جستجوی مقالات مرتبط با کلیدواژه « Tillage method » در نشریات گروه « آب و خاک »

This research was performed to improve water productivity by changing a number of farmers' field practices such as tillage, dimensions of the irrigation borders, using newly released plants varieties, and improving fertilizer management in eight farms located in the Oskoo, Ajabshir, and Bonab cities, all parts of the eastern Uromieh Lake Basin, during 2015-2016 growing season. The adopted farm practices were applied in the treatment farms, while in the control farms, all the farming operations were implemented according to the local traditional practices. In all farms, the flow rates diverted to each farm, the soil moisture content in the root zone during the growing season, and indices related to the growth and yield of crops were measured. The indices of water productivity (WP), water use efficiency (WUE) and water economic productivity (WPe) were calculated. Water consumption was lower up to 9% while crops yields of the treatment farms were higher up to 34%, as compared with the control farms. According to the results, on average, implementation of applied technologies in the treatment farms increased WP, WUE, and WPe by 38%, 31%, and 56 %, respectively, as compared to the control farms.

The availability of water is the most important factor controlling the soil productivity in arid and semi-arid regions. In this area, crop yield is strongly affected by precipitation and water retention in the soils. The application of soil management practices can be suitably control surface runoff and enhance water retention in soil. Tillage as the major tool of soil management practices can affect the runoff production and soil erosion and so can influence the availability of water and crop yield in the rainfed lands. Yet, in most semi-arid areas, rainfed lands are ploughed up and down slope, a practice that decline water retention by declining the opportunity of water infiltration in to soil. Although various studies have been done to determine the effect of tillage methods on water conservation and crop yield worldwide, little information is available on the role of plough direction on the water retention and crop yield in wheat rainfed lands in semi-aria areas, particularly in Iran. Therefore this study was conducted to determine the effects of two plough directions (up and down slope and contour line) on soil water content during the growth period and grain yield of wheat in a semi-arid rainfed land in Iran.
The study was carried out in a rainfed lands with slope steepness of 10 % and clay loam soil in west of Zanjan, north western Iran in 2015. Winter wheat was cultivated in two directions consisted of 1) up and down slope (as conventional tillage) and 2) contour line (as conservation tillage) early October 2014. A total of twenty four plots, with 1.75 m  8 m dimensions were designed on the land after cultivation. Soil water content was determined in three core samples taken from the rhizosphere in each plot in 5-day interval during the growth period from October 2014 to Jun 2015. Grain yield and yield components of wheat were determined by collecting all crops of plot surface at the harvesting time (Jun). Analysis of variance and the Duncan’s test were conducted for data of soil water content and grain yield of wheat. Statistical analysis was conducted using SPSS 21 software.
Mean soil water content during the growth period in the contour plots (9.1%) was 62% more than the up and down slope plots (5.6%). This difference was statistically significant (p This study showed that the plough direction is the major factor controlling soil water content in rainfed wheat farms. In the plots ploughed on the contour line, the opportunity of rainwater to infiltrate into the soil is very high. This factor is the most important factor controlling wheat yield under rainfed condition. Increased wheat grain yield under the contour lines cultivation could be attributed to increase in yield components which in turn were influenced by increase soil water content. With regarding these results, application of contour line ploughing method in the rainfed lands of sloped area could be substantial strategy to decline water loss and enhance crop yield in semi-arid regions.