aliasghar aghabeigi; Mohammad Ali Gholami Sefidkouhi; mahmoud raeini; Mohammadreza Yazdani
Abstract
Management of soil and water resources and sustainable development of agriculture by increasing rice yield and water productivity has high importance. Consolidation of paddy fields is one of the solutions for this purpose. In this regard, this research aimed to investigate role of consolidation projects ...
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Management of soil and water resources and sustainable development of agriculture by increasing rice yield and water productivity has high importance. Consolidation of paddy fields is one of the solutions for this purpose. In this regard, this research aimed to investigate role of consolidation projects in paddy fields on water productivity. The research was done in Astaneh Ashrafiyeh, in Guilan Province, on paddy fields in 3 situations (upland, middle land, and lowland) and 2 farm types (traditional and consolidated), with 5 replications, during 2015 and 2016 . The data on rice yield and different water productivities were analyzed based on double split plot with Tuckey mean analysis method. The results showed that average yield of traditional and consolidated fields were 3958 and 3901 kg ha-1, respectively, without any significant difference. In traditional fields, the gross productivity based on evapotranspiration alone and evapotranspiration plus percolation was, respectively, 3% and 3 % more than those in the consolidated fields. However, net productivity based on evapotranspiration alone, evapotranspiration plus percolation, and water use in consolidated fields was, respectively, 50%, 51%, and 54% more than in traditional fields. Therefore, planning and implementing consolidation projects on paddy fields can increase water productivity.
aliasghar aghabeigi; Mohammad Ali Gholami Sefidkouhi; mahmoud raeini; mohammadreza yazdani
Abstract
Rice is the second most important staple food after wheat in the world, and Iran has an annual production of 2 M tons. Due to water scarcity problems and high water consumption in paddy fields and the need to increase irrigation water productivity, a lot of paddy fields are consolidated in the Northern ...
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Rice is the second most important staple food after wheat in the world, and Iran has an annual production of 2 M tons. Due to water scarcity problems and high water consumption in paddy fields and the need to increase irrigation water productivity, a lot of paddy fields are consolidated in the Northern provinces of Iran every year. In consolidation projects, soil is displaced by leveling practice, and then the content of soil chemical elements will be changed. This study was aimed to investigate the role of consolidation projects in paddy fields on soil and drainage water quality. The research was conducted in Astaneh Ashrafiyeh in Guilan Province on traditional and consolidated paddy fields in 3 situations (upland, middle land, and lowland) with 5 replication, in 2016. The soil and outlet/drainage water chemical properties were analyzed based on split plot design with Tucke’s mean analysis method. The soil physical and chemical characteristics results showed that the amount of SAR, Cl, NO 3 and SO 4 in consolidated fields were significantly different than that in traditional fields. The amount of SP and OC of soil in consolidated fields were, respectively, 22% and 11%, more than that in traditional fields, and available potassium was 2% less than traditional farms. Also, the amount of SAR and Cl and NO 3 of outlet water in consolidated fields were, respectively, 14%, 23%, and 49%, more than that in traditional fields. All soil mineral components, other than clay, land had less uniformity in levelled lands than traditional lands. Uniform distribution of mineral components in levelled lands can be effective in improving irrigation and nutrition management of plants. In addition to infrastructural changes, the leveling of rice paddies also causes changes in physical and chemical conditions of the soil, as well as changes in the quality of drainage water, which should be considered in agricultural management and reuse of outlet drainage water in downstream farms.
m a; p a; m y; a l; m d
Abstract
A second crop in paddy fields has economic advantages resulting from the production of crops (canola, beans, garlic, triticale, soybean, etc.), Preparation of rice bed for mechanized harvesting, strengthening the economy of farmers’ families, increase the incentive for farmers to stay in the village, ...
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A second crop in paddy fields has economic advantages resulting from the production of crops (canola, beans, garlic, triticale, soybean, etc.), Preparation of rice bed for mechanized harvesting, strengthening the economy of farmers’ families, increase the incentive for farmers to stay in the village, etc. Due to the inability of the existing surface drainage systems in rapid depletion of water from the root zone, conditions for planting a second crop in paddy fields is not suitable. This can be provided by installing subsurface drainage systems, which, in addition to creating more favorable conditions for planting and harvesting rice, allows cultivation of other crops in the wet season. This research was conducted to determine the appropriate space and depth of subsurface drainage in paddy fields in order to provide favorable conditions for planting a second crop. The experiment was laid out in one and a half hectares of paddy fields at Rice Research Institute of Iran in Guilan province, in 2014. Drainage treatments included: six conventional subsurface drainage systems with rice husk envelope including drainage system with different drain depth and spacing L7.5 D0.8, L10 D0.8, and L15 D0.8, L7.5 D1, L10 D1, and L15 D1, surface drainage, and the control (without drainage). All lines were 40 meters long and made of PVC corrugated pipes with a diameter of 125 mm. Rice husk was used as a covering around the pipe drain. The results showed that subsurface drainage spacing of 15 m had failed to lower the water table depth to an acceptable level and provided the conditions only for the cultivation of shallow-rooted plants such as dill, parsley, and leeks. Also, surface drainage could reduce the excess water in the soil by 22% compared to control. To provide suitable conditions for the cultivation of second crops such as canola and beans, subsurface drainage spacing of 7.5 and 10 m seemed effective. However, to avoid excessive drainages by 7.5 m spacing, subsurface drainage spacing of 10 m was selected as the best space at drainages stage, for a second crop. Furthermore, due to the lack of significant differences in water table depth between treatments L10D1 and L10D0.8,theywere identified as suitable drainage systems at 0.8 m depth.