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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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A study on the occurrence of Asian open bill stork, Anastomus oscitans in particular tree species at Nature Park, Kolkata, India

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Das A., Sarkar S., Banerjee K., Nandy A., Talapatra S. N., Swarnakar S.
International Letters of Natural Sciences
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2014
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tom 22
The trees support many bird and animal species while the survival of urban-dwelling species e.g. bird species dominate over others. This particular Nature park in Kolkata is the habitat of birds and fish species suggesting a better environment for food chain maintenance. The Asian open bill stork, Anastomus oscitans among other bird species is a common and provides ecosystem health indicator. The present study aims to understand the occurrence and population nos. of Asian open bill stork on particular tree species surrounding wetlands at Nature Park, Kolkata, India. Our results clearly indicate that a total population of this bird species having 671 nos. on the particular trees but not in all other available trees in the study area. In conclusion, present research emphasizes a novel occurrence and higher population of the A. oscitans being observed on the basis of the presence of particular tree species, though no attempt has been made on physico-chemical properties of present water and microclimate within the park. Therefore, further research planning should be oriented considering the physico-chemical impacts as well as local microenvironment along with human interaction as visitors in such a way so that these barriers cannot affect nesting and breeding of those species as eco-indicator. Also further relevant research is needed to emphasize on the conservation of these specific tree species to increase population of Asian open bill stork, A. oscitans in Nature park.
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On the long-term variability of temperature trends and changes in surface air temperature in Kolkata Weather Observatory, West Bengal, India

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Khan A., Chatterjee S., Bisai D.
Meteorology Hydrology and Water Management. Research and Operational Applications
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2015
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tom 03
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nr 2
The impact of climate change on annual air temperature has received a great deal of attention from climatologists worldwide. Many studies have been conducted to illustrate that changes in temperature are becoming evident on a global scale. Air temperature, one of the most important components of climate parameters, has been widely measured as a starting point towards the apprehension of climate change and variability. The main objective of this study is to analyse the temporal variability of mean monthly temperature for the period of 1941 to 2010 (70 years). To detect the magnitude of trend in mean monthly temperature time series, we have used non-parametric test methods such as The Mann-Kendall test, often combined with the Theil-Sen’s robust estimate of linear trend. Whatever test is used, the user should understand the underlying assumptions of both the technique used to generate the estimates of a trend and the statistical methods used for testing. The results of this analysis reveal that four months – January, February, March and December – indicate a decreasing trend in average temperature, while the remaining eight months have an increasing trend. The magnitude of Mann-Kendall trend statistic Zc for this declining temperature and the magnitude of slope for the months of January, February and December are confirmed at the high significance levels of α = 0.001, 0.01 and 0.1 respectively. Though, the overall trend is positive for monthly as well as seasonally efficient time series.
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Avifaunal diversity in two residential localities of Kolkata, India

86%
Chattopadhyay R., Ghoshal S.
International Letters of Natural Sciences
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2015
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tom 48
Avifauna in two different residential localities of Kolkata viz. Cossipore of North Kolkata and Dhakuria of South Kolkata was done in twelve months period from December, 2013 – November, 2014 to get some idea about the present avian diversity of the city. Total forty eight species of birds belonging to twenty five families were identified from the two sites and recorded along with their abundance in this study. Fluctuations in abundance of bird fauna between the study areas were also recorded which may be attributed to the loss of proper habitat for foraging and nesting due to continuous urbanization and increased pollution rates.
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Assessment of antimutagenic avenue and wild plant diversity on roadside near Nature Park, Kolkata, India

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Das S., Benerjee K., Nandy A., Nath Talapatra S.
International Letters of Natural Sciences
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2015
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tom 02
The study of diversity of plants in an urban area is a suitable measure of the terrestrial ecosystem. The study of avenue and wild plants diversity is an important research work, which provides knowledge about naturally occurring chemicals in plants, to protect against mutation, cancer and other diseases. These are commonly called as phytochemicals and the natural chemical ingredients are potent to use in antimutagenicity. The present study aims to understand the occurrence and population nos. of different avenue and wild plants planted or natural on roadside near Nature Park, Kolkata, India. The results clearly indicate that a total population of these plant species are having 282 nos. in the study area. Various literatures clearly revealed that these plants and/or their parts have potent antimutagenic properties by the presence of several phytochemicals. In conclusion, present preliminary research emphasizes an occurrence of antimutagenic avenue and wild plants on roadsides, containing natural chemical ingredients. Previous research works confirmed that toxins or mutagens or carcinogens may cause mutation that leads to cancer. The present study is a preliminary assessment of antimutagenic avenue and wild plant species diversity that have not yet been studied in that particular geographical area. The present study also suggested that avenue and wild plants are suitable for antimutagenic potential along with aesthetical view of human as well as ecosystem support. Therefore, biodiversity study, phytochemicals estimation and conservation of these particular plant species and/or different antimutagenic species in other local area viz. roadsides, parks, forests etc. might be relevant because the plant species can be used for herbal medicine in human healthcare as well as to prevent mutation and cancer.
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Assessment of flower visiting insects diversity as pollinators in two parks, Kolkata, India

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Chowdhury S., Sarkar S., Nandy A., Talapatra S. N.
International Letters of Natural Sciences
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2014
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tom 10
Insects are depends upon autotrophs and they attract by the flowers colour and shape as pollinator. This is a mutual relationship between flowers and insects. The present study aims to determine flower visiting insect diversity as pollinators in two parks as biomonitoring of automobile air pollution exposure, landscape changes and/or human interactions. The study areas were selected as per heavily-populated neighborhoods, nearby office buildings, nearby roads and continuous vehicular movements, human interactions as visitors, where fences and high levels of human disturbance are common. The study was carried out at 2 sampling stations viz (i) Elliot park and (ii) Agri-Horticulture Society. The flower species were selected viz. Helianthus annuus, Petunia sp. and Buganvilia spectabilis planting above mentioned areas because these species are more common among other species. In each flower, diversity of visiting insects were studied by qualitative and quantitative assessment. Indices were Species richness, Index of Dominance, Relative abundance, Shannon-Wiener Diversity Index and Evenness Index for insects for all selected sites were calculated using the statistical formulae. The present results clearly indicate that the flower visiting insects are very less in numbers on three flowering species and index values were decreased. This study is a preliminary assessment of flower visiting insects diversity but further researches are needed in relation to pollination efficiencies of flower visiting insects and biochemical and genetic damage study of flowers as well as air pollution load by using instruments. It was concluded that three flowering species viz. sunflower, petunia and bougainvillea are very common both the parks but insect visitors are common but present less in number, which may be due to the vehicular pollution and/or human interference and/or landscape changes due to nearby neighborhood blocks, office and residential buildings etc.
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Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Ethological study of flower visiting insects in two parks, Kolkata, India

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Sarkar S., Nandy A., Talapatra S. N.
International Letters of Natural Sciences
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2014
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tom 12
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nr 1
Flower visiting insects attract by the flowers colour, shape, size and fragrance as pollinator. This is a mutual relationship between flowers and insects. The present study aims to know behavioural response or ethology of flower visiting insect in relation to particular flower and/or probable atmospheric changes in two managed parks, Kolkata, India. The study areas were selected as per heavily-populated neighborhoods, nearby office buildings, nearby roads and continuous vehicular movements, human interactions as visitors. The study was carried out at 2 sampling stations viz (i) Elliot park and (ii) Agri-Horticulture Society. The flower species were selected viz. Helianthus annuus (sunflower), Petunia sp. (petunia) and Buganvilia spectabilis (Buganvilia) planting above mentioned areas because these species are more common among other species. In each flower, behavioural response or ethology of visiting insects were studied by visual observation and total 10 flowers of each species were observed randomly. The present results clearly indicate that various insects were majorly showed foraging and feeding behaviour and only mating behaviour was found in two species. This study is a preliminary assessment of flower visiting insects’ ethology but further researches are needed in relation to pollination efficiencies of flower visiting insects in the particular flower and air pollution load nearby area by using instruments. It was concluded that insect visitors are showing foraging and feeding behavior but only two species were showed mating behaviour, which may be due to the vehicular air pollution because two parks are located nearby roads and continuous vehicular movements were observed.
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Preferences for different types of offal by Black Kites Milvus migrans from urban garbage dumps of Kolkata, India

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Mazumdar S., Ghose D., Saha G. K.
Acta Ornithologica
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2018
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tom 53
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nr 2
Facultative scavengers often forage on organic wastes from urban dumps. Despite being a major scavenging raptor in many urban areas, studies on Indian subspecies of Black Kites Milvus migrans govinda are very few. We studied the pattern of offal preference by Black Kites foraging in the dumping sites adjoining two major markets of Kolkata, India through cafeteria experiments, where successful foraging events and abundance of foraging Black Kites were recorded. We also carried out questionnaire surveys among 156 meat and fish sellers of 32 markets of this area to assess their offal disposal practice and understand their attitude towards Black Kites. During questionnaire surveys majority of the respondents (77.92%), indicated that Black Kites consume various kinds of offal, particularly chicken offal from garbage dumps of Kolkata. 51.92% respondents opined that Black Kite population has declined in Kolkata, and 41.03% of them believe such decline is due to food scarcity. Still many respondents (64.74%) sell their offal, which reflect their indifferent attitude towards this scavenging raptor. During 'cafeteria experiments, we noticed that foraging kites pick up small pieces of offal from the garbage dumps, particularly chicken, mutton and fish offal (in 15.45 ± 7.749,9.7 ± 4.542 and 9.95 ± 4.951 successful foraging events/h respectively). Energy content (cal/g) of sun-dried samples of each type of offal substances revealed that the energy (calorie) of swine offal was highest followed by beef offal, mutton offal, chicken offal and fish offal. In spite of being energetically rich, beef and swine offal were less selected by Black Kites possibly because they are visibly larger than other offal, thus requires greater handling time and invites higher risk of kleptoparasitism. Successful foraging events were significantly influenced by offal type, but not by months, study sites or by the relative abundance of foraging Black Kites.
8
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Assessment of bird diversity as bioindicators in two parks, Kolkata, India

58%
Chowdhury R., Sarkar S., Nandy A., Talapatra S. N.
International Letters of Natural Sciences
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2014
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tom 11
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nr 2
The trees of parks and gardens support many species, the survival of urban-dwelling species mainly bird species. Birds amongst other species provide a wide range of environmental and social functions to cities and urban dwellers. The present study aims to know bird diversity in two parks as bioindicator of automobile air pollution exposure, landscape changes and/or human interactions. The study areas were selected as per heavily-populated neighborhoods, nearby office buildings, nearby roads and continuous vehicular movements, human interactions as visitors, where high levels of human disturbance are common. The study was carried out at 2 sampling stations viz (i) Elliot park and (ii) Agri-horticulture Society. The bird species diversity was studied by qualitative and quantitative assessment. Indices were Species richness, Index of Dominance, Relative abundance, Shannon-Wiener Diversity Index and Evenness Index for birds for all selected sites were calculated using the statistical formulae. The present results as bioindicators bird species clearly indicate that the bird species are very few in numbers in both the parks. When comparison made between both the parks, it was observed less number of bird varieties (16 types) in Elliot park than varieties (9 types) more less in number in Agri-horticulture society. This study is a preliminary assessment of bird diversity but further researches are needed in relation to biochemical and genetic damage study as well as air pollution load by using instruments. In the present study it was concluded that the less numbers of birds and their different diversity indices were found a decreasing trends, though there no attempt has been made on physico-chemical properties of present air pollutants. The less number of varieties of bird species are as tolerant bioindicators, which may be due to the vehicular pollution and/or human interference and/or landscape changes due to nearby neighborhood blocks, office and residential buildings, continuous movement of vehicles etc.
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Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Assessment of morphological damages of leaves of selected plant species due to vehicular air pollution, Kolkata, India

58%
Nandy A., Talapatra S. N., Bhattacharjee P., Chaudhuri P., Mukhopadhyay A.
International Letters of Natural Sciences
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2014
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tom 04
The present study deals to know morphological damages of leaves of four selected plant species near roadside due to vehicular air pollution in Kolkata, India. The selected plant species are Ficus bengalensis, Ficus religiosa, Alstonia scholaris and Neolamarckia cadamba as these are very common as avenue trees. The study area was selected as per Low vehicular load (LVL) as control area, moderate vehicular load (MVL) area, high vehicular load (HVL) area and heavy vehicular load (HeVL) These three sampling stations were selected on the basis of moderate, high and heavy traffic density and continuous vehicular movement as per visualization. The control area was considered as time dependent vehicular movement due to less traffic density. The morphological damages with special reference to length (L), breadth (B) and L/B ratio and visible injuries in leaves. The visible injuries such as pigmentation, chlorosis, necrosis and burning of leaves of four selected species is documented. There was an increasing and decreasing tends in all four plant species at all three vehicular emission exposed sites (MVL, HVL and HeVL) compared to control site (LVL). In all experimental sites such as MVL, HVL and HeVL, the extra growth and reduction pattern significantly (P < 0.001, 0.01 or 0.05) observed when compared to control site (LVL) for L, B and L/B ratio. The visible injuries (in %) of leaves were also observed in increasing trends. This study is a preliminary assessment of tolerant species that already have been used in greenbelt development to protect air pollutants as well as biological monitoring to know exact load of automobile air pollution but further researches are needed in relation to biochemical and genetic damage study. It was observed that out of four selected species Ficus bengalensis, Alstonia scholaris and Neolamarckia cadamba are more tolerant species and Ficus religiosa is a less tolerant species because of these may have fighting abilities by waxy coatings, accumulation and degradation abilities to vehicular air pollution at all exposed area when compared to control area.
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