Spatial and temporal variation of a nearshore benthic community in southern Brazil: Implications for the design of monitoring programs

Patterns of spatial variation in a soft bottom benthic assemblage were assessed throughout a year in a 10 m deep nearshore area of southern Brazil. At three different scales every 2 months, five replicate corer samples (0.008 m(2)) were taken at three random points (7 m(2)) within two sites (2000 m(2)). Spatial variation of the community was assessed by mixed ANOVA with two factors (Site and Time) crossed and one nested (Plot in Site). Variation presented a complex pattern indicating that even at such small scales, benthic community parameters (e.g. density, diversity, evenness) and dominant species differ in space and time. Results show the risk of pseudoreplication errors to which many monitoring programs and oceanographic surveys are subject whenever natural spatial variation of soft bottom benthic communities and vessel positioning precision are disregarded in designing a sampling program based on standard remote sampling methods. (C) 2001 Academic Press.