El Niño Southern Oscillations and Pacific Decadal Oscillation as drivers of the decadal dynamics of benthic macrofauna in two subtropical estuaries (South Brazil)
MetadataShow full item record
The El Niño-Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) are large-scale climatic phenomena affecting atmospheric and oceanic teleconnections, and thus triggering weather events at different temporal and spatial scales, both in tropical and extratropical areas. During 11 years (2007 to 2017), the influence of ENSO events (El Niño, La Niña and Neutral), ENSO diversity (canonical and Modoki) and PDO (positive and negative phases) on meteorological conditions and macrobenthic invertebrates were analyzed in two distinct (tide-dominated and river-dominated) subtropical estuaries of southern Brazil. Despite their geographical proximity (only 85 km apart), and although both were affected by the PDO and ENSO, the estuaries exhibited clear meteorological differences determined by orographic processes. The benthic estuarine macrofauna was clearly distinct and with higher species richness in the tide-dominated estuary. The long-term variability of benthic macrofauna in both estuaries was strongly influenced by the PDO and ENSO events. However, the signs of PDO and ENSO effects differed between the studied estuaries. The tide-dominated estuary was primarily influenced by the PDO, and only secondarily by the ENSO. On the other hand, the river-dominated estuary showed an opposite behavior, with ENSO events as the main modulating force of decadal variability of macrobenthic invertebrate community. Our results also showed that PDO and ENSO events have combined effects on both estuaries, with higher macrofauna dissimilarities during constructive periods (PDO Positive/EL Niño vs. PDO Negative/La Niña).
The following license files are associated with this item:
- Click the Creative Commons icon for to know licensing terms