Coastal wetlands are ecologically rich systems. They are getting more and more attention thanks to the ability to mitigate the effect of climate change by producing the buffer effect or mitigating extreme events due to weather perturbations. However, these systems have been subject to great anthropic pressure, a fact that has increased their degradation resulting in fragmented systems. A fragmented wetland presents disconnected areas, with gaps of vegetation, reducing the mitigation capacity against disturbances. The increase in the frequency and severity of extreme events is evident on a global scale. Added to these events, anthropic effects such as changes in the uses of river basins, and also in the management of coastal zones might be of special importance for wetlands.
Macrophytes capture the nutrients entering the wetland and prevent the eutrophication of the lagoons. However, a high level of fragmentation of the grassland vegetation of the wetland will allow the resuspension of the sediment and the contribution or subsequent increase of nutrients in the lagoons. The sediment in resuspension in a column of water reduces its quality, producing a negative feedback on macrophytes, endangering the resilience of the wetland.
The FragmentUm project will firstly determine the effect of extreme events on geomorphology and the role of aquatic vegetation in sediment stabilization. Second, the effect of the fragmentation of the meadow on the geomorphology against these extreme events will be studied. The three-dimensional structure of vegetation, as well as other parameters that characterize it (density, height, flexibility, type) are expected to be crucial to determine the functioning and persistence of coastal vegetation.