Premium
Morphological evolution of the Guadiana estuary and intertidal zone in response to projected sea‐level rise and sediment supply scenarios
Author(s) -
Sampath Dissanayake M.R.,
Boski Tomasz,
Silva Patricia L.,
Martins Flavio A.
Publication year - 2011
Publication title -
journal of quaternary science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.142
H-Index - 94
eISSN - 1099-1417
pISSN - 0267-8179
DOI - 10.1002/jqs.1434
Subject(s) - intertidal zone , estuary , salt marsh , sediment , holocene , geology , sedimentary budget , oceanography , beach morphodynamics , sedimentation , aggradation , sea level , fluvial , sediment transport , geomorphology , structural basin
Analysis of Holocene sediment accumulation in the Guadiana estuary (southern Portugal) during sea‐level rise since ca. 13 cal. ka BP was used to simulate the long‐term morphological evolution of the lower Guadiana estuary and the associated intertidal zone for 21st‐century predicted sea‐level rises. Three sea‐level rise scenarios given by the IPCC (2007) were used in the simulations of morphology using a large‐scale behaviour‐oriented modelling approach. Sedimentation rate scenarios were derived both from the Holocene evolution of the estuary and from a semi‐empirical estimation of present‐day sediment aggradation. Our results show that the net lateral expansion of the intertidal zone area would be about 3–5% of the present intertidal zone area for each 10 cm rise in sea level. Under constraints imposed by the lack of fluvial sediment supply, the lateral expansion of the landward boundary of the intertidal zone will occur mainly in the Portuguese margin of the Guadiana estuary, while submergence of the salt marshes will occur in the Spanish margin. Therefore the Spanish margin is highly vulnerable to both sea‐level rise and lack of sediment supply. Copyright © 2011 John Wiley & Sons, Ltd.