Frequency of plant species in remnants of calcareous grassland and their dispersal and persistence characteristics
Frequency of plant species in remnants of calcareous grassland and their dispersal and persistence characteristics
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石灰质草原残迹中植物种类的频率及其扩散和持久特征
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
J. Stöcklin
中科院分区：
文献类型：
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作者：
K. Maurer;W. Durka;J. Stöcklin
Betr.为什么有些物种比其他物种更常见？在这里，我们建议，影响传播和持久性的特征可以用来预测发生的频率在瑞士汝拉山草原残留的物种。我们建立了112种植物在96个残留的石灰质草原在瑞士西北部的发生频率。我们为每个物种确定了以下八个特征：（1）扩散范畴（2）繁殖体的终速，（3）株高，（4）单粒质量，（5）种子形状（长度、宽度和高度的变化），（6）开花开始，（7）开花持续时间，和（8）生活型（无性系多年生植物，多年生植物没有明显的营养繁殖，短命的物种）。然后，我们测试是否有这些性状之间的相关性与发生频率的一个物种在草原残留物使用逐步多元回归与原始数据，以及与遗传学独立的对比（PIC）计算与最近的分子分析的基础上，一个遗传学。开花早（p > 0.01，R-2 = 0.09）、无性系生活型（p > 0.01，R-2 = 0.08）、开花期长（p > 0.02，R-2 = 0.04）和种子重（p > 0.05，R-2 = 0.03）的种类较多。该模型共解释了26个物种频率的变异。结果证实了与PIC分析，除了一个关于生活型。我们的研究结果表明，性状增强持久性更重要的是一个物种在石灰质草原的发生频率比性状影响扩散。这可能意味着，在草原残余殖民远距离扩散是微不足道的，因为缺乏种群之间的繁殖体交换。
Betr. den Nordwestschweizer Jura Why should some species be so much more common than others? Here, we propose that traits affecting dispersal and persistence can be used to predict the frequency of occurrence of a species in grassland remnants in the Swiss Jura Mountains. We established the frequency of occurrence of 112 plant species in 96 remnants of calcareous grassland in NW Switzerland. We determined the following eight traits for each species: (1) dispersal category (unassisted, ant-, adhesion- or wind-dispersed), (2) terminal velocity of diaspores, (3) plant height, (4) mass per seed, (5) seed shape (variance of length, width and height), (6) onset of flowering, (7) duration of flowering, and (8) life form (clonal perennials, perennials without pronounced vegetative reproduction, short-lived species). Then we tested whether there is a correlation among these traits with the frequency of occurrence of a species in grassland remnants using stepwise multiple regression with the original data as well as with phylogenetically independent contrasts (PICs) calculated with a phylogeny based on recent molecular analysis. Species with an early onset of flowering (p > 0.01, R-2 = 0.09), a clonal life form (p > 0.01, R-2 = 0.08), a long duration of flowering (p > 0.02, R-2 = 0.04) and with heavy seeds (p > 0.05, R-2 = 0.03) occurred more frequently than others. In total the model explained 26 variance in species` frequency. Results were confirmed by the analysis with PICs except for the one concerning life form. Our results suggest that traits enhancing persistence are more important for the frequency of occurrence of a species in calcareous grassland than traits affecting dispersal. This might imply that in grassland remnants colonisations by far-distance dispersal are insignificant because of a lack of diaspore exchange among populations.