WAMSI 2 - Dredging Node - Theme 3 - Synthesis Report - Characterisation and prediction of dredge-generated sediment plume dynamics and fate.

Dredge plume modelling is often used in Environmental Impact Assessment (EIA) of large-scale port and coastal developments to quantify and model the transport and fate of sediments released during dredging operations. The objectives of the WAMSI Dredging Science Node (DSN) Theme 3 was to provide insights and guidance on ways to improve the modelling and monitoring of passive dredging plumes to support the EIA and management of dredging programs, with a focus on the Pilbara region of Western Australia. By carefully designing a number of laboratory, field and numerical model investigations, Theme 3 advanced the modelling and measurement (via remote sensing) of dredging generated plumes. Under an agreement with WAMSI, unprecedented access was granted to baseline, dredging and monitoring data from a major dredging project in the Pilbara region. Effort focused on modelling the dynamics and fate of total suspended solids (TSS) in the passive dredging plume, with the goal of identifying the most important processes and model parameters.Those processes included in-canopy sediment transport processes, the bed schematization and cohesive sediment transport model parameters. The utility of applying remote sensing techniques to monitor sediment plumes and establishing background conditions was also explored. Importantly, the research program was undertaken to ensure the model output parameters and their representations and analyses, were compatible with the critical effects thresholds (e.g. 14 day running percentiles, daily light integral) that were being generated by the biological themes of the WAMSI DSN (see Themes 4 to 7).

疏浚羽流模拟常应用于大型港口与沿海开发项目的环境影响评价（Environmental Impact Assessment, EIA），用于量化并模拟疏浚作业中释放沉积物的运移与归宿。WAMSI疏浚科学节点（DSN）主题3的目标，是为改进被动疏浚羽流的模拟与监测方法提供见解与指导，以支撑疏浚项目的环境影响评价与管理工作，研究重点聚焦于澳大利亚西部的皮尔巴拉地区。通过精心设计一系列实验室、现场及数值模型研究，该主题推动了疏浚产生羽流的模拟与（依托遥感手段开展的）监测工作发展。根据与WAMSI达成的协议，研究团队获得了皮尔巴拉地区某大型疏浚项目的基线数据、疏浚作业数据及监测数据，此类数据获取权限前所未有。研究核心聚焦于模拟被动疏浚羽流中总悬浮颗粒物（Total Suspended Solids, TSS）的动力学过程与归宿，旨在明确核心影响过程与模型参数。所涉及的过程包括冠层内沉积物运移过程、床体概化及黏性沉积物运移模型参数。研究同时探索了应用遥感技术监测沉积物羽流并建立背景基准条件的实用性。尤为关键的是，本研究项目的开展旨在确保模型输出参数及其表征与分析结果，能够与WAMSI疏浚科学节点生物主题（详见主题4至7）所生成的关键效应阈值（如14日滑动百分位数、日光积分）相兼容。