تاثیر آبیاری زیرزمینی با پساب شهری تصفیه شده بر عملکرد گیاه برنج

با توجه به محدودیت منابع آب در کشور، استفاده از شیوه های نوین آبیاری برنج با مصرف کمتر آب امری بدیهی خواهد بود. یکی از راه های افزایش بهره وری آب، استفاده از روش آبیاری زیرزمینی است. همچنین برای مقابله با بحران آب می توان از آب های نامتعارف و به عبارت دیگر آب های با کیفیت نامطلوب استفاده نمود. به منظور بهبود کیفیت آب مصرفی در کشاورزی روش های مختلفی وجود دارد که یکی از آن ها استفاده از میدان های مغناطیسی است. در پژوهش حاضر اثر مغناطیسی‌شدن پساب تصفیه خانه شهری گرگان و آب معمولی به روش آبیاری زیرزمینی در پردیس کشاورزی دانشگاه علوم کشاورزی و منابع طبیعی گرگان بر صفاتی همچون عملکرد شلتوک، عملکرد بیولوژیک، شاخص برداشت، کارایی مصرف آب، بهره وری فیزیکی آب و بهره وری اقتصادی آب مورد بررسی قرار گرفت. آزمایش به صورت فاکتوریل در قالب طرح بلوک های کامل تصادفی در 3 بلوک، از اردیبهشت تا شهریور ماه سال 1397 انجام شد. تیمارهای آزمایش شامل فاکتور نوع آب آبیاری در دو سطح شامل آب معمولی (c) و پساب تصفیه شده شهری گرگان (w) و فاکتور دوم شامل روش اصلاح آب در دو سطح شامل مغناطیس (m) و عدم مغناطیس (o) بود. نتایج مقایسه میانگین فاکتور نوع آب نشان داد که بین تیمار پساب و آب معمولی در پارامترهای اندازه گیری تفاوت معنی داری مشاهده نشد. فاکتور روش اصلاح آب نشان داد که تیمار غیرمغناطیس در پارامترهای عملکرد شلتوک، کارایی مصرف آب، بهره وری فیزیکی آب و بهره وری اقتصادی آب نسبت به تیمار مغناطیس معنی دار بود اما در پارامترهای عملکرد بیولوژیک و شاخص برداشت اثر معنی دار مشاهده نشد. همچنین مقایسه میانگین اثرات متقابل نوع آب و روش اصلاح بر همه پارامترهای اندازه گیری شده حاکی از برتری پساب غیرمغناطیس نسبت به بقیه تیمارها درسطح 5 درصد بود. براساس نتایج این تحقیق می توان گفت که کشت برنج از نظر آبیاری نیازی به ایجاد یک لایه ایستابی در سطح خاک ندارد و همچنین استفاده از پساب تصفیه خانه شهری گرگان به عنوان آب آبیاری، علاوه بر امکان کاهش برداشت از منابع آبی با کیفیت بالا، هزینه های مصرف کود (شیمیایی و آلی) در تولید محصول را نیز کاهش داد.

The Effect of Sub-irrigation on Rice Yield with Refined Municipal Wastewater

Introduction: Due to limited water resources in the country, the use of new methods of irrigation with low water consumption seems necessary. Subsurface irrigation is one of the few methods to increase crop water productivity. Also, in order to cope with the water crisis, unconventional water can be used, in other words, poor water quality is being applied. There are several methods for improving the quality of water in the agriculture section, one of which is the use of magnetic fields. The purpose of this study was to investigate the effect of groundwater table management on reducing water consumption and to investigate the possibility of subirrigation (drainage controlled) with magnetized wastewater of Gorgan urban refinery on rice yield.;Materials and Methods: This study was conducted from May to September of 2018 in Gorgan Agricultural and Natural Resources University. The experiments were carried out in a lysimeter with a diameter of 30cm and a height of 50cm. The experiment was conducted as a factorial based on randomized complete block design with three replications. Treatments included water type factor (ordinary water (C) and sewage (W)) and water correction factor (magnetic (M) and nonmagnetic (O)). To control the water level, two water tanks were used, one as a stabilizer water table and another to measure the amount of water used. Part of the ordinary water and wastewater was magnetized using a DC magnetic field generator with magnetic one tesla field intensity. Underground irrigation was then carried out on the soil columns in which the rice plant was cultivated so that the water table depth was fixed at 5 cm from the soil surface. The lysimeters were irrigated with ordinary water for one week, in the second week of treatments were applied. At the end of the growing season, traits such as rice husk yield, biological yield, harvest index, water use efficiency, physical water productivity and economic water productivity were determined. The measured data were analyzed using SPSS. Also, comparisons of means were performed by using the ttest and Duncan tests at 5% level of probability.;Results and Discussion: The results of the comparison mean water type factor showed that there was no significant difference between the wastewater and the normal water in the parameters of the measurements. Correction Water showed that nonmagnetic water was significant in rough rice yield, water use efficiency, water physical productivity, and water economic efficiency compared to magnetite, but on biological yield and harvest index had not a meaningful effect. Also, the comparison of the mean of water type and correction water method on all measured parameters indicated that the nonmagnetic wastewater was superior to the rest of the treatments at the 5% level.;Conclusion: This study was conducted to investigate and further study two methods of controlled drainage management and underground irrigation for rice cultivation with the Gorgan municipal wastewater treatment plant. Based on the results of the comparison of mean interaction effects of treatment compounds, nonmagnetic effluent was identified as the best treatment composition in this experiment. According to the results of this research, we can say: Rice cultivation in terms of irrigation does not require the formation of a standing water layer on the surface of the soil. Also, by using wastewater of Gorgan urban refinery for irrigation water, in addition to reducing the harvesting of highquality water resources, the cost of fertilizer use (chemical and organic) in the production of crops can be reduced. Overall, the results of this study showed that the magnetic factor had no effect on the improvement of rough rice yield, water use efficiency, physical productivity water and economic efficiency of water under underground irrigation conditions. However, it should be noted that the results of this research are only It is obtained by a magnetic device model. Therefore, it is possible that the use of different models of magnetic devices results in different results. It is also probable that the passage of irrigation water with different compositions (percentage of cations and various anions) from the magnetometer can lead to different results on other crops or cultivars of a crop.