The Effect of Coastal Forest on Variations of Broken Wave Force and Inundation Depth

Document Type : Research Paper



Wave breaking in the nearshore zone and then its run up are the main reasons for erosion and destruction of coasts. This causes huge human and financial disasters. Recent coastal protection approaches are based on ecological and environmental balance on the coasts. One of the new coastal protection methods against destruction of waves like tsunami is planting coastal forests that named “coastal green belt”. Coastal forest protection to decrease destruction is based on increasing flow resistance. Therefore, the present study is with purpose of the coastal forest effects on variations of force and inundation of broken waves. For this respect, all of the tests were conducted for 25 heights of incoming waves to Nearshore model with 9% slop in two with and without coastal forest in a flume with length of 8.3m, 0.8 m width, 0.5m height and equipped to a force measurement system. The results of the study show that the coastal forest cause the maximum destructive force and inundation depth of broken waves of an average mitigation of 74 and 40 percent, of 74 and 40 percent, respectively.


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