فهرست مطالب

آبیاری و زهکشی ایران - سال یازدهم شماره 6 (بهمن و اسفند 1396)

مجله آبیاری و زهکشی ایران
سال یازدهم شماره 6 (بهمن و اسفند 1396)

  • تاریخ انتشار: 1397/01/08
  • تعداد عناوین: 6
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  • مقاله پژوهشی
  • صابر جمالی*، حسین شریفان، فراست سجادی صفحات 935-946
    از آن جایی که بخش کشاورزی عمده ترین مصرف کننده ی منابع محدود آبی کشور است، به کارگیری روش هایی به منظور افزایش راندمان کاربرد آب در این بخش امری ضروری است. از راهکارهای مقابله با بحران آب استفاده از آب های نامتعارف در کشاورزی می باشد. به منظور بررسی اثر آبیاری با روش تلفیق آب دریای خزر و آب شیرین بر عملکرد و اجزای عملکرد گیاه جعفری آزمایشی در قالب طرح کامل تصادفی با 4 تیمار (اختلاط آب دریای خزر با آب شهری، آبیاری یک در میان با آب دریا و آب شهری، آبیاری نیم در میان آب دریا و آب شهری، آب شهری) تحت شرایط گلخانه ای در دانشگاه علوم کشاورزی و منابع طبیعی گرگان با سه تکرار در زمستان سال 1393اجرا شد. نتایج نشان داد که رژیم های مختلف آبیاری بر وزن تر و خشک ریشه، ارتفاع ریشه، ارتفاع بوته و وزن خشک اندام هوایی در سطح احتمال یک درصد معنی دار بوده ولی بر وزن تر اندام هوایی و تعداد برگ در هر بوته در سطح احتمال پنج درصد معنی دار بود. تیمار متناوب نیم در میان، متناوب یک در میان و اختلاط آب دریا منجر به کاهش 7/28، 4/26 و 8/55 درصدی عملکرد شد
    کلیدواژگان: آب نامتعارف، اختلاط آب دریای خزر، تلفیق آب شور و شیرین، جعفری، متناوب نیم در میان
  • شیدا دهقان*، نسرین سیاری، بهرام بختیاری صفحات 947-959
    خشکسالی از بلایای محیطی است که فراوانی آن به ویژه در نواحی خشک و نیمه خشک بسیار زیاد می باشد .امروزه شاخص های خشکساالی باه عنوان ابزاری مناسب برای اقدامات مدیریتی و به دنبال آن مقابله با پدیده ی خشکسالی، به طور وسیعی در دنیا مورد استفاده قرار می گیرند. یکی از این شاخص ها، شاخص شدت خشک سالی پالمر (PDSI ) است که در بسیاری از نقاط جهان جهت بررسی شرایط خشکسالی و تداوم آن مورد استفاده قرار گرفته است. در این مقاله وضعیت خشکسالی استان فارس با استفاده از این شاخص طی دوره ی آماری 20 ساله (1995-2014) و با توجه به داده های هواشناسی 6 ایستگاه هواشناسی مختلف استان فارس مورد ارزیابی قار گرفت. نتایج نشان داد سال 2010 برای ایستگاه های آباده ، داراب، فسا و سال 2001 برای ایستگاه های اقلید و لار در سال 1996 برای ایستگاه شیراز خشک ترین سال ها در بازه ی آماری 2014-1995 بودند. در این بازه ی زمانی در ایستگاه ها تغییرات بارش نیز مشاهده شد که در سال های ذکر شده برای شدیدترین خشک سالی ها افت بارش مشاهده شد. البته در تمام ایستگاه ها در سال 2010 افت شدیدی در بارش وجود داشت که نشان دهنده ی وضعیت خشکی در این سال بود.
    کلیدواژگان: ایستگاه هواشناسی، بارش، رطوبت خاک، روندیابی، فارس
  • جعفر مهرآبادی، بیژن قهرمان، کاظم اسماعیلی * صفحات 960-971
  • حجت احمدی *، سمیرا مردعلی، ثمر بهروزی نیا صفحات 972-987
  • اکرم عباسپور *، داود فرسادی زاده، محمدرضا عبدیان رکنی صفحات 988-998
  • یاسمن بلادی*، محمود شفاعی بجستان صفحات 999-1008
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  • Saber Jamali *, Hossien Sharifan, Ferasat Sajadi Pages 935-946
    Since the agriculture field is the main water consumer, using techniques in order to increasing water use efficiency is necessary. Another method to counter water crisis is using unconventional water in agriculture. The goal of this study was to Effect of irrigation with conjunctive Caspian seawater and fresh water onyield and yield components of Parsley(Petroselinum crispum Mill) in greenhouse condition,the research was done based in completely randomized design including 3 replications as pot planting in Gorgan University of Agricultural Sciences and Natural Resources during 2015. The treatments included four levels (mixture of sea water tap water, alternate, half alternate and tap water), respectively. The results inducted that the effect of different irrigation regimes on root fresh and dry weight, root length, shoot length and shoot dry weight were highly significant (P
    Keywords: Exotic water, Half alternate, Mixture of sea water, Parsley, Saline, fresh water conjunction
  • Sheida Dehghan*, Nasrin Sayari, Bahram Bakhtiari Pages 947-959
    Drought is one of the great environmental disasters especially immense in arid and semi-arid. The drought indices as a tool for management practices and seeks to deal with the phenomenon of drought, are widely used in the world. One of these in dicators, is the Palmer Drought Severity Index (PDSI) that is used in many parts of the world to assess the drought situation and its continuation. In this paper, the drought state of Fars Province by using of this index over the period of 20 years (2014-1995) and according to meteorological data from six weather stations was assessed. The results showed that stations of Abade, Darab and Fasa in 2010 and 2001 for Eghlid and Lar and 1996 for Shiraz stations statistically were driest years in the period of 2014 to 1995. At this time changing in precipitation was also observed that in the years listed for droughts the steepest drop in rainfall was also remarkable. however in all stations in 2010 there were a sharp drop in rainfall that reflects the state of the drought this year.
    Keywords: Fars, Precipitation, Rooting, Soil moisture, weather station
  • J. Mehrabadi, B. Gahraman, K. Esmaili * Pages 960-971
    To stimulate the artificial self-burial of pipelines to provide safe conditions in erodible beds, the spoiler can be used at the top of the pipeline. The study of the performance of the spoiler that mounted on the naturally moveable pipe is a major gap that not founded in previous research. In this experimental study the parameters affecting the self-burial process of the pipelines were investigated. An equation was proposed for estimating the depth of self-burial in the normal settling of the pipe and was found that the moveable pipe decrease the scour depth by 54 percent in comparison with the fixed pipe. Maximum change in self –buried was obtained at S=D (S is the length of spoiler & D is the diameter of the pipe) that was equal to 70 and 67 percent of the diameter of the pipe in fine and coarse beds, respectively. The length of Lee-wake erosion in the pipe with natural motion was greater than in which the fixed pipe and increase with installed spoiler and spoiler height increases. Maximum length of Lee-wake erosion happened when S=D. The most burying is at zero degrees of the spoiler to the vertical axis.
    Keywords: Pipelines, Self –buried, Spoiler, transportation
  • H. Ahmadi*, S. Mard Ali, S. Behrouzi Niya Pages 972-987
    In this research the effect of soil modification with lime, on the behavior of concrete linings and acting forces has been numerically studied based on experimental data. Soil improvement has been conducted based on two different methods as removing upper problematic soil as well as local modification of soil around concrete linings with a given thickness. Modeling has been done using Plaxis finite element based model. Experimental uniaxial test data conducted on the original and modified soil samples has been employed to calibration of numerical model. Furthermore, acting forces on the canal linings, under three different operation conditions of canals were investigated. The results revealed that by modification and improvement of mechanical properties of base soil, the acting shear moments on the bed as well as side wall linings reduce, wherever, for mild slopes of side wall is more significant. Based on achieved results, at the horizontal removal method 55% and at the local modification case 20% reduction on the acting bending moment have been realized.
    Keywords: Bending moment, Lime stabilization, Local modification, Plaxis software
  • A. Abbaspour*, D.Farsadizadeh, M.R., Abdian Rokni Pages 988-998
    In this study, the characteristics of the hydraulic jump on semi cylindrical rough bed a diverging stilling basin has investigated experimentally. The experiments have done with the walls diverging angles of 0, 2, 4, 6 and 8 degree for six different Froude numbers. Total of 200 tests were performed within the range of 5 to 8 Froude numbers. The relative depth reduction of jump for the angles of 0, 2, 4, 6 and 8 degrees have obtained 10.5, 17.7, 22, 26 and 26.2 percent respectively. The average reduction of length jump for the angles of 0, 2, 4, 6 and 8 degrees with the rough bed have obtained 47.9, 57.4, 59.9 ,65.9, and 68.2 percent respectively and in the optimal case (C2.2D) the reduction of length jump is 75 percent. The divergence of a basin without roughness effect also has influenced on reducing the relative length of jump about 37 to 47 percent and the relative length of jump are directly related to the angle of a divergence basin.
    Keywords: Diverging stilling basin, Hydraulic jump, Length of jump, Semi-cylindrical Roughness, Sequent depth
  • Y. Beladi *, M. Shafai Bejestan Pages 999-1008
    One of the characteristics of the open channel in controlling of the pollutants are the dispersion coefficients. These coefficients are the main factor for diluting and increasing the exchange of pollutants with flow which in general reduces the mixing length. To increase the transverse coefficient and so reducing the mixing length many techniques have been applied and in this study the submerged vanes are used with variable numbers in flume widths.Tests are carried out at a glass wall rectangular channel with length 0f 15 m, 80 cm wide and 80 cm in Height in 5 different scenarios of without submerged vanes and with vanes in different number (3, 5, 7 and 9 vanes) and constant flow condition. The sodium chloride was injected in the channel center in constant discharge as tracer. The electric conductivity of the flow was measured by special instrument at four cross sections downstream of the vanes and the results are compared. The results show that generally the vanes are distribute the tracer across the section in a shorter length and the scenario with 7 vanes are more effective in which the transverse coefficient are 1.8 times with the case of no vanes.
    Keywords: Mixing length, Submerged vanes, Transverse mixing coefficient