Southwestern Coastal Region Of Bangladesh Research Articles

Antioxidant potentials of Acanthus ilicifolius leaves from Southwest Coastal Region of Bangladesh

This research delves into the antioxidant potential of Acanthus ilicifolius leaves harvested from the southwestern coastal region of Bangladesh. Four distinct solvents—methanol, ethanol, acetone, and ethyl acetate—were utilized to determine antioxidant activities. Initial phytochemical screening unveiled the existence of many secondary metabolites, including as flavonoids, phenols, alkaloids, and others. Total phenolic content, total flavonoid content, and total proanthocyanidin content were determined using quantitative analysis. The assessment of antioxidant activity was conducted using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging assays. Notably, the acetone extract of Acanthus ilicifolius exhibited the highest total phenolic content (24.75 mg of GA/g), total flavonoid content (12.9 mg of catechin/g), and total proanthocyanidins content (11.47 mg of catechin/g). The ethanol extract displayed the most robust antioxidant activity in both DPPH (91.41 %) and ABTS (66.78 %) scavenging assays among the crude extracts, underscoring its potential as a valuable source of antioxidants. The results emphasise the crucial importance of choosing the appropriate solvent in the extraction procedure and suggest that Acanthus ilicifolius leaves, particularly when extracted with ethanol, acetone, or methanol, hold promise as a natural source of antioxidants. This study offers valuable insights into the bioactive potential of Acanthus ilicifolius leaves.

Risk Perceptions and Vulnerability Assessment: Induced from Tropical Cyclone in the Southern Part of Coastal Bangladesh

The coastal area that borders Bangladesh is extremely vulnerable to natural disasters like tropical cyclones, which cause the majority of the damage and fatalities related to flooding. This study attempts to evaluate the susceptibility of coastal flooding induced by tropical cyclones in the South-Western coastal region of Bangladesh. It also identifies the relationship between the influencing factors and respondents' perceptions of risk in terms of socio-economic characteristics. Data was gathered by using a standardized interview schedule from coastal households of three districts named as South Khali (Bagerhat), Padma Pukur (Satkhira), and Rangopaldi (Patuakhali). The survey was taken through interview to assemble information on risk perception, also explores the impact of flood risk on agriculture, environment and livelihood sectors to describe the most specific vulnerable one of different regions that provides a robust insight of affected residents. Moreover, twenty-one predominant factors in terms of three components reveal a strong relationship with severity to flood risk. Results also indicate that, vulnerability indexes differ significantly (p value < 0.05) in the study areas (vulnerability index = 0.54 in South Khali, 0.77 in Padma Pukur, and 0.74 in Rangopaldi). In addition, disaster vulnerability index differs with different socio-economic and geographical factors which enhance the negative effect of flood for the coastal community. The study also reveals that, the selected area had no adequate dam and embankment, cyclone shelter as well as material support from the government and non-government organization which makes their life risky to flood. The research recommends that, generating different livelihood options, self-organization by different disaster preparedness training program to enhance their resilience, indigenous and disaster risk reduction strategies, build more coastal flood shelters and restore people’s livelihoods by supplying agricultural seeds, livestock, poultry etc. significantly minimize the vulnerability of the affected community.

Strengthening adaptation in coastal Bangladesh: community-based approaches for sustainable agriculture and water management

The coastal region of Bangladesh is significantly influenced by soil and water salinity, which is further exacerbated by the increasing frequency of tropical cyclones and rising sea levels. Understanding the extent of salinity and its challenges is crucial for promoting sustainable agriculture and ensuring access to safe drinking water. Using quantitative (soil and water parameters) and qualitative (focus group discussion and key informant interview) data, we investigated (i) soil and water salinity and soil nutrient contents; and (ii) adaptive practices in agriculture and drinking water management in three sub-districts (Assasuni, Dacope and Morrelganj) in the southwestern coastal region of Bangladesh. Results show that soil salinity levels did not significantly differ among the sub-districts, with Assasuni having slightly higher soil salinity (8.24 dS m-1) compared to Dacope (8.08 dS m-1) and Morrelganj (7.96 dS m-1). Significant differences were observed in the salinity level of pond and canal water among the sub-districts, with Assasuni having the highest levels of salinity in both pond (13.98 dS m-1) and canal water (77.85 dS m-1), compared to other sub-districts. Soil and water salinity were the major challenges reported by the respondents; however, climate-induced stresses (e.g., untimely precipitation) and outbreaks of pests during droughts have been identified as prominent issues in sustainable agriculture. Rainwater harvesting has been identified as a viable adaptive technique in drinking water management, offering a feasible solution to address water and soil salinity. The study underscores the importance of implementing adaptive practices (e.g., rainwater harvesting) to address water scarcity and salinity issues in the coastal region and promote resilient agricultural systems.

Coastal Flood Induced Salinity Intrusion Risk Assessment Using a Spatial Multi-criteria Approach in the South-Western Bangladesh

AbstractBangladesh is extremely vulnerable to sea-level rise and other climate-induced extreme events, such as flooding, storm surge, and salinity intrusion. The south-western coastal region of Bangladesh is particularly vulnerable to salinity intrusion caused by cyclone induced storm surges and coastal floods. Salinity intrusion endanger land productivity by increasing both soil and surface water salinity. Detailed risk assessment using spatial mapping approach can contribute to mitigating the effects of salinity intrusion on natural capital and the environment. In this study, we established and evaluated a spatial multi-criteria approach for mapping the risk levels of areas to salinity intrusion impacts using field data and geospatial techniques at the local scale. We evaluated the viability of the proposed approach using Khulna District, a major coastal city and saline prone area in the south-western Bangladesh. We considered three risk components (i.e. vulnerability, exposure and hazard) with 16 relevant criteria for the study. For each criterion, an Analytical Hierarchy Process (AHP) was used to build and weight spatial raster map layers. Individual maps for each risk component were generated using a weighted sum technique, and lastly, a risk map was created by combining those. Our generated maps correctly identified relevant spatial dimensions as well as risk levels (i.e. very-high to very-low). The outcomes of our study suggest that the southern (east and west) parts of the study area are mostly susceptible to salinity intrusion due to higher storm surge impacts, lower elevation, and land use patterns than other parts. We validate our findings using a qualitative and quantitative approach. We believe that this novel approach would be useful to create risk maps that policymakers and relevant stakeholders could potentially use to evaluate risks posed by flood induced salinity intrusion in coastal regions of Bangladesh and elsewhere with similar geo-climatic context.

Decision support system for community managed rainwater harvesting: A case study in the salinity-prone coastal region of Bangladesh

Climate change-induced saline intrusion into both surface and groundwater, extreme weather events, and unregulated water usage are serious threats to the drinking water supply in coastal areas worldwide, especially in least-developed countries. This research developed a data-driven decision-making methodology to evaluate the performance of rainwater harvesting (RWH) systems in the saline-prone southwestern coastal region of Bangladesh. Twenty-five community managed RWH systems, recently piloted in two major coastal districts, were considered the case study to develop and validate this evaluation tool. The evaluation methodology integrates daily water models, lifetime cost analysis, Geographic Information System (GIS)-based parameters supported by the Analytical Hierarchy Process (AHP), and field observation. While the meteorological parameters as well as the hydrological and economic performance were found to be highly suitable, 36 % of the systems showed moderate performance, as challenges remain in ensuring proper operation and maintenance practices at the community level. However, 40 % of the systems showed high performance, with two systems showing very high suitability, which suggests community managed RWH systems as a sustainable adaptation for coastal water supply.

HOUSEHOLDS’ WILLINGNESS TO PAY FOR NATURAL HAZARD INSURANCE IN THE SOUTHWESTERN COASTAL REGION OF BANGLADESH

The southwestern coastal region of Bangladesh is enormously susceptible to natural hazards due to global environmental change, triggering economic instability in coastal households every year. Hazard microinsurance might be a decent option to build financial resilience; considering the assorted consumers’ preferences is essential for policy scheming. Therefore, this research estimated households’ willingness to pay (WTP) for natural hazard insurance (NHI) in Bagerhat Sadar and Rampal upazila of Bagerhat district in southwestern coastal Bangladesh. The contingent valuation method’s double-bounded dichotomous choice (DBDC) technique was exerted on the 120 randomly interviewed households’ dataset to estimate the WTP for NHI considering three experimental bid values (i.e., initial bid of BDT 300, maximum bid of BDT 500, and lower bid of BDT 200 as the NHI premium per month). This assessment revealed that, on average, around three-fourth of coastal household experienced financial losses (i.e., damage to crops, fish-shrimp enclosures, integrated farms, and houses) yearly due to natural hazards. Almost two-third of the total sample was interested in taking such alternative financial support after a massive coastal hazard, and the mean WTP was approximately BDT 284. Amongst those households, more than four-fifth were willing to pay for the initial bid value. Moreover, a logit analysis was performed to identify WTP’s probability and maximum likelihood; the Pearson goodness-of-fit test to estimate the chi-square ( =5.29; p<0.01) value; and Kendall’s tau-b ( ) test to clarify the level of significance and associations [Highest correlation-coefficient (WTP and initial bid) =0.837**; **p<0.01; strongly associated; optimal value] between WTP and three experimental bid values. Besides, this research has attempted to give policymakers a vivid understanding of households’ behavior in adopting such microinsurance. Government and development agencies are highly recommended to implement such a microinsurance scheme as post-hazard economic facilitation for coastal victims.

Coupling of machine learning and remote sensing for soil salinity mapping in coastal area of Bangladesh

Soil salinity is a pressing issue for sustainable food security in coastal regions. However, the coupling of machine learning and remote sensing was seldom employed for soil salinity mapping in the coastal areas of Bangladesh. The research aims to estimate the soil salinity level in a southwestern coastal region of Bangladesh. Using the Landsat OLI images, 13 soil salinity indicators were calculated, and 241 samples of soil salinity data were collected from a secondary source. This study applied three distinct machine learning models (namely, random forest, bagging with random forest, and artificial neural network) to estimate soil salinity. The best model was subsequently used to categorize soil salinity zones into five distinct groups. According to the findings, the artificial neural network model has the highest area under the curve (0.921), indicating that it has the most potential to predict and detect soil salinity zones. The high soil salinity zone covers an area of 977.94 km2 or roughly 413.51% of the total study area. According to additional data, a moderate soil salinity zone (686.92 km2) covers 30.56% of Satkhira, while a low soil salinity zone (582.73 km2) covers 25.93% of the area. Since increased soil salinity adversely affects human health, agricultural production, etc., the study's findings will be an effective tool for policymakers in integrated coastal zone management in the southwestern coastal area of Bangladesh.

Salinity hazard drives the alteration of occupation, land use and ecosystem service in the coastal areas: Evidence from the south-western coastal region of Bangladesh

Understanding the salinity effects on the rural livelihood and ecosystems services are essential for policy implications and mitigations. Salinity-driven modulation in land use and land cover, community traditional occupations, and ecosystem service have been elucidated in the present investigation. The study was carried out in the south-western region of Bangladesh as a representative case using focus group discussions, questionnaire survey, and remote sensing techniques. The findings showed that salinity-induced land use changes seriously threatened ecosystem services, employment and livelihoods. Shrimp farming was found to have replaced the majority of agricultural and bare lands, which led to the poor locals losing their land. The increasing land transformation to shrimp ponds as a coping strategy with salinity was not reported to be a viable option as maximum marginal poor people were unable to run the capital-intensive shrimp aquaculture. Eventually, many rich people occupied the cropland for shrimp farming which forced the traditional farmers and fishermen to leave their job and sell their labor. Many of the traditional services derived from the ecosystems were drastically reduced or got lost. The ultimate effect on the traditional livelihoods of the communities increased vulnerability and reduced resilience. The findings could aid in formulating realistic policies and action for ensuring the future resilience of the community through an appropriate adaptation strategy, such as introducing salinity-tolerant crops and integrated farming to safeguard the interest of the poor farmers. Despite the geographical locality of the study, its implications are global given the identical salinity concerns in other emerging nations' coastal regions.

Do Socio-demographic Factors Influence Water-fetching Practices? Evidence from the Southwestern Coastal Region of Bangladesh

The United Nations Sustainable Development Goal 6 aims to provide equitable access to safe and affordable water services. Yet, the lack of potable water in Bangladesh’s coastal region is a significant barrier to attaining this target. This study examines how socio-demographic factors influence water-fetching practices in coastal Bangladesh. Using a self-administered questionnaire, we surveyed 371 people from three vulnerable sub-districts, and the Chi-square test and a Multinomial Logistic Regression were utilized to explore significant factors affecting water-fetching practices. Findings show that water-fetching is typically considered a woman’s responsibility. Although three-quarters of the respondents stated that women usually collect water at home, most believe they should not be the only household member responsible for this task. Despite many initiatives, women are still left behind, resulting in inequities and gender injustices in their homes and society. Nonetheless, this study unfolds that water-fetching practices are biased and influenced by social and gender roles, where intensive attention is needed.

The Changing Climate Is Changing Safe Drinking Water, Impacting Health: A Case in the Southwestern Coastal Region of Bangladesh (SWCRB)

This study focuses on investigating the impact of climate change on the availability of safe drinking water and human health in the Southwest Coastal Region of Bangladesh (SWCRB). Additionally, it explores local adaptation approaches aimed at addressing these challenges. The research employed a combination of qualitative and quantitative methods to gather data. Qualitative data were collected through various means such as case studies, workshops, focus group discussions (FGDs), interviews, and key informant interviews (KIIs). The study specifically collected qualitative data from 12 unions in the Shyamnagar Upazila. On the other hand, through the quantitative method, we collected respondents’ answers through a closed-ended questionnaire survey from 320 respondents from nine unions in the first phase of this study. In the next phase, we also collected data from the three most vulnerable unions of Shyamnagar Upazila, namely Poddo Pukur, Gabura, and Burigoalini, where 1579 respondents answered questions regarding safe drinking water and health conditions due to climate change. The findings of the study indicate that local communities in the region acknowledge the significant impact of sea-level rise (SLR) on freshwater sources and overall well-being, primarily due to increased salinity. Over 70% of the respondents identified gastrointestinal issues, hypertension, diarrhea, malnutrition, and skin diseases as major waterborne health risks arising from salinity and lack of access to safe water. Among the vulnerable groups, women and children were found to be particularly susceptible to waterborne diseases related to salinity. While the study highlights the presence of certain adaptation measures against health-related problems, such as community clinics and health centers at the upazila level, as well as seeking healthcare from local and paramedical doctors, it notes that these measures are insufficient. In terms of safe drinking water, communities have adopted various adaptation strategies, including pond excavation to remove saline water (partially making it potable), implementing pond sand filters, rainwater harvesting, and obtaining potable water from alternative sources. However, these efforts alone do not fully address the challenges associated with ensuring safe drinking water.

Human exposures to multiple water sources in the southwestern coastal region of Bangladesh: water quality, pollution sources, and preliminary health risks appraisals.

The coastal areas of Bangladesh have poor accessibility to fresh drinking water and the groundwater is not suitable for drinking, cooking, and other domestic uses due to high levels of salinity and potentially toxic elements. The current study focuses on understanding of the distribution of some physicochemical parameters (temperature, pH, EC, TDS, and salinity) and chemical elements (Fe, Mn, Zn, Ca, Mg, Na, K, Cu, Co, Pb, As, Cr, Cd, and Ni) with health perspective in drinking water from the southwestern coastal area of Bangladesh. The physicochemical properties of the water samples were examined with a multiparameter meter, while the elemental concentrations were analyzed using atomic absorption spectrometer. Water quality index (WQI) and irrigation indices were utilized to determine the drinking water quality and irrigation feasibility, respectively, whereas hazard quotients (HQs) and hazard index (HI) were used to assess the probable pathways and the associated potential risks to human health. The concentrations of some toxic elements in measured samples were relatively higher compared to drinking water guidelines, indicating that ground and surface water are not apt for drinking and/or domestic uses. The multivariate statistical approaches linked the source of the pollutants in the studied water body mostly to the geogenic origin including saline water intrusion. WQI values ranged from 18 to 430, reflecting excellent to unsuitable categories of water quality. The assessment of human health risks due to exposure to contaminated water demonstrated both carcinogenic and non-carcinogenic health risks in the exposed residents of the study area. Therefore, appropriate long-term coastal area management strategies should be adopted in the study region for environmental sustainability. The findings of this research will be supportive in understanding the actual situation of fresh drinking water in the area for policymakers, planners, and environmentalists to take effective necessary measures to ensure safe drinking water in the study area.

Fishermen’s competitiveness and labour market performance: Evidence from shrimpers in Bangladesh

AbstractWe conduct an experiment to determine competitiveness among shrimpers who engage in collecting shrimp seeds in the southwestern coastal region of Bangladesh. We then examine how competitiveness affects the labour supply decisions and labour market performance of these shrimpers. Our results show that shrimpers who prefer competition are more productive than shrimpers who do not prefer competition. Competitive shrimpers secure better prices and earn higher incomes selling their catches. We estimate that their wage elasticity of participation ranges from 0.4 to 0.5, which is consistent with preferences under neoclassical assumptions. Competitive shrimpers have a slightly greater wage elasticity than non‐competitive shrimpers, suggesting that they might be more responsive to expected earnings. Our results have important policy implications for the efficient management of common pool resources.

Local Context of Climate Change Adaptation in the South-Western Coastal Region of Bangladesh

This study was conducted in 12 unions of the Shyamnagar upazila in the Shatkira District, located in the south-western coastal region of Bangladesh (SWCRB). The inhabitants of the SWCRB are affected by different climate-influenced events such as high-intensity cyclones, saltwater intrusion, sea-level rise, and weather pattern-affected agriculture. This study focused on how the local inhabitants are coping with climate change using multilevel adaptation. A mixed approach of data collection, including quantitative and qualitative data, was followed for both primary and secondary sources. Individual-level data collection, key informant interviews, close-ended questions, focus groups, life history of SWCRB residents, and workshops were used to understand vulnerability and social perceptions at the local level. The findings indicated that multiple adaptation practices are employed by people in the SWCRB, such as rainwater harvesting, plantation of different rice varieties, gardening of indigenous vegetables, and pond sand filtering. However, the construction of multipurpose cyclone shelters along with coastal afforestation contributes to building resilience in the SWRCB from the socio-economic and environmental perspectives. Therefore, this study will help to find the most adequate strategy for climate change adaptation and sustainability.

The impact of mangroves in small-holder shrimp ponds in south-west Bangladesh on productivity and economic and environmental resilience

Aquaculture production in extensive shrimp ponds along mangrove coasts may be influenced by many factors such as pond size, pond management, species diversity of mangroves and aquaculture species used, as well as the position and abundance of mangroves in the ponds. A growing number of studies indicate the potential positive effects of mangrove presence on pond productivity. In this study we aimed to assess the influence of mangrove presence on pond production characteristics as observed in the south-western coastal region of Bangladesh where mangroves grow largely naturally in aquaculture ponds. Using structured interviews we quantified a large number of pond production parameters from mangrove-associated shrimp aquaculture in ponds with a wide range of mangrove coverage (0% - >50%) including total costs, revenues and net profits. The 435 ponds for which data were collected were distributed among 61 villages in four regional clusters. The regions differed significantly in terms of the species present, the total coverage of mangroves, and their position in and around the ponds. Mangrove presence in the ponds correlated strongly with pond productivity and farm profits. Mangrove presence was significantly associated with smaller ponds which had higher input costs and revenue per unit pond area than larger ponds but lower net profitability. Notwithstanding our large sample size, and contrary to our expectations, this study was not able to identify clear profit benefits of the association of mangroves with shrimp ponds. Among various possible explanations, we suggest that, as currently observed in Bangladesh, the presence of mangroves in aquaculture ponds yields little or at most sub-optimal financial benefits. Hence, our results seem to indicate that there is great scope for improving of mangrove-use in shrimp aquaculture. In that, one can expect the largest potential benefit of associating mangroves with shrimp culture in large ponds (“scale benefit”) in which mangroves are presently not being used. The great potential for mangroves to help boost pond productivity and bolster farm economic and environmental resilience clearly remains largely untapped. Our results suggest that further work is needed to help farmers better select appropriate mangrove species, the most suitable locations for planting mangroves and the best percentage of mangrove pond coverage to boost shrimp production. As our cross-sectional study only provides a baseline of mangrove association with shrimp ponds additional, properly controlled experiments following the “Before-after-control-impact (BACI)” design are also needed in order to be able to discern the true causal effects of mangroves on aquaculture production.

Factors affecting the performance of household rainwater harvesting systems in the south-western coastal region of Bangladesh

Abstract This study aims to evaluate the post-installation performance of household (HH) rainwater harvesting (RWH) systems in the southwestern coastal region of Bangladesh. A conceptual framework for evaluating the effectiveness of RWH systems was developed based on seven determinants. An application of multivariable logistic regression showed that family size, monthly income, the practice of tank and downpipe cleaning, and the organizations supporting the installation were the most significant parameters (p< 0.05) affecting the effectiveness of the RWH systems. A family size of 1–4 has higher odds of having a properly functioning system (adjusted odds ratio (AOR) = 28.3; 95% confidence interval (CI) = 4.8–167.7) than a family of 9 or more. The practice of tank cleaning once per year (AOR = 3.3; 95% CI = 1.2–9.1) and downpipe cleaning more than 3 times/year (AOR = 9.7; 95% CI = 1.5–62.5) had higher odds than HHs practicing no cleaning at all. RWH systems installed by institutions other than the Department of Public Health Engineering, and NGOs had higher odds (AOR = 22.0; 95% CI = 2.3–213.0) compared to systems installed on their own. This study provides clues to strengthening the existing RWHS intervention programs in the water-challenged regions of Bangladesh.

Outwelling of nutrients into the Pasur River estuary from the Sundarbans mangrove creeks

The Pasur River estuary (PRE), the largest estuary in the Sundarbans mangrove area, provides vital fishery resources and supports millions of livelihoods in the southwestern coastal region of Bangladesh. This study focused on the tidal and run-off effects on the outwelling of nutrients from the Sundarbans mangrove creeks to the PRE. Spatial and temporal variations of nutrient and chlorophyll-a concentrations were assessed by water sampling at 11 stations in the study area from January to December 2019. Dissolved inorganic nutrients and chlorophyll-a were analyzed by standard methods using a spectrophotometer. In the tidal mangrove creeks, dissolved inorganic nitrogen, phosphate, and silica concentrations were significantly higher (p < 0.05) during the spring tide than those during the neap tide, suggesting that these nutrients were flushed from the mangrove area by the inundation and tidal mixing of the spring tide. In general, chlorophyll-a (mean ± SD) concentrations in the PRE and the tidal mangrove creeks were 5.62 ± 1.30 μg/L and 9.03 ± 0.59 μg/L in the wet season, respectively. During the dry season, the chlorophyll-a decreased to 4.37 μg/L ± 0.68 and 4.94 ± 1.52 μg/L in the PRE and the tidal mangrove creek, respectively. The amount of nutrients outwelled from the mangrove creeks to the estuary was 1.53 ± 0.67 mg/L DIP, 0.001 ± 0.0004 mg/L DIN, and 1.38 ± 0.48 mg/L dissolved silica. DIP, silica, and chlorophyll-a concentrations were significantly higher (p < 0.05) during the spring tide compared to the neap tide, but salinity was not significantly (p > 0.05) different between the two tidal levels. This study showed that the mangrove creeks formed an important link in transporting nutrients from the mangrove forest to the estuary.

Exploring Gender and Climate Change Nexus, and Empowering Women in the South Western Coastal Region of Bangladesh for Adaptation and Mitigation

This study has been conducted to identify vulnerabilities and effects of climate change on women in 12 unions in Shyamnagar upazila in the Satkhira district in the Southwestern Coastal Region of Bangladesh (SWCRB). Climate vulnerability and gender inequality may increase due to climate change. Women may, thus, face specific conditions of vulnerability in society and daily livelihood. This paper focuses on investigating factors that influence women’s vulnerability from climate change, their adaptations, and the importance of women empowerment to reduce their inequality in SWCRB. This study also emphasizes gender inequality caused by climate change, and looks at accommodations for women to reduce hostile influences of climate change. From the 9 unions in SWCRB, a total of 320 household respondents were randomly selected to complete a questionnaire. The results of the statistical analysis showed that most of the survey’s perimeter has significant. Interviews, case studies, focus group discussions, workshops, and key informant interviews were also conducted from 12 unions, and it was found that climate change impacts men and women differently, with women being more vulnerable than men. Through case study this paper investigated the main factors influencing the vulnerability of women. In terms of empowerment women may also be well positioned to lead adaptation efforts alongside men, as this analysis represent that gender inequalities are leading by social norms. Women being more vulnerable both in short-term i.e., major natural disasters, cyclones, flood, and long-term i.e., sea level rise, salinity intrusion in water and soil, land erosion, droughts, climatic events, as they enhance gender inequalities. Further, gender inequality is seen in illiteracy, food shortages and poor health conditions, traditional norms, religious taboos, and patriarchy. Moreover, gender-based economic opportunities, women’s mobility, and income are changing, while household authority relations and gender-based socio-economic, cultural, and institutional constraints remain. This study examines the increased vulnerability of women in SWCRB to climate change, which can be mitigated through women empowerment; female involvement with environmentally friendly stoves, rural electrification and renewable energy development, microfinancing, and nakshikantha. (Nakshikantha is a special type of sewing art that is made by creating designs with different types of colored threads on plain stitches). Lastly, women may also lead adaptation efforts alongside men, make decisions, and promote their participation.

Does land use change, waterlogging, and salinity impact on sustainability of agriculture and food security? Evidence from southwestern coastal region of Bangladesh.

The United Nation's sustainable development goal is to achieve zero hunger by 2030 and achieve food security throughout the world. In this context, we analyze the anthropogenic factors such as land use and land cover change, waterlogging, and soil salinity which combinedly affecting the agricultural sustainability and threatening the food security in the southwestern region of Bangladesh. Landsat satellite images from 1991 to 2021 were used to detect the changes and identify how anthropogenic activities have altered the land cover and land use and impede the sustainability of agriculture. Terra MODIS vegetation indices from 2000 to 2020 were used to detect waterlogging. Soil salinity was measured from the soil samples and vegetation soil salinity index (VSSI) from Landsat images. Findings of the study revealed that agricultural lands have decreased because of an increase in shrimp farming. Waterlogging and soil salinity are increasing due to increased shrimp farms also for poor drainage infrastructure and human modification. The area of agricultural land in 2011 was 19,657.12 acres,12,750.14 acres, and 38,774.70 acres in Keshabpur, Abhaynagar, and Manirampur, which changed to 12,668.70 acres (-36%), 7151.27 acres (-44%), and 32,809.30 acres (-16%) in 2021. Our hotspot analysis reveals that very high vulnerability to waterlogging due to floods was highest in Manirampur (15,464.09 acres). Finally, we proposed a new framework called IDCEM designed for monitoring land-use change, salinity, and waterlogging in the interior coast, which will indirectly help to promote food security and help in achieving sustainable development goal.

Assessment of Household Rainwater Harvesting Systems in the Southwestern Coastal Region of Bangladesh: Existing Practices and Household Perception

This study aims to assess the post-installation rainwater management issues associated with household RWH systems in the southwestern coastal regions of Bangladesh. A face-to-face questionnaire survey (including free listing) was administered to over 300 households in the Khulna and Satkhira districts to understand the water consumption behavior of users, operation and maintenance of the RWH system components, governance and capacity-building needs, and overall perception. It was found that the current capacity of most household storage tanks is insufficient to meet the year-round water demands (cited by 151 users; Smith’s Salience Index (SSI) = 0.671), and around 53% of the users relied on another water source besides the RWH system. The users frequently cleaned various components of the RWH system, although they did not pay much attention to cleaning the roof catchment. Most users did not have sufficient knowledge of water treatment methods (cited by 10 users; SSI = 0.033) or water quality testing protocol (cited by 29 users; SSI = 0.084). Proximity to the house (cited 222 times by the users, SSI = 0.589) is considered the primary benefit of the RWH system. The absence of adequate functional components (cited by 56 users; SSI = 0.170) and having to share water with other households (cited by 23 users; SSI = 0.068) were highlighted as the two main problems associated with the use of the RWH system. The users also highlighted the lack of training on operation and maintenance (O&amp;M) and the absence of monitoring support. This study provides clues to strengthening existing RWH system intervention programs in the water-challenged regions of Bangladesh.

Phytoplankton Community in Relation to Environmental Variables in the Tidal Mangrove Creeks of the Pasur River Estuary, Bangladesh

The Pasur River estuary (PRE) provides vital fishery resources and supports millions of livelihoods in the southwestern coastal region of Bangladesh. Our research focused on phytoplankton community assemblages, alpha diversity indices, and the seasonal succession of major phytoplankton species in relation to physicochemical parameters in the tidal mangrove creeks of the Pasur River estuary. Spatial and temporal variations were assessed by water sampling at 17 stations in the study area from January to December 2019. The mean salinity level in the tidal mangrove creeks of the PRE was significantly (p &lt; 0.05) higher during the dry season than during the wet season. Spatially, no significant variation (p &gt; 0.05) was observed in the dissolved inorganic nitrogen and dissolved inorganic phosphorus between PRE and mangrove creeks, but temporally, the variables varied significantly (p &lt; 0.05). Spatially, no significant variation (p &gt; 0.05) was observed in the alpha diversity of the phytoplankton community but significantly (p &lt; 0.05) varied temporally. Blue-green algae became dominant in the oligohaline conditions during the wet season, while diatoms were dominant during the dry season which severely depleted dissolved silica. In terms of phytoplankton species diversity, our study classifies the study areas as highly diversified zones. Phytoplankton succession from diatoms (dry season) to blue-green algae (wet season) is attributed to the changes in the physicochemical and nutrient parameters depending on seasonal environmental parameter fluctuations. This study illustrated that phytoplankton diversity and density varied with the degrees of habitat and seasonal changes, implying the potential impacts of anthropogenic activities and natural causes on their community structure in tropical estuaries and mangrove creeks.