List of Articles خاک‌های شور و سدیمی

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  1 - Using desalinization models for scheduling crop rotation of saline-sodic soils: a case study in Ramhormoz region, Iran
  safoora Asadi Kapourchal Mehdi Homaee
   Soil salinity is one of the important challenges for sustainable agriculture in arid and semi-arid regions. Accumulation of soluble salts within the soil profile adversely affects some physical and chemical properties of soils including osmotic pressure, permeabil More

   Soil salinity is one of the important challenges for sustainable agriculture in arid and semi-arid regions. Accumulation of soluble salts within the soil profile adversely affects some physical and chemical properties of soils including osmotic pressure, permeability and hydraulic conductivity. As a consequence, growth and development of plant is seriously reduced or fully ceased. The objective of this study was to assess using desalinization models for scheduling crop rotation of reclamation saline-sodic soils. Consequently, a large area of 45,000 ha with S4A3 (extreme salinity and sodicity) salinity/sodicity class was selected to obtain the required data ,in Khuzestan, Iran. This experiment was conducted with two treatments each with three replicates. In the first treatment, the experiment was conducted by applying just 100 cm water depth in four-25 cm intervals. In the second treatment, 10 Ton gypsum (78% purity rate) was applied prior to salt leaching together with leaching water. Soil samples were taken from 0-25, 25-50, 50-75, 75-100, 100-125 and 125-150 cm soil depths before, during and after each leaching water application interval. The required physical and chemical soil analyses were performed for the collected data. The results indicated that the logarithmic model can estimate the capital leaching requirement much better than other models. Based on the obtained model, the amount of net water needed to reduce initial soil salinity was calculated and finally crop rotation in two options was presented for reclamation of saline-sodic soils. The first option with preliminary leaching and cultivation of barley in continues leaching was assigned as the first priority. The second option with preliminary leaching and alfalfa cultivation and continues leaching was assigned as the next priority. The obtained results further indicated that the inclusion of scheduling crop rotation to the leaching practice, in addition to enhance effective leaching of soluble salts from the soil profile, causes considerable water saving. Manuscript profile
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  2 - A practical model for reclamation of saline and sodic soils
  Maryam Mohamadzadeh Mehdi Homaee Ebrahim Pazira
  Proper management of saline and sodic soils is essential for optimal conservation of soil and water resources. Accumulation of soluble salts within the root zone is one of the major problems in arid and semi-arid regions. To overcome this problem, leaching of accumulate More

  Proper management of saline and sodic soils is essential for optimal conservation of soil and water resources. Accumulation of soluble salts within the root zone is one of the major problems in arid and semi-arid regions. To overcome this problem, leaching of accumulated salts from such soils is necessary. The most important task in leaching practices is assessment of water quantity required for leaching of saline and saline-sodic soils. Therefore, reliable estimation of the required leaching water quantity is vital for reducing soil salinity to a desirable level. The objectives of this study were to introduce an empirical model to account for reclamation water and to compare the obtained results with some available models. Consequently, a large scale field experiment was conducted in jofeir region at south part of west Khuzestan plains, covering an area of 21285 ha with S3A2 salinity-sodicity classes. The intermittent pounding experiment was conducted with six double ring infiltrometers in a circular array. All experiments were accomplished by applying 100 cm of water in four-25 cm intervals. The leaching water was supplied from Karun rive. Four mathematical models were applied to the collected experimental data to derive a suitable empirical model. The results indicated that the proposed power model with maximum correlation coefficient of 0.83 and minimum standard error of 0.44 can provide reasonable estimates for leaching process compares to the previously proposed models. The results indicated that the empirical relations given by Rajabzadeh (2009), Hoffman (1980) and Laffelar and Sharma (1977) can not resemble the field conditions. However, the empirical relationships introduced by Pazira and Kawachi (1981) and Revee (1957) overestimate the depth of reclamation water. The empirical models of Pazira and Keshavarz (1989), Asadi et al., (2013) and Dieleman (1963) underestimated the depth of required reclamation water compares to the newly proposed model. Manuscript profile
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  3 - مقایسه آبشویی خاک‌های شور و سدیمی به دو روش غرقابی دایم و متناوب در اراضی جنوب استان خوزستان
  علی اکبر جلالی حسین سخایی راد
  در این پژوهش، آزمایش­های آبشویی به دو روش غرقابی دایم و متناوب، در کرت­های آزمایشی در اراضی جنوب استان خوزستان اجرا شد. به ازای کاربرد روش متناوب، مقادیریکسان آب آبشویی، نتایج بسیار بهتری در روند شوری­زدایی و سدیم­زدایی نسبت به روش دایم نشان داد. در روش More

  در این پژوهش، آزمایش­های آبشویی به دو روش غرقابی دایم و متناوب، در کرت­های آزمایشی در اراضی جنوب استان خوزستان اجرا شد. به ازای کاربرد روش متناوب، مقادیریکسان آب آبشویی، نتایج بسیار بهتری در روند شوری­زدایی و سدیم­زدایی نسبت به روش دایم نشان داد. در روش متناوب، به­کارگیری دوره­های تناوب 5 و 8 روزه، جهت آبشویی اراضی منطقه، در عمق یک متری خاک، تفاوت چندانی با هم نداشتند. اگر چه روند تغییرات شوری­زدایی و سدیم­زدایی در طی مراحل آبشویی و به خصوص در مراحل اولیه آن تفاوت کمی نشان داد، ولی در نهایت، اثر هر دو تناوب مشابه بود. مقایسه نتایج شوری­زدایی آزمون­های مزرعه­ای و مدل­های ارائه شده توسط سایر محققین نشان داد در بین مدل­های مورد بحث، تنها مدل دیلمان که یک رابطه نمایی و مبتنی بر روابط تجربی- نظری است، قادر بوده با دقت بهتری نسبت به سایر مدل­ها، نتایج حاصل از داده­های مزرعه­ای به هر دو روش آبشویی غرقابی دایم و متناوب را برآورد کند. این برآورد در روش متناوب، هم خوانی بیشتری با نتایج آزمون­های مزرعه­ای داشته است. هم چنین بررسی نتایج حاصل از ارقام سدیم­زدایی خاک­ها نشان داد، به دلیل وجود منابع کافی کلسیم موجود در خاک، بعد از شسته شدن خاک­های شور و سدیمی، با مشکل سدیمی شدن خاک­ها مواجه نبوده و نیازی به استفاده از مواد اصلاحی در خاک­های مورد آزمون نمی­باشد. Manuscript profile