中文摘要：

研究了湖南省会同县森林植被从地带性植被天然常绿阔叶林到杉木人工林再到杉木火力楠混交林的转变过程中土壤微生物生物量碳和酶活性的变化趋势。结果表明：杉木纯林和混交林土壤微生物生物量碳含量均显著低于常绿阔叶林,分别仅为常绿阔叶林的76.8%和71.5%;与天然阔叶林相比,杉木人工林土壤蔗糖酶、脲酶和磷酸酶活性分别降低了35.8%、22.1%和45.1%,而多酚氧化酶活性增高了40.0%;相反,杉木火力楠混交林土壤蔗糖酶、脲酶和磷酸酶活性比杉木纯林分别增加了20.3%、12.6%和67.8%,而土壤多酚氧化酶活性则降低了41.0%;表明森林植被转变对土壤微生物生物量碳和土壤酶活性能够产生较大的影响,不同的树种对土壤微生物生物量碳和土壤酶活性的影响差异较大。

英文摘要：

This paper studied the change trends of soil microbial biomass carbon and enzyme activities in the process of vegetation change from natural evergreen broadleaved forest to Chinese fir （Cunninghamia lanceolata） plantation and then to Chinese fir and Michelia macclurei mixed plantation in Huitong, Hunan Province. During the vegetation change, the soil microbial biomass carbon decreased significantly. The soil microbial biomass carbon in Chinese fir plantation and in Chinese fir and M. macclurei mixed plantation was deceased by 76.8% and 71.5%, respectively, compared with that in natural evergreen broadleaved forest. After the vegetation change from natural evergreen broadleaved forest to Chinese fir plantation, the activities of soil invertase, urease, and phosphatase decreased by 35.8%, 22.1%, and 45.1%, respectively, while the activity of soil polyphenoloxidase increased by 40.0%. On the contrary, after the vegetation change from Chinese fir plantation to Chinese fir and M. macclurei mixed plantation, the activities of soil invertase, urease, and phosphatase increased by 20.3%, 12.6%, and 67.8%, respectively, while the activity of soil polyphenoloxidase decreased by 41.0%. The results showed that forest vegetation change greatly affected soil microbial biomass carbon and enzyme activities, and the effects varied obviously with tree species.