PREDICTION OF COASTAL SEDIMENT STABILITY FROM PHOTOPIGMENT CONTENT OF MATS OF PURPLE SULFUR BACTERIA
PREDICTION OF COASTAL SEDIMENT STABILITY FROM PHOTOPIGMENT CONTENT OF MATS OF PURPLE SULFUR BACTERIA
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DOI：
10.1038/330244a0
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发表时间：
1987-11-19
期刊：
影响因子：
64.8
通讯作者：
GUST, G
中科院分区：
文献类型：
--
作者：
GRANT, J;GUST, G
水流和波浪对沉积物侵蚀的阈值（临界摩擦速度）是沉积学和海岸工程中的重要预测工具1，2，因为它用于夹带和运输速率方程。泥沙输运的测量与许多问题有关，包括污染物和疏浚弃土的扩散、港口和海滩的稳定性、地球化学通量和动物-泥沙关系3。在海洋沉积物中，生物过程改变了侵蚀标准4，例如通过硅藻、细菌和其他底栖生物的细胞外产物结合和稳定沉积物表面5、6。尽管底栖微生物垫和随之而来的沉积物结合广泛存在，但对自然海洋沉积物的侵蚀阈值和迁移率的预测仅定性地纳入了生物变量5，7。我们使用实验室水槽侵蚀完整的沉积物芯含有未受干扰垫的光合紫硫细菌。细菌膜（细菌叶绿素）的色素含量呈正相关，与无菌对照核心相比，增加侵蚀阈值高达五倍。我们展示了海底微生物对海洋沉积物侵蚀预测的深远影响。
The threshold of sediment erosion by currents and waves (critical friction velocity,) is an important predictive tool in sedimentology and coastal engineering1,2owing to its use in entrainment and transport rate equations. The measurement of sediment transport is relevant to many concerns including dispersal of pollutants and dredge spoil, harbour and beach maintainence, geochemical fluxes and animal–sediment relations3. In marine sediments, biotic processes alter erosion criteria4, for instance through binding and stabilization of the sediment surface by the extracellular products of diatoms, bacteria and other benthic organisms5,6. Despite the widespread occurrence of benthic microbial mats and attendant sediment binding, prediction of erosion thresholds and transport rates in natural marine sediments has incorporated biotic variables only qualitatively5,7. We used a laboratory flume to erode intact sediment cores containing undisturbed mats of phototrophic purple sulphur bacteria. The pigment content of bacterial films (bacterio-chlorophylla) was positively correlated with, increasing the erosion threshold as much as fivefold compared with sterile control cores. We demonstrate the profound influence of benthic micro-biota on prediction of erosion in marine sediments.