Evaluating the impact of groundwater on cotton growth and root zone water balance using Hydrus-1D coupled with a crop growth model

Abstract

a b s t r a c tGroundwater is an important factor that needs to be considered when evaluating the water balance of the soil-plant-atmosphere system and the sustainable development of arid oases. However, the impact of shallow groundwater on the root zone water balance and cotton growth is not fully understood. In this study, we have first analyzed the influence of the groundwater table depth on the seasonal maximum leaf area index of cotton, the average seasonal water stress, cotton yield, actual transpiration, actual evaporation, and capillary rise using experimental data collected at the Aksu water balance station, in Xinjiang, northwest of China and the Hydrus-1D variably-saturated soil water flow model coupled with a simplified crop growth model from SWAT. The coupled model has been first calibrated and validated using field observations of soil water content, leaf area index, cotton height, the above ground biomass, and cotton yield comparisons between measured and modeled variables have shown a reasonable agreement for all variables. Additionally, with a validated model, we have carried out numerical experiments from which we have concluded that groundwater is a major water resource for cotton growth in this region. The capillary rise from groundwater contributes almost 23% of crop transpiration when the average groundwater depth is 1.84 m, which is the most suitable groundwater depth for this experimental site. We have concluded that cotton growth and various components of the soil water balance are highly sensitive to the groundwater table level. Different positions of the groundwater table showed both positive and negative effects on cotton growth. Likewise, cotton growth has a significant impact on the capillary rise from groundwater. As a result, groundwater is a crucial factor that needs to be considered when evaluating agricultural land management in this arid region. The updated Hydrus-1D model developed in this study provides a powerful modeling tool for evaluating the effects of the groundwater table on local land management.

Evaluation of crop coefficients, water productivity, and water balance components for wine grapes irrigated at different deficit levels by a sub-surface drip

“…Similarly, Deb et al (2011) reported RMSE values similar to our study at various depths for water distribution simulation under a pecan tree. However, Han et al (2015) recorded higher RMSE during calibration than validation for cotton.…”

New features of version 3 of the HYDRUS (2D/3D) computer software package

“…Zhou et al (2012) coupled HYDRUS-1D with the WOFOST crop growth model (Boogaard et al, 1998), and used the resulting code to simulate the growth and yield of irrigated wheat and maize (Li et al, , 2014. Han et al (2015) similarly coupled HYDRUS-1D with a simplified crop growth version used in SWAT, based on the EPIC root growth model (Williams et al, 1989). They used the coupled model to simulate the contribution and impact of groundwater on cotton growth and root zone water balance.…”

Coupling DSSAT and HYDRUS-1D for simulations of soil water dynamics in the soil-plant-atmosphere system

“…Similarly, HYDRUS have been coupled successfully with existing crop and root growth models (e.g., Groenendyk et. al., 2012;Han et al, 2015;Hartmann et al, 2017;Li et al, 2014;Peña-Haro et al, 2012;Wang et al, 2014;Zhou et al, 2012). For example, Peña-Haro et al (2012) integrated WOFOST, a crop growth and production model, with HYDRUS-1D as well as with MODFLOW-2000 (Harbaugh et al, 2000), the latter being a saturated flow model.…”