Optimization of Irrigation Water Distribution Using the Mga Method and Comparison With a Linear Programming Method

Abstract

Optimization of irrigation water distribution is an important item for water management in irrigation networks. A linear programming model can have problems, for example when the objective function is based on only one goal. So some methods, for example modelling to generate alternatives (MGA), can improve results. This study presented a schedule for distributing irrigation water as well as an optimal cultivation pattern aiming at maximizing net profit on one side and water productivity (WP) on the other. Since the production function is the most important part of water distribution models, the best available production functions were checked and calibrated. The obtained results revealed that WP could be enhanced by 20-40% using the MGA technique. However, investigation of water shortage conditions showed that a 30-35% water deficit could result in an increase of WP by 54%. Thus, it could be argued that the most important matter in water management in irrigation networks is the simultaneous study of WP and water economic productivity (WEP). Considering both factors, a deficit of 30%, which results in a decrease of profit by 10%, was selected as the best alternative for the economic enhancement of WP in the Qazvin Plain. Copyright © 2014 John Wiley & Sons, Ltd. RÉSUMÉ L'optimisation de la distribution de l'eau d'irrigation est l'élément important pour la gestion de l'eau dans les réseaux d'irrigation. Un modèle de programmation linéaire peut avoir quelques problèmes, quand, par exemple, la fonction objective est basée sur un seul but. Donc, une méthode, comme la modélisation pour générer des alternatives (MGA), peut amener une amélioration. Cette étude présente un calendrier pour la distribution de l'eau d'irrigation ainsi que d'un modèle de culture optimale visant à maximiser le bénéfice net d'un côté et la productivité de l'eau (WP) de l'autre. Puisque la fonction de production est la partie la plus importante de modèles de distribution d'eau, les meilleures fonctions de production disponibles ont été vérifiées et étalonnées. Les résultats obtenus ont révélé que WP pourrait être améliorée de 20-40 % en utilisant la technique MGA. Toutefois, l'enquête des conditions de pénurie d'eau a montré qu'un déficit en eau de 30-35% pourrait se traduire par l'augmentation de WP de 54%. Ainsi, on pourrait faire valoir que la question la plus importante dans la gestion de l'eau dans le réseau d'irrigation est l'étude simultanée de WP et l'efficacité économique de l'eau (WEP). Considérant les deux facteurs, un déficit de 30%, qui se traduit par la diminution du bénéfice de 10%, a été choisi comme la meilleure alternative pour le renforcement économique de WP à Qazvin Plain.

Optimization of water and land allocation in salinity and deficit- irrigation conditions at farm level in Qazvin plain

“…In addition, the introduction of three type CWPFs can also include impacts of climate uncertainty into the objective functions, and the economic risks could be provided in optimization. Therefore, model could be more reasonable with considering above mentioned as compared with the previous regional optimization models [28,29].…”

“…The results of the present study, like previous studies, indicate that the amount of net profit in saline soils is affected by salinity; the higher soil salinity is, the lower the final profit will be [11][12][13][14] That also reduces water productivity. Tafteh et al [29] also showed that water productivity increases by applying deficit-irrigation. The increase in water productivity in all three soil types due to deficit-irrigation is illustrated in Fig 7 . According to Fig 8, considering reasonable variation in economic profit as compared in current situation, the amount of profit at 20% of irrigation water stress were seen.…”

“…Basin irrigation method was used. According to the available information, the irrigation efficiency of the region was considered to be 35% [29]. The planting date of the crops and the soil properties are presented in Tables 1 and 3, respectively.…”

A Review of Applications of Linear Programming to Optimize Agricultural Solutions

“…A study by [38] presented a plan for irrigation water distribution and an optimum planting pattern to optimize the net income and increase water productivity (WP). They showed that linear optimization with maximum benefit results gives the lowest water productivity.…”

Basil root water uptake derived models under combined water and nitrogen deficit conditions

“…In arid and semi-arid regions like Iran, not only are we faced with the limitations of quality and quantity of water resources, but also with the low fertility of the soil (Sarai et al, 2012;Babazadeh and Sarai Tabrizi, 2013;Tafteh et al, 2014). Therefore, water and nitrogen are the important effective limiting factors in crop production in arid and semi-arid regions.…”