<正>以长序榆种子育苗为对象 ,研究苗木年生长规律。采用有序样本聚类分析法划分苗木的生长时期 ,拟合了高、径生长的 L ogistic方程 ,找出苗高、地径及主根生长之间的最优回归方程 ,了解苗木各部分生长的相关关系。多元回归分析表明 ,气温是影响苗木生长的主导因子

This article deals with the annual growth rhythm of Ulmus elongata seedlings.The four growth periods were divided for the seedlings by using cluster analyses of series samples.The results showed that the logistic equations were fitted for the growth of height and diameter,the optimum regression equation was found for the growth of seedlings height,diameter and main root,and the relations of each part growth of the seedlings were also revealed.The multivariate regression analysis indicated that the temperature was the main factor in influencing the growth of Ulmus elongata seedlings.