Modeling Microbial Biogeochemistry in Permeable Reactive Barriers

CBET- 0756562Vallino，约瑟夫海洋生物学实验室模拟可渗透反应屏障中的微生物生物地球化学拟议工作的主要目的是证明最大熵产生原理是理解微生物生物地球化学的坚实基础。这项工作解决了更好地了解代谢网络的需要，即分布在不同微生物物种之间但高度协调的代谢途径。为了开发稳健的生物地球化学模型，需要更好地了解控制分布式微生物代谢网络的组织和功能的机制。现有的微生物生物地球化学模型是还原论的，并遵循竞争排斥原则，即生长最快的物种将占据主导地位。然而，在微生物群落中观察到的共养和合作无法用这一原理来解释。非平衡热力学可能提供更普遍的理论来解释此类观察结果。该提案旨在开发一种基于最大能量生产（MEP）原理（复杂性理论领域的原理）的生物地球化学模型。 MEP 理论指出，具有多个自由度的复杂系统将组织到最大熵产生的状态。这项工作将为描述微生物生物地球化学带来新的理论进展。该方法的创新之处在于它试图扩展复杂性理论来描述微生物群落的功能。这是很有价值的，因为现有的还原论模型在鲁棒性和预测能力方面都失败了。该模型的一个优点是新理论将使用 PRB 现场进行测试。研究者写了一份扎实的提案，写得很好，全面涵盖了适当的文献，并且在细节和广度之间取得了适当的平衡。通过有意义的本科研究和教育经历可以实现更广泛的影响。

CBET- 0756562Vallino, JosephMarine Biology LaboratoryModeling Microbial Biogeochemistry in Permeable Reactive BarriersThe primary objective of the proposed work is to demonstrate that the maximum entropy production principle is a solid foundation for understanding microbial biogeochemistry. This work addresses the need to have a better understanding of metabolic networks -- that is, metabolic pathways distributed across different microbial species, yet highly coordinated. In order to develop robust models of biogeochemistry, better understanding of the mechanisms that govern organization and function of distributed microbial metabolic networks is needed. Existing models of microbial biogeochemistry are reductionist, and adhere to the competitive exclusion principle which states that the species that grows the fastest will dominate. However, there are observations of syntrophy and cooperation in microbial communities that cannot be explained by this principle. Non-equilibrium thermodynamics may provide a more universal theory to explain such observations. This proposal seeks to develop a biogeochemical model based on the principles of maximum energy production (MEP), a principle in the realm of complexity theory. The MEP theory states that complex systems with many degrees of freedom will organize to a state of maximum entropy production. This work will lead to new theoretical advancements to describe microbial biogeochemistry. The approach is innovative in that it seeks to extend complexity theory to describe microbial community functioning. This is valuable because existing reductionist models fail in robustness and predictive power. A strength of the model is that the new theory will be tested using a field site for PRB. The investigator has written a solid proposal it is well written, comprehensive in coverage of appropriate literature, and has the right balance of detail and breadth. Broader impacts are achieved through meaningful undergraduate research and educational experiences.