High resolution mapping of fine sediment and pollutants throughout large river cross sections with innovative uncrewed survey boats; supporting improv

利用创新型无人勘测船对整个大河流断面的细小沉积物和污染物进行高分辨率测绘；

• 批准号: 2740878
• 金额: --
• 依托单位: University of Reading
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2740878
• 关键词: resolution; mapping; fine; sediment; pollutants

All but 14% of UK rivers fail to meet the Environment Agency definition of Good Ecological Status, and none are rated good for Chemical Status1. Therefore the amount and transportation of fine sediment (sand particles and finer) and other pollutants through river systems remains of major interest to researchers and catchment stakeholders because of the fundamental importance for the process-understanding and quantification of contaminant and nutrient transfer. Sediment transport and deposition is a key to in-stream geomorphology and the resultant habitat which in turn determines biodiversity. Furthermore, knowledge of sediment fluxes is important in determining infrastructure sustainability (hydropower, flood defences), flood risk, agricultural soil loss and bathing water safety.Traditionally, the most robust fine sediment flux estimates and pollutant measurements have been from continuous bank-side monitoring or spot sampling. However, in rivers with large cross sections and/or complex and dynamic hydromorphology, fluxes will vary greatly over cross sections. Although fine particles are often assumed to be relatively evenly distributed throughout flowing cross sections the aggregation of these particles can mean that significant variations in sediment concentration can occur. Given that these variations are challenging to quantify, poorly understood and are likely to be important in the estimation of sediment and pollutant fluxes this represents a priority research area. The aim of this project is to resolve, for the first time, these cross-sectional variations in fine sediment and pollutants transport, to enable a step-change in sediment budget estimation, habitat suitability assessment, and implications for flood risk.The proposed project focusses on the use of novel instrumentation to resolve sediment and other pollutant fluxes at previously unprecedented resolution. Firstly, simultaneous, co-located measurements of river hydraulics, suspended sediment and pollutants will be obtained using advanced uncrewed survey boats. Secondly, observed variations will be investigated to elucidate cross-sectional changes in sediment/pollutants transport and their controls. Knowledge will be gained by making observations in a variety of catchment settings and across a range of flow conditions. A state of the art ADCP (Acoustic Doppler Current Profiler) instrument and multi-parameter water quality sensors will be used to make streamflow, river hydraulics, fine sediment and other pollutants measurements. The instruments will be deployed remotely using Differential GPS equipped, radio-controlled boats (ARCboat and ARCboatlite) to allow the safe survey of large and often inaccessible river and floodplain flows (see photo). The ADCP backscatter data will be evaluated against in situ physical water samples (particle size and mass) and independent direct measurements (turbidity and particle size) to provide robust calibration. This sophisticated calibration procedure is particularly well suited to a research project and will contribute to the delivery of an optimised techniques protocol. The multi-frequency ADCP sensor should allow new insights into sediment particle sizes and their spatial distribution, while the high-resolution river hydraulics data will help illustrate the settings, processes and conditions in which sediments are mobilised and deposited.Measurements undertaken with the uncrewed boats at a range of locations and times will help inform understanding of the spatial and temporal factors influencing water quality across a range of flow conditions. This will provide a more accurate quantification of downstream fluxes, enabling improved understanding of the factors and processes that control sediment and other contaminant transport, and hence chemical, biological and ecological status and bathing water safety.

除14％的英国河流外，所有河流都无法满足环境机构对良好的生态状况的定义，而没有一个对化学状态有利的。因此，由于对过程 - 污染和营养转移的过程非常重要，因此研究人员和集水区利益相关者的精细沉积物（沙粒和细胞）和其他污染物的数量和运输仍然引起了研究人员和流域利益相关者的主要兴趣。沉积物的运输和沉积是媒介中的地貌和所得栖息地的关键，进而决定了生物多样性。此外，对沉积物通量的了解对于确定基础设施的可持续性（水力发电，防洪），洪水风险，农业土壤损失和沐浴水安全至关重要。从传统上讲，最强大的良好的良好沉积物通量估计和污染物测量是来自连续的库存库或点采样。但是，在具有较大横截面和/或复杂且动态氢形态的河流中，通量在横截面上会大不相同。尽管通常认为细颗粒在整个流动的横截面中相对均匀分布，但这些颗粒的聚集可能意味着可能发生沉积物浓度的显着变化。鉴于这些变化在量化，理解不佳的情况下具有挑战性，并且在估计沉积物和污染物通量中可能很重要，这代表了优先研究领域。该项目的目的是首次解决精细沉积物和污染物运输中的这些横截面变化，以使沉积物预算估算，栖息地适用性评估以及对洪水风险的影响进行逐步改变。拟议的项目重点介绍了新型仪器的使用，以解决以前未经验证的新型污染物和其他污染物的使用。首先，将使用先进的未蛋式调查船获得同时的，共同置于河液压，悬浮沉积物和污染物的测量。其次，将研究观察到的变化，以阐明沉积物/污染物运输及其对照的横截面变化。通过在各种集水区设置以及各种流动条件下进行观察来获得知识。最先进的ADCP状态（声多普勒电流剖面仪）和多参数水质传感器将用于制造水流，河水液压，细沉积物和其他污染物测量。这些仪器将使用配备的差分GPS进行远程部署，可无线电控制的船（Arcboat和Arcboatlite），以允许对大型且经常难以接近的河流和洪泛区流进行安全的调查（请参阅照片）。 ADCP反向散射数据将对原位物理水样品（粒径和质量）以及独立的直接测量（浊度和粒径）进行评估，以提供强大的校准。这种复杂的校准程序特别适合研究项目，并将有助于提供优化的技术协议。多频率ADCP传感器应允许对沉积物颗粒尺寸及其空间分布的新见解，而高分辨率的河液压液压数据将有助于说明动员和沉积沉积物的环境，过程和条件。将其进行验证。在范围内，在范围内的范围和时间范围内，对跨越范围的范围进行了差异范围的范围划分的范围，从而有助于跨越群体的差异和差异范围的差异。这将为下游通量提供更准确的量化，从而提高了对控制沉积物和其他污染物运输的因素和过程的了解，从而使化学，生物学和生态状况以及沐浴水安全。