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研究圆齿野鸦椿幼苗年生长节律,为制订合理的苗期管理制度提供理论依据。通过对圆齿野鸦椿一年生苗的苗高、地径生长状况进行持续观测,并利用Logistic、Gompertz模型及其最优组合模型对幼苗苗高、地径年生长规律进行拟合与分析。结果表明:圆齿野鸦椿幼苗苗高与地径生长节律符合“S”型曲线生长的一般规律,Logistic、Gompertz模型和最优组合模型均能较好的模拟圆齿野鸦椿幼苗的年生长节律,但Logistic模型的拟合度(R2)较Gompertz模型拟合度更高,其对苗高、地径的拟合度分别达到0.988、0.985,而最优组合模型能够进一步提高拟合精度。圆齿野鸦椿幼苗生长具有明显的阶段性,苗高出现2次生长高峰,地径出现3次生长高峰,苗高速生期持续64 d左右,速生期生长量占全年生长量的45.36%,地径速生期持续166 d左右,速生期生长量占全年生长量的55.28%,利用Logistic模型,并结合苗木实际生长情况,将圆齿野鸦椿一年生苗年生长划分为4个时期:出苗期、生长初期、速生期和生长后期,并提出各个时期的关键育苗措施。
To study the annual growth rhythm of A. cuspidatum seedlings, provide a theoretical basis for establishing a reasonable management system of seedling stage. Through the continuous observation of the seedling height and diameter growth of one-year-old seedlings, we used Logistic, Gompertz model and the optimal combination model to fit and analyze the annual growth of seedling height and diameter. The results showed that the seedling height and diameter growth rhythm of A. cuspidatum fit the general rule of “S” curve growth. Both Logistic, Gompertz and optimal combination models could simulate the growth of A. cuspidatum (R2) of the Logistic model was higher than that of the Gompertz model, and the fitting degree of the Logistic model to the height and diameter of the seedling reached 0.988 and 0.985, respectively, while the optimal combination model could further improve Co-precision. The growth of Cunninghamia lanceolata seedlings had obvious stage. The height of seedling height appeared twice and the height of seedling height appeared three times. The high-speed seedling stage continued for about 64 days, the growth rate of fast-growing stage accounted for 45.36% , The rapid growth of soil diameter continued for about 166 days, and the annual growth rate accounted for 55.28% of the annual growth rate. According to the Logistic model and the actual growth of seedlings, the annual growth of A. cunninghamii was divided into four periods: Emergence period, early growth period, fast growing period and late growth stage, and put forward the key nursery measures in each period.