Phytoplankton biomass (chlorophyll-a) and community structure in the water column was analyzed across various frontal regions in the Subtropical Front (STF), Sub-Antarctic Front (SAF), Polar Front-1 (PF1) and Polar Front-2 (PF2) in the Indian Ocean sector of the Southern Ocean (SO) during the austral summer (January–February) of 2013 and 2015. The surface chlorophyll-a (Chl-a) was maximum in PF1 (0.77mg m⁻³) followed by the SAF (0.5 mg m⁻³), STF (0.26 mg m⁻³) and PF2 (0.21 mg m⁻³) in 2013. The Chl-a was maximum in the SAF (0.56 mg m⁻³) followed by PF1 (0.32 mg m⁻³), PF2 (0.28 mg m⁻³) and STF (0.20 mg m⁻³) during 2015, indicating that the average surface biomass was higher in 2013. The deep chlorophyll maximum (DCM) was located at 50 m in STF and SAF for 2013 and 2015 and was found at 75 m (100 m) in PF1 (PF2) during 2013. The diagnostic pigment (DP) index indicated that diatoms in the surface and water column increased from the STF to the PF. In contrast, smaller cell community flagellates and prokaryotes decreased from the STF to PF. Diatoms consistently increased from the surface to 120 m in SAF and PF, whereas flagellates were uniformly distributed throughout the water column. Prokaryotes were consistently distributed down to the DCM level and then progressively declined towards deeper regions. The nitrate (NO_3⁻), phosphate (PO₄³⁻) and silicate (SiO₄) increased considerably from the STF to PF through SAF. Results indicate the biomass and community variation in the frontal regions were due to the influence of physical, chemical, and biological processes under varied environmental conditions.

分析了亚热带锋面（STF），南极亚热带锋面（SAF），极地锋1（PF1）和极地锋2（PF2）各个额叶区域的浮游植物生物量（叶绿素a）和群落结构）在2013年和2015年的夏季（1月至2月）的南半球印度洋海域。PF1（0.77mg m ^-3）的表面叶绿素a（Chl-a）最大。2013年，SAF（0.5 mg m ^-3），STF（0.26 mg m ^-3）和PF2（0.21 mg m ^-3）。SAF（0.56 mg m ^-3）中的Chl-a最高，其次是PF1（0.56 mg m ^-3）。 0.32 mg m ^-3），PF2（0.28 mg m^-3）和STF（0.20 mg m ^-3）在2015年期间，表明2013年的平均表面生物量较高。2013和2015年STF和SAF中的深叶绿素最大值（DCM）位于50 m，发现于2013年，PF1（PF2）中75 m（100 m）。诊断色素（DP）指数表明，地表和水柱中的硅藻从STF到PF有所增加。相反，较小的细胞群落鞭毛和原核生物从STF降至PF。在SAF和PF中，硅藻从表面一直增加到120 m，而鞭毛虫则均匀地分布在整个水柱中。原核生物一直分布到DCM水平，然后逐渐向更深的区域下降。硝酸盐（NO _{3 ^-} ），磷酸盐（PO从STF通过SAF到PF，₄ ³⁻）和硅酸盐（SiO ₄）显着增加。结果表明，额叶生物量和群落的变化是由于在各种环境条件下物理，化学和生物过程的影响。