杉木、火力楠混交幼林养分位移和循环的研究

AN INVESTIGATION ON THE TRANSLOCATION AND CYCLING OF MAIN NUTRIENT ELEMENTS IN YOUNG MIXED STAND OF CUNNINGHAMIA LANCEOLATA AND MICHELIA MACCLUREI

杉木(Cunninghamia lanceloata)是我国特有的优良速生树种,分布广,但连栽出现地力和生长衰退现象。为此,许多地方开展了杉木混交林的试验研究。本文试图通过对广东南亚热带5年生杉木纯林和杉木、火力楠(Michelia macclurei)混交林的养分位移和循环及其枯落物量与分解速率的调查研究,揭示树种组成的种间关系,深入认识混交林生态系统的功能。

In this paper, content of main nutrient elements (N, P, K, Ca, Mg), nutrient translocation, litter and its rate of weight loss during the period of one year in the pure young stand of Cunninghamia lanceolata and the young mixed-stand of C. lanceolata and Michelia macclurei were investigated. From these data, the conceptions of translocation and cycle of the nutrient element, in different stands were obtained. The results showed that the rate of translocation of nutrient elements in the needle leaves of C. lanceolata in pure stands is larger than that in the mixed stand, N contrary. The amount of litter in the mixed stands of C. lanceolata and M. macclurei is larger than that in the pure stands of C. lanceolata, the former is 1 039.95kg/ha.a, the latter 67.00 kg/ha.a. The rate of litter weight loss of C. lanceolata in pure stand and mixed-stand are 80.12 % and 81.08 % respectively. The rate of litter weight loss of M. macclurei is 59.17%. Because the speed of cycle of nutrient elements in the mixed-stand is faster than that in the pure stand, it is beneficial to improve the soil. Therefore, M. macclurei as a tree species for mixed-stand is suitable.