Seed rain in a North American tall grass prairie.
Seed rain in a North American tall grass prairie.
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北美高草草原上的种子雨。
DOI：
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发表时间：
1980
期刊：
影响因子：
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通讯作者：
Jody K. Rapp
中科院分区：
文献类型：
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作者：
D. Rabinowitz;Jody K. Rapp
(1)1978年，为了测量北美天然草地的全年种子雨总量，50个直径为9 cm的粘性陷阱暴露于收集分散繁殖体26周。(2)捕获19700粒种子m-2（对于ln-转换数据，每个捕获器，x = 126，x s = 91，x + s = 173）。这一数字是高得多（由两个数量级）比以前的报告为非草原栖息地，但被低估，因为植被部分掩盖了陷阱表面，因为扩散继续到冬季时，陷阱成为积雪覆盖。(3)两种双子叶植物（主要是一枝黄花）的扩散活动都有两个高峰，一个在初夏，另一个在初秋。和紫菀属（Aster spp.）和暖季草。每周落下的种子数量与前一周的风力强度弱相关。(4)30个分类群被鉴定为种，两个分类群被集中，可能包含另外9个种。物种之间捕获的种子数量的分布似乎均匀的对数类（强烈右偏算术类）。(5)种子雨在空间上是斑块状的，这一结果可能会强烈影响随后的幼苗相互作用。(6)种子雨的物种组成在质量上更接近开花群落比它更像土壤中的种子库。从雨水到土壤池的种子密度减少了71%。
(1) In order to measure total annual seed rain for a native grassland in North America, fifty 9 cm diameter sticky traps were exposed to collect dispersing propagules for 26 weeks in 1978. (2) 19 700 seeds m-2 were trapped (per trap for ln-transformed data, x = 126, x s = 91, x + s = 173). This figure is much higher (by two orders of magnitude) than previous reports for non-grassland habitats, but is an underestimate because vegetation partially obscured the trap surfaces and because dispersal continued into the winter when the traps became snow-covered. (3) There were two peaks of dispersal activity: one in early summer for graminoid species and another in early autumn for both dicots (mostly Solidago spp. and Aster spp.) and warm season grasses. The number of seeds falling per week is weakly correlated with the strength of wind for the previous week. (4) Thirty taxa were identified to species, and two taxa were lumped, probably containing an additional nine species. The distribution of the number of seeds caught among species appears uniform for logarithmic classes (strongly right skewed for arithmetic classes). (5) The seed rain was spatially patchy, and this result may strongly influence subsequent seedling interactions. (6) The species composition of the seed rain qualitatively resembled the flowering community much more closely than it resembled the seed pool in the soil. There is a 71 % reduction of seed density from the rain to the soil pool.