Total zooplankton biomass and the constituent species under the major taxa in relation to hydrographic conditions in the Hooghly estuarine complex were studied around Sagar Island during March 1979 to February 1981. Higher numerical counts and biomass of zooplankton occurred during high saline premonsoon period. During monsoon efflux most of the stenohaline organisms disappeard and only the low salinity species alongwith the euryhaline ones were able to thrive in the estuary. Copepods constituted the most predominant portion of zooplankton biomass throughout the year. Two peaks of zooplankton were invariably noticed-primary major peak during June/July and January/February showed the secondary major peak. © 1986 Indian Academy of Sciences.

S K SARKAR

B N SINGH

A CHOUDHURY

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Composition and variations in the abundance of zooplankton in the Hooghly estuary, West Bengal, India

Proceedings: Animal Sciences

Metal pollution is a subject of growing concern as it affects the whole food chain of an ecosystem by bioaccumulation. Growing industrialization and anthropogenic intervention have put tremendous pressure on self-sustaining ecosystems worldwide. Sundarbans mangrove estuary, being a UNESCO World Heritage site, suffers severely from anthropogenic stress, urbanization, ecotourism, overexploitation of natural resources and discharges of industrial as well as municipal waste products. Our study unfolds the extent of metal pollution in the sediment of this estuarine mangrove ecosystem and also investigates the source and distribution of these metals. Extensive samplings were performed during three major seasons, namely pre-monsoon, monsoon, and post-monsoon for two consecutive years at ten sampling stations along the major river networks of the mangrove estuary. Seasonal variations of these metals, physicochemical properties, and soil texture studies were performed to explore the sediment quality of the study area. Positive correlation was observed between the pollutants and siltation. Several environmental indices were investigated to explore the degree of metal pollution which revealed contamination of Cd, Cr, and Pb to cross the permitted safe index in the study area. Pollution load index indicates the spatial as well as seasonal variation of eco toxic metal load along the course of the rivers. Statistical analyses such as principal component analysis and correlation matrix identified different sources for metal contamination. Almost 700 tannery industries are located in the upstream region of the rivers, and several small- and large-scale battery industries seem to be the main possible source for Cd, Cr, and Pb pollution. Analysis of the results indicates the alarming condition of this heritage site. The metal concentrations beyond toxicity thresholds are responsible for gradual deterioration of this estuarine mangrove which may only be protected by developing sustainable management planning. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.

Environmental Science and Pollution Research

Spatio-temporal variability and source identification for metal contamination in the river sediment of Indian Sundarbans, a world heritage site

The spatiotemporal distribution, diversity and biomass of the choreotrich ciliate tintinnid, the ubiquitous planktonic protist, were analysed from nine sampling sites (=252) of diverse environmental stresses along the Hooghly Estuary, eastern part of India during March 2012 to August 2014. Among 32 identified tintinnid species, the agglomerated genera Tintinnopsis (20 sp), dominated the community (∼62%) followed by Tintinnidium (2 sp), Leprotintinnus (2 sp), Codonellopsis, Stenosemella, Helicostomella, Favella, Eutintinnus, Metacylis, Dadayiellaand Wangiella (each comprising single species). A wide range of seasonal variations in tintinnid abundance was recorded maximum (2067±893 ind. l−1) for Tintinnopsis beroidea and minimum (11±4 ind. l−1) for Metacylis sp. during the investigation period. The biomass and daily production rate of tintinnid ranged from 0.004–2.764 μg C l−1 and 0.04–3.54 μg C l−1  day−1 respectively. An overall dominance and diversity of the small-sized tintinnid (lorica length &lt;76 μm) belonging to the genera Tintinnopsis sp., Tintinnidium sp., Codonellopsis sp., Wangiella sp., Eutintinnus sp., Metacylis sp. and Helicostomella sp. was pronounced, accounting ∼66% of the total tintinnid abundance. K-dominance curves were plotted against log rank k, showed species dominance over the investigated sites. The multidimensional scaling (MDS) Canonical Analysis of Principal coordinates (CAP) highlighting a significantly different spatial distribution of tintinnid. Principal Component Analysis (PCA) map showed clustering of core species with chl a and nitrate and could be considered as the crucial factors controlling the distribution and seasonal patterns of tintinnid. Biota-environment (BIOENV) analyses also reveal that these two parameters were the significant causative factors, suggesting that tintinnid may be used as a bioindicator for discriminating water quality in this estuarine system. The study provided detailed information of microzooplankton which enhances our understanding regarding its crucial role in marine ecosystem and complex biotic interactions for maintaining the ecological and economic stability. © 2017 Elsevier B.V.

Regional Studies in Marine Science

Environmental impact on diversity and distribution of tintinnid (Ciliata: Protozoa) along Hooghly Estuary, India: A multivariate approach

The study is the first documentation of seasonal variations in species composition, abundance and diversity of tintinnid (Ciliata: Protozoa), in relation to water quality parameters along the stretch of the Hooghly (Ganges) River Estuary (HRE), eastern coastal part of India. A total of 26 species (22 agglomerated and 4 non-agglomerated) belonging to 8 genera has been identified from 8 study sites where Tintinnopsis (17 species) represented the most dominant genera, contributing up to 65 % of total tintinnid community followed by Tintinnidium (2 species), Leprotintinnus (2 species) and Dadayiella, Favella, Metacylis, Eutintinnus and Helicostomella (each with solitary species). The maximum (1,666 ind.l-1) and minimum (62 ind.l-1) abundance of tintinnids was recorded during post-monsoon and monsoon, respectively. A distinct seasonal dynamics in terms of biomass (0.005-2.465 μg C l -1) and daily production rate (0.04-3.13 μg C l-1 day-1) was also noticed, accounting highest value during pre-monsoon. Chlorophyll a and nitrate were found to be potential causative factors for the seasonal variations of tintinnids as revealed by a stepwise multiple regression model. The result of ANOVA showed a significant variation between species abundance and months (F=2.36, P≤0.05). k-dominance curves were plotted to determine the comparison of tintinnid dominance between the investigated stations. Based on a principal component analysis (PCA), three main groups were delineated with tintinnid ciliates and environmental parameters. The changes in lorica morphology in terms of temperature and salinity, recorded for three dominant species, provided information on the ecological characteristics of the species assemblage in this estuarine system. © 2014 Springer Science+Business Media Dordrecht.

Environmental Monitoring and Assessment

Seasonal variations in species composition, abundance, biomass and production rate of tintinnids (Ciliata: Protozoa) along the Hooghly (Ganges) River Estuary, India: A multivariate approach

There are no differences of opinion in saying that the climate of the planet Earth is changing with the passage of time. Although several factors beyond our control (like variations in the Earth's orbital characteristics, volcanic eruptions, variations in solar energy output and plate tectonics) do play a major role in this change, the infl uence of human intervention cannot be ignored. The rapid industrialization and urbanization in the recent era has hiked up the concentration of greenhouse gases in the atmosphere, and as the successive events, the temperature has increased, the seawater has expanded, the agricultural productivity has gone down, the existing socio-economic profi le has altered, the vector-borne diseases have proliferated and the biodiversity of the world oceans and estuaries has changed. Question arises whether these chain reactions are irreversible in nature. Question also arises regarding the rate of alteration (acceleration or retardation) of environment around us, and we are uncertain about these answers. All the nations of the world have converged on a common platform to fi ght this invisible demon with irregular and uncertain behaviour. There is no point other than adaptation to minimize the impact of climate change. Adaptation here refers to the ability to respond and adjust to actual or potential impacts of changing conditions of the climate in ways that moderate harm or takes advantage of any positive opportunities that the climate may afford. It is therefore a mode of coping with the surrounding environment through development and alteration/modifi cation of some attitude, habit, habitat, etc. Even changes in the policy level or planning processes or decision-making processes are also the part of adaptation. This manuscript critically focuses on all the events of climate change starting from causes to effects on the matrix of mangrove ecosystem. Sundarbans being the biggest mangrove chunk of the globe has been used as the test bed to distinguish between human factors (effects of dam construction, barrage discharge, industries, etc.) and natural causes of environmental change, which often creates a noise while explaining the issue of climate change. The emphasis has been given on Indian Sundarbans because the subcontinent has been identifi ed as one among 27 countries which are most vulnerable to the impact of global-warming-related accelerated sea-level rise (UNEP 1989). Available literatures state that the sea level is rising at the rate of 3.14 mm/ year in Indian Sundarbans, which is greater than the average sea-level rise in rest part of the globe. The Indian Sundarbans sustains 34 true mangrove species, which not only act as the line of defence against sea-level rise, cyclones and tidal surges, but their role in carbon sequestration and minimization of carbon dioxide at the regional level has been critically analyzed in the present book. Apart from ecological approach in reducing carbon dioxide level of the atmosphere, the existing policies and laws have also been discussed in the matrix of Indian subcontinent. In India, there are no laws, policies, insurance or funds to protect, compensate and rehabilitate the vulnerable communities related to climate change or weather extremes. This creates a situation where the properties and life along the coastline are exposed to extreme risks. Building of cyclone shelters and tidal surge warning system along with a well-orchestrated disaster management plan can ameliorate the adversity of impact to a certain extent. The authors of the present book feel the necessity of introducing some kind of climate insurance policies (like health insurance and car insurance) to cover the risk of climate-change-related disasters. The book has its own individuality not because of the lucidness of language and presentation of relevant case studies but for bringing in frontline the long-term data (30 years) of this biggest mangrove chunk, which have just started to see the light of publication. Criticism and debates are the hallmarks of any climate-change-related books, as a 'noisy zone', always lies in such subjects, where it is diffi cult to segregate the effects of climate change from man-made intervention. In this connection, the Farakka dam issue has been discussed very clearly with its major role in regulating the salinity at the confl uence of the Hooghly-Bhagirathi system and Bay of Bengal. Finally the untapped marine and estuarine living resources (like seaweeds and edible oyster) have also been highlighted with the aim to develop alternative livelihood schemes as steps towards adapting to a new situation of rising salinity. © Springer India 2013. All rights are reserved.

Sensitivity of Mangrove Ecosystem to Changing Climate

Sensitivity of mangrove ecosystem to changing climate

The two great rivers of India the Ganga and the Brahmaputra form their estuary at the lower part of West Bengal and most of the part of this estuarine system is surrounded by Sundarban mangrove forest. This mangrove based estuarine ecosystem harbors a large number of fin fishes i.e. more or less 267 species of fishes which belong under 81 families. Estuary's own ecological characters and mangrove's all beneficial features support this high species diversity here. But due to continuously increasing natural and anthropogenic stresses, nowadays this entire species community faces a tremendous problem of extinction. 82 species under 24 families loss their juveniles in a significant number regularly due to wild harvest of lucrative prawn seeds. The present article aims to review the roles of estuary and mangroves in enrichment of finfish diversity and the possible threats causing harm to the same. © 2012 Springer Science+Business Media Dordrecht.

Journal	Proceedings: Animal Sciences
Publisher	-
ISSN	0253-4118