Sources and interpretation of channel complexity in forested subalpine streams of the Southern Rocky Mountains
Sources and interpretation of channel complexity in forested subalpine streams of the Southern Rocky Mountains
复制标题
落基山脉南部森林亚高山溪流河道复杂性的来源和解释
DOI：
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
E. Wohl
中科院分区：
文献类型：
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作者：
Bridget Livers;E. Wohl
我们评估流地貌的复杂性和特征的相邻河岸森林，山谷的几何形状，和土地利用的历史，在森林覆盖的亚高山溪流的科罗拉多前山脉之间的相关性。地貌复杂性的测量集中在横截面、平面形状和瞬时木片和木塞变量上。我们将相邻的河岸森林分为未受管理的老森林（OLD）、未受管理的年轻森林（YU）和受管理的年轻森林（YM），并将山谷几何形状分为横向受限、部分受限或非受限。在地貌流之间的显着差异，YU和YM的复杂性主要是从木材片和木塞的差异，这些差异与池量和有机质存储强烈相关。平面形状和横截面复杂性的显着差异与山谷几何形状的相关性更强，但并不能像木材变量那样解释所观察到的溪流之间复杂性的变化。无侧限的YM溪流具有最大的木材负荷和最大的复杂性，而伐木，领带驱动器和通道简化的遗留效应使YM溪流的复杂性降低，即使相对于流经类似年龄森林的YU溪流也是如此。我们发现，河岸林的管理历史发挥最强的控制功能减少流通道的复杂性，无论河岸林的林分年龄。
We evaluate correlations between stream geomorphic complexity and characteristics of the adjacent riparian forest, valley geometry, and land use history in forested subalpine streams of the Colorado Front Range. Measures of geomorphic complexity focus on cross‐sectional, planform, and instream wood piece and logjam variables. We categorize adjacent riparian forests as old‐growth unmanaged forest (OU), younger unmanaged forest (YU), and younger managed forest (YM), and valley geometry as laterally confined, partly confined, or unconfined. Significant differences in geomorphic stream complexity between OU, YU, and YM result primarily from differences in wood pieces and logjams, and these differences correlate strongly with pool volume and organic matter storage. Significant differences in planform and cross‐sectional complexity correlate more strongly with valley geometry, but do not explain as much of the observed variability in complexity between streams as do the wood variables. Unconfined OU streams have the largest wood loads and the greatest complexity, whereas legacy effects of logging, tie‐drives, and channel simplification create lower complexity in YM streams, even relative to YU streams flowing through similarly aged forest. We find that management history of riparian forests exerts the strongest control on reduced functional stream channel complexity, regardless of riparian forest stand age.