滴灌带埋深对田间土壤水氮分布及春玉米产量的影响

地下滴灌是在滴灌技术日益完善的基础上发展而成的一种新型高效节水灌溉技术。本文以春玉米为研究对象，在一种砂壤土上使用压差式施肥罐和比例施肥泵两种施肥装置，研究了3种滴灌带埋深（0cm，15cm，30cm）对田间土壤水氮分布及作物生长的影响。田间春玉米滴灌小区试验的结果表明：滴灌带埋深影响田间土壤垂直剖面中水氮的分布状态；在本试验条件下，经过多次滴灌后，0cm埋深处理的地表滴灌其土壤剖面下部70cm以下土层的土壤含水量和NO3^-N含量均高于15cm和30cm埋深处理的地下滴灌；15cm和30cm埋深处理的地下滴灌其春玉米籽粒和鲜穗产量均显著高于0cm埋深处理的地表滴灌，以T区为例，15cm和30cm埋深处理的籽粒产量比0cm埋深处理的地表滴灌分别提高10．1％和11．6％，鲜穗产量分别提高5．6％和6．6％。

Effects of drip irrigation placement depth on distribution of soil water & nitrogen and spring maize yield

Based on the development of drip irrigation, Subsurface Drip Irrigat ion ( SDI) is a new type of high-efficient water saving irrigation technique. An experiment on SDI for spring maize was conducted in two plots of sand soil f ield with three placement depths of 0cm, 15cm and 30cm below the soil surface. Two fertilizing devices used for the two plots were pressure-type fertilizer tank and piston fertilizer pump. This paper discussed the effect of placement depth of drip-tape on distribution of soil water & nitrogen and spring maize yields. The study indicated that placement depths of drip-tape affect the distribution of soil water& nitrogen in vertical profiles of soil. After several runs of drip irrigation, the soil water and NO-3- N content of soil layer at 70cm below the soil surface in case of irrigation with 0cm placement was higher than those with 15cm and 30cm deep drip-tape placement. The placement depth of drip-tape would affect both the grain yield and fresh ear yield of spring maize significantly. The grain yields of spring maize in plot T with 15cm and 30cm deep placement were 10. 1%, 11. 6% higher that with 0cm placement, respectively. The fresh ear yields of spring maize with 15cm and 30cm deep placement were 5.6% , 6.6% higher than that with surface drip irrigation, respectively.