title: Radiotracer estimates of benthic activity effects on trace metal diffusion into mangrove sediments.
abstract: Potential influences of the whole benthic organisms' activity (i.e., coupled faunal and microbial effects) on (58)Co, (51)Cr and (65)Zn diffusion into surface mangrove sediment layers (0-6 cm depth) were evaluated in 36 h experiments. Benthic activity indices (BAI) were proposed, calculated as the relative percent difference between untreated sediments and formaldehyde-treated sediments data in relation to untreated sediments data. Benthic activity was estimated as responsible for 32%-44% of total inventories within sediments, being the chromate anion spiked the less affected radiotracer, while (65)Zn was the most sensitive. Benthic activity was quantitatively evidenced as a control on trace metal diffusion into the sediments, contributing to determine the sediment role as a metal sink. This influence can also affect metal potential bioavailability, considering that recently diffused metals can be more readily available to biological uptake.
authors.affiliation: Laboratório de Instrumentação Nuclear, COPPE, Universidade Federal do Rio de Janeiro, RJ, Brazil. norisuzuki6@yahoo.com.br
authors.forename: K N
authors.initials: KN
authors.lastname: Suzuki
authors.forename: E C
authors.initials: EC
authors.lastname: Machado
authors.forename: W
authors.initials: W
authors.lastname: Machado
authors.forename: L F
authors.initials: LF
authors.lastname: Bellido
authors.forename: A V B
authors.initials: AV
authors.lastname: Bellido
authors.forename: R T
authors.initials: RT
authors.lastname: Lopes
mesh_terms: D000818:Animals; D004058:Diffusion; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D008670:Metals / Q000032:analysis*; D011849:Radioactive Tracers; D014874:Water Pollutants, Chemical / Q000032:analysis*; D053833:Wetlands
chemical_list: D008670:Metals; D011849:Radioactive Tracers; D014874:Water Pollutants, Chemical