浊流粉黏比与浓度对不同类型微塑料沉积过程的影响

    Effects of grain size component and concentration of turbidity current on the deposition of different types of microplastics: An experimental study

    • 摘要: 浊流是海洋沉积物“源-汇”系统的重要组成部分,也是将沉积物向深海搬运的重要动力机制,其对深海沉积、资源与环境的影响都十分重要。由于触发机制、沉积物粒度组成以及浓度的差异,浊流也存在多种不同类型。虽然浊流作为微塑料运移的载体已被广泛认识,然而不同粉黏比的浊流对不同微塑料迁移与沉积的影响尚不明确。本研究通过室内试验,配制不同粉黏比的浊流,探究其所携带不同种类微塑料的沉积过程。研究结果表明,浊流浓度与黏土比例的升高将显著增强其向下游搬运微塑料的能力,且微塑料迁移受材质与形态双重影响,高密度微塑料的搬运距离普遍大于低密度微塑料,颗粒状微塑料易在上游沉积,而碎片与纤维状微塑料的搬运距离更远。

       

      Abstract: Submarine turbidity currents are an important part of the marine sediment source-sink system and a substantial driving force for transporting sediment into the deep sea, posing extensive impacts on deep-sea sedimentation, resources, and the environment. Different types of turbidity currents arise from variations in triggering mechanisms, grain size component, and concentration. Although turbidity currents are widely recognized as carriers of microplastic transport, the effects of turbidity currents with different silt/clay ratios on the migration and deposition of various microplastics remain unclear. Indoor flume experiments were conducted to simulate the deposition of different microplastics carried by turbidity currents. Results show that turbidity current in high concentration with rich clay content could significantly enhance the downstream transport ability of microplastics, which was influenced by the material and shape of microplastics. Higher-density microplastics were generally transported farther than low-density ones, whereas granular microplastics tended to deposit upstream, while fragmentary and fibrous microplastics were carried over longer distances.

       

    /

    返回文章
    返回