Ecosystem models, such as Ecopath with Ecosim (EwE), provide a platform to simulate intricate policy scenarios where multiple species, pressures, and ecosystem services interact. Complex questions often return complex answers, necessitating evidence and advice to be communicated in terms of trade-offs, risks, and uncertainty. Calibration procedures for EwE, which can act as a source of uncertainty and bias in model results, have yet to be explored in a comprehensive way that communicates how sensitive model outputs are to different calibration approaches. As the EwE community has grown, multiple divergent approaches have been applied to calibrate models through the estimation of vulnerability multipliers: parameters that augment the consumption rate limits of predators. Here we explore the underlying principles of vulnerability multipliers as well as existing calibration approaches and their justification. Two case studies are presented: the first explores how vulnerability multipliers emerge based on the chosen calibration approach using simulated data, while the second takes two operational EwE models (Irish Sea and Northwest Atlantic Continental Shelf) and compares their outputs when calibrated following alternate calibration approaches. We show how calibration approaches can impact model-derived advice and provide a list of best practice recommendations for EwE calibration.

中文翻译：

---

校准生态系统模型以支持基于生态系统的海洋系统管理

生态系统模型，例如 Ecopath with Ecosim (EwE)，提供了一个平台来模拟多种物种、压力和生态系统服务相互作用的复杂政策场景。复杂的问题通常会带来复杂的答案，需要在权衡、风险和不确定性方面传达证据和建议。EwE 的校准程序可能成为模型结果的不确定性和偏差的来源，尚未以全面的方式进行探索，以传达模型输出对不同校准方法的敏感程度。随着 EwE 社区的发展，多种不同的方法已被应用于通过估计脆弱性乘数来校准模型：这些参数可以增加捕食者的消耗率限制。在这里，我们探讨了漏洞乘数的基本原理以及现有的校准方法及其理由。介绍了两个案例研究：第一个案例探讨了脆弱性乘数如何根据所选择的校准方法使用模拟数据出现，而第二个案例则采用两个可操作的 EwE 模型（爱尔兰海和西北大西洋大陆架），并比较按照替代校准方法进行校准时的输出。我们展示了校准方法如何影响模型得出的建议，并提供 EwE 校准的最佳实践建议列表。