滴灌带布置及滴头流量对土壤水氮分布和春小麦产量的影响

Effects of Different Drip-line Layouts and Dripper Discharges on Soil Water-nitrogen Distribution and Spring Wheat Yield

为了探究西北旱区春小麦适宜的滴灌带布置和滴头流量的组合,2016年3-7月在甘肃民勤县进行了春小麦大田试验,研究3种滴灌带布置方式(1管4行、1管5行、1管6行)和2种滴头流量(2. 2 L/h、3. 1 L/h)对土壤水氮分布规律、春小麦干物质量及产量的影响。试验结果表明:灌水后,滴头流量为3. 1 L/h的处理水分在水平方向运移比2. 2 L/h更大,而垂向运移更小;滴头流量相同时,滴灌带间距越大,两根滴灌带中间土壤含水率越小;施肥后,0~40 cm土层内土壤硝态氮含量随滴头流量增大而增大,而40~60 cm土层随滴头流量增大而减小;滴灌带间距增大,硝态氮易向滴头正下方40~60 cm土层内累积;滴头流量相同时,配置方式为1管6行的处理在春小麦干物质量及产量上要显著低于1管4行和1管5行的处理,而1管4行及1管5行无明显差异;配置方式相同时,滴头流量为3. 1 L/h处理的春小麦干物质量及产量均要高于2. 2 L/h的处理。综合考虑成本、产量等因素,建议选择滴头流量为3. 1 L/h、滴灌带布置方式为1管5行的组合。

In order to find out the suitable drip-line layouts and dripper discharges of spring wheat in northwest arid area,field experiments of wheat under drip irrigation had been conducted at a farm in Minqin county,Gansu province.Drip irrigation experiments had set up two kinds of dripper discharges(2.2 L/h and 3.1 L/h)and three kinds of drip-line layouts(one drip-line for 4,5 and 6 rows of wheat,respectively).By analyzing soil water-nitrogen distribution,spring wheat water consumption,physiological indicators and yield of different irrigation parameters,the results showed that:horizontal water transport of 3.1 L/h dripper discharge in soil was larger than that of 2.2 L/h,while the vertical water transport was smaller with the same irrigation amount in the loam with the same irrigation amount;when the dripper discharge was the same,the soil water content at 1/2 drip-line spacing decreased with the drip-line spacing increased.After fertilization,the accumulation of nitrate nitrogen in 0-40 cm soil layer was increased with the dripper discharge increased,while that in 40-60 cm soil layer showed different tendency with the dripper discharge increased.Accumulation of nitrate nitrogen beneath dripper increased with the drip-line spacing increased.With the same dripper discharge,total dry mass and yield of the treatment of one drip-line for 6 rows of wheat were significantly lower than that of the treatment of one drip-line for 4 and 5 rows of wheat,but there was no significant difference between treatment of one drip-line for 4 and 5 rows of wheat.With the same drip-line layouts,compared with 2.2 L/h dripper discharge treatment,the 3.1 L/h dripper discharge has the higher total dry mass and yield.Considering the yield,cost and other factors,it was recommended to choose the drip layout figuration that one drip-line for 5 rows of wheat with 3.1 L/h dripper discharge.