کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6431721 1635396 2016 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Influence of reef geometry on wave attenuation on a Brazilian coral reef
ترجمه فارسی عنوان
تأثیر هندسه صخره ای بر ضخامت موج در یک صخره مرجانی برزیل
کلمات کلیدی
فرسایش ساحلی، انتقال موج، مورفولوژی ریف ساحلی،
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
چکیده انگلیسی


- We quantify wave attenuation related to reef morphology.
- Wave transmission depends on reef morphology.
- A critical water level threshold for wave transmission is defined.
- Wave transmission depends on incident wave height beyond the critical water level.
- Wave attenuation on shallow reefs is highly sensitive to water level changes.

This study presents data from field experiments that focus on the influence of coral reef geometry on wave transformation in the Metropolitan Area of Recife (MAR) on the northeast coast of Brazil. First, a detailed bathymetric survey was conducted, revealing a submerged reef bank, measuring 18 km long by 1 km wide, parallel to the coastline with a quasi-horizontal top that varies from 0.5 m to 4 m in depth at low tide. Cluster similarity between 180 reef profiles indicates that in 75% of the area, the reef geometry has a configuration similar to a platform reef, whereas in 25% of the area it resembles a fringing reef. Measurements of wave pressure fluctuations were made at two stations (experiments E1 and E2) across the reef profile. The results indicate that wave height was tidally modulated at both experimental sites. Up to 67% (E1) and 99.9% (E2) of the incident wave height is attenuated by the reef top at low tide. This tidal modulation is most apparent at E2 due to reef geometry. At this location, the reef top is only approximately 0.5 m deep during mean low spring water, and almost all incident waves break on the outer reef edge. At E1, the reef top depth is 4 m, and waves with height ratios smaller than the critical breaking limit are free to pass onto the reef and are primarily attenuated by bottom friction. These results highlight the importance of reef geometry in controlling wave characteristics of the MAR beaches and demonstrate its effect on the morphology of the adjacent coast. Implications of differences in wave attenuation and the level of protection provided by the reefs to the adjacent shoreline are discussed.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Geomorphology - Volume 253, 15 January 2016, Pages 318-327
نویسندگان
, , , ,