Many autotrophs vary their allocation to nutrient uptake in response to environmental cues, yet the dynamics of this plasticity are largely unknown. Plasticity dynamics affect the extent of single versus multiple nutrient limitation and thus have implications for plant ecology and biogeochemical cycling. Here we use a model of two essential nutrients cycling through autotrophs and the environment to determine conditions under which different plastic or fixed nutrient uptake strategies are adaptive. Our model includes environment-independent costs of being plastic, environment-dependent costs proportional to the rate of plastic change, and costs of being mismatched to the environment, the last of which is experienced by both fixed and plastic types. In equilibrium environments, environment-independent costs of being plastic select for tortoise strategies—fixed or less plastic types—provided that they are sufficiently close to co-limitation. At intermediate levels of environmental fluctuation forced by periodic nutrient inputs, more hare-like plastic strategies prevail because they remain near co-limitation. However, the fastest is not necessarily the best. The most adaptive strategy is an intermediate level of plasticity that keeps pace with environmental fluctuations, but is not faster. At high levels of environmental fluctuation, the environment-dependent cost of changing rapidly to keep pace with the environment becomes prohibitive and tortoise strategies again dominate. The existence and location of these thresholds depend on plasticity costs and rate, which are largely unknown empirically. These results suggest that the expectations for single nutrient limitation versus co-limitation and therefore biogeochemical cycling and autotroph community dynamics depend on environmental heterogeneity and plasticity costs.

中文翻译：

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养分吸收策略的动态变化：乌龟和野兔的教训。

许多自养生物根据环境提示而改变其对养分吸收的分配，但是这种可塑性的动力学很大程度上未知。可塑性动力学影响单一和多种养分限制的程度，因此对植物生态学和生物地球化学循环具有影响。在这里，我们使用两种通过自养生物和环境循环的基本营养素模型来确定不同塑料或固定营养素吸收策略适应性的条件。我们的模型包括与环境无关的塑料成本，与塑料变化率成比例的与环境相关的成本以及与环境不匹配的成本，其中固定成本和塑料类型都经历了最后一次。在平衡环境中 选择与环境无关的费用作为乌龟策略的塑料（固定的或较少的塑料类型），前提是它们足够接近共同限制。在周期性的养分投入迫使环境波动达到中等水平时，更多的像野兔一样的塑性策略盛行，因为它们仍处于共同限制之下。但是，最快不一定是最好的。最具适应性的策略是可塑性的中间水平，可以与环境波动保持同步，但速度不会更快。在高水平的环境波动下，与环境保持同步而迅速变化的与环境有关的成本变得过高，乌龟策略再次占主导地位。这些阈值的存在和位置取决于可塑性成本和可塑性，在经验上很大程度上未知。