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对四川省盐亭县桤柏混交林单株干重、平均净生产量、林分生物量和生产力动态的系统研究表明：桤木和柏木不同器官生物量随年龄积累变异显著，积累最多的是树干，其它器官积累较少。桤木各器官平均净生产量在２～１２年上升，在１２～１４年左右达到峰值，随后下降，其生物量结构和垂直分布也呈相同的趋势，表明桤木在１６年以后已成熟，主伐年龄可定在１８～２０年间。柏木叶积累量的增长在幼龄期有“超前现象”，其各器官平均净生产量在２～１８年内增和或“Ｊ”型曲线，生物量结构和垂直分布仍处于剧烈分化期。在我国人工混交林中，桤柏混交林的生物量和生产力都比较高。
Systematic studies on dry weight per plant, average net production, stand biomass and productivity in the mixed plantations of Y. and Y. In Yanting County, Sichuan Province showed that the biomass of different organs of Alnus cremastogyne and Cedar varied significantly with age, with the most accumulated Trunk, less accumulation of other organs. The average net production of Alnus cremastogyne increased from 2 to 12 years and peaked at around 12 to 14 years, then decreased. The biomass structure and vertical distribution also showed the same trend, indicating that alnus was mature after 16 years, The cutting age can be set at 18 to 20 years. The accumulation of cypress leaves had a “leading phenomenon” in young age. The average net production of various organs increased or “J” shaped within 2 to 18 years, and the biomass structure and vertical distribution were still in a period of severe differentiation. In our mixed plantation, the biomass and productivity of mixed plantation are higher.