贵州马尾松群落植物多样性与土壤酶活性

Plant diversity and soil enzyme activity in 4 typical communities of Pinus massoniana in Guizhou

以贵州4种典型马尾松群落类型为研究对象,对不同马尾松林下植物多样性和土壤酶活性及二者之间相互关系进行研究。结果表明:(1)不同马尾松群落植被种类差异显著,其中马尾松杉木混交林植物种类最多,为23种,马尾松硬阔混交林最少,仅11种。对4个物种多样性指数的综合分析表明,灌木层物种多样性高于草本层,群落中物种多样性整体表现为马尾松杉木混交林>天然次生纯林>人工纯林>马尾松阔叶混交林;(2)不同群落间土壤理化性质差异显著,混交林土壤有机质、全氮、碱解氮和有效磷含量均高于纯林,p H值则相反,有机质和有效磷与灌木层植物多样性指数呈显著负相关(P<0.01),全钾含量与草本层植物多样性指数呈显著正相关(P<0.01);(3)不同马尾松群落土壤多酚氧化酶和酸性磷酸酶差异不显著,脲酶、β-葡萄糖苷酶和纤维素酶活性差异显著,且与土壤全氮、碱解氮或全磷呈显著相关,这3种酶可作为不同马尾松群落类型土壤肥力状况和质量的生物学指标。

The differcence and relationship between vegetation composition and soil enzyme activity of 4 different Pinus massoniana communities in Guizhou Province were investigated. The results showed as follows. （1） The plant species richness varied significantly among different communities, the mixed forest of Pinus massoniana and Cunninghamia lanceolata had the most plant species with 23, the Pinus massoniana and broad leaf tree mixed forest had the fewest species with only 11. According to comprehensive analysis of 4 species diversity indexes, the species richness of shrub layer was higher than that of herb layer and the plant species diversity of 4 Pinus massoniana communities could be ranked as Pinus massoniana and Cunninghamia lanceolata mixed forest〉natural secondary〉Pinus massoniana plantation〉Pinus massoniana and broad leaf tree mixed forest. （ 2） The physical and chemical properties of soil varied among different communities, mixed forests were higher than Pinus massoniana monoculture at the levels of soil organic matter, soil total nitrogen, alkali-hydrolyzable nitrogen and available phosphorus, but pH value was contrary, and there was signifi-cant negative correlation （ P〈0.01） between the soil organic matter and available phosphorus and the shrub layer plant diversity index, while there was significant positive correlation （ P〈0.01） between the soil total potassium and the herb layer plant diversity index. （ 3） The activities of soil polyphenol oxidase and acid phosphatase were similiar among different communities, while the activities of soil urease,β-glucosidase and cellulase varied significantly. The activities of soil urease, β-glucosidase and cellulase were significantly correlated with soil total nitrogen, alkali-hydrolyzable nitrogen and total phosphorus, indicating their potential roles in representing soil nutrient status and evaluating soil health in Pinus massoniana communities.