Comparing Sprinkler and Surface Irrigation for Wheat Using Multi-Criteria Analysis: Water Saving vs. Economic Returns

Hanaa Darouich,José Gonçalves,Maria Cameira,Paula Paredes,Luis Pereira

doi:10.3390/w9010050

Abstract

Coping with water scarcity using supplemental irrigation of wheat (Triticum aestivum L.) in the semi-arid northeast Syria is a great challenge for sustainable water use in agriculture. Graded borders and set sprinkler systems were compared using multi-criteria analysis. Alternative solutions for surface irrigation and for sprinkler systems were developed with the SADREG and the PROASPER design models, respectively. For each alternative, two deficit irrigation strategies were considered, which were characterized using indicators relative to irrigation water use, yields and water productivity, including farm economic returns. Alternatives were ranked considering two contrasting priorities: economic returns and water saving. A first step in ranking led to a selection of graded borders with and without precise land levelling and of solid set and semi-permanent sprinkler systems. Precise-levelled borders were better for water saving, while non-precise ones ranked higher for economic returns. Semi-permanent set systems have been shown to be better in economic terms and similar to solid set systems when water saving is prioritized. Semi-permanent sprinkler systems rank first when comparing all type of systems together regardless of the considered deficit irrigation strategy. Likely, border irrigation is appropriate when wheat is in rotation with cotton if the latter is surface irrigated. When peace becomes effective, appropriate economic incentives and training for farmers are required to implement innovative approaches.

Highlights

The main cultivated crops in northeast Syria are wheat and cotton
beneficial water use fraction (BWUF), resulting in water savings varying from to to lower gross irrigation depth (GID) (Figure 9a), due to higher BWUF, resulting in water savings varying from 11% to 34%
Since GID is smaller for sprinkler systems, assuming that yields are similar for both surface and sprinkler systems, it results in larger water productivity (WP of 0.97–0.99 kg·m−3 ) for the latter (Figure 9b)

Summary

Introduction

The main cultivated crops in northeast Syria are wheat and cotton. Wheat (Triticum durum and T. aestivum L.) was originated in the Fertile Crescent region, which comprises northeast Syria, around 10,000 years B.C. The largest wheat cultivated area, representing 39% of the total country production (45% irrigated and 55% rainfed), was the Al-Hassakeh Governorate, in the Al-Khabour basin, northeastern Syria [2]. Water scarcity has gradually increased in the last few years due to excessive overdraft of the groundwater in both Syria and Turkey [3,4,5,6,7], as well as due to climate change [8]. To face the related problems, a national irrigation modernization project has been implemented [9,10,11]. All efforts were destroyed by the on-going war, preparing for peace is paramount

Methods

Results

Conclusion