Wave attenuation potential, sediment properties and mangrove growth dynamics data over Guyana's intertidal mudflats: assessing the potential of mangrove restoration works

[摘要] Coastal mangroves, thriving at the interface between land and sea, providerobust flood risk reduction. Projected increases in the frequency andmagnitude of climate impact drivers such as sea level rise and wind and waveclimatology reinforce the need to optimize the design and functionality ofcoastal protection works to increase resilience. Doing so effectivelyrequires a sound understanding of the local coastal system. However, dataavailability particularly at muddy coasts remains a pronounced problem. Assuch, this paper captures a unique dataset for the Guyana coastline andfocuses on relations between vegetation (mangrove) density, wave attenuationrates and sediment characteristics. These processes were studied along across-shore transect with mangroves fringing the coastline of Guyana. Thedata are publicly available at the 4TU Centre forResearch Data (4TU.ResearchData) via https://doi.org/10.4121/c.5715269 (Best et al., 2022) where thecollection Advancing Resilience Measures for Vegetated Coastline (ARM4VEG), Guyana, comprises of six key datasets. Suspended sediment concentrations typically exceeded 1 g L −1 with a maximum of60 g L −1 , implying that we measured merely fluid-mud conditions across a 1 m depth. Time series of wind waves and fluid-mud density variations, recordedsimultaneously with tide elevation and suspended sediment data, indicatethat wave–fluid-mud interactions in the nearshore may be largely responsiblefor the accumulation of fine, muddy sediment along the coast. Sedimentproperties reveal a consolidated underlying bed layer. Vegetation coveragedensities in the Avicennia -dominated forest were determined across the vertical withmaximum values over the first 20 cm from the bed due to the roots andpneumatophores. Generalized total wave attenuation rates in the forest and along the mudflat were between 0.002–0.0032 m −1 and 0.0003–0.0004 m −1 respectively. Both the mangroves and the mudflats have a high wave-dampingcapacity. The wave attenuation in the mangroves is presumably dominated byenergy losses due to vegetation drag, since wave attenuation due to bottomfriction and viscous dissipation on the bare mudflats is significantly lowerthan wave dissipation inside the mangrove vegetation. Data collectedcorroborate the coastal defence function of mangroves by quantifying theircontribution to wave attenuation and sediment trapping. The explicit linkingof these properties to vegetation structure facilitates modelling studiesinvestigating the mechanisms determining the coastal defence capacities ofmangroves.

[学科分类] 眼科学