中文摘要：

采用野外定位观测、群落调查方法,研究了福建天宝岩国家级自然保护区内分布的长苞铁杉的天然更新即种子的输入与散布。结果表明,长苞铁杉种子雨开始于11月上旬,终止于12月下旬,持续时间约50 d。2003、2004年,种子雨输入的高峰均在11月下旬。空气相对湿度对种子雨日输入密度有显著影响,种子雨输入密度与相对湿度的回归方程为y=337.90-273.5 x（y为种子雨输入密度;x为相对湿度）。不同群落中长苞铁杉种子雨输入密度均存在极显著的年度波动,如在长苞铁杉毛竹混交林中,2003年长苞铁杉种子的输入密度为15.1粒.m-2,2004年为73.9粒.m-2。长苞铁杉的种子雨在树冠下的输入密度均呈现先升后降的趋势,其分布格局符合二项式分布,具有很高的决定系数。长苞铁杉种子雨在近距离内没有明显的方向性。风是长苞铁杉种子远距离被动扩散中最主要的环境营力,长苞铁杉种子在林冠外的扩散距离基本一致,均为25-30 m。

英文摘要：

By field observation and community investigation,input and distribution of seeds,which is the part of natural regeneration of Tsuga longibracteata in Fujian Tianbao National Nature Reserve were studied in this paper.Results showed that,in the first ten days of November,seeds of T.longibracteata matured and began to drop.Seed rain of T.longibracteata lasted about 50 days.In 2003 and 2004,seed rain day input density of T.longibracteata maximized at the last ten days of November.Atmosphere relative humidity had an evident effect on seed day input density,the regressive equation of atmosphere relative humidity and seed day input density is y=337.90-273.5 x（y is seed day input density,x is atmosphere relative humidity）.There was evident year seed input fluctuation in different type of community.For example,the total seed input density of T.longibracteata in T.longibracteata and Phyllostachys heterocycla mixed forest was 15.1 seeds · m-2 in 2003 and 73.9 seeds · m-2 in 2004.The total seed input density under isolated T.longibracteata tree crown increased at first,then decreased.The pattern fit quadratic distribution,with high coefficients of determination.The total seed input density pattern of isolated T.longibracteata tree did not show evident difference in 4 directions（east,west,south and north）.Wind is the primary environmental dispersal power of seeds.The seeds dispersal distance was about 25 to 30 m,ultimately identical in different isolated T.longibracteata trees.