title: Spatial distribution of intertidal sandy beach polychaeta along an estuarine and morphodynamic gradient in an eutrophic tropical bay.
abstract: The spatial distribution of polychaeta along pollution gradients often reflects different degrees of disturbance. In order to evaluate polychaeta fauna of an organically polluted tropical bay, 20 sandy beaches distributed in five areas were sampled. The relationship between community structure, slope, beach index, exposure, sediment and water quality parameters were analysed. Multivariate analysis of variance (PERMANOVA) showed differences among areas and beaches. Scolelepis chilensis dominated at mouth of bay beaches whereas Streblospio gynobranchiata and Capitella capitata complex, at inner beaches. Highest polychaete density was recorded at areas 3 and 5 with the dominance of Saccocirrus sp. and the organic indicator species C. capitata complex and Polydora sp. The most important factors obtained from canonical analysis were sorting, slope, mud and organic matter percentage. Marine biotic index (AMBI) showed that areas 3 and 5 were highly affected by anthropogenic factors, given that a poor polychaeta fauna, dominated by opportunistic species, were found. Polychaete assemblages were affected by eutrophication along an estuarine gradient as well as by morphodynamic condition of the beaches.
authors: Departamento de Biologia Marinha, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Ilha do Fundão, 21941-913 Rio de Janeiro (RJ), Brazil. elianne.omena@yahoo.com.br
authors: E P
authors: EP
authors: Omena
authors: H P
authors: HP
authors: Lavrado
authors: R
authors: R
authors: Paranhos
authors: T A
authors: TA
authors: Silva
mesh_terms: D000818:Animals; D001493:Bathing Beaches; D061006:Bays / Q000737:chemistry; D044822:Biodiversity; D001938:Brazil; D004784:Environmental Monitoring; D063366:Estuaries; D005068:Eutrophication; D015999:Multivariate Analysis; D011077:Polychaeta / Q000145:classification / Q000254:growth & development*; D062206:Spatial Analysis; D014329:Tropical Climate; D014876:Water Pollution / Q000706:statistics & numerical data