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生物多样性维护是人工林经营考虑的重要因素,而林龄变化与人为干扰是人工林林下植被生物多样性的重要影响因素。以秦岭西段小陇山林区日本落叶松(Larix leptalepis)人工林为研究对象,采用Simpson指数、Shannon-Wiener多样性指数(H)、Brillouin指数(H)、均匀度、McIntosh指数(D_(MC)),分析林下植被随林龄变化和不同生长期人为干扰对其多样性的影响。结果表明:日本落叶松人工纯林生物多样性各指数随林龄和人为干扰的影响,其变化趋势基本保持一致。随林龄的变化和不同时期的干扰影响,灌木层的多样性指数最大出现在林龄30a,草本层最大出现在林龄10a,更新层林龄25a时出现最大。林下植被灌木层多样性变化随林分乔木层密度的减小而增大,随郁闭度的增大而降低;草本层则是先增大后减小的趋势。
Maintaining biodiversity is an important factor in plantation management, and the change of age and man-made disturbance are important factors affecting the biodiversity of plantations. Taking Larix leptalepis plantation in Xiaolongshan forest area in the west section of Qinling as an example, the Simpson index, Shannon-Wiener diversity index (H), Brillouin index (H), evenness and Mc_ntosh index )), And analyzed the effects of subtropical forest on its diversity with the change of stand ages and man-made disturbance at different growth stages. The results showed that the variation trend of the index of Biodistribution of Larix kaempferi plantation remained the same with age and man-made disturbance. With the change of forest age and the influence of disturbance in different periods, the diversity index of shrub layer appeared in the maximum of 30 years of age, the maximum appeared in the age of 10 years in the herb layer and the age of 25 years in the regeneration layer. The diversity of undergrowth shrub layer increased with the decrease of arbor layer density, and decreased with the increase of canopy cover degree. The herb layer firstly increased and then decreased.