A 10-year survey of trace metals in sediments using self-organizing maps

Self-organizing maps (SOMs) (in particular, Matrix reOrganization Layout to Map Analytical Patterns (MOLMAP)) were used to unravel the main patterns in a three-way dataset after a preliminary unfolding of the cube. Eleven sites of the ría of Vigo (NW of Spain) were monitored during the last decade (...

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Detalles Bibliográficos
Autores: Besada, Victoria, Quelle, Cristina, Andrade, José Manuel, Gutiérrez, Noemí, Gómez-Carracedo, María Paz, Schultze, Fernando
Tipo de recurso: artículo
Fecha de publicación:2014
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/321655
Acceso en línea:http://hdl.handle.net/10261/321655
Access Level:acceso abierto
Palabra clave:Medio Marino
Self-organizing maps
Centro Oceanográfico de Vigo
Three-way unfolding
Three-way unsupervised pattern recognition
Trace metals
Sediments
Descripción
Sumario:Self-organizing maps (SOMs) (in particular, Matrix reOrganization Layout to Map Analytical Patterns (MOLMAP)) were used to unravel the main patterns in a three-way dataset after a preliminary unfolding of the cube. Eleven sites of the ría of Vigo (NW of Spain) were monitored during the last decade (from 2000 to 2010) to assess pollution trends in this area. Twelve trace metals (Hg, Pb, Cd, Cu, Zn, Cr, As, Li, Fe, Al, Ni and Mn), the total organic carbon and the percentage of fine particles were measured. Results from MOLMAP, the SOM-based approach, were compared to those of three established alternatives: parallel factor analysis, matrix-augmented principal component analysis and generalized Procrustes rotation, the latter two employing unfolding as well. MOLMAP showed the best capabilities to differentiate groups of samples. The spatial and temporal trends, as well as the analytical variables causing them, were almost the same for all methods, which confirms MOLMAP as a simple and reliable methodology to treat three-way environmental datasets