Patterns of sediment production and outflow required for creation and maintenance of stream habitat structure

在一组不同森林砍伐和泥石流历史的溪流中，研究了栖息地结构和底栖无脊椎动物群落结构与产沙量和流出量的关系。微生境多样性在最后一次砍伐森林和/或最后一次泥石流之后的特定时期显示出最大值。基质上苔藓覆盖率和裸露石块与部分埋藏石块的比例可以用产沙量和河床宽度的综合因素来解释。此外，通过对大坝水库尾水河段的现场观测和以松花粉为示踪剂的室内实验，发现沙坝结构的发育提高了悬浮颗粒有机物(SPOM)的捕集效率。

Relations of habitat structure and benthic invertebrate community structure to the amount of sediment production and outflow were studied in a set of mountain streams different in histories of deforestation and debris flow. Microhabitat diversity showed the maximum values in a specific period after the last deforestation and/or the last debris flow. Coverage of moss mat on substrates and ratio of exposed stones to partially buried stones could be explained by combined factors of sediment production and the riverbed width. Furthermore, we found that development of sandy bar structure enhanced the trapping efficiency of suspended particulate organic matter (SPOM) by the field observation in the tailwater reaches of dam reservoir and by the laboratory experiment using pine pollens as an SPOM tracer.