斜发沸石对干湿交替灌溉驱动下稻田氨挥发和氮素淋失的影响机理研究

我国是水稻生产大国，水稻生产耗水约占我国农业年耗水量的一半。水稻田化肥的大量施用也是造成水、土资源污染的主要成因之一。为减少稻田用水量和化肥施用量，本研究拟在辽宁中部地区和滨海地区两个灌溉试验站，采用干湿交替灌溉技术,在掌握稻田持续淹灌条件下氮循环特征的基础上，重点研究斜发沸石对水稻氮吸收和稻田氮素损失的影响，探索斜发沸石降低氨挥发和减少氮素淋失的响应机理。通过研究干湿交替灌溉驱动下稻田土壤氧化还原电位、田间持水能力、土壤矿化氮以及氮素流失等特征，阐明在干湿交替灌溉驱动下斜发沸石（不同用量和粒径）降低氮素流失的机制和节水节肥潜力；观察不同斜发沸石施用周期下氨挥发和氮素淋失的差异，摸清斜发沸石的长效性机制，为减少水稻生产用水和氮肥用量并保障水稻生产的可持续性提供理论基础和技术支撑。

As a big rice production country, China’s water consumption of rice production accounts for about half of the total water consumption. Excessive fertilizer in paddy field is one of the main causes being responsible for a series of pollution problems of water and soil resources. This study is intended to be conducted at two sites located in central Liaoning and coastal areas, respectively. Clinoptilolite zeolite (CZ) effects of rice crop nitrogen uptake and nitrogen loss under alternate wetting and drying irrigation (AWD) are emphatically evaluated in order to reveal influence mechanism of reduced ammonia volatilization and N leaching by CZ application under AWD after primary understanding of the characteristics of the nitrogen cycle under continuous flood irrigation in paddy field. Oxidation reduction potential, field moisture capacity of water, soil nitrogen mineralization and nitrogen loss characteristics under AWD are mainly observed under different CZ treatments (different dosage and particle size) to elucidate the incentives mechanisms for reducing N loss and the potential of water and fertilizer saving. In addition, ammonia volatilization and N leaching under different CZ cycles are analyzed to clarify the after-effect and long-term effects of CZ. It concludes that it is of importance to conduct this study to provide theoretical basis and technical support for reducing water and nitrogen fertilizer as well as ensuring the sustainability of water and nitrogen fertilizer.