Integrating mangrove growth and failure in coastal flood protection designs

Mangrove forests reduce wave attack along tropical and sub-tropical coastlines, decreasing the wave loads acting on coastal protection structures. Mangrove belts seaward of embankments can therefore lower their required height and decrease their slope protection thickness. Wave reduction by mangroves depends on tree frontal surface area and...

Optimising the wave attenuation of bamboo fences using the numerical wave model SWASH

The coastline of Demak, Indonesia, has been eroding during the<br/>last 15 years. Coastal retreat in Demak is caused by a combination<br/>of mangrove deforestation and local subsidence due to groundwater<br/>extraction in the nearby city of Semarang. To restore the lost mangrove<br/>forest, permeable dams, consisting of bamboo poles with a<br/...

Can cheniers protect mangroves along eroding coastlines? – The effect of contrasting foreshore types on mangrove stability

Mangrove forests are increasingly valued as wave-attenuating buffers in coastal flood defence strategies. However, as mangroves are vulnerable to wave-induced erosion, this raises the question, how can the stability of these protective mangrove forests be promoted? To address this question, we investigate how mangrove dynamics in a microtidal...

Restoring mangroves with structures: Improving the mangrove habitat using local materials

Mangrove forests effectively function as natural flood defences, and their deforestation has exposed millions of people worldwide to coastal erosion and flooding. Since mangroves require a stable sedimentary environment, stopping coastal erosion is a necessary step for their restoration. Bamboo structures have thus been built to induce accretion...

Predictive model of bulk drag coefficient for a nature-based structure exposed to currents

Mangrove vegetation provides natural protection against coastal hazards like flooding and erosion. In spite of their economic and societal value, mangrove forests have experienced a worldwide decline due to human activities. Bamboo structures, formed by poles driven into the soil, are being used to create a sheltered environment for mangrove...

Wave transmission and drag coefficients through dense cylinder arrays: Implications for designing structures for mangrove restoration

Mangrove vegetation constitutes a natural coastal defence against waves and erosion. Despite their protective role, mangrove ecosystems have experienced continuous degradation over the last decades due to human causes. At retreating mangrove coastlines, bamboo structures are built to create new habitat for mangrove colonization. Existing...

Mapping mangrove opportunities with open access data: A case study for Bangladesh

Mangroves protect coastal areas against hazards like storms or cyclones by attenuating waves and currents, and by trapping floating debris during extreme events. Bangladesh is a very vulnerable country to floods and cyclones, and part of its coastal system is thus being upgraded to a higher safety standard. These upgrades include embankment...

Managing erosion of mangrove-mud coasts with permeable dams – lessons learned

Mangrove-mud coasts across the world erode because of uninformed management, conversion of mangrove forests into aquaculture ponds, development of infrastructure and urbanization, and/or extraction of groundwater inducing land subsidence. The accompanied loss of ecosystem values, amongst which safety against flooding, has far reaching...

Wave transformation on the mangrove-mud coast of Demak, Indonesia

In this paper the typical hydrodynamics on mangrove-mud coasts are studied. Worldwide, these coasts experience serious erosion problems, and while the importance of mangrove ecosystems is becoming widely recognised, mangrove restoration projects frequently fail due to poor understanding of the system, especially the hydrodynamics. Therefore, a...

Wave attenuation by brushwood dams in a mud-mangrove coast

During recent decades, mangrove forests have experienced severe degradation due to unsustainable land use. Restoration of mangrove ecosystems requires the recovery of their habitat, considering ecology, hydrology, hydrodynamics, and sediment transport. In a first pilot in 2013, brushwood dams were built on the eroding coast of Demak, Indonesia,...