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Description
Groundwater is a critical resource for agricultural irrigation and domestic water supply in the densely populated Halda watershed of southeastern Bangladesh. Increasing demand and potential climate variability necessitate a comprehensive assessment of this vital resource. This study aims to assess the temporal dynamics of groundwater storage and spatially delineate recharge potential zones within the Halda watershed. An integrated approach was employed, combining satellite remote sensing, in-situ data, and Geographic Information System (GIS) based modelling. Temporal variations in Groundwater Storage (GWS) from 2004 to 2014 were quantified using data from the Gravity Recovery and Climate Experiment (GRACE) mission, which tracks changes in terrestrial water storage, and were refined with soil moisture data from the Global Land Data Assimilation System (GLDAS). These satellite-derived results were validated against historical well data from the Bangladesh Water Development Board (BWDB) and contemporary field surveys. Furthermore, a Groundwater Recharge Potential Zone (GWRPI) map was developed using a GIS-based Multi-Criteria Decision Analysis (MCDA) that integrated six thematic layers: geology, soil, slope, rainfall, drainage density, and land use/land cover. The results revealed a strong inverse correlation between satellite-derived GWS anomalies and in-situ well depths, with a consistent two-month lag time between precipitation and aquifer response, a phenomenon common in the region's monsoonal hydrological systems.
Linear regression analysis of the GWS time-series indicated a declining trend across the study area, with depletion rates ranging from -0.11 to -0.14 cm/year during the study period. The recharge potential map revealed that zones with 'Good' to 'Very Good' potential are primarily confined to the alluvial deposits of the central river valley (the syncline), while the surrounding hilly structures (anticlines), composed of older sedimentary rocks, exhibit 'Poor' to 'Moderate' potential. In conclusion, the Halda watershed's groundwater resources experienced a net decline during the study period, and their natural recharge capacity is spatially limited to the floodplain areas. The findings highlight the vulnerability of the aquifer to sustained pressure and provide a scientifically grounded tool (the GWRPI map) for policymakers to target conservation efforts and implement managed aquifer recharge strategies, thereby promoting sustainable water resource management in this vital region.
| References | 1. Rashid, M. H., Abdullah-Al-Mamun, M., & Hassan, M. Q. (2020). Groundwater potential mapping in a hilly area of Bangladesh using a GIS-based analytical hierarchy process. Groundwater for Sustainable Development, 11, 100412. https://doi.org/10.1016/j.gsd.2020.100412, 2. Rodell, M., & Famiglietti, J. S. (2002). The potential of remote sensing for monitoring groundwater storage. In Remote Sensing and Water Resources (Vol. 5, pp. 119-126). AGU. 3. Syed, T. H., Famiglietti, J. S., Rodell, M., Chen, J., & Wilson, C. R. (2008). Analysis of terrestrial water storage variations in Asia. Journal of Hydrometeorology, 9(4), 755–769. https://doi.org/10.1175/2007JHM938.1 3. Yeh, H. F., Cheng, Y. S., Lin, H. I., & Lee, C. H. (2016). Mapping groundwater recharge potential zone using a GIS-based analytical hierarchy process. Sustainable Water Resources Management, 2(2), 181–195. https://doi.org/10.1007/s40899-016-0049-7 |
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| Country | Bangladesh |
| Green Housing & Porous Media Focused Abstracts | This abstract is related to Green Housing |
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