specific limitations should be addressed regarding treated water quality: the necessity for nutrients is according to their availability in the soil and they are in general applied through fertilizers ormanure. However, as previously described, the potential for nutrient leaching has to be taken into account to avoid exploitation of nearby water bodies. The Australian national water quality management strategy utilizes long-term (100 years) (LTV) and short-term (20 years) values (STV) in order to control nutrient concentration: STV concentration has to be sufficient to maintain no decrease in crop yield or quality, and LTV has to be low enough to minimize contamination of surrounding
water resources (Table 4) [14]. In general, FAO's standards for nutrient concentration meet the LTV requirements (Table 4) [9]. FAO also indicates the maximum concentration of trace elements in irrigation water (Table 5) [9,14]. These, when present, can cause health risks by transfer and accumulation from water, via plants, to humans.