城市化和悬浮沉积物运输动态:对不同程度城市化的流域进行比较研究,使用度 - 排放歇斯底里
Suffiyan Safdar1, Anne J Jefferson2, David M Costello3
1Department of Civil & Environmental Engineering, University of Vermont, 33 Colchester Avenue, Burlington, Vermont 05405, United States.
概括
城市河流沉积物的动态与典型的污染物模型不同. 增加的不透气表面将沉积物供应从上游来源转移到下游侵蚀,影响水质和地形.
科学领域:
- 环境科学 环境科学
- 水文学 水文学
- 地质形态学 地质形态学
背景情况:
- 悬浮沉积物是一个关键的水质指标和地形过程标记.
- 城市流动力学,特别是悬浮沉积物,可能不遵循其他污染物使用的首次冲洗模型.
研究的目的:
- 分析城市河流中悬浮沉积物的动态,其覆盖面不同且不透.
- 调查流域城市化,沉积源和歇斯底里模式之间的关系.
主要方法:
- 对来自俄俄州克利夫兰三个城市流域的367个事件的排放和度数据的分析.
- 地形分析以确定驱动沉积物歇斯底里的潜在机制.
主要成果:
- 城市化程度较低的流域比城市化程度较高的流域具有较高的度.
- 歇斯底里模式各不相同:在城市化程度较低的地区逆时针方向,在城市化程度较高的水域则顺时针方向.
- 沉积物来源随着城市化的增加,从降雨变化转移到河流内岸侵蚀.
结论:
- 城市化改变了悬浮沉积物的动态,随着透度的增加,入流沉积物变得更加关键.
- 地形学对于理解和管理城市河流沉积过程至关重要.
- 第一次冲洗模型可能无法准确地代表城市溪流中悬浮沉积物的行为.
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