Conservation and Restoration of Aquatic Plants with Bed Erosion in Brackish Water Zone

本文讨论了波浪作用对主要生长在沿海地区的微咸水植物--日本结缕草建立的影响。利用安装在波浪水槽底床下的小型双分量称重传感器对日本对虾的波浪力进行了测量。波浪力太小，不能从底泥中拔出日本竹笋。还观察了波浪作用下的泥沙输移和河床形态发展，当波浪作用下沙床上出现大的波纹时，从水槽的沙床上拔出日本竹笋。进行了红树林和树木作为海岸防护的波浪传输和反射能力的实验研究。在小尺度明渠水流中，利用称重传感器测量了活体松树的阻力。还测量了圆柱体在急流中受到的阻力。应用流经树木的连续性方程和能量方程进行了理论分析，以评价沿海地区红树林和树木的透波和反射能力。估算了具有大而密树冠的红树林对海浪的显著反射。

The effect of wave action on the establishment of Zostera japonica, a brackish submerged macrophyte growing mainly in coastal areas, is discussed. The wave forces acting on Z. japonica were measured by using a small two components load cell installed under the bed of wave flume. The wave forces were too small to pull out Z. japonica shoot from bottom sediment. Sediment transport and bed form development under waves were also observed, and Z. japonica shoot was pulled out from the sand bed of flume when large ripples appeared on the sand bed in wave flume.Laboratory experiments were performed to study wave transmission and wave reflection capacity of mangroves and trees as coastal protection from waves. Drag forces on a live pine in small scale open channel flow were measured by using a load cell. Drag forces on a circular cylinder in rapid flow were also measured. A theoretical analysis based on application of the continuity and energy equations to flow through the rows of trees were made to evaluate wave transmission and wave reflection capacity of mangroves and trees in coastal area. The significant wave reflection from mangroves with large and dense canopy was estimated.