Internal tide — shelf topography interactions as a forcing factor governing the large-scale distribution and burial fluxes of particulate organic matter ( POM ) in the Benguela upwelling system
Internal tide — shelf topography interactions as a forcing factor governing the large-scale distribution and burial fluxes of particulate organic matter ( POM ) in the Benguela upwelling system
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内潮-陆架地形相互作用作为控制本格拉上升流系统中颗粒有机物（POM）大规模分布和埋藏通量的强迫因素
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
E. Klingelhoefferc
中科院分区：
文献类型：
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作者：
P. J. M. Monteiroa;G. Nelsonb;A. V. D. Plasc;E. Mabillea;G. W. Baileyd;E. Klingelhoefferc
本研究调查的作用，内潮汐驱动沉积和重新悬浮的生物POM在纳米比亚大陆架上，并产生稳定的500- 800公里长的海岸交替带的高和低POM浓度。温度的时间序列数据（2000年9月至2001年3月），从海底边界层在三个站点被用来假设，占主导地位的强迫机制是内部潮汐和他们的相互作用与货架断裂带。温度结构的垂直位移100- 150米，在外部大陆架休息（深度450米）显示发生在整个6个月的时间序列。与此相反，在非陆架断裂点，温度的垂直位移可以忽略不计。由温度结构的100- 150 m垂直位移预测的陆架坡折带向陆方向的剪应力（40.1Pa）明显高于控制生物颗粒和细颗粒沉积物再悬浮的临界剪应力（0.05-0.1Pa）。短期ADCP数据显示，在不同的POM地区的临界剪应力分布是一致的预测净积累和净侵蚀区的POM整个纳米比亚大陆架。这项研究假设，正压-斜压潮汐耦合支配垂直粒子通量动态，而埃克曼和惯性流被认为是支配水平平流尺度，导致所观察到的POM分布。这一改进的动态理解的重要性对碳埋藏效率以及底栖渔业生境的适宜性的可变性都有影响。r 2005 Elsevier Ltd.保留所有权利。
This study investigates the role of internal tides in driving the sedimentation and re-suspension of biogenic POM on the Namibian shelf and give rise to stable 500–800km long shore alternating bands of high and low POM concentrations. Temperature time series data (September 2000–March 2001) from the benthic boundary layer at three sites are used to hypothesise that the dominant forcing mechanism are internal tides and their interaction with the shelf break zones. Vertical displacements of the temperature structure by 100–150m at the outer shelf break (depth 450m) are shown to occur through out the 6-month time series. In contrast at non-shelf break sites the vertical displacements of temperature are negligible. The shear–stresses predicted landward of the shelf break zone from 100–150m vertical displacements of the temperature structure are significantly higher (40.1Pa) than the critical shear–stresses which govern the re-suspension of biogenic particles and fine sediments (0.05–0.1Pa). Short-term ADCP data was used to show that critical shear–stress distribution at the different POM areas is consistent with the predicted net accumulation and net erosional zones of POM across the Namibian shelf. This study hypothesises that the barotropic–baroclinic tidal coupling governs vertical particle flux dynamics whereas Ekman and inertial flows are thought to govern the horizontal advection scales that result in the observed POM distribution. The importance of this improved dynamical understanding has implications for both carbon burial efficiency as well as the variability in the suitability of benthic fisheries habitats. r 2005 Elsevier Ltd. All rights reserved.