斜发沸石对辽西半干旱区节水灌溉稻田的节水减肥效应

Water-saving and Fertilizer-reducing Effect of Clinoptilolite in Water-saving Irrigated Paddy Fields in Semiarid Areas of Western Liaoning

针对辽西半干旱区稻田土壤保水保肥能力低下的问题,并为探明节水灌溉稻田中斜发沸石的节水减肥效应、明确其调控的氮积累过程参数与水稻产量之间的关系,于2019年和2020年在辽西彰武县绿维农场进行了大田试验。采用随机区组试验设计,设置常规淹灌(对照)、干湿交替灌溉和施加斜发沸石、干湿交替灌溉和施加斜发沸石并减氮1/4、干湿交替灌溉和施加斜发沸石并减磷1/4、干湿交替灌溉和施加斜发沸石并使用等量有机肥替代传统速效肥等5个处理,对水稻耗水量、干物质量、吸氮量等指标进行监测。结果表明,相较于常规淹灌,节水灌溉条件下施用斜发沸石可以显著节水4.8%~11.4%、提高水分生产率6.2%~15.5%、减少磷肥用量25%,最高增产9.7%;水稻耗水量呈现先增加、后降低的单峰曲线规律,而水稻需氮规律符合Richards生长函数变化趋势;主成分分析表明,水稻高产的3个关键因素为前期氮素积累量、氮素积累时间和积累过程的平稳性;干湿交替灌溉和施加斜发沸石并减磷1/4处理与干湿交替灌溉和施加斜发沸石处理增产的原因主要是提高了叶片的氮素积累,继而提高了干物质积累量和氮素在穗部的积累量。综上,干湿交替灌溉和施加斜发沸石并减磷1/4处理与干湿交替灌溉和施加斜发沸石处理氮素积累总量和氮素积累时效均较高,且氮素积累较平稳,是辽西半干旱地区稻田节水增效的重要模式。

The low water and fertility retention capacity of paddy soils in the semiarid area of Western Liaoning is one of the important obstacles restricting water conservation and high yield in this area.In order to study the water-saving and fertilizer-reducing effects of clinoptilolite in water-saving irrigated paddy fields and clarify the relationship between the process parameters of nitrogen accumulation and rice yields,field experiments were conducted in semiarid areas of Western Liaoning in 2019 and 2020.Conventional flooding irrigation treatment was taken as control,and alternate wet-dry irrigation with application of clinoptilolite,alternate wet-dry irrigation with application of clinoptilolite and 1/4 less nitrogen treatment,alternate wet-dry irrigation with application of clinoptilolite and 1/4 less phosphorus treatment,alternate wet-dry irrigation with application of clinoptilolite and local organic fertilizer instead of quick-acting fertilizer treatment,were designed to monitor rice water consumption,dry matter,nitrogen uptake,etc.Results showed that compared with conventional flooding irrigation,clinoptilolite coupled with alternate wet-dry irrigation significantly saved irrigation water by 4.8%to 11.4%,increased water productivity by 6.2%to 15.5%,reduced phosphate fertilizer by 25%,and increased rice grain yield up to 9.7%.The rice water consumption presented that it was firstly increased and then decreased,and the plant nitrogen requirement conformed to the Richards's growth function.The principal component analysis showed that the three important parameters affecting the highrice yield were the nitrogen accumulation amount,nitrogen accumulation duration and stablity of nitrogen accumulation process.The significant increase in rice yield for“alternate wet-dry irrigation with application of clinoptilolite and 1/4 less phosphorus”treatment,and“alternate wet-dry irrigation with application of clinoptilolite”treatment was due to the increased nitrogen accumulation in leaves,and then increased the dry matter accumulation and the nitrogen accumulation in rice panicles.In summary,alternate wet-dry irrigation with application of clinoptilolite and 1/4 less phosphorus treatment,and alternate wet-dry irrigation with application of clinoptilolite treatment had characters of both high nitrogen accumulation amount and duration,and stable nitrogen accumulation process,which became the important ways to save irrigation water and increase production efficiency in apaddy field of the semi-arid area of Western Liaoning.