Monitoring groundwater heads and estimating recharge in multi-aquifer systems illustrated by an irrigated area in north-west Bangladesh
Monitoring groundwater heads and estimating recharge in multi-aquifer systems illustrated by an irrigated area in north-west Bangladesh
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以孟加拉国西北部灌溉区为例，监测地下水水头并估算多含水层系统的补给量
DOI：
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发表时间：
2020
影响因子：
2.1
通讯作者：
M. Hasan
中科院分区：
文献类型：
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作者：
K. Rushton;M. Asaduz Zaman;M. Hasan
通过监测地下水位随深度和时间的变化，可以确定多含水层系统中地下水开采的影响。同样重要的是估计地下水系统的补给，包括灌溉的贡献。孟加拉国拉杰沙希巴林德的一项案例研究说明了这些方法。从深管井中抽取地下水使农业生产大幅度增加，但也使含水层中的地下水位显著福尔斯下降。监测不同深度的地下水位，并将其与岩性联系起来，表明在中间含水层中形成了额外的地下水位;这导致将含水层系统概念化为两个单元，上单元和下单元。估计潜在的补给含水层系统获得每日土壤水分平衡，这是增强，包括代表性的补给，从积水淹没稻田。在两年多的时间里，进行了详细的实地调查，包括每天记录地下水位、降雨量、温度和抽水灌溉时间;还收集了指挥区种植作物的信息。个人，但相互关联的，概念和计算模型的两个单位的发展。计算模型的输出与实测地下水位波动吻合良好。利用计算模型的信息，目前的抽象模式的可持续性被认为是。
The impact of groundwater abstraction in multi-aquifer systems can be identified by monitoring variations of groundwater heads with depth and with time. Equally important are estimates of recharge to the groundwater system including contributions from irrigation. A case study from the Rajshahi Barind in Bangladesh illustrates the methodologies. Abstraction of groundwater from deep tubewells has resulted in substantial increases in agricultural production but also significant falls in groundwater heads in the aquifers. Monitoring of the groundwater heads at different depths and relating these to the lithology has indicated the formation of an additional water table in an intermediate aquifer; this leads to the conceptualisation of the aquifer system as two Units, Upper and Lower. Estimates of the potential recharge to the aquifer system are obtained from a daily soil water balance which is enhanced to include the representation of recharge from standing water in flooded ricefields. Detailed fieldwork, over a period of more than 2 years, includes daily records of groundwater heads, rainfall, temperature and hours of pumping for irrigation; information about the crops grown in the command area is also collected. Individual, but interconnected, conceptual and computational models for the two Units are developed. The outputs of the computational models show good agreement with measured groundwater head fluctuations. Using information from the computational models, the sustainability of the current abstraction patterns is considered.