Dilip Datta | Khulna University, Bangladesh (original) (raw)

Papers by Dilip Datta

Khulna University studies, Nov 28, 2006

The study deals with the nature of solute load as well as the spatial distribution and the biogeo... more The study deals with the nature of solute load as well as the spatial distribution and the biogeochemical processing of the C, N and P in the suspended sediments from rivers in and around the Sundarbans collected during August-September 2002. The geochemistry of the solute load suggests that oceanic surface processes are important in and around the Sundarbans ecosystem and subduing the continental carbonate weathering processes prevailing over the Bengal basin. Despite a low concentration, significant spatial variation in Total Organic Carbon (TOC) and Total Nitrogen (TN) content in the suspended sediments exist in and around the Sundarbans, where as Plant Available Phosphorus (PAP) does not show any significant spatial variation. Excellent correlation between TOC and TN suggests regulation of TN by organic matter. However, the presence of considerable amount of inorganic nitrogen (ca. ~ 0.10 mg.g-1) may be estimated from such relationship, which is more important in the periphery (ca. ~ 0.19 mg.g-1) than in the interior Sundarbans (ca. ~ 0.03 mg.g-1) and may be of anthropogenic origin. The importance of inorganic nitrogen is also evident from the low TOC: TN ratio (varying from 2.96 to 6.42) in the ecosystem which could also be attributable to the almost complete degradation of the organic matter. Negative and poor/no correlation between PAP with TOC and TN suggest that phosphorus is not the only limiting factor in biomass production in the ecosystem.

Water, Flood Management and Water Security Under a Changing Climate, 2020

Ecological Processes, 2017

Introduction: Mangrove forests are highly productive ecosystems distributed along the tropical co... more Introduction: Mangrove forests are highly productive ecosystems distributed along the tropical coast line. Nutrient biogeochemistry of mangroves are primarly driven by both allochthonous and autochthonous sources. Characterization of organic matter in coastal ecosystems enables to understand the biogeochemical transformation of organic matter and its influence on ecosystem productivity in response to various changing environmental conditions. Therefore, the elemental and stable carbon and nitrogen levels were employed to understand the organic matter (OM) dynamics in the Sundarban mangrove ecosystem (India-Bangladesh). Results: Differences in stable isotope values indicate that variable sources influence the OM dynamics in Sundarban sediments. The progressive enrichment in δ 13C levels along the land-coastal continuum indicates that the terrestrial and marine inputs are dominant at the landward and seaward ends, respectively. The CuO oxidationderived lignin phenol monomers describe significant levels of total lignin are preserved in Sundarban mangrove sediments during diagenesis. The phenol monomer ratios are lower than the plant litter explaining that aromatic ring cleavage is the dominant mechanism for the lignin degradation. Furthermore, the Ad/Al ratios were higher than the plant litter explaining the oxidation of propyl side chain of vascular OM influencing the carbon cycling in Sundarban sediments. Largely, the Ad/Al ratios describe the vascular OM degradation is through the oxidation of propyl side chain. Conclusions: The regional variability in land-use regulates the spatial variability in C, N, OC/TN ratio, δ 13C and δ 15N between the Indian and the Bangladesh Sundarban mangroves and indicates that in the upstream terrestrial organic matter and/or mangrove plant litter contribute significant amount of organic matter, whereas the marine POC influences the organic matter dynamics in downstream. The three end-member mixing model applying terrestrial plant litter, seston, and marine POC as end-members explains the relative contribution of OM from various sources, and marine inputs were dominant in Sundarban sediments.

Journal of Environmental Management, 2021

The indirect, unplanned use of urban wastewater by peri-urban farmers in developing countries pos... more The indirect, unplanned use of urban wastewater by peri-urban farmers in developing countries poses a severe risk to the environment and the farmers. Planned water reuse could contribute substantially to the irrigation water demand in peri-urban agriculture and minimize the risk. However, implementing such practice requires a thorough evaluation of stakeholder's perception and the scope within the existing organizational structures. This paper aims to assess the level of awareness, perception, and willingness of different stakeholders toward current practices and the prospect of urban water reuse in Khulna City-one of the most vulnerable cities located in the southwest of Bangladesh due to the consequences of rapid climate changes in the Bengal delta. Also, institutional arrangements and their functioning were analyzed to understand the current sectoral performance. One questionnaire with 385 respondents from the urban area, 32 in-depth interviews and one focus group discussion with farmers in the peri-urban area, and ten interviews with key informants from the government and nongovernment organization was conducted. Results indicate an overall positive attitude among major stakeholder groups toward planned water reuse for peri-urban agriculture. More than half of the citizens (53%) are willing to pay for the treatment of wastewater and majority of the farmers (66%) are willing to pay for the supply of better-quality irrigation water. However, the public sector responsible for wastewater collection and treatment requires adjustment in rules and regulations to implement planned water reuse. Interrelated factors such as lack of transparency and coordination, shifting responsibilities to other organizations, lack of required resources need to be addressed in the updated rules and regulations. Strategies to enforce current regulations and align all stakeholders are also crucial for collection and treatment of wastewater and its subsequent use for crop production.

Climate Risk Management, 2021

Abstract Farmers in the Bengal Delta are confronted with increasing hydroclimatic risks due to cl... more Abstract Farmers in the Bengal Delta are confronted with increasing hydroclimatic risks due to climate variability and change. The co-production of climate information services that address the farmers' needs could potentially assist farmers with climate-sensitive decision-making and managing their risks. This study aims to investigate how the co-production of climate information services through forecast visualization and communication has improved forecast uptake for climate-sensitive decision-making of smallholder farmers. We applied a farmer field school approach to communicating visual diagrams for 7-day, 14-day, and seasonal forecasts during face-to-face meetings using printed paper, and smartphone applications. Results show that diagram-based forecast visualization and a combined communication approach integrating face-to-face interaction using printed paper and a smartphone app have improved uptake of information services by farmers. Capacity building and frequent interactions at farmer field schools contribute to a better understanding and trust of visual forecasts, interpretation skills, and decision-making capacity of smallholder farmers. We conclude that the co-production effort with farmers combined with the capacity building has resulted in wider sharing, dissemination, and uptake of scientific forecasts for climate-sensitive decision-making by smallholders in the Lower Bengal Delta.

Science of The Total Environment, 2019

Agriculture in delta areas of emerging economies is highly reliant on the provision of water with... more Agriculture in delta areas of emerging economies is highly reliant on the provision of water with adequate quality. This quality is often under pressure by season-related saltwater intrusion and poor domestic or industrial wastewater management. Methods to separate these two negative impacts on water quality for the delta areas are lacking but essential for proper management and supply of irrigation water. Therefore, the main aim of this research is to propose a method that maps salt and wastewater impacts on seasonal water quality and relate that to different land uses. Khulna, a delta city of Bangladesh was taken as a representative case study. Surface water samples have been collected from different city locations in winter, summer and monsoon seasons, and were analyzed for a variety of chemical-physical water quality parameters. Spatio-temporal variation maps were generated using Inverse Distance Weighted (IDW) interpolation method, and weighted overlay method was employed to map the current irrigation water use suitability based on FAO guidelines for the interpretations of water quality for irrigation. The influence of land-use on water quality was assessed by correlation analysis followed by bi-variate linear regression analysis. Analysis indicated significant (p < 0.05) seasonal dependent variation in water quality parameters, especially for saltwater influenced and generic water quality parameters. Also, the land-use percentage within 500 m radii to the sampling stations had a significant positive correlation with several parameters indicating saltwater and urban wastewater influences. Weighted overlay analysis revealed that during summer, approximately 1/3rd of the total studied area has a severe restriction for irrigation water use. The method presented here was shown to be effective in presenting variabilities on the effects of salinization and wastewater discharge on water quality in urbanized deltas and can be used as a knowledge base for formulating and implementing future urban infrastructure planning to improve irrigation water quality.

Management and Sustainable Development of Coastal Zone Environments, 2010

... of approximately 8750 hectares of mangrove loss due to salt-water intrusion, dike and ... whi... more ... of approximately 8750 hectares of mangrove loss due to salt-water intrusion, dike and ... while it is actively acting on different coastal processes (eg, salinity, sedimentation etc.). ... In: Proceedings of the national workshop on Coastal area resource development and management. ...

Water Policy, 2018

Many urbanised deltas face development challenges due to growing economies, populations and clima... more Many urbanised deltas face development challenges due to growing economies, populations and climate change. Changes in land–water strategies are often required, as ‘business-as-usual’ solutions are no longer sufficient. The aim of this paper was to study tidal river management (TRM) as a strategic innovation, and trace how it is appreciated by people and used in master plans to address congested rivers and waterlogging in Bangladesh. In this context, a strategic innovation can be categorised as having four features: (i) it is a fundamental reconceptualisation of business as usual strategies; (ii) it is rule breaking and reshapes markets; (iii) it offers value improvement for livelihoods; (iv) it is sustainable. The case study analysis was built from 17 interviews, a focus group discussion and numerous documents. The case analysis revealed that tidal river management is very different (local, natural, complex) from mainstream engineering strategies for tidal rivers and polder systems...

Journal of Hydrology, 1997

The Bengal drainage basin is geologically one of the youngest and tectonically most active denuda... more The Bengal drainage basin is geologically one of the youngest and tectonically most active denudation regimes of the world, and encompasses the total lower reaches of the Ganges-Brahmaputra-Meghna (GBM) drainage basin. The GBM river system contributes around 4.5% of the total annual global freshwater flux to the oceans. The solute load of the GBM river system is dominated by the carbonate weathering products of the transport-limited denudation regime. However, in the Meghna basin, which drains a mountainous region, silicate weathering is slightly more predominant, and the solute load tends to be more influenced by the atmospheric contribution. The river system represents about 5% (152 × 10 6 t yr −1) of the annual global chemical flux to the world's oceans. The chemical denudation rate of the GBM system in the Bengal basin, is one of the world's highest (79-114 t km −2 yr −1), suggesting intensive weathering and erosion in the drainage basin both in Bangladesh as well as in the hinterlands of India and China.

Environmental Geology, 1997

The Bengal basin, Bangladesh, represents one of the most densely populated recent floodplains of ... more The Bengal basin, Bangladesh, represents one of the most densely populated recent floodplains of the world. The sediment flux through the basin is one of the highest on a global scale. A significant portion of this sediment load find its sink in the basin itself because of its lower elevation and frequent flooding. The textural, mineralogical and chemical nature of the sediments thus have an important bearing on the environmental quality of the basin as well as for the Bay of Bengal. The sediment load of the Ganges-Brahmaputra-Meghna (GBM) river system consists exclusively of fine sand, silt and clay at their lower reaches within the Bengal basin, Bangladesh, and is deposited under uniformly fluctuating, unidirectional energy conditions. The sediments have a close simitarity in grain size with the sediments of the surrounding floodplain. The mineral assemblage is dominated by quartz and feldspars. Illite and kaolinite are the major clay minerals, and occur in almost equal proportion in bed sediments. The heavy mineral assemblage is dominated by unstable minerals which are mostly derived from high-rank metamorphic rocks. The characteristic smaller grainsize, i.e. having large surface-to-mass ratios, and the mineralogy of sediments suggests that they are susceptible to large chemical adsorptive reactions and thus could serve as a potential trap for contaminants. However, the sediments of the GBM river system in the Bengal basin, Bangladesh, shows lower concentration of Pb, Hg and As, and a marginally higher value for Cd as compared to that of standard shale. Considering population density and extensive agricultural practice in the basin, the sediments can in the long run become contaminated.

Organic geochemistry, 1999

The Bengal basin is one of the geologically youngest and tectonically active drainage regimes of ... more The Bengal basin is one of the geologically youngest and tectonically active drainage regimes of the world which includes the total Lower Ganges–Brahmaputra–Meghna (GBM) river system, one of the highest sediment dispersal systems in the world. The sediment load in ...

Sustainability

Farmers in the lower Bengal Delta around the city of Khulna, Bangladesh, are particularly vulnera... more Farmers in the lower Bengal Delta around the city of Khulna, Bangladesh, are particularly vulnerable to hydro-climatic variability. Phenomena such as heavy rain, drought and salt intrusion increasingly affect their crop production, with far-reaching socio-economic and environmental impacts. Reliable hydro-climatic information service received in a timely manner could help farmers improve their responses to hydro-climatic variability, thus improving their agricultural decision-making. However, significant challenges persist regarding information uptake and the role of information from the available sources. We designed an explorative research framework combining different participatory methods and analysis of climate data. Our aim was to examine three key research questions: (i) what information is currently available to farmers for agricultural practices and decision-making? (ii) what is the perceived quality of the available hydro-climatic information in response to water and weath...

The project was started in the year 2011 and after completion of the first year of the project in... more The project was started in the year 2011 and after completion of the first year of the project in the year 2012 the second phase started in the year 2014-15. The collaborating institutes/universities in the project were

Environmental Science & Policy

Due to both natural and anthropogenic forces, the south west part of the Ganges-Brahmaputra coast... more Due to both natural and anthropogenic forces, the south west part of the Ganges-Brahmaputra coastal area is facing diverse problems such as waterlogging, salinity, and loss of biodiversity. In order to address these challenges, local people have identified 'tidal river management (TRM)' as a comprehensive approach for sustainably managing this part of the Ganges-Brahmaputra Basin. However, due to institutional limitations, mismanagement and social conflicts, application of the TRM approach is not straightforward. In order to identify existing implementation barriers and to effectively apply the TRM approach, a transdisciplinary approach is examined for its potential to inform the reshaping of TRM governing values and actions. It is argued that a thorough application of a transdisciplinary framework is essential, supported by the active involvement of key agencies and local stakeholders. The proposed transdisciplinary framework can potentially be applied to TRM projects for solving waterlogging and associated problems in order to achieve greater sustainability of the area.

Shrimp culture along the coast of southwest Bangladesh was a traditional practice and usually res... more Shrimp culture along the coast of southwest Bangladesh was a traditional practice and usually restricted within land between the levees and the river channels (Deb, 1998; Islam et al., 2005; Nandy et al., 2007). However, since early seventies of the last century farmers and investors are encouraged to involve most in shrimp farming within polders—large areas within coastal embankments meant for protecting crop lands from tidal waves, surges and saline intrusion—in response to the demand from international high value customers for shrimp (a luxury food item), low investment and unexpectedly high return where government policies played a favourable role (Alauddin and Tisdel, 1998) and thus ushered the beginning of present shrimp era (BCAS, 2001). Outbreak of disease was a major hindrance for shrimp culture (Alam et al., 2007) and during 1996 Khulna region experienced such impact on approximately 90% of its extensive shrimp farms with a loss of 20% in total shrimp production (Chowdhury...

jollygreengiant.fullnetwork.org, 2006

The Khulna City Corporation (KCC) in southwestern Bangladesh lies on the Late Holocene-Recent all... more The Khulna City Corporation (KCC) in southwestern Bangladesh lies on the Late Holocene-Recent alluvium of the Ganges deltaic plain in the north and Ganges estuarine plain in the south. Lithologically the area is composed of coarse to very fine sand, silt, silty clay and clay in various porportion upto a depth of 300m. Stratigraphically shows seven cycles of sedimentation having age connotation from Upper Miocene to Recent age. The SPT (Standard Penetration Test) value of the investigated area range between 1 and 9 from surface to 5m deep and 1 to 27 from 5m to 15m below which was used to prepare a SPT zonation map that clearly delineates the KCC area into 4 zones. Here, the liquid limit, plasticity index and the natural moisture content (NMC) range from 38 to 59%, 9 to 30% and 16.5% to 42% respectively. The shear strength of the upper subsoil horizons in the investigated area is low. Low shearing strength in the upper soil horizon with compressive index from 0.123 to 0.335 is indicative of soil vulnerability to excessive settlement under high load. The cohesive nature of soil in the KCC area with high colloidal content, high liquid and plastic limit indicate medium to high sensitivity of the soil to moisture that could not support heavily loaded buildings and structures. The problems can be avoided by considering special type of foundation, increasing the width of basements of structures and granular backfilling. Based on geomorphology, stratigraphic litho-succession, soil types, percentage of sand, silt and clay in the soil, liquid limit, plasticity index, NMC, liquefaction, settlement and SPT zonation, the study area have been classified into four geotechnical units, where unit-I is best and unit-IV is rank lowest for urbanization. Considering the factors of geotechnical parameters and environmental degradation by natural and anthropogenic hazards a future land suitability map has been prepared for future urban planning of the Khulna City area.

Atmosphere

Hydroclimatic information services are vital for sustainable agricultural practices in deltas. Th... more Hydroclimatic information services are vital for sustainable agricultural practices in deltas. They advance adaptation practices of farmers that lead to better economic benefit through increased yields, reduced production costs, and minimized crop damage. This research explores the hydroclimatic information needs of farmers by addressing (1) what kind of information is needed by the periurban delta farmers, and (2) whether information needs have any temporal dimension that changes with time following capacity building during coproduction of information services. Results reveal that the attributes of weather and water-related forecasts most affecting the farmers are rainfall, temperature, water, and soil salinity, along with extreme events such as cyclone and storm surges. The majority of the male farmers prefer one- to two-week lead-time forecasts for strategic and tactical decision-making; while female farmers prefer short-time forecasts with one-day to a week lead time that sugges...

Sustainability

Farmers in the lower Bengal Delta around the city of Khulna, Bangladesh, are particularly vulnera... more Farmers in the lower Bengal Delta around the city of Khulna, Bangladesh, are particularly vulnerable to hydro-climatic variability. Phenomena such as heavy rain, drought and salt intrusion increasingly affect their crop production, with far-reaching socio-economic and environmental impacts. Reliable hydro-climatic information service received in a timely manner could help farmers improve their responses to hydro-climatic variability, thus improving their agricultural decision-making. However, significant challenges persist regarding information uptake and the role of information from the available sources. We designed an explorative research framework combining different participatory methods and analysis of climate data. Our aim was to examine three key research questions: (i) what information is currently available to farmers for agricultural practices and decision-making? (ii) what is the perceived quality of the available hydro-climatic information in response to water and weath...

Khulna University studies, Nov 28, 2006

The study deals with the nature of solute load as well as the spatial distribution and the biogeo... more The study deals with the nature of solute load as well as the spatial distribution and the biogeochemical processing of the C, N and P in the suspended sediments from rivers in and around the Sundarbans collected during August-September 2002. The geochemistry of the solute load suggests that oceanic surface processes are important in and around the Sundarbans ecosystem and subduing the continental carbonate weathering processes prevailing over the Bengal basin. Despite a low concentration, significant spatial variation in Total Organic Carbon (TOC) and Total Nitrogen (TN) content in the suspended sediments exist in and around the Sundarbans, where as Plant Available Phosphorus (PAP) does not show any significant spatial variation. Excellent correlation between TOC and TN suggests regulation of TN by organic matter. However, the presence of considerable amount of inorganic nitrogen (ca. ~ 0.10 mg.g-1) may be estimated from such relationship, which is more important in the periphery (ca. ~ 0.19 mg.g-1) than in the interior Sundarbans (ca. ~ 0.03 mg.g-1) and may be of anthropogenic origin. The importance of inorganic nitrogen is also evident from the low TOC: TN ratio (varying from 2.96 to 6.42) in the ecosystem which could also be attributable to the almost complete degradation of the organic matter. Negative and poor/no correlation between PAP with TOC and TN suggest that phosphorus is not the only limiting factor in biomass production in the ecosystem.

Water, Flood Management and Water Security Under a Changing Climate, 2020

Ecological Processes, 2017

Introduction: Mangrove forests are highly productive ecosystems distributed along the tropical co... more Introduction: Mangrove forests are highly productive ecosystems distributed along the tropical coast line. Nutrient biogeochemistry of mangroves are primarly driven by both allochthonous and autochthonous sources. Characterization of organic matter in coastal ecosystems enables to understand the biogeochemical transformation of organic matter and its influence on ecosystem productivity in response to various changing environmental conditions. Therefore, the elemental and stable carbon and nitrogen levels were employed to understand the organic matter (OM) dynamics in the Sundarban mangrove ecosystem (India-Bangladesh). Results: Differences in stable isotope values indicate that variable sources influence the OM dynamics in Sundarban sediments. The progressive enrichment in δ 13C levels along the land-coastal continuum indicates that the terrestrial and marine inputs are dominant at the landward and seaward ends, respectively. The CuO oxidationderived lignin phenol monomers describe significant levels of total lignin are preserved in Sundarban mangrove sediments during diagenesis. The phenol monomer ratios are lower than the plant litter explaining that aromatic ring cleavage is the dominant mechanism for the lignin degradation. Furthermore, the Ad/Al ratios were higher than the plant litter explaining the oxidation of propyl side chain of vascular OM influencing the carbon cycling in Sundarban sediments. Largely, the Ad/Al ratios describe the vascular OM degradation is through the oxidation of propyl side chain. Conclusions: The regional variability in land-use regulates the spatial variability in C, N, OC/TN ratio, δ 13C and δ 15N between the Indian and the Bangladesh Sundarban mangroves and indicates that in the upstream terrestrial organic matter and/or mangrove plant litter contribute significant amount of organic matter, whereas the marine POC influences the organic matter dynamics in downstream. The three end-member mixing model applying terrestrial plant litter, seston, and marine POC as end-members explains the relative contribution of OM from various sources, and marine inputs were dominant in Sundarban sediments.

Journal of Environmental Management, 2021

The indirect, unplanned use of urban wastewater by peri-urban farmers in developing countries pos... more The indirect, unplanned use of urban wastewater by peri-urban farmers in developing countries poses a severe risk to the environment and the farmers. Planned water reuse could contribute substantially to the irrigation water demand in peri-urban agriculture and minimize the risk. However, implementing such practice requires a thorough evaluation of stakeholder's perception and the scope within the existing organizational structures. This paper aims to assess the level of awareness, perception, and willingness of different stakeholders toward current practices and the prospect of urban water reuse in Khulna City-one of the most vulnerable cities located in the southwest of Bangladesh due to the consequences of rapid climate changes in the Bengal delta. Also, institutional arrangements and their functioning were analyzed to understand the current sectoral performance. One questionnaire with 385 respondents from the urban area, 32 in-depth interviews and one focus group discussion with farmers in the peri-urban area, and ten interviews with key informants from the government and nongovernment organization was conducted. Results indicate an overall positive attitude among major stakeholder groups toward planned water reuse for peri-urban agriculture. More than half of the citizens (53%) are willing to pay for the treatment of wastewater and majority of the farmers (66%) are willing to pay for the supply of better-quality irrigation water. However, the public sector responsible for wastewater collection and treatment requires adjustment in rules and regulations to implement planned water reuse. Interrelated factors such as lack of transparency and coordination, shifting responsibilities to other organizations, lack of required resources need to be addressed in the updated rules and regulations. Strategies to enforce current regulations and align all stakeholders are also crucial for collection and treatment of wastewater and its subsequent use for crop production.

Climate Risk Management, 2021

Abstract Farmers in the Bengal Delta are confronted with increasing hydroclimatic risks due to cl... more Abstract Farmers in the Bengal Delta are confronted with increasing hydroclimatic risks due to climate variability and change. The co-production of climate information services that address the farmers' needs could potentially assist farmers with climate-sensitive decision-making and managing their risks. This study aims to investigate how the co-production of climate information services through forecast visualization and communication has improved forecast uptake for climate-sensitive decision-making of smallholder farmers. We applied a farmer field school approach to communicating visual diagrams for 7-day, 14-day, and seasonal forecasts during face-to-face meetings using printed paper, and smartphone applications. Results show that diagram-based forecast visualization and a combined communication approach integrating face-to-face interaction using printed paper and a smartphone app have improved uptake of information services by farmers. Capacity building and frequent interactions at farmer field schools contribute to a better understanding and trust of visual forecasts, interpretation skills, and decision-making capacity of smallholder farmers. We conclude that the co-production effort with farmers combined with the capacity building has resulted in wider sharing, dissemination, and uptake of scientific forecasts for climate-sensitive decision-making by smallholders in the Lower Bengal Delta.

Science of The Total Environment, 2019

Agriculture in delta areas of emerging economies is highly reliant on the provision of water with... more Agriculture in delta areas of emerging economies is highly reliant on the provision of water with adequate quality. This quality is often under pressure by season-related saltwater intrusion and poor domestic or industrial wastewater management. Methods to separate these two negative impacts on water quality for the delta areas are lacking but essential for proper management and supply of irrigation water. Therefore, the main aim of this research is to propose a method that maps salt and wastewater impacts on seasonal water quality and relate that to different land uses. Khulna, a delta city of Bangladesh was taken as a representative case study. Surface water samples have been collected from different city locations in winter, summer and monsoon seasons, and were analyzed for a variety of chemical-physical water quality parameters. Spatio-temporal variation maps were generated using Inverse Distance Weighted (IDW) interpolation method, and weighted overlay method was employed to map the current irrigation water use suitability based on FAO guidelines for the interpretations of water quality for irrigation. The influence of land-use on water quality was assessed by correlation analysis followed by bi-variate linear regression analysis. Analysis indicated significant (p < 0.05) seasonal dependent variation in water quality parameters, especially for saltwater influenced and generic water quality parameters. Also, the land-use percentage within 500 m radii to the sampling stations had a significant positive correlation with several parameters indicating saltwater and urban wastewater influences. Weighted overlay analysis revealed that during summer, approximately 1/3rd of the total studied area has a severe restriction for irrigation water use. The method presented here was shown to be effective in presenting variabilities on the effects of salinization and wastewater discharge on water quality in urbanized deltas and can be used as a knowledge base for formulating and implementing future urban infrastructure planning to improve irrigation water quality.

Management and Sustainable Development of Coastal Zone Environments, 2010

... of approximately 8750 hectares of mangrove loss due to salt-water intrusion, dike and ... whi... more ... of approximately 8750 hectares of mangrove loss due to salt-water intrusion, dike and ... while it is actively acting on different coastal processes (eg, salinity, sedimentation etc.). ... In: Proceedings of the national workshop on Coastal area resource development and management. ...

Water Policy, 2018

Many urbanised deltas face development challenges due to growing economies, populations and clima... more Many urbanised deltas face development challenges due to growing economies, populations and climate change. Changes in land–water strategies are often required, as ‘business-as-usual’ solutions are no longer sufficient. The aim of this paper was to study tidal river management (TRM) as a strategic innovation, and trace how it is appreciated by people and used in master plans to address congested rivers and waterlogging in Bangladesh. In this context, a strategic innovation can be categorised as having four features: (i) it is a fundamental reconceptualisation of business as usual strategies; (ii) it is rule breaking and reshapes markets; (iii) it offers value improvement for livelihoods; (iv) it is sustainable. The case study analysis was built from 17 interviews, a focus group discussion and numerous documents. The case analysis revealed that tidal river management is very different (local, natural, complex) from mainstream engineering strategies for tidal rivers and polder systems...

Journal of Hydrology, 1997

The Bengal drainage basin is geologically one of the youngest and tectonically most active denuda... more The Bengal drainage basin is geologically one of the youngest and tectonically most active denudation regimes of the world, and encompasses the total lower reaches of the Ganges-Brahmaputra-Meghna (GBM) drainage basin. The GBM river system contributes around 4.5% of the total annual global freshwater flux to the oceans. The solute load of the GBM river system is dominated by the carbonate weathering products of the transport-limited denudation regime. However, in the Meghna basin, which drains a mountainous region, silicate weathering is slightly more predominant, and the solute load tends to be more influenced by the atmospheric contribution. The river system represents about 5% (152 × 10 6 t yr −1) of the annual global chemical flux to the world's oceans. The chemical denudation rate of the GBM system in the Bengal basin, is one of the world's highest (79-114 t km −2 yr −1), suggesting intensive weathering and erosion in the drainage basin both in Bangladesh as well as in the hinterlands of India and China.

Environmental Geology, 1997

The Bengal basin, Bangladesh, represents one of the most densely populated recent floodplains of ... more The Bengal basin, Bangladesh, represents one of the most densely populated recent floodplains of the world. The sediment flux through the basin is one of the highest on a global scale. A significant portion of this sediment load find its sink in the basin itself because of its lower elevation and frequent flooding. The textural, mineralogical and chemical nature of the sediments thus have an important bearing on the environmental quality of the basin as well as for the Bay of Bengal. The sediment load of the Ganges-Brahmaputra-Meghna (GBM) river system consists exclusively of fine sand, silt and clay at their lower reaches within the Bengal basin, Bangladesh, and is deposited under uniformly fluctuating, unidirectional energy conditions. The sediments have a close simitarity in grain size with the sediments of the surrounding floodplain. The mineral assemblage is dominated by quartz and feldspars. Illite and kaolinite are the major clay minerals, and occur in almost equal proportion in bed sediments. The heavy mineral assemblage is dominated by unstable minerals which are mostly derived from high-rank metamorphic rocks. The characteristic smaller grainsize, i.e. having large surface-to-mass ratios, and the mineralogy of sediments suggests that they are susceptible to large chemical adsorptive reactions and thus could serve as a potential trap for contaminants. However, the sediments of the GBM river system in the Bengal basin, Bangladesh, shows lower concentration of Pb, Hg and As, and a marginally higher value for Cd as compared to that of standard shale. Considering population density and extensive agricultural practice in the basin, the sediments can in the long run become contaminated.

Organic geochemistry, 1999

The Bengal basin is one of the geologically youngest and tectonically active drainage regimes of ... more The Bengal basin is one of the geologically youngest and tectonically active drainage regimes of the world which includes the total Lower Ganges–Brahmaputra–Meghna (GBM) river system, one of the highest sediment dispersal systems in the world. The sediment load in ...

Sustainability

Farmers in the lower Bengal Delta around the city of Khulna, Bangladesh, are particularly vulnera... more Farmers in the lower Bengal Delta around the city of Khulna, Bangladesh, are particularly vulnerable to hydro-climatic variability. Phenomena such as heavy rain, drought and salt intrusion increasingly affect their crop production, with far-reaching socio-economic and environmental impacts. Reliable hydro-climatic information service received in a timely manner could help farmers improve their responses to hydro-climatic variability, thus improving their agricultural decision-making. However, significant challenges persist regarding information uptake and the role of information from the available sources. We designed an explorative research framework combining different participatory methods and analysis of climate data. Our aim was to examine three key research questions: (i) what information is currently available to farmers for agricultural practices and decision-making? (ii) what is the perceived quality of the available hydro-climatic information in response to water and weath...

The project was started in the year 2011 and after completion of the first year of the project in... more The project was started in the year 2011 and after completion of the first year of the project in the year 2012 the second phase started in the year 2014-15. The collaborating institutes/universities in the project were

Environmental Science & Policy

Due to both natural and anthropogenic forces, the south west part of the Ganges-Brahmaputra coast... more Due to both natural and anthropogenic forces, the south west part of the Ganges-Brahmaputra coastal area is facing diverse problems such as waterlogging, salinity, and loss of biodiversity. In order to address these challenges, local people have identified 'tidal river management (TRM)' as a comprehensive approach for sustainably managing this part of the Ganges-Brahmaputra Basin. However, due to institutional limitations, mismanagement and social conflicts, application of the TRM approach is not straightforward. In order to identify existing implementation barriers and to effectively apply the TRM approach, a transdisciplinary approach is examined for its potential to inform the reshaping of TRM governing values and actions. It is argued that a thorough application of a transdisciplinary framework is essential, supported by the active involvement of key agencies and local stakeholders. The proposed transdisciplinary framework can potentially be applied to TRM projects for solving waterlogging and associated problems in order to achieve greater sustainability of the area.

Shrimp culture along the coast of southwest Bangladesh was a traditional practice and usually res... more Shrimp culture along the coast of southwest Bangladesh was a traditional practice and usually restricted within land between the levees and the river channels (Deb, 1998; Islam et al., 2005; Nandy et al., 2007). However, since early seventies of the last century farmers and investors are encouraged to involve most in shrimp farming within polders—large areas within coastal embankments meant for protecting crop lands from tidal waves, surges and saline intrusion—in response to the demand from international high value customers for shrimp (a luxury food item), low investment and unexpectedly high return where government policies played a favourable role (Alauddin and Tisdel, 1998) and thus ushered the beginning of present shrimp era (BCAS, 2001). Outbreak of disease was a major hindrance for shrimp culture (Alam et al., 2007) and during 1996 Khulna region experienced such impact on approximately 90% of its extensive shrimp farms with a loss of 20% in total shrimp production (Chowdhury...

jollygreengiant.fullnetwork.org, 2006

The Khulna City Corporation (KCC) in southwestern Bangladesh lies on the Late Holocene-Recent all... more The Khulna City Corporation (KCC) in southwestern Bangladesh lies on the Late Holocene-Recent alluvium of the Ganges deltaic plain in the north and Ganges estuarine plain in the south. Lithologically the area is composed of coarse to very fine sand, silt, silty clay and clay in various porportion upto a depth of 300m. Stratigraphically shows seven cycles of sedimentation having age connotation from Upper Miocene to Recent age. The SPT (Standard Penetration Test) value of the investigated area range between 1 and 9 from surface to 5m deep and 1 to 27 from 5m to 15m below which was used to prepare a SPT zonation map that clearly delineates the KCC area into 4 zones. Here, the liquid limit, plasticity index and the natural moisture content (NMC) range from 38 to 59%, 9 to 30% and 16.5% to 42% respectively. The shear strength of the upper subsoil horizons in the investigated area is low. Low shearing strength in the upper soil horizon with compressive index from 0.123 to 0.335 is indicative of soil vulnerability to excessive settlement under high load. The cohesive nature of soil in the KCC area with high colloidal content, high liquid and plastic limit indicate medium to high sensitivity of the soil to moisture that could not support heavily loaded buildings and structures. The problems can be avoided by considering special type of foundation, increasing the width of basements of structures and granular backfilling. Based on geomorphology, stratigraphic litho-succession, soil types, percentage of sand, silt and clay in the soil, liquid limit, plasticity index, NMC, liquefaction, settlement and SPT zonation, the study area have been classified into four geotechnical units, where unit-I is best and unit-IV is rank lowest for urbanization. Considering the factors of geotechnical parameters and environmental degradation by natural and anthropogenic hazards a future land suitability map has been prepared for future urban planning of the Khulna City area.

Atmosphere

Hydroclimatic information services are vital for sustainable agricultural practices in deltas. Th... more Hydroclimatic information services are vital for sustainable agricultural practices in deltas. They advance adaptation practices of farmers that lead to better economic benefit through increased yields, reduced production costs, and minimized crop damage. This research explores the hydroclimatic information needs of farmers by addressing (1) what kind of information is needed by the periurban delta farmers, and (2) whether information needs have any temporal dimension that changes with time following capacity building during coproduction of information services. Results reveal that the attributes of weather and water-related forecasts most affecting the farmers are rainfall, temperature, water, and soil salinity, along with extreme events such as cyclone and storm surges. The majority of the male farmers prefer one- to two-week lead-time forecasts for strategic and tactical decision-making; while female farmers prefer short-time forecasts with one-day to a week lead time that sugges...

Sustainability

Farmers in the lower Bengal Delta around the city of Khulna, Bangladesh, are particularly vulnera... more Farmers in the lower Bengal Delta around the city of Khulna, Bangladesh, are particularly vulnerable to hydro-climatic variability. Phenomena such as heavy rain, drought and salt intrusion increasingly affect their crop production, with far-reaching socio-economic and environmental impacts. Reliable hydro-climatic information service received in a timely manner could help farmers improve their responses to hydro-climatic variability, thus improving their agricultural decision-making. However, significant challenges persist regarding information uptake and the role of information from the available sources. We designed an explorative research framework combining different participatory methods and analysis of climate data. Our aim was to examine three key research questions: (i) what information is currently available to farmers for agricultural practices and decision-making? (ii) what is the perceived quality of the available hydro-climatic information in response to water and weath...