[目的]研究新疆天山云杉Picea schrenkiana var。tianschanica种子雨时空动态分布规律和种子萌发状况，为预测森林群落的演替趋势，并为保护天山森林生态系统的物种多样性提供科学依据。[方法]在林场设置3块面积为1 hm2天然林永久固定监测样地，采用机械布局的方法以10m×10m的样方为单位，在样方中心设置1个种子雨收集器，每个样地共100个收集器。采用方差/均值(Cx)、负二项指数(K)、聚集度指标(I)、Cassie R M指标(CA)等4种空间分布类型评价方法判别种子雨空间分布状态。此外，进行种子萌发试验，分别测定种子千粒重、发芽势和发芽率。[结果]9月下旬至10月中旬散种量较高;2022年的种子雨总量极显著高于2021年的种子雨总量;Cx为2 047。01、K为1。02、I为2046。01、CA为0。99，4个指标均显示种子空间分布呈聚集分布;各样地高峰期的天山云杉种子千粒重显著高于初始期和末尾期的天山云杉种子千粒重;而种子雨初始期和高峰期的种子平均发芽势与平均发芽率差异不显著，但都显著高于末尾期的种子的平均发芽势和平均发芽率。[结论]天山云杉种子的散种量存在较大的年际变化，且种子空间分布呈聚集分布，落种高峰期为9月下旬至10月中旬，此时种子质量最大，平均发芽率和发芽势最高。图5表1参29
Spatiotemporal dynamic distribution of seed rain and seed germination characteristics of Picea schrenkiana var.tianschanica in Xinjiang
[Objective]In order to provide scientific basis for predicting the succession trend of forest community and protecting the species diversity of ecosystem in Tianshan,this study focus on the spatiotemporal distribution of seed rain and seed germination of Picea schrenkiana var.tianschabica(Tianshan spruce)in Tianshan,Xinjiang.[Method]Based on three sample plots,1 hm2 each set in the Xinjiang agricultural university experimental forest farm,and a seed rain collector was set in the center of each 10 m×10 m sample plot by mechanical layout method,with a total of 100 collectors in each sample plot.Using variance/mean(Cx),negative binomial index(K),aggregation index David(I),and Cassie R M,index(CA),4 evaluation methods to distinguish the spatial distribution state of seed rain.In addition,the seed germination experiment 1 000-grain seed mass,germination energy and germination rate were measured respectively.[Result]The peak period of seed falling of Picea schrenkiana var.tianschanica was from late September to mid-October.The total amount of seed rain in 2022 was significantly higher than that in 2021.The seeds of Tianshan spruce presented aggregation distribution at the spatial level based on 4 indexes,Cx reaching 2 047.01,K reaching 1.02,I reaching 2 046.01,and CA reaching 0.99 respectively.The 1 000-grain mass of spruce seed in the peak period was significantly higher than in the initial stage and the end stage.There was no significant in seed gernination energy and gernination rates between the initial period and period,but were significantly higher than the ending time of the rain.[Conclusion]The interannual variation characteristics of seed rain of Tianshan spruce obviously showed an aggregated distribution.The peak period of seed rain was from late September to mid-October,the 1 000-grain mass,the germination energy and average germination rate were the best during this period.[Ch,5 fig.1 tab.29 ref.]
万方数据
维普
