scholarly journals Metal Distribution and Short-Time Variability in Recent Sediments from the Ganges River towards the Bay of Bengal (India)

Geosciences ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 260 ◽  
Author(s):  
Estefanía Bonnail ◽  
Rocío Antón-Martín ◽  
Inmaculada Riba ◽  
T. Ángel DelValls
Keyword(s):  
Bay Of Bengal ◽  
Drainage Basin ◽  
Anthropogenic Activities ◽  
Industrial Effluents ◽  
Vertical Gradient ◽  
Element Distribution ◽  
Time Variability ◽  
Ganges River ◽  
Monsoon Period ◽  
The Ganges

The Ganges River receives inputs from highly populated cities of India (New Delhi, Calcutta, among others) and a strong influence of anthropogenic activities until reaching the Bay of Bengal. It is a seasonal river with 80% of discharges occurring between July and October during monsoon. The land-based activities next to the shore lead to discharges of untreated domestic and industrial effluents, inputs of agricultural chemicals, discharges of organic matter (cremations), and discharges of chemicals from aquaculture farms. In spite of the UNESCO declaring Human Patrimony the National Park Sundarbans, located in the delta, contamination has increased over time and it dramatically intensifies during the monsoon period due to the flooding of the drainage basin. Vertical element distribution (Cd, Co, Hg, Ni, Pb, and Zn) was studied in sediments collected in different stations towards the Hügli Estuary. Results determined no vertical gradient associated with the analyzed sediment samples, which informs about severe sediment dynamic in the area that probably relates to tidal hydrodynamics and seasonal variation floods. The multivariate analysis results showed different associations among metals and in some cases between some of them (Co, Zn, Pb, and Cu) and the organic carbon. These allow the identification of different geochemical processes in the area and their relationship with the sources of contamination such as discharge of domestic and industrial effluents and diffuse sources enhanced by the monsoons. Also, an environmental risk value was given to the studied area by comparing the analyzed concentrations to quality guidelines adopted in other countries. It showed an estimated risk associated with the concentration of the metal Cu measured in the area of Kadwip.

scholarly journals A Note on “Metal Distribution and Short-Time Variability in Recent Sediments from the Ganges River towards the Bay of Bengal (India)” by Bonnail et al. (2019)

Geosciences ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 61
Author(s):  
Mohammad Ayaz Alam
Keyword(s):  
Anthropogenic Activities ◽  
River Sediments ◽  
Time Variability ◽  
New Delhi ◽  
Ganges River ◽  
National Capital Region ◽  
National Capital ◽  
Recent Sediments ◽  
Short Time ◽  
The Ganges

A careful reading of Bonnail et al. (2019)’s work points out some issues in the description of the Ganges River, e.g., describing it in a way that gives impression to the readers unfamiliar with the Indian rivers that it flows by the national capital New Delhi, after reading “it receives inputs from highly populated cities of India, including New Delhi and …”. However, as a matter of fact, it is not the Ganges, but the Yamuna River, a tributary of the Ganges, that passes through the National Capital Region of Delhi. Moreover, authors identify the studied river as the Ganges, whereas it is one of the distributaries of the Ganges called Hooghly (anglicized version of its local name Hugli). They have referred to the seasonality of the studied river; however, the flow of the studied (Hooghly) river is controlled by a barrage on the Ganges River. Moreover, Hooghly River receives input from its own tributaries; viz., Mayurakshi and Damodar, flowing through highly mineralized and coaliferous areas of Jharkhand state of India. Bonnail et al. (2019) have attributed the contamination of the river sediments to anthropogenic activities alone, by not evaluating likely natural sources. A correction factor for the underestimated total organic carbon (TOC) content obtained using Walkley-Black method should have been applied before using TOC values for factor analysis to overcome the underestimation issue with this method. This work intends to serve as a compendium, rather than a critique, to otherwise commendable work by Bonnail et al. (2019).

scholarly journals Characterization of artisanal fisheries in Nepal and potential implications for the conservation and management of Ganges River Dolphin (Platanista gangetica gangetica)

2015 ◽  
Author(s):  
Shambhu Paudel ◽  
Juan C Levesque ◽  
Camilo Saavedra ◽  
Cristina Pita ◽  
Prabhat Pal
Keyword(s):  
Anthropogenic Activities ◽  
Fishing Effort ◽  
Main Channel ◽  
Artisanal Fisheries ◽  
Ganges River ◽  
River Systems ◽  
River Dolphin ◽  
Main River ◽  
Local Species ◽  
The Ganges

The Ganges River dolphin (Platanista gangetica gangetica) (GRD) is classified as one of the most endangered of all cetaceans in the world and the second scarcest freshwater cetacean. The population is estimated to be less than 2,000 individuals. In Nepal’s Narayani, Sapta Koshi, and Karnali river systems, survival of GRD continues to be threatened by various anthropogenic activities, such as dam construction and interactions with artisanal fisheries. A basic description of the geographic scope, economics, and types of gear used in these fisheries would help managers understand the fishery-dolphin interaction conflict and assist with developing potential solutions to reduce interactions between GRD and local fisheries in Nepal. The main purpose of the study was to collect fishery and socio-economic information by conducting interviews with local fishermen in the Narayani, Sapta Koshi, and Karnali river systems. Based on interviews (n = 163), 79 percent of Nepalese fishermen indicated fishing for local species (e.g., mullet [Rhinomugil corsula] or siloroid catfish [Bagarius bagarius]) was their primary form of income. Fishermen reported fishing effort was greater in summer than winter; greatest in the afternoon (1430 hrs ± 0.27) and during low water level conditions; and gear was set 4.8 ± 0.2 days/week. Fishermen reported using eight different types of monofilament nets (gillnets and cast nets). Sixty percent used gillnets less than 10 m long, and less than one third preferred gillnets between 10 and 100 m long; a few used gillnets longer than 100 m. Fishermen usually set their gear close to their village, and about 50 percent preferred to fish in tributaries followed by the main channel behind sandbars and islands, and the main channel near a bank. Fishermen reported seeing more GRD in the main river stem in winter. In summer, fishermen spotted more GRD in tributaries. Most fishermen told us they believed education, awareness, and changing occupations were important for GRD conservation, but they indicated that occupational options were currently limited in Nepal. Nepalese fishermen acknowledged that fisheries posed a risk to GRD, but they believed water pollution, and dam/irrigation development were the greatest threats.

scholarly journals Stable Strontium Isotopic Compositions of River Water, Groundwater and Sediments From the Ganges–Brahmaputra–Meghna River System in Bangladesh

2021 ◽  
Vol 9 ◽  
Author(s):  
Toshihiro Yoshimura ◽  
Shigeyuki Wakaki ◽  
Hodaka Kawahata ◽  
H. M. Zakir Hossain ◽  
Takuya Manaka ◽  
...  
Keyword(s):  
River Water ◽  
Chemical Weathering ◽  
Drainage Basin ◽  
Dissolution Kinetics ◽  
River System ◽  
Ganges River ◽  
Brahmaputra River ◽  
Terrestrial Water ◽  
Stable Strontium ◽  
The Ganges

The Sr isotopic composition of rivers and groundwaters in the Bengal Plain is a major contributor to the global oceanic Sr inventory. The stable strontium isotope ratios (δ88Sr) provide a new tool to identify chemical weathering reactions in terrestrial water. In this study, we investigated the spatiotemporal variations of δ88Sr in samples of river water, bedload sediment, and groundwater collected from the Ganges–Brahmaputra–Meghna drainage basin in Bangladesh, which is known to strongly influence the 87Sr/86Sr ratio in seawater. The average δ88Sr values of waters of the Ganges, Brahmaputra, and Meghna rivers were 0.269, 0.316, and 0.278‰, respectively. Our data showed little difference between seasons of high and low discharge. The δ88Sr values measured in sequential leaching fractions of sediments varied from –0.258 to 0.516‰ and were highest in the silicate fraction, followed in turn by the carbonate fraction and the exchangeable fraction. Both 87Sr/86Sr and δ88Sr of these waters are primarily controlled by the inputs of Sr in weathering products from the Bengal Plain and Sr from the Himalayan rivers (Ganges and Brahmaputra). Values of δ88Sr and Sr/Ca were higher in the Brahmaputra River than in the Ganges River, a difference we attribute to greater input from silicate weathering. The variations of δ88Sr and 87Sr/86Sr were greater in groundwater than in river waters. Mineral sorting effects and dissolution kinetics can account for the large scatter in 87Sr/86Sr and δ88Sr values. The depth profile of δ88Sr showed wide variation at shallow depths and convergence to a narrow range of about 0.31‰ at depths greater than 70 m, which reflects more complete equilibration of chemical interactions between groundwater and ambient sediments owing to the longer residence time of deeper groundwater. We found that δ88Sr values in the groundwater of Bangladesh were almost identical to those of river water from the lower Meghna River downstream of its confluence with the Ganges–Brahmaputra river system, thus confirming that the δ88Sr composition of the groundwater discharge to the Bay of Bengal is very similar to that of the river discharge.

scholarly journals Status of the Ganges river dolphin or shushuk Platanista gangetica in Kaptai Lake and the southern rivers of Bangladesh

Oryx ◽  
2001 ◽  
Vol 35 (1) ◽  
pp. 61-72 ◽  
Author(s):  
Brian D. Smith ◽  
Benazir Ahmed ◽  
Muhammad Edrise Ali ◽  
Gill Braulik
Keyword(s):  
Bay Of Bengal ◽  
Protected Area ◽  
Encounter Rate ◽  
Ganges River ◽  
Marine Waters ◽  
Conservation Measure ◽  
Freshwater Plumes ◽  
River Mouths ◽  
The Ganges ◽  
Persistent Contaminants

AbstractSurveys for shushuks Platanista gangetica were conducted during January to April 1999 in Kaptai Lake and the southern rivers of Bangladesh. A population of at least 125 dolphins was recorded in the Karnaphuli and Sangu rivers and connecting canal. The overall encounter rate was 0.76 dolphins per km. Density was highest in the lower reaches of the Sangu, where we recorded 1.36 dolphins per km. These rates are fairly high when compared with other areas of shushuk distribution. Dolphin movements in the Sikalbaha–Chandkhali Canal were consistent with it being used as a corridor for migration and dispersal between the Karnaphuli and Sangu. Shushuks were also sighted in marine waters of the Karnaphuli and Sangu river mouths, adding credibility to the hypothesis that dolphins move along the coast between the Ganges–Brahmaputra–Meghna and Karnaphuli–Sangu systems, perhaps during the monsoon when freshwater plumes extend into the Bay of Bengal. No dolphins were nobserved in Kaptai Lake, a dam-created reservoir of the upper Karnaphuli, despite reports of occasional sightings by local fishermen. No shushuks were observed in the Bagkhali and Matamuhuri rivers, possibly because of seasonal-closure dams present near the mouths of both rivers. The main threats to dolphin survival in the Karnaphuli-Sangu system are probably accidental entanglement in monofilament gillnets, bioaccumulation of persistent contaminants and possibly collisions with motorized vessels and a decline in prey as a result of over fishing. The most significant conservation measure that could be taken would be to establish a protected area for dolphins in the Sangu River below the Dohazari Bridge.

scholarly journals Message in a bottle: Open source technology to track the movement of plastic pollution

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0242459
Author(s):  
Emily M. Duncan ◽  
Alasdair Davies ◽  
Amy Brooks ◽  
Gawsia Wahidunnessa Chowdhury ◽  
Brendan J. Godley ◽  
...  
Keyword(s):  
Open Source ◽  
Bay Of Bengal ◽  
Animal Movement ◽  
Public Awareness ◽  
River System ◽  
Educational Outreach ◽  
Source Tracking ◽  
Ganges River ◽  
Plastic Pollution ◽  
The Ganges

Rivers worldwide are now acting as major transport pathways for plastic pollution and discharge large quantities of waste into the ocean. Previous oceanographic modelling and current drifter data have been used to predict the movement and accumulation of plastic pollution in the marine environment, but our understanding of the transport and fate through riparian systems is still largely unknown. Here we undertook a proof of concept study by applying open source tracking technology (both GPS (Global Positing System) cellular networks and satellite technology), which have been successfully used in many animal movement studies, to track the movements of individual plastic litter items (500 ml PET (polyethylene terephthalate) drinks bottles) through the Ganges River system (known as the Ganga in India and the Padma and Meghna in Bangladesh, hereafter known as the Ganges) and the Bay of Bengal. Deployed tags were successfully tracked through the Ganges river system and into the Bay of Bengal marine system. The “bottle tags” were designed and built (e.g. shape, size, buoyancy) to replicate true movement patterns of a plastic bottle. The maximum distance tracked to date is 2845 km over a period of 94 days. We discuss lessons learnt from the development of these plastic litter tags, and outline how the potential widespread use of this open source technology has the ability to significantly increase understanding of the location of accumulation areas and the timing of large inputs of plastic pollution into the aquatic system. Furthermore, “bottle tags” may act as a powerful tool for stimulating social behaviour change, informing science-based policy, and as valuable educational outreach tools for public awareness.

scholarly journals Characterization of the artisanal fishing communities in Nepal and potential implications for the conservation and management of Ganges River Dolphin (Platanista gangetica gangetica)

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1563 ◽  
Author(s):  
Shambhu Paudel ◽  
Juan C. Levesque ◽  
Camilo Saavedra ◽  
Cristina Pita ◽  
Prabhat Pal
Keyword(s):  
Anthropogenic Activities ◽  
Fishing Effort ◽  
Fishing Communities ◽  
Ganges River ◽  
Artisanal Fishing ◽  
River Dolphin ◽  
New Information ◽  
The Ganges ◽  
Primary Form

The Ganges River dolphin (Platanista gangetica gangetica) (GRD) is classified as one of the most endangered of all cetaceans in the world and the second scarcest freshwater cetacean. The population is estimated to be less than 2,000 individuals. In Nepal’s Narayani, Sapta Koshi, and Karnali river systems, survival of GRD continues to be threatened by various anthropogenic activities, such as dam construction and interactions with artisanal fisheries. A basic description of the geographic scope, economics, and types of gear used in these fisheries would help managers understand the fishery-dolphin interaction conflict and assist with developing potential solutions. The main goal was to provide new information on the artisanal fishing communities in Nepal. The specific objectives were to identify, compile, and investigate the demographics, economics, fishing characteristics, and perception of fishermen about GRD conservation in the Narayani, Sapta Koshi, and Karnali rivers so conservation managers can develop and implement a potential solution to the GRD-fishery interaction problem in Nepal. Based on 169 interviews, 79% of Nepalese fishermen indicated fishing was their primary form of income. Fishermen reported fishing effort was greater in summer than winter; greatest in the afternoon (14:30 hrs ± 0:27) and during low water level conditions; and gear was set 4.8 ± 0.2 days/week. Fishermen reported using eight different types of monofilament nets (gillnets and cast nets). Sixty percent used gillnets less than 10 m long, and nearly 30% preferred gillnets between 10 and 100 m long; a few used gillnets longer than 100 m. Most fishermen reported they believed education, awareness, and changing occupations were important for GRD conservation, but they indicated that alternative occupational options were currently limited in Nepal. Nepalese fishermen acknowledged that fisheries posed a risk to GRD, but they believed water pollution, and dam/irrigation developments were the greatest threats.

scholarly journals Coastline Dynamics and Raising Landform: A Geo-informatics Based Study on the Bay of Bengal, Bangladesh

2018 ◽  
Vol 50 (1) ◽  
pp. 41
Author(s):  
Nur Hussain ◽  
Ebadullah Khan
Keyword(s):  
Bay Of Bengal ◽  
Strong Wind ◽  
Monsoon Period ◽  
Coastal Planning ◽  
Change Dynamics ◽  
Remote Sensing Technology ◽  
Coastline Change ◽  
Sensing Technology ◽  
Major River ◽  
The Ganges

The southern part of Bangladesh is bounded by the Bay of Bengal. Three major river systems such as; Brahmaputra-Jamuna, Ganges-Padma and Surma-Kusiara have been developed the Ganges-Brahmaputra-Meghna (GBM) floodplain, this are 80% area of Bangladesh. These rivers carry huge sediments from upper Himalayan region during at monsoon period. On the contrary, as the costal part of Bangladesh is open to the sea, so high wave actions, strong wind flow, tidal actions are prevailing here. Consequently, coastline of this part is unstable and dynamic. Coastline change dynamics is significant for disaster management, coastal planning and environmental management. For the delineation of coastline identification, Rennell’s map (1776), Landsat MSS (1976) and Landsat OLI (2016) images have been interpreted using the tools of Remote Sensing Technology and Geographic Information System (GIS) of Geo-informatics. During 240 years from 1776 to 2016 about 3892 km2 landform have been raised in coastal area of Bangladesh.

scholarly journals Characterization of artisanal fisheries in Nepal and potential implications for the conservation and management of Ganges River Dolphin (Platanista gangetica gangetica)

2015 ◽  
Author(s):  
Shambhu Paudel ◽  
Juan C Levesque ◽  
Camilo Saavedra ◽  
Cristina Pita ◽  
Prabhat Pal
Keyword(s):  
Anthropogenic Activities ◽  
Fishing Effort ◽  
Main Channel ◽  
Artisanal Fisheries ◽  
Ganges River ◽  
River Systems ◽  
River Dolphin ◽  
Main River ◽  
Local Species ◽  
The Ganges

The Ganges River dolphin (Platanista gangetica gangetica) (GRD) is classified as one of the most endangered of all cetaceans in the world and the second scarcest freshwater cetacean. The population is estimated to be less than 2,000 individuals. In Nepal’s Narayani, Sapta Koshi, and Karnali river systems, survival of GRD continues to be threatened by various anthropogenic activities, such as dam construction and interactions with artisanal fisheries. A basic description of the geographic scope, economics, and types of gear used in these fisheries would help managers understand the fishery-dolphin interaction conflict and assist with developing potential solutions to reduce interactions between GRD and local fisheries in Nepal. The main purpose of the study was to collect fishery and socio-economic information by conducting interviews with local fishermen in the Narayani, Sapta Koshi, and Karnali river systems. Based on interviews (n = 163), 79 percent of Nepalese fishermen indicated fishing for local species (e.g., mullet [Rhinomugil corsula] or siloroid catfish [Bagarius bagarius]) was their primary form of income. Fishermen reported fishing effort was greater in summer than winter; greatest in the afternoon (1430 hrs ± 0.27) and during low water level conditions; and gear was set 4.8 ± 0.2 days/week. Fishermen reported using eight different types of monofilament nets (gillnets and cast nets). Sixty percent used gillnets less than 10 m long, and less than one third preferred gillnets between 10 and 100 m long; a few used gillnets longer than 100 m. Fishermen usually set their gear close to their village, and about 50 percent preferred to fish in tributaries followed by the main channel behind sandbars and islands, and the main channel near a bank. Fishermen reported seeing more GRD in the main river stem in winter. In summer, fishermen spotted more GRD in tributaries. Most fishermen told us they believed education, awareness, and changing occupations were important for GRD conservation, but they indicated that occupational options were currently limited in Nepal. Nepalese fishermen acknowledged that fisheries posed a risk to GRD, but they believed water pollution, and dam/irrigation development were the greatest threats.

Hydro-geochemical properties with respect to landuse in the southernmost river of Kerala

2018 ◽  
Vol 6 (1) ◽  
Author(s):  
Badusha M. ◽  
Santhosh S
Keyword(s):  
Organic Carbon ◽  
Drainage Basin ◽  
Anthropogenic Activities ◽  
Oxygen Demand ◽  
Ion Concentration ◽  
Total Hardness ◽  
Hydrogen Ion Concentration ◽  
Geochemical Properties ◽  
Quality Of Water

The hydro geochemical features of Neyyar River for a period of one year from May 2015 to April 2016 were analyzed. Six sampling sites were fixed considering physiography and present landuse pattern of the river basin. The residents in the drainage basin are primarily responsible for framing a better landuse and thereby maintain a good water and sediment regime. Geospatial pattern of the present landuse of the study area indicated that the sustainability of this river ecosystem is in danger due to unscientific landuse practices, which is reflected in the river quality as well. The parameters such as hydrogen ion concentration, electrical conductivity, chloride, Biological Oxygen Demand, total hardness and sulphate of river water and Organic Carbon of river bed sediments were analyzed in this study. The overall analysis shows that the highland areas are characterized by better quality of water together with low organic carbon, which is mainly due to better landuse and minimal reclamation. The midland and lowland areas are characterized by poor quality of water with high organic carbon, which is due to high anthropogenic activities and maximum pollutants associated with the region together with the alteration in landuse from a traditional eco-friendly pattern to a severely polluted current pattern.

Chemical Composition and Metal Speciation in Porewaters from the Upper Qu’Appelle River Basin, Saskatchewan

1993 ◽  
Vol 28 (1) ◽  
pp. 83-110 ◽  
Author(s):  
Richard E. Farrell ◽  
Jae E. Yang ◽  
P. Ming Huang ◽  
Wen K. Liaw
Keyword(s):  
Amino Acids ◽  
Trace Metal ◽  
River Basin ◽  
Drainage Basin ◽  
Metal Speciation ◽  
Anthropogenic Activities ◽  
High Concentration ◽  
Metal Concentrations ◽  
Carbonate Equilibria ◽  
The Impact

Abstract Porewater samples from the upper Qu’Appelle River basin in Saskatchewan, Canada, were analyzed to obtain metal, inorganic ligand and amino add profiles. These data were used to compute the aqueous speciation of the metals in each porewater using the computer program GEOCHEM-PC. The porewaters were classified as slightly to moderately saline. Metal concentrations reflected both the geology of the drainage basin and the impact of anthropogenic activities. Whereas K and Na were present almost entirely as the free aquo ions, carbonate equilibria dominated the speciation of Ca. Mg and Mn (the predominant metal ligand species were of the type MCO3 (s). MCO30. and MHCO3+). Trace metal concentrations were generally within the ranges reported for non-polluted freshwater systems. Whereas the speciation of the trace metals Cr(III) and Co(II) was dominated by carbonate equilibria, Hg(II)-, Zn(II)- and Fe(II)-speciation was dominated by hydroxy-metal complexes of the type M(OH)+ and M(OH)2°. The speciation of Fe(III) was dominated by Fe(OH)3 (s). In porewaters with high chloride concentrations (> 2 mM), however, significant amounts of Hg(II) were bound as HgCl20 and HgClOH0. The aqueous speciation of Al was dominated by Al(OH)4− and Al2Si2O4(OH)6 (s). Total concentrations of dissolved free amino acids varied from 15.21 to 25.17 umole L−1. The most important metal scavenging amino acids were histidine (due to high stability constants for the metal-histidine complexes) and tryptophan (due to its relatively high concentration in the porewaters. i.e., 5.96 to 7.73 umole L−1). Secondary concentrations of various trace metal-amino add complexes were computed for all the porewaters, but metal-amino acid complexes dominated the speciation of Cu(II) in all the porewaters and Ni(II) in two of the porewaters.

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