Made available in DSpace on 2014-12-17T14:01:58Z (GMT). No. of bitstreams: 1 AlineSM.pdf: 1989491 bytes, checksum: 8a1f759349023fd90f5d13c4289e236d (MD5) Previous issue date: 2008-03-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The mollusks present a great taxon variety and life habits in coral reefs being good environmental indicators. It is important to know the distribution pattern of the mollusks and the processes that influence it, so that disturbances in sea ecosystems could be monitored. The present study aims to accomplish the inventory and distribution of epibenthic mollusks in the Parracho of Maracaja?. 23 sites in different habitats of the Parracho were settled: 11 in the reef habitat, 3 in the sandy bottom and 9 in the seagrass bed. Qualitative and quantitative samplings have been done through snorkeling and scuba diving. Three band transects (10m?) were sampled in each site and the data were obtained to each m? of the transect, where the species were counted and the environmental variables (rugosity and recovery of the substratum) were valued. The data were submitted to multivariate analyses in order to find possible distribution patterns that could be associated to the substratum variables. The diversity indexes were calculated for each reef sites and compared with each other. A number of 46 species were registered. The reef habit at should to be the richnest area while the sandy bottom was poorest one. In the reef habitat, the mollusks were associated to rugosity and recovering of frondose algae and zoanthids, while for the seagrass bed, the animals exhibited a richness variation associated to the muddy and sandy sediment. There were found 3 species economically explored, what requires an appropriate management for the maintenance and conservation of the area resources in a sustainable way / Os moluscos apresentam uma grande variedade de t?xons e h?bitos de vida nos recifes de coral mostrando-se bons indicadores ambientais. ? importante conhecer sua istribui??o e os fatores de influ?ncia a fim de auxiliar no monitoramento de poss?veis dist?rbios no ambiente marinho. O presente estudo teve por objetivo realizar o levantamento e distribui??o dos moluscos epibent?nicos no Parracho de Maracaja?. Foram definidos 23 s?tios de amostragem nos diferentes habitats do Parracho sendo 11 no habitat recifal, 3 no fundo arenoso e 9 nas faner?gamas marinhas. Foram realizadas amostragens qualitativas e quantitativas atrav?s de mergulhos livres e aut?nomos para obten??o dos dados de moluscos e caracter?sticas do substrato. Em cada s?tio foram amostrados 3 transec??es em faixa de 10 m?, onde os dados foram registrados a cada m? da transec??o, sendo ent?o contadas as esp?cies e valoradas as vari?veis ambientais (rugosidade e cobertura do substrato). Os dados foram submetidos a an?lises multivariadas para encontrar poss?veis padr?es de distribui??o, associadas ?s vari?veis de substrato mensuradas. Tamb?m foram calculados os ?ndices de diversidade para os s?tios recifais e comparados entre si. Registraram-se 46 esp?cies, com maior riqueza no habitat recifal, seguida nas faner?gamas marinhas e com menor valor, no fundo arenoso. No habitat recifal, os moluscos apresentaram-se associados ? rugosidade e cobertura de algas frondosas e zoant?deos, enquanto nas faner?gamas, os animais exibiram uma varia??o de riqueza associada ao sedimento lamoso e arenoso. Foram encontradas 3 esp?cies exploradas comercialmente, sendo necess?rio o manejo adequado visando a manuten??o e conserva??o dos recursos para a regi?o