Chenier Dynamics

Over the last decades, mangrove forests have suffered immense and rapid losses worldwide. In recognition of their important socio-economic and environmental functions, many attempts have been made to both protect the remaining mangrove coastlines and restore eroding sites. Unfortunately, many rehabilitation attempts have failed, lacking a...

Chenier Formation Through Wave Winnowing and Tides

Cheniers are ridges consisting of coarse-grained sediments, resting on top of the fine sediment that forms the otherwise muddy coast. In this paper, we use Delft3D to explore how cheniers are formed through wave winnowing. We identify three phases of chenier development: (a) a winnowing phase, during which mud is washed out of the seabed...

Drivers of cross-shore chenier dynamics off a drowning coastal plain

A chenier is a beach ridge, consisting of sand and/or shells, overlying a muddy substrate. In this paper, we explore the cross-shore dynamics of cheniers in their ‘active’ phase, i.e. the phase between their formation and their landing on the shore and can no longer be reached by daily wave and tidal influences. While cheniers described in...

Observations of cross-shore chenier dynamics in Demak, Indonesia

Cheniers are important for stabilising mud-dominated coastlines. A chenier is a body of wave-reworked, coarse-grained sediment consisting of sand and shells overlying a muddy substrate. In this paper we present and analyse a week of field observations of the dynamics of a single chenier along the coast of Demak, Indonesia. Despite relatively...

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,...

Regions of fresh water influence: The influence of depth on a ROFI

The topic of this paper is the study of the tidal velocity profiles within a region of fresh water influence (referred to as ROFI in this paper). These regions of fresh water influence occur where rivers discharge fresh water into salty seas. The main research question is how depth influences the behaviour of the tidal velocity profile in a...