杉木观光木混交林土壤腐殖质组成及特性

1999年1月对福建三明莘口教学林场杉木观光木混交林及对照杉木纯林土壤腐殖质的有机碳和胡敏酸(HA)含量、HA/FA、可见光谱、红外光谱特性等进行研究。结果表明,与杉木纯林相比,混交林各土层土壤有机碳、胡敏酸含量及胡敏酸的E4值均有显著增加,HA/FA比值亦有所增加(不显著),而E4/E6值略有降低,胡敏酸红外光谱在1650 cm-1处出现明显的吸收峰。可见混交林中土壤腐殖质腐殖化程度和芳香度较纯林的高,这对土壤结构改良和有效养分供应有利,土壤肥力有一定程度的提高。图1表1参17。

Composition and properties of soil humus in a mixed forest ofCunninghamia lanceolata andTsoongiodendron odorum

This study was conducted in Xinkou Experimental Forestry Farm of Fujian Agricultural and Forestry University, Sanming, Fujian Province in January 1999. Taking pure stand of Chinese fir as control, the authors measured and studied the content of organic carbon, content of humic acid (HA), ratio of HA of fulvic acid (FA), and the characteristics of infrared light spectrum and visible light spectrum of soil humus in the mixed forest of Chinese fir and Tsoong’tree. Compared to humus composition in the pure stand of Chinese fir, the content of soil organic C, HA content, and the E₄ value of HA for different layers of soil, except for the ratio of HA to FA, showed a significant increase in the mixed forest, while the ratios of E₄ to E₆ had a little decrease. The infrared light spectrum of humic acid had an absorptive peak at 1650 cm^?1. It is concluded that the levels of humification and aromaticity of soil humus are higher in the mixed forest, which is favorable for the improvement of soil structure and nutrient supply, thus improving the soil fertility to a certain degree.