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本文于2005年5月份,在中国科学院会同森林生态实验站选择了一块 15 年生的杉木纯林和两块 15 年生杉阔混交林作为研究对象,调查了林地土壤有机碳、全氮、全磷、硝态氮、有效磷和土壤微生物碳、氮、磷、基础呼吸以及呼吸熵,比较了纯林和混交林土壤微生物特性和土壤养分。结果表明,杉阔混交林的土壤有机碳、全氮、全磷硝态氮和有效磷含量高于杉木纯林;在混交林中,土壤微生物学特性得到改善。在 0-10 cm 和 10-20 cm 两层土壤中,杉阔混交林土壤微生物氮含量分别比杉木纯林高 69%和 61%。在 0?10 cm 土层,杉阔混交林土壤微生物碳、磷和基础呼吸分别比杉木纯林高11%、14%和 4%;在 10?20 cm 土层,分别高 6%、3%和 3%。但是,杉阔混交林土壤微生物碳:氮比和呼吸熵较杉木纯林低34%和 4%。另外,土壤微生物与土壤养分的相关性高于土壤呼吸、微生物碳:氮比和呼吸熵与土壤养分的相关性。由此可知,在针叶纯林中引入阔叶树后,土壤肥力得以改善,并有利于退化森林土壤的恢复。
In May 2005, a 15-year-old Chinese fir plantation and two 15-year-old Chinese fir mixed broad-leaved mixed forests were selected as research objects at the Forest Ecology Experiment Station, Chinese Academy of Sciences. The contents of soil organic carbon, total nitrogen, total phosphorus, Nitrate nitrogen, available phosphorus, and soil microbial carbon, nitrogen, phosphorus, respiratory and respiratory entropies. Soil microbial properties and soil nutrients in pure and mixed forests were compared. The results showed that the contents of soil organic carbon, total nitrogen and total phosphorus in the Chinese fir plantation were higher than those in the pure Chinese fir plantation. In the mixed forest, the soil microbial characteristics were improved. In 0-10 cm and 10-20 cm soil layers, the content of soil microbial nitrogen in Chinese fir and broad-leaved mixed forest was 69% and 61% higher than that in pure Chinese fir plantation respectively. In 0 ~ 10 cm soil layer, the soil microbial biomass C, P and basic respiration were higher by 11%, 14% and 4% than those in pure Chinese fir plantation respectively, while in the 10-20 cm soil layer they were 6% and 3% And 3%. However, the soil microbial C: N and respiratory entropy of Cunninghamia lanceolata mixed forest were 34% and 4% lower than those of pure Chinese fir forest. In addition, the correlation between soil microorganisms and soil nutrients was higher than that of soil respiration, microbial C: N and respiratory entropy and soil nutrients. It can be seen that the introduction of broad-leaved trees in coniferous pure forests improves soil fertility and is conducive to the restoration of degraded forest soils.