ABSTRACT
Around the world, there is increasing pressure on agriculture, horticulture, and landscape greening to replace good quality water with ‘unconventional water’ of lower qualities such as brackish, drainage, and/or treated wastewaters, especially in (semi)arid areas. The area of irrigated land using more or less treated sewage waters is estimated to be at least 3.5 million ha, China not included (Hamdy 1995; Qadir et al. 2010). Annual economic loss caused by soil salinity is estimated to be some 12 billion US$ globally (FAO 2018). It is estimated that about 10 million ha of irrigated land is abandoned yearly, due to adverse effects of irrigation management, mainly from secondary salinization (Pessarakli and Szabolcs 2011).
