Oxygen dynamics in shelf seas sediments incorporating seasonal variability.
Oxygen dynamics in shelf seas sediments incorporating seasonal variability.
复制标题
考虑季节变化的陆架海沉积物中的氧动态。
DOI：
10.1007/s10533-017-0326-9
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发表时间：
2017
期刊：
影响因子：
4
通讯作者：
Hicks N
中科院分区：
文献类型：
--
作者：
Hicks N
陆架沉积物在全球地球化学循环中起着至关重要的作用，是氧气消耗和碳矿化的特别重要区域。底栖生物总摄氧量，即扩散和动物介导的摄氧量的总和，是量化碳矿化的一个强有力的替代指标。然而，氧的吸收率是动态的，由于沉积物内的成岩过程，可以是空间和时间可变的。在凯尔特海，包括梯度的粘性渗透性沉积物的四个底栖网站，取样超过四个航次，以捕捉氧气动态的季节和空间变化。通过一套孵化实验测量总摄氧率，并在所有四个底栖地点采用氧微电极剖面，以提供氧渗透深度和扩散摄氧率。TOU和DOU之间的差异允许动物介导的氧摄取和扩散摄取的量化。高分辨率的测量结果显示出明确的季节和空间趋势，较高的摄氧率测量粘性沉积物相比，渗透性沉积物。沉积物类型之间的氧动力学的显着差异是一致的季节之间，增加耗氧量期间和之后的浮游植物水华。陆架沉积物中的碳矿化受沉积物类型和季节性的强烈影响。
Shelf sediments play a vital role in global biogeochemical cycling and are particularly important areas of oxygen consumption and carbon mineralisation. Total benthic oxygen uptake, the sum of diffusive and faunal mediated uptake, is a robust proxy to quantify carbon mineralisation. However, oxygen uptake rates are dynamic, due to the diagenetic processes within the sediment, and can be spatially and temporally variable. Four benthic sites in the Celtic Sea, encompassing gradients of cohesive to permeable sediments, were sampled over four cruises to capture seasonal and spatial changes in oxygen dynamics. Total oxygen uptake (TOU) rates were measured through a suite of incubation experiments and oxygen microelectrode profiles were taken across all four benthic sites to provide the oxygen penetration depth and diffusive oxygen uptake (DOU) rates. The difference between TOU and DOU allowed for quantification of the fauna mediated oxygen uptake and diffusive uptake. High resolution measurements showed clear seasonal and spatial trends, with higher oxygen uptake rates measured in cohesive sediments compared to the permeable sediment. The significant differences in oxygen dynamics between the sediment types were consistent between seasons, with increasing oxygen consumption during and after the phytoplankton bloom. Carbon mineralisation in shelf sediments is strongly influenced by sediment type and seasonality.