Dynamics of Fine Particle Organic Matter at forested watershed - Challenging of New Management of River Environment -

颗粒有机质为细菌和水生昆虫提供食物，是保护和修复水生环境的重要特征。底栖细颗粒有机质（FBOM）是指在洪水条件下大量输出的细颗粒有机质的沉积形式。但对FBOM冲刷沉降机理的研究尚不清楚。本研究的目的是分析FBOM丰度对洪水事件的影响因素。结果表明：①水厂堰上游FBOM丰度的波动与FBOM大小分布不同；②洪水事件中FBOM丰度在水位上升期间呈下降趋势，但在水位下降期间FBOM丰度大多呈上升趋势。

Particle organic matters is an important feature of the conservation and renovation of an aquatic environment, because of providing the food for bacterias and aquatic insects. Fine Benthic Organic Matters (FBOM), which is sedimented forms of fine particle organic matters exported largely in a flood condition. But the examination of the mechanism of FBOM flushing and sedimentating is not known well. The purpouse of this study is the analysis of the affected factors on the abundance of FBOM on the flood event. The results at upstream of the weir of hydraulic plant show that 1)the fluctuation of the abundance of FBOM were different from FBOM size distribution, 2)the abundance of FBOM were decreased during the water level increasing period, but mostly the abundance of FBOM were increased during the water level decreasing period at the flood event.