Inter-annual changes in fish communities of a tropical bay in southeastern Brazil: What can be inferred from anthropogenic activities?
We assessed inter-annual changes in fish assemblages of a tropical bay which experienced a heavily industrialized process in the last decades. A highly significant difference in community structure among the bay zones, and a decrease in fish richness and abundance over time were found. Changes in fish richness and abundance between the two first (1987-1988 and 1993-1995) and the two latter time periods (1998-2001 and 2012-2013) were sharpest in the inner bay zone, the most impacted bay area, and in the middle zone, whereas the outer zone remained comparatively stable over time. These changes coincided with increased metal pollution (mainly, Zn and Cd) in the bay and with the enlargement of the Sepetiba Port. Spatial changes in the fish community structure among the bay zones were related to differences in salinity, transparency and depth with this latter variable acting as a buffer stabilizing temporal community changes.
Laboratorio de Ecologia de Peixes, Universidade Federal Rural do Rio de Janeiro, BR 465, Km 7, 23.890-000 Seropédica, Rio de Janeiro, Brazil. Electronic address: gerson@ufrrj.br.
Francisco Gerson
FG
Araújo
Laboratorio de Ecologia de Peixes, Universidade Federal Rural do Rio de Janeiro, BR 465, Km 7, 23.890-000 Seropédica, Rio de Janeiro, Brazil.
Samara Macedo
SM
Pinto
Laboratorio de Ecologia de Peixes, Universidade Federal Rural do Rio de Janeiro, BR 465, Km 7, 23.890-000 Seropédica, Rio de Janeiro, Brazil.
Leonardo Mitrano
LM
Neves
Laboratorio de Ecologia de Peixes, Universidade Federal Rural do Rio de Janeiro, BR 465, Km 7, 23.890-000 Seropédica, Rio de Janeiro, Brazil.
Márcia Cristina Costa
MCC
de Azevedo
D000818:Animals; D061006:Bays / Q000737:chemistry; D044822:Biodiversity; D001938:Brazil; D004784:Environmental Monitoring / Q000379:methods*; D005399:Fishes / Q000145:classification* / Q000254:growth & development; D008670:Metals
D008670:Metals
Brazil; Depth gradient; Environmental factors; Estuarine fish; Temporal changes; Tropical systems