Jamuna River Research Articles

Stabilization of the Lower Jamuna River in Bangladesh—Hydraulic and Morphological Assessment

This paper presents a hydraulic and morphological analysis of the Lower Jamuna in Bangladesh with a focus on two key bifurcations that are important for stabilization of the Lower Jamuna reach. We used ground measurements, historical data, multispectral satellite images from various sources as well as numerical models. We carried out hydraulic analyses of the changes and their peculiarities, such as flow distributions at the bifurcation and hysteresis of the stage–discharge relationships. We supplemented our analysis by using numerical models to simulate discharge distribution at the bifurcations under various flow and riverbed conditions. We developed an advanced and automated satellite image processing application for the Lower Jamuna, referred to as Morphology Monitor (MoMo), using the Google Earth Engine. MoMo was found to be an effective tool for a rapid assessment and analysis of the changes in deep-channel and sandbar areas. It is also useful for monitoring and assessing riverbank and char erosion and accretion, which is important not only for morphological but also ecological impact assessment. The application can be adapted as an operational tool as well. Furthermore, we assessed the evolution of deep channels at the bifurcations based on regularly and extensively measured bathymetry data. The analysis was carried out in complement with morphological modeling, particularly for short-term prediction. In this paper we present the major findings of the analysis and discuss their implications for adaptive river management.

Process-based modeling deriving a long-term sediment budget for the Ganges-Brahmaputra-Meghna Delta, Bangladesh

Fluvial, tidal, and combined hydro-morphodynamics interaction in a complex, seasonal, sediment transport regime has been the subject of extensive research. It becomes particularly challenging when there is limited data. The Ganges-Brahmaputra-Meghna (GBM) Delta is one example of a huge system lacking data. Bathymetric data simultaneously covering the rivers and estuaries is hardly present, let alone sequences of bathymetries or a system-wide sediment budget. Hence it is difficult to understand and predict future developments. This research aims to make a sediment budget for the GBM delta with a process-based model. It is a first-ever sediment budget simulation for the GBM system. A process-based morphological model, Delft3D, has been used to reproduce the bathymetric evolution over time and the associated sediment budget. This chapter demonstrates the possibilities for the application of a robust modeling system to assess the morphodynamic evolution and sediment budget and pathways. The Ganges and Jamuna rivers carry sediment load in the ranges of 216–1038 million tonnes/yr and 80–228 million tonnes/yr respectively. The total accumulation in the estuary system is 1150 million tonnes/yr, out of which more than eighty percent of sediment is in suspension. The model results show that about 22% of the total sediment coming into the system is deposited in the floodplains and tidal plains and causes river morphology changes. The rest of the sediment is lost to the pro-delta, to the deep ocean bed, or leaves the domain. The results also indicate that Padma, Gorai, Pussur-Sibsa, Bishkhali, Shahbajpur channel, Lower Meghna, Tentulia Channel, and Arial Khan rivers are mainly in the aggrading phase, whereas, the Ganges, Jamuna, and Baleshwar are in the degrading phase. This particular delta model offers many opportunities to compare with sediment data, where it deals with a poorly surveyed area.

Geographical Information System Approach to Delineate the Watershed’s Morphometric Parameters for Sustainable Hydrological Modeling of Barind Region, Bangladesh

Water is an important resource of the earth’s surface and it is integral for all on this planet. The availability or the scarcity of water depends on the watershed characterizes that consider the basic, linear, and shape parameters of any waterbody. The objective of the study was to delineate 14 morphometric parameters in the Barind region (Dinajpur district, Bangladesh) for sustainable hydrological modeling. An ASTER-DEM of 30-meter resolution data, geographical information system (GIS), and Remote sensing technique were used for extracting drainage components of interest region. The whole study region was covered by the flow of the Purnovoba river, Jamuna river, Atrai river (part-1 and part-2). Research results found that the Purnovoba river had a high bifurcation ratio (0.9982) that defined hydrologically more disturbed than the other three watershed areas and it had a high stream frequency (0.8332) that denoted rocky having low infiltration capacity. Jamuna river had a low drainage density (0.7322) that defined more vegetation having higher permeability. Besides, the Jamuna river had the lowest no. of stream order that was insignificant in the steady runoff process and less prone to cause a flash flood. The research predicted that the availability of groundwater might decrease to Jamuna river in the future as it had the lowest basin area (217.42 sqr. km ) and perimeter (114.90 km) and the basin surface slope would become gentle to Atrai river part-1 for the lowest length of overland flow (0.6072). Purnovoba river experienced the lowest form factor (0.2351) which indicated the most possibility for erosion. The elongated ratio of all basins was greater than 0.5 which considered all the shapes were more elongated. These findings will help for further modeling of an integrated watershed for sustainable hydrological models in the Barind region.

Land transform and its consequences due to the route change of the Brahmaputra River in Bangladesh

ABSTRACT This study attempts to analyse the historical records and satellite images, and determines the dynamic morphological changes using Remote Sensing (RS) and Geographic Information System (GIS) techniques in order to delineate the paleo-course and the dimensions of the Brahmaputra River. Additionally, land transformations due to route change from Old Brahmaputra-Meghna to Jamuna River were also evaluated. The study revealed that owing to the route changes, the Jamuna River grabbed about 2817 km2 of invaluable land resources that were well developed. Whereas Brahmaputra-Meghna river course was associated with ∼4563 km2 newly developed lands which are currently being used for settlement, business, and agricultural purposes. Thus, if the river system changes its route again and follows the former path, the lands associated with the Brahmaputra-Meghna river course may again be scoured by the river. Hence, it is suggested that the necessary preparations should be adopted to maintain the current flow of the Brahmaputra through the Jamuna River which may help to protect the newly developed landmasses. Since the present route is straighter than the old Brahmaputra course, it would be easier to manage and maintain the current route of the Brahmaputra via the Jamuna River. Finally, a sustainable river basin management approach may be lucrative for both local as well as international communities.

Multi-scale flooding hazards evaluation using a nested flood simulation model: case study of Jamuna River, Bangladesh

ABSTRACT We investigated the merits of performing multi-scale flood simulations with nested two-dimensional flood simulation models for flood risk management applications over an extended period with infiltration and evapotranspiration. For nested calculations, (1) inter-district, (2) district, and (3) regional scales were arranged as three levels in the nested model. Because the nested method can be useful for flat land, the Gaibandha District in Bangladesh was chosen for the study area. This area is a typical flood-prone area that is inundated frequently by flood flow from the Jamuna River. First, we performed a year-round flooding simulation for the year 2007 by focusing on a monsoon flood, and validated the results via satellite images. Second, we evaluated the differences of floods in the case of 2.33- and 100-year return periods by using discharge data produced by a flood frequency analysis. We successfully simulated the flooding in each nested level for 2007, and this enabled us to evaluate the flood risks at different scales. In addition, we delineated the flood extent for different return periods and clarified the relationship between the peak water level of the river and the flood extent. The nested method proved to be advantageous because its implementation is not computationally demanding.

Marginal Lives and the Microsociology of Overhearing in the Jamuna Chars

ABSTRACT In the past decade, Bangladesh has made a shift to becoming an authoritarian state. What happens to everyday speech within the context of state repression and censorship? I take up this question by exploring the nature and fate of ‘overhearing’ as a mode of speaking, most often prefaced by, ‘I heard that,’ or ‘this is heard speech,’ among the underprivileged denizens of the chars in the Jamuna River during the 2014 National Elections. The interest in drawing attention to overhearing, as opposed to eavesdropping or rumouring to which overhearing bears a resemblance, is to highlight a mode of speaking that stands to fall victim to the disciplining of speech currently underway in Bangladesh. In disciplining overhearing we stand to loose a practice, which, despite being intermittent and ephemeral, espouses an aesthetic sensibility and extends socio-religious judgments into the realm of nature, increasing the scope for political critique.

Heavy Mineral Analysis of Jamuna River Sediments, Bangladesh

Abstract The Jamuna is one of the world’s most heavily sediment-laden braided river. Despite a major host for heavy mineral resources, the sediments of the Jamuna river are sparsely studied. A mineralogical and SEM-EDS investigation has been carried out in the middle part (along Sirajganj and Jamalpur district of Bangladesh) of the Jamuna river to appraise the grain size parameter, texture, depositional environment, heavy mineral distribution, and elemental composition of the heavy minerals. The results show that sediment samples are very fine to fine sand, moderate to well sorted, near symmetrical to strongly fine skewed, and mesokurtic to very leptokurtic. Uniform to graded suspension mechanisms are the processes for sediment deposition. Heavy minerals accumulation ranges from 0.5% to 9.33%, and the assemblages are predominantly marked by epidote, amphibole, followed by opaque (magnetite and ilmenite), garnet, zircon, sillimanite, apatite, tourmaline, rutile, kyanite, staurolite, monazite, chlorite, and titanite. The percentage of amphibole, garnet, and zircon decreases downstream and epidote increases in the same direction. The calculated zircon-tourmaline-rutile index (ZTR) varied between 3 to 13%, average apatite-tourmaline index (ATi), garnet-zircon index (GZi), rutile-zircon index (RuZi) and staurolite-zircon index (SZi) values are 54.55%, 75%, 38.68%, and 30% respectively. The Brahmaputra-Jamuna river sediments are derived from mixed-source regions (e.g., Shillong Plateau, Indo-Burman Ranges, and the Himalayas). The abundance of subangular to angular, high relief heavy mineral grains with sharp edges on the surface, conchoidal fractures, deep troughs, and breakage blocks infer that the provenance is close to the depositional area. The presence of rounded to sub-rounded, smoother surface with adhering particles, arcuate steps, and low to medium relief indicate the long-distance transportation of heavy mineral grains through fluvial environment.

River Bank Erosion, Induced Population Migration and Adaptation Strategies in the Sirajganj Sadar Upazila, Bangladesh

Riverbank erosion, a regular natural phenomenon in the lower confluence deltaic country like Bangladesh. Among the natural disaster effecting Bangladesh each year, river bank erosion is the most vulnerable in term of effected people and loss of assets. As a riverine country there are huge number of rivers and their tributaries and distributaries criss-crossed over the country, but the mighty three rivers like the Padma, Jamuna and Meghna are mostly known for the erosional characteristics. River bank erosion possesses as a significant, endemic and recurrent natural disaster in Bangladesh by these rivers. This research is designed to explore the erosional pattern of the river Jamuna and its impact on population migration and the adaptation strategy of the migrants. For the study primary data were collected from the study area through questionnaire survey, FGD and mapping analysis while secondary data were collected from published and unpublished reports of different offices such as land office, union parisad office, census report, BBS, WDB etc. However, to analyze the trend of erosion mapping analysis was conducted through ArcGIS 10.3 and for statistical analysis SPSS software was used. The research findings indicate that the Jamuna is a highly dynamic river in term of erosion. Due to its severity and dynamic erosional pattern possess mass number of people to be displaced by losing settlements and agricultural land. River bank erosion of Jamuna River invites many obligatory problems at different stages of displacements like loss of residence, household assets, agricultural land etc. Though it pushes the victims to readjust all their activities associated to livelihood pattern as an adaptation strategy with a newer socio-environmental situation, but very often becomes unable to recover the damage even spending considerable time. From this point of view, river bank erosion needs to be considered as a unique disaster and give attention to take comprehensive riverbank erosion management policy, so that problem can be minimized to a tiny scale.

Livelihood Improvement of Farmers through Agroforestry Practices in Teesta and Jamuna River Basins

Agroforestry is one of the most sustainable land management systems practiced around the world due to the socioeconomic benefits to farmers. In Bangladesh, farmers practice agroforestry, applying indigenous knowledge. The objectives of the study are to explore the dominant agroforestry systems and species preferred by and to assess the socio-economic impact of agroforestry technologies on their livelihoods of farmers of the Char dwellers in Jamuna and Teesta river basins. The study was conducted at four Char Upazillas such as Kazipur, Shariakandi, Kaunia and Dimla. A total 120 farmers were surveyed during the research period using structured questionnaire with both open and closed ended questions. The majority of the respondents (56.67%) having low score in adoption of traditional agroforestry practices. Most of the farmers (94.17%) in Teesta and Jamuna river basins are practicing traditional homestead agroforestry system. The most frequent strategy was boundary tree plantation (44.17%) followed by scattered tree plantation technique on composite planting system, and the alley of cropland. A total of 41 tree species are abundant in Char areas of Teesta and Januna basins. Eucalyptus (Eucalyptus camaldulensis) is widely adaptable in Bangladesh including Char areas followed by Mango (Mangifera indica) in homestead besides, Mahagony (Swietenia mahagoni) is another abundant species planted in croplands boundaries of Char areas along with Akashmoni (Acacia auriculiformis). The farmers mentioned different problems they were facing in practicing agroforestry but ‘shade cast by trees’ was the major problem. Majority farmers of Char areas plant trees in homestead for fruits (63.33%) and in cropland for fuel wood (95.83%) and timber production (82.50%). Farmers’ livelihoods improved enormously by practicing agroforestry as they have more access to food, fodder and fuel wood which is reflected by greater access to livelihood capitals except social capital. However, the farmers have experienced increased incidences of pests and diseases to annual crops and trees. Agroforestry practices increases species diversity, ensure economic return and sustain farmers’ livelihoods. The respondents, local leaders and experts suggested the constrains of adopting agroforestry in Char areas are lack of awareness, education, technical skills, capital, technical assistance, interest, marketing and transportation facilities at the study areas . The government should initiate some agroforestry focused projects, especially in the Char areas for the capacity building of the farmers and equip them with the new farming techniques through trainings and orientation workshops. The farmers should be provided scientific guidance about suitable tree species grown on agricultural land with field crops, their silvicultural operations and tree management practices along with free services and inputs including seeds, seedlings and loan schemes for promoting agroforestry.

Impacts of Dredging on Fluvial Geomorphology in the Jamuna River, Bangladesh

Jamuna, a major braided river in Bangladesh, has an enormous hydrological impact on the surrounding areas and streams. Erosion and sedimentation in the Jamuna river cause a large flow fluctuation and floods round the year. Bangladesh Water Development Board has initiated a pilot capital dredging project in the Jamuna river in 2011-2012, aiming to guide the flow to reduce the risk of failure of the city area and right guide bundh of the Jamuna Bridge. This study explores the long-term role of dredging on river morphology us-ing erosion-sedimentation numerical modeling approaches. Primary data were employed in numerical models to estimate the erosion-sedimentation and compared outputs with the real-time cross-sectional variation at selected sections along the reach during 2012-2013. The analysis suggested that the rate of sedimentation is higher (60% to 80%), where the dredging alignment crosses through the existing sandbar/char. Moreover, a cross-section com-parison revealed that the channel near Sirajganj Hardpoint shifted towards the left (east) bank, and the channel within the study area developed very fast along the right (west) bank. However, satellite image analysis revealed that the major bankline shifting occurred from 2000 to 2010 and the channel shifting was observed from 2014 to 2018 along the reach, mostly, after the construction of some river training works. The variation of the channel per-sistence (40% - 100%) selected part of the study area in the channel inci-dence map, indicating the rapid dynamic behavior of the river morphology. This study showed a good agreement of measured data and simplified em-pirical relationships to predict the long-term morphodynamic behavior of the braided Jamuna river.

A Century of Riverbank Protection and River Training in Bangladesh

Protecting against riverbank erosion along the world’s largest rivers is challenging. The Bangladesh Delta, bisected by the Brahmaputra River (also called the Jamuna River), is rife with complexity. Here, an emerging middle-income country with the world’s highest population density coexists with the world’s most unpredictable and largest braided, sand-bed river. Bangladesh has struggled over decades to protect against the onslaught of a continuously widening river corridor. Many of the principles implemented successfully in other parts of the world failed in Bangladesh. To this end, Bangladesh embarked on intensive knowledge-based developments and piloted new technologies. After two decades, successful, sustainable, low-cost riverbank protection technology was developed, suitable for the challenging river conditions. It was necessary to accept that no construction is permanent in this morphologically dynamic environment. What was initially born out of fund shortages became a cost-effective, systematic and adaptive approach to riverbank protection using improved knowledge, new materials, and new techniques, in the form of geobag revetments. This article provides an overview of the challenges faced when attempting to stabilize the riverbanks of the mighty rivers of Bangladesh. An overview of the construction of the major bridge crossings as well as riverbank protection schemes is detailed. Finally, a summary of lessons learned concludes the impressive progress made.

Millet-Jute-T. Aman Cropping Pattern for Increasing System Productivity in the Active Brahmaputra-Jamuna Floodplain Chars

Increasing system productivity in a planned way is an important base for attaining food security, where bringing marginal land like Charland under intensive crop cultivation is highly desirable. The field trial was conducted in the Charland of the Jamuna River under Saghataupazilla of Gaibandha during 2017- 18 & 2018-19 to increase the productivity and profitability through the development of three crops-based improved cropping patterns instead of the local practice (double-crop). Three crops based improved cropping pattern namely Millet (BARI Kaon-2)-Jute (O-9897)-T. Aman (Gainja) was compared with the existing cropping pattern of Millet (Local)-Fallow-T. Aman (Gainja). The experiment was laid out in six dispersed replications maintaining RCB design. The introduced improved cropping pattern produced the higher system productivity based on rice equivalent yield, REY (12.95 t ha-1), than the existing cropping pattern (4.20 t ha-1), which is three times higher than the existing pattern. Total field duration and turnaround time were 323 and 42 days, respectively in improved pattern and 215 and 150 days, respectively in the existing pattern, which revealed that 108 days more could be made productive through the introduction of improved cropping pattern. The alternate pattern increased production efficiency and land-use efficiency by 35% and 30%, respectively than that of the existing cropping system. The gross margin was also three times higher in the improved cropping pattern (1, 41,600 Tk ha-1 yr-1) compared to the farmers’ existing cropping pattern (38,350 Tk ha-1 yr-1). The marginal benefit-cost ratio (MBCR) was calculated 2.44 in an improved cropping pattern over the existing cropping pattern. The inclusion of an extra one crop (Jute) in the existing cropping pattern and replacement of the local millet variety by high yielding variety (BARI Kaon-2) could play a significant role to increase the system productivity as well as profitability in the Charland of Saghata, Gaibandha.
 The Agriculturists 2020; 18(1) 129-136

Predicting Channel Conveyance and Characterizing Planform Using River Bathymetry via Satellite Image Compilation (RiBaSIC) Algorithm for DEM-Based Hydrodynamic Modeling

Digital Elevation Models (DEMs) are widely used as a proxy for bathymetric data and several studies have attempted to improve DEM accuracy for hydrodynamic (HD) modeling. Most of these studies attempted to quantitatively improve estimates of channel conveyance (assuming a non-braided morphology) rather than accounting for the actual channel planform. Accurate representation of river conveyance and planform in a DEM is critical to HD modeling and can be achieved with a combination of remote sensing (e.g., satellite image) and field data, such as water surface elevation (WSE). Therefore, the objectives of this study are (i) to develop an algorithm for predicting channel conveyance and characterizing planform via satellite images and in situ WSE and (ii) to estimate discharge using the predicted conveyance via an HD model. The algorithm is named River Bathymetry via Satellite Image Compilation (RiBaSIC) and uses Landsat satellite imagery, Shuttle Radar Topography Mission (SRTM) DEM, Multi-Error-Removed Improved-Terrain (MERIT) DEM, and observed WSE. The algorithm is tested on four study areas along the Willamette River, Kushiyara River, Jamuna River, and Solimoes River. Channel slope and predicted hydraulic radius are subsequently estimated for approximating Manning’s roughness factor. Two-dimensional HD models using DEMs modified by the RiBaSIC algorithm and corresponding Manning’s roughness factors are employed for discharge estimation. The proposed algorithm can represent river planform and conveyance in single-channeled, meandering, wandering, and braided river reaches. Additionally, the HD models estimated discharge within 14–19% relative root mean squared error (RRMSE) in simulation of five years period.

Morpho-Genetic Divergence and Adaptation of Anadromous Hilsa shad (Tenualosa ilisha) Along Their Heterogenic Migratory Habitats

Migration of an anadromous fish to heterogeneous environment continuously enforces a selective pressure that incorporates a wide range of life-history strategies by which individuals adapt to the prevailing conditions. Therefore, we used the landmark-based morphometric truss network method and nextRAD genotyping-based putatively adaptive SNP loci dataset to know how the anadromous Hilsa shad (Tenualosa ilisha) morpho-genetically adapt to the heterogeneous habitats across their migratory routes by investigating 300 individuals, collected from nine strategic sampling sites covering sea, estuary, and upstream freshwater rivers. Different multivariate and clustering analyses revealed that the riverine populations were morphometrically wider (broad type) than the estuarine and marine populations (slender type). In the case of riverine population, the north-western turbid population (the Padma and Jamuna rivers) had wider body depth than the north-eastern clear water population (the Meghna river). The linear model and spatial multivariate analyses further revealed that the outcomes of morphometric dataset were in complete concordance with the results of putatively adaptive SNP loci dataset for different Hilsa shad populations. The GO enrichment analysis of the 36 genes, which are encoded by the putative adaptive SNP loci, supported the presence of multiple genes involved in the growth, metabolism, homeostasis and osmoregulation related functions. Several non-mutually exclusive hypotheses were attributed to explain the observation of continuum differentiation at both phenotypes and genotypes: i) the genetic variation largely determines the morphometric discrimination, ii) the interactive evolutionary processes and salinity gradients predominantly contribute to the morphogenetic divergence between the marine-estuarine and the freshwater riverine populations, iii) the salinity levels influence the genotypes leading to the phenotypic plasticity, and iv) the local environmental heterogeneity may contribute to the morphogenetic divergence between the riverine populations. Finally, we concluded that the genetic adaptation, phenotypic plasticity and interactive ecological and evolutionary consequences jointly determine the morphogenetic divergence of Hilsa shad. The interaction of all of these forces and their relative strength in heterogeneous environments, however, made it rather challenging to determine the most probable selective pressure, which has shaped the Hilsa shad morphogenetic divergence across their diverse migratory habitats.

Three-Dimensional Flow Characteristics in Slit-Type Permeable Spur Dike Fields: Efficacy in Riverbank Protection

This paper focuses on finding efficient solutions for the design of a highly permeable pile spur (or slit type) dike field used in morphologically dynamic alluvial rivers. To test the suitability of different arrangements of this type of permeable pile spur dike field, laboratory experiments were conducted, and a three-dimensional multiphase numerical model was developed and applied, based on the experimental conditions. Three different angles to the approach flow and two types of individual pile position arrangements were tested. The results show that by using a series of slit-type spurs, the approach velocity of the flow can be considerably reduced within the spur dike zone. Using different sets of angles and installation positions, this type of permeable spur dike can be used more efficiently than traditional dikes. Notably, this type of spur dike can reduce the longitudinal velocity, turbulence intensity, and bed shear stress in the near-bank area. Additionally, the deflection of the permeable spur produces more transverse flow to the opposite bank. Arranging the piles in staggered grid positions among different spurs in a spur dike field improves functionality in terms of creating a quasi-uniform turbulence zone while simultaneously reducing the bed shear stress. Finally, the efficacy of the slit-type permeable spur dike field as a solution to the riverbank erosion problem is numerically tested in a reach of a braided river, the Brahmaputra–Jamuna River, and a comparison is made with a conventional spur dike field. The results indicate that the proposed structure ensures the smooth passing of flow compared with that for the conventional impermeable spur structure by producing a lower level of scouring (low bed shear stress) and flow intensification.

The interplay between structural flood protection, population density, and flood mortality along the Jamuna River, Bangladesh

Levees protect floodplain areas from frequent flooding, but they can paradoxically contribute to more severe flood losses. The construction or reinforcement of levees can attract more assets and people in flood-prone area, thereby increasing the potential flood damage when levees eventually fail. Moreover, structural protection measures can generate a sense of complacency, which can reduce preparedness, thereby increasing flood mortality rates. We explore these phenomena in the Jamuna River floodplain in Bangladesh. In this study area, different levels of flood protection have co-existed alongside each other since the 1960s, with a levee being constructed only on the right bank and its maintenance being assured only in certain places. Primary and secondary data on population density, human settlements, and flood fatalities were collected to carry out a comparative analysis of two urban areas and two rural areas with different flood protection levels. We found that the higher the level of flood protection, the higher the increase of population density over the past decades as well as the number of assets exposed to flooding. Our results also show that flood mortality rates associated with the 2017 flooding in Bangladesh were lower in the areas with lower protection level. This empirical analysis of the unintended consequences of structural flood protection is relevant for the making of sustainable policies of disaster risk reduction and adaptation to climate change in rapidly changing environments.

Fish species using the fish passage between Jamuna and Bangali river at Sariakandi, Bogra

Sariakandi fish pass is unique connecting Jamuna and Bangali rivers through an engineered channel. A study was conducted on the fish pass aiming to improve fish diversity in north-west Bangladesh. Sampling at the fish pass, market census, interviewing the locals and focus group discussion were done to collect data from the study area. A total of 69 fish species under 9 orders and 26 families were recorded. Cypriniformes (22 species) was the most dominant order followed by Siluriformes (21 species), Perciformes (13 species), Clupeiformes (4 species), Synbranchiformes (4 species), Osteoglossiformes (2 species), Mugiliformes (1 species), Anguilliformes (1 species) and Tetraodontiformes (1 species). In total 30 threatened species in Bangladesh and globally recognized 9 species were recorded. This fish pass is not working during the dry or winter seasons but helps in the diversified fish migration diversity of Bengali and Jamuna river system during the flood time of Bangladesh. The present study recommends establishing effective fish passages in flood protection structures or dams in Bangladesh to retain the connectivity of fish migration routes and the improving of fish diversity.
 J. Biodivers. Conserv. Bioresour. Manag. 2019, 5(2): 53-62

Genetic relationship among indigenous sheep population of Bangladesh

The study was conducted to investigate the genetic relationships among indigenous sheep population of Bangladesh (Barind, Jamuna river basin, Coastal and Garole sheep) using microsatellite markers. A total of 96 blood samples were collected from adult sheep of Barind (24), Jamuna River Basin (24), Coastal (24), Garole(10) and available Chotanagpuri (10) sheep. Chotanagpuri sheep was used as an outgroup population. DNA was extracted from blood samples using QIAGEN DNA Mini extraction kit and was quantified using a nanodrop. FAO recommended 13 labeled microsatellite markers were used for polymerase chain reaction (PCR). PCR product was confirmed by 2% agarose gel electrophoresis and visualized by staining with ethidium bromide.The exact allele sizes in each primer were determined by GeneMaker V1.85 demo. Microsatellite tool kit and Dispan software package were used for calculation of allele frequency, number of alleles per locus, observed and expected heterozygosity and genetic distances (DA). The Dispan software was used to calculate inter-individual genetic distances. These distance values were used to construct an UPGMA tree. Results showed that average number of polymorphic alleles per locus varied from4 in HUJ616 to 12 in MAF70. Observed heterozygosity was also varied from 0.54±0.04 in Coastal to 0.63±0.03 in Barind sheep population. Genetic distance between Jamuna river basin and Barind was lowest (0.01) and between Garole and Costal was highest (0.17). Garoleand Chotonagpuri sheep has higher genetic distance from other three sheep populations. Phylogenetic dendogram showed that sheep of Jamuna river basin and barind were belonged to same genetic group. Whereas, coastal, garole and Nagpur sheeps were shown higher genetic distances from Jamuna river basin and coastal sheep. Considering findings of this study it may be concluded that the Barind and Jamuna river basin sheep belongs to a similar genetic group while, Garole and Coastal sheep are belonging to two distinct genetic groups.
 Bang. J. Anim. Sci. 2019. 48 (1): 17-22

Occurrence and distribution of valuable heavy minerals in sand deposits of the Jamuna River, Bangladesh

A mineralogical and chemical investigation of surface and subsurface samples from the upper, middle and lower parts of the Jamuna River was carried out with a view to assessing the distribution and recovery potential of the heavy minerals ilmenite and garnet. The HM component in the Jamuna sands is ~10% consisting predominantly of amphibole, epidote and garnet with significant amounts of opaque minerals (ilmenite, magnetite, titanomagnetite, etc). A greater abundance of garnet was present in the fine to medium sized fractions (125–250 µm) and lower garnet concentrations were observed in the very fine sized fraction (<63 µm). The fine size fractions also have increased amounts of clays and clay-like minerals. Potentially high value HMs such as zircon and rutile were also concentrated in the <63 µm size fractions.The ilmenite grains are characterised by TiO2 content between 34.2 and 52.8 wt-% with low levels of impurities. The garnet geochemistry is more variable but dominated overall by almandine-rich compositions. The characteristic heavy mineral suite of garnet, epidote, amphibole, kyanite, and staurolite, as well as the garnet and ilmenite chemistry reveals the sediments are derived from mixed source areas of varying metamorphic grade (low to high) facies and igneous rocks. Based on these results, the Jamuna River sands have good potential for recovery and exploitation of both garnet and ilmenite.

Depositional conditioning of three dimensional training images: Improving the reproduction and representation of architectural elements in sand-dominated fluvial reservoir models

Fluvial deposits create significant hydrocarbon reservoirs, although their characterisation can be difficult due to their differing scales of heterogeneity. Whilst numerical modelling methods have advanced to statistically honour fluvial input datasets, geologically realistic features are often lost, impacting hydrocarbon recovery predictions. Two dimensional training images are often used to dictate what heterogeneity is inputted into multi-point statistics based reservoir models. In this study, a three dimensional training image is built, based upon depositional conditions derived from outcrop and modern satellite imagery data of a fluvial system. The aims of this study are to: identify the heterogeneity within the modern and outcrop data and to replicate it in a three dimensional training image; to model such heterogeneity using object-based, sequential indicator simulation and multi-point statistics; and to qualitatively and quantitatively (through static net-connectivity testing) analyse the reproducibility and geological realism of the generated reservoir models. Digital photogrammetric data from Tuscher Canyon, Utah, of the Lower Castlegate Sandstone and satellite imagery from the Jamuna River, northern India, are used to depositionally condition a three dimensional training image. This training image was then used to generate the multi-point statistics models, which were then tested against more traditional object-based and sequential indicator simulation reservoir models. Results indicated that object-based models realistically reproduced heterogeneous architectural elements, however, the connectivity of net-reservoir elements were unrealistically shaped and over-connected. The sequential indicator simulated models produced unrealistic heterogeneous architectural elements and overestimated the connectivity of net-reservoir elements. The multi-point statistical models realistically reproduced heterogeneous architectural elements geometries and the connectivity of net-reservoir elements. Study implications suggest that, based upon limited data, depositional conditioning can generate three dimensional training images to produce reservoir models that are both geologically realistic and reproducible. • Heterogeneity within the Lower Castlegate of Tuscher Canyon, Utah is characterised. • MPS, SIS and OBM models of fluvial reservoirs are compared. • MPS is found to produce the most realistic and reproducible results.