بررسی اثر شیب ساحل بر میرایی امواج منفرد شکنا در سواحل با پوشش گیاهی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 فارغ التحصیل مقطع کارشناسی ارشد / دانشگاه شهید چمران اهواز

2 استاد / دانشگاه شهید چمران اهواز

چکیده

همه ساله حملات امواج بلندی همچون سونامی باعث ایجاد فرسایش و تخریب در سواحل شده و خسارات جانی و مالی فراوانی را به بار می‌آورند. رویکردهای اخیر حفاظت سواحل بر مبنای برقراری تعادل زیست‌محیطی می‌باشد. از جمله روش‌های نوین حفاظت سواحل در مقابل تخریب ناشی از امواج، احداث جنگل‌های ساحلی موسوم به کمربند سبز ساحلی می‌باشد. شیب ساحل از جمله عوامل بسیار تأثیرگذار بر شکست موج و بالاروی آن در سواحل است. از این رو مطالعه حاضر با هدف بررسی اثر شیب ساحل بر جذب نیروی مخرب امواج شکنا توسط پوشش گیاهی ساحلی صورت گرفته است. به‌همین منظور مدل ساحل شیبدار و پوشش گیاهی در یک فلوم مجهز به سیستم نیروسنجی بدون اصطکاک تعبیه شد. آزمایش‌ها در چهار شیب مختلف ساحل و در دو حالت با و بدون پوشش گیاهی انجام شده است. نتایج نشان داد که با افزایش شیب ساحل، موج زودتر می‌شکند و در نتیجه نیروی بیشتری از موج توسط پوشش جنگلی جذب می‌شود. این افزایش نیروی جذب شده از موج در شیب‌های مختلف در حالت با پوشش نسبت به بدون پوشش به‌طور میانگین 17 درصد بود.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of coast slope on solitary breaking waves attenuation by coastal vegetation

نویسندگان [English]

  • Ali Motamedi Nezhad 1
  • Manouchehr Fathi-Moghadam 2
1 MSc. Graduated / Shahid Chamran University of Ahwaz
2 Professor / Shahid Chamran University of Ahwaz
چکیده [English]

Every year, long waves attacks such as tsunamis cause coastal erosion and destruction and bring irreparable damages to the life and properties of people. Recent approaches of coastal protection are based on environmental balance. Of the new methods of coastal protection against destructive force of waves is planting coastal forest known as green belt. Coast slope is one of effective factors which contributes with the wave breaking condition and wave run-up. Hence, the aim of present study is to investigate the effect of coast slope on solitary breaking waves attenuation by coastal forest. To this purpose, a sloping coast and a coastal vegetation model were installed in a flume equipped to a frictionless force measurement system. The experiments were conducted in four different coast slopes in both with coastal vegetation and without coastal vegetation mode. The results indicated that increase of the coast slope causes the waves to break faster into vegetation area, hence more wave force absorption. The amount of the wave force reduction in presence of vegetation in comparison with the non-vegetated condition in different coast slopes was 17 percent on average.

کلیدواژه‌ها [English]

  • Coastal green belt
  • long waves
  • wave breaking
  • coast slope
  • wave force
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