Using the colour of recent overbank sediment deposits in two large catchments to determine sediment sources for targeting mitigation of catchment-specific management issues.
Using the colour of recent overbank sediment deposits in two large catchments to determine sediment sources for targeting mitigation of catchment-specific management issues.
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DOI：
10.1016/j.jenvman.2023.117657
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发表时间：
2023-03
影响因子：
8.7
通讯作者：
S. Pulley;A. L. Collins
中科院分区：
文献类型：
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作者：
S. Pulley;A. L. Collins
有效管理大型河流系统的沉积物流失对于维持其提供的水资源和生态系统服务至关重要。然而，预算和后勤方面的限制往往意味着无法了解进行有针对性的管理所必需的流域沉积物动态。本研究尝试收集最近沉积的漫滩沉积物，并使用办公室文件扫描仪测量其颜色，以确定沉积物来源的演变迅速和廉价的两个大河流集水区在英国。怀伊河集水区在农村和城市地区都经历了与洪水后细沉积物沉积有关的巨额清理费用。在南泰恩河，细沙污染了饮用水的提取，细粉砂使鲑鱼产卵的栖息地退化。在这两个集水区，收集了最近沉积的漫滩沉积物样品，分级为<25 μm或63-250 μm，并在颜色测量前用过氧化氢处理以去除有机物。在怀伊河集水区，已查明各来源对下游地质单元的贡献增加，这是由于可耕地比例增加。在此基础上，众多的支流排放不同的地质允许漫滩沉积物沉积物质。在南泰恩河流域，沉积物来源的下游变化，初步发现。东艾伦河被确定为一个具有代表性的和实际的支流子流域进行进一步调查。收集的渠道银行材料和表土的样本，其中允许渠道银行被确定为主要的沉积物来源，增加，但小的贡献，从表土在下游方向。在这两个研究集水区，漫滩沉积物的颜色可以快速和廉价地通知集水区管理措施的改进目标。
The effective management of sediment losses in large river systems is essential for maintaining the water resources and ecosystem services they provide. However, budgetary, and logistical constraints often mean that the understanding of catchment sediment dynamics necessary to deliver targeted management is unavailable. This study trials the collection of accessible recently deposited overbank sediment and the measurement of its colour using an office document scanner to identify the evolution of sediment sources rapidly and inexpensively in two large river catchments in the UK. The River Wye catchment has experienced significant clean-up costs associated with post-flood fine sediment deposits in both rural and urban areas. In the River South Tyne, fine sand is fouling potable water extraction and fine silts degrade salmonid spawning habitats. In both catchments, samples of recently deposited overbank sediment were collected, fractionated to either <25 μm or 63-250 μm, and treated with hydrogen peroxide to remove organic matter before colour measurement. In the River Wye catchment, an increased contribution from sources over the geological units present in a downstream direction was identified and was attributed to an increasing proportion of arable land. Numerous tributaries draining different geologies allowed for overbank sediment to characterise material on this basis. In the River South Tyne catchment, a downstream change in sediment source was initially found. The River East Allen was identified as a representative and practical tributary sub-catchment for further investigation. The collection of samples of channel bank material and topsoils therein allowed channel banks to be identified as the dominant sediment source with an increasing but small contribution from topsoils in a downstream direction. In both study catchments, the colour of overbank sediments could quickly and inexpensively inform the improved targeting of catchment management measures.