بازچرخانی زهاب مزارع نیشکر برای کشت برنج با هدف بهبود بهره وری آب در شبکه های آبیاری و زهکشی

نوع مقاله: مقاله پژوهشی

نویسندگان

1 بخش فنی و مهندسی مرکز تحقیقات اهواز

2 استادیار پژوهشی بخش تحقیقات اصلاح و تهیه نهال و بذر، مرکز تحقیقات کشاورزی و منابع طبیعی استان خوزستان، سازمان تحقیقات، آموزش و ترویج‌کشاور

3 استادیار پژوهشی، موسسه تحقیقات برنج کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی

4 مدیر مطالعات کاربردی کشت و صنعت نیشکر میرزا کوچک خان

5 کارشناس دفتر توسعه و ترویج روشهای نوین آبیاری و زهکشی سازمان آب و برق استان خوزستان

چکیده

تولید زهاب درجنوب استان خوزستان یکی از مشکلات جدی است. استفاده از این زهاب بر میزان تخصیص آب به شبکه های آبیاری استان اثرگذاراست. بازچرخانی زهاب برای‌کشت برنج می‌تواند به عنوان بستری مناسب در منطقه موردتوجه قرار گیرد. برای نیل به این هدف، پژوهشی به‌صورت‌کرت‌های یک بار خرد شده درقالب طرح بلوک‌های‌کامل تصادفی با دو عامل و سه‌تکرار درکشت وصنعت میرزا کوچک خان اجرا شد. دورآبیاری با زهاب نیشکر شامل هر روزه(I0) و تناوب‌‌های یک روز در میان(I1) و دو روزدرمیان(I2 )به عنوان عامل اصلی در نظرگرفته و9رقم ولاین اصلاحی برنج مقاوم به شوری درکرت‌های فرعی قرارداده‌شدند. نتایج تحقیق نشان داد با کاهش قابل توجه آب از دورآبیاری هر روزه به تناوب‌های یک روز در میان و دو روز در میان، میزان عملکرد ازI0 با متوسط2140به 2248کیلوگرم بر هکتار به I1 روندی افزایشی‌دارد و ‌در I2 نسبت به I0‌با افتی30درصد به شدت رو به رو می‌شود. در پایش درصد سدیم قابل تبادل خاک(ESP)، نتایج بررسی‌ها نشان داد که درهردو رژیم آبیاری I0وI1، خاک مزرعه در وضعیت سدیمی بودن قرار نمی‌گیرد و تنها در وضعیت شور باقی می‌ماند. این مسئله به‌دلیل آبیاری در سراسر فصل رشد و وجود زهکشی زیرزمینی است که باعث خروج املاح از پروفیل خاک شده است. هرچند درI2، به‌دلیل خشکی‌دادن مزرعه و هجوم شوری به لایه‌های سطحی خاک، وضعیت پروفیل خاک تا زیر عمق توسعه ریشه با افزایش 17درصددر ESPبه وضعیت سدیمی نزدیک می‌شود. معلوم شد در این مدت، شوری عصارۀ اشباع خاک 100 درصد افزایش یافته‌است.

کلیدواژه‌ها


عنوان مقاله [English]

Drainage water recycling of sugarcane farms in Khuzestan for rice cultivation with the aim of improving water productivity in irrigation and drainage networks

نویسندگان [English]

  • Abdolali Gilani 2
  • Ali Akbar Ebadi 3
  • Mohammad Ali Shayan 4
  • khadijeh Sanei Dehkordi 5
2 1. Research Assistant Professor of Seed and Plant Improvement Research Department, Khuzestan Agricultural and Natural Resources Research and Education Center, Agricultural Research Education and Extension Organization (AREEO), Ahwaz, Iran.
3 3. Assistant Professor at Rice Research Institute of Iran (RRII), Agricultural Research Education and Extension Organization (AREEO)
4 4. Manager of Research department, Mirza Kochak Khan Sugarcane Agro Industry Company
5 5. Expert of New Irrigation and Drainage Methods Development and Extension Office, KWPA
چکیده [English]

Introduction
In Khuzestan province, waste water release from various sources, especially agriculture, is a serious problem. The drainage water volume of the irrigation and drainage networks of the Karun river basin is about two billion cubic meters per year, considering sugarcane agro-industries and fish farming as the main sources of drainage water. Time-Averaged salinity of this drainage water, with source of sugarcane agro-industries, is about 6 dS/m which is valuable to cultivation of salt-tolerant crops or aquaculture with saline water as part of the solutions for drainage water management and providing sustainable environment. This can also affect the amount of water allocated to irrigation networks and sugar cane industries. In this regard, reusing of agricultural drainage water to produce rice salinity resistant varieties and lines as a high-yielding strategy in Khuzestan, especially in the central and southern areas with high water demand, can be very useful.
Methodology
This study was conducted at farm code L08-20, in Mirza Koochak-Khan agro-industry Company, using split plot in a randomized complete block design with two factors and three replications. Irrigation interval with saline water daily, one and two day alternations were main factor and 3 salinity-tolerant rice lines were sub factors. Subsequent selections from the International Treasury of rice cultivars, 4 salinity-tolerant breeding lines, one international control line and local cultivar were subplots. The amount of water applied to the plots was measured throughout the growing season and samples for determination of physical and chemical properties of soil and drainage water before planting until harvesting time for soil monitoring and soil salt balance analysis were collected. In this study, grain yield, biomass and harvest index were determined. Finally, water productivity was estimated as yield per cubic meter of water.
Results and Discussion
Due to the average salinity of irrigation water, 6 dS/m, the volume of water consumed during the growing season was estimated to be 30,000 m3/ha, based on water requirement calculations. Based on irrigation management, applied volume of water was estimated about 37500 m3/ha for treatment I0, 19500 m3/ha for treatment I1 and 13200 m3/ha for treatment I3. The average salinity of soil saturated extract was measured about 4 dS/m before cultivation. Except for the first 15 days, when irrigation was carried out with full irrigation for transplanting stage, the trend of soil salinity changes was decreasing, during the rest of the growing season until harvesting. Salinity of soil increased in all three irrigation managements. The rate of salinity changes varied from 50% in the daily irrigation round to 100% in the two-day irrigation round compared to pre-cultivation soil salinity. During the crop growth from the transplanting, daily, one and two day rounds irrigation managements causes enterance of 190, 99 and 66 tonnes of salt in the top 100 cm of soil profile. Increased salinity over growing time for daily, one and two days irrigation treatments, were 6, 6.5 and 7.2 dS/m, respectively, according to soil salinity, 4 dS/m, before planting. Considering the the soil with 51% porosity, it can be concluded that 7.6, 9 and 11 tonnes of salts stored in the upper 60 cm of soil profile for daily, one and two days irrigation management and the rest of the solutes extracted from soil profiles through underground drainage system. This behavior illustrates the importance of drainage, especially underground drainage system, in agricultural drainage reclamation and saline operations for soil conservation. The results showed significant decrease of farm applied water in daily irrigation water management relative to two and three-day intervals. Farm yield increased 6% from I0 with an average of 2139.3 to 2248 kg, I1 and then decreased by 30% in the three-day irrigation period.
Conclusions
The results showed that the highest and lowest water productivity resulted from I2 and I0 irrigation treatments, respectively, with values of 0.128 and 0.057kg/m3. ESP monitoring showed that at the end of the growing season soil profile was not sodic and remained in saline condition for two irrigation regimes I0 and I1. However, in the I2 irrigation regime, the soil profile status approached to the sodium state, with 17% increasing in ESP and 100% increasing in salinity relative to planting time. This behavoir is because of field drying between two irrigation events which causes salinity invasion to soil surface layers, so it can be addressed by considering the percentage of leaching at the end of the growing season.
Acknowledgement
The authors consider it necessary to thank Mirza Koochak-Khan agro-industry Company, Khuzestan Water and Power Authority (KWPA), Agricultural Engineering Research Institute )AERI), Rice Research Institute of Iran )RRII), Khuzestan Agricultural and Natural Resources Research and Education Center to the support of the present study.

کلیدواژه‌ها [English]

  • Drainage system
  • saline resistant lines
  • soil monitoring
  • Intermittent irrigation

مقالات آماده انتشار، پذیرفته شده
انتشار آنلاین از تاریخ 09 اسفند 1398
  • تاریخ دریافت: 12 آذر 1398
  • تاریخ بازنگری: 06 اسفند 1398
  • تاریخ پذیرش: 09 اسفند 1398