柳杉苗木综合营养诊断研究 Ⅱ.田间DRIS指数法

Study on diagnosis and recommendation integrated system of Cryptomeria fortunei seedlings Ⅱ.Indexes method of DRIS in fields

在田间试验条件下,采用N、P、K三元二次旋转回归施肥设计,建立三元二次旋转回归产量模型,将1年生柳杉苗木按现实生物量的差异,划分2种不同的产量类型,同时结合室内养分含量分析,建立柳杉苗期DR IS指数诊断体系.结果表明,配比施肥对田间柳杉苗木的生物量积累有很大影响,柳杉苗木产量最优解为8.88 g.株-1,对应最佳施肥配方为氮、磷、钾施肥量(养分量)为94.60,44.48,57.50 kg.hm-2.DR IS指数分析表明柳杉苗期对氮、磷、钾各营养元素的需要次序和程度,结果不受柳杉苗龄、叶位的限制.

By application of the ternary quadratic rotary recursive fertilizer design of N, P and K, a output model was established and two outputs types of were divided by the real biomass of one-aged Cryptomeriafortunei seedlings in field. Meanwhile, DRIS indexes diagnosis system was established by the data of N, P and K nutrient elements contents of the seedlings. The results showed that there was an obvious impact of proportioning fertilization on the biomass accumulation of C. fortunei seedlings. The optimal solution of the seedlings outputs was 8. 88 g per tree, and respective quantifies formulation of fertilization was 94. 60 kg. hm^-2 N, 44. 48 kg·hm^-2P and 57. 50 kg·hm^-2 K. The analysis of DRIS indexes showed the sequence and degree of nutrients demanding, and the diagnosis results weren＇t affected by the seedlings age and the sampling position of the leaves.