نوع مقاله : مقاله کامل علمی پژوهشی
نویسندگان
1 گروه آبیاری و زهکشی پردیس ابوریحان، دانشگاه تهران
2 گروه آبیاری و زهکشی، پردیس ابوریحان، دانشگاه تهران
3 دانشگاه تهران- پردیس ابوریجان- گروه آبیاری و زهکشی
4 گروه ابیاری و زهکشی - پردیس ابوریحان- دانشگاه تهران
5 پردیس کشاورزی دانشگاه تهران کرج
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
Background and Objectives: Due to the population increase and growing need for food production development in cities and to improve urban agriculture through urban greenhouses, there is an urgent requirement to provide optimal subsurface irrigation methods. Optimal irrigation methods mean methods that reduce water consumption and allow the use of lower quality water for irrigation while maintaining product quality. There are different methods for subsurface irrigation in greenhouses, for example there are some hydroponic methods which need special equipment and many studies have been conducted on them. In this research, performance of a new sub-irrigated planter method (SIP) for panting basil plant in two seasons in a greenhouse, in term of water productivity was evaluated and compared with conventional surface irrigation.
Materials and Methods: In SIP system, plant was planted in pot and a water reservoir (saturated gravel reservoir) was prepaid below the growing medium in pot (bottom of pot) to provide the water for plants through capillary action in growing medium (upper part of pot). Variable parameters to study were: depth of growing medium (D1: 50 cm and D2: 30 cm), Type of growing medium: (clay loam + cocopeat + perlit (SC) and cocopeat + perlit (C)) and three irrigation salinity levels (1.2, 3.5 and 5 dS.m-1: basil tolerance to irrigation water salinity: 1.5 dS.m-1); which were compared in both SIP and surface systems.
Results: All SIP-C treatments had considerably higher water productivity in 5% statistical level compared to surface treatments which proved the superiority of C growing medium to be used in SIP systems in order to increase water productivity in a greenhouse. Considering optimum depth, water productivity in SIP-SC-D1 was not meaningfully higher than SIP-SC-D2; although in SIP-C, all D2 treatments had considerably higher water productivities than D1s. As a result it is recommended to use lower depth of growing medium while using C growing medium in SIP systems. Increasing irrigation water salinity level did not affect the fresh yield weight in SIP systems; although the salinity level was remarkably high in surface layers of SIP pots unlike the higher salinity layers observed at bottom of surface pots; which shows the need to monitor the growing medium salinity levels during growing season and applying the leaching between growing seasons when necessary in SIP systems.
Conclusion: This study showed that sub-irrigated planter method while is a very simple method and has no need to complex technology and expensive equipment and installation, significantly reduces the amount of water required for irrigation and also is able to compete with conventional surface irrigation systems. Therefore this method can be used as conservative system to save both water and soil as an agricultural goal and keep the productivity in high levels.
کلیدواژه‌ها [English]
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