Department of Environmental Science and Policy, University of California, Davis, Wickson Hall, 1 Shields Avenue, Davis, CA, 95616, USA.
Graduate Group in Applied Mathematics, University of California, Davis, Mathematical Sciences Building, 1 Shields Avenue, Davis, CA, 95616, USA.
Sci Rep. 2024 Mar 24;14(1):6995. doi: 10.1038/s41598-024-57108-9.
The allometric trophic network (ATN) framework for modeling population dynamics has provided numerous insights into ecosystem functioning in recent years. Herein we extend ATN modeling of the intertidal ecosystem off central Chile to include empirical data on pelagic chlorophyll-a concentration. This intertidal community requires subsidy of primary productivity to support its rich ecosystem. Previous work models this subsidy using a constant rate of phytoplankton input to the system. However, data shows pelagic subsidies exhibit highly variable, pulse-like behavior. The primary contribution of our work is incorporating this variable input into ATN modeling to simulate how this ecosystem may respond to pulses of pelagic phytoplankton. Our model results show that: (1) closely related sea snails respond differently to phytoplankton variability, which is explained by the underlying network structure of the food web; (2) increasing the rate of pelagic-intertidal mixing increases fluctuations in species' biomasses that may increase the risk of local extirpation; (3) predators are the most sensitive species to phytoplankton biomass fluctuations, putting these species at greater risk of extirpation than others. Finally, our work provides a straightforward way to incorporate empirical, time-series data into the ATN framework that will expand this powerful methodology to new applications.
近年来，用于模拟种群动态的异速营养网络（ATN）框架为了解生态系统功能提供了许多见解。在此，我们将智利中部潮间带生态系统的 ATN 模型扩展到包括浮游叶绿素-a 浓度的经验数据。这个潮间带群落需要初级生产力的补贴来维持其丰富的生态系统。以前的工作使用向系统输入浮游植物的恒定速率来模拟这种补贴。然而，数据表明，浮游动物补贴表现出高度可变的、脉冲样的行为。我们工作的主要贡献是将这种可变输入纳入 ATN 模型，以模拟这个生态系统可能对浮游植物脉冲的反应。我们的模型结果表明：（1）密切相关的海蜗牛对浮游植物的变化有不同的反应，这可以通过食物网的基础网络结构来解释；（2）增加浮游生物-潮间带混合的速度会增加物种生物量的波动，这可能会增加局部灭绝的风险；（3）捕食者是对浮游植物生物量波动最敏感的物种，与其他物种相比，这些物种灭绝的风险更大。最后，我们的工作提供了一种将经验时间序列数据纳入 ATN 框架的简单方法，这将使这种强大的方法扩展到新的应用。
