Juan Antonio Morales González

Distribución y ecologíade los foraminíferos y ostrácodos actuales del estuario mesomareal del río Guadiana (SO España)

In the Guadiana estuary, thirty-two recent samples were studied. The grain-size analysis differentiates between six distributions in the estuarine channel, four in the channel border and three in the salt marsh. The heavy metal concentration is low, with a maximum in the middle estuary, because of the floculation by water mixing. The three different estuarine zones (fluvial, middle and marine) have been distinguished by the tidal-fluvial interaction and the microfaune (ostracoda and foraminifera). The biometry study of any species delimited the post-mortem transport of these organisms, mainly during the tidal reflux.

The impact of man on the morphodynamics of the Huelva coast (SW Spain)

The Huelva coast is composed by large sandy beaches and spits, only interrupted by the presence of the estuarine mouths of the Guadiana, Piedras, Tinto-Odiel and Guadalquivir which are in an advanced state of sediment infilling. The morphology and processes of the Huelva coast are mainly linked to tidal regime, wave action, coastal-drift currents, fluvial dynamics, climatic change and anthropogenic activity. In the last five decades anthropogenic activity has modified the natural dynamics by the construction of jetties, docks, harbour and coastal developments. The main consequences have been the interruption of the sedimentary bypassing caused by an active west-to-east littoral drift, the modification of the tidal regime, the wave refraction-diffraction scheme and the intensification of the littoral erosive processes. All these effects will increase with the slow sea-level rise, close to 0.6 cm per year, which will induce a higher efficacy of the erosional events. A future retreat of about 10-15 m of the coastline is estimated.