Estuaries worldwide have evolved over the past few centuries under development activities like dredging and shoreline reclamation, which commonly lead to increased channel depths and reduced intertidal areas. The Coos Estuary offers a useful example of how these changes, common to diverse global estuaries, have altered tidal and salt dynamics, with implications for estuarine habitats. In the past 150 years, the primary navigation channel has been deepened from ~ 6.7 to 11 m, generating a 12% decrease in estuary area and 21% increase in volume. To evaluate the present and future impacts on the Coos and similar estuaries, a hydrodynamic model was implemented using a detailed bathymetric dataset compiled from multiple data sources including agency charts, water-penetrating lidar, and single-beam-sonar small-vessel surveys. The model was then re-run using grids constructed from 1865 survey data and a future proposed dredging plan. Changes in the hypsometry from 1865 to present have driven a 33% increase in tidal amplitude, an 18% increase in salinity intrusion length, a doubling of the subtidal salt flux, and an increase in ebb dominance of currents. A proposed channel-depth increase from 11 to 14 m is predicted to generate a negligible change in tidal range and a small increase in the salinity intrusion length. These results highlight the utility of curating high-resolution bathymetric datasets for coastal management applications through modeling. The historical and modern models quantify how local bathymetric modifications can significantly alter tidal and salinity regimes and provide context for estuarine response to global climate-change drivers.

在过去的几个世纪中，全球河口在诸如挖泥和海岸线填海之类的开发活动中不断发展，这些活动通常导致河道深度增加和潮间带减少。库斯河口提供了一个有用的例子，说明这些变化是全球性河口常见的变化，如何改变潮汐和盐分动态，对河口栖息地产生影响。在过去的150年中，主要导航通道已从〜6.7加深到11 m，河口面积减少了12％，流量增加了21％。为了评估当前和未来对库斯河和类似河口的影响，使用了详细的测深数据集来实现水动力模型，该数据集是从多个数据源编译而成的，包括代理图，透水激光雷达和单波束声纳小容器调查。然后使用从1865年的调查数据构建的网格和未来提议的疏plan计划重新运行该模型。从1865年到现在，催眠术的变化导致潮汐幅度增加了33％，盐分侵入长度增加了18％，潮汐下盐通量增加了一倍，电流的起伏优势增加。预计拟议的河道深度从11 m增加到14 m，潮汐范围的变化可忽略不计，盐分侵入长度的增加很小。这些结果凸显了通过建模为沿海管理应用策划高分辨率测深数据集的实用性。历史和现代模型量化了局部测深的修改如何显着改变潮汐和盐度状况，并为河口对全球气候变化驱动因素的响应提供了背景。