Quantifying phytoplankton and its changes in coastal waters is an important aspect of marine ecosystems. Synoptic observations of phytoplankton communities became possible with remote sensing technologies and spatial analysis methods. Using these advancements would assist the scientific community to gain better understanding of marine ecosystem dynamics and consequently contribute in sustaining and maintaining these valuable ecosystems. Thus, this study aimed to evaluate the water quality and aquatic ecosystem status of Algiers Bay, Algeria, through the quantification of diatoms and dinoflagellates species using in-situ measurements and Landsat images. We developed empirical models to assess phytoplankton abundance by comparing in-situ measurements of diatoms and dinoflagellates with various spectral bands and band ratioing products derived from Landsat-8 OLI images acquired in 4 April 2017 and 9 May 2018. The results showed a wide variation between coastal and offshore stations. The number of diatoms was less than that of dinoflagellates. These two algae communities illustrated a different spectral behavior. Diatoms showed a significant relationship with one of the ratioing products (i.e., log B7/log B2), whereas dinoflagellates exhibited an insignificant relationship with the remotely sensed dataset. Also, we learned that the southeastern area of the bay can be influenced by harmful algae blooms developed offshore because of hydrodynamic forces that push these blooms toward this area of the bay.

量化近海浮游植物及其变化是海洋生态系统的重要方面。利用遥感技术和空间分析方法，对浮游植物群落进行天气观测成为可能。利用这些进步将有助于科学界更好地了解海洋生态系统动态，从而有助于维持和维护这些宝贵的生态系统。因此，本研究旨在通过使用原位测量和Landsat影像对硅藻和鞭毛藻物种进行量化来评估阿尔及利亚阿尔及尔湾的水质和水生生态系统状况。我们开发了经验模型，通过比较硅藻和硅藻鞭毛的原位测量值与从2017年4月4日和2018年5月9日获得的Landsat-8 OLI图像衍生的各种光谱带和谱带配比产品，来评估浮游植物的丰度。结果表明，沿海和近海站。硅藻的数量少于鞭毛藻的数量。这两个藻类群落说明了不同的光谱行为。硅藻显示出与一种定量产物（即log B7 / log B2）之间的显着关系，而硅藻鞭毛虫与遥感数据集之间的关系不明显。也，