Dispersal-Dormancy Relationships in Annual Plants: Putting Model Predictions to the Test
Dispersal-Dormancy Relationships in Annual Plants: Putting Model Predictions to the Test
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一年生植物的扩散-休眠关系：将模型预测付诸测试
DOI：
10.1086/656271
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
K. Tielbörger
中科院分区：
文献类型：
--
作者：
W. Siewert;K. Tielbörger
赌注对冲是一种在空间和时间上不可预测的环境中增加适应性的手段。在这样的环境中，模型预测的赌注对冲策略之间的权衡扩散和休眠，而减少风险的可预测性下降的重要性日益增加，应导致扩散和休眠沿着梯度的环境可预测性增加。然而，到目前为止，还没有实验研究来验证这些预测。在这里，我们使用了一组新的田间实验，使我们能够量化和分离的幼苗招聘从三个来源：本地繁殖，休眠和扩散。这项研究包括了来自五个环境的整个植物群落，这些环境在可预测性上有很大的不同。环境中的扩散和休眠之间存在着一种权衡关系，而且在不可预测的环境中的使用越来越多，但这方面的证据非常薄弱。在我们的系统中的人口和社区动态的扩散的重要性是非常低的休眠和本地繁殖。这表明，与其他降低风险的战略相比，分散对缓冲环境变化的作用可以忽略不计。我们的研究结果强调了迫切需要多物种和多地点的实验在理论预测的实证检验。
Bet hedging is a means to increase fitness in environments that vary unpredictably in space and time. In such environments, models predict a trade-off between the bet-hedging strategies dispersal and dormancy, while the increasing importance of risk reduction with decreasing predictability should lead to an increase in dispersal and dormancy along gradients of environmental predictability. However, so far there has been no experimental study to test these predictions in the field. Here, we used a set of novel field experiments that enabled us to quantify and separate seedling recruitment from three sources: local reproduction, dormancy, and dispersal. The study included the entire plant community from five environments differing considerably in predictability. Evidence for both the existence of a trade-off between dispersal and dormancy within environments and their increased use in unpredictable environments was very weak. The importance of dispersal for population and community dynamics in our system was extremely low relative to dormancy and local reproduction. This indicates that the role of dispersal for buffering environmental variation may be negligible compared with other risk-reducing strategies. Our findings highlight the urgent need for multispecies and multisite experiments in empirical tests of theoretical predictions.