Environmental forcing and larval fish assemblage dynamics in the Lima River estuary (northwest Portugal)

• Type: Article in International Scientific Journal
• Date: 2006

Authors

Ramos, S (Author) Other; Cowen, RK (Author) Other; Paris, C (Author) Other; Re, P (Author) Other; Adriano Bordalo (Author) ICBAS

Journal

Title: Journal of Plankton Research

Vol. 28

Pages: 275-286

ISSN: 0142-7873

Publisher: Oxford University Press

Indexing

ISI Web of Knowledge - 19 Citations

Scopus - 16 Citations

Other information

Authenticus ID: P-004-N1Z

DOI: 10.1093/plankt/fbi104

Abstract (EN): This study investigated the potential control of selected abiotic parameters on an estuarine larval fish assemblage from the Lima River. Surveys were done fortnightly during spring tides, from April 2002 until April 2004, at 11 stations distributed along the estuary from the mouth to 7 km upstream. The surveys consisted of subsurface plankton tows of 5-min duration using a 1-m diameter, 500-mu m mesh net and coupled with vertical profile measurements of temperature, salinity, dissolved oxygen, pH and turbidity. The Lima River estuary exhibited seasonal vertical stratification of salinity during the winter period, when salinity sharply increased with depth and a layer of fresh water was sometimes present at the surface. Temperature was always vertically stratified. Cooler water was typically found near the bottom of the water column, except during winter, when a thermal inversion occurred. A seasonal decrease in abundance and diversity of the larval assemblage was observed during winter, when fish larvae were almost absent from the plankton collections. Canonical correspondence analysis (CCA) results showed that the first axis represented a temporal gradient and the second axis represented a spatial gradient. Seasonal variations on temperature and precipitation were responsible for the temporal differences on the fish larval assemblages. This study reinforced the concept that interannual climate and hydrodynamic variations have a strong influence on estuarine ichthyoplankton and, consequently, on the recruitment of marine coastal fish populations.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12