滇池流域设施条件下生菜氮磷减控研究

STUDY ON NITROGEN AND PHOSPHORUS REDUCTION AND CONTROL IN SHELTER GROUND - CULTIVATED LETTUCE IN THE DRAINAGE AREA OF DIANCHI LAKE

对滇池流域大渔乡的保护地生菜不同氮、磷、钾配比研究的结果表明:氮、磷化肥投入量比习惯施肥量减少 48.7％,生菜增产29.6％。适量和合理的氮、磷、钾配比能提高生菜的紧实度、叶球大小、降低生菜食用部分硝酸盐, 改善生菜品质。减少氮磷化肥用量可以大幅度降低氮磷在土壤中的累积和硝酸盐的含量,减少氮磷的流失风险。

N, P and K were applied in different combinations to lettuce grown in sheltered ground in Dayu Township of the drainage area of Dianchi Lake. The yield of lettuce was increased by 29.6% when the rates of N and P were reduced to 48.7% of the conventional rates adopted by the local farmers. NPK,applied in proper combinations,helped to increase the compactness of lettuce and the size of its head and to decrease the nitrate content of its edible parts,thus improving the quality of the vegetable. Reducing N and P rates also decreased N and P accumulation and nitrate content in the soil and decreased the risk of N and P running off.