Effects of growing conditions and source habitat on plant traits and functional group definition
Effects of growing conditions and source habitat on plant traits and functional group definition
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DOI：
10.1046/j.1365-2435.2001.00487.x
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发表时间：
2001-02-01
影响因子：
5.2
通讯作者：
Sayre, C
中科院分区：
文献类型：
--
作者：
Dyer, AR;Goldberg, DE;Sayre, C
1.植物功能群被用来描述群落组织的模式。然而，它们被定义为相关性状或物种分组的套件，这两个定义的变化的环境条件的反应是未知的。2，我们评估了14个生长和形态特征低和高资源条件下的42个一年生植物物种从两个源社区在以色列不同的资源可用性。正如目前的理论预测，植物生长在高资源处理较大，有两倍大的相对增长率（RGR）和薄的叶子，并分配较少的生物量比植物生长在低资源处理的根。这些特征的差异是不太一致的两个来源社区之间。相反，分类群（禾本科、豆科和一组其他杂类草），无论来源如何，在大多数特征上都存在差异。3、使用对所有14个性状的聚类分析，在两种资源处理中确定了三个一般物种群（功能群）。在这两个资源处理单子叶植物几乎完全分离成一个不同的集群，无论源栖息地，而其他两个，主要是双子叶植物，集群部分分开的栖息地。然而，双子叶植物集群的物种组成和性状特征的处理之间的差异很大。在低资源条件下，两个双子叶植物类群通过大小性状和种子质量分离，而在高资源条件下，两个类群通过地上部分大小、形态和RGR分离.主成分分析表明，处理之间的性状和物种群之间的关系不一致。前两个主要组成部分强调不同方面的增长取决于治疗，第三个轴是由增长率定义。与聚类分析一样，物种得分图显示物种按生境的分离相对较小。5，每个物种的反应因不同性状和生长条件而异。在不同的实验条件下，不同的官能团中的物种之间的变异可能不同，从而产生不同的官能团定义。由于大多数功能群分析是在收集数据的基础上进行的，而没有对生长条件进行操纵，因此关于物种或群落对环境条件变化的反应的结论可能是有问题的。
1. Plant functional groups are used to describe patterns of community organization. However, they are defined either by suites of correlated traits or by species groupings, and the responses of these two definitions to changing environmental conditions are unknown.2, We assessed 14 growth and morphological traits under low- and high-resource conditions of 42 annual plant species from two source communities in Israel that differed in resource availability. As current theory predicts, plants growing in the high-resource treatment were larger, had twofold greater relative growth rate (RGR) and thinner leaves, and allocated less biomass to roots than plants grown in the low-resource treatment. Differences in these traits were less consistent between the two source communities. Instead, taxonomic groups (grasses, legumes and a group of other forbs), regardless of source, differed in most characteristics.3, Three general groups of species (functional groups) were identified in both resource treatments using cluster analysis on ail 14 traits. In both resource treatments monocots were almost completely separated into one distinct cluster, regardless of source habitat, while the two other, mainly dicot, clusters were partially separated by habitat. However, the species composition and trait characterization of the dicot clusters differed strongly between treatments. Under low-resource conditions the two dicot clusters were separated by size traits and seed mass, but under high-resource conditions, they were separated by above-ground size, morphology and RGR.4. Principal components analysis demonstrated inconsistency in relationships among traits and species groupings between treatments. The first two principal components emphasized different aspects of growth depending on the treatment; the third axis was defined by growth rates. As with the cluster analysis, plots of species scores revealed relatively little separation of species by habitat.5, The response of each species varies for different traits and with growing conditions. Variation may differ among species within a functional group, producing different definitions of functional groups under different experimental conditions. Because most functional group analyses are performed on data collected without manipulation of growing conditions, conclusions concerning the response of species or communities to changes in environmental conditions may be problematic.