杉木乳源木莲混交对地力影响的初步研究

对１０年生乳源木莲与杉木的混交林及杉木纯林的林地枯枝落叶量及分解速率、土壤理化性质等进行调查分析。结果表明：混交林结构林地物理性质优于杉木纯林，土壤水稳性团聚体组成多，土壤疏松多孔；土壤有机质、全Ｎ、全Ｐ分别比杉木纯林提高１２．２％、１１．８％和４．５％，土壤速效养分（Ｎ、Ｐ、Ｋ）亦分别提高２９．６％、１０．５％、１０．１％，该混交对地力改良有积极作用。

Preliminary Research on Effects of the Mixture of Chinese Fir and Manglietia yuyuanensis on the Soil FertiIity

The surveys and analyses of the ground litter amount and its decomposition rate as well as the soil physical and chemical properties were carried out for mixed stands of Manglietia yuyuanensis and Chinese fir and pure stands of Chinese fir at the age of ten. The results showed that the ground physical property of the mixed stands was better than that of the pure Chinese fir stands;their soil was loose and porous;their soilorganic matter,total N and total P were 12.2%,11.8%and 4.5%more than those of the pure Chinese fir stands,respectively; their soil quick-acting nutrients (N, P and K) were 29.6%,10.5%and 10.1%more respectively,too;and thus the mixed stands had a positive effect on the soil fertility improvement.