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Abstracts of recently published papers

Limnology/Wetland Ecology

Aquatic Ecosystem Health & Management, 5(2) 191–203, 2002 © 2002 AEHMS 1463-4988/02 $12.00 + .00
DOI: 10.1080 /14634980290031848
Buddhadeb Chattopadhyay, A. Chatterjee, S. K. Mukhopadhyay

Abstract: This work was initiated to study the extent of toxic metal contamination of the east Calcutta wetland ecosystem. BOD, COD, TDS, Conductivity, TSS, Total hardness, pH were recorded from six different spots on the sewage carrying canals including an industrial effluent-fed fish pond in the eastern Calcutta (lat. 22o33/ -22o 40/ N; long. 88o 25/ -88o 35/ E). Concentrations of metals such as Pb, Cu, Cr, Zn, Fe, Mg and Mn in wastewaters, and water of adjacent sewage-fed fish tank were also determined. Concentration of these hazardous metals in soil/sludge and accumulation of these metals in plant and fish tissues were also studied. A number of hazardous metals in wastewater like Pb, Zn, Cu, Mn, and Fe reduced to the extent of 25-45% while total Cr reduced over 95%, on the course of 40 km long journey of the composite wastewater from the sources to rivermouth via the wastewater carrying canal and also in stabilization pond were recorded. 99% Cr and 65% Zn reductions in soil/sediment were recorded between sources and final discharge sites.

Keywords : Wastewater, solid wastes, heavy metals, fish, plant, EIA.

Limnochemical Factors Influencing the Seasonal Population Density,
Secondary Production, and Calcium-to-Tissue Ratio in the
Freshwater Limpet Septaria lineata (Archaeogastropoda: Neritidae)
Turk J Zool, 32 (2008) 245-252

Abstract: The distribution, secondary production, and calcium:tissue (Ca:tissue) ratio in relation to limno-chemical factors were studied in a freshwater limpet (Septaria lineata) population from the west bank of the River Hooghly, West Bengal, India, for 2 successive years. Total hardness, chloride, pH, and phosphate were shown to be significant in Pearson’s correlations in influencing the abundance of the limpet population. Annual production for the 2 successive years was 10.3 g m-2 and 9.5 g m-2, respectively. The annual turnover ratios, the ratios of annual production (P) and annual standing crop (B), ‘P/B’, were calculated to be 2.06 and 1.67, while annual turnover times were 177 days and 219 days, respectively. The ratio of whole animal shell calcium content to tissue dry weight (shell Ca:tissue ratio) changed with age and size class, but these changes were largely restricted to early growth and did not significantly affect individuals over a particular size class (shell height 40-49 mm). Total hardness and chloride were the most important limnochemical factors influencing the shell Ca:tissue ratio.

Key Words: Septaria, freshwater limpet, secondary production, population density, Ganga


Anulipi Aich and Subhra Kumar Mukhopadhyay
THE RING, 30, 1/2: 71-79, 2008, DOI 10.2478/v10050-008-0001-6
ABSTRACT: Avifauna of shola and semi-evergreen forest patches belonging to three different sanctuaries and National Parks in the southern part of Western Ghat range of Tamil Nadu and Keralaw as studied. Altogether 36 species from 17 families were recorded. One globally threatened species (A1), two restricted range species (A2) and one Palearctic-Asian migrant species have been recorded from forest edges during the relatively short study period. The highest population density of 47.59 ind./ha at Varagaliar Shola was followed by 43.69 ind./ha at Anapaddy, 27.53 ind./ha at Karian Shola, and 23.25 ind./ha at Punnumalai Shola. As Punnumalai Shola is least disturbed by human activity it got the highest number of avian families (15) and was followed by Karian Shola (9) and Vargaliar Shola and Anapaddy - 8 in both cases. Punnumalai Shola having varied bird families showed lower dominance (0.075) and higher evenness value (0.957). In contrast, the edge of semi-evergreen forest at Anapaddy, although very much disturbed by various human activities, showed almost comparable diversity value (2.890) to that of Punnumalai Shola (2.913). More open canopy and much vegetational intergradations at the ecotone of semi-evergreen biotope inherently shelter avian community of high diversity. Conversely, the edges of Karian Shola and Varagaliar Shola having much anthropogenic interferences and with edges showing much lower intergradations of vegetations, exhibited a low avian diversity.

Key words: shola, edge species, Western Ghats, hotspot, EBA 123, Biome 10, Palearctic-Asian migrant
Mobility and Bioavailability of Chromium in the Environment: Physico-Chemical and Microbial Oxidation of Cr (III) to Cr (VI)
J. Appl. Sci. Environ. Manage. June, 2010, Vol. 14 (2) 97 - 101
Full-text Available Online at
ABSTRACT: The physico-chemical and microbial characteristics in soil was investigated in order to study the mobility and bioavailability of Chromium in the environment. In the present investigation the role of soil microbes along with some physico-chemical agents (UV ray, Mn and Fe) were studied for possible oxidation of Cr(III) to Cr(VI) in laboratory conditions. Photochemical oxidation of Cr(III) to Cr(VI) was found to be significantly high at the surface level of the soil studied (conversion of Cr6+ in control soil was calculated as 0.15 mg kg-1 dry weight). Metal catalyst also contributed to oxidation of chromium in soil. Conversion of Cr6+ by metal catalysis ranged between 0.00 and 0.08 mg kg-1 dry weight (mean 0.05 mg kg-1 dry weight). However, metal catalysts such as, Fe and Mn together or these metals alone were not as efficient as the microbes or the UV mediated conversion during the given period of exposure (two weeks). The data indicates that microbial conversion of Cr(III) to Cr(VI) varied from 0.12 – 0.18 mg kg-1 dry weight, while mean was 0.14 mg kg-1 dry weight. Since, at the plant root zone, where the UV penetration is negligible, metal catalysts could be inferred to be not much efficient in conversion of Cr(III) to Cr(VI) as compared to microbes. Therefore, the present findings suggested that microbial mediated conversion is the preferred pathway and consequently responsible for root uptake of chromium by plants.

Nanoplankton Colonization on Artificial Substrate in a Large Perennial
Freshwater Pond of West Bengal, India
Utpal Singha Roy and S.K. Mukhopadhyay
European Journal of Applied Sciences, 2 (3): 94-97, 2010
ISSN 2079-2077, © IDOSI Publications, 2010
Abstract: Colonization pattern of nanoplankton was studied over a period of four months in a perennial freshwater pond at Chinsurah, west Bengal, India. Sterilized polyurethane foam (PUF) units were immersed individually at about 15 cm below the water surface and harvested periodically for nano-phytoplankton and micro-rotiferan community. Colonization pattern of both the communities were dynamic in nature with Chlorophyceae being the dominant nano-phytoplanktonic group while, Philodina roseola was recorded as the dominant micro-rotiferan species. Diversity, richness, dominance, similarity indices and succession rate varied widely for both the communities. The community maturation time recorded for nano-phytoplanktonic community and rotiferan community were 21 and 60, days respectively. The present investigation provided an opportunity to understand nanoplankton colonization, growth and succession pattern in tropical freshwater ponds. Moreover, it provided a chance to learn complex community interactions that takes long time in nature in a simplified time efficient manner.

Key words: Nanoplankton, Rotifera, Succession Rate, Phytoplankton, Artificial Substrate
Study of trace metals in Indian major carp species from astewater-fed fishponds of East Calcutta Wetlands
Aquaculture Research, 2011, 1-13 doi:10.1111/j.1365-2109.2011.02800.x

Anulipi Aich, Anindita Chakraborty, Mathumal Sudarshan, Buddhadeb Chattopadhyay & Subhra Kumar Mukhopadhyay

Fish grown in the East CalcuttaWetland (ECW) areas inWest Bengal, India amass waste elements within their body through nutritional uptake and accumulation. The present investigation had been carried out to atudy the extent of accumulation of di¡erent waste elements in tissues of Indian major carps (IMCs) commonly cultured in composite industrial wastewaterfed fishponds in ECW, India. Energy-dispersive X-ray fluorescence spectrometric studies were used to estimate metals like chromium (Cr), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn) and lead (Pb) inwater and sediment of ¢shponds, and in ¢sh tissues (gill, liver and muscle) of three economically important
IMCs, rohu (Labeo rohita), katla (Catla catla) and mrigel Cirrhinus mrigala), collected from contaminated and
control sites. It is evident from the study that mainly liver is the site of maximum accumulation of the elements,
while gill, in most cases, is the site of least metal accumulation in the three IMC species studied. Principal component analysis reveals that Fe and Cr were in the ¢rst component and thereby must be having a major in£uence in trace metals uptake and bioaccumulation. Tissue-speci¢c and species-specific patterns of metal concentration and partitioning were apparent fromour present study.

Keywords: Ramsar site, East Calcutta Wetland, trace metals, ¢sh tissue, Indian major carp

Changes in Densities of Waterbird Species in Santragachi Lake, India: Potential Effects on Limnochemical Variables
Utpal Singha Roy, Abhishek Roy Goswami, Anulipi Aich, and Subhra Kumar Mukhopadhyay
Zoological Studies 50(1): 76-84 (2011),

Abstract: We carried out limnological investigations in relation to anticipated effects of migratory waterbird use in an urban lake 20 km from the East Calcutta Wetlands, a Ramsar site. Twentytwos species of birds used the lake during the migration and wintering periods (Oct.-Mar.) in 3 successive years (2004-2007). The lowest Shannon diversity index value of 0.360 was found in Nov., while the highest of 0.963 was found in Oct. for the pooled data collected during the 3-yr study period. We examined correlations among 7 physical, chemical, and vegetal factors with avian densities. The addition of bird guano increased the nutrients and was rapidly utilized by higher gross primary productivity (GPP) as well as by secondary production of the lake body. Higher rates of both primary and secondary production resulted in the rapid uptake of basic nutrients like phosphate, nitrate, and silicate. We found negative correlations of major nutrients (phosphate, nitrate, and silicate) with both GPP and higher avian densities. Increased areas of open water, which were free of floating vegetation, also likely influenced bird aggregation and the limnochemistry by allowing more space for avian interactions and increased solar input for photosynthesis, respectively.

Key words: Santragachi wetland, Limnochemistry, Waterbirds, East Calcutta Wetlands, Ramsar site.


Manjari Jain, Singha Roy Utpal, S. K. Mukhopadhyay

Vestnik zoologii, 45(2): 153—159, 2011


Abstract: The presence of wildlife fauna and its activities were ascertained with the density of the scat, dung and other markings or droppings of the wildlife abode therein. Attempt was made to find out spatial differences in the activities of the wildlife populations and to comment on the abundance of different preys and predators within shola forests of Western Ghat hill forests, a Biodiversity hotspot in India. An indirect sampling method, Transect Count Method, was employed to count dung/pellet group/scat and other markings in that area. Pachyderms were found to be mostly dominant in Varagaliar and Punnumala shola patches while scats of all the three important predators, viz., tiger (Panthera tigris tigris), Indian wild dog (Cuon alpinus) and leopard (Panthera pardus) were encountered only in Varagaliar shola. Greater abundance was recorded from Indira Gandhi Wildlife Sanctuary than Silent Valley National Park may be because of the restriction of animal movements in the former due to topographical barriers and its existence as isolated shola patches that led to a greater concentration of wild fauna in a relatively segregated forest cover.

Key words: scat, shola, hotspot, topographical barriers, tribal settlements, Western Ghats. 


Antioxidant response to oxidative stress in zooplankton thrived in wastewater-fed ponds in East Calcutta Wetland Ecosystem, a Ramsar site

Abhishek Roy Goswamia,b, Anulipi Aicha, Sudin Pala, Buddhadeb Chattopadhyaya,Siddhartha Dattab

and Subhra Kumar Mukhopadhyay

Toxicological & Environmental Chemistry, 2013
Vol. 95, No. 4, 627–634,


Abstract: The municipal sewage of Calcutta city together with industrial effluents traversed theEast Calcutta Wetlands (ECW) (Ramsar Site No. 1208) for nearly a century. The composite wastewater at the ECW, was used for pisciculture and agriculture after natural stabilization. Such uses have always been thought to be a source of contamination to biota and humans. Some water-borne pollutants generate reactive oxygen species including superoxide radical anion (O2.), hydrogen peroxide (H2O2), and hydroxyl radical (.OH), which are highly reactive and potentially deleterious to biological systems. The present study was initiated to examine the antioxidant activities against oxidative stress during different seasons in body fluids of two zooplankters, Moina micrura and Mesocyclops leuckarti thriving in wastewater-fed ponds of ECW. Results showed significantly higher electrical conductivity, chloride and metal (Cr, Cu, and Pb) concentrations in contaminated wastewater-fed pond (CP) at ECW compared to the uncontaminated village pond (UP). Zooplanktons thriving in CP displayed significantly higher superoxide dismutase and catalase activities at all seasons compared to those in UP. Seasonal variations in antioxidant activities were found to be in agreement with variations in limnochemical factors. Hence, antioxidant activity was used as a biomarker against oxidative damage in plankters surviving under pollutant stress.


Keywords: East Calcutta Wetlands; zooplankton; oxidative stress; antioxidants; biomarker; cladocera; copepoda 


Changes in physicochemical characteristics of wastewater carrying canals after relocation of Calcutta tannery agglomerates within the East Calcutta Wetland ecosystem (a Ramsar site)



International Journal of Environmental Studies, 2013


Abstract: Calcutta Leather Complex (CLC) near Bantala, Calcutta was constructed in the late 1990s. The ostensible purpose was to bring together the widely dispersed and haphazardly located tanning industry of Calcutta in a single location and to facilitate hazardous waste management by establishing a Common Effluent Treatment Plant. Unfortunately, for a number of reasons, the CLC is not yet ully operational. Further, the continued operation of illegal tanneries outside CLC has worsened atters. This study was undertaken to assess the physicochemical conditions of wastewater carrying anals within the East Calcutta Wetland (ECW) ecosystem (a Ramsar site) with special reference to he relocation of tanneries. Results revealed a great change in the values for physicochemical conditions; most changes were statistically significant (p < 0.05) when compared with available data, previous to tannery relocation. Moreover, the amelioration efficiency of ECW ecosystem was found to be mostly disturbed both by the illegal tannery operations and shifting of tannery agglomerates.


Keywords: East Calcutta Wetland ecosystem; Tannery agglomerates; Calcutta Leather Complex 



(Poecilia reticulata) AS A FISH MODEL
Utpal Singha Roy, Anulipi Aich, Buddhadeb Chattopadhyay, Siddhartha Datta, Subhra Kumar Mukhopadhyay

 Environmental Engineering and Management Journal, March 2013, Vol.12, No. 3, 557-563


Abstract: East Calcutta Wetland ecosystem is a Ramsar Site in India covering almost 51 km2 and is one of the largest of its type. This wetland receives a massive load of almost untreated industrial and domestic effluents every day, throughout the year, that has been effectively utilized in pisciculture for having a better yield (2.85 metric tons of fish per 0.01 km2 of water body per annum). The present investigation was carried out to study the toxicity of the untreated effluents discharged from tanneries located at the fringe of East Calcutta wetlands. Guppy (Poecilia reticulata) was chosen as a model fish and was exposed to three different sublethal concentrations (3%, 6% and 9%) of composite tannery effluents (TE) for different time periods (4 days, 7 days and 15 days). Exposed fish livers were analyzed for metallothionein (MT, a ubiquitous metal binding protein), cytochrome P4501A1+1A2 (CYP, a major family of xenobiotic metabolizing enzyme in fish biosystem) and nonspecific cytotoxic cells (NCCs, a major group of innate immune system in fish) expressions applying indirect enzyme-linked immunosorbent assay
(ELISA) procedure. Results showed that expression of all the three chosen biomarkers were significantly dose and time dependent upon tannery effluent exposure. Major significances drawn from the present study was that fish species cultivated in east Calcutta wetland ecosystem are under potential threat of contamination and stress induced by composite tannery effluents that could lead to adverse physiological conditions. Moreover, these findings could be important in terms of designing biomarkers for early environmental warning system and also for monitoring fish health.


Key words: biomarkers, cytochrome P450, innate immunity, metallothionein, tannery effluent









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Background. Metals discharged in wastes from different industries into wetland ecosystems pose a serious threat to the receiving environment. Biotic components grown in the area amass such metals within their body through nutritional uptake and accumulation. The present investigation was carried out to study the extent of accumulation of different waste metals in tissues of cichlids commonly cultured in composite industrial wastewater-fed fishponds (Bheris) in East Calcutta Wetlands (ECW), a Ramsar site in India.

Materials and Methods. AAS studies were employed to estimate metal (Cr, Mn, Fe, Cu, Zn, and Pb) concentrations in water, and bottom sediment of fishponds and fish tissues (gill, liver, muscle, and bones) of cichlids: Nile tilapia, Oreochromis niloticus L. and Mozambique tilapia, O. mossambicus (Peters, 1852), collected from contaminated and control sites.

Results. The concentrations of metals in bottom sediment were found higher than those of the overlying water. It was evident from the experiment that, either bone or liver was the site of maximum accumulation for the elements while muscles were the site of least metal accumulation in both fish species. Chromium, which was a highly publicised contaminant of tannery effluents, showed a similar distribution pattern (muscle < gill < liver < bone) in these fishes. Concentrations of non-essential metals like Pb were highest in Nile tilapia liver (17.9 mg · kg.1) followed by Mozambique tilapia liver (14.7 mg · kg.1). Principal component analysis with Varimax rotation revealed that Fe and Mn were in the first and second component, respectively, to influence metal uptake and bioaccumulation.

Conclusion. Tissue-specific and species-specific patterns of metal concentration and partitioning were apparent from our experimentation. Dendrograms showed two definite clustering pattern, gill and muscle in one cluster with bone and liver in the other, two important organs so far as partitioning (in bone) and detoxification (in liver) were concerned.

Keywords: fish, Cichlidae, Oreochromis niloticus, Oreochromis mossambicus, heavy metals, wastewater, East Calcutta Wetlands, Ramsar site