不同水氮管理对菠菜生长和水氮利用的影响

针对传统水肥方式中存在的投入过量问题 ,采用控制耕层土壤湿度以及应用KNS氮素推荐系统对菠菜的产量及水氮利用进行了研究。结果表明 ,推荐施氮处理与传统施氮处理对菠菜的生长没有明显的差异 ,而控制耕层土壤水分含量为植物有效的土壤含水量的 50%～80%及 60%～90%时的处理产量比传统灌水处理有显著性增加。推荐灌水施氮模式同传统灌水施氮模式相比 ,菠菜产量没有明显的差异 ,但是氮素以及水分供应量分别减少了 73.6 %和 39.2% ,相应地水分利用效率提高 64% ,氮素利用效率也有显著提高。推荐的水氮处理在菠菜收获后土壤无机氮残留量比传统处理明显降低。因此在合理灌溉的基础上进行氮素推荐 ,可有效地解决蔬菜生产中产量与环境之间的矛盾

Comparison of conventional and recommended water and nitrogen practices on spinach growth and water and nitrogen usage

The recommended water (by balance method) and nitrogen (by KNS system) practices were compared with conventional practices on spinach growth in field experiment. The results showed that there were no significant differences in spinach recommended and conventional N practices. However, the spinach in the recommended water treatments to control soil moisture in the ranges of 50%～80% and 60%～90% of plant extractable soil water could significantly increased compared to conventional water treatment. In consequence,in recommended water and nitrogen practices, nitrogen and water input amounts were reduced by 73.6% and 39.2%,respectively, of conventional inputs with similar spinach yield, and the residue of inorganic nitrogen in the soil surface layer of recommended water treatment was much lower than that in conventional water treatment. Optimum water strategy could solve the conflict between high yield and environmental protection.