氮转化的生化调控对蔬菜生长及土壤质量的影响

采用微区试验方法,研究了温室栽培条件下新型脲酶抑制LNS、硝化抑制剂双氰胺(DCD)与尿素配合施用对蔬菜产量、品质及菜田土壤pH、电导率的影响.结果表明,两种抑制剂配合施用对芹菜产量和Vc含量影响不大,但却显著降低了芹菜的硝酸盐含量,提高了下茬生菜产量.一季氮肥的施用就使温室土壤表现出了明显的酸化和盐分表积趋势,但两种抑制剂与尿素配合施用可以使土壤酸化程度明显减缓.芹菜定植后1个月时,U UI NI处理的土壤pH与U和U UI相比,分别提高了0.7和0.52个pH单位,差异极显著(P < 0.01);第二茬生菜收获后,土壤电导率值与二者相比,分别降低了17.67%和17.00%.因此,脲酶和硝化抑制剂配合施用调控氮素转化可能是缓解设施农业生产中的土壤酸化和次生盐渍化、降低蔬菜硝酸盐含量的一项有效措施.

Effects of biochemical regulation of nitrogen on vegetables growth and soil quality

Based on a microplot experiment in greenhouse,this paper discusses the synergistic effects of new urease inhibitor LNS in cooperation with nitrification inhibitor dicyandiamide(DCD) on the yield and quality of vegetables,soil pH and electrical conductivity(EC.) The results indicate that a combined application of LNS and DCD has little effect on the yield and Vc content of celery,but reduces the nitrate content of celery and increases the yield of lettuce obviously.Applying N fertilizer could accelerate soil acidification and secondary salinity.While a combined application of LNS and DCD could make soil acidification and secondary salinity slow down.After 1 month of celery transplanted,soil pH in treatment U UI NI is enhanced by 0.70 and 0.52,compared with U and U UI,respectively(P < 0.01),and the soil EC value is reduced by 17.67% and 17.00% after lettuce harvest.