Publicação

Coastal sediments under the influence of multiple organic enrichment sources: an evaluation using carbon and nitrogen stable isotopes

Ver documento

Detalhes bibliográficos
Resumo:Sediment descriptors (grain size, total volatile solids, redox potential) and stable carbon and nitrogen isotopes were used to trace the origin of organic matter in a coastal area under multiple organic enrichment sources (urban outfall and a major estuary). The sediments fines content and total volatile solids were similar to outfall pre-operation period (1994), but the incorporation of terrestrial organic matter within the sediments located closer to the outfall was diagnosed by depleted (13)C values (-24.2+/-0.38 per thousand) and (15)N values (2.4+/-0.93 per thousand). Data also indicated depleted nitrogen signature at larger distances from the outfall than the carbon signature, due to confounding sediment grain size properties. Analysis in the bivalve Abra alba gave the same results for both isotopes and thus allowed a coherent interpretation of the spatial extent of the organic enrichment, highlighting the importance of bringing a biological element into the environmental assessment.
Autores principais:Sampaio, Leandro
Outros Autores:Freitas, Rosa; Máguas, Cristina; Rodrigues, Ana; Quintino, Victor
Assunto:Stable carbon and nitrogen isotopes Total volatile solids Redox potential Sediments grain size Organic enrichment Abra alba
Ano:2010
País:Portugal
Tipo de documento:artigo
Tipo de acesso:acesso restrito
Instituição associada:Universidade de Aveiro
Idioma:inglês
Origem:RIA - Repositório Institucional da Universidade de Aveiro
Descrição
Resumo:Sediment descriptors (grain size, total volatile solids, redox potential) and stable carbon and nitrogen isotopes were used to trace the origin of organic matter in a coastal area under multiple organic enrichment sources (urban outfall and a major estuary). The sediments fines content and total volatile solids were similar to outfall pre-operation period (1994), but the incorporation of terrestrial organic matter within the sediments located closer to the outfall was diagnosed by depleted (13)C values (-24.2+/-0.38 per thousand) and (15)N values (2.4+/-0.93 per thousand). Data also indicated depleted nitrogen signature at larger distances from the outfall than the carbon signature, due to confounding sediment grain size properties. Analysis in the bivalve Abra alba gave the same results for both isotopes and thus allowed a coherent interpretation of the spatial extent of the organic enrichment, highlighting the importance of bringing a biological element into the environmental assessment.