIS Aqua 和原位数据是相关的，尽管浓度存在差异，但3 月/4 月至 10 月chl- a较高，6 月和 9 月达到峰值。内经口chl- a高于其他部位，时间较长；然而，非常高的 MODIS-Aqua 值表明卫星还探测到浮游植物和其他蔬菜提供的有机物质，这解释了泻湖的高生产力。这些结果验证了使用 MODIS Aqua 图像来描述海洋附近的 chl- a季节性模式。