Chlorophyll-a (Chl-a) and Total Suspended Matter (TSM) are key health indicators of the coastal ocean and seas. The former is linked to primary productivity, while the latter is associated with water quality; both are influenced by change in climate. Recent studies have highlighted a declining trend in Chl-a levels along the Mediterranean coastal region. River discharge plays an important role in regulating the coastal Chl-a concentration levels. The present research primarily focuses on understanding the significance of Tiber River −driven spatial dynamics of Chl-a and TSM along the central Tyrrhenian Sea coasts. The research also focuses on evaluating the applicability of Sentinel-2 and identifying a suitable method for estimating Chl-a and TSM from Sentinel-2. Neural networks and dark spectrum fitting techniques were applied using multiple algorithms to estimate the dynamic distribution of Chl-a and TSM driven by the Tiber River in the study area. Multiple statistical analyses were performed, and statistically significant relationships were observed. The Case-2 Regional Coast Colour Neural Network (C2RCC-Net) outperformed all other algorithms, with an R value of 0.903 for Chl-a and an R value of 0.966 for TSM. Furthermore, the present research also identified a positive pixel to pixel spatial correlation between Chl-a and TSM in all four seasons, highlighting the positive impact of Tiber River on maintaining Chl-a levels along the coasts of Tyrrhenian Sea. This stands in contrast with the negative trend seen in the Mediterranean scale.

中文翻译：

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台伯河驱动的叶绿素-a 和总悬浮物动态及其对第勒尼安海中部沿岸的影响：Sentinel-2 方法


叶绿素-a (Chl-a) 和总悬浮物 (TSM) 是沿海海洋的关键健康指标。前者与初级生产力有关，后者与水质有关；两者都受到气候变化的影响。最近的研究强调了地中海沿岸地区叶绿素a水平下降的趋势。河流流量对调节沿海叶绿素a浓度水平起着重要作用。目前的研究主要集中于了解台伯河驱动的第勒尼安海中部沿岸叶绿素a和TSM空间动态的重要性。该研究还侧重于评估 Sentinel-2 的适用性，并确定从 Sentinel-2 估算 Chl-a 和 TSM 的合适方法。采用多种算法应用神经网络和暗光谱拟合技术来估计研究区受台伯河驱动的叶绿素a和TSM的动态分布。进行了多项统计分析，并观察到统计上显着的关系。 Case-2 区域海岸颜色神经网络 (C2RCC-Net) 的性能优于所有其他算法，Chl-a 的 R 值为 0.903，TSM 的 R 值为 0.966。此外，本研究还确定了所有四个季节叶绿素 a 和 TSM 之间的正像素到像素空间相关性，突出了台伯河对维持第勒尼安海沿岸叶绿素 a 水平的积极影响。这与地中海规模的负面趋势形成鲜明对比。