Abstract：
The COVID-19 pandemic\'s disruptions to human activities prompted serious environmental changes. Here, we assessed the variations in coastal water quality along the Caspian Sea, with a focus on the Iranian coastline, during the lockdown. Utilizing Chlorophyll-a data from MODIS-AQUA satellite from 2015 to 2023 and Singular Spectrum Analysis for temporal trends, we found a 22% Chlorophyll-a concentration decrease along the coast, from 3.2 to 2.5 mg/m³. Additionally, using a deep learning algorithm known as Long Short-Term Memory Networks, we found that, in the absence of lockdown, the Chlorophyll-a concentration would have been 20% higher during the 2020-2023 period. Furthermore, our spatial analysis revealed that 98% of areas experienced about 18% Chlorophyll-a decline. The identified improvement in coastal water quality presents significant opportunities for policymakers to enact regulations and make local administrative decisions aimed at curbing coastal water pollution, particularly in areas experiencing considerable anthropogenic stress.
摘要：
COVID-19大流行对人类活动的破坏引发了严重的环境变化。这里,我们评估了里海沿岸水质的变化，关注伊朗海岸线，在封锁期间。利用2015年至2023年MODIS-AQUA卫星的叶绿素a数据和奇异频谱分析的时间趋势，我们发现沿海的叶绿素a浓度下降了22%,从3.2到2.5毫克/立方米。此外,使用称为长短期记忆网络的深度学习算法，我们发现,在没有封锁的情况下,在2020-2023年期间，叶绿素a浓度将高出20%。此外，我们的空间分析表明，98%的地区经历了约18%的叶绿素a下降。沿海水质的改善为决策者制定法规和做出旨在遏制沿海水污染的地方行政决定提供了重要机会，特别是在经历相当大的人为压力的地区。
