Internal wave-induced redox shifts affect biogeochemistry and microbial activity in sediments: a simulation experiment
Internal wave-induced redox shifts affect biogeochemistry and microbial activity in sediments: a simulation experiment
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内波引起的氧化还原位移影响沉积物中的生物地球化学和微生物活动：模拟实验
DOI：
10.1007/s10533-012-9769-1
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发表时间：
2012
期刊：
影响因子：
4
通讯作者：
Grossart
中科院分区：
文献类型：
--
作者：
Frindte;Eckert;Attermeyer;Grossart
内波（假潮）是分层湖泊的物理过程研究，但其对沉积物孔隙水化学和微生物学的影响仍然在很大程度上未被探索。由于密度跃层的振荡，沉积物暴露于表湖水和表湖水之间的周期性变化。这导致了环境条件的强烈差异，这应该反映在沉积物-水界面和更深沉积层的氧化还原敏感的地球化学过程的响应中。我们测试了一系列的围隔实验的影响，seiche引起的氧化还原变化孔隙水化学和细菌活性的沉积物在良好的控制条件下。因此，我们排除了电流和温度状况变化的影响。为期10天，完整的沉积物芯从贫营养湖Stechlin进行了培养下恒定（无论是好氧或缺氧）或交替氧化还原条件。溶质浓度测定孔隙水剖面沉积物中，而微生物活性测定在上0.5厘米的沉积物。氧化和交替氧化还原条件导致类似的铵，磷酸盐，甲烷孔隙水浓度，而每种分析物的浓度是相当高的缺氧核心。微生物活性明显低于缺氧核心比在好氧和交替的核心。总之，间歇缺氧阶段长达24小时的核心没有不同的静态好氧沉积物的地球化学和微生物活动。然而，由于各种物理过程，假潮导致氧气渗透到沉积物层的更深处，这影响了沉积物的氧化还原梯度，并增加了受假潮影响的沉积物中的微生物活性。
Internal waves (seiches) are well-studied physical processes in stratified lakes, but their effects on sediment porewater chemistry and microbiology are still largely unexplored. Due to pycnocline oscillations, sediments are exposed to recurrent changes between epilimnetic and hypolimnetic water. This results in strong differences of environmental conditions, which should be reflected in the responses of redox-sensitive biogeochemical processes at both, the sediment–water interface and deeper sediment layers. We tested in a series of mesocosm experiments the influence of seiche-induced redox changes on porewater chemistry and bacterial activity in the sediments under well controlled conditions. Thereby, we excluded effects of changes in current and temperature regimes. For a period of 10 days, intact sediment cores from oligotrophic Lake Stechlin were incubated under constant (either oxic or anoxic) or alternating redox conditions. Solute concentrations were measured as porewater profiles in the sediment, while microbial activity was determined in the upper 0.5 cm of sediment. Oxic and alternating redox conditions resulted in similar ammonium, phosphate, and methane porewater concentrations, while concentrations of each analyte were considerably higher in anoxic cores. Microbial activity was clearly lower in the anoxic cores than in the oxic and the alternating cores. In conclusion, cores with intermittent anoxic phases of up to 24 hours do not differ in biogeochemistry and microbial activities from static oxic sediments. However, due to various physical processes seiches cause oxygen to penetrate deeper into sediment layers, which affects sediment redox gradients and increase microbial activity in seiche-influenced sediments.
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DOI：
--
发表时间：
1989
期刊：
影响因子：
--
作者：
D. C. Senden;D. Imboden
通讯作者：
D. Imboden
小型分层湖中的中尺度涡旋
影响因子：
2.2
作者：
G. Kirillin;C. Engelhardt;S. Golosov
通讯作者：
S. Golosov
影响因子：
4.5
作者：
COLE, JJ;PACE, ML;STEINHART, GS
通讯作者：
STEINHART, GS
缺氧低度层状湖中细菌产生的深度分布
影响因子：
4.4
作者：
R. McDonough;R. Sanders;K. Porter;D. Kirchman
通讯作者：
D. Kirchman
内水冲作用在湖上游沉积物中产生的瞬态对流
影响因子：
5.2
作者：
Kirillin;G.. C. Engelhardt;S. Golosov
通讯作者：
S. Golosov