重庆四面山常绿阔叶林建群种种子雨、种子库研究

Seed rain and seed bank of constructive species in evergreen broadleaved forest at Chongqing Simian Mountain.

对重庆四面山常绿阔叶林建群种种子雨、种子库的研究表明,建群种早期和晚期的种子雨无活力;种子偏早或偏晚成熟及大籽粒的树种,其种子雨被取食的比例大;种子雨、有活力种子雨、种子库三者的数量变化不一致;有活力种子雨量较大的栲、石栎、小叶青冈、扁刺栲、香桂等,其种子库密度在早期以近几何级数的方式增长,元江栲、银木荷种子库小,存在时间短,翌年无一年生萌发苗;种子库数量动态、消减率动态决定于种子被取食的强度、种子衰老的速度以及种子对病菌、逆境的抗性和种子萌发的整齐性.

The study shows that the early and late seed rains of constructive tree species in evergreen broadleaved forest at Chongqing Simian Mountain had no activity.The bigger the seeds of the species and the earlier or later the seeds of the species matured,the higher the proportion of the seed rain damaged by animals.The quantitative variation of seed rain,active seed rain and seed bank did not take place at the same time.At early time, the number of seed banks of Castanopsis fargesii,Lithocarpus glabra,Quercus myrsinrefolia,Castanopsis plasyacantha,Cinamomum subavenium . which own more active seed rain increased by geomitric series.The seed banks of Castanopsis orthacantha and Schima argentea were small,only survived a short time,and did not sprout next year.The quantitative dynamics of seed banks and their increasing or decreasing rates were decided by the proportion damaged by animals,dying speed of seeds and their resistance to pathogens and adverse circumstances,and the state of seed germination.