The current status of mangrove forests in Spanish Lagoon (Aruba) evaluated from a hydrological point of view. Assessing the water balance and modelling tree growth rates.

The importance of mangroves is widely recognized because of the number of services they provide (e.g. habitat function and coastal protection). In this study the current status of the mangrove forest in Spanish Lagoon (Aruba) is evaluated from a hydrological point of view, in order to determine whether these services are threatened. During a three month period of fieldwork both the salt and freshwater supply was quantified. In addition, the biomass of the forest was estimated. The average biomass found in this study compares reasonably well to those found in Puerto Rico and Sri Lanka. 

Moreover, a model was developed to simulate tree growth under the current hydrological regime. Mangrove growth in the canal, which is in open connection with the sea, was compared to growth in the hinterland of Spanish Lagoon. The model results indicate that growth is not limited in the current hydrological conditions, neither for the mangroves along the canal nor for the mangroves in hinterland. However, a sensitivity analysis shows that the hinterland is sensitive to increased salt concentrations. Blocking of seawater inflow by mangroves is the biggest threat for tree growth in the hinterland, since it can lead to increased salt concentrations; potentially causing a reduced tree growth.