Padma River Research Articles

Existence of panmictic Hilsa shad (Tenualosa ilisha) populations from two large river ecosystems in Bangladesh revealed by mitochondrial control region

The present study was undertaken to estimate genetic diversity and reveal population structure of Hilsa shad (Tenualosa ilisha) from two large river ecosystems, the Padma and Meghna of Bangladesh using mitochondrial control region (D-loop region). Fin tissue samples of 60 individuals were collected from the Padma (ChapaiNawabgonj) and Meghna River (Chandpur). DNA was extracted and D-loopof mtDNA was amplified, purified and sequenced. A total of 35 Sequences (15 Sequences from the Padma and 20 Sequences from the Meghna population) were analyzed and 14 haplotypes were detected. Total16 polymorphic sites were identified that included11 singleton sites and 5 parsimony informative sites. These populations showed high haplotype diversity (h) (0.863 in the Meghna and 0.901in the Padma population). We found low nucleotide diversity (Pi) within each population, 0.0058±0.0039 in the Padma to 0.0063±0.004 in the Meghna population. The shared haplotypes among the two populations were identified as 28.57%, and the rest 71.43% were private haplotypes. Estimate of genetic differentiations (Fst) suggest that the Meghna population of Hilsa was closely related to the Padma population (Fst= 0.058, P=0.07). The TCS genealogy showed three main haplotypes separated by three mutational steps and hap_10 might be the most ancestral haplotype by its internal position in the network. All results suggest panmixia in T. ilisha populations between the Meghna and Padma river populations and thus similar management plan could be useful for these two river Hilsa fishery in Bangladesh.

Wildlife diversity of the Padma River islands, Rajshahi, Bangladesh with special notes on the operation of sand snake (Psammophis condanarus) (Merrem, 1820) (Reptilia: Squamata: Lamprophiidae)

Wildlife diversity of the Padma River islands, Rajshahi, Bangladesh with special notes on the operation of sand snake (Psammophis condanarus) (Merrem, 1820) (Reptilia: Squamata: Lamprophiidae)

Application of double lifting method for river water irrigation in the water stressed Barind Tract of northwest Bangladesh

Groundwater has become the prime source of drinking and irrigation use in drought-prone Barind Tract (BT) of Bangladesh as the surface water sources are minimal. Continuous groundwater withdrawals for irrigation, drinking, domestics, industries and other uses deplete groundwater levels (GWL). So, the study aims to compute the quantity of river water extracted for irrigation by double lifting and rubber dam irrigation systems of Barind Multipurpose Development Authority (BMDA) in BT area and evaluate their impacts on reducing groundwater exploitation. To carry out the study, bore log lithology, rainfall, GWL, and water irrigation data have been collected from BMDA and field investigation and analyzed the Groundwater depletion due to over-extraction than the potential recharge, lower rainfall than the national average, and thick top clay that limits the natural recharge. Lifted water by the pumps of 11 pontoons placed on the river Padma (Ganges), Mohanonda, and Atrai can reduce 7.08% of groundwater extraction for irrigation in the study area. Groundwater exploitation for Puthia Upazila can be reduced by 10.11% with conserved water upstream of the rubber dam constructed in the Barnai river. Also, a continuous rise in GWL was observed due to storing of river water at a 4 km long section by the rubber dam.

Assessing the Impact of the Farakka Barrage on Hydrological Alteration in the Padma River with Future Insight

Climate change and human interventions (e.g., massive barrages, dams, sand mining, and sluice gates) in the Ganga–Padma River (India and Bangladesh) have escalated in recent decades, disrupting the natural flow regime and habitat. This study employed innovative trend analysis (ITA), range of variability approach (RVA), and continuous wavelet analysis (CWA) to quantify the past to future hydrological change in the river because of the building of the Farakka Barrage (FB). We also forecast flow regimes using unique hybrid machine learning techniques based on particle swarm optimization (PSO). The ITA findings revealed that the average discharge trended substantially negatively throughout the dry season (January–May). However, the RVA analysis showed that average discharge was lower than environmental flows. The CWA indicated that the FB has a significant influence on the periodicity of the streamflow regime. PSO-Reduced Error Pruning Tree (REPTree) was the best fit for average discharge prediction (RMSE = 0.14), PSO-random forest (RF) was the best match for maximum discharge (RMSE = 0.3), and PSO-M5P (RMSE = 0.18) was better for the lowest discharge prediction. Furthermore, the basin’s discharge has reduced over time, concerning the riparian environment. This research describes the measurement of hydrological change and forecasts the discharge for upcoming days, which might be valuable in developing sustainable water resource management plans in this location.

Classification of Geomorphic Units and Their Relevance for Nutrient Retention or Export of a Large Lowland Padma River, Bangladesh: A NDVI Based Approach

Geomorphic classification of large rivers identifies morphological patterns, as a foundation for estimating biogeochemical and ecological processes. In order to support the modelling of in-channel nutrient retention or export, the classification of geomorphic units (GUs) was done in the Padma River, Bangladesh, a large and geomorphically-complex lowland river. GUs were classified using the normalized difference vegetation index (NDVI) four times over a year, so as to cover the seasonal variation of water flows. GUs were categorized as primary and secondary channels (C & S); longitudinal bar (L); transverse bar (T); side bar (SB); unvegetated bank (EK); dry channel (ED); island (VI); and water depression (WD). All types of GUs were observed over the four distinct annual seasons, except ED, which was absent during the high flow, monsoon season. Seasonal variation of the surface area of GUs and discharge showed an inverse relation between discharge and exposed surface areas of VI, L, T, and SB. Nutrients mainly enter the river system through water and sediments, and during monsoon, the maximum portion of emergent GUs were submerged. Based on the assumption that nutrient retention is enhanced in the seasonally inundated portions of GUs, nutrient retention-/export-relevant geomorphic units (NREGUs) were identified. Seasonal variation in the area of NREGUs was similar to that of GUs. The mean NDVI values of the main identified NREGUs were different. The variation of NDVI values among seasons in these NREGUs resulted from changes of vegetation cover and type. The variation also occurred due to alteration of the surface area of GUs in different seasons. The changes of vegetation cover indicated by NDVI values across seasons are likely important drivers for biogeochemical and ecological processes.

Application of silicon nanoparticles extracted from the Padma river sand of Bangladesh as dopant in metal oxide semiconducting thin films

Fabrication of silicon nanoparticles (Si-NPs) from the Padma river sand of Bangladesh by a low-temperature, low-cost, and zero-CO2 emitting process and its application as a dopant in CuO and ZnO have been presented in this article with a motivation to see the influence of locally fabricated Si-NPs on the optoelectronic properties of CuO and ZnO thin films. The sand (SiO2) was reduced using a modified aluminothermic reaction, and leaching with hydrochloric acid (HCL) was used to purify the reaction product to extract > 98% pure Si. After cleaning and drying, the obtained Si powder was ultrasonicated for crushing them into tiny particles of 60–180 nm. The ultrasonicated silicon was further treated with a solution of hydrofluoric acid (HF) and 2-propanol for the etching of the native oxide and passivating the dangling bond with hydrogen (H). Thereafter, highly promising photoactive materials CuO and ZnO were doped with the extracted Si-NPs. Finally, Si-NPs doped CuO and ZnO thin films were deposited on a cleaned glass substrate by spin-coating. X-Ray Diffraction (XRD) confirmed the amorphous nature of Si particles. Dynamic Light Scattering (DLS) demonstrates the size distribution of Si-NPs of ~120 nm for 180 minutes of sonication time. DLS results refer that the higher sonication time offers a lower particle size of Si with controlled rate. The addition of Si-NPs nanoparticles tailors the energy band alignment at the metal oxide/NP interface which provides efficient charge carrier transport and enhanced optical absorption (~20%) as revealed by UV-Vis Spectroscopy. Experimental results indicate that the extracted Si-NPs can be efficiently used in thin-film based optical and electronic devices.

The Low Flow Assessment of Padma River in Bangladesh

Low flow or Environmental Flow (EF) assessment is vital to ensure the river and ecosystem remain healthy. Both natural and human interventions might alter a river. Therefore, this study presents EF requirements of the famous Hilsa breeding center in the Padma River, Bangladesh, by applying the Hydrologic Engineering Centers River Analysis System (HEC-RAS) for discharge and water surface levels simulations at different stations. The frequency analysis of 20 years of historical data, spanning 2000-2019, used the Log-Pearson Type III (LP-III) distribution method, while the one-dimensional unsteady flow simulation was performed for the last 10 years (i.e., 2012-2019). Subsequently, the HEC-RAS simulated water level values reasonably correlated with the field observations at four stations, namely Baruria Transit, Mawa, Tarpasha, Sureswar, with Coefficient of determination R2=0.86, 0.83, 0.92, and 0.74, alongside simulated minimum water surface levels of 1.57 m, 0.37 m, 0.30 m, and 0.27 m, respectively. Also, the Baruria Transit and Mawa had simulated flows that reasonably correlated with the field observations at R2=0.70 and 0.61, with a simulated minimum flow of 3849.51 m3/s and 3789.14 m3/s, respectively. The minimum flow according to the frequency analysis was 4017 m3/s, 3685 m3/s, 3449 m3/s, 3229 m3/s, and 3113 m3/s at Baruria Transit and 3304 m3/s, 2781 m3/s, 2438 m3/s, 2141 m3/s, 1992 m3/s at Mawa station in 5, 10, 20, 50 and 100 years return periods, respectively. This study overlooked to report the ongoing investigations into the water quality issues. Thus, this study is expected to guide the required EF quantity towards a healthy Hilsha fish habitat and surface water source for drinking purposes in this studied river. The stated method is also applicable to other similar rivers around the world.

Role of declining discharge and water pollution on habitat suitability of fish community in the Mathabhanga-Churni River, India

The present study examines the habitat suitability of three selected reaches of the Mathabhanga-Churni River in the wake of the declining river regime and escalating river water pollution. The study portrays the habitat degradation through the lens of the habitat suitability index (HSI) model based on four water quality (turbidity, pH, dissolved oxygen, and water temperature), three reproduction (pool velocity, riffle velocity, and riffle depth), and two food and cover (percentage vegetation cover and percentage pool) variables. Among the water quality variables, depletion in DO (0.4 mg/L) has become the most significant factor for fish habitat degradation. Reach-specific study of HSI reveals high habitat degradation for reach1 (RE1) and reach 2 (RE2) compared to reach 3 (RE3). The seasonality in HSI has also been reflected for all the study reaches. The value of HSI at RE1 depicts that 97.67% of samples of pre-monsoon season belong to the poor habitat category. Moreover, the study of fish species also reveals that the diversity and productivity have declined at a faster rate for RE1 and RE2 compared to RE3. For example, 29, 28, and 21 fish species have disappeared from RE1, RE2, and RE3 respectively since 1983. This typical habitat degradation is induced by lowering of discharge due to longitudinal disconnection of the Mathabhanga-Churni River from the Padma River due to the eastward tilting of the Bengal delta. Moreover, anthropogenic pollution such as discharge of industrial effluents, mixing of municipal sewage, pollutants from agricultural runoff are found to exacerbate habitat degradation. Finally, the study indicates few ways to restore the degraded fish habitat of the river.

A Study on the Flux of Total Suspended Matter in the Padma River in Bangladesh Based on Remote-Sensing Data

The flux of total suspended matter (TSM), FTSM, output by several large rivers in Asia, has been in decline due to human activities. As the estuary of the Ganges–Brahmaputra River, the Padma River transports a significant amount of suspended matter (SM) to the Bay of Bengal each year. In this study, the TSM concentration (CTSM) and FTSM in the Padma River in the period 1991–2019 were calculated based on the data acquired by the Landsat series satellites and an empirical TSM algorithm model for large, high-turbidity rivers. The results showed that the maximum and minimum FTSM values (318 ± 62 and 73 ± 29 mt, respectively) in the Padma River occurred in 2011 and 2015, respectively. On average, FTSM in the Padma River decreased at an annual rate of 3.3 mt (p < 0.01). The impact of human activities on CTSM contributed more significantly to the changes in FTSM (R = 0.76) than natural factors (R = 0.44). Due to a lack of water conservancy facilities within the river basin, changes in the water and soil retention capacity due to the changes in vegetation coverage were an important human factor (R = −0.79).

Fish culture in net cages improves the livelihood of Charland population: a case study from Padma (Ganga) River, Munshiganj, Bangladesh

Char dwellers are considered poorer than the mainland population. A constant threat of riverbank failure, flooding, and seasonal cyclone, combined with lack of physical infrastructures, and employment opportunities in the Chars, makes a vulnerable, difficult, and fragile life. The aim of the present work was an initiative to improve the livelihood of Char dwellers through fish culture in the net cages. A focus group survey was conducted on Char dwellers to know about the livelihood conditions. Quantitative and qualitative analysis of plankton was performed to know the productivity of the Padma River. In the study area, there was an average of 5 household members in each family of the Charland dwellers, and the average sex ratio of males and females was 56.67% and 43.33%, respectively. The age group of below 15 to 60 years and their religion ratio of Muslim and Hindu was 45% and 55%. The total number of identified genera of phytoplankton was 41, and the total number of zooplankton genera was 20 in the Padma River. Tilapia (Oreochromis niloticus) was cultured in the net cages providing three different feeds i.e. natural feed, kitchen waste (leftover rice), and rice bran. The final weights of the experimental tilapia were 314.8 ± 24.3 g after 5 months of feeding natural food, 321.4 ± 22.8 g after 5 months of feeding natural food with kitchen waste, and 324.8 ± 29.5 g after 5 months of feeding natural food with rice bran. Considering the plankton populations and water quality parameters, the Padma River near the Charland of Munshiganj was productive for fish farming. We found the results of Genetically Improved Farmed Tilapia (GIFT) farming in net cages near the river of Char, which were almost the same (has no significant difference among the diets) by providing low-cost supplementary feed and without supplementary feed. Therefore, the result indicates that Char dwellers can culture fishes in net cages to have the fish in their daily meals and can earn extra income from selling the fish to improve their livelihood. Moreover, applied research and interdisciplinary adaptive policy framework are requisite for the Charland livelihoods sustainability in the Padma River, Munshiganj, Bangladesh. Asian J. Med. Biol. Res. 2021, 7 (2), 174-181

The status of NORMs in natural environment adjacent to the Rooppur nuclear power plant of Bangladesh

The Rooppur Nuclear Power Plant (RNPP), the first nuclear power plant in Bangladesh with a capacity of 2.4 GWe, is under construction on the bank of the river Padma, at Rooppur in Bangladesh. Measurement of background radioactivity in the natural environment adjacent to RNPP finds great importance for future perspectives. Soil and sediment samples collected from upstream and downstream positions of the Padma River (adjacent to RNPP) were collected and analyzed by HPGe gamma-ray spectrometry for primordial radionuclides. The average activity concentrations (in Bqkg−1) of 226Ra, 232Th and 40K radionuclides in soil samples were found to be 44.99 ± 3.89, 66.28 ± 6.55 and 553 ± 82.17 respectively. Respective values in sediment samples were found to be 44.59 ± 4.58, 67.64 ± 7.93, 782 ± 108. Relevant radiation hazard indices and dosimetric parameters were calculated and compared with the world average data recommended by US-EPA. Analytical results show non-negligible radiation hazards to the surrounding populace. Measured data will be useful to monitor any change of background radioactivity in the surrounding environment of RNPP following its operation for the generation of nuclear energy.

Simulation of channel dynamics of the Padma river considering seasonal variations: A GIS and statistical approach

The Padma river, for being dynamic, is subjected to frequent and irregular shifting, which creates various socioeconomic, ecological, and environmental threats. Besides, due to having seasonal influences, these threats become more intense during the monsoon period than the dry season. Considering these issues, the present study aims to investigate the spatiotemporal changes of the Padma river during 1988–2019 with seasonal variations, also simulating the changes till 2035 using multi-temporal satellite imageries. GIS and ARIMA model is used to perform spatiotemporal analysis and simulation, respectively. This study focused on the lateral shifting of 21 cross-sections along the Padma river channel flowing through 19 upazilas of six (06) districts in the northwest side of Bangladesh. The study finds that the width of the channel changes so frequently to its right and left sides during the last 31 years. The width increases in the summer season, indicating destruction of the river vicinity over time. The highest lateral shifting of the channel has also occurred at the Bagha and Daulatpur upazilas. The river is likely to be shifted more than 11 km and 13 km (winter and summer, respectively) in the next 16 years, along with the cross-section X10 at Bagha and Daulatpur upazila. Besides, the river channel's sinuosity has decreased till 2011 while it has increased suddenly in 2019. On the other hand, the braided index of the river has increased till 2011 and fell in 2019.

Resistance\u2010guided isolation and characterization of antibiotic\u2010producing bacteria from river sediments

BackgroundTo tackle the problem of antibiotic resistance, an extensive search for novel antibiotics is one of the top research priorities. Around 60% of the antibiotics used today were obtained from the genus Streptomyces. The river sediments of Bangladesh are still an unexplored source for antibiotic-producing bacteria (APB). This study aimed to isolate novel APB from Padma and Kapotakkho river sediments having the potential to produce antibacterial compounds with known scaffolds by manipulating their self-protection mechanisms.ResultsThe antibiotic supplemented starch-casein-nitrate agar (SCNA) media were used to isolate antibiotic-resistant APB from the river sediments. The colonies having Streptomyces-like morphology were selectively purified and their antagonistic activity was screened against a range of test bacteria using the cross-streaking method. A notable decrease of the colony-forming units (CFUs) in the antibiotic supplemented SCNA plates compared to control plates (where added antibiotics were absent) was observed. A total of three azithromycin resistant (AZR) and nine meropenem resistant (MPR) isolates were purified and their antagonistic activity was investigated against a series of test bacteria including Shigella brodie, Escherichia coli, Pseudomonas sp., Proteus sp., Staphylococcus aureus, and Bacillus cereus. All the AZR isolates and all but two MPR isolates exhibited moderate to high broad-spectrum activity. Among the isolates, 16S rDNA sequencing of NAr5 and NAr6 were performed to identify them up to species level. The analyses of the sequences revealed that both belong to the genus Streptomyces.ConclusionsThe results from these studies suggest that manipulation of the self-resistance property of APB is an easy and quick method to search for novel APB having the potential to produce potentially novel antibacterial compounds with known scaffolds.

Influence of Stocking Density on Growth Performance of Labeo bata in Cage at River Padma, Rajshahi, Bangladesh

As a result of climate change, aquaculturists are seeking adaptive culture techniques for sustainable aquaculture. In this case, cage culture is a suitable technique that can mitigate the challenge of climate change, but due to the lack of knowledge of proper stocking density, often productions are not satisfactory. Therefore, the experiment was conducted to evaluate the influence of stocking density on growth and production of an endangered minor carp bata (Labeo bata) in cages for a period of 120 days in Padma River, Rajshahi, Bangladesh. On an average initial weight of bata fingerling of 5 g was stoked in cages under three treatments each with containing three replications using three different stocking densities (106, 71 and 35 fingerling/m3 for T1, T2 and T3, respectively). Supplementary feed (3% per body weight) was given to the cultured species twice in a day. The mean values of water temperature, transparency, pH and dissolved oxygen were in suitable range throughout the experimental period. Significantly (p<0.05) highest mean gross weight (85.82±0.70 g), specific growth rate (2.37± 0.02%), survival rate (83± 3.00%) and food conversion ratio (2.27± 0.03) was found in T3 rather than T2 and T1. The net production in terms of biomass (18.23±2.43 kg/cage) was significantly (p<0.05) higher in T2.The study suggests that, treatment T2 (71 fingerling /m3) as the optimum stocking density to produce maximum production by cage culture of Labeo bata.

Machine learning algorithm-based risk assessment of riparian wetlands in Padma River Basin of Northwest Bangladesh.

Wetland risk assessment is a global concern especially in developing countries like Bangladesh. The present study explored the spatiotemporal dynamics of wetlands, prediction of wetland risk assessment. The wetland risk assessment was predicted based on ten selected parameters, such as fragmentation probability, distance to road, and settlement. We used M5P, random forest (RF), reduced error pruning tree (REPTree), and support vector machine (SVM) machine learning techniques for wetland risk assessment. The results showed that wetland areas at present are declining less than one-third of those in 1988 due to the construction of the dam at Farakka, which is situated at the upstream of the Padma River. The distance to the river and built-up area arethe two most contributing drivers influencing the wetland risk assessment based on information gain ratio (InGR). The prediction results of machine learning models showed 64.48% of area by M5P, 61.75% of area by RF, 62.18% of area by REPTree, and 55.74% of area by SVM have been predicted as the high and very high-risk zones. The results of accuracy assessment showed that the RF outperformed than other models (area under curve: 0.83), followed by the SVM, M5P, and REPTree. Degradation of wetlands explored in this study demonstrated the negative effects on biodiversity. Therefore, to conserve and protect the wetlands, continuous monitoring of wetlands using high resolution satellite images, feeding with the ecological flow, confining built up area and agricultural expansion towards wetlands, and new wetland creation isessential for wetland management.

Squeezing Out and Characterization of Silicon from Sand by Mg- Thermite Reduction Process

Background: Sand is one of the efficient sources of silicon. We get quite easily the plethora of sand from the river side, Bangladesh. Utilization of the superfluous sand can be assisted to enhance our economy. Methods: In this work, silicon is extracted from sand by metal–thermite reduction process and the sample of sand is collected from padma river Rajshahi, Bangladesh. The process is environmentally benign and low cost. The reduction of the sand was performed with Mg powder, and purification was done by leaching out with HCl and HF. We have studied the structural properties, chemical nature and physical morphology. Results and Conclusion: X-ray Diffraction (XRD) confirmed that the presence of elemental Si in the samples produced by Mg-thermite reduction process and the particle size was found 25.72±1.3 nm in an average. Surface morphology has been studied using Scanning Electron Microscopy (SEM) and the particle size seemed around 30 to 40 nm which was comparable to the obtained particle size from XRD. Fourier transform infrared spectroscopy (FTIR) showed the presence of Si-Si bonding in the investigating materials. The chemical nature of the sand has been studied by X-ray Fluorescence (XRF) analysis. Silicon content of sand was found about maximum 80%.

Evaluation of the river Padma morphological transition in the central Bangladesh using GIS and remote sensing techniques

ABSTRACT Since decades, the characteristics of the major tributaries and distributary channels and their dynamics over time have got significant scientific interests. Recently, thanks to Remote Sensing (RS) and Geographical Information System(GIS), new studies focused on evaluating the river dynamics at the reach scale appeared, covering also remote regions worldwide. This study provides an overview of the morphological changes of the River Padma, Bangladesh, during the last four decades. The River Padma was very dynamic and constantly changed its position, planform, and other morphological properties because of variation in flow, sedimentation, and boundary condition. Five sets of geo referenced Landsat images from 1979 to 2019 were scrutinized using ERDAS Imagine and ArcGIS to visualize the erosion, accretion, bank line migration, bar growth, as well as changes in planform, and channel bed elevation. The results indicated that bank and channel positions, as well as central bars along with geometry, changed dramatically over time, and the River Padma turned into sinuous-braided from straight-wandering planform. From 1989 to 1999, heavy discharge during the monsoon season eroded around 283 km2 land along 100 km reach. This study also revealed that the average width of the River Padma increased about 3.5 km and the overall bar area increased by 40%. This study demonstrated that the right bank of the River Padma was more unstable than the left bank during the last four decades. The findings of this study might help to prepare better management strategies for agricultural land, homestead as well as inland navigation projects across the floodplain.

River channel migration and land-use/land-cover change for Padma River at Bangladesh: a RS- and GIS-based approach

This study has been carried out to evaluate the river shifting and assessment of related effect on the land-use/land-cover using geographic information system (GIS) and remote sensing (RS) techniques between 1955 and 2016 for Padma River at Bangladesh. Alluvium is eroding chronically due to the rushing stream flow; therefore, people of this region are poor and government loss national assets each year that reflects the direct effect on the economy. The standard topographical map of 1955 and satellite images of 1973, 1987, 1999, 2011 and 2016 were used in the study. Impact assessment on land use/land cover around 5 km from the stream centerline of 1973 was obtained. This studied has been carried out in three steps: (1) analyzed migration rate from 1955 to 1973; (2) analyzed migration rate from 1973 to 2016 and (3) assessed migration rate impact on land-use/land-cover change using GIS and RS techniques. Normalized difference of water index technique was used for identification of land and water boundary. The maximum likelihood supervised image classification was applied to detect the land-use/land-cover type and identify erosional impact with best accuracy. Results of long-term river channel migration showed that the land area is influencing with river erosion, settlement area is increasing, vegetation area is decreasing, but sand bar, water body and cultivated land area are oscillating. The satellite images were collected during winter and dry seasons (from November to January), when stream flow is limited for a lower amount of rainfall. Maximum erosion and management plan are critical for area at section 2 right bank 1955 to 1973. On the other hand, a minor improvement of embankment is necessary at section 2 because erosion occurs from 1973 to 1987, 1973 to 1999 and 1973 to 2011 at left bank; at section 4 because erosion occurs from 1973 to 2011 at right bank; and at section 5 because erosion occurs from 1955 to 1973 at left bank. New land developments occur at section 3 left bank from 1973 to 2016; without it, the maximum occurrence of accretion number was found from 1973 to 2016 at section 2 right bank, section 3 left bank, section 4 left bank, section 5 left bank that help for river bank management, large-scale planning to prevent flood and reduce the property loss.

Study of the climate change impact on fishers’ livelihood near the Padma river in Munshiganj, Bangladesh

Climate change is a contemporary global threat to the whole world especially in the coastal area like Bangladesh. Bangladesh is extremely vulnerable to climate change impacts because of its geographical location. This research is an attempt to assess the impacts of climate change on fishersʹ livelihood of a selected climate hotspot zone Munshiganj. In the study area, the average sex ratios of male and female were 56.67% and 43.33%, respectively and their religion ratio were Islam 45% and Hindu 55%. There was 60% nuclear family and 40% joint family. About 86.4% house was tin-shed and drinking water source was only tube well. In Munshiganj, 11% fishers were illiterate, 27% had primary, 38% had secondary, 16% had higher secondary and 8% had bachelor. Most of the people about 59% were depended on Upazila Health Complex for their health issues. Highest percentage of fishers about 40% had an annual income of 20,001 to 24,000 BDT. About 62.7% fishers were agreed with the statements: reduce fish production, damage fishing ground, blockage of fish migration road, damage biodiversity, increasing temperature, enhance soil erosion, reduce rainfall, siltation, water flow, storm frequency, changing spawning season, decrease fish production, extinction fish species. In study area, women and children are affected severely i.e. malnutrition, education, treatment, early marriage etc. The present study clearly indicates that there are visible changes in livelihood condition of fishers‟ in the study areas of Munshiganj.
 Asian J. Med. Biol. Res. December 2020, 6(4): 777-784

Climate Change and Anthropogenic Interferences for the Morphological Changes of the Padma River in Bangladesh

This research aims to identify the morphological changes of the Padma River due to the effects of anthropogenic climate change. The morphological changes were measured by aerial satellite images and their historical comparison, terrestrial survey, sedimentation in the riverbed, water flow, water discharge, siltation, and erosion along the river, etc. The Padma River has been analyzed over the period from 1971 to 2020 using multi-temporal Landsat images and long-term water flow data. The climatic parameters data related to temperature and rainfall were collected from 21 metrological stations distributed throughout Bangladesh over a 50-year period (1965-2015) to evaluate the magnitude of these changes statistically and spatially. The Padma, traditionally considered as a dominantly meandering river, is switching over into a braided river due to its highly susceptible nature of erosion and deposition. Results reveal that the tidal range is high during the dry season and increases from upstream to downstream of the river. Climate change may bring changes upstream by changing rainfall intensity, flood severity, and extreme temperature. More inundation can occur due to sedimentation, and more bank erosion can occur at the same time. An exponential increase of morphological activity with increased river flow, water discharge, bank erosion might substantially increase in the future. The changes in the flow introduced by climate change would impact the morphology of the Padma River of Bangladesh during the monsoon. A major change has been observed in the location of the bank and channel, as well as bars, along with their geometry and morphology over time. It is also observed that the bank line is not stable and migrated continuously. The overall width of the Padma River is varied significantly during the last 50 years. Maps and Landsat images represented that the river channel is shifting abnormally. Both climatic parameters and anthropogenic activity play an important role in fish biology and production. From this study, it is hypothesized that this assessment’s findings might help understand the overall hydrodynamic and morphological nature of the Padma River. It will suggest possible future developmental works that might be implemented on this river.