Comparison of phytoplankton community structure in two tropical estuaries of East Coast of India

Current Botany ◽

10.25081/cb.2020.v11.6382 ◽

2020 ◽

pp. 159-170

Author(s):

Chumki Chowdhury

Keyword(s):

Phytoplankton Community ◽

East Coast ◽

Inorganic Nitrogen ◽

Community Change ◽

Estuarine Water ◽

East Coast Of India ◽

Estuarine Waters ◽

Dissolved Phosphorus ◽

Dissolved Nitrogen ◽

Dissolved Silicate

Phytoplankton community of two tropical river estuaries of the North-east coast of India was different due to dissolved nutrients concentration in those estuarine waters. The first study site was the Saptamukhi river estuary which is located in the Indian Sundarban (inside mangrove forest) and the second study site was Mahanadi estuary located in Orissa coast (adjacent to industrial and coastal fishing zone). The Saptamukhi estuary was mostly devoid of any anthropogenic influence and here the nutrient source was auto-generated. In Mahanadi estuarine water, the source of the major nutrients was industrial effluent and fishing waste. The Saptamukhi estuarine water had less dissolved phosphorus concentration but huge dissolved nitrogen available for phytoplankton uptake. A sufficient amount of dissolved silicate encouraged the diatom growth over other phytoplankton groups here. Due to the availability of the high amount of dissolved phosphorus and the low amount of dissolved nitrogen in the Mahanadi estuary the phytoplankton community was a mixed population of Bacillariophyceae, Cyanophyceae, Chlorophyceae and Dinophyceae and seasonal Chlorophycean bloom observed during the study period. In both the estuarine water primary productivity was high but the community respiration was higher and the estuaries were heterotrophic. Monsoonal runoff from land considerably changed the community in both estuarine water. Dissolved silicate concentration in both the estuarine water was sufficient for Diatom growth. Dissolve inorganic nitrogen and dissolved inorganic phosphate ratio played a major role for the community change of phytoplankton in two estuarine waters.

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Investigation of nitrogen and phosphorus contents in water in the tributaries of Danjiangkou Reservoir

Royal Society Open Science ◽

10.1098/rsos.170624 ◽

2018 ◽

Vol 5 (1) ◽

pp. 170624 ◽

Cited By ~ 4

Author(s):

Yan Liu ◽

Yuanyuan Zhu ◽

Xiaocui Qiao ◽

Binghui Zheng ◽

Sheng Chang ◽

...

Keyword(s):

Inorganic Nitrogen ◽

Organic Pollution ◽

Test Results ◽

Nitrogen And Phosphorus ◽

Danjiangkou Reservoir ◽

Dissolved Phosphorus ◽

Dissolved Nitrogen ◽

Quality Water ◽

The Government ◽

Surface Water Samples

As part of the efforts to ensure adequate supply of quality water from Danjiangkou Reservoir to Beijing, surface water samples were taken from the tributaries of Danjiangkou Reservoir in the normal (May), flood (August) and dry (December) seasons of 2014, and characterized for nitrogen and phosphorus contents as specified in the applicable standards. Test results indicated that (i) the organic pollution in the Sihe and Shendinghe rivers was more serious than those in other tributaries, and the concentrations of nitrogen and phosphorus favoured the growth of most algae; (ii) total phosphorus (TP), total nitrogen (TN) and dissolved inorganic nitrogen (DIN) were in the forms of dissolved phosphorus (DTP), dissolved nitrogen (DTN) and nitrate nitrogen ( NO 3 − -N ) , respectively, in these seasons; (iii) compared with nitrogen, phosphorus was more likely to block an overrun of phytoplankton; (iv) TN, TP, permanganate index (COD Mn ) and other ions were positively correlated. These findings are helpful for the government to develop effective measures to protect the source water in Danjingkou Reservoir from pollution.

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Responses of Free-Living Vibrio Community to Seasonal Environmental Variation in a Subtropical Inland Bay

Frontiers in Microbiology ◽

10.3389/fmicb.2020.610974 ◽

2020 ◽

Vol 11 ◽

Author(s):

Xing Chen ◽

Huaxian Zhao ◽

Gonglingxia Jiang ◽

Jinli Tang ◽

Qiangsheng Xu ◽

...

Keyword(s):

Inorganic Nitrogen ◽

Environmental Variation ◽

Mantel Test ◽

Beibu Gulf ◽

Test Analysis ◽

Dissolved Phosphorus ◽

Dissolved Nitrogen ◽

Β Diversity ◽

Total Dissolved Nitrogen ◽

Filtering Effect

Vibrio are widely distributed in aquatic environments and strongly associated with eutrophic environments and human health through the consumption of contaminated seafood. However, the response of the Vibrio community to seasonal variation in eutrophic environments is poorly understood. In this study, we used a Vibrio-specific 16S rRNA sequencing approach to reveal the seasonal distribution pattern and diversity of the Vibrio community in the Maowei Sea, Beibu Gulf of China. The Shannon diversity of the Vibrio community was highest in the summer, while β-diversity analysis showed that Vibrio community structures were significantly different between seasons. Distance-based redundancy analysis (dbRDA) and Mantel test analysis suggested that total dissolved nitrogen (TDN), total dissolved phosphorus (TDP), dissolved inorganic nitrogen (DIN), salinity, and temperature were the key environmental factors shaping the Vibrio community structure, indicating a strong filtering effect of trophic condition on Vibrio communities. Furthermore, through random forest analysis, V. fluvialis, V. alginolyticus, V. proteolyticus, V. splendidus, and the other eight Vibrio species were more sensitive to eutrophic changes. This study revealed seasonal changes in Vibrio communities and the influence of environmental variation on Vibrio community composition, contributing to a better understanding of their potential ecological roles in a subtropical inland bay.

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Composition and Dynamics of Phytoplankton in the Coastal Bays of Maryland, USA, Revealed by Microscopic Counts and Diagnostic Pigments Analyses

Water ◽

10.3390/w11020368 ◽

2019 ◽

Vol 11 (2) ◽

pp. 368 ◽

Cited By ~ 3

Author(s):

Ozuem Oseji ◽

Chunlei Fan ◽

Paulinus Chigbu

Keyword(s):

Phytoplankton Community ◽

Anthropogenic Impacts ◽

Dissolved Phosphorus ◽

Coastal Bays ◽

Toxic Species ◽

Dissolved Nitrogen ◽

The Past ◽

Total Dissolved Nitrogen ◽

Maryland Coastal Bays ◽

First Time

Maryland Coastal Bays (MCBs) have undergone changes in water quality in the past two decades due to nutrient enrichment but the composition and dynamics of the phytoplankton community have not been adequately described. Microscopic counts and photosynthetic pigments of samples collected monthly in 2012 at selected sites in MCBs that differed with regard to the degree of anthropogenic impacts were examined. Sixty-three (63) phytoplankton genera were recorded, of which 40 species are being reported for the first time in the Bays. Among the dominant species were Dactyliosolen fragilissimus (Bacillariophyta), Paulinella ovalis (Cercozoa) and Cryptomonas sp. (Cryptophyta). Bloom densities of Heterocapsa rotundata (Miozoa), which previously had not been reported in the Bays, were observed bay-wide in December, particularly at the mouth of St. Martin River. Diatoms dominated (>40%) the phytoplankton community in winter and decreased in spring (<40%), while Cercozoa and microphytoflagellates (MPF) co-dominated in summer (July). From August to October, diatoms dominated with maximum contributions from an unidentified small (<10 µM) centric species and co-dominated the assemblage with cryptophytes in late fall (November). Canonical correspondence analysis indicated that diatoms were favored by high salinity and total dissolved phosphorus (TDP), cercozoans and chlorophytes by total dissolved nitrogen (TDN) and cryptophytes by dissolved organic carbon. The spatial and seasonal differences in the composition of phytoplankton species, coupled with the occurrence of potentially toxic species and bloom densities of H. rotundata suggest that important changes have occurred in the phytoplankton assemblage that likely have affected the food web of these eutrophic bays.

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