| 农田溪流人工深潭地貌格局暂态存储特征分析 |
| 摘要点击 1707 全文点击 831 投稿时间：2016-03-08 修订日期：2016-03-24 |
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| 中文关键词 人工深潭 暂态存储 农田源头溪流 OTIS模型 浅滩-深潭序列 |
| 英文关键词 artificial pool transient storage agricultural headwater stream OTIS model riffle-pool sequence |
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| 中文摘要 |
| 2015年11月~2016年2月，以NaCl为示踪剂，在巢湖流域某一农田源头溪流开展了5次野外示踪试验，并据此计算溪流的物理特征参数和暂态存储指标；通过对深潭渠段与平直渠段相关指标的比较，解析人工深潭地貌格局的暂态存储特征. 结果表明：①人工深潭地貌格局渠段As/A基本都较平直渠段更高，但其交换系数α却较平直渠段低一个数量级；②人工深潭地貌格局的暂态存储对于溶质滞留的影响较平直渠段大，但其流动水体的溶质滞留能力则较平直渠段弱；③尽管深潭地貌格局拥有相对较大的As/A比值，但对溶质运移转化的综合影响却低于平直渠段；④人工深潭的暂态存储指标F200med可以解释18.86%~26.05%的溶质行进时间，平直渠段可以解释5.28%~33.87%，且大部分情况下平直渠段都较深潭渠段更高；⑤深潭地貌格局与平直渠段在φw、φA和Ts方面差异明显，而在其他指标方面则区别不显著. |
| 英文摘要 |
| From November 2015 to February 2016, five short-term tracer injections were performed with a conservative tracer (NaCl) in an agricultural headwater stream, Lake Chaohu basin. Thus the data sets of tracer experiments were finally employed for calculating the physical characteristics and transient storage metrics. Through the comparisons between the artificial pool reach and straight reach, characteristics of transient storage for the artificial pool geomorphic structure were interpreted and explored. Study results showed that: ① The ratio of As/A in artificial pool was larger than that in straight reach, whereas its value of exchange coefficient α was lower by an order of magnitude than that of straight reach. ② Artificial pool geomorphic structure had greater influence of transient storage on solute retention than that in straight reach, but its solute retention capacity of flowing water was weaker than that of straight reach. ③ It had a large ratio of As/A for the pool geomorphic structure, whereas its impact on the migration and transformation of solutes was less than that of straight reach. ④ Based on the Fmed200 metric, the transient storage accounted for 18.86% to 26.05% of travel time in artificial pool. For the straight reach, the Fmed200 metric had a range of 5.28% to 33.87%. In most cases, the values of Fmed200 metric in straight reach were higher than those in artificial pool. ⑤ Significant differences existed between artificial pool geomorphic structure and straight reach in the values of φw, φA and Ts, however, the differences were not significant in other indicators. |
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