灌溉方法对温室番茄栽培尿素氮利用影响的研究

用15N示踪技术研究了沟灌和滴灌对温室番茄栽培尿素氮的利用及其在土壤中残留的影响。结果表明,滴灌处理番茄对15N肥料利用率是11.5%(地上部分),沟灌处理15N肥料利用率是7.4%。滴灌处理番茄所吸收的15N肥料量比沟灌处理提高了56.3%,灌溉方式对肥料15N在果实、茎、叶中的分配比例没有明显影响。0~100cm土层中15N肥料残留量滴灌处理为143.1kg/hm2,占氮肥投入量的63.6%,沟灌处理残留量为133.0kg/hm2,占氮肥投入量的59.1%;其中在0~20cm表土层中残留的肥料氮最多,沟灌和滴灌分别达到了79.9kg/hm2和97.3kg/hm2,占0~100cm土层肥料氮残留总量60.1%和68.0%。沟灌处理肥料氮的损失量为75.5kg/hm2,占氮肥投入量的33.5%;滴灌处理肥料氮的损失量为56.0kg/hm2,占氮肥投入量的24.9%。

EFFECTS OF IRRIGATION TECHNIQUES ON ~(15)N-UREA UTILIZATION BY TOMATO IN GREENHOUSE

Effects of drip irrigation and furrow irrigation on the utilization of urea-N in greenhouse tomato were studied by using~(15)N isotope technique.The results showed that fertilizer utilization efficiency of~(15)N were 11.5% for drip irrigation and 7.4% for furrow irrigation treatments.The amounts of~(15)N were taken up by the aboveground part of tomato plant of drip irrigation treatment increased by 56.3% compared to the furrow irrigation treatment.No distinct effects of irrigation techniques on the distribution ratios of~(15)N among the fruits,stems and leaves could be found.The residual amounts of~(15)N in soil depth of 0～100cm was 143.1kg/hm~2 and 133.0kg/hm~2,accounting for 63.6% and 59.1% of the total applied nitrogen fertilizer for the drip irrigation and the furrow irrigation treatments,respectively.In the 0～20cm top soil,the amounts of~(15)N of both treatments which were 79.9kg/hm~2 and 97.3kg/hm~2,being greater than these in other layers,accounted for 60.1% and 68.0% of the amount in 0～100cm layer,respectively.The loss rates of N were 75.5kg/hm~2 and 56.0kg/hm~2 for furrow irrigation and drip irrigation,and occupied 33.5% and 24.9% of the total applied N fertilizer,respectively.