海南霸王岭陆均松种子雨和土壤种子库特征

为了解陆均松(Dacrydium pierrei)的自然更新能力,对海南霸王岭陆均松进行为期3年的种子雨、种子库及幼苗幼树观测,并分析其与环境因子的关系。结果表明,陆均松种子雨和种子库有效种子数量太少并存在季节性差异;其结实存在大小年现象;种子雨的扩散密度随着距母树距离的增加而逐渐减少;土壤种子库种子数量在枯枝落叶层所占比例最大,但有活力种子数量极少。幼苗幼树适宜生存的海拔范围为800~1 400 m,经度、纬度、坡度与幼苗幼树分布有明显相关性。因此,选择适宜季节采摘种子,提高种源数量和质量,清除林下枯枝落叶,增加种子萌发能力等以减少陆均松更新的限制条件的人工抚育措施应适当考虑。

Characteristics of Seed Rain and Soil Seed Bank of Dacrydium pierrei in Bawangling, Hainan

In order to understand the regeneration ability of Dacrydium pierrei under nature condition, the seed rain, soil seed bank and seedlings and saplings of D. pierrei at Bawangling, Hainan, China were observed for 3 years, and the relationship between environmental factors and the number of seedlings and saplings was analyzed. The results showed that the effective seeds number of seed rain and seed bank of D. pierrei was very litter and had seasonal differences. There was an on-and-off-year phenomenon of fruiting in population. The dispersal density of seed rain gradually decreased with the increment of distance to mother tree. The seed number of soil seed bank in the litter layer accounted for the largest proportion, but the viable seed number was small. The suitable altitude range for seedlings and saplings was from 800 to 1 400 m, and the longitude, latitude, slope had significant correlation with the distribution of seedlings and saplings. Therefore, artificial managements, such as picking seeds in suitable season, improve the quality and quantity of seed sources, and removing litter under forest, enhance seed germination ability, should be considered appropriately for D. pierrei regeneration.