...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Earth Surface Processes and Landforms: The journal of the British Geomorphological Research Group >Living landscapes: Muddy and vegetated floodplain effects on fluvial pattern in an incised river
【24h】

Living landscapes: Muddy and vegetated floodplain effects on fluvial pattern in an incised river

机译：生活景观：泥泞和植被的洪泛区对一个切割河流的河流模式的影响

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Cohesive floodplain sediment and vegetation are both thought to cause meandering river patterns. Our aims are to compare the isolated and combined effects of mud and vegetation on river planform and morphodynamics in the setting of intermediate-sized valley rivers. We use a numerical model for century-scale simulation of flow, sediment transport and morphology coupled with riparian vegetation settlement, growth and mortality as functions of species traits on which flow resistance depends. Mud fluxes were predicted by excess shear stress relations in combination with the active layer formulation. We found that valley-flooding water levels increase with vegetation density, causing a higher braiding intensity rather than meandering tendency. The shear stress during floods carves channels through the muddy floodplain surface. Higher mud concentration, on the other hand, increases floodplain aggradation, reduces the overbank flow frequency and ultimately causes formation of a single-thread channel. Vegetation causes mud to deposit closer to the river channel as a levee, showing that mud sedimentation and vegetation settling mutually enhance floodplain formation. However, mud and vegetation counteract in two ways. First, vegetation enhances floodplain accretion, which ultimately increases plant desiccation for high mud concentrations. Second, vegetation increases the tendency of periodic chute cutoffs in valleys. The chute cutoffs locally reset the landscape and create new windows of opportunity for the vegetation. Surprisingly, in systems with a high mud concentration this causes hysteretic loops of vegetation cover and delayed mud deposition. Ramifications for the interpretation of Palaeozoic fluvial facies are that even rootless vegetation, capturing cohesive mud closer to the river channel to form thicker floodplain on the point bar, can enhance the tendency to meander and, under high mud supply, form stable channels. However, meandering is more unlikely in narrower valley rivers with higher vegetation density. (c) 2018 John Wiley & Sons, Ltd.
机译：粘性泛洪叶沉积物和植被都被认为是蜿蜒的河流模式。我们的旨在将泥浆和植被在河流河流河流河流河流中的泥浆和形态学性的分离和综合影响。我们使用具有河流植被沉降，生长和死亡率的世纪规模模拟流动，沉积物运输和形态，作为流动阻力的物种特征的函数。通过过量剪切应力关系与活性层配方结合预测泥浆助焊剂。我们发现谷洪水水平随植被密度而增加，导致更高的编织强度而不是蜿蜒的趋势。洪水期间的剪切应力通过泥泞的泛洪叶表面雕刻渠道。另一方面，泥浆浓度较高，增加了洪泛平原频率，降低了超过银行的流量频率，最终导致形成单线频道。植被导致泥浆沉积到河道作为堤坝的河流渠道，表明泥浆沉降和植被沉降相互增强泛洪叶形成。然而，泥浆和植被以两种方式抵消。首先，植被增强了泛洪叶增强，最终增加了高泥浆浓度的植物干燥。其次，植被增加了山谷中周期性滑槽截止的趋势。滑槽截止局在局部重置景观，并为植被创造新的窗口。令人惊讶的是，在具有高泥浆浓度的系统中，这导致植被覆盖的滞后环和延迟泥浆沉积。古生代河道的解释的后果甚至是甚至无根植被，捕捉到河流通道的粘性泥浆形成较厚的洪泛区，可以增强蜿蜒的倾向，并在高泥浆供应下形成稳定的通道。然而，在具有较高植被密度的较窄的山谷河流中，蜿蜒更不可能。 （c）2018 John Wiley＆Sons，Ltd。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号