Mesoscale eddies influence the nutrient distribution and modulate the phytoplankton growth. The present study addressed the influence of cyclonic and anticyclonic eddies on the variability of particulate organic matter composition at the Subtropical Front of the Indian Ocean sector of the Southern Ocean during austral summer 2012 and 2013. It was observed that the concentration of particulate organic carbon was lower at the aged cyclonic eddy (29.62 to 59.42 μg/L) compared to that observed at the freshly formed cyclonic eddies (36.03 to 194.19 μg/L). Likewise, at the matured anticyclonic eddies the particulate organic carbon was comparatively lesser (15.10 to 58.94 μg/L) than that noted at the freshly formed eddy (29.54 to 104.44 μg/L). The isotopic signatures of POM (δ¹³C_(POM) & δ¹⁵N_(POM)) were significantly different at the eddy regions. An enrichment of δ¹³C_(POM) was observed at the surface of cyclonic eddies with the highest δ¹³C_(POM) (−21.40‰) at a ~ 3 month old cyclonic eddy. However, an enrichment of δ¹⁵N_(POM) was observed at the depth of deep chlorophyll maxima of anticyclonic eddies with the highest δ¹⁵N_(POM) (4.39‰) at the ~2 month old anticyclonic eddy. The variability in the POM characteristics and the dominant biochemical processes during this study were attributed to the difference in the eddy properties such as age, intensity and its origin. The study also indicated that eddy properties and the associated upwelling and downwelling processes altered the nutrient dynamics and supported a shift in the biological community structure that played a significant role in the variability of POM characteristics at the eddy influenced regions like the Subtropical Front.

中尺度涡流影响养分分布并调节浮游植物生长。本研究探讨了 2012 年和 2013 年南大洋夏季期间气旋和反气旋涡旋对南大洋印度洋亚热带锋区颗粒有机物组成变化的影响。据观察，颗粒有机碳的浓度为与在新形成的气旋涡流（36.03 至 194.19 μg/L）中观察到的相比，在老化的气旋涡流处（29.62 至 59.42 μg/L）较低。同样，在成熟的反气旋涡流中，颗粒有机碳相对较少（15.10 至 58.94 微克/升），比在新形成的涡流中观察到的（29.54 至 104.44 微克/升）相对较少。POM (δ ¹³ C _(POM) & δ¹⁵ N _(POM) ) 在涡流区域显着不同。在气旋涡表面观察到δ ¹³ C _(POM)的富集，在大约 3 个月的气旋涡流中具有最高的 δ ¹³ C _(POM) (-21.40‰)。然而，在具有最高 δ ¹⁵ N _(POM)的反气旋涡旋的深叶绿素最大值的深度处观察到δ ¹⁵ N _(POM)的富集(4.39‰) 在大约 2 个月大的反气旋涡流中。本研究期间 POM 特征和主要生化过程的可变性归因于涡流特性的差异，例如年龄、强度及其起源。该研究还表明，涡流特性和相关的上升流和下降流过程改变了营养动态，并支持了生物群落结构的转变，这种转变在亚热带锋等涡流影响区域的 POM 特征的变化中发挥了重要作用。