title: Comparison of rates of flagellate bacterivory and bacterial production in a marine coastal system.
abstract: Protozoan predation on bacteria and bacterioplankton secondary production were simultaneously determined in La Salvaje Beach water during 1990. Protozoan grazing on bacterioplankton was measured from fluorescently labeled bacterium uptake rates; estimates of bacterial secondary production were obtained from [H]thymidine incorporation rates. Two different conversion factors were used to transform thymidine incorporation rates into bacterial production rates; both of them were specific for La Salvaje Beach and were calculated by using empirical and semitheoretical approaches. The average flagellate predation rate was 14.0 bacteria flagellate h; the average population predation rate was 7.35 x 10 bacteria liter h. The estimates of bacterial production differed greatly depending on the conversion factor used, and so did the percentages of bacterial production consumed by flagellated protozoa (4.6% when the empirical conversion factor for La Salvaje Beach was used and 113% when the semitheoretical conversion factor specific for this system was used). The ecological implications of each of these values are discussed.
authors.affiliation: Departamento de Microbiología e Inmunología, Facultad de Ciencias, Universidad del País Vasco, Apartado 644, E-48080, Bilbao, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Barcina
authors.forename: B
authors.initials: B
authors.lastname: Ayo
authors.forename: M
authors.initials: M
authors.lastname: Unanue
authors.forename: L
authors.initials: L
authors.lastname: Egea
authors.forename: J
authors.initials: J
authors.lastname: Iriberri