We use four stream segments along a wood‐rich, pool–riffle mountain stream in the Southern Rockies of Colorado, USA to examine how spatial variations in wood load and variations in discharge during and after the snowmelt peak flow influence the magnitude of surface and subsurface transient storage. Segments range in complexity from a single channel with no large wood to an anabranching channel with closely spaced, channel‐spanning logjams. Discharges at which transient storage was assessed range from base flow to snowmelt peak flow. To explore these relations, we used 10 geomorphic variables representing channel morphology and bed substrate, four wood‐related variables representing wood load and associated backwater storage, and two measures of skewness from instream and bulk electrical conductivity breakthrough curves during tracer tests. Instream curves reflect surface and subsurface transient storage, whereas bulk curves primarily represent subsurface transient storage. Higher values of skewness indicate greater retention, and we used the values here as a metric of increased transient storage. Although limited sample size restricts the power of our results, our findings suggest that stream segments with greater instream large wood loads have more and larger pools, greater storage of fine sediment and particulate organic matter, and higher values of skew from instream conductivity. The results also suggest that the presence of instream wood, rather than changes in channel morphology associated with wood, is the most important driver of transient storage. This implies that river management designed to foster transient storage should focus on retaining instream large wood. We did not find significant correlations between geomorphic or wood‐related variables and the skew estimated from bulk conductivity, which may reflect the relatively thin alluvium present in the field area and the prevalence of surface transient storage in this system.

中文翻译：

---

Logjams是山间溪流中暂态存储的驱动力

我们在美国科罗拉多州南部洛矶山脉的一条富含木材，水池和浅滩的山间溪流中使用四个溪流段，以研究融雪峰值流期间和之后，木材负荷的空间变化以及排放量的变化如何影响地表和次表层的大小。临时存储。片段的复杂度范围从没有大木材的单个通道到具有紧密间隔的通道跨度的堵塞的垂直通道。评估临时存储的流量范围从基本流量到融雪峰值流量。为了探索这些关系，我们使用了10个代表通道形态和床底物的地貌变量，四个与木材有关的变量代表了木材负荷和相关的回水存储，以及在示踪剂测试中从流量和体积电导率穿透曲线的两个偏斜度的度量。入流曲线反映了地表和地下的瞬态存储，而体积曲线主要代表了地下的瞬态存储。偏度值越高，表示保留越强，在这里我们将这些值用作增加瞬态存储的指标。尽管有限的样本量限制了我们结果的效力，但我们的研究结果表明，河道中较大的木料负荷较大的河段具有越来越大的水池，细小沉积物和颗粒有机物的存储量更大，并且因河道电导率而产生的偏斜值更高。这些结果还表明，流入木材的存在而不是与木材相关的河道形态变化是暂时存储的最重要驱动力。这意味着旨在促进临时存储的河流管理应着重保留上游大块木材。