Irrigation
A.R. Kiani; M.R. Yazdani; M.T. Feyzbakhsh
Abstract
Introduction: In Golestan province, despite the lack of water resources, traditional rice cultivation, a crop with high water consumption, is increasing due to economic justification. This issue has become one of the main problems of the province's agricultural sector in recent years. In order to prepare ...
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Introduction: In Golestan province, despite the lack of water resources, traditional rice cultivation, a crop with high water consumption, is increasing due to economic justification. This issue has become one of the main problems of the province's agricultural sector in recent years. In order to prepare the planting bed (puddled transplanting) in the traditional method of rice production, a significant amount of irrigation water is used before planting the seedlings in the main land. Moreover, the plant is in the water during the growing season, which causes high water losses by surface water evaporation and deep penetration. Rice direct seeding cultivation is a method that has been considered in the world for various reasons, including higher water productivity. Currently, reports indicate that more than 50% of groundwater resources are extracted and allocated annually for rice cultivation in the region investigated. In general, field information and observations indicate that the level of paddy cultivation is increasing in the province. In the past few decades, agricultural policymakers have sought to restrict and ban rice cultivation in the country, except in Gilan and Mazandaran provinces. The rationale behind this decision is high water consumption, declining groundwater aquifers and long-term instability of water resources. The developed strategy did not work effectively, as it did not consider the benefits of the farmers in the short run. The increasing trend in the area under paddy fields from 1995 to 1500 hectares per year shows the unsuccessfulness of this up-to-down strategy.Materials and Methods: A field experiment was conducted to investigate the effect of rice cultivation and irrigation methods on yield, water consumption and water productivity over two rice cropping seasons (2019–2020) in northern Iran (Gorgan Agricultural Research Station). Irrigation method as the main factor in four levels (permanent flooding, intermittent as wet and dry, sprinkler, tape) and cultivation method in three levels (direct seed in dry bed, non-puddled transplanting and traditional transplanting) in the form of a strip design. The plot was based on a randomized complete block design with three replications. The applied water, yield and some yield components and water productivity were measured and calculated during the growing seasons.Results and Discussion: The results showed that in all irrigation methods, yield was significantly reduced by changing the traditional seeding transplanting to dry seed. The amount of water applied in sprinkler and drip irrigation methods from traditional seedlings was significantly reduced as compared to direct seed seeding. Dry seed cultivation, however, consumed more water than traditional transplanting in the flood irrigation treatments (wet and dry and permanent). The highest yield (8206 kg/ha) was obtained for traditional seedling cultivation by flood irrigation, and no significant difference was observed between the yields for the other irrigation methods. In general, changing the irrigation systems had a greater effect on water consumption than changing the rice cultivation method. In addition, changing the cultivation method had a greater effect on changing the type of irrigation systems. In traditional transplanting cultivation, the yield decreased by about 14, 9 and 11%, respectively, by changing the irrigation systems from permanent flood irrigation to sprinkler, wet and dry, and drip irrigation. The highest water use was observed for flood irrigation method in direct seeding (12490 m3/ha) and direct transplanting (11967 m3/ha).Conclusion: Currently, farmers cultivate rice by transplanting in padded land irrigated by flooding techniques in Golestan province, which results in high water consumption (about 13,000 m3/ha). By changing the irrigation method from flood irrigation to drip for traditional transplanting cultivation, water consumption decreased by about 39% and as a result water productivity increased by about 22%, albeit a 11% reduction in yield occurred. With the conversion of traditional transplanting seedling by flood irrigation to non-puddled transplanting by drip irrigation, the yield decreased by about 24% and the amount of water by about 45%, and water productivity in this case reached 0.9 kg/m3. This can be considered as the best alternative for conserving both water resources and production. If only reducing water consumption is the main priority (regardless of yield reduction), the best treatments are drip irrigation with direct seeding, non-puddled transplanting and then traditional seedling, respectively. If there is a sprinkler irrigation system in the field, this option is given priority in the direct seeding and non-puddled transplanting. If changing the irrigation system is not considered, the use of intermittent irrigation (as a wet and dry) with non-puddled transplanting, traditional methods and direct seeding are preferred, respectively.
S.H. Tayebnia; S. Darini
Abstract
Introduction: Reducing water resources in the country and increasing water loss in different methods of irrigation have increased oriented the attention to pressurized irrigation, especially drip irrigation. One of the most suitable solutions for proper water resources management in the country is applying ...
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Introduction: Reducing water resources in the country and increasing water loss in different methods of irrigation have increased oriented the attention to pressurized irrigation, especially drip irrigation. One of the most suitable solutions for proper water resources management in the country is applying drip irrigation system in gardens. The village of Mohammad Abad is located in the central part of Anbarabad Township and has 15 villages. The main economic activity is horticultural practices there. Water losses due to soil evaporation are minimized in pressurized irrigation due to the decrease in the level of soil wetting, as well as the loss of water distribution in the air or soaking the foliage by this method. The use of this method reduces the growth of weeds and, consequently, unwanted water consumption by weeds, which ultimately affects the various aspects of rural life in the area. The purpose of this study was to investigate the effects of new irrigation systems on villagers in Mohammad Abad village. Therefore, this research sought to answer the question of what are the consequences of new irrigation systems in the rural areas of Mohammad Abad. Materials and Methods: The research method was based on the applied objective and descriptive-analytic based on the method used. To collect the information in the theoretical part of the documentary resources, in the practical section, a survey method based on the distribution of the questionnaire and direct observation was used. The statistical population of the research was Mohammad Abad village with 15 villages, 1113 households and 5358 people. The four villages including 300 households and 955 people which employed modern irrigation systems were sampled. Next sampling was based on the number of households. According to the research facilities, 50% of households was selected as 150 households. Then, the questionnaires were distributed randomly among the households' supervisors of the village to the number specified, which was allocated according to the population of each village. In the present study, SPSS software was used to analyze the data and Pearson correlation coefficient and regression analysis and one-sample T-test were used to measure the variables. The information gathering tool was a researcher-made questionnaire. Results and Discussion: Based on the results, the highest employment in the agriculture and horticulture sector was at 45.3%, which is due to the climate of the surveyed community, and the land inheritance laws. The lowest employment rate was in the administrative and service sector with an average of 5.3%. Moreover, according to the table below, 94.7% of owners have new and drip irrigation systems. Additionally, 13 items were considered to investigate the effect of new irrigation systems on villagers' life. All items were achieved a weighted average and higher score. According to the items studied, the target issue was related to increasing the household welfare (3.78), quantitative and qualitative products (3.76), increasing household welfare (3.78), improving quality of life (3.65), reducing the motivation of immigration (3.49) , increase in product quality (3.93), reduction of irrigation problems (4.48), water saving (4.49), increase in the economic situation of people (3.65), increase in production efficiency (3.78), return of immigrants (3.61), reclamation of abandoned lands (4.46) which all were above-average. Overall, the economic status as a general indicator with average of 3.90 was also above-average. In addition, there was a positive and significant correlation between all variables with new irrigation systems. Thus, new irrigation systems have had a positive impact on the improvement of all variables. The income increase, return of migrants and increase in efficiency of production seem to be more useful variables for predicting the rural population's economic status. Conclusion: Based on the results, applying traditional irrigation increased irrigation costs and reduced the production efficiency and the quantity and quality of production in our studied region. Modern irrigation has had a positive effect on the economic and social condition of the villagers leading to increased revenues. Consequently, this has resulted in the restoration of the abandoned lands and the return of migrants. The results also show that the use of new irrigation systems, in addition to reducing water losses, will increase household income, product quality and the level of welfare and quality of life, reduce migration, and restore the deserted lands.
