Development of "Steel-made mat" the industrial method stabilizing at sea bottom for eelgrass-beds creation
2006
Moriguchi, A.(National Research Inst. of Fisheries Engineering, Hasaki, Ibaraki (Japan)) | Takagi, N. | Yamamoto, J. | Omura, T. | Yoshida, G. | Terawaki, T. | Tanada, N. | Yamanoi, H.
Sea grass beds will continue to decrease. One of the causes is deemed the effect of intensified waves and currents, which result from plain-shaped coasts due to bulkhead construction in addition to the destruction of sea grass beds directly caused by reclamation. Sand and mud at sea bottom, where sea grasses take roots, are readily moved and sea grasses are dug out to run off, leading to the degeneration of sea grass beds. Environment with quit waves is important for restoring sea grass beds. However, the construction of large structures such as breakwaters not only costs a huge amount of money but also changes surrounding environment significantly. In order to stabilize sand and mud movement at sea bottom while conserving surrounding environment as much as possible, an idea to sheet sea bottom with pieces of a structure similar to floor cushion was conceived. Sea grass seeds imbedded in the structure germinate and grow through voids provided in it. Steel plates and steel nets were used as the material to avoid adverse effects on environment. Hence, the structure was named "steel-made mat". After grasping their basic stabilization functions at sea bottom by laboratory experiments, a construction test at site was carried out in an actual sea region. As a result, a sea grass population as dense as natural ones was formed.
Показать больше [+] Меньше [-]