Ranking Evaluation of Drip Irrigation and Perforated Low-Pressure PVC Pipes Systems in Pistachio Orchards of Kerman Province Based on the Non-Linear Optimization Decision Model

The importance of pistachio production and water resource shortage in Iran reveals the necessity of irrigation system selection, as an important driving-force to upgrade agricultural. Therefore, ranking evaluation of irrigation systems in pistachio orchards is considered as a practical and useful problem in the water and economic fields. In the present study, a multi-criteria decision-making approach as integrated method of grey relational analysis-TOPSIS-Entropy (GRA-TOPSIS-Entropy) was applied for ranking of modern pressurized systems in pistachio orchards. The results of GRA-TOPSIS-Entropy method were compared with ranks of systems from principal component analysis (PCA). For this purpose, 7 surface drip irrigation systems, 4 subsurface drip irrigation systems, and 2 perforated low-pressure PVC pipes systems in the pistachio orchards of Kerman province were assessed and ranked. The evaluation was processed using important quantity and quality variables of leaf area, new branch length, yield, percentage of blank nuts, percentage of split nuts, pistachio ounce, and water use efficiency. The mean ultimate decision index of surface drip irrigation, subsurface drip irrigation, and perforated low-pressure PVC pipes systems using GRA-TOPSIS-Entropy method were equal to 0.57, 0.52, and 0.51, respectively that had not significant difference. The results indicated that surface drip irrigation and perforated low-pressure PVC pipes systems are the optimal systems in the studied area. The results of discrimination degree as an index for investigating stability and reliability of GRA-TOPSIS-Entropy and PCA methods calculated as 1.10 and 1.08 that showed the ranking results are reasonable. Based on the achieved results, the integrated GRA-TOPSIS-Entropy method with strong mathematical and non-linear optimization background can be useful to select appropriate pressurized irrigation systems in pistachio orchards.