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In the soil column experiments, the irrigation amount varied from 4.8 to 12 L, and the nitrogen application rate was from 80 to 360 kg ha−1. Three fertigation strategies were tested. The results indicated that an increase in water input led to an increase in the area of pH decrease in the soil at 10 days after the irrigation ended for a given lateral depth of 10 cm. The measurement of nitrogen distribution showed that the nitrogen content in the soil was significantly increased with the nitrogen application rate. Fertigation strategies substantially affect the pH and nitrogen distributions in soil. The strategy of applying water at first for one-fourth of the total irrigation time (1/4W), then applying fertilizer solution for one-half of the total irrigation time (1/2N), followed by applying water for the remaining one-fourth of the total irrigation time (1/4W) made a minimal soil pH decreasing area and a homogeneous nitrate distribution at 0–20 cm depth. Therefore, to reduce NO3-N leaching and avoid deep soil acidification, a dripline depth of 10 cm with an irrigation amount of 4.8 L and a nitrogen application rate of 80 kg ha−1 through the 1/4W–1/2N–1/4W fertigation may be suggested. HIGHLIGHTS Minor water and nitrogen input with shallow lateral depth can be conducive to reduce nitrate leaching.; The NO3-N accumulation and pH decrease mainly appeared in surface soil through 1/4W–1/2N–1/4W fertigation.; Drip irrigation is feasible to mitigate soil acidification.; An ongoing field experiment confirms and improves the results of laboratory experiments without crops.;

To quantitatively evaluate the effect of RW irrigation on yield, WUE, and IWUE, and identify aqueous, edaphic, and management factors that favor improved yield, WUE, and IWUE compared to control practices, a meta-analysis was conducted. The results indicated that RW irrigation is beneficial for improving crop yields, WUE, and IWUE (16.8, 23.8, and 18.7%, respectively). However, its effectiveness is highly dependent on the aqueous, edaphic, and management factors of the studies evaluated. Greater responses were found in practices using RW with a pH < 7 or a nitrogen content

Due to the severe shortage of water resources, more than 33.3% of treated sewage effluent (TSE) is used for agricultural irrigation in China. There are significant advantages of using drip irrigation of TSE. However, it is still not known how TSE drip irrigation influences the soil environment. It is known that drip irrigation technical parameters determine the distribution of TSE in soil and have a substantive effect on the soil environment, while the magnitude of these impacts depends on the TSE quality. Since the application of conventional water resources is limited, TSE is expected to be used more frequently for agricultural irrigation. The growing concern of soil environmental risk due to TSE drip irrigation requires further study of the interaction and coupling of drip irrigation and TSE. This summary will help understand TSE drip irrigation in China, and guide the practice of reclaimed water utilization in the future. HIGHLIGHTS Reclaimed water irrigation agriculture has wide possibilities in China.; The effects of drip irrigation on soil and crop are highly dependent on irrigation parameters and materials contained in reclaimed water.; The effects of reclaimed water drip irrigation on soil and crop need continuous monitoring and evaluation.; Reclaimed water could promote agriculture and water sustainability when based on risk control.;