Investigation of Irrigation Water and Water Productivity of Pomegranate Orchards in Iran

It is necessary to study of water productivity of pomegranate orchards because of limited water resources, need to improve water productivity and the importance of pomegranate fruit. In this study, the volume of applied water and pomegranate yield in more than 120 selected orchards in the provinces of Isfahan, Khorasan Razavi, Markazi, Semnan, Yazd and Fars were measured. Analysis of variance was used to investigate the possible differences in yield, applied water and water productivity. Results showed that except for yield, the difference in the applied water and water productivity was significant. The average yield of pomegranate was 21.5 ton/ha. The average volume of applied irrigation water was 14792 m3/ha. The average productivity of applied irrigation water was 1.69 kg/m3. The average water + effective long-term rainfall productivity was 1.47 kg/m3. The productivity of water + effective rainfall of the current year was 1.43 kg/m3. The volume of applied water in pomegranate orchards and the gross water requirement was not similar in the selected provinces. In some provinces such as Fars, Khorasan Razavi, Semnan and Markazi, the volume of applied water was less than the gross water requirement and in Isfahan and Yazd provinces was more than the gross water requirement. But on average, the volume of applied irrigation water was close to the gross water requirement in the year of the research and to the long-term gross water requirement. The average volume of applied water in drip and surface irrigation systems was 9981 and 15765 m3/ha, respectively, the percentage of reduction of applied water in drip irrigation system compared to surface irrigation was 37%.