PARENT SESSION
Poster Session #13: Salt Marshes.
Monday, August 5. Presentation from 5:00 PM to 6:30 PM. Exhibit Hall B & C, TCC
127
Assessing habitat loss due to anthropogenic activity in the Mondego and Mira estuaries (Portugal).
Castro, Paula*,1, Freitas, Helena1, 1 Imar - Institute of Marine Research, Coimbra, Portugal
ABSTRACT- Destruction of habitat and nutrient enrichment, as a result of human impact, are growing problems in coastal wetlands. The findings that fringing salt marshes appear to intercept a substantial fraction of land-derived nitrogen loads and hence protect the quality of eelgrass habitats are certainly excellent reasons for the preservation of coastal salt marshes. This project was conducted in two Portuguese salt marshes: Mondego - central coast of Portugal and Mira - a narrow shallow tidal estuary located on the Southwest coast of Portugal. The main goals were to assess the changes in habitat area throughout the past century, as a result of human expansion in coastal areas; to assess the effect of eutrophication on species composition, biomass, and nitrogen content of salt marsh and seagrass meadows; and to use nitrogen isotope signatures to establish links between land-derived nitrogen and estuarine producers. Aerial photos and GIS analysis clearly indicated the degradation of Portuguese salt marshes and loss of about 90% seagrass habitats, during the last six decades in the Mondego estuary, as a consequence of several human activities developed in those areas. We believe that more information is needed to effectively manage coastal environment thus, the information collected in this work will be valuable to investigate whole-estuary human impact in coastal ecosystems and provide useful ecological information for managers, policy makers, and the stakeholders involved in estuary restoration.
KEY WORDS: Eutrophication, Salt marsh, Nitrogen, Seagrasses