Fundamental Predictability in Multispecies Competition: The Influence of Large Disturbance
Fundamental Predictability in Multispecies Competition: The Influence of Large Disturbance
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多物种竞争的基本可预测性：大干扰的影响
DOI：
10.1086/378750
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发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Yesim Buyukates
中科院分区：
文献类型：
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作者：
D. Roelke;Sarah Augustine;Yesim Buyukates
生态系统中混沌或复杂行为的经验证据很少，大概是由于系统级噪声较高和/或复杂行为发生所需条件的稀有。另一种解释可能是，复杂的行为是脆弱的，很容易受到许多生态系统中常见的干扰的抑制。在这里，我们研究了干扰频率和强度对复杂行为的作用，并重点关注浮游生物系统中的种群演替轨迹。由于其在水生生态学中的突出地位，我们使用水力冲洗和营养物加载作为干扰。我们使用天然浮游生物组合进行的数值模拟练习和实验室微观实验的结果表明，当水力冲洗和营养物负荷的幅度和周期性较大时，复杂行为的一个方面，即附近轨迹的发散，会受到抑制。换句话说，复杂的继承变得可以确定。然而，附近轨迹的发散相对较强，因为需要不少于总流入量 85% 的脉冲来抑制这种行为。我们的数值研究结果还表明，大的水力扰动可能会给系统带来复杂行为的另一个方面，即非周期性演替。
Empirical evidence of chaos, or complex behavior, in ecosystems is scarce, presumably due to high system‐level noise and/or the rarity of conditions necessary for complex behavior to arise. An alternative explanation might be that complex behavior is fragile and readily suppressed by disturbances that are common in many ecosystems. Here we investigated the role of disturbance frequency and magnitude on complex behavior and focused on population succession trajectories in a plankton system. Because of its prominence in aquatic ecology, we used hydraulic flushing and nutrient loading as disturbances. Our findings from numerical modeling exercises and laboratory microcosm experiments using natural plankton assemblages indicated that one aspect of complex behavior, divergence of nearby trajectories, was suppressed when the magnitude and periodicity of hydraulic flushing and nutrient loading were large. In other words, complex succession became determinable. Divergence of nearby trajectories was relatively robust, however, because pulses of not less than 85% of the total inflow were required to suppress this behavior. Our numerical findings also revealed that large hydraulic disturbances could introduce to the system another aspect of complex behavior, aperiodic succession.