River connectivity is often described as a key requirement for maintaining the health and biodiversity of associated wetlands of rivers. A comparative study was undertaken to understand the influence of river connectivity on plankton diversity and abundance in an open (Chharaganga Beel) and a closed wetland (Kalobaur Beel) situated on the banks of River Ganga in West Bengal, India. During the present investigation, data revealed that the major groups of phytoplankton recorded were Cyanobacteria (33.12%), Bacillariophyta (29.07%), and Chlorophyta (22.34%) from the open wetland, and Bacillariophyta (47.40%), Euglenozoa (30.68%), and Chlorophyta (10.12%) from the closed one. Shannon diversity (H') and Margalef's species richness index indicate that phytoplankton diversity in the Chharaganga ecosystem was higher than in Kalobaur Beel. A one-way ANOVA showed significant station-wise difference for water turbidity (p<0.05) in both of the beels, and student t test revealed that differences in physico-chemical parameters between the studied beels was statistically significant (p<0.05) for depth, turbidity, conductivity, total hardness, nitrate, total N, phosphate-P, silicate, Ca2+, Mg2+and chlorophyll a,whereas abundance of phytoplankton groups was significantly different for Bacillariophyta (p<0.05) and Euglenozoa (p<0.05). The positive correlation of total N with Euglenozoa (r=0.496; p<0.05) might be the cause of favourable conditions for a higher abundance of Euglenozoa in the closed Kalobaur Beel,which is on the verge of partial eutrophication. The hydrological flushing by river water in the Chharaganga wetland maintains the ecological stability. Therefore, restoration of river connectivity is recommended to improve the health of the disconnected wetlands.

中文翻译：

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河流连通性对恒河相关湿地浮游植物丰度和多样性的影响：开放和封闭湿地的比较研究

河流连通性通常被描述为维持河流相关湿地的健康和生物多样性的关键要求。进行了一项比较研究，以了解河流连通性对位于印度西孟加拉邦恒河沿岸的开放湿地（Chharaganga Beel）和封闭湿地（Kalobaur Beel）的浮游生物多样性和丰度的影响。在本次调查中，数据显示，记录的主要浮游植物群是开阔湿地的蓝藻门（33.12%）、芽孢杆菌门（29.07%）和绿藻门（22.34%），以及芽孢杆菌门（47.40%）、裸藻门（30.68%） ，和绿藻（10.12%）来自封闭的一种。Shannon 多样性 (H') 和 Margalef 的物种丰富度指数表明，Chharaganga 生态系统中的浮游植物多样性高于 Kalobaur Beel。单向 ANOVA 显示两种蜂的水浊度有显着的站位差异 (p<0.05)，学生 t 检验显示所研究的蜂之间的物理化学参数差异具有统计学意义 (p<0.05)深度、浊度、电导率、总硬度、硝酸盐、总 N、磷酸盐-P、硅酸盐、Ca2+、Mg2+ 和叶绿素 a，而浮游植物群的丰度在芽孢杆菌门 (p<0.05) 和眼虫纲 (p<0.05) 中存在显着差异. 总氮与眼虫的正相关（r=0.496；p<0.05）可能是处于部分富营养化边缘的封闭的Kalobaur Beel中眼虫的丰度较高的有利条件。恰拉甘加湿地的河水水文冲刷维持了生态稳定。所以，