量化形式阻力对于估计夏季低流和河流调查道形态的银行全流是必不可少的
Philip R Kaufmann1,2, Daren M Carlisle3, John M Faustini4
1U.S. Environmental Protection Agency, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, 200 SW 35th Street, Corvallis, OR 97333, USA.
概括
使用道形态来估计流排放,考虑到大木材和流水池的粗度,为未经处理的地点提供可靠的低流量和大量的洪水数据. 这种方法改善了在传统口无法使用的地方进行生态评估.
科学领域:
- 水文学的水文学
- 环境科学 环境科学
- 地质形态学 地质形态学
背景情况:
- 估计未开放地点的溪流排放对于水资源管理,息地评估和基础设施设计至关重要.
- 传统的河流阻塞通常仅限于小的,偏远的河流或具有复杂道形态的河流.
- 复杂的道具有大规模的粗元素 (形状粗) 对传统的排放估计方法构成挑战.
研究的目的:
- 使用物理息地数据开发和验证一种新的方法来估计低流量和bankfull排放.
- 为了明确考虑大型木材和流水池形态 (形状粗性) 的液压阻力.
- 提供可靠的排放估计,对各种大小和复杂度的无水道溪流和河流.
主要方法:
- 利用了通过国家河流和溪流评估 (NRSA) 收集的来自美国境内的4,229个溪流和河流地点 (CONUS) 的物理息地数据.
- 开发了一种方法,将形状粗性 (大木材,水池) 和粒子阻力纳入液压计算中.
- 根据直接现场测量和美国地质调查局 (USGS) 测量数据验证的基于形态的排放估计.
主要成果:
- 形状的粗性显著影响了液压阻力,特别是在夏季可以水的溪流的低流量期间.
- 基于形态的低流量估计显示了与2,333个CONUS流中的现场测量有合理的一致性 (<2.5倍的中位数差异).
- 银行满流量和夏季低流量估计与美国地质调查局对较大的溪流和河流的标尺数据有很好的相关性 (平均偏差分别为<2.0x和<2.2x).
结论:
- 量化来自大规模形式粗性的流电阻对于在自然通道中准确估计排放是必不可少的.
- 这种基于形态学的方法为评估排放及其在缺乏传统数据的情况下对生态的影响提供了有价值的工具.
- 该方法支持对流量变化的区域分析及其与水生生物和人类干扰的关联.
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