Intra-monsoonal variation of zooplankton population in the Sundarbans Estuarine System, India

A new pilargid species, Sigambra sundarbanensis sp. nov., is described from the rivers Matla and Thakuran, in the central Indian sector of the Sundarbans Estuarine System. This species is characterized by several characters such as the starting position of the notopodial hooks, the length of the median antenna and the variation in number of the neuropodial chaetae. These characters distinguish the new species from its congeners. Some parapodial glands have been found in individuals of this species. The new species closely resembles Sigambra parva (Day, 1963). Additionally, an updated key of genus Sigambra is provided, along with a table indicating their morphological variations and a global map showing their type localities.

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The postmonsoon carbon biogeochemistry of estuaries under different levels of anthropogenic impacts

10.5194/bg-2018-310 ◽

2018 ◽

Author(s):

Manab Kumar Dutta ◽

Sanjeev Kumar ◽

Rupa Mukherjee ◽

Prasun Sanyal ◽

Sandip Mukhopadhyay

Keyword(s):

Anthropogenic Impacts ◽

River System ◽

Phytoplankton Production ◽

Estuarine System ◽

Phytoplankton Productivity ◽

Run Off ◽

Carbon Biogeochemistry ◽

Different Levels ◽

The Sundarbans

Abstract. The different aspects of carbon biogeochemistry were studied during the postmonsoon at the Hooghly-Sundarbans estuarine system, a part of the Ganga-Brahmaputra river system located in the northeastern India. The study focused on understanding the differences in carbon biogeochemistry of estuaries undergoing different levels of anthropogenic stress by investigating anthropogenically influenced Hooghly estuary and mangrove-dominated estuaries of the Sundarbans. The salinity of well oxygenated (%DO: 91–104 %) estuaries of the Sundarbans varied over a narrow range (12.74–16.69) during postmonsoon relative to the Hooghly (0.04–10.37). Phytoplankton productivity and carbonate precipitation and/or dissolution were dominant processes controlling DIC dynamics in different parts of the Hooghly, whereas signal for mangrove derived DIC removal was observed in the Sundarbans. Influence of groundwater on estuarine DIC biogeochemistry was also observed in both the estuaries with relatively higher influence at the Hooghly than Sundarbans. In both estuarine systems, DOC behaved non-conservatively with ~ 40 % higher DOC level in the Hooghly compared to the Sundarbans. No significant evidence of phytoplankton production on DOC level was found in these estuaries, however signal of DOC input through pore-water exchange at the Sundarbans was observed. Relatively lower δ13CPOC at the Hooghly compared to the Sundarbans suggest relatively higher terrestrial influence at the Hooghly with a possibility of in situ biogeochemical modifications of POC at the Sundarbans. The freshwater run-off coupled with in situ aerobic OC mineralization controlled estuarine pCO2 level at the Hooghly, whereas the same was principally exogenous for the Sundarbans. The entire Hooghly-Sundarbans system acted as source of CO2 to the regional atmosphere with ~ 17 times higher emission from the Hooghly compared to Sundarbans. The present study clearly establishes the dominance of anthropogenically influenced estuary over relatively pristine mangrove dominated one in the regional greenhouse gas budget and climate change perspective.

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Tidal variations in the Sundarbans Estuarine System, India

Journal of Earth System Science ◽

10.1007/s12040-013-0314-y ◽

2013 ◽

Vol 122 (4) ◽

pp. 899-933 ◽

Cited By ~ 30

Author(s):

MEENAKSHI CHATTERJEE ◽

D SHANKAR ◽

G K SEN ◽

P SANYAL ◽

D SUNDAR ◽

...

Keyword(s):

Estuarine System ◽

Tidal Variations ◽

The Sundarbans

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Variation of salinity in the Sundarbans Estuarine System during the Equinoctial Spring tidal phase of March 2011

Journal of Earth System Science ◽

10.1007/s12040-021-01636-9 ◽

2021 ◽

Vol 130 (3) ◽

Author(s):

Meenakshi Chatterjee ◽

D Shankar ◽

V Vijith ◽

G K Sen ◽

D Sundar ◽

...

Keyword(s):

Estuarine System ◽

Tidal Phase ◽

The Sundarbans

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The post-monsoon carbon biogeochemistry of the Hooghly–Sundarbans estuarine system under different levels of anthropogenic impacts

Biogeosciences ◽

10.5194/bg-16-289-2019 ◽

2019 ◽

Vol 16 (2) ◽

pp. 289-307 ◽

Cited By ~ 6

Author(s):

Manab Kumar Dutta ◽

Sanjeev Kumar ◽

Rupa Mukherjee ◽

Prasun Sanyal ◽

Sandip Kumar Mukhopadhyay

Keyword(s):

Organic Matter ◽

Anthropogenic Impacts ◽

C3 Plants ◽

Estuarine System ◽

Phytoplankton Productivity ◽

Organic C ◽

Hooghly Estuary ◽

Post Monsoon ◽

Different Levels ◽

The Sundarbans

Abstract. The present study focused on understanding differences in the post-monsoon carbon (C) biogeochemistry of two adjacent estuaries undergoing different levels of anthropogenic stresses by investigating anthropogenically influenced Hooghly estuary and mangrove-dominated estuaries of the Sundarbans in the north-eastern India. The salinity of well-oxygenated estuaries of the Sundarbans (DO: 91 %–104 %) varied over a narrow range (12.74–16.69) relative to the Hooghly estuary (0.04–10.37). A mixing model suggested a combination of processes including freshwater intrusion, carbonate precipitation and carbonate dissolution to be a major factor controlling dissolved inorganic C (DIC) dynamics in the freshwater regime of the Hooghly, whereas phytoplankton productivity and CO2 outgassing dominated in the mixing regime. In the Sundarbans, the removal of DIC (via CO2 outgassing, phytoplankton uptake and export to the adjoining continental shelf region) dominated its addition through mineralization of mangrove-derived organic C. The concentration of dissolved organic C (DOC) in the Hooghly was ∼40 % higher than in the Sundarbans, which was largely due to the cumulative effect of anthropogenic inputs, DOC–POC interconversion and groundwater contribution rather than freshwater-mediated input. The measured δ13CPOC in the Hooghly suggested particulate organic matter contributions from different sources (freshwater runoff, terrestrial C3 plants and anthropogenic discharge), whereas the contribution from C3 plants was dominant at the Sundarbans. The significant departure of δ13CPOC from typical mangrove δ13C in the mangrove-dominated Sundarbans suggested significant particulate organic C (POC) modification due to degradation by respiration. The average pCO2 in the Hooghly was higher by ∼1291 µatm compared to the Sundarbans with surface runoff and organic matter degradation by respiration as dominant factors controlling pCO2 in the Hooghly and Sundarbans, respectively. The entire Hooghly–Sundarbans system acted as a source of CO2 to the regional atmosphere with ∼17 times higher emission from the Hooghly compared to the Sundarbans. Taken together, the cycling of C in estuaries with different levels of anthropogenic influences is evidently different, with significantly higher CO2 emission from the anthropogenically influenced estuary than the mangrove-dominated ones.

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Unravelling the spatio-temporal variation of zooplankton community from the river Matla in the Sundarbans Estuarine System, India

Oceanologia ◽

10.1016/j.oceano.2020.03.005 ◽

2020 ◽

Vol 62 (3) ◽

pp. 326-346 ◽

Cited By ~ 1

Author(s):

Tanmoy Nandy ◽

Sumit Mandal

Keyword(s):

Temporal Variation ◽

Zooplankton Community ◽

Estuarine System ◽

Spatio Temporal ◽

The Sundarbans

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Variability in the zooplankton assemblages in relation to environmental variables in the tidal creeks of Sundarban estuarine system, India

10.21203/rs.3.rs-183370/v1 ◽

2021 ◽

Author(s):

Sanghamitra Basu ◽

Pranab Gogoi ◽

Subarna Bhattacharyya ◽

Lohith Kumar K. ◽

Sanjoy Kumar Das ◽

...

Keyword(s):

Community Dynamics ◽

Diversity Index ◽

Zooplankton Community ◽

Mean Value ◽

Estuarine System ◽

Anthropogenic Pressure ◽

Tidal Creeks ◽

Water Parameters ◽

Zooplankton Population ◽

Α Diversity

Abstract The present study illustrates a holistic account of zooplankton community dynamics in relation to physico − chemical variables in the tidal creeks of Indian Sundarbans estuarine system. Out of 11 water parameters, seven parameters (Temp., salinity, DO, turbidity, PO4 − P, NO3 − N and NO2 − N) differed significantly (p ≤ 0.05) among seasons. A total of 63 zooplankton taxa were recorded with the predominance of Copepoda, varying in ranges from 59.55 to 73.13% of the total zooplankton population. PERMANOVA design depicted the significant variations of zooplankton population both spatially (F = 2.313; p = 0.001) and temporally (F = 6.107; p = 0.001). Out of 41 species of Copepoda recorded, 14 species (Paracalanous parvus, Parvocalanous dubia, Bestiolina similis, Acrocalanous gibber, A. gracilis, Acartia erythraea, A. spinicauda, Pseudodiaptomus serricaudatus, P. annandalei, P. aurivilli, Oithona brevicornis, O. similis, Longipedia weberi and Microsetella norvegica) indicated as ‘characterizing species’ in the creek environment, and highlighted the euryhaline nature as well as broad range of thermal tolerance of these species. β – diversity index (Index of Multivariate dispersion) reflected higher values (β = >1) in the creeks (S4, S2 and S6), those are experienced with high anthropogenic pressure. On the whole, the calculated mean value of α − diversity (dʹ=4.07; H'=2.31) indicated ‘good’ zooplankton diversity. Water parameters viz., Temp., salinity, DO, turbidity, PO4 − P and NO3 − N were found to have influence on the distribution, abundance and diversity of zooplankton in the creeks. More specifically, the linear model (DistLM) exhibited two variables viz., temperature and salinity were the primary controlling factors in shaping the zooplankton community compositions in the creek environment.

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