中文摘要：

通过大田试验,考察了旱地垄沟覆膜栽培对土壤硝酸盐时空分布和玉米生物性状及产量的影响。试验设计了垄沟覆膜、平作不覆膜、平作覆膜和裸地对照4个处理,并对其土壤水分、硝酸盐的时空分布和玉米产量进行研究。结果表明：在整个玉米生长季,垄沟覆膜栽培模式下土壤0～40 cm土层含水量显著高于平作不覆膜;NO3^--N主要集中在0～40 cm土层,且垄沟覆膜-垄上NO3^--N表聚现象比其它处理更明显,10 cm处垄上NO3^--N含量是沟内的1.6倍、平作不覆膜的2倍;垄沟覆膜和平作覆膜比平作不覆膜处理单株干物质量分别增加了36.15%、16.11%;单株含氮量分别增加了13.97%、3.59%;垄沟覆膜产量高于其他处理。垄沟覆膜栽培能够在保持作物生长状况良好,获得较高产量的同时,增加作物对氮素的吸收利用,同时增加NO3^--N的表层累积,将其保持在根区,从而降低了NO3^--N淋洗的发生,降低环境风险,是旱区获得经济和环境双重效益的玉米栽培模式。

英文摘要：

A field experiment was conducted to investigate the effects of plastic film mulching on spatio-temporal distribution of soil nitrate and maize yield in drylands. Four treatments,including（ 1） Alternating ridges and furrow,the ridge mulched（ RM）;（ 2） Flat plot with mulching（ PM）;（ 3） Flat plot without mulching（ PNM）;（ 4） Flat plot without planting（ CK）,were carried out to examinethe impact of tillage and mulching treatments on soil moisture,soil nitrate content（ NO3^-- N）,maize biological characteristics and yield. Result showed that soil moisture content under mulching on 0 ～ 40 cm layer were significantly higher than that in the treatment without mulching. NO3^-- N mainly accumulated in 0 ～ 40 cm soil layer under mulching which the NO3^-- N content in 10 cm soil layer was 1. 6 times higher in RM-ridge that in 10 cm soil layer in RM-furrow,and 2 times higher in 10 cm soil layer in PNM. The highest maize yield was observed in the RM treatment（ but not significant）. The plant dry matter in RM and PM were increased by 36. 15% and 16. 11% than PNM,and nitrogen per plant were increased by 13. 97% and 3. 59%. It was concluded that the RM treatment could keep NO3^-- N in the root zone（ 0 ～ 40 cm）,reduce NO3^-- N leaching. Therefore,the RM treatment（ alternating ridges and furrow,the ridge mulched）was recommended for maize cultivation in dryland which was win-win for economy and environment.