Substrate affects microbial driven distribution of energy and matter among organic carbon functional pools in soil - Driver Pool

基质影响土壤中有机碳功能池中微生物驱动的能量和物质分布 - 驱动池

• 批准号: 465122757
• 负责人: Privatdozent Dr. Thomas Maskow
• 金额: --
• 依托单位: Universitätsleitung - Präsidium
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/465122757?language=en
• 关键词: Substrate; affects; microbial; driven; distribution

Microbial transformation of organic matter (OM) is a necessity for long-term storage of SOM. Thereby, microorganisms metabolize OM through enzymatic activity, converting it into own biomass or respiring it for energy consumption. This results in a flux of energy and matter that is modulated and retarded by continuous recycling of matter and residual energy. The carbon use efficiency (CUE) of transformation depends on the properties of the various substrates (quality of provided energy), on the microbial metabolism, the connectivity within the microbiome, and environmental factors. In order to model that complex, combined turnover of matter and energy a more generalized conception is required. This asks for a thermodynamic-based approach describing transformations and interactions on the level of OC turnover and distribution among different functional pools in soil. Additionally, process kinetics (rates) must be considered because the optimum trade-off between efficiency and rate marks the process optimum.Hence, the overall aim of the project Driver Pool is to understand the interplay between energy fluxes/thermodynamic balances and substrate turnover pathways, modulated by shifts in microbial abundance, community structure and functioning. Which are the most relevant thermodynamic driving forces directing OC transformation processes and distribution among OM functional pools in soil? We hypothesize that OM turnover is driven by an energy flux-controlled interplay between three process types varying in their rate, energy balance and tendency to dissipate, keep or accumulate Gibbs energy. Furthermore, OC from substrates may be distributed among various functional pools in soil that can be energetically distinguished in “enthalpy storage pools” representing ordered structures like biomass and “(temporary) entropy storage pools” like supramolecular OM and necromass.The project is part of a group of coordinated core-projects. Joint microcosm incubation experiments were planned that are coordinated between the three PIs. The turnover of seven substrates, mostly with well-defined molecular and thermodynamic properties, added to soil will be tested in five experiments going across four work packages that are assigned to the three PIs. We aim to determine (i) complete balances of energy and matter for microbial turnover, (ii) kinetics of microbial driven processes and (iii) quantities of the distribution of substrates among soil functional pools, in order (iv) to find out which substrate properties direct fluxes of energy and matter into which pools, resulting in substrate specific CUE, EUE, and heat flow respectively. Finally, (v) a balance-based thermokinetic model will be developed integrating the combined data of WP 1-3. This model will be based on the law of Hess representing the connection between material and energy fluxes (formulated for enthalpy, entropy, Gibbs energy).

微生物对有机质的转化是有机质长期储存的必要条件。因此，微生物通过酶活性代谢OM，将其转化为自身的生物质或将其呼吸用于能量消耗。这导致能量和物质的流动，通过物质和剩余能量的连续循环来调节和延迟。转化的碳利用效率（CUE）取决于各种底物的性质（所提供能量的质量）、微生物代谢、微生物组内的连通性和环境因素。为了模拟物质和能量的复杂组合周转，需要一个更广义的概念。这要求一个基于土壤有机碳的方法来描述转换和相互作用的水平上的有机碳周转和分布在不同的功能池土壤。此外，必须考虑过程动力学（速率），因为效率和速率之间的最佳权衡标志着过程的最佳化。因此，该项目的总体目标是了解能量通量/热力学平衡和底物周转途径之间的相互作用，通过微生物丰度，群落结构和功能的变化进行调节。土壤有机质功能库中有机质转化和分配的热力学驱动力是什么？我们假设，OM营业额是由三种过程类型之间的能量通量控制的相互作用，它们的速率，能量平衡和耗散，保持或积累吉布斯能的趋势不同。此外，OC从基板可以分布在土壤中的各种功能池，可以大力区分在“焓存储池”代表有序的结构，如生物量和“（临时）熵存储池”，如超分子OM和necromass.The项目是一组协调的核心项目的一部分。计划在三个主要研究者之间协调进行联合微观世界孵化实验。营业额的七个基板，大多具有明确的分子和热力学性质，添加到土壤中，将在五个实验中进行测试，跨越四个工作包，分配给三个PI。我们的目标是确定（i）完全平衡的能量和物质的微生物周转，（ii）动力学的微生物驱动的过程和（iii）数量的基质之间的土壤功能池的分布，以（iv）找出哪些基板属性的直接通量的能量和物质进入哪些池，从而导致基板特定的CUE，埃厄，和热流分别。最后，（v）将结合WP 1-3的综合数据开发基于平衡的热动力学模型。该模型将基于赫斯定律，该定律代表物质和能量通量之间的联系（针对焓、熵、吉布斯能制定）。