缙云山常绿阔叶林种子雨组成及其时空动态

【目的】分析缙云山常绿阔叶林种子雨组成及其时空动态,为常绿阔叶林种子生态学大尺度和长时序的研究提供数据支持,并为受损常绿阔叶林近自然恢复过程中的种源收集和种子撒播提供参考信息。【方法】 2014-01—2016-12,收集缙云山常绿阔叶林1 hm 2标准地中172个种子收集框内的种子,鉴定物种并计数,风干后称质量。根据果实类型及种子特征并结合野外实地观察,确定每个物种种子(果实)的散布方式。【结果】 3年间共收集到成熟种子36 298粒,种子雨密度为140.69粒·m -2 a -1;种子分属于19科21属27种,占群落木本植物物种总数的36.49%;种子雨具有明显的季节动态,在秋季出现高峰,其中有17个物种在干季(1—4和10—12月)成熟并散布,6个物种在湿季(5—9月)成熟并散布,4个物种在干、湿季均有散布;种子雨密度年际变异系数为0.36~1.73,空间变异系数为1.54~15.20。【结论】缙云山种子雨产量在常绿阔叶林中处于较低水平;优势种对群落种子雨产量贡献较大,种子雨物种组成与群落物种组成相似性较低;群落水平种子雨具有明显的季节动态,且存在很大的年际变异和空间变异,反映出亚热带常绿阔叶林种子雨时空动态的典型特征。在区域植被近自然恢复中的种子采集和撒播环节,应当充分参照不同物种的种子雨掉落的时空动态。

Composition and Spatial-Temporal Variation of the Seed Rain in An Evergreen Broad-Leaved Forest on Jinyun Mountain

【Objective】 This study aims to investigate the composition and spatial-temporal variation of the seed rain in an evergreen broad-leaved forest in Jinyun Mountain. This study also aims to provide data support for large-scale and long-term ecological studies on seeds in evergreen broad-leaved forests, as well as to guide the collection of seed sources and to learn the patterns of seed dispersal during the restoration of damaged forests.【Method】 Seeds were collected from January 2014 to December 2016 using 172 seed traps established in a 1hm 2 monitoring plot in Jinyun Mountain. Collected seeds were identified and counted, and seed mass was weighted after being air-dried.【Result】 36 298 mature seeds belonging to 27 species of 21 genera and 19 families were collected in three years. The density of the seed rain was 140.69 seeds · m -2 a -1 . The 27 species accounted for 36.49% of the total number of woody plants within the study plot. The seed rain showed a clear seasonal dynamics and the peak of the seed rain appeared in autumn;17 species released mature seeds in the dry season (from January to April and from October to December), while 6 species released mature seeds in the wet season (from May to September) and 4 species released mature seeds in both dry and wet seasons. The coefficient of interannual variation of the seed rain ranged between 0.36 and 1.73, and the coefficient of spatial variation of the seed rain ranged between 1.54 and 15.20.【Conclusion】 Seed production in Jinyun Mountain was relatively low compared with the other evergreen broad-leaved forests. Collected seeds were mainly from the dominant species of the above-ground plant communities. However, the similarity in species composition between the seed rain and the above-ground plant communities was low. Seed rain showed a clear seasonal dynamic together with a large interannual and spatial variation, which reflected the typical characteristics of the seed rain in subtropical evergreen broad-leaved forests in terms of its spatial and temporal dynamics. This study provides data support for large-scale and long-term studies on seed ecology in evergreen broad-leaved forests. The spatial-temporal dynamics of the seed rain should be carefully referred to when collecting and sowing seeds during forest restoration processes.