North-eastern Region Of Bangladesh Research Articles

Exploring the Effect of Rainfall Variability and Water Extent in Tanguar Haor, Sunamganj

Tanguar haor is located in the north-eastern region of Bangladesh and frequently experienced extreme events such as high rainfall that affect the haor basin area with flash floods on a regular basis. Tanguar haor is usually foreseen to severe disastrous conditions for the reason of changes in rainfall patterns and water extent. The study was conducted at Tanguar haor of Sunamganj district. This study mainly focuses on the year to year rainfall variability (2001-2018) and water extent (2002-2018) in the Tanguar haor area. The specific objective of the study was to explore the effect of rainfall variability and water extent in Tanguar haor. Information and data were collected mainly from secondary sources. Analysis of data and assess the ecological effect of changes in rainfall patterns and water extent were the main activities of the study along with others. The findings of the study were changeability in rainfall patterns and water extent frequently caused a flash flood in pre-monsoon and monsoon season in the Tanguar haor area. Flash flood causes a vast amount of financial loss for the living people of the Tanguar haor that makes them more vulnerable to live well. The result of this study may help to gather new knowledge on the consequences of rainfall variability and water extent in the haor basin area. It may add significance to the management of flash flood and severe stress in the haor basin area.

GROUNDWATER VULNERABILITY ASSESSMENT OF SYLHET SADAR USING GIS

Groundwater has been treated as a vital water supply because of its comparatively low vulnerability to pollution compared to surface water. Due to the health and economic impacts of groundwater contamination, steps to measure groundwater vulnerability are necessary for sustainable groundwater protection and management planning. In this study, an attempt has been made to assess groundwater vulnerability using the overlay index method and to prepare a groundwater vulnerability map using Geographic Information System (GIS) of Sylhet Sadar, a northeastern region of Bangladesh. Also, for the water depth-wise vulnerability assessment, the Water index was generated to observe the effect on chemical concentration for the depth of water. By assigning weight to each pollutant map in the overlay index approach, a combined hazard map was successfully created. The combined hazard map shows a total of 16.04%, 41.36%, and 42.59% of the studied area located in a less, moderate, and severely vulnerable zone, respectively. The combined effect of the chemical concentrations of water gradually decreases with the increase in water depth. Therefore, the developed map can be used as a tool for the management to take initiatives for sustainable use of groundwater.

GROUNDWATER VULNERABILITY ASSESSMENT OF SYLHET SADAR USING GIS

Groundwater has been treated as a vital water supply because of its comparatively low vulnerability to pollution compared to surface water. Due to the health and economic impacts of groundwater contamination, steps to measure groundwater vulnerability are necessary for sustainable groundwater protection and management planning. In this study, an attempt has been made to assess groundwater vulnerability using the overlay index method and to prepare a groundwater vulnerability map using Geographic Information System (GIS) of Sylhet Sadar, a northeastern region of Bangladesh. Also, for the water depth-wise vulnerability assessment, the Water index was generated to observe the effect on chemical concentration for the depth of water. By assigning weight to each pollutant map in the overlay index approach, a combined hazard map was successfully created. The combined hazard map shows a total of 16.04%, 41.36%, and 42.59% of the studied area located in a less, moderate, and severely vulnerable zone, respectively. The combined effect of the chemical concentrations of water gradually decreases with the increase in water depth. Therefore, the developed map can be used as a tool for the management to take initiatives for sustainable use of groundwater.

Analyzing Livelihood Sustainability of Climate Vulnerable Fishers: Insight from Bangladesh

Fish and fishery resources play an important role in improving socio-economic status of the fishing communities. Sylhet, the haor (bowl or saucer shape shallow depression) dominated administrative divisions (encompassing RAMSAR site and Ecological Critical Wetland Area) of Bangladesh is very promising for freshwater capture fisheries. But very few studies focused on the overall status on livelihood sustainability of fishing communities in this region. This study identified the demography, livelihood strategy, constraints of fishing and their coping strategies, strength, weakness and opportunity of fishing communities using household questionnaires, oral history interviews, and focus group discussions in Sylhet division (north eastern region of Bangladesh). The study identified physical strength and intention to work all the year round as the key strengths and acute poverty, poor economy, lack of alternative income generating opportunity and reduced fish availability as common weakness of fishers. Major threats facing by the fishers were natural calamities, overexploitation, dependency on natural resources and improper policy implication. Scope of alternative income generating opportunities, training and motivational program among the resource users and community based fisheries management could improve the situation. Findings of this study would provide important guideline for wetland management, planning and development of livelihood sustainability of the fishing communities.

Status of formalin in commercially important fishes from the northeastern region of Bangladesh

The study revealed the status of formalin used in four commercially important fishes namely Rohu (Labeo rohita), Catla (Catla catla), Mrigal (Cirrhinus cirrhosus) and Hilsa (Tenualosa ilisha) from Sylhet and Moulvibazar district for a period of four months from April to July 2016. A total of 100 fish samples from different town and village markets were collected and analyzed instantly on the market to detect the presence of formalin by using a kit developed by Bangladesh Council of Scientific and Industrial Research (BCSIR). Among the analyzed fishes 46.7, 26.7, 20.0 and 13.3% of Rohu, Catla, Mrigal and Hilsa, respectively were found treated with formalin from Sylhet district. Similarly, formalin was also detected in 40, 20, 20 and 20% of investigated Rohu, Catla, Mrigal and Hilsa from Moulvibazar district, individually. There was no significant difference in formalin used between town and village market, whereas a significant difference in application of formalin in domestic and imported fishes except Catla has been identified. Two-third of imported Rohu (66.7%) was found formalin positive followed by Hilsa (44.4%), Mrigal (40%) and Catla (35.7%). Amongst the domestic fishes, presence of formalin was detected in 27.8, 18.8, 10.0 and 4.8% in Rohu, Catla, Mrigal and Hilsa, separately. This devastating use of formalin in food fishes should be banned through proper enactment of the existing laws of the country, as well as timely and appropriate implementation of government monitoring is mandatory to combat the unethical formalin use.

Decision Making Capacity and Constraints Faced by Rural Women while Seeking Maternal and Child Health Care Services in Northeastern Bangladesh

The aim of the study was to determine the association between rural women’s decision-making power and the constraints faced by them while seeking Maternal and Child Health care services in northeastern Bangladesh. The study sample consisted of 150 mothers living in northeastern Bangladesh who had accessed institutional MCH care services during their pregnancy, childbirth and the postpartum period. Data were collected through a structured questionnaire using simple random sampling technique from January-April, 2018 and analyzed using descriptive statistics, decision making index and constraints facing indexing method through SPSS and Microsoft Excel. The study results showed that, decisions about treatment-seeking, consultation with the doctor during the prenatal and postnatal period, institutional birth preference and use/not use of contraceptives was always taken by the husband because the index was closer to the weighted value 200. But while making decisions about purchasing household daily needs, medicines, taking the first child or having more than two children, both husband and wife participated equally. On the other hands, constraint facing index showed that lack of medicine and vaccination, unhealthy environment and unprofessional behavior of the clinic’s people with CFI 651, 316 and 304 respectively, were the most commonly faced constraints by the rural women which discouraged them to seek institutional MCH care services. Though rural women were not completely suppressed in the northeastern region of Bangladesh, healthcare-seeking decisions were completely under the supervision of the men of families. Along with the socio-economic barriers, unprofessionalism, unavailability and mismanagement of the offered services also discouraged them to access institutional MCH care services. Awareness building among the rural people, especially in the recipients of this service along with Government and policy maker’s intervention to ensure a better quality of MCH care services can change the scenario of MCH care-seeking attitude of rural women in northeastern Bangladesh.

Electrical resistivity survey in the investigation of hydrogeological condition of Sylhet-Sunamganj Haor area, Bangladesh

Bangladesh depends on the ground water resources to meet domestic and agricultural demands. Electrical Resistivity Sounding survey, borehole litho logs and the water quality data of the area have been analysed for the assessment of subsurface hydro geological condition of the study area, located in north eastern region of Bangladesh. Hydro geological data are needed to determine the basic parameters required for the characterization of aquifer. VES can provide subsurface information related to groundwater condition in conjunction with borehole and water quality information. Resistivity soundings were carried out to establish the characteristics of the aquifer in the study area. Results of resistivity soundings and borehole data reveal that the subsurface formations are made up of clay, silty clay, clayey sand, fine, medium and coarse sands. The hydro stratigraphic unit of the study area comprises of three aquifer systems separated by aquitards. Aquifer-1 known as shallow aquifer, shows thickness in the range from 4 m to 104 m. Maximum thickness of Aquifer-1 is about 104 m at At para, Kishoreganj and minimum thickness is about 4 m at Madan, Netrokona. Aquifer-2 shows thickness variation from 3 m to 135 m. Maximum thickness of Aquifer-2 is about 135 m at Madhabpur, Habiganj and minimum thickness is about 3 m at Bajitpur, Kishoreganj. Baseof Aquifer-3, the deep aquifer could not be identified. Maximum depth of the upper boundary of this unit is about 171 m at Madhabpur,Habiganj and minimum depth is about 100 m at Mohanganj, Netrokona. At Madan, Netrokona low resistivity value of about 7 ohm below 107 m depth is found against a fine to medium sand layer suggesting saline formation water.

Wetland resource governance in Bangladesh: An analysis of community-based co-management approach

Wetland resource governance is a critical issue in Bangladesh, where the rural communities depend on natural resources and cause over-exploitation of natural resources. Purposive exploitation of wetland resources in Bangladesh is a result of the top-down approach. In response to centralized resources management system, community-based co-management emerged mainly to ensure the sustainability of natural resources through benefiting the local communities. Based on our study in Tanguar Haor, a unique wetland ecosystem in the northeastern region of Bangladesh, co-management approach can promote greater participation of the local community in resource management but establishing such governance arrangements take time depending on the potential of community organizations. As the study revealed, the Initiative of establishing co-management is still a challenge in Tanguar Haor, where there is a high dependency on resources given the socio-economic conditions. Also, the ineffectiveness of the existing community organization, largely due to a lack of leadership at the local level, is an obstacle to governing this wetland. Therefore, the findings of this study broadly highlight the necessity for strengthening the community organization through a collaborative process. In line with the commitment of government as well as its realization at the community level, the need for responsible, legitimate and effective roles of the community people including leaders has been further urged towards sustainable management of the wetland resources.

Remote Sensing-Based Quantification of the Impact of Flash Flooding on the Rice Production: A Case Study over Northeastern Bangladesh.

The northeastern region of Bangladesh often experiences flash flooding during the pre-harvesting period of the boro rice crop, which is the major cereal crop in the country. In this study, our objective was to delineate the impact of the 2017 flash flood (that initiated on 27 March 2017) on boro rice using multi-temporal Landsat-8 OLI and MODIS data. Initially, we opted to use Landsat-8 OLI data for mapping the damages; however, during and after the flooding event the acquisition of cloud free images were challenging. Thus, we used this data to map the cultivated boro rice acreage considering the planting to mature stages of the crop. Also, in order to map the extent of the damaged boro area, we utilized MODIS data as their 16-day composites provided cloud free information. Our results indicated that both the cultivated and damaged boro area estimates based on satellite data had strong relationships while compared to the ground-based estimates (i.e., r2 values approximately 0.92 for both cases, and RMSE of 18,374 and 9380 ha for cultivated and damaged areas, respectively). Finally, we believe that our study would be critical for planning and ensuring food security for the country.

Comparative Study of the Predictors of Socio Economic Status between Manipuri and Khasia Ethnic Communities in North Eastern Region of Bangladesh

Comparative Study of the Predictors of Socio Economic Status between Manipuri and Khasia Ethnic Communities in North Eastern Region of Bangladesh

Impacts of Tipaimukh Dam on the Down-stream Region in Bangladesh: A Study on Probable EIA

Amidst mounting protests both at home and in lower riparian Bangladesh, India is going ahead with the plan to construct its largest and most controversial 1500 mw hydroelectric dam project on the river Barak at Tipaimukh in the Indian state Manipur. In the process, however, little regard is being paid to the short and long-term consequences on the ecosystem, biodiversity or the local people in the river’s watershed and drainage of both upper and low reparian countries. This 390 m length and 162.8 m. high earthen-rock filled dam also has the potential to be one of the most destructive. In India too, people will have to suffer a lot for this mega project. The total area required for construction including submergence area is 30860 ha of which 20797 ha is forest land, 1195 ha is village land, 6160 ha is horticultural land, and 2525 ha is agricultural land. Cconstruction of the massive dam and regulate water flow of the river Barak will have long adverse effects on the river system of Surma and Kushiyara in the north-eastern region of Bangladesh which will obviously have negative impacts on ecology, environment, agriculture, bio-diversity, fisheries, socio-economy of Bangladesh. To assess the loss of Tipaimukh dam on downstream Bangladesh, an Eivironmental Impact Assessment (EIA) has been conducted based on probable affect parametes. Present study intends to depict Tipaimukh dam construction post scenerio in Bangladesh thru assessing probable loss and damage of the Tipaimukh dam construction. The most effective Batelle method of EIA has been applied in this study. It is found -5 scale severity impact will be imposed if the proposed dam is being construct after assessing values of each parameter. Journal of Science Foundation 2015;13(1):3-10DOI: http://dx.doi.org/10.3329/jsf.v13i1.27827

Climate change impacts and its implications on future water resource management in the Meghna Basin

Copious precipitation in the Meghna Basin has remarkable consequences for floods in the north-eastern region of Bangladesh. In addition, due to climate change more frequent extreme precipitation may also increase the frequency and intensity of flash floods. In this study, a hydrologic model H08 has been applied over the basin at a relatively fine grid resolution (10km). The impacts of climate change are assessed by using the super-high-resolution MRI-AGCM3.2S with A1B scenario through three time-slice experiments; the base-period (1979–2003), the near-future (2015–2039), and the far-future (2075–2099) periods. This study investigates the spatio-temporal changes and the changes in the frequency of precipitation and runoff with different magnitude ranges and finds the implications for water resources management under climate change. Results show that, (a) the projected maximum increment of mean annual precipitation (runoff) is +23% (+34%) and +31% (+39%) during the near-future and the far-future, respectively, (b) the projected increment of median value of monthly discharges at basin outlet is significantly high in wet period (May-July), ranging from 38 to 44% and 25–104% in the near-future and the far-future, respectively. Moreover, the monsoonal peaks are expected to come about 1∼1.5 month earlier, which ultimately lead to higher possibility of earlier flash flood in the future. This anticipated higher increment in peak discharge as well as future shifting of seasonal cycle of river discharge will have significant implications for agriculture and flood disaster management. Findings will also contribute to enhance water resource management in the basin and improve the design of adaptive measures.

The use of a flood index to characterise flooding in the north-eastern region of Bangladesh

Flooding in the Haor region in the north-east of Bangladesh is presented in this paper. A haor is a saucershaped depression, which is used during the dry period (Dec to mid-May) for agriculture and as a fishery during the wet period (Jun-Nov). Pre-monsoon flooding till mid-May causes agricultural loss. The area is bordering India, and is fed by some flashy Indian catchments. The area is drained mainly by the Surma-Kushiyara river system. The terrain generally is flat and the flashy characteristics die out within a short distance from the border. Limited studies on the region, particularly with the help of numerical models, have been carried out in the past. Therefore, an objective of the current research was to set up numerical models capable of reasonably emulating the physical system. Such models could, for example, associate different gauges to the spatio-temporal variation of hydrodynamic variables and help in carrying out a systemic study on the flood propagation. A 1D2D model, with one-dimensional model for the rivers (based on MIKE 11 from DHI) and a two-dimensional model for the haors (based on MIKE 21 from DHI) were developed. In order to characterize flooding in the large area a flood index is proposed, which is computed based on the hydrograph characteristics such as the rising curve gradient, flood magnitude ratio and time to peak. The index was used in characterising flooding in the Haor region. In general, two groups of rivers were identified. The study enabled identifying the hot-spots in the study area with risks from flooding.

Notes On Two Lycaenid Butterflies Confirm To Bangladesh

The present article confirms that two new butterflies (Lepidoptera: Lycanidae) species, Logania distanti massalia Doherty, 1891 (Dark Mottle) and Nacaduba pactolus continentalis Fruhstorfer, 1916 (Large four-Linblue) reported for the first time from the North-eastern region of Bangladesh during an opportunistic survey on butterflies. These two new sighting records signify previous sampling gaps and suggest further survey to make a baseline database and take effective initiatives for conservation to protect the butterfly fauna in this area.

Evaluation of Naga Chilli (Capsicum chinense Jacq.) genotypes for Various Horticultural Characters under North eastern region of Bangladesh

Evaluation of Naga Chilli (Capsicum chinense Jacq.) genotypes for Various Horticultural Characters under North eastern region of Bangladesh

Dragonflies and damselflies (Insecta: Odonata) of the northeastern region of Bangladesh with five new additions to the Odonata fauna of Bangladesh

Odonata were surveyed in one reserve forest, two national parks, one Eco Park, one lake and one University campus in the northeastern region of Bangladesh from March 2014 to March 2015. A total of 64 species of Anisoptera and Zygoptera belonging to 41 genera under seven families were recorded. Among them 45 species and 19 genera were new records for the study area. Two species of Anisoptera, i.e., Anax indicus Lieftinck, 1942 and Gynacantha khasiaca MacLachlan, 1896, and three species of Zygoptera i.e., Matrona nigripectus Selys, 1879, Agriocnemis kalinga Nair & Subramanian, 2014, and Prodasineura laidlawii Forster, 1907 were recorded for the first time from Bangladesh.

Allometric Modeling for Leaf Area and Leaf Biomass Estimation of Swietenia mahagoni in the North-eastern Region of Bangladesh

Leaf area (<TEX>$A_0$</TEX>) and leaf biomass (<TEX>$M_0$</TEX>) estimation are significant prerequisites to studying tree physiological processes and modeling in the forest ecosystem. The objective of this study was to develop allometric models for estimating <TEX>$A_0$</TEX> and <TEX>$M_0$</TEX> of Swietenia mahagoni L. from different tree parameters such as DBH and tree height of mahogany plantations in the northeastern region of Bangladesh. A total of 850 healthy and well formed trees were selected randomly for sampling in the five study sites. Then, twenty two models were developed based on different statistical criteria that propose reliable and accurate models for estimating the <TEX>$A_0$</TEX> and <TEX>$M_0$</TEX> using non-destructive measurements. The results exposed that model iv and xv were selected on a single predictor of DBH and showed more statistically accuracy than other models. The selected models were also validated with an additional test data set on the basis of linear regression and t-test for mean difference between observed and predicted values. After that, a comparison between the best logarithmic and non-linear allometric model shows that the non-linear model produces systematic biases and underestimates <TEX>$A_0$</TEX> and <TEX>$M_0$</TEX> for larger trees. As a result, it showed that the bias-corrected logarithmic model iv and xv can be used to help quantify forest structure and functions, particularly valuable in future research for estimating <TEX>$A_0$</TEX> and <TEX>$M_0$</TEX> of S. mahagoni in this region.

Food, Nutrition and Health Care: diverse conceptions amongst adolescent population in a semi-urban Bangladeshi Muslim community

Objective: This study explores how the adolescents identify diet and why do they select these types of foods as diet and how they conceptualize health. Methodology: This is an empirical study conducted applying qualitative methods in a semi-urban Muslim community at Sylhet district in the northeastern region of Bangladesh. Data were collected through in-depth interviews. Results: Adolescents had diverse conceptions on foods related to nutrition and health care. Adolescents relate food categorization mainly with the price of food, function of foods and a number of sensory characteristics, such as taste, smell and color. They categorized foods according to the price of foods- poor and rich; and to the function of foods- hot and cold. They had different preferences in different genders according to the sensory characteristics of foods- black color, sour taste etc. They had also some gender specific taboo on some foods. Conclusion: This study reveals that adolescents have diversified thinking on foods related to nutrition and health care practices, which demands to provide special attention for improving their understanding on food, nutrition and health care. DOI: http://dx.doi.org/10.3329/bjms.v13i4.19165 Bangladesh Journal of Medical Science Vol.13(4) 2014 p.391-395

Changes of rainfall extremes around the haor basin areas of Bangladesh using multi-member ensemble RCM

Haors are large, round-shaped floodplain depressions located in the North-Eastern region of Bangladesh. Extreme events such as heavy rainfall routinely affect the haor basin with flash floods. These haors are predicted to experience severe stress because of changes in rainfall and temperature patterns. The biotic community of the wetlands may not have enough time to adjust itself in such varying temperature and rainfall extremes. This paper evaluates various aspects of the future projections of rainfall and temperature extremes, including magnitudes and frequencies thereof. The impacts of extreme events are examined using Hadley Centre’s high-resolution regional climate model known as PRECIS (Providing REgional Climates for Impact Studies). Daily temperature and rainfall simulations of the 17-member ensembles are generated through Hadley Centre Coupled Model (HadCM3). These simulations are used in Rclimdex—a software specially designed for this study. A total of 12 core climate indices are computed, analyzed, and statistically examined (Mann–Whitney U test) over the space of three time slices—(1) short (2020s, i.e., 2011–2040), (2) medium (2050s, i.e., 2041–2070), and (3) long (2080s, i.e., 2071–2098). Here, the 1980s (1971–2000) are considered as the baseline period. The study has found that the highest significant variability in both rainfalls and temperatures was during the pre-monsoon season when flash floods normally occur. Also, rainy days are projected to be less frequent albeit more intense where the deeply flooded haors are located. Though the annual total rainfall does not show any difference in spatial distribution (except for in magnitude), the seasonal patterns of most extreme events show that the probable affected areas have shifted from North-east to further North. In addition, a significant increase in both RX1 (1-day maximum rainfall) and RX5 (5-day maximum rainfall) are projected during the 2080’s pre-monsoon season near Sunamganj. This projection also indicates the possible frequent occurrence of flash floods with high volumes. Probability distribution frequencies (PDF) show a rightward shift in time indicating an increase in the amount of total rainfall in the future. Exceptions are, however, found in case of PDFs for consecutive dry days (CDD) and consecutive wet days (CWD). The decrease in CWD is found to be more pronounced than that of CDD. All these projections made in this study are expected to contribute further in the advancements of the Master Planning of the haor area that was done by the government of Bangladesh in 2012.

Do environmental attributes, disturbances and protection regimes determine the distribution of exotic plant species in Bangladesh forest ecosystem?

Introduction of exotic plant species in the tropics has occurred since the colonial period, and has mostly been for timber production. However, due to uncontrolled distribution and lack of awareness, many of these species became invasive, and have been increasingly reported as a source of threats to native ecosystems. We investigated the exotic species richness, their traits, and biogeographic origin in the Satchari Forest in the north-eastern region of Bangladesh, one of the very few intact terrestrial ecosystems remaining in the country. Boosted Regression Trees and Detrended Correspondence Analysis were performed to determine the contribution of various environmental attributes, protection regimes, and disturbances to explain the distribution of exotic species within Satchari Forest. Among the environmental variables, native species richness, elevation gradient, and soil nutrient parameters were found as good predictors of both exotic species’ presence and richness in the area. In our analysis, number of exotic species showed a unimodal relationship with native species in the reserved forest, where the relationship was negative in the surrounding area. An increase in exotic species with the presence of higher anthropogenic disturbance events, thereby with lower conservation restrictions as well as with lower protection status, was also evident. Our study suggests that enforcing greater protection status and preventing human use can be the best ways to protect native species composition in forest ecosystems with greater conservation values in tropical developing countries.