RESUMO
Preserving the quality of groundwater has become Bangladesh's primary challenge in recent years. This study explores temporal trend variations in groundwater quality on a broader scale across 18 stations within the Dhaka division over 35 years. The data set encompasses an analysis of 15 distinct water quality parameters. Modified Mann-Kendal, Sens Slope and Mann-Kendal tests were performed to determine the trend's variation and slope. In addition, the spatial-temporal changes in the quality of groundwater are studied through Geographic Information System (GIS) mapping and Piper diagram was applied to identify the unique hydrochemical properties. This is the first study conducted on this area using various trends analysis and no in-depth study is available highlighting the trends analysis of groundwater quality on a larger magnitude. In contrast, the correlation matrix reveals a high association between Mg2+ and SO42-, Na+ and Cl- that affects salinity and overall hardness at the majority of sites. The Piper diagram also demonstrates that the groundwater in Madaripur Sadar has major salinity issues. The analysis reveals a distinctive dominance of bicarbonate (HCO3-) ions across all sampling stations, with (HCO3-) equivalent fractions consistently ranging from 0.70 to 0.99 which can cause a significant impact on groundwater uses. This extensive analysis of long-term groundwater quality trends in the Dhaka Division enables researchers to comprehend the overall transition of groundwater quality for hardness related complications in future. Moreover, it can be a baseline study considering the valuable implications and future steps for sustainable water resource management in this region.
RESUMO
Water scarcity has increased dramatically in many parts of the world and has become a major environmental problem globally in recent years. To address this challenge, researchers are continuously exploring and investigating different water sources and the relevant abstraction method. South Asian countries are not an exception in this regard. Specifically, how optimization has been done during the water abstraction process is becoming a key research agenda in South Asian region. This study attempts to systematically review the optimization of groundwater abstraction research in the South Asian region. First, bibliometric analysis has been performed to quantitatively assess the current research trends in the optimization of groundwater abstraction research. Second, a qualitative analysis has been done to get more insights into the different abstraction methods and simulation models used in groundwater abstraction research. This study has addressed the gap and explored research streams through scientific and conceptual mapping of the optimization of groundwater abstraction research. As revealed, the year 2020 is the most productive in groundwater abstraction research. Indian Institute of Technology and India were found to be the most impactful institution and countries in this field. The most studied area in groundwater abstraction research was found to be sustainable groundwater management, the geochemical process of controlling groundwater evolution, the Spatio-temporal variability of groundwater and the supply-demand of water during dry seasons. As revealed, statistical and mathematical modelling analysis is the most used approach in these studies. The findings of this study suggested that the water scarcity problem can be fixed by improving the design and operational techniques of the groundwater abstraction method and by using the different water sources collectively. This study further provides future directions and opportunities for research in the field of the groundwater abstraction process.
RESUMO
Drinking water contamination is one of the most pressing concerns for the people of Bangladesh as they rely on groundwater to meet their water needs. The existing water sources of Bangladesh are losing potability due to natural, anthropogenic, and geogenic factors, resulting in acute to severe health consequences. To address the issue of safe drinking water, researchers are constantly examining potential sources that cause the pollution of drinking water. Through bibliometric and systematic research, the current work seeks to review the past research on microbiological and chemical contamination of drinkable water in Bangladesh. The bibliometric review provides insights into the research trends, notable authors, countries, and institutions, whereas the systematic review unfolds the key research areas, the contamination process, and the strategies used to mitigate the contamination process. The results show that arsenic and various coliform bacteria are the most commonly reported sources of chemical and microbiological contaminants that degrade water quality. The study demonstrates that the most crucial factors influencing arsenic mobilization include microbial decomposition of organic matter (biologically available organic matter, for example, peat), arsenic adsorption by metal-oxyhydroxides, Fe-Mn oxyhydroxide, chemical fertilizers, pond excavation, and altering of groundwater hydrology. The studies also indicated the sources that contribute to the microbiological quality decline. The current work has addressed the scope of future research.