A conceptual model for the longitudinal distribution of wood in mountain streams
A conceptual model for the longitudinal distribution of wood in mountain streams
复制标题
山间溪流中木材纵向分布的概念模型
DOI：
10.1002/esp.1722
复制
发表时间：
2009
影响因子：
3.3
通讯作者：
K. Jaeger
中科院分区：
文献类型：
--
作者：
E. Wohl;K. Jaeger
木材负荷，通道参数和山谷参数进行了调查，在50个连续的流段，每个25米长沿着12流在科罗拉多前线范围。测量了每一块木头的长度和直径，并将每一块木头的方向记录为斜坡、掩埋、桥接或未连接。然后，这些数据被用来评估木材分布的纵向模式，在森林的源头流的科罗拉多前山脉，和潜在的通道，山谷和流域尺度控制这些模式。我们假设：（i）木材负荷在下游减少，（ii）由于木材堵塞的存在，木材在几十到几百米的河道长度上是非随机分布的，（iii）由于下游河流运输从相邻河岸带和谷底引入的木材的相对能力增加，聚集在堵塞中的木材的比例随着流域面积的增加而增加。结果表明，木材负荷的渠道内，木材负荷和流域面积，海拔，渠道宽度，河床坡度和总水流功率之间的相关性，逐步下游减少。结果支持第一和第二个假设，但不确定的第三个假设。木材在几十到几百米的长度上是非随机分布的，但堵塞的木材比例在研究区域内的下游距离达到最大值。我们使用这些结果提出了一个概念模型，说明下游趋势的木材内流的科罗拉多前线范围。版权所有© 2009约翰威利父子有限公司。
Wood load, channel parameters and valley parameters were surveyed in 50 contiguous stream segments each 25 m in length along 12 streams in the Colorado Front Range. Length and diameter of each piece of wood were measured, and the orientation of each piece was tallied as a ramp, buried, bridge or unattached. These data were then used to evaluate longitudinal patterns of wood distribution in forested headwater streams of the Colorado Front Range, and potential channel‐, valley‐ and watershed‐scale controls on these patterns. We hypothesized that (i) wood load decreases downstream, (ii) wood is non‐randomly distributed at channel lengths of tens to hundreds of meters as a result of the presence of wood jams and (iii) the proportion of wood clustered into jams increases with drainage area as a result of downstream increases in relative capacity of a stream to transport wood introduced from the adjacent riparian zone and valley bottom. Results indicate a progressive downstream decrease in wood load within channels, and correlations between wood load and drainage area, elevation, channel width, bed gradient and total stream power. Results support the first and second hypotheses, but are inconclusive with respect to the third hypothesis. Wood is non‐randomly distributed at lengths of tens to hundreds of meters, but the proportion of pieces in jams reaches a maximum at intermediate downstream distances within the study area. We use these results to propose a conceptual model illustrating downstream trends in wood within streams of the Colorado Front Range. Copyright © 2009 John Wiley & Sons, Ltd.