An adaptive food web model for the epipelagic and mesopelagic

这是为了解海洋生物群的碳循环而进行的建模和综合工作的继续。 该项目的智力价值在于开发一个微生物食物网模型，在该模型中，选择不受约束的参数值以产生具有特定弹性程度的稳定状态，这意味着系统在特征时间常数小于特定值的小扰动后恢复平衡。 这是一种与大多数建模练习非常不同的方法，在大多数建模练习中，通过最小二乘法选择参数值，以提供与现场数据的最佳拟合。 在先前的研究中，假设系统稳定下来，进入具有最大弹性的稳定状态，这意味着恢复平衡比任何其他稳定状态都要快。 然而，进一步的考虑表明，系统的有趣特性（例如，输出比、官能团组成）受到很好的约束，而不要求系统处于绝对最有弹性的状态。 如果与恢复平衡有关的时间常数小于10-20天，则系统特性被明确定义。 使用新的稳定性标准，将探讨对现有模型的修改如下：（1）可能简化食物网模型，以便于将其纳入物理循环模型，（2）开发该模型的光限制版本，（3）开发一个类似模型，以描述中层的微生物过程，（4）利用中层模式探讨水平平流和扩散过程在有机质矿化和耗氧中的重要性。拟议工作的更广泛影响包括：（1）培训一名研究生;（2）将工作成果纳入主要调查员教授的研究生课程（海洋学家数学方法）;（3）将工作中的概念和经验教训纳入夏威夷大学针对少数民族本科生的课程。 第三个影响反映了主要研究员在题为“夏威夷Kumu-Ola：知识来源方案”的赠款中的作用，该方案由国家科学基金会人力资源开发部部落学院和大学方案资助。 该补助金旨在吸引来自少数群体的学生，特别是夏威夷和太平洋岛屿血统的学生，从事科学，技术，工程和数学（STEM）的职业。 吸引少数民族进入STEM并在他们入学后留住他们的关键之一是使材料具有文化相关性。 将简单的数学原理应用于海洋食物网和渔业管理是使这些学生对数学感兴趣的好方法。 PI在Kumu-Ola项目上的持续工作将使他能够将这项研究的结果纳入夏威夷少数民族学生的文化相关课程。

This is a continuation of modeling and synthesis efforts to understand carbon cycling by the ocean biota. The intellectual merit of the project lies in the development of a microbial food web model in which otherwise unconstrained parameter values are chosen to produce a steady state having a specified degree of resiliency, meaning that the system returns to equilibrium following a small perturbation with a characteristic time constant less than a specified value. This is a very different approach from most modeling exercises in which parameter values are chosen by least squares to give the best possible fit to field data. In the prior study, it was assumed that the system settled down into a steady state with maximum resiliency, meaning that the return to equilibrium was more rapid than any other steady state. Further consideration has indicated, however, that the interesting characteristics of the system (e.g., export ratio, composition in terms of functional groups) are well constrained without requiring that the system be in the absolutely most resilient state. If the time constant associated with return to equilibrium is less than 10-20 days, system characteristics are sharply defined. Using the new stability criterion, modifications to the existing model will be explored as follows: (1) possible simplification of the food web model to facilitate its incorporation into a physical circulation model, (2) development of a light-limited version of the model, (3) development of an analogous model to describe microbial processes within the mesopelagic, and (4) use of the mesopelagic model to explore the importance of horizontal advection and diffusion processes in the remineralization of organic matter and consumption of oxygen. The broader impacts of the proposed work include (1) the training of a graduate student, (2) incorporation of results of the work into a graduate course taught by the principal investigator (Mathematical Methods for Oceanographers), and (3) incorporation of concepts and lessons learned from the work into curricula targeting undergraduate minorities at the University of Hawaii. The third impact reflects the role of the principal investigator on a grant entitled "Hawaii Kumu-Ola: Source of Knowledge Program", which is funded by the NSF Division of Human Resources Development Tribal Colleges and Universities program. That grant is intended to draw students from minority groups, particularly those of Hawaiian and Pacific Island ancestry, into careers in science, technology, engineering, and mathematics (STEM). One of the keys to drawing minorities into STEM and to retaining them once they enroll is make the material culturally relevant. The application of simple mathematical principles to marine food webs and to fisheries management is a great way to interest these students in mathematics. The PI's continued work on the Kumu-Ola project will allow him to integrate the results of this research into culturally relevant curricula for minority students in Hawaii.