缓释氮肥在茶园中施用效果研究

目的]了解缓释氮肥在茶园中的施用效果。方法]设置尿素(CK)、包膜肥、包膜肥减氮量20%、包膜肥+双氰胺(DCD)4个处理,对茶叶产量、含氮量、品质和土壤氮含量进行分析比较。结果]尿素处理的茶叶产量最高,达14599.5kg/hm2,包膜肥、包膜肥减量和包膜肥+DCD处理的产量分别比对照减少2.6%、4.3%和8.1%。茶树功能叶的氮含量比较稳定,在3.08%～3.94%。不同处理对茶叶的品质未造成明显的影响。尿素处理的土壤铵态氮和硝态氮含量均与施用时间及次数有关,包膜肥处理的土壤铵态氮和硝态氮含量都是春茶期间较高,以后逐步下降。包膜肥减量处理的土壤中铵态氮和硝态氮含量较少。包膜肥中加入DCD之后,硝化作用明显被抑制,土壤中硝态氮含量明显下降,铵态氮含量相对有所增加。结论]该研究为进一步开发和应用新的肥料品种提供依据。

Study on the Application Effect of Slow-release Nitrogen Fertilizer in Tea Garden

Objective] The study aimed to know the application effect of slow-release N fertilizer in tea garden. Method] 4 treatments of urea (CK), coated fertilizer, coated fertilizer with N content being reduced 20 %, coated fertilizer + dicyandiamide (DCD) were set up and the yield, N content and quality of tea and N content in soil were analyzed and compared. Result] The tea yield in urea treatment was highest, reaching 14 599.5 kg/hm2. Compared with CK, the yields in the treatments of coated fertilizer, coated fertilizer reduced N content and coated fertilizer + DCD reduced 2.6 %, 4.3 % and 8.1 % resp. The N content in functional leaves of tea tree was comparatively steady, in 3.08 %～3.94 %. Different treatments caused no obvious effect on tea quality. Both ammonium-N and nitrate-N contents in soil treated with urea related to application time and times, that in soil treated with coated fertilizer were higher during spring tea period and then decreased gradually and that in soil treated with coated fertilizer reduced N content were less. After adding DCD into coated fertilizer, the nitrification was obviously inhibited, the nitrate-N content decreased obviously and the ammonium-N content had some increase in soil comparatively. Conclusion] The research provided basis for further developing and applying new kinds of fertilizers.