جستجوی مقالات مرتبط با کلیدواژه « modern irrigation systems » در نشریات گروه « آب و خاک »

Irrigation efficiency is one of the most important key indicators in the macro-planning of water supply, allocation, and basic water consumption in various sectors such as industry, drinking, environment, and other biological resources, especially agriculture. In many countries such as Iran, irrigated agriculture is the main factor in food production and irrigation has played a key role in increasing the production of agricultural products in the last 50 years. One of the biggest problems for wheat production is the need for more water resources. Therefore, the necessity of optimal use of available and extractable water resources and increasing water consumption efficiency is inevitable. Experiments and experiences of the last half century in the science and technology of irrigation have shown that the effect of various inputs such as modified seeds, chemical fertilizers, appropriate planting operations, and harvesting has a positive and appropriate effect on plant growth. Irrigation management, which includes a set of actions that provide water in a certain amount and at the required time to the plant, must be done in a good way.

The current study has targeted the main areas of wheat production in Iran. Due to its high nutritional value and strategic importance, wheat is cultivated in almost all areas of the country. According to the Pareto principle, the areas where 80% of wheat cultivation and production (irrigated and rainfed) are carried out are the main wheat production areas. Since in Iran, the statistics of the agricultural situation are mainly presented based on political divisions, therefore, the major regions will be the set of provinces in which the above hypothesis is true. Accordingly, 13 provinces of Golestan, Kermanshah, West Azarbaijan, East Azarbaijan, Hamedan, Ardabil, Lorestan, Central, Khuzestan, Fars, Razavi Khorasan, Kurdistan, and Zanjan have been identified as the main wheat production areas in Iran and in this study also, the main focus was on these areas. Since the vast country of Iran has a diverse climate, to ensure that all the country's climate groups are represented in the selected regions, an adaptation of these regions to the country's climate groups was also done.

The comprehensive analysis indicated that the area proposed for implementing the drip irrigation system (tape) in 2020-2021 was equal to 75,000 ha, of which 53,523 ha (71.4%) belong to the 13 main producing provinces or the main wheat production areas. Also, the results showed that the reduction of agricultural water consumption with the development of a drip irrigation system in the main wheat production areas leads to a reduction of 134.1 million m3 of agricultural water. The implementation cost of this solution based on the average implementation of each ha of drip irrigation system is 400 million Rials in the year 2021, equal to 21409 billion Rials. Among the limitations of wheat irrigation with the tape method, we can point out the spreading and distribution of tapes in the field, which is time-consuming, but with the introduction of sowing and distribution devices, this problem will be solved. At the beginning stage, care should be taken not to tear the tapes during the spraying and fertilizing stage. In the harvesting phase, before harvesting the crop, tapes should be collected from the field. In the whole system, strip drip irrigation (type) can be used for dense and row crops such as all kinds of vegetables, summer crops, corn, wheat, fodder, watermelon, melon, tomato, onion, potato, strawberry, sunflower, sugar beet, and cotton.

One of the pressurized irrigation methods that have been developed for wheat cultivation in recent years is the drip (tape) irrigation system, most of the research and field investigations in Iran have confirmed the high efficiency of this method in increasing wheat water productivity. As a result, using the modern irrigation system as a management tool can lead to the improvement of wheat water productivity in Iran. The main problem in this system is the high cost and low knowledge of the farmer. We can also mention the weak points of increasing the cost of constructing the irrigation system, the problems of collecting strips for the next crop, and the accumulation of salt in areas with salty water. Among the strengths, we can mention easier irrigation management, less labor, increased yield, reduced water consumption, increased productivity, and most importantly, increased cultivated area with the same amount of water. Another advantage is the use of the water-fertilizer system, which will be very precise, the operation of fertilizing and irrigation will be done for cultivated crops.

This research aimed to select essential features for modeling the cost of pressurized irrigation systems using the data of 515 drip irrigation projects in four parts, including the cost of pumping station and central control system (TCP), cost of on-farm equipment (TCF), cost of installation and operation on-farm and pumping station (TCI), and total cost (TCT). In the first stage, a database including 39 features influencing the cost of the mentioned sectors was prepared and the price of all projects (2006 to 2019) was updated for the base year of 2021. Then, feature selection was done with different algorithms in MATLAB environment and in two parts including (1) all features (39 features before and after the design stage) and (2) 18 features before the design phase (BD). The results showed that the amounts of RMSE and R2 for all the features were equal to 0.007 and 0.92, respectively, and for the BD section, they were equal to 0.003 and 0.89, respectively. Among the different algorithms for feature selection, support vector machine (SVM) and optimization algorithms (Wrapper) were identified as the best learner and feature selection method, respectively. The results of the evaluation criteria showed that the two LCA and FOA algorithms achieved the best estimation, and their error criterion in all the features were 0.0020 and 0.0018, respectively, while their correlations were 0.94 and 0.94. In the BD features, these criteria were 0.0006 and 0.95 for both algorithms, respectively. Finally, in the all features section, 10 out of 39 features and for BD section, 8 out of 18 were selected as the most effective features. The results of choosing the most effective features that affect the cost of different parts of the drip irrigation system can make the cost modeling of the systems simpler and faster and, while being useful for research works, it facilitates estimation and management of costs before implementation of each project.

The use of modern irrigation methods, deficit irrigation, the use of cultivars more resistant to drought stress, are ways to increase water use efficiency in agriculture. To study the effect irrigation level and type of maize cultivar on water use efficiency in forage and grain maize production, this research was conducted at the research farm of Agricultural and Natural Resources College of University of Tehran (Karaj) in 2017. The main treatments included two levels of irrigation (100 and 80% of maize water requirement) in subsurface drip irrigation system; sub-treatments included three maize cultivars KSC704, KSC600, KSC400. Experimental design was based on split plots based on randomized complete blocks. The studied traits were forage yield, biomass, grain, water use efficiency in forage, biomass and grain production, 1000-grain weight and harvest index. The results showed that the effect of irrigation level on the measured traits was insignificant and the effect of cultivar on them was significant at both irrigation levels. The highest amount of water use efficiency in biomass production was 4.37 kg / m3 in KSC600 cultivar and the highest water use efficiency in grain production was 2.43 kg / m3 in KSC704 cultivar (with KSC400 cultivar in a Statistical group) obtained at the irrigation level of 80%. Also, KSC400 cultivar, being in the common statistical group with KSC704 cultivar, had the highest 1000-grain weight of 537.3 grams. Deficit irrigation up to 80% of water requirement using subsurface irrigation system had not any significant effect on the yield of maize cultivars.

Increasing water productivity is one of the mechanisms for water use management, and economic methods such as water pricing, are one of the solutions that reduce water consumption and increase water productivity. In this research, the impact of water pricing on increasing the water productivity in the irrigation network of Qazvin plain by the aid of modern irrigation systems was investigated. Therefore, regarding existing information comprised of network construction costs, ongoing costs and other expenditures, the cost for per cubic meter of water in the irrigation network of Qazvin plain was estimated based on the engineering economics method in 2018. Then, according to the cropping pattern of the network, the net irrigation requirement of each crop and its associated costs and incomes, the economic productivity of each crop was investigated regarding to four different scenarios The results illustrated that the price of water sales in the irrigation network is much lower than its real price. Water pricing in irrigation network due to a rise in farming costs has led to encouraging farmers to implement modern irrigation systems as well, and consequently resulted in a reduction in water consumption and increased water productivity in the irrigation network of Qazvin plain. Thus, if farmers implemented modern irrigation systems in their fields, economic water productivity in the network would increase and the government could sell the water to the farmers at a realistic price.