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Water shortage problems have received wide attention since the past decades as the global environment and climate continue to change. To tackle with this escalating challenge, generations of study has been conducted in the research for water utilization efficiency. Reclaimed water has been widely used in many countries for industry, agriculture and landscape. Despite the economic value and environmental benefits the reclaimed water brings,. contents such as heavy metal ions, organic pollutants and pathogenic microorganisms may enter the soil-plant-atmosphere system, thus posing potential environmental health risks. Therefore, many laws, guidelines and standards have been published to maintain the security of irrigation with reclaimed water. This paper compares the standards of irrigation with reclaimed water among different organizations and countries by analyzing the similarities and differences from different types of classification and water quality parameters requirements, in which their advantages and limitations are demonstrated. Finally, some suggestions are provided for future development and modification of the relevant standards in this field. • Focuses on water quality and irrigation purposes of reclaimed water standards. • Refers to standards of some organizations and countries from different regions. • Summarizing uses and parameters from the standards into tables to compare. • Giving the recommended classification and parameters. [ABSTRACT FROM AUTHOR]

Available soil water in the root zone is an essential component of the water balance process since it greatly affects the crop water uptake and crop growth. In this study, a modified soil water deficit index (MSWDI) was established on the basis of the concept of readily available water (RAW), with the accumulated effect considered. This modified index was applied in six agro-meteorological stations in Songnen Plain of China to monitor the agricultural drought. The results showed that: 1) The MSWDI showed similar spatial and temporal agricultural drought patterns as its inherent indices, such as the soil water deficit (SWD), soil moisture deficit index (SMDI) and atmospheric water deficit (AWD), but exhibited a delay between atmospheric and soil water processes; 2) The MSWDI has a better correlation with the crop yield than its inherent indices. For example, its overall correlation coefficient is about 0.6 with the crop yields among six study stations and −0.7 for the number of droughts, while their corresponding values are 0.5 and −0.6, 0.5 and −0.6, and 0.3 and −0.4 for SMDI, SWD and AWD, respectively; 3) The MSWDI could also identify a slightly higher number of reported drought events during the 2000–2012 in comparison with SMDI, SWD and AWD, although it also over-predicts the number of drought events same as other indices. It mainly comes from the uncertainty of reported drought events. The proposed index can be used for agricultural drought monitoring and provides a useful tool for agricultural meteorology and water resource management. [ABSTRACT FROM AUTHOR]