电流在海洋沉积物中的空间分离的生物地球化学过程中起作用
Lars Peter Nielsen1, Nils Risgaard-Petersen, Henrik Fossing
1Department of Biological Sciences, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark. biolpn@biology.au.dk
Nature
|February 26, 2010
概括
沉积物中的电流将表面氧气使用与深层硫和碳氧化联系起来. 这种微生物电气通信揭示了大自然中新的生物地球化学过程.
科学领域:
- 微生物生态学 微生物生态学
- 生物地质化学生物地质化学
- 环境科学 环境科学
背景情况:
- 细菌可以进行细胞外电子转移 (EET) 进行营养循环.
- 没有证据表明EET将微米尺度以外的生物地质化学过程结合起来.
研究的目的:
- 为了调查电流是否在自然环境中将空间分离的生物地质化学过程结合起来.
- 为了证明微生物在深层沉积物中的电通信.
主要方法:
- 在不同覆盖氧气度下研究了脱沉积物.
- 测量了沉积物中的硫化和pH值变化.
- 执行了氧气消耗的质量平衡计算.
主要成果:
- 电流迅速将表面的氧气消耗与深层硫化物和有机碳氧化联系起来.
- 超过40%的沉积物总氧气消耗是由导导电子驱动的.
- 在氧区观察到明显的pH峰值,表明电化学过程.
结论:
- 由微生物纳米线和其他组件传导的电流将沉积物中遥远的生物地球化学过程结合起来.
- 这种电气通信扩大了对微生物生态学和生物地球化学循环的理解.
相关概念视频
Marine Microbial Ecology
Marine microbial ecosystems are shaped by distinct physicochemical limits, including high salinity, low nutrient availability, and fluctuating oxygen levels. These conditions favor smaller microbial cell sizes, which maximize their surface-to-volume ratio for efficient nutrient uptake.Microbial activity and community composition are closely linked to biogeochemical cycles, particularly in dynamic environments like estuaries, where halotolerant microbes thrive in response to variable salinity...
Microbial Mats
Microbial communities forming biofilms and mats represent complex, spatially structured ecosystems where metabolic processes are stratified according to light, oxygen, and nutrient gradients. Biofilms are initial colonization stages, only a few millimeters thick, while mature microbial mats can reach centimeter-scale thickness and display intricate vertical organization. Their structural and functional heterogeneity allows microorganisms to occupy distinct ecological niches within a few...
Deep Sea Microbial Ecology
The deep ocean and its underlying sediments represent vast, largely unexplored microbial habitats that extend far beyond the sunlit photic zone. The photic (euphotic) zone typically spans the upper ~100–200 meters of pelagic waters in the open ocean, but its depth varies geographically and seasonally, where sufficient light supports photosynthetic life. Below this lies the deep sea, spanning roughly 1000–6000 meters (bathypelagic to abyssal zones), with deeper hadal trenches extending beyond...
What are Biogeochemical Cycles?
The most common elements in organic molecules, carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus, are only available in the ecosystem in limited amounts. Therefore, these nutrients must be recycled through both biotic and abiotic components of the ecosystem, in processes generally called biogeochemical cycles.
Processes at Electrodes
The electrode interacts with ions in the electrolyte solution at its interface. The rate of oxidation and reduction depends on the speed at which electrons can transfer through this interface. As ions attach to or leave the electrode surface, the electrode acquires a charge, and an electrical potential forms across the interface, making the process more difficult to reach equilibrium. The charge on the electrode affects the local ion concentrations in the solution, though thermal motion...
Freshwater Microbial Ecology
Freshwater systems such as streams, rivers, and lakes exhibit distinct physical and biological characteristics that influence their microbial communities. These environments are broadly categorized into lotic systems—those with flowing waters like streams and most rivers—and lentic systems, which include still or slow-moving waters such as lakes, ponds, and marshes.In lentic systems, phytoplankton drive primary production, generating autochthonous organic carbon. In contrast, lotic systems...


