Use of HYDRUS-1D–GIS tool for evaluating effects of climate changes on soil salinization and irrigation management

ABSTRACT

In this study, HYDRUS-1D model was coupled with geographic information system (GIS) for evaluating the effects of climate changes on soil salinization. The coupled HYDRUS-1D–GIS system was applied in a coastal region (Gabes Oasis) for evaluating the effects of various climate change scenarios on temporal change in soil electrical conductivity (EC) and for developing irrigation practice that desalinates soils. The climate change scenarios were selected based on the climate change projections by 2050 and increased irrigation water allocations. There were three main findings. First, HYDRUS-1D and GIS were successfully coupled and used to perform simulation with consideration of the large differences in soil texture in the studied oasis. Second, for all climate change scenarios, spatial extent of EC for 2050 is projected to reach levels (> 4 dS m⁻¹) corresponding with being classified as saline soils. Third, with climate changing as simulated, it is recommended to increase irrigation water application with 20% or more than today to avoid further increases in soil EC. Overall, this study can be used as a guide to implement the most appropriate strategy of soil and water management.

KEYWORDS:

• Coastal region
• climate change
• oasis
• soil salinization
• soil management

Acknowledgments

The present work was supported by several research institutions (IRD, ANSDO, ROADG). The authors thank Prof. Jan W. Hopmans (Soil Hydrology & Irrigation Water Management Department, University of California Davis, USA) for relevant discussions. Also, the authors would like to thank the two anonymous reviewers for their helpful suggestions and comments.

Disclosure statement

No potential conflict of interest was reported by the authors.