落叶松幼中龄林主要测树因子生长规律的研究

落叶松是一个分布广,易栽培,早期生长快的树种,因此,研究落叶松幼、中龄林主要测树因子的生长规律,对落叶松的早期管理有着很重要的指导意义。结果表明,落叶松幼、中龄林的主测树因子呈幂函数型生长曲线,其直径平均生长量多在0.4 cm以上,树高平均生长量均在0.4 m以上,而在20 a后,材积平均生长量高达0.002 m3。

Effects of Fertilization on Young Populus deltoids cv. Zhonghua Hongye Growth

Using complete and orthogonal design, fertilization trials were conducted for the young growth of Populus deltoids cv. Zhonghua hongye in the fluviogenic soil in Xindu District, Chengdu City. The results showed that the application ef- fect of the single nutrient elements ranked as K〉N〉P, and that of the fertilization combinations ranked as N＋P＋K〉N＋K〉N＋P, P＋K. The optimum fertilization formula was urea [（NH2）2CO, 150 g/plant] ＋ calcium superphosphate [Ca（H2PO4）2.H20, 220 g/plant] ＋ potassium sulphate （K2SO4, 75 g/plant）.