Impact of water table on hierarchically nested groundwater flow system

Abstract

Water table configuration gives rise to hierarchically nested groundwater flow systems. However, there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flow systems. Moreover, it remains challenging to identify characteristics of water table space variation through limited groundwater observations at the regional scale. Based on two ideal two-dimensional cross-section analytical models, this study presents a simplified approach to preliminarily assess the nonlinear interactions between water table variation and three driving factors: Topography, geology and climate. Two criteria, C1 and C2, are utilized to address issues at different scales ranging from basin to local: (i) the influence of various factors on water table configuration; and (ii) the influence of water table on groundwater flow pattern. Then, the Ordos Plateau is taken as an example to explore the role of the water table in nested groundwater systems using the provided approach and criterion. The application of this approach in the Ordos Plateau demonstrates its appropriateness as a practical method for preliminarily determining the characteristics of water table configuration and its impact on flow systems. The study explores the mechanism influencing spatial variation in the water table and improves understanding of the interaction between topography, geology, and climate on groundwater flow patterns.

Keywords

• water table configuration
• groundwater flow pattern
• analytical models
• top boundary conditions
• ordos plateau