Flow regulation by dams affects ecosystem metabolism in Mediterranean rivers
Article first published online: 7 MAY 2014
© 2014 John Wiley & Sons Ltd
Volume 59, Issue 9, pages 1816–1829, September 2014
How to Cite
Aristi, I., Arroita, M., Larrañaga, A., Ponsatí, L., Sabater, S., von Schiller, D., Elosegi, A. and Acuña, V. (2014), Flow regulation by dams affects ecosystem metabolism in Mediterranean rivers. Freshwater Biology, 59: 1816–1829. doi: 10.1111/fwb.12385
- Issue published online: 9 JUL 2014
- Article first published online: 7 MAY 2014
- Manuscript Accepted: 4 APR 2014
- Spanish Ministry of Economy and Competitiveness through the project SCARCE Consolider-Ingenio CSD2009-00065
- University of the Basque Country
- Basque Government (Consolidated Research Group: Stream Ecology 7-CA-18/10)
- Juan de la Cierva. Grant Numbers: jci-2009-05604, jci-2010-06397
- Marie Curie European Reintegration Grant. Grant Number: PERG07-GA-2010-259219
- Generalitat de Catalunya (Consolidated Research Group 2009 SGR-00759
- ecosystem metabolism;
- flow regulation;
- Mediterranean rivers;
- organic carbon dynamics
- Large dams regulate river hydrology and influence water chemistry, sediment dynamics, channel form and biotic communities. These effects may translate into important changes in river ecosystem processes, especially in rivers naturally subject to strong seasonality, such as those under Mediterranean climate.
- The effects of flow regulation on ecosystem metabolism [i.e. gross primary production (GPP) and ecosystem respiration (ER)] were analysed by means of open-stream measurements. Organic matter accrual and metabolism were measured in reaches upstream and downstream from large reservoirs in three tributaries of the Ebro River (NE Iberian Peninsula) during three sampling campaigns.
- Dams reduced downstream hydrological variability, dampened floods and increased the duration of interflood periods. Benthic organic matter increased twofold and chlorophyll-a eightfold. GPP increased by 59% on average, whereas ER increased by 75%.
- In general, flow regulation intensified the capacity of downstream river reaches to store and process materials and energy, therefore increasing the amount of organic carbon processed and altering the whole flux of materials and energy along the river continuum.