Application of a Linked Hydrodynamic–Groundwater Model for Accurate Groundwater Simulation in Floodplain Areas: A Case Study of Irtysh River, China

Abstract

The rich biodiversity in the floodplain area is influenced by both floodplain floods and groundwater (GW). To protect the ecological environment in the floodplain area, it is essential to study the interaction between floodplain floods and GW. The objective of this paper is to propose a coupling strategy between a hydrodynamic model and a GW model to provide an accurate simulation tool for quantifying the interaction between floodplain floods and GW. The case study is conducted in the floodplain area of the middle reaches of the Irtysh River in northwest China. Firstly, a two-dimensional hydrodynamic model based on TELEMAC-2D is constructed to accurately simulate floodplain floods under wetting and drying conditions. Secondly, a GW model based on MODFLOW is developed. Finally, a coupling strategy is proposed to achieve accurate and efficient integration between the hydrodynamic model and the GW model. The calibration and verification results of the model demonstrate high accuracy, with root mean squared error (RMSE) values of 0.51 m and 0.77 m between observed and calculated GW levels for the hydrodynamic–GW coupled model. The water balance results indicate that floodplain floods serve as the largest GW recharge source in the study area, while phreatic evaporation is the primary GW discharge item. This paper represents a novel attempt to couple a two-dimensional hydrodynamic model with a GW model. The research results provide a scientific tool for the ecological restoration of floodplain areas considering both surface water and GW, as well as the comprehensive management and regulation of wetland water resources and the water environment.

Numerical Modeling of Groundwater Dynamics and Management Strategies for the Sustainable Groundwater Development in Water-Scarce Agricultural Region of Punjab, Pakistan

“…A plot between simulated and observed heads is shown in Figure 10. The applications of MODFLOW for groundwater table simulations has also been reported with reasonable accuracy in previous studies [68][69][70].…”

Numerical Simulation and Validation of Constructed Wetlands for Effluent Treatment in eastern China : An Evaluation of MIKE21 in Enhancing Water Purification Efficiency

“…Furthermore, it also allows for the evaluation and refinement of CW functionalities (Guo et al, 2023). In this context, two-dimensional models have been extensively used in CW research to analyze the impact of geometric configurations on retention times, flow dynamics, and pollutant kinetics despite their drawbacks (Kumar et al, 2021;Liu et al, 2023). Numerous studies have recently incorporated threedimensional numerical models into CW simulations, thus, revealing differences in total phosphorus (TP) removal efficiencies between horizontal subsurface flow (HSSF) and wave subsurface flow (WSSF) CWs (Wang et al, 2011).…”

Genetic Diversity of Dominant Species Betula pendula in River Valley Forests in the Irtysh River Basin and Sustainable Conservation Measures for the Future

“…Owing to its unique geographical location and climatic conditions, the plant species found in this region belong to the European-Siberian Taiga boreal forest. During the period of May and June each year, due to the snowmelt in the mountains, the river runoff in the basin increases, resulting in river overflow and floodplain floods that last for nearly a month [8]. On the banks of its tributaries and in the lowlands there are large areas of forests called "river valley forests".…”