This present study was conducted to extend our understanding on the relationship between Chlorophyll a (Chl a) concentration and hydrological parameters typically flow velocity, environmental variables and trophic state conditions using lotic water as experimental system. River Mahanadi, India was selected as a model for the present study. Based on elevation from mean sea level, twelve sampling sites from Sambalpur to Naraj were grouped into three zones viz. upper zone (71 km), middle zone (142 km) and lower zone (103 km). Carlson Trophic State Index (CTSI) revealed eutrophic state in middle and lower zone and with mesotrophic condition in the upper zone. Along the river stretch, a negative correlation was observed between Chl a concentration and flow velocity at all three zones during post monsoon (r = − 0.15) and monsoon (r = − 0.31). Seasonal study revealed higher Chl a concentration (16.16–283.85 µg l⁻¹) in post-monsoon with recorded mean flow velocity (0.28 ± 0.19 ms⁻¹) as compared to monsoon season with lower Chl a (18.68–232.24 µg l⁻¹) and mean flow velocity (0.54 ± 0.21 ms⁻¹). Among environmental variables, water temperature and pH showed a positive correlation with Chl a. Overall, the findings of this study illustrated the occurrence of higher phytoplankton biomass (quantified as Chl a) during post-monsoon season coincides with low water velocity. The dataset of this work can be implicated for the hydrological and the ecological framework of the tropical river Mahanadi in the Indian Territory.

中文翻译：

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浮游植物生物量与流量动态的关系：以印度马哈纳迪河为例

进行本研究是为了扩展我们对使用叶绿素水作为实验系统的叶绿素a（Chl a）浓度与水文参数（通常为流速，环境变量和营养状态）之间关系的理解。本研究选择印度河马哈纳迪河作为模型。根据平均海平面的高程，从桑巴尔普尔到纳拉杰的十二个采样点被分为三个区域。上层（71公里），中层（142公里）和下层（103公里）。卡尔森营养状态指数（CTSI）显示中部和下部区域为富营养状态，上部区域为中营养状态。沿河拉伸，叶绿素之间观察到的负相关性一季风后（r = − 0.15）和季风（r = − 0.31）期间所有三个区域的浓度和流速。季节性研究揭示更高叶绿素一个浓度（16.16-283.85微克升^-1在后季风）与记录平均流速（0.28±0.19毫秒^-1相比，雨季具有较低叶绿素）一个（18.68-232.24微克升^-1）和平均流速（0.54±0.21 ms ^-1）。间环境变量，水的温度和pH显示出与叶绿素a的正相关一个。总体而言，本研究的结果示出的较高的浮游植物生物量的发生（量化为叶绿素一个）在季风后季节与低水速相吻合。这项工作的数据集可能与印度领土热带河流Mahanadi的水文和生态框架有关。