Local-scale synchrony and variability in mast seed production patterns of Picea glauca
Local-scale synchrony and variability in mast seed production patterns of Picea glauca
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DOI：
10.1111/j.1365-2745.2007.01266.x
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发表时间：
2007-09-01
影响因子：
5.5
通讯作者：
Boutin, Stan
中科院分区：
文献类型：
--
作者：
Lamontagne, Jalene M.;Boutin, Stan
1. 桅杆播种是由一群植物同步和高度可变的种子生产。桅杆播种源于个体的行为；然而，人们对个体在局部尺度上的同步性知之甚少。我们在种群内（17-36公顷的研究地块）和个体水平上解决了两个主要问题：(i)种子产量在年份之间和年内的变化程度如何？（二）个体间种子生产的同步性如何？对加拿大育空地区4个样地356株云杉（Picea glauca）在1990 - 2005年间的球果产量进行了监测。采用Spearman相关（r(s)）检验同步性。总体而言，树木在所有距离上都是中度同步的(平均r(s) （+/- SE）为0.52 +/- 0.14)，并且在统计学上可以检测到同步（r(s) >）。距离< 75 m的个体高度同步（0.64 +/- 0.18），而距离> 3 km的个体相关性降至0.33 +/- 0.07。不同个体间的产果模式差异较大。每个地块的丰年数从1年到3年不等。在丰收年，地块内的许多个体产量较大，在丰收年，个体间的差异较大。单株树的显性内源周期从0 ~ 1 ~ 5年不等。44%的树没有明显的滞后，23%的树有1年的负滞后，20%的树有3年的正滞后。基部面积不影响滞后，但在整个研究过程中，平均球果产量较高的树木与没有滞后的树木相比，更有可能有3年的滞后。最高同步性的尺度与该地区的主要种子捕食者——领地红松鼠（Tamiasciurus hudsonicus）的活动尺度一致。这可能是同步选择发生的尺度。基于局部的高同步性、丰年内的高同步性以及个体锥体生产的多重滞后，可用资源和强烈的天气线索似乎在观测到的模式中发挥了作用。
1. Mast seeding is the synchronous and highly variable production of seed by a population of plants. Mast seeding results from the behaviour of individuals; however, little is known about the synchrony of individuals at local scales.2. We address two primary questions at a within-population (17-36 ha study plots) and individual level: (i) How variable is seed production between and within years? (ii) How synchronized is seed production between individuals?3. We monitored annual cone production of 356 Picea glauca (white spruce) from 1990 to 2005 within four plots spanning a total distance of 5.3 km in the Yukon Territory, Canada.4. Spearman correlations (r(s)) were conducted to test for synchrony. Overall, the trees were moderately synchronous (mean r(s) (+/- SE) of 0.52 +/- 0.14), and synchrony was statistically detectable (r(s) > 0) over all distances. Individuals < 75 m apart were highly synchronous (0.64 +/- 0.18), and correlations dropped to 0.33 +/- 0.07 for trees > 3 km apart. There was considerable variation in cone production patterns among pairs of individuals.5. The number of mast years per plot varied from one to three. During a mast year, many individuals within plots produced large cone crops, with more variability between individuals in low mean cone years. Individual trees had dominant endogenous cycles varying from none to 1-5 years. Forty-four per cent of trees had no significant lag, 23% a negative 1-year lag, and 20% a positive 3-year lag. Basal area did not influence lags, but trees with higher mean cone production throughout the study were more likely to have a 3-year lag compared with no lag.6. The scale of highest synchrony coincided with the scale at which the dominant seed predator in the area, the territorial red squirrel (Tamiasciurus hudsonicus), operates. This may be the scale at which selection for synchrony occurs.7. Based on high synchrony locally, high synchrony within a mast year, and multiple lags in cone production by individuals, both available resources and strong weather cues appear to play roles in the observed patterns.