Monsoon wave transmission at bamboo fences protecting mangroves in the lower mekong delta

This paper is concerned with a study on monsoon wave transmission at bamboo fences protecting newly-planted mangroves in the Lower Mekong Delta (LMD) of Vietnam. For this, new field experiments were carried out in combination with the use of an existing field dataset by Albers et al. (2013).

In support of the analysis of the field data, influences of governing parameters on wave transmission are systematically examined using a numerical wave tank (i.e. a RANS-VOF model). It follows that the fence height is relatively more influential than the fence width. Also, high-frequency waves are generally more effectively dissipated by the fences than long-frequency waves. Importantly, the fence porosity is found to affect attenuation of both high- and low-frequency waves drastically, indicating its important role in the quantitative understanding of wave transmission as well as in the fence functional design.

An empirical formulation of wave transmission at bamboo fences, needed for the fence functional design, was eventually derived from all the field data. As hinted at by the numerical analysis, the fence freeboard, the fence width and especially the fence porosity are found the major governing parameters.

1. Introduction

2. Field experiments and used datasets

2.1. Wave transmission coefficient

2.2. New experiments

2.3. Existing GIZ dataset

2.4. Combination of datasets

3. Numerical analysis

3.1. Model description

3.2. Model setup and validations

3.3. Wave-fence interaction

3.4. Influences of fence parameters

4. Empirical formulation

5. Discussion

6. Summary and concluding remarks

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Tuan Thieu Quanga,⁎, Luan Mai Trongb
a Thuyloi University, 175 Tay Son, Dong Da, Hanoi, Vietnam
b Institute of Ecology and Works Protection, Vietnam Academy for Water Resources, Hanoi, Vietnam

Applied Ocean Research