不同供氮水平对喜树造林幼树生长的影响

Effects of nitrogen application on the growth of Camptotheca acuminata seedlings

以喜树幼林为试验材料,在田间条件下施以不同水平的氮素,测定了苗高、地径、根长、生根数、生物量等的变化规律,探讨了不同氮素水平对喜树生长的影响。结果表明,随着供氮水平的增加,喜树的苗高、地径、根长、生物量、叶片数都呈现先升高后下降的变化趋势,均在N3水平(30 g/株)到达峰值。生根数则呈现先下降后上升的趋势,在N3水平处于最低值。在整个生长过程中,对照处理的各项指标始终保持较低水平。综合各项生长指标,认为适量的氮素水平有利于喜树的生长。

A field experiment was carried out to investigate the effects of different nitrogen on growth of Camptotheca acuminata seedlings. The height, ground diameter, root length, root number and biomass were analyzed on C. acuminata seedlings. The results showed that along with increasing of nitrogen levels provided, content of height, ground diameter, root length and leaf number of C. acuminata increased initially and then decreased, N3 （30 g/plant） was the highest. The root number de- creased initially and then increased, N3 was the lowest. Throughout the growth process, the indicators of control always remained low. Integrated indicators, considered that the right amount of nitrogen levels will help to improve the C. acuminata growth.