Streambed restoration to remove fine sediment alters reach-scale transient storage in a low-gradient fifth-order river, Indiana, USA
Streambed restoration to remove fine sediment alters reach-scale transient storage in a low-gradient fifth-order river, Indiana, USA
复制标题
美国印第安纳州一条低梯度五级河流的河床恢复去除细泥沙改变了河段规模的临时蓄水
DOI：
10.1002/hyp.11518
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发表时间：
2018
影响因子：
3.2
通讯作者：
Royer, Todd V.
中科院分区：
文献类型：
--
作者：
Ward, Adam S.;Morgan, Joseph A.;White, Jeffrey R.;Royer, Todd V.
鉴于潜流带在支持生态系统服务和功能方面的作用，潜流恢复越来越受到关注。鉴于沉积物对水道的普遍污染，一种新兴的修复技术涉及从砾石床溪流的间隙中去除沉积物。在这里，我们记录了大量的细沉积物意外释放到砾石河床后的河床沉积物去除。我们将此作为一个自然实验来评估细沉积物去除对河段尺度瞬时蓄水量的影响，并记录不同形态河段（恢复与未恢复）对一个田间季节流量变化的响应。我们在每个河段进行了一系列保守的溶质示踪实验，解释了回收的流中溶质示踪时间序列的汇总统计数据。此外，我们应用暂态存储模型通过模型参数来解释结果，包括蒙特卡罗分析来测量每个实验中参数的可识别性和灵敏度。尽管修复工作在恢复河段形成了开放基质砾石床，但我们没有发现描述河段尺度迁移和瞬态储存的大多数时间序列指标有显著差异。我们假设这是由于恢复河段与砾石床的垂直交换增强，取代了未恢复河段与大型植物床的横向交换，并开发了一个概念模型来解释我们的发现。因此，我们发现，使用达尺度溶质示踪剂研究无法测量精细沉积物的达尺度去除的影响。我们为未来的研究提供了建议，以寻求在河段尺度上衡量河流恢复的影响。
Hyporheic restoration is of increasing interest given the role of hyporheic zones in supporting ecosystem services and functions. Given the prevalence of sediment pollution to waterways, an emerging restoration technique involves the removal of sediment from the interstices of gravel‐bed streams. Here, we document streambed sediment removal following a large, accidental release of fine sediment into a gravel‐bed river. We use this as a natural experiment to assess the impact of fine sediment removal on reach‐scale measures of transient storage and to document the responses of reaches with contrasting morphology (restored vs. unrestored) to changing discharge one‐field season. We conducted a series of conservative solute tracer experiments in each reach, interpreting both summary statistics for the recovered in‐stream solute tracer time series. Additionally, we applied the transient storage model to interpret the results via model parameters, including a Monte Carlo analysis to measure parameter identifiability and sensitivity in each experiment. Despite the restoration effort resulting in an open matrix gravel bed in the restored reach, we did not find the significant differences in most time series metrics describing reach‐scale transport and transient storage. We hypothesize that this is due to enhanced vertical exchange with the gravel bed in the restored reach replacing lateral exchange with macrophyte beds in the unrestored reach, developing a conceptual model to explain our findings. Consequently, we found that the impact of reach‐scale removal of fine sediment is not measureable using reach‐scale solute tracer studies. We offer recommendations for future studies seeking to measure the impacts of stream restoration at the reach scale.