Abstract Submittal Deadline
21 January 2011

Late Registration
Fees Imposed

Beginning 1 April 2011

Program and Schedules Available
Late March 2011

Meeting
22-26 May 2011

Rios-Touma, B., Laboratorio de Ecología Acuática-USFQ / Freshwater Ecology and Management Group UB, Quito, Ecuador, brios@ub.edu
Encalada, A. C., Laboratorio de Ecología Acuática Universidad San Francisco de Quito, Quito, Ecuador, aencalada@usfq.edu.ec
Gonzalez, F., Laboratorio de Ecología Acuática Universidad San Francisco de Quito, Quito, Ecuador, fernany83@hotmail.com
Rieradevall, M., Freshwater Ecology and Management Group / Universitat de Barcelona, Barcelona, Spain, mrieradevall@ub.edu
Prat, N., Freshwater Ecology and Management Group / Universitat de Barcelona, Barcelona, Spain, nprat@ub.edu

IS FLOW SHAPING THE STRUCTURE AND FUNCTION OF MACROINVERTEBRATE COMMUNITIES AT AN ANDEAN STREAM?

Between 2009 and 2010 we followed flow changes and macroinvertebrate communities of Saltana creek, located at the Eastern Andean Range (3800 m asl) in Ecuador. Our aim was to characterize the hydrology and to test whether seasonal differences in flow during a year were associated to changes in abundance and composition (taxonomical and functional) of macroinvertebrate communities. Stream flow was followed using a depth logger at a fixed flow transect, while twelve small Hess samples (0.02 m2) were taken every month to assess macroinvertebrate communities. Stream flow fluctuated between 33.1 and 469.54 l/s with an annual mean of 130 l/s. Taxonomical and functional composition was similar in months were flow was below the mean. Density and biomass of most abundant taxa changed according to different flow situations (e.g. Andesiops density and biomass decreased as flow decreased). Also several traits were related to flow changes (e.g. proportion of tarsal hooks increased as flow increased). Our study suggests that flow changes have strong influence on the response of some benthic macroinvertebrates of high-altitude Andean streams that are related to specific biological traits.

Session #:T06A
Date: 5/25/2011
Time: 08:30