The problem of water shortage is one of the major limiting factors in food production and agriculture development in the arid and semi arid regions. Reclaimed water is one of the most significant available water resources that shall be consumed in agriculture and urban landscape maintenance. In order to investigate the impact of water quality and its application method on olive trees this experiment was carried out during 2010-2012 in the semiarid central part of Iran on young olive trees. The trees were irrigated by a new subsurface-leaky irrigation (SLI) system and surface irrigation in line with irrigation with recycle and clean water for 24 months. The results revealed that SLI system could enhance trees growth, leaf area, Fv/Fm and photosynthesis by68, 26, 4 and 42% respectively, although it decreased leaves soluble sugars (47%). In addition, irrigating trees by SLI system using reclaimed water could increase N and Mg uptake 138 and 8% respectively. Plants irrigated with RW showed improved growth (42%) leaf area26% and photosynthesis 23.4% compared with CL water. Furthermore Mg, Na, K, P and N surprisingly increase 12, 59, 30, 7, and 92 % respectively in leaf tissue in application recycle water. In overall, this experiment showed that recycled water could be a favorable resource for olive trees irrigation and SLI irrigation system was more efficient in irrigation in this research.
Key word: Recycle water, subsurface irrigation, Nutrition element
Abbreviation: CW: clean water, RW: recycle water, SI: surface irrigation system, SLI: subsurface leakage irrigation, Ph: photosynthesis, E: evaporation, gs: stomata conductance,
Water shortage in arid and semi-arid regions and declining its availability to a crisis level throughout the world command that continued and increased agricultural production will depend on utilization another water sources for irrigation. (Bernstein Nirit et al, 2006). Municipal wastewater is an important alternative source of water for irrigation, which will increase as the population grows and the demand on freshwater increases. (Ali M. Hassanli et al 2008).
Using wastewater in irrigation has been widely practiced in many countries specially those who are located in arid and semi-arid regions. Increasing wastewater by the growth urban society in Iran that located in dry region can be considered for optimum use of wastewater for dominant the water limitation problem. As well as, urban wastewater can be used not only for water source also it will be used as a nutritional element for plants, and is an enormous nutrient source and organic matter, too (Ratton et al., 2005, Meli et al., 2002, Hamid I. Tak et al, 2013). Inasmuch the water shortage is a limiting factor for increased agricultural production and green space development, therefore wastewater application may be suitable.
When water supplies are restricted, improving irrigation methods is important to meet the higher water demand. Malash et al,...