不同施氮措施对保护地黄瓜养分利用效率及土壤氮素淋失影响

Effects of Different Fertilizer Measurement on Nutrient Utilization in Cucumber and Nitrate Leaching Loss from Soil in Greenhouse

不同施氮措施条件下,对保护地黄瓜生育期内氮素吸收利用效率、氮素淋洗损失进行了研究,同时也研究了不同处理对黄瓜产量及品质的影响。试验结果表明,传统施肥处理(2100 kg/hm2)与推荐施肥处理(900 kg/hm2)之间氮素吸收量没有显著差异,传统施肥处理中大量的氮肥没有用于促进黄瓜对养分的吸收利用,其氮肥利用率、农学利用率以及生理利用率都很低,每千克纯氮增产只有2.06 kg,91.65%的氮素以各种途径被损失掉,其中土壤硝态氮淋洗是主要形式。同时研究发现,传统施肥处理过量氮肥施用阻碍其它营养元素的吸收,降低N,P,K养分的利用率。从产量和品质看,减少氮的用量,黄瓜产量会降低,但推荐施肥与传统施肥处理差异不明显,而推荐施肥能提高果实中Vc含量、有效酸度(pH),改善黄瓜的口感。

Effects of applying different nitrogen fertilizer on yield, quality and nitrate leaching in soil layer were studied during the cucumber growth period in greenhouse. The result showed that N uptake was not significant difference between conventional nitrogen treatment and optimum treatment. RE, PE and AE of conventional nitrogen treatment were lower than optimum treatment and 91.65% of applied N was lost by the kind of ways. Nitrate leaching loss was the dominant factor. It is also found that nitrogen applying with conventional treatment inhibited the absorption of other nutrients. In the term of yield and quality of cucumber, optimum treatment （N2） were not different from the conventional fertilizer treatment, but it could increase Vc content and active acidity （pH）.