不同灌溉与施氮措施对露地菜田土壤无机氮残留的影响

在华北地区露地生产条件下 ,通过监测 5季轮作蔬菜 (苋菜 -菠菜 -花椰菜 -苋菜 -菠菜 )的产量和土壤无机N(Nmin)的变化 ,比较了传统的和采用平衡方法进行推荐的水分和N素处理对土壤Nmin残留数量的影响。结果表明 ,除花椰菜试验外 ,传统N素处理与推荐的N素处理在蔬菜产量上没有显著差异 ,但传统的N素处理皆可导致深层土体中Nmin的大量累积。在 4季蔬菜轮作后 ,传统灌溉措施条件下的N素处理都不同程度地造成了土体的N素淋失 ,所影响的土层深度已经达到了 150～ 180cm土层 ,然而采用平衡方法进行推荐的水分和N素处理组合对土体深层土壤中Nmin残留数量没有造成明显的影响

Effects of different irrigation and fertilization strategies on soil inorganic N residues in open field of vegetable rotation system

Effects of different irrigation and fertilization strategies including conventional treatment and recommended treatment following balancing method on the total yield of five seasonal vegetable rotation system (amaranth-spinach-cauliflower-amaranth-spinach) and the changes of soil N_min residue were compared in North China Plain in this paper. The results showed that there were no significant differences in marketable yield between conventional and recommended nitrogn treatments except for cauliflower in 2000yr. In conventional nitrogen treatments with different irrigation regimes, much soil nitrate was accumulated and leached down to the depth of 150～180cm after four seasonal vegetable experiments. However, no obvious nitrogen leaching was monitored in the combination with recommended water and nitrogen treatments.