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The worsening water scarcity has imposed a significant stress on food production in many parts of the world. This stress becomes more critical when countries seek self-sufficiency. A literature review shows that food self-sufficiency has not been assessed as the main factor in determining the optimal cultivation patterns. However, food self-sufficiency is one of the main policies of these countries and requires the most attention and concentration. Previous works have focused on the virtual water trade to meet regional food demand and to calculate trade flows. The potential of the trade network can be exploited to improve the cropping pattern to ensure food and water security. To this end, and based on the research gaps mentioned, this study develops a method to link intra-country trade networks, food security, and total water footprints (WFs) to improve food security. The method is applied in Iran, a water-scarce country. The study shows that 781 × 106 m3 of water could be saved by creating a trade network. Results of the balanced trade network are input to a multi-objective optimization model to improve cropping patterns based on the objectives of achieving food security and preventing water crises. The method provides 400 management scenarios to improve cropping patterns considering 51 main crops in Iran. Results show a range of improvements in food security (19-45%) and a decrease in WFs (2-3%). The selected scenario for Iran would reduce the blue water footprint by 1207 × 106 m3, and reduce the cropland area by 19 × 103 ha. This methodology allows decision makers to develop policies that achieve food security under limited water resources in arid and semi-arid regions.

The aim of this research was to measure wetting front (WF) advances under various conditions using a physical model. WF advance, along with its distribution in soils, is an important parameter in drip irrigation. It is influenced by many factors, including land slope, emitter discharge and soil texture. The effects of these factors were investigated by constructing a physical model (60 cm wide, 120 cm high and 160 cm long). Experiments were conducted using two heterogeneous soils, three land slopes (0, 10 and 20%), three emitter discharges (2, 4 and 8 l/h) and a constant volume of irrigation water (24 l). The results indicated that, on sloping lands, the wetted area of the WF advance downstream from the emitter was, on average, 20–62% greater than that upstream from the emitter. With an increase in land slope, the wetted depth under the emitter decreased by 3–18%. When the land slope was changed from 0 to 10% and then again from 10 to 20%, the maximum radius of the WF increased, on average, by 32, 44.8 and 77.5% for discharges of 2, 4 and 8 l/h, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Six plots include three plots of solid-set sprinkler and three plots of border irrigation methods in Kangavar plain (Iran), were evaluated under farmers' management standards. Wheat was grown in each of the plots and all the irrigation events were evaluated. The average values of irrigation indexes, distribution uniformity, potential application efficiency of the low quarter, application efficiency of the low quarter, application efficiency, deep percolation ratio, adequacy of irrigation, and water requirement efficiency in border-irrigated plots were 80.4%, 80.4%, 69.1%, 80.5%, 19.5%, 53.1%, and 80.8%, respectively. Those values indicated much better performance than the average values for the movable solid-set sprinkler-irrigated plots, which were 55.8%, 44.7%, 37.2%, 41.5%, 38.6%, 85.0% and 96.5%, respectively. So the system design and the farmers' management are suitable with border irrigation in accordance with the experiences they have gained with time. That was not the case for the movable sprinkler irrigation system, in which the performance indexes are below the recommended minimum values. Therefore, the efficiency of an irrigation system is not independent of its management, and the farmer's skill on the irrigation system is one of the most important indices for selecting a suitable irrigation system. Also, improving farmer's management is the most appropriate way for improving irrigation performance. [ABSTRACT FROM AUTHOR]

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)