集雨栽培冬小麦田土壤水分和矿质氮

在半湿润易旱地区的关中红油土上,研究了垄上覆膜集雨栽培措施对冬小麦(Triticumaestivum)田土壤水分和矿质氮的影响。结果表明覆膜有一定的蓄水保墒效果,冬小麦返青期,0～40cm土壤贮水量覆膜处理比不覆膜处理平均多7.7mm;覆膜能使冬小麦在生长后期更有效地利用土壤深层贮水,在小麦成熟期,100～200cm土壤贮水量覆膜处理比未覆膜处理少23.8mm。覆膜有利于作物对氮肥的吸收利用,氮肥用量相同的处理,覆膜条件下的硝态氮浓度和矿质氮累积量低于不覆膜处理;施氮也可以明显增加土壤剖面中的硝态氮含量和矿质氮累积量。

Effects of rainwater-harvesting cultivation on soil moisture and mineral nitrogen accumulation in field of winter wheat

A field experiment was conducted in a manual loessial soil in middle Shaanxi Province, a sub-humid area prone to drought, to study the effects of rainwater-harvesting cultivation on soil moisture and mineral nitrogen accumulation in field of winter wheat. Ridge-furrow tillage was used, the ridges being mulched by plastic film for rainwater harvesting while the furrows being seeded. The results showed that mulching was effective for water storage and conservation. At reviving stage of winter wheat, water stored in 0~40 cm layer in mulching field was 7.7 mm higher than that in non-mulching field. Mulching was able to improve the plants to use more water in the deeper soil, so water storage in 100~200 cm layer under mulching was decreased by 23.8 mm compared to that under non-mulching. Mulching was beneficial for the crop to absorb and utilize nitrogen fertilizer and to decrease the concentration of NO_3~--N and the mineral nitrogen accumulation in the soil.