Search

This study is a real-time hydrogeological investigation to appraise the groundwater scenario and spatial variations of its major physicochemical parameters at the southernmost apical fringe of the Indian Sundarban Biosphere Reserve area in mesoscale during the recent post-monsoon season (PoM). The study was based on the acquisition and analysis of primary field data collected from the southernmost apex of the river Ganga-Brahmaputra-Meghna delta and restricted to the Namkhana Development Block of South 24 Parganas district, West Bengal, India. Twenty-two groundwater samples were collected from bore wells post-monsoon (October 2022). Measurements of major physical parameters were done in situ. Geospatial contour maps representing variations of influencing parameters were prepared. The drinking and irrigation suitability of the water was validated by existing standard equations and plots. Chemical analyses were done to evaluate its hydrochemistry and suitability for drinking and agriculture. Obtained results primarily revealed that TDS and pH are at marginal ranges with significantly alarming concentrations for some major contributing ions, chiefly bicarbonates, and sodium. The overall suitability of groundwater for agriculture, drinking, and domestic purposes differs from acceptable limits. Indiscriminate groundwater exploitation from deeper aquifers for agriculture seemed to be the prime factor responsible for this situation. [ABSTRACT FROM AUTHOR]

Ecotourism is increasingly being promoted as an instrument that helps local socio-economic development and generate revenues to strengthen conservation of critically endangered biodiversity. It is often posited the magic bullet particularly across protected areas in the Global South. In theory, ecotourism can provide economic benefits to economically weaker communities living around protected areas and inspire them to protect the biodiversity in their own interest. This paper, however, provides empirical evidence that the so-called win–win is not an unqualified truism. With a case study on Sundarban Biosphere Reserve, world's largest mangrove biodiversity and home of highly endangered Royal Bengal Tiger, this article examines complexities involved in ecotourism and urges the need to make it context-specific. It assesses ecotourism's ability to provide livelihood alternatives to local communities and how can it help in conservation. The findings demonstrate an unequal, uneven, and skewed accumulation of benefits of ecotourism, often associated with market mechanisms of global environmental protection. As little as 36% of the interviewees claimed receiving direct or indirect benefits from ecotourism, the study finds. It failed to offer any benefits at all to the poorest and most marginal communities. On the contrary, it offered disproportionately larger returns to the remotely located capital invested in the local ecotourism facilities in the Sundarbans, thus defeating the principle behind the mechanism. In the area of conservation, tourism was blamed for increasing pollution and harming the health of the ecosystem by tourists who were considered 'outsiders' and insensitive to the ecology by the locals and conservation agencies alike. [ABSTRACT FROM AUTHOR]

Abstract The ability of mangrove trees to reproduce and disperse in highly dynamic tidal environments is reflected in the contemporary genetic diversity and structure of their populations. Resilience and establishment may occur through either local recruitment (propagule pool model) or over longer distances with mixed origins (migrant pool model), thereby affecting the connectivity between natural populations. Anthropogenic activities such as encroachment and fragmentation or from mitigating reforestation could cause strategy switches and thus the connectivity and genetic structure of populations. In this study, we considered Avicennia officinalis , a dominant component of the Sundarban mangrove forest in Bangladesh to estimate dispersal dynamics over various distances within estuaries. A total of 423 individuals of A. officinalis, distributed over thirteen sites in the Sundarbans were sampled at both large and fine-scaled spatial level, the latter for comparison of natural and dense with fragmented sites. Up to 62 alleles showed a comparable level of allele diversity and gene diversities at both juvenile and adult life stages, assuming overall high levels of outcrossing. Significant inbreeding levels and high kinship values were solely observed at a reforested A. officinalis site. Genetic variables revealed high levels of connectivity between sites at close vicinity, with only a weak structure over larger geographic distances, between natural core Sundarban and coastal edge populations. Kinship coefficients were mostly low though significant up to several kilometers along estuarine branches, thereby suggesting propagule dispersal beyond each site. A fine-scaled analysis of kinship levels estimated for fragmented and natural forest plots along both sides of a river revealed that fragmentation induced higher kinship levels over 25–50 m distance, whereas dense natural populations were composed of less related individuals at shortest distances. A. officinalis populations might stay resilient through a mixture of unrelated propagules, clearly adhering a migrant pool model in natural sites and propagule pool model in fragmented sites. A poor gene diversity of planted trees might jeopardize the sustainability of mangrove plantation practices. Furthermore, high levels of diversity and connectivity indicated that the core Sundarban populations are a relevant source of germplasm in afforestation programmes. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Amitav Ghosh can be seen as the flag bearer of the fearlessness and freedom that the contemporary Indian writer in English embodies. He has become one of the central figures to emerge after the success of Rushdie's Midnight's Children.His 'The Hungry Tide' takes a step further to talk the subaltern experience and raises the national and global awareness about the history of violence inscribed on the Sundarban, throwing into relief the continuing exploitation of the place. [ABSTRACT FROM AUTHOR]

The net primary production (NPP) is a key indicator for assessing the terrestrial carbon pools and fluxes from the atmosphere to biosphere in any given ecosystem. Adequate measurement of the sensitivity and uncertainty of regional and global carbon pools and fluxes in different climatic and anthropogenic regimes is needed to properly investigate the terrestrial carbon balance. Remote sensing light use efficiency (LUE) approaches can be used to quantify the terrestrial NPP accurately. Using LUE models, NPP was calculated for last two decades of an estuarine ecosystem, the Sundarban Biosphere region, India. Results from seven LUE models: Carnegie-Ames-Stanford Approach (CASA), Global Production Efficiency Model (GLO-PEM), Vegetation Photosynthesis Model (VPM), Eddy Covariance-Light Use Efficiency (EC-LUE), MODerate resolution Imaging Spectroradiometer (MOD17), Temperature and Greenness (TG), Greenness and Radiation (GR) models were compared to ascertain model consistency for NPP estimation during the study period 2000–2013. To optimize structural biases in the model accurate parameterization and systematic multi-method assessment were employed. The influence of the input drivers (biophysical, bioclimatic and environmental stress) on model performances was evaluated. Best model performances were observed over cropland, followed by mixed forest and mangrove ecoregion, respectively. Amongst all model, EC-LUE simulated higher NPP at mangrove ecoregion, while the MOD17 model simulated lower NPP in most of the evaluated biomes. In addition, TG and GR models exhibited larger unexplained variances and found statistically significant at mixed forest site. This error was attributed to the absence of environmental stress factors used to drive these model. GLO-PEM and VPM corroborate with NPP prediction among all LUE models. All seven LUE models predict the statistically significant NPP across the biomes and, the poor model performance is attributed to the different parameterization scheme executed for defining the biophysical and stress variables. Biophysical drivers mostly controlled the model performances, followed by environmental stress and bioclimatic drivers, respectively. This analysis is suggesting that the TG and GR model (driven only by the biophysical factors) could be useful in NPP predictions in the regions with no meteorological inputs and real-time eddy covariance flux tower measurement. [ABSTRACT FROM AUTHOR]

This study assessed the status of coastal communities living in a fringe of mangroves forest, Samshernagar in the Indian Sundarban. Demographics of the area were surveyed with questionnaires which also collated their pattern of livelihood related to coastal resources. A total number of respondents were 1404 out of 1560 households. The study identified 14 primary occupations (A) with consideration of both earning and time engagement, along with other two occupations as Secondary (B) and Tertiary (C). Different occupants were made into four broad groups viz., (i) Resource dependent (RD), (ii) Wage earner (WE), (iii) Self resilient (SR) and (iv) Government servant (GS). Resource dependent shared 63.9% among others. A Relative Occupational Priority Index (ROPI) was developed, assessing the degree of strength among primary occupations. Fin fish, shell fish and crab (Af) scored 60.97 numbers, followed by agricultural activities (Aal) with 21.38 numbers. The venture of coastal people for resources collection into forest ecosystem as part of livelihood encountered very often wildlife conflict, including both tiger and crocodile attacks. To reduce resources dependency among coastal inhabitants, management of mangroves ecosystem was undertaken through Focus Group Discussion (FGD) among Forest Development Committees (FDCs) for creating awareness among forest dwellers. Provision of JFM was initiated as an alternative livelihood approach through co-management, though limited success was achieved. [ABSTRACT FROM AUTHOR]

Few studies on hair mercury have been conducted in India despite the fact that India is the world's third largest producer of coal and coal is India's primary energy source. No studies have been conducted in the Indian state of West Bengal which has a coastline with the Bay of Bengal. This study examined the concentration of mercury in hair in two diverse populations in West Bengal, India: Sundarban, a mangrove wetland where fishing is a common occupation, and Calcutta, a megacity and India's oldest functioning port. Individuals from whom scalp hair was collected (N=100) were asked a series of questions on occupation, education, age, smoking and alcohol consumption, and fish consumption. SAS was utilized to generate descriptive statistics including frequency and univariate analyses and to perform regression analyses to determine significant predictors of hair mercury in this population. The mean hair mercury increased across the first three age categories (<21, 21–30, 31–45) and decreased in the fourth category (>45). Hair mercury concentration was significantly higher among residents of Sundarban compared to Calcutta (p=0.0005). In multivariable analysis, location (Sundarban vs. Calcutta) and age were significant predictors of hair mercury concentration (p=0.0120 and p=0.0161, respectively). Average hair mercury concentrations in this study were not particularly elevated. Smoking and alcohol consumption were predictors of hair mercury concentration. The hair mercury in Sundarban residents compared to Calcutta residents may be elevated due to greater consumption of fish and type of fish consumed. [ABSTRACT FROM AUTHOR]

Ornamental fishes are the most popular pet throughout the world and high demand for these fishes has made them an important component of the world fish trade. India contributes a very meager percentage to the world ornamental fish trade; but considering the high ichthyofauna I diversity it has the potential to compete with the world's leading ornamental fish producers in the near future. Sundarban Biosphere Reserve has abundant waterbodies with rich fish diversity. Although some research has been carried out on ichthyofaunal resources of the Sundarban; detailed documentation on freshwater indigenous ornamental ichthyofaunal resources of this region is still not available. To fill this knowledge gap, the present study has been conducted to list the indigenous ornamental ichthyofaunal resources of the Sundarban Biosphere Reserve along with their conservation status and their prospective utilization for improved livelihood of local communities. Eighty four species belonging to 11 orders, 28 families and 59 genera were collected from the study area with species representing the order Cypriniformes dominating the ichthyofauna. Nine species have been listed as Near Threatened in the IUCN Red List of Threatened Species™. Indigenous fish species of the Sundarban having great potential to support domestic as well as the international ornamental fish trade from India in near future. The ornamental fish species would also be able to generate alternate livelihood options for the impecunious communities of the Sundarban. However, serious concern must also be paid to the conservation of these fish species as some of them are under near threatened categories of IUCN Red list. [ABSTRACT FROM AUTHOR]

The Sundarban Biosphere Reserve in West Bengal, India, is part of the largest mangrove forest ecosystem in the world. The reserve is a world heritage site and the last refuge for the endangered Bengal tiger at a crucial time when global climate change threatens their existence. The mangrove ecosystem and wildlife conservation have become the priority for the state government of West Bengal. However, in becoming so, the state government imposes restrictions on catching fish in the core and buffer areas of the biosphere reserve, which intensify fishermen's everyday resource-access struggles in the mangrove forest. This paper examines the conflict between local fishermen and conservation needs, broadening the understanding of human-environment relationships in the Sundarbans region of India. [ABSTRACT FROM AUTHOR]

The study reports the first assessment for the quantification and speciation of butyltins (BTs) in surface marine sediment samples (0-5 cm) from intertidal mudflats of Sundarban mangrove wetland along with the Hugli (Ganges) river basin, eastern coastal part of India. Concentrations of tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) were monitored at 16 stations and present at all study areas, in concentrations in sediments up to 84.2, 26.4 and 48.0 ng g of TBT, DBT and MBT, respectively. Significant correlations were obtained between MBT and DBT ( r = 0.62, p = 0.01) and DBT and TBT ( r = 0.54, p = 0.03). Calculated BT degradation index (BDI) values indicated recent contamination of BTs at 8 stations, and suggested either no degradation of TBT or very recent degradation at a 4 further stations. Additionally, BDI values also indicated no recent inputs of BTs in 4 stations (only MBT present in one of these stations). High concentrations of BTs, particularly TBT, have the potential to induce ecotoxicological impacts based on levels specified in Australian Sediment Quality Guidelines (SQGs). This study indicated that the majority of the analyzed stations were in the highest range of priority, due to high TBT concentrations. [ABSTRACT FROM AUTHOR]

Abstract  A 50 m-long radiocarbon dated core was studied through sediment and pollen analysis to reconstruct the Holocene mangrove and environmental changes at a coastal site Pakhiralaya in the Sundarban Biosphere Reserve in the western Ganga–Brahmaputra Delta, India. This biosphere reserve harbours a diverse mangrove ecosystem and supports a large number of people living in the area. Pollen and stratigraphic data indicate the existence of a brackish water estuarine mangrove swamp forest in this area during the last 9880 cal yr b.p. The development of the mangrove forest is not shown continuously in the Holocene record. Rapid transgression of the sea (9240 cal yr b.p.) halted the development of the mangrove. After about 8420 cal yr b.p. mangrove recolonised the area and persisted until 7560 cal yr b.p. as a result of a balance between the sedimentation and sea level fluctuation. The mangrove disappeared again from the site until 4800 cal yr b.p. because of a high sedimentation rate and possible delta progradation with loss of habitats. The reappearance of mangrove at the study site occurred with a return of a brackish water estuarine environment and the site then gradually became supra tidal during the mid-late Holocene. The continuity of the mangrove development and dynamics was interrupted by the fluctuating sea levels. Climatic fluctuations were viewed as an indirect factor influencing the mangrove ecosystem. [ABSTRACT FROM AUTHOR]

Enterographa bengalensis, a new species is described from the mangrove reserve - Sundarbans Biosphere Reserve, West Bengal, India. It is characterized by the convergent punctiform to lirelliform ascomata, 12-15(-17) septate fusiform ascospores and the presence of psoromic acid. In addition, three species of the genus viz. E. anguinella (Nyl.) Redinger, E. divergens (Müll. Arg.) Redinger and E. multiseptata R. Sant. are also reported for the first time from India. [ABSTRACT FROM AUTHOR]

A new species, Chrysothrix septemseptata, is described from India. It is characterized by 7-septate ascospores, which is unique within the genus. It is currently known only from the Sundarbans Biosphere Reserve, where it grows in mangrove plantations. [ABSTRACT FROM AUTHOR]

The article offers information on the fish feeding bahavior of Rhesus macaque located in several mangrove swamps in Sundarban, India. The author mentions how these macaques adapted to live with human beings in the country. The author considers these monkeys as generalist in terms of feeding behavior, denoting its adaptability in eating fishes.