Main content area

Zeolite amendment coupled with alternate wetting and drying to reduce nitrogen loss and enhance rice production

Sun, Yidi, Xia, Guimin, He, Zhenli, Wu, Qi, Zheng, Junlin, Li, Yinghao, Wang, Yanzhi, Chen, Taotao, Chi, Daocai
Field crops research 2019 v.235 pp. 95-103
ammonia, ammonium nitrogen, drying, experimental design, field experimentation, financial economics, grain yield, irrigation management, leaching, lysimeters, nitrate nitrogen, nitrogen, production technology, rice, soil conditioners, soil depth, volatilization, zeolites
Clinoptilolite zeolite (Z) has been increasingly recognized as a valuable soil conditioner, which is beneficial to nitrogen (N) loss reduction and crop yield improvement. However, limited information is available for a rice production system, especially under alternate wetting and drying irrigation (AWD). Therefore, a 2-year field experiment with lysimeter was carried out in a split plot design with two irrigation regimes (CF: continuously flooded irrigation, AWD: alternate wetting and drying irrigation) as main plots and three Z amendment rates (0, 5 and 10 t Z ha−1) as sub-plots. The impact of Z amendment on ammonia (NH3) volatilization, N leaching, rice grain yield, water productivity (WP) and economic benefit were analyzed under both irrigation regimes. The results showed that AWD slightly reduced NH3 volatilization without Z application, but significantly increased residual mineral N (RMN) in soil at the depths of 0 − 30 and 30 − 60 cm, and NH4+-N and NO3−-N leaching, relative to CF. AWD-grown rice significantly improved WP without affecting grain yield in 2016, but reduced yield in 2017 without Z amendment. Compared with control (without Z amendment), addition of 5 and 10 t Z ha-1 increased RMN by 12 and 21%, respectively in the 0 − 30 cm soil depth, but reduced it by 18 and 32%, respectively in the 30 − 60 cm soil depth. Total NH3 volatilization and NH4+-N and NO3−-N leaching loss decreased with increasing rates of Z amendment. Z amendment significantly increased N uptake, rice grain yield, economic benefit and WP, especially under AWD. In the two years, integration of 10 t Z ha-1 with either AWD or CF management reduced NH3 volatilization without increasing N leaching and increased rice grain yield and WP, with an increased economic benefit of $126 − 195 ha-1, as compared to conventional management (CF without Z). The use of zeolite merits further investigation for application in the rice production systems.