Study on the effect of seagrass meadows to mitigate coastal erosion: A case study of Le Morne, Mauritius
(2025) In TVVR 5000 VVRM01 20251Division of Water Resources Engineering
- Abstract
- This thesis studies the impact that seagrass meadows have in terms of attenuating incoming wave heights and mitigating coastal erosion. Specifically, this study seeks to investigate how seagrass meadows impact the coastline by looking at the longshore sediment transport, which has been identified as the key erosion process. This will be done by looking at the case study of Le Morne on Mauritius. The thesis emphasizes how an increase in extents and densities of the seagrass meadows will decrease sediment transport rates and also argues for the use of these nature-based solutions over hard structures to combat coastal erosion. In addition, the impact of sea level rise on the shoreline was investigated since climate change is a rising... (More)
- This thesis studies the impact that seagrass meadows have in terms of attenuating incoming wave heights and mitigating coastal erosion. Specifically, this study seeks to investigate how seagrass meadows impact the coastline by looking at the longshore sediment transport, which has been identified as the key erosion process. This will be done by looking at the case study of Le Morne on Mauritius. The thesis emphasizes how an increase in extents and densities of the seagrass meadows will decrease sediment transport rates and also argues for the use of these nature-based solutions over hard structures to combat coastal erosion. In addition, the impact of sea level rise on the shoreline was investigated since climate change is a rising concern. A conceptual model was set up consisting of a wave model in SWAN, which is a program for simulating nearshore waves. Then, calculations of the corresponding sediment transport rates along the shoreline were performed using the CERC formula. Through data analysis, the thesis showcases that the surrounding reef plays a key role in attenuating incoming wave energy since the wave height is drastically reduced once the waves pass over the reef. Moreover, the thesis highlights how a large extent, high density seagrass meadow will significantly reduce the incoming wave height, thus leading to lower sediment transport rates and coastal erosion on the shoreline. Finally, recommendations, ranging from stricter regulations to a transplantation program, are provided and discussed further in order to combat the rate of sediment transport and coastal erosion occurring in Le Morne. (Less)
- Popular Abstract
- This thesis studies the impact of seagrass meadows on coastal erosion. Studies have shown that high wave heights produce more coastal erosion compared to lower wave heights. Thus, this study assesses how much seagrass meadows can diminish the wave heights and highlights how this vegetation can be used as a so called nature-based solution to protect the shoreline by mitigating coastal erosion. The incoming wave height was identified as a key factor of longshore sediment transport, where wave action leads to the displacement of the sand along the coastline. This displacement was identified as a key factor for coastal errosion.
These processes were analysed for the case study of Le Morne on the main island of Mauritius. The thesis emphasizes... (More) - This thesis studies the impact of seagrass meadows on coastal erosion. Studies have shown that high wave heights produce more coastal erosion compared to lower wave heights. Thus, this study assesses how much seagrass meadows can diminish the wave heights and highlights how this vegetation can be used as a so called nature-based solution to protect the shoreline by mitigating coastal erosion. The incoming wave height was identified as a key factor of longshore sediment transport, where wave action leads to the displacement of the sand along the coastline. This displacement was identified as a key factor for coastal errosion.
These processes were analysed for the case study of Le Morne on the main island of Mauritius. The thesis emphasizes how an increase in extents and densities of the seagrass meadows will decrease sediment transport rates. It compares seagrass meadows to other structures whoch can be built to protect the coastline from erosion. The thesis argues that hard structures made from concrete can have many negative impacts and acually accelerate erosive activity.
In addition, since climate change is a ising concern, the impact of sea level rise on the shoreline was investigated. A wave model was set up in SWAN, which is a program for simulating nearshore waves. Then, the corresponding sediment transport rates along the shoreline were calculated. Based on the results, the following conclusions could be made:
The thesis highlights that a wise, high density seagrass meadow will significantly reduce the incoming wave height, thus leading to lower sediment transport rates and coastal erosion on the shoreline. Moreover, resommendations to improve and protect the segrass meadows in the study area such as stricter regulations for water sports and a transplantation program are discussed. In addition, the thesis focusses on the reef which surrounds the study area and emphasizes its importance to break waves and protect the shoreline. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9194799
- author
- Glatthaar, Julia LU and Espinosa, Paola Lucia LU
- supervisor
- organization
- course
- VVRM01 20251
- year
- 2025
- type
- H2 - Master's Degree (Two Years)
- subject
- keywords
- sediment transport, coastal erosion, SWAN, nature-based solutions, SIDS, seagrass
- publication/series
- TVVR 5000
- report number
- TVVR25/5001
- ISSN
- 1101-9824
- language
- English
- additional info
- Examiner: Magnus Larson
- id
- 9194799
- date added to LUP
- 2025-06-11 13:31:53
- date last changed
- 2025-06-11 13:31:53
@misc{9194799,
abstract = {{This thesis studies the impact that seagrass meadows have in terms of attenuating incoming wave heights and mitigating coastal erosion. Specifically, this study seeks to investigate how seagrass meadows impact the coastline by looking at the longshore sediment transport, which has been identified as the key erosion process. This will be done by looking at the case study of Le Morne on Mauritius. The thesis emphasizes how an increase in extents and densities of the seagrass meadows will decrease sediment transport rates and also argues for the use of these nature-based solutions over hard structures to combat coastal erosion. In addition, the impact of sea level rise on the shoreline was investigated since climate change is a rising concern. A conceptual model was set up consisting of a wave model in SWAN, which is a program for simulating nearshore waves. Then, calculations of the corresponding sediment transport rates along the shoreline were performed using the CERC formula. Through data analysis, the thesis showcases that the surrounding reef plays a key role in attenuating incoming wave energy since the wave height is drastically reduced once the waves pass over the reef. Moreover, the thesis highlights how a large extent, high density seagrass meadow will significantly reduce the incoming wave height, thus leading to lower sediment transport rates and coastal erosion on the shoreline. Finally, recommendations, ranging from stricter regulations to a transplantation program, are provided and discussed further in order to combat the rate of sediment transport and coastal erosion occurring in Le Morne.}},
author = {{Glatthaar, Julia and Espinosa, Paola Lucia}},
issn = {{1101-9824}},
language = {{eng}},
note = {{Student Paper}},
series = {{TVVR 5000}},
title = {{Study on the effect of seagrass meadows to mitigate coastal erosion: A case study of Le Morne, Mauritius}},
year = {{2025}},
}